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Review

The Physiological and Pathological Role of Acyl-CoA Oxidation

1
Department of Biochemistry, Faculty of Medicine, Medical University of Gdansk, 80-211 Gdansk, Poland
2
Department of Pharmaceutical Biochemistry, Faculty of Pharmacy, Medical University of Gdansk, 80-211 Gdansk, Poland
3
Institue of Nursing and Medical Rescue, State University of Applied Sciences in Koszalin, 75-582 Koszalin, Poland
*
Authors to whom correspondence should be addressed.
These authors contributed equally to this work.
Int. J. Mol. Sci. 2023, 24(19), 14857; https://doi.org/10.3390/ijms241914857
Submission received: 25 August 2023 / Revised: 27 September 2023 / Accepted: 30 September 2023 / Published: 3 October 2023
(This article belongs to the Special Issue CoA in Health and Disease 2.0)

Abstract

:
Fatty acid metabolism, including β-oxidation (βOX), plays an important role in human physiology and pathology. βOX is an essential process in the energy metabolism of most human cells. Moreover, βOX is also the source of acetyl-CoA, the substrate for (a) ketone bodies synthesis, (b) cholesterol synthesis, (c) phase II detoxication, (d) protein acetylation, and (d) the synthesis of many other compounds, including N-acetylglutamate—an important regulator of urea synthesis. This review describes the current knowledge on the importance of the mitochondrial and peroxisomal βOX in various organs, including the liver, heart, kidney, lung, gastrointestinal tract, peripheral white blood cells, and other cells. In addition, the diseases associated with a disturbance of fatty acid oxidation (FAO) in the liver, heart, kidney, lung, alimentary tract, and other organs or cells are presented. Special attention was paid to abnormalities of FAO in cancer cells and the diseases caused by mutations in gene-encoding enzymes involved in FAO. Finally, issues related to α- and ω- fatty acid oxidation are discussed.

1. Introduction

Fatty acids (FAs) are critical compounds for the health control and development of the human body due to their participation in cellular metabolism, especially energy production (ATP synthesis), metabolism regulation, and cell proliferation. They are (a) building blocks for complex lipids in cellular membranes, (b) precursors for signaling molecules, such as eicosanoids, (c) allosteric regulators of metabolic pathways, (d) substrates for protein acylation, and (e) ligands for transcription factors. FAs are also responsible for lipotoxicity and contribute to the release of proinflammatory molecules, which play an important role in many diseases. Moreover, an increase in citrate, isocitrate, and malate production associated with free fatty acid (FFA) β-oxidation (βOX) leads to increased NADPH levels in some cells. Cytosolic isocitrate dehydrogenase (which catalyzes the conversion of isocitrate in the presence of NADP to α-ketoglutarate and NADPH) and a cytosolic malic enzyme (ME) (which catalyzes the conversion of malate in the presence of NADP to pyruvate and NADPH) play an important role in NADPH homeostasis.
The most important sources of FAs found in humans include dietary supply, mainly triacylglycerols, and de novo synthesis, mainly from glucose [1].
As already mentioned, FAs serve a predominant role as substrates for ATP production in many human and animal organs, including the heart, skeletal muscle, kidney, and liver. Over 20 proteins are involved in the uptake, activation, transport into the organelles (mainly mitochondria and peroxisomes), and finally, fatty acid oxidation (FAO). The most important process of FAO-βOX occurs primarily in the mitochondria of many organs and, to a lesser extent, in peroxisomes, mainly in the liver and kidney. In peroxisomes, not only βOX but also α-oxidation takes place. Alfa oxidation produces a fatty acyl CoA, one carbon shorter [2]. From a practical point of view, this process plays an important role in the oxidation of phytanic acid (a compound present in the human diet, originating mainly from ruminant animals and fish) [3]. ω-oxidation undergoes in microsomes (smooth endoplasmic reticulum) [4]. In this process, FAs are degraded starting from the end methyl group (so-called ω-carbon) of FAs, and the CYP (cytochrome P-450) family is involved. ω-oxidation is considered a rescue process for some genetic diseases in humans, in which mitochondrial and peroxisomal FA oxidation is impaired. Interestingly, phytanic acid also undergoes ω-oxidation [2].
The energy production from FAs is strictly associated with the mitochondrial βOX. The intensity of βOX is controlled by a plethora of regulatory factors, including the supply of nutrients and the action of several hormones, including insulin, glucagon, catecholamines, triiodothyronine, and cortisol. The crucial regulator of FAO is peroxisome proliferator-activated receptor α (PPARα) [5]. PPARα is a transcription factor that functions as a heterodimer in complex with the retinoid X receptor α (RXRα) and binds via the PPARα DNA-binding domain (DBD) to the PPRE (peroxisome proliferator response element) sequence in the promoter region of target genes involved mainly in hepatic and cardiac muscle FA and FAO [6]. The initiation of transcription by PPARα (similar to other PPARs) requires its activation. Briefly, in its inactive form, the PPARα-RXRα complex is associated with corepressors [7]. The complex activation occurs following ligand binding [8]. A wide range of lipophilic molecules can activate PPARα. These include natural saturated, unsaturated, and polyunsaturated fatty acids (PUFAs) and synthetic ligands, collectively called PPARα activators [7,9]. The natural ligands show different binding affinities and strengths of PPARα activation. The potent PPARα ligands are unsaturated fatty acids, including omega-3 eicosapentaenoic acid (20:5, ω3), docosahexaenoic acid (22:6, ω3), and phytanic acid [10,11]. The natural and synthetic ligands (pharmacological ligands, for instance, fibrates) directly bind to PPARα via the ligand-binding domain (LBD). The ligand binding to a nuclear receptor causes the release of corepressors and begins the recruitment of coactivator complexes to the PPARα-RXRα, which enables the activation of the expression of genes involved in FAO [7]. PPARα is expressed at the highest level in hepatocytes, cardiomyocytes, enterocytes, and kidney proximal tubule cells, which are involved in the increased FAO [12], as we describe in this review. Other members of the PPARs family—PPARβ/δ and PPARγ—are involved in the regulation of different processes generally associated with lipid metabolism. PPARβ/δ participates in the activation of FAO [13]. It has been observed that expression of the PPARβ/δ genes increases in skeletal muscles after fasting and endurance exercises, which promotes the transition from glucose, as the primary source of energy substrate, to lipids [14,15,16,17]. In comparison, PPARγ plays an important role in adipogenesis, lipid uptake, triacylglycerols (TAG) storage, and lipid droplet formation [18].
In this review, we first described a general aspect of the FAs transport (into the cells and then mitochondria) and activation. Then, we concentrated on FAO under physiological and pathological conditions in the liver, heart, skeletal muscle, kidney, and other organs. Special attention has been paid to FAO abnormalities in cancer cells and the diseases caused by mutations in genes encoding enzymes involved in FAO.

1.1. Uptake and Activation of Fatty Acids

In blood, FAs are present as components of lipids in (a) cell membranes (mainly in erythrocytes and white blood cells), (b) lipoproteins (mainly in chylomicrons, VLDL, LDL, and HDL), and (c) FFAs mostly bound to albumin. The major FAs in the whole lipids in the blood are palmitic acid (C16:0), stearic acid (C18:0), oleic acid (C18:1), linoleic acid (C18:2), and arachidonic acid (C20:4) [19,20]. The concentration of FFAs in the serum increases during exercise or fasting, and they are mainly used as FAO substrates in skeletal muscles, the heart, liver, and kidney [21]. The physiological FFA concentration in blood is around 0.2–0.5 mmol/L [22]. Due to their low solubility in H2O (1–10 nmol/L, depending on FA chain length), FFAs (mainly long-chain—LCFAs and medium-chain—MCFAs) are attached to the albumin [23]. Binding the FFAs to the albumin (a) enables transport in the blood and (b) protects human organs against some pathologies, including insulin resistance, non-alcoholic fatty liver disease, atherosclerosis, and heart dysfunction [24,25]. FFAs are translocated from the albumin FFA complex into the target cell (cells where FFAs are metabolized) cytosol across the endothelial layer of the blood vessels [26]. In the liver, the sinusoidal endothelial cells are fenestrated and do not have a basement membrane, so the absorption of FFAs is much easier than in other organs [27]. The transfer of FFAs from the blood to other cells, for instance, cardiomyocytes, seems to be more complicated since the endothelial wall in the heart capillaries is not-fenestrated and the FFAs are transferred through three lipid membranes: two endothelial (in and out of the endothelial cells) and one myocyte membrane (transported into the cell). Arts et al. proposed a model of FFA translocation across heart capillaries into cardiomyocytes, where FFAs bind to compartment-specific carrier proteins [28]. According to this model, the crossing of the plasma membrane remains under the control of several proteins, including (a) cluster of differentiation-36 (also known as FA translocase—CD36), (b) FA-binding protein—FABPm, and (c) FA-transporting protein—FATP (Figure 1). These proteins enable the cell to control the inflow of FFAs precisely. They increase the uptake of FFAs at the beginning of muscle contraction, even if the concentration of FFAs in the blood is low. Moreover, they also prevent the entrance of excess FFAs into the cell and help to select FFAs according to the cell’s demand. It should be noted that FFAs may also translocate into the target cell by a flip-flop system driven by the FFA concentration gradient [28].
The delivery of FFAs to the cells and their activation before usage in several cellular processes involves many proteins, including enzymes (Figure 1). Among these proteins are FATPs, which exhibit acyl-CoA synthetase activity. These two functions of FATPs (transport and activation) enable the immediate utilization of FFAs in the cell. Other proteins, like FABPm, CD36, and a family of acyl-CoA synthetases (ACSs), form an integrated system of the transport and activation of LCFAs, MCFAs, and short-chain FAs (SCFAs). FABPc proteins are also involved in binding FFAs in the cytosol (Figure 1).
FFAs are activated by specific ACSs. After activation, some FFAs become bound by the acyl-CoA-binding proteins (ACBPs). The binding of FFAs is responsible for channeling acyl-CoA to particular cellular compartments and processes. Acyl-CoA’s minor pool is deacylated by acyl-CoA diesterases (ACOTs) [29,30]. However, the physiological significance of deacylation is unknown. Very recently, it has been reported that ACOT1 knock-out partially protects mice from high-fat diet-induced weight gain by increasing energy expenditure [31]. Thus, these results suggest that inhibition of ACOT1 could prevent obesity during caloric excess.
Figure 1. Fatty acid transport and metabolism in the cell. CAC—acylcarnitine translocase, CP—carnitine palmitoyltransferase, FABP—fatty acid-binding protein, LCEH—long-chain enoyl-CoA hydratase, LCHAD—long-chain fatty acid hydroxy acyl-CoA dehydrogenase, LCKAT—long-chain fatty acid β-ketothiolase, MCAD—medium-chain acyl-CoA dehydrogenase, MCKAT—medium-chain ketoacyl-CoA thiolase, OXPHOS—oxidative phosphorylation, SCAD—short-chain acyl-CoA dehydrogenase, SCHAD—short-chain hydroxy acyl-CoA dehydrogenase, TCA—Krebs cycle, VLCAD—very-long-chain acyl-CoA dehydrogenase, OCTN2—carnitine transporter, present in the heart, skeletal muscle, and kidney (hepatocytes have a different translocator with low affinity and high capacity), FABPm—membrane fatty acid-binding protein, FABPc—cytosolic fatty acid-binding protein, MTP—mitochondrial trifunctional protein, MTP ? – possible involvement of MTP protein, CD-36—fatty acid translocase, FATP—fatty acid transporting protein (the acyl-carnitines are transported across the outer mitochondrial membrane via a voltage-dependent anion channel (VDAC) [32]).
Figure 1. Fatty acid transport and metabolism in the cell. CAC—acylcarnitine translocase, CP—carnitine palmitoyltransferase, FABP—fatty acid-binding protein, LCEH—long-chain enoyl-CoA hydratase, LCHAD—long-chain fatty acid hydroxy acyl-CoA dehydrogenase, LCKAT—long-chain fatty acid β-ketothiolase, MCAD—medium-chain acyl-CoA dehydrogenase, MCKAT—medium-chain ketoacyl-CoA thiolase, OXPHOS—oxidative phosphorylation, SCAD—short-chain acyl-CoA dehydrogenase, SCHAD—short-chain hydroxy acyl-CoA dehydrogenase, TCA—Krebs cycle, VLCAD—very-long-chain acyl-CoA dehydrogenase, OCTN2—carnitine transporter, present in the heart, skeletal muscle, and kidney (hepatocytes have a different translocator with low affinity and high capacity), FABPm—membrane fatty acid-binding protein, FABPc—cytosolic fatty acid-binding protein, MTP—mitochondrial trifunctional protein, MTP ? – possible involvement of MTP protein, CD-36—fatty acid translocase, FATP—fatty acid transporting protein (the acyl-carnitines are transported across the outer mitochondrial membrane via a voltage-dependent anion channel (VDAC) [32]).
Ijms 24 14857 g001
According to the chain length, influencing the hydrophobicity and water solubility of FFAs, four ACS families have been established: (a) short-chain acyl-CoA synthetases (ACSSs), (b) medium-chain acyl-CoA synthetases (ACSM), (c) long-chain acyl-CoA synthetases (ACSLs), and (d) very-long-chain acyl-CoA synthetases (ACSVLs) [33]. An overview of the characteristics of ACS isoforms is presented in Table 1.
Except for lauric acid, MCFAs are activated and oxidized in mitochondria [45,48].

1.2. Carnitine Shuttle

1.2.1. Carnitine Palmitoyltransferase 1 (CPT1)

The inner mitochondrial membrane is impermeable to the long-chain acyl-CoAs. Thus, the acyl-CoAs are converted to acylcarnitine in the reaction catalyzed by carnitine palmitoyltransferase 1 (CPT1):
acyl-CoA + carnitine → acylcarnitine + CoASH
CPT1 is a hexamer, a part of a protein complex formed and attached to the outer mitochondrial membrane. Other elements of that complex are ACSL and VDAC (voltage-dependent anion channel) [49,50]. Three isoforms of CPT1 are known: CPT1A, CPT1B, and CPT1C. CPT1A is the main CPT1 in the liver, but it is also present in minor amounts in the heart, skeletal muscles, brain, kidneys, lungs, spleen, intestine, pancreas, ovaries, and fibroblasts. It is involved in transporting LCFAs and medium-chain lauric acid (C:12) into mitochondria, though its highest activity is in lauric acid. CPT1B is the dominating form in the skeletal muscles, heart, and testes, and like CPT1A, it is an enzyme transporting LCFAs to mitochondria, with the highest activity in C12-C16 FFAs. CPT1C is a neural form attached to endoplasmic reticulum (ER) membranes. Potentially, it is involved in the neuronal control of thermogenesis in brown adipose tissue (BAT) [51,52]. CPT1C activity is significantly (20–300 times) lower than CPT1A [53,54,55]. CPT1A and B share 62% similarity in the amino acid sequence. Both isoforms differ significantly in activity and regulation [56].
A high-fat diet induces the expression of the CPT1 gene by the PPARα transcription factors in the liver and muscles [5,57,58]. Insulin, glucagon, and triiodothyronine regulate CPT1 activity in the liver, and the physiological status significantly influences that regulation [57,59,60,61]. The major regulator of CPT1 is malonyl-CoA, a negative allosteric effector of this enzyme. The intracellular level of malonyl-CoA depends on acetyl-CoA carboxylase (ACC—enzyme-synthesizing malonyl-CoA) activity and malonyl-CoA decarboxylase (MCD—enzyme-degrading malonyl-CoA) activity [62,63,64,65]. Malonyl-CoA, an intermediate in palmitate synthesis, inhibits FAO during intensive FFA synthesis. It protects the cell from the immediate oxidation of the newly synthesized FFAs [52]. At a negative energy balance, when the activity of MCD is elevated, CPT1 restores its activity, leading to efficient acylcarnitine synthesis. It should be noted that CPT1B is activated mainly by exercise and is more sensitive to changes in the malonyl-CoA level.
Both LCFAs and MCFAs stimulate CPT1 activity during the exercises [66]. A high-fat diet or fasting induces the expression of the CPT1 gene by the two independent systems involving PPARα transcription factors or the PGC1α/PPARγ complex in the liver and muscles. The binding site in the Cpt1 gene for PPARα in the rat liver is located in the second intron and PGC1α/PPARγ in the first intron [5,57,66]. Mutations in PPRE totally eliminate the induction of Cpt1 gene expression by both regulatory systems [5].
Carnitine is transported from the blood to the cells by the high-affinity OCTN2 carnitine transporter in the cell membrane of the heart, skeletal muscle, and kidney (Figure 1) [67]. It should be noted that different types of carnitine transporters with low affinity and high capacity are present in hepatocytes.

1.2.2. Carnitine Palmitoyltransferase 2 (CPT2) and Acylcarnitine Translocase CAC (SLC25A20)

CAC (SLC25A20) transfers acylcarnitines across the inner mitochondrial membrane [68]. CAC forms a functional complex with carnitine palmitoyltransferase 2 (CPT2) in the inner mitochondrial membrane (Figure 1), leading to the transesterification of acyl groups from acylcarnitines to mitochondrial CoAs according to the reaction:
acylcarnitine + CoA-SH → acyl-CoA + carnitine
A high acylcarnitine concentration in the intermembrane space drives its translocation into the matrix [68]. The overall role of CPT1, CAC, and CPT2 in the transport of acyl-CoA into the mitochondrial matrix is presented in Figure 1. NO, H2S, nonenzymatic acetylations, β-lactam antibiotics, omeprazole (proton pump inhibitor), and heavy metals inhibit CAC [69,70,71,72,73,74,75,76]. PPARα and other transcription factors or transcriptional coactivators (estrogen receptors, PGC1α) activate the transcription of CAC, and polyphenols (antioxidants) increase the effectiveness of βOX. Statins, drugs lowering serum cholesterol concentration, and retinoic acid also increase CAC activity [77,78,79,80].

1.3. Mitochondrial β-Oxidation

A few years ago, the mitochondrial βOX was described by Hounten et al. in an excellent review [81]. Briefly, the first step of each βOX round is catalyzed by an acyl-CoA dehydrogenase (AD), producing trans-2-enoyl-CoA. In the next step, the hydration of a double-bond is catalyzed by enoyl-CoA-hydratase (ECH), and the following dehydrogenation by hydroxy-acyl-CoA dehydrogenase (HAD) leads to the production of 3-keto-acyl-CoA. The last step of the cycle is thiolysis. In each round of βOX, one FAD and NAD+ accept two electrons each and change into FADH2 and NADH, respectively. The electrons are then transferred to the mitochondrial respiratory chain, where oxidative phosphorylation (OXPHOS) occurs. The acetyl-CoA formed may enter the Krebs cycle (TCA) (mainly in the heart, kidney, and skeletal muscle) and other processes (for instance, ketogenesis in the liver) (Figure 1) [82,83]. The acyl-CoAs, which are shorter by two carbons compared to the initial substrate, enter the next round of βOX. The odd-chain FFAs (present in a small amount in human tissue) are degraded, like the even-chain acyl-CoAs, to several acetyl-CoAs (depending on FFAs). However, propionyl-CoA arises from the methyl end of the odd-chain acyl-CoA. Propionyl-CoA is converted via methylmalonyl-CoA to succinyl-CoA, metabolized in the TCA, or converted to glucose in the liver. The amount of propionyl-CoA formed from odd-chain FFAs is very small because the number of such FAs in the diet is relatively low.
Five ADs found in human cells are involved in the first step of βOX. Characteristics of ADs are presented in Table 2.

1.3.1. Oxidation of Long-Chain Acyl-CoA

Oxidation of long-chain acyl-CoA is catalyzed by one of three ADs: a) very-long-chain acyl-CoA dehydrogenase (VLCAD), b) acyl-CoA dehydrogenase DH-9 (ACAD9), and c) long-chain acyl-CoA dehydrogenase (LCAD). VLCAD oxidizes most LCFAs entering mitochondria. This enzyme, bound to the inner mitochondrial membrane, oxidizes C14:0–C22:0 acyl-CoA, although the preferred substrate is palmitoyl-CoA. The presence of an unsaturated bond in FFAs decreases the efficiency of the reaction catalyzed by this enzyme. PPARα is the most important VLCAD regulator, increasing its gene expression. Sirtuins (especially sirtuin 3) may also activate VLCAD through deacetylation [84,85,86,87,88].
ACAD9 is homologous to VLCAD and uses mostly unsaturated long-chain acyl-CoAs as substrates. It is abundant in the brain and liver. Despite the homology of this enzyme with VLCAD, neither enzyme can compensate for each other in their deficiency [85,89]. LCAD is localized in the mitochondrial matrix. It is mainly present in lung alveolar cells. LCAD knockout caused pulmonary surfactant (complex substances, mainly lipids, which play important functions in the alveoli and small airways) dysfunction and increased susceptibility to lung infections [86]. An in vitro investigation showed that some unsaturated and branched-chain acyl-CoA are the principal substrates for LCAD. This enzyme is exceptional among ADs because it tends to leak electrons, producing H2O2. Its function in organs other than the lungs has not been estimated [90].
Each AD uses FAD as an electron acceptor. Formed FADH2 has to be re-oxidized, so the electrons are translocated to a flavoprotein, electron-transferring flavoprotein (ETF), and then ETF-dehydrogenase transfers them into coenzyme Q (CoQ) in the OXPHOS system (Figure 1) [91,92].
The mitochondrial trifunctional protein (MTP) complex participates in the second step of LCFA oxidation. The MTP catalyzes three different reactions in a row. The MTP enzymatic activities are long-chain enoyl-CoA hydratase (LCEH), long-chain hydroxy acyl-CoA dehydrogenase (LCHAD), and long-chain β-ketothiolase (LCKAT). The MTP complex contains “a” and “b” subunits, forming an octamer bound to the surface of the inner mitochondrial membrane due to a strong interaction with membrane phospholipids [93,94]. Subunit “a” contains the enzymatic activities of hydratase and dehydrogenase, whereas subunit “b” contains thiolase activity. This enzymatic complex binds the enoyl-CoAs containing 6–16 carbons, but in the liver, its activity is the highest for C10 and longer acyl-CoAs. The final product of MTP activity is acetyl-CoA and acyl-CoA, which is shortened by two carbons and enters the next cycle of βOX [95].

1.3.2. Oxidation of Monounsaturated and Polyunsaturated Long-Chain Acyl-CoA

Oxidation of monounsaturated long-chain acyl-CoA requires an additional enzyme called 3,2-trans-enoyl-CoA isomerase (ECI), which catalyzes the following reaction:
trans-3-enoyl-CoA → trans-2-enoyl-CoA
ECI exists in two isoforms: ECI1 and ECI2. ECI1 is found in mitochondria only, whereas ECI2 is present in mitochondria and peroxisomes. ECI2 has a much higher affinity for LCFAs [96,97,98]. The studies on ECI isoforms were performed using enzymes isolated from rat liver [96] and the ECI1 knock-out mice model [97], and structural studies using X-ray scattering were performed for a human ECI2 isoform [98].
The βOX of polyunsaturated FAs requires a) ECI and b) 2,4-dienoyl-CoA reductase, which catalyzes the following reaction:
trans-2,cis-4-dienoyl-CoA + NADPH + H+ → tans-3-enoyl-CoA + NADP+
Formed tans-3-enoyl-CoA by 2,4-dienoyl-CoA reductase is converted to trans-2-enoyl-CoA by ECI, as presented above.

1.3.3. Oxidation of Medium-Chain Fatty Acids

In the first cycle of MCFA mitochondrial FAO, medium-chain acyl-CoA dehydrogenase (MCAD) catalyzes the initial step. It is a flavoprotein cooperating with ETF and ETF-dehydrogenase. MCAD is a homotetrameric protein localized in the mitochondrial matrix. It is abundant in the human heart, skeletal muscles, and liver [99,100]. The enzymes responsible for the subsequent reactions are not well-defined in humans. It is possible that human MTP participates in the oxidation of medium-chain enoyl-CoAs. However, it is not excluded that MCFAs, which translocate from the cytosol to mitochondria, might be activated and elongated, finally becoming the substrate for MTP [101].

1.3.4. Oxidation of Short-Chain Fatty Acids

The first step of SCFA degradation is catalyzed by short-chain acyl-CoA dehydrogenase (SCAD), a flavoprotein cooperating with ETF/ETF-dehydrogenase. Butyryl-CoA, formed from butyrate produced by gut microbiota, is the major substrate for SCAD, and the product is crotonyl-CoA [102]. SCAD is abundant in the liver, heart, and skeletal muscles. It is a matrix-localized homotetramer. In the liver and kidneys, SCAD also displays oxidase activity, but the significance of this feature is unresolved [103,104]. The other enzymes involved in short-chain acyl-CoA oxidation are crotonase (enoyl-CoA hydratase), medium-chain hydroxy acyl-CoA dehydrogenase, short-chain hydroxy acyl-CoA dehydrogenase (SCHAD), and medium-chain ketoacyl-CoA thiolase (MCKAT), and all those activities are localized in the mitochondrial matrix. Human crotonase uses crotonyl-CoA as a substrate. It is also involved in the metabolism of some amino acids. Crotonase is present in significant amounts in the liver, less in muscles and fibroblasts, and even less in the kidneys and spleen [105,106]. Hydroxyacyl-CoA dehydrogenase is a homodimer localized in the matrix, which produces acetoacetyl-CoA and NADH. The highest activity of this enzyme is present in the heart, muscles, liver, and pancreas [107]. MCKAT catalyzes the last step of short-chain FAO. The activity of MCKATs is present in the mitochondrial matrix, peroxisomes, and cytosol. MCKATs that are present in the matrix of human mitochondria have two main substrates: methyl-acetyl-CoA (metabolized into propionyl-CoA) and acetoacetyl-CoA (metabolized into two molecules of acetyl-CoA).

1.4. Peroxisomal FAO

In the liver, FAO takes place both in mitochondria and peroxisomes. However, under physiological conditions, peroxisomal FAO accounts for approx. 5% of total FAO in the liver [108]. Peroxisomal βOX differs significantly from mitochondrial βOX [109,110]. In mitochondria, acyl-CoA dehydrogenases transfer the electrons to ETF, which are subsequently transferred to the mitochondrial respiratory chain and reduce oxygen to water, producing energy (ATP) [82]. In contrast, peroxisome acyl-CoA oxidase 1 (ACOX1) reduces FAD, and electrons are transported directly from FADH2 to molecular oxygen, generating hydrogen peroxide (H2O2) [110]. CoA esters of straight-chain FAs (VLCFAs, LCFAs, PUFAs, and dicarboxylic acids) are preferred substrates for ACOX1, whereas ACOX2 is responsible for the oxidation of branched-chain FAs (BCFA) and the transformation of bile acid intermediates [111]. In addition, Ferdinandusse et al. identified a novel ACOX isoform, ACOX3, which is involved, similar to ACOX2, in the degradation of BCFAs [112].
The oxidation of LCFAs in peroxisomes stops at the level of MCFA-CoAs [110]. MCFA-CoAs can be hydrolyzed to FFAs by the peroxisomal thioesterases. Then, MCFAs, via the pore-forming proteins, leave the peroxisome and are transported to the mitochondria, where βOX is completed. The second way of MCFA oxidation uses carnitine and carnitine acyltransferase with specificity for short- and medium-chain acyl-CoA. Formed acylcarnitines are transported into mitochondria via the mitochondrial CAC [113]. It should be emphasized that peroxisomal FAO needs the participation of mitochondria not only for the oxidation of acetyl-CoA (formed from MCFA-CoAs) but also for the oxidation of NADH [110,114]. For a summary of mitochondrial and peroxisomal βOX, see Table 3.
It has been shown that during peroxisomal βOX (both dicarboxylic and monocarboxylic acids), free acetate is formed, which is preferentially exported from the hepatocyte and used as an energy substrate in other organs [113]. It has been postulated that acetate is formed from acetyl-CoA in a reaction catalyzed by acetyl-CoA hydrolase [92].

1.4.1. Peroxisomal α-Oxidation—Role in Phytol and Phytanic Acid Metabolism

The average Western diet contains approx. (a) 50–100 mg per day of phytanic acid, (b) 10–30 mg per day of pristanic acid, and (c) 10 mg per day of phytol [119]. Phytol mostly comes from nuts [120]. Phytanic acid and pristanic acid are derived primarily from lipids found in beef, dairy products, and fish. [119]. The phytanic acid present in the diet is derived mainly from phytol [121]. Phytol is widely distributed as a constituent of chlorophyll present in the green leaves of plants and trees [3]. Bacteria present in the rumen of ruminant animals cleave the phytol from the porphyrin ring of chlorophyll (the human alimentary tract cannot do this). The released phytol can be oxidized to phytanic acid in the ruminants [3]. Thus, it is clear that phytanic acid is present in meat and dairy products from grass-fed cattle or other ruminants. Phytanic acid can also be derived from vegetables (as phytol bound to chlorophyll) [122]. Moreover, phytyl FA esters are also present in the leaves of some plants, fruits, and vegetables. These compounds are hydrolyzed in the human gastrointestinal tract, providing phytol [123].
Subjects consuming products rich in phytol and phytanic acid oxidize these compounds via α-oxidation because BCFAs containing a methyl group in the 3-position (like phytanic acid) are not metabolized by βOX. First, phytol is oxidized to phytenal in the reaction catalyzed by alcohol dehydrogenase. Formed phytenal is oxidized by aldehyde dehydrogenase to phytenic acid, which in turn is converted to phytenoyl-CoA by acyl-CoA synthetase. In the reaction catalyzed by enoyl-CoA reductase, phytenoyl-CoA is converted to phytanoyl-CoA. Phytanoyl-CoA can also be formed from phytanic acid in the reaction catalyzed by acyl-CoA synthetase. Formed phytanoyl-CoA undergo α-oxidation to 2-hydroxyphytanoylo-CoA, catalyzed by phytanoyl-CoA 2-hydroxylase. This process requires 2-oxoglutarate and Fe2+, and O2. 2-hydroxyphytanoilo-CoA is converted with the participation of hydroxy acyl-CoA and aldehyde dehydrogenase to pristanic acid, which is activated to pristanoyl-CoA by acyl-CoA synthetase. Next, pristanoyl-CoA undergoes peroxisomal βOX to 4,8-dimethyl nonaoyl-CoA, which in turn is metabolized in mitochondria (Figure 2) [123].
Deficiency of the phytanoyl-CoA 2-hydroxylase impairs the conversion of phytanic acid to pristanic acid (2-methyl BCFAs) and leads to Refsum disease (type IV motor and sensory neuropathy) [124,125]. The only therapy available for that disorder is a diet low in phytanic acid.

1.4.2. Peroxisomes Are Essential for the Degradation of Dicarboxylic Acid Formed during ω-Oxidation in Microsomes

VLCFAs are also oxidized in microsomes via ω-oxidation. In humans, the first step of ω-oxidation is catalyzed by CYP (CYP4F2 or CYP4F3B). Omega-hydroxy-VLCFAs, formed by CYP4F2 or CYP4F3B, can be oxidized to ω-HOOC-VLCFA (dicarboxylic-VLCFA) by alcohol dehydrogenase and subsequently by aldehyde dehydrogenase. Formed HOOC-VLCFA is then oxidized by βOX in peroxisomes. Importantly, the βOX of HOOC-VLCFA is not affected in X-ALD (X-linked adrenoleukodystrophy) patients [2]. Thus, it has been suggested that the peroxisomal βOX of dicarboxylic-VLCFA (formed during ω-oxidation) can provide an alternative route of VLCFA oxidation in X-ALD patients (Figure 3) [2].

1.4.3. Peroxisomal FAO—Potential Role in the Utilization of Toxic FFAs

Peroxisomal βOX is necessary for the oxidation of VLCFAs (≥22 carbons), both saturated and mono- and polyunsaturated [110,113]. These FFAs need to be degraded not because of their role in providing energy but due to the toxic effect of their excessive accumulation (for instance, monounsaturated erucic acid C22:1, present in commonly used canola oil) [113,126]. The βOX of VLCFAs, notably C26:0 and longer-chain FFAs, occurs exclusively in peroxisomes [113].
Abnormalities in the biogenesis of peroxisomes are the cause of Zellweger syndrome. This rare familial disease is characterized by muscle weakness, hepatomegaly, and brain and kidney dysfunction. Goldfischer et al. reported that peroxisomes are absent in the liver and kidney of patients with this syndrome [127]. Consequently, significant amounts of VLCFAs and bile acid synthesis intermediates are accumulated in plasma [125,127,128,129].
Subfamily D of ABC transporters (ATP-binding cassette transporters) in mammals comprises four distinct proteins, namely ABCD1 (adrenoleukodystrophy protein), ABCD2 (adrenoleukodystrophy-related protein), ABCD3 (70 kDa peroxisomal membrane protein), and ABCD4 (peroxisomal membrane protein 69). Three of these, ABCD1-3, are localized solely in peroxisomes and mediate the uptake of substrates into the peroxisome for βOX [115].
ABCD1 and ABCD2 facilitate the transport of VLCFAs or their CoA derivatives into peroxisomes. Interestingly, ABCD1 has a higher specificity for saturated VLCFA-CoA. In contrast, ABCD2 prefers to transport PUFAs, such as C22:6-CoA and C24:6-CoA [130]. However, it is worth adding that the main substrate for ABCD2 in humans is still not completely defined [131]. The ABCD3 transporter is important in transporting branched chain acyl-CoA and bile acid intermediates, e.g., di- and tri-hydroxycholestanoyl-CoA (DHCA and THCA) [132]. Abcd genes are under complex regulation at the transcriptional level. The transcription of Abcd1, Abcd2, and Abcd3 genes is regulated by PPARα [133,134]. Leclercq et al. demonstrated that the hepatic expression of Abcd2 and Abcd3, but not Abcd1 and Abcd4, exhibits a high degree of sensitivity toward dietary PUFA intake [135].

1.4.4. Peroxisomal FAO Related to the Synthesis of Cholesterol and Phospholipids

Acetyl-CoA formed during FAO in peroxisomes can be used for synthesizing cholesterol and phospholipids (mainly plasmalogen) [136]. For instance, the first two steps of plasmalogen biosynthesis occur in peroxisomes from the acetyl-CoA derived from peroxisomal FAO [137]. Recent studies indicate that peroxisomal βOX stimulates cholesterol biosynthesis in the liver of diabetic mice [138]. Moreover, it has been reported that the inhibition of peroxisomal βOX suppresses cholesterol biosynthesis and consequently lowers plasma cholesterol concentration. Based on these data, the authors suggest that the upregulation of peroxisomal cholesterol biosynthesis related to βOX may contribute to diabetes hypercholesterolemia [138].

1.4.5. Peroxisomal FAO—Inhibition of Lipophagy

Lipophagy involves the encapsulation of lipid droplets into the autophagosome, which fuses with the lysosome, resulting in the hydrolysis of triacylglycerols catalyzed by lysosomal acid lipase A [110,139,140,141]. Peroxisomal FAO in the liver promotes hepatic steatosis by inhibiting lipophagy [141]. Supplied by FAO, acetyl-CoA is involved in the acetylation of Raptor, a component of mTORC1, a metabolic regulatory complex that inhibits autophagy [141].

1.4.6. Peroxisomal FAO—Regulation of Mitochondrial β-Oxidation

Peroxisomal βOX increases the cellular NADH/NAD+ ratio, which inhibits the SIRT1/AMPK pathway. The inhibition of that pathway leads to increased ACC activity. It causes elevation of malonyl-CoA levels in the cytosol, inhibiting CPT1 and the transport of LCFAs into mitochondria, decreasing mitochondrial βOX [110,142].

1.4.7. Peroxisomal FAO As a Process Associated with the Production of H2O2—An Important Signaling Molecule and Toxic Substance

As mentioned above, peroxisomal FADH2 formed during βOX is involved in H2O2 production. H2O2 is an important signaling molecule that regulates many cellular processes by modulating the activity of several proteins via cysteine oxidation [143]. Under physiological conditions, catalase converts most of the H2O2 formed during peroxisomal βOX to H2O and O2 [144]. However, when catalase activity is decreasing, for instance, during aging, part of H2O2 formed via peroxisomal βOX diffuses out the peroxisome (it is a relatively stable ROS) and may modulate the activity of redox-sensitive protein, which in turn triggers a complex network of signaling processes leading to regulation of (a) NF-ϰB activation, (b) E cadherin expression, (c) the secretion of matrix metalloproteinases, (d) mTORC activity, and (e) autophagy [144,145]. However, it is generally believed that reactive oxygen species (ROS) play a dual role. At physiological conditions, they are required for many signaling processes, affecting proliferation, differentiation, and aging, but there are also toxic byproducts of aerobic metabolism, including products of FFA oxidation [146]. H2O2 can be converted to highly reactive hydroxyl radicals, causing damage to proteins, lipids, and DNA, leading to many diseases, including atherosclerosis, cancer, diabetes, and rheumatoid arthritis [147]. Thus, it is tempting to speculate that microsomal βOX, via H2O2 production, may affect aging processes and aging-related diseases.

1.4.8. Microsomal Fatty Acid ω-Oxidation

Under physiological conditions, FA ω-oxidation accounts for no more than 10% of total fatty oxidation in the liver [2]. In this process, the terminal methyl group (ω carbon) of FFAs is oxidized to the carboxyl group. The first step of ω-oxidation is catalyzed by the CYP family present in the microsome (including CYP4F2 and CYP4F3B), which requires NADPH and O2. Formed ω-hydroxy-FFAs are oxidized to ω-oxo-FFAs by cytosolic alcohol dehydrogenase. Finally, ω-oxo-FFAs are oxidized by cytosolic aldehyde dehydrogenase to carboxy-FFAs. Formed carboxy-FFAs (dicarboxylic-FAs) can be excreted into the urine or transported into mitochondria or peroxisomes, where they are metabolized via βOX. It should be noted that phytanic acid (described above) can also be oxidized via ω-oxidation [2]. Moreover, it has also been postulated that microsomal ω-hydroxylase is involved in (a) the synthesis of ω-hydroxylated arachidonic acid in the human liver and kidney, which regulates cardiovascular function (as vasoconstrictor), (b) ω-oxidation, and consequently the inactivation of leukotriene B4 (LTB4) in human leukocytes, and (c) the ω-oxidation of MCFAs and some xenobiotics [2].

2. The Function of FAO in Selected Organs

2.1. Liver

In the liver, FAO takes place in mitochondria and peroxisomes [148]. In a condition of low dietary carbohydrate supply or a prolonged fasting state, the activity of FAO increases significantly in the liver mitochondria, which is associated with a significant amount of energy production. In the liver, FAO is also the predominant source of acetyl-CoA, the substrate for ketone bodies (KBs) synthesis, and an important substrate for cholesterol synthesis, II phase detoxication, protein acetylation, and the synthesis of many other compounds, including N-acetylglutamate (NAG) synthesized by N-acetylglutamate synthase [149,150,151,152,153].
When intensive FAO occurs in the liver, acetyl-CoA and acetoacetyl-CoA (products of FAO) are used in the mitochondrial matrix to synthesize KBs. Acetoacetyl-CoA can also be formed by condensing two acetyl-CoA molecules in a reaction catalyzed by acetyl-CoA acetyltransferase 1. Subsequently, mitochondrial 3-hydroxy-3-methylglutaryl-CoA synthase 2 (HMGCS2) catalyzes the condensation of acetoacetyl-CoA and acetyl-CoA, generating 3-hydroxy-3-methylglutaryl-CoA (HMG-CoA), which is cleaved by HMG-CoA lyase (HMGCL), yielding acetoacetate (AcAc) and acetyl-CoA. AcAc can be reduced to D-β-hydroxybutyrate (BHB) by D-β-hydroxybutyrate dehydrogenase 1 (BDH1). In addition, AcAc can undergo spontaneous decarboxylation to acetone [82,154]. The plasma concentration of KBs under physiological conditions in humans is low (0.05–0.1 mmol/L) and significantly rises during prolonged starvation, ketogenic diet consumption, or insulin deficiency to 5–8 mmol/L and even 20 mmol/L in severe diabetic ketoacidosis [154]. Of the total pool of circulating KBs, BHB accounts for about 70% and is the most abundant [152,154]. The BHB to AcAc synthesized ratio is proportional to the mitochondrial NADH/NAD+ equilibrium [155]. The formed BHB and AcAc are alternative energy sources for extrahepatic tissues, particularly skeletal muscle, heart, kidneys, and the nervous system during diminished glucose availability [154,155]. The main regulatory steps of ketogenesis include (a) the availability of FFAs to hepatocytes, (b) the transport of acyl-CoA into mitochondria, and (c) HMGCS2 activity, a rate-limiting enzyme in ketogenesis. HMGCS2 is regulated at the level of gene transcription and by post-translational modifications [154]. The increased level of ketogenesis also occurs in subjects on a ketogenic diet and patients with severely uncontrolled diabetes [151,152]. KBs produced during ketogenesis are AcAc, BHB, and acetone [152].

2.1.1. Mitochondrial FAO As a Regulator of Gluconeogenesis

In carbohydrate-deficient states, gluconeogenesis is the primary source of blood glucose. The stimulation of gluconeogenesis is attributed to mitochondrial FAO in connection with the production of acetyl-CoA and NADH. Acetyl-CoA is an allosteric activator of pyruvate carboxylase, a key gluconeogenic enzyme, whereas NADH is used to form 3-phosphate glyceraldehyde (precursor of glucose) from 1,3-bisphosphoglycerate [156]. Furthermore, the acetyl-CoA is an activator of pyruvate dehydrogenase kinase, which phosphorylates and consequently inhibits the pyruvate dehydrogenase complex (PDC), inhibiting the conversion of pyruvate into acetyl-CoA and further into the TCA [155,157]. Accumulating pyruvate can be converted by pyruvate carboxylase to oxaloacetate, a glucose precursor.

2.1.2. Mitochondrial FAO As a Source of Acetyl-CoA for Protein Acetylation

Protein acetylation is a reversible post-translational modification of proteins, which involves the transfer of the acetyl group from acetyl-CoA to the ε-amino group of lysine [150]. Acetylation is catalyzed by lysine acetyltransferase using acetyl-CoA as one of the substrates (the second substrate is a non-acetylated protein). Acetylation can also occur non-enzymatically, and this process increases with increasing pH [150]. The acetyl-CoA necessary for acetylation is formed during mitochondrial βOX. It was shown that the hyperacetylation of liver protein depends on βOX since mice deficient in βOX cannot increase the acetylation of proteins [158]. Deacetylation is catalyzed by lysine deacetylase [150]. Protein acetylation and deacetylation are important regulatory mechanisms that modulate more than 2000 proteins (Figure 4) [159]. Interestingly, enzymes regulated by acetylation/deacetylation include FAO enzymes (LCAD and MCAD). LCAD is acetylated and consequently inactivated at lysine 42. Deacetylation and, consequently, the activation of LCAD is catalyzed by SIRT3—an NAD+-dependent protein deacetylase [160]. MCAD is acetylated and inactivated at lysine 318 and 322 [161]. It should be noted that liver mitochondrial enzymes regulated by acetylation and deacetylation are also (a) enzymes involved in ketogenesis and (b) enzymes involved in urea synthesis [162,163,164,165].

2.1.3. The Potential Role of Mitochondrial FAO in the Regulation of Ureagenesis

Human adults produce approximately 1 mol (approx. 17 g) of toxic ammonia daily, most of which, via carbamoyl phosphate, is converted to nontoxic urea (at physiological concentrations) in the urea cycle [166]. It is well known that the synthesis of urea in humans and most animals requires, among others, four molecules of ATP per one formed molecule of urea as a source of energy and NAG as a positive allosteric activator of carbamoyl phosphate synthetase I (CPS1), a key regulatory enzyme in the urea cycle [167]. In theory, mitochondrial βOX may be involved in the production of both ATP and NAG. Indeed, some data indicate that an increase in liver FAO was associated with increased NAG level [168]. Therefore, stimulation of the liver FAO may likely increase acetyl-CoA level, a substrate for NAG synthesis and a key activator of CPS1. Thus, one can conclude that liver mitochondrial FAO plays an important role in the regulation of ureagenesis. In this manner, liver FAO appears necessary to prevent the accumulation of free ammonia, a neurotoxic compound, in blood and other tissues, including the brain. This conclusion is confirmed by published data, indicating that the defect of liver mitochondrial βOX is associated with hyperammonemia [169].

2.1.4. The Potential Role of Mitochondrial FAO in Phase II Detoxication

The liver requires a lot of ATP to perform detoxication of xenobiotics and endogenously produced substances (for instance, the conversion of ammonia to urea described above). ATP is needed mainly to synthesize uridine diphosphate glucuronic acid, glutathione, 3′-phosphoadenosine-5′-phosphosulfate, and S-adenosylmethionine, compounds playing a key role in phase II of detoxication. Energy can be provided by βOX. Moreover, acetyl-CoA in phase II detoxication can be formed during liver mitochondrial βOX. N-acetyl transferases (NATs), also known as arylamine N-acetyl transferases, play an important role in the phase II detoxication of xenobiotics, including drugs and detoxication [153]. In humans, the acetylation of xenobiotics is catalyzed by NAT1 and NAT2. These enzymes are responsible for transferring the acetyl group from acetyl-CoA to convert aromatic amines to aromatic amides or hydrazines to hydrazides [153]. It should be noted that in humans, acetylation is an important route of biotransformation for many arylamine and hydrazine drugs, as well as for the biotransformation of carcinogens present in the diet, cigarette smoke, and environment.

2.1.5. Hepatic Manifestations of FAO Disorders (FAOD) Caused by Genetic Defects

One of the frequent manifestations in patients with FAOD is liver dysfunction. It is mainly associated with deficiencies of VLCAD, LCHAD, MCAD, CPT1, CPT2, and CAC [82,170]. Symptoms are triggered by extended fasting, exercise, fever, sepsis, and other metabolic stress causes. Liver dysfunction resulting from abnormal FAO usually appears early in life. It may include hypoketotic hypoglycemia or liver dysfunction resulting from hepatocyte damage, including Reye syndrome. Hepatic symptoms may also occur later in life [170]. Hypoglycemia in patients with FAOD occurs when glycogen stores are depleted, possibly due to increased peripheral glucose uptake. It may result from impaired energy production from FFAs and the reduced synthesis of KBs by the liver [171]. It may also be a consequence of reduced hepatic gluconeogenesis [172]. FAOD can lead to the sudden death of newborns, mainly due to the limited glycogen reserves and high metabolic rate [171]. Most of the liver damage observed in FAOD is due to the toxic effects of accumulating FFAs and their carnitine derivatives. These toxic effects are related to (a) the inhibition of the mitochondrial respiratory chain and energy deficiency, (b) increasing reactive oxygen species (ROS) formation, and an imbalance in calcium homeostasis, leading to mitochondrial damage and further apoptosis or necrosis of cells [171,173]. Symptoms of Reye-like classified hepatic-presenting FAOD include hepatic encephalopathy, hepatomegaly, hyperammonemia, and microvesicular steatosis of the liver [170].

2.2. Heart and Skeletal Muscles

The heart requires enormous quantities of ATP to maintain its contraction capacity and ion homeostasis. ATP and phosphocreatine stored in cardiomyocytes ensure the heart works properly for only a few seconds. Therefore, ATP must be constantly synthesized (from ADP and Pi), mainly through oxidative phosphorylation, providing approx. 95% of ATP, with anaerobic glycolysis providing the rest. A healthy subject’s heart is metabolically flexible and readily shifts between energetic substrates [174]. In the resting state, βOX contributes to the synthesis of approx. 50–70% of ATP. The remaining is mainly provided by glucose oxidation. KBs (mainly BHB) are the third supplier of ATP (10–15%), whereas amino acids contribute 1–2% for energetic purposes [175]. During exercise or myocardial stress, lactate may also be an important fuel for the myocardium [176].
Significant changes in heart mitochondrial energy metabolism are related to pathological conditions. In diabetes, the ratio of FAO to glucose oxidation is increased due to elevated FAO and lowered glucose oxidation [177]. The inhibition of glucose utilization by FFAs occurs at multiple levels, including glucose uptake by cells, the rate of glycolysis, and mitochondrial oxidation. Recent research suggests that cardiac metabolic overload with oleate or palmitate leads to increased global protein acetylation, which inhibits glucose transporter type 4 (GLUT4) translocation to the plasma membrane and consequently inhibits glucose uptake [178]. Lipid abnormalities leading to atherosclerotic plaque formation in the vascular wall also induce a remodeling of the energy metabolism in cardiac myocytes toward accelerated FFA and branched-chain amino acid oxidation. Redirection toward FAO increases the oxygen cost of ATP formation and may become maladaptive and reduce myocyte survival rates under acute oxygen deprivation [179]. The administration of trimetazidine (a competitive inhibitor of LCKAT), etomoxir, or perhexiline (inhibitors of CPT1) resulted in a cardioprotective effect in humans with heart failure (HF), probably through the inhibition of FAO and an increase in glucose oxidation [174,180]. In general, these data suggest that reduced FAO might improve cardiac function under pathological conditions.
However, the downregulation of LCAD or MCAD in patients with HF and animals during HF progression was detected. Moreover, impaired FAO contributes to the progression of HF by altering cardiac energy metabolism after myocardial infarction [181]. Thus, the problem of whether a reduction in FAO improves or worsens cardiac function is still an open question.
Inconsistent results have also been reported regarding the level of malonyl-CoA (as a natural inhibitor of FFA oxidation) and its role in cardiac function. The inhibition of MCD, increasing the malonyl-CoA level (inhibitor of CPT1, and consequently FAO), improved cardiac function by increasing cardiac output. The promising results of MCD inhibition were associated with the reduced production of protons due to enhanced coupling between glycolysis and glucose oxidation [182]. However, ACC inhibition, resulting in a decrease in the malonyl-CoA level, which stimulates the oxidation of FFAs, was also associated with a cardioprotective impact in the failing mouse heart [183].
Animal studies showed that increased FAO (caused by ACC2 deletion) did not induce cardiac dysfunction [184]. In addition, it was demonstrated that increased FAO in the heart protects against cardiomyopathy in chronically obese mice [183]. However, a strong correlation between decreased cardiac efficiency and an over-dependence on FAO has been reported in ob/ob mice and obese humans [185,186].
Increased cardiac FAO has been considered to cause elevated ROS production in mitochondria and subsequent oxidative damage of mitochondria, contributing to cardiac dysfunction in obese rodent models [187,188]. The molecular mechanisms responsible for FAO-induced lipotoxic cardiomyopathy are also unclear [184]. Several pathogenetic pathways have been proposed, such as mitochondrial dysfunction and oxidative stress, ER stress, and apoptosis induced by toxic lipids.
Levels of acyl-CoA are reduced in failing human hearts and hypertrophic mouse hearts. The heart-specific ACSL1 overexpression in mice causes an increase in acyl-CoA levels and a stable turnover of TAG with the preservation of all cardiac functions after pressure overload surgery. Therefore, it was suggested that therapies aimed at enhancing or mimicking the effects of ACSL1 could positively impact the treatment of chronic HF [189].
Cardiac dysfunction due to inborn errors in LCHAD, MTP, neonatal CPT2, VLCAD, and MCAD is the most common [190,191]. This FAOD may manifest in the neonatal period with severe symptoms, including cardiomyopathy, hepatic dysfunction, and hypoketotic hypoglycemia.
Patients with FAOD may develop hypertrophic cardiomyopathy due to an inadequate energy supply to the heart and the subsequent inefficient contraction [170]. Arrhythmias in FAOD patients are often multifactorial but mainly occur as LC-FAO defects. Conduction disturbances and atrial tachycardia were detected in patients with CPT2, CAC, and LCHAD/MTP deficiency [192]. Ventricular tachycardias were observed in patients with FAO deficiency [193]. It is critical to quickly and correctly identify significant signs and symptoms in patients with FAOD to manage metabolic decompensation and reduce possible comorbidities. Cardiac arrhythmias and hypoglycemia are often observed in the early postnatal period and may lead to sudden infant death syndrome. Therefore, inborn errors of FAO should be considered in all instances of sudden unexplained death [170]. In infancy and early childhood, FAOD may manifest as cardiac, skeletal muscle, and liver dysfunction and may also cause fasting or exercise-induced hypoketotic hypoglycemia, Reye-like syndrome, cardiomyopathy, and recurrent rhabdomyolysis [190]. Muscular symptoms, especially rhabdomyolysis and cardiomyopathy, are most common in adolescents or adults [194].
Heart failure associated with FAO deficiency is difficult to treat. Moreover, available treatments need to address the fundamental pathologies of LC-FAODs. Using medium even-chain triacylglycerols (MCT oil), which provided the MCFA source (mainly octanoate), did not eliminate symptoms of LC-FAO defects due to a deficit of TCA intermediates [190]. Triheptanoin (UX007, Ultragenyx Pharmaceuticals) is a triacylglycerol composed of seven carbon (C7:0). It was reported that the oral administration of triheptanoin resulted in a significant and rapid beneficial effect on cardiac function in children with various genetic FAO disorders (VLCAD, MTP, LCHAD, or CAC deficiency) [195]. Vockley et al. demonstrated after a long-term study that triheptanoin treatment was associated with significant improvements in glucose homeostasis and cardiomyopathy. Moreover, episodes with rhabdomyolysis were also reduced but with less effect than the other symptoms, which may suggest different pathophysiologic mechanisms that require additional therapy [196,197].
FAODs with skeletal myopathy occur most frequently in LCHAD, MTP, VLCAD, and CPT2 defects. Lack of energy production during the FAO process in skeletal muscles results in fatigue, which manifests as myalgia, muscle weakness, myoglobinuria, physical intolerance, and episodes of rhabdomyolysis. Myopathy usually begins due to excessive endurance exercise, anesthesia, or a viral illness in adolescents or adults but can also appear earlier. A significant deficiency of ATP in muscle cells leads to rhabdomyolysis, which, consequently, causes the release of myoglobin into the extracellular fluid and circulation [190]. It was demonstrated that bezafibrate, a PPARα agonist, might reduce rhabdomyolysis episodes in patients with CPT2 deficiency [198]. However, a different study demonstrated no beneficial effect of bezafibrate on FAO or physical ability [199]. Due to the absence of highly effective therapies to prevent rhabdomyolysis associated with FAO, patients with these disturbances should reduce prolonged and intense physical activity.
Increased skeletal muscle FAO has been proposed as a potential mechanism leading to impaired muscle insulin sensitivity [200]. Gavin and colleagues revealed that patients with poorly controlled type 2 diabetes (T2D) have elevated incomplete skeletal muscle FAO compared with well-controlled T2D patients [201]. Moreover, incomplete FAO was inversely related to muscle insulin sensitivity and glycemic control. The experiment also indicated that elevated HbA1c is associated with the upregulation of FAO gene expression in the skeletal muscle of T2D patients. Lipid overloading promotes incomplete FAO, increasing acylcarnitine levels in T2D patients’ plasma, possibly resulting in insulin resistance.
FAO is also dysregulated in the skeletal muscles of obese individuals. Several studies comparing metabolism in the muscles of obese and lean individuals demonstrated that in obesity, the skeletal muscle metabolic capacity is primarily involved in FA esterification and storage rather than oxidation [202,203]. In the skeletal muscle of obese women, maximal CPT1 activity was decreased by 27–35% compared to lean women. Moreover, the ratio of muscle CPT1 activity to FABPm protein in obese individuals was half the level detected in lean individuals [204]. This may suggest that in obesity, FAs can be taken up from plasma but cannot be further used as an energy source due to the muscle-reduced capacity for FA oxidation. Aerobic exercises seem appropriate to improve FAO and lipid metabolism in healthy and insulin-resistant obese individuals [203].

2.3. Kidney

Removing waste from the blood, reabsorbing glucose and other nutrients, regulating the balance of electrolytes and fluid, maintaining acid-base homeostasis, and regulating blood pressure by the kidney requires the continuous synthesis of ATP. FFAs serve as key substrates for energy production in the kidney [205]. Low βOX may contribute to the development and progression of kidney diseases due to low ATP levels and the excessive accumulation of triacylglycerols, leading to cellular lipotoxicity and the development of tubulointerstitial fibrosis [206,207,208]. The proximal tubule cells prefer FAO over glycolysis as a process of synthesizing ATP and display low metabolic flexibility between FAO and glycolysis, which make these cells more sensitive to acute and chronic hypoxia [209,210]. In contrast, the distal tubule cells are less susceptible to ischemic injury and nephrotoxins because they may switch from FAO to glycolysis during hypoxic/ischemic conditions [210].
The system of delivering FFAs to kidney cells is generally similar to other organs (presented above). Briefly, FFAs can be taken up by the proximal tubular cells by special FFA transporters (CD36, FABPs, FATPs) or reabsorbed from the glomerular filtrate by the endocytosis of receptor-mediated FA-bound albumin [210,211].
The downregulation or deficiency of CPT is crucial to impaired FAO in experimental models of acute kidney injury or diabetic nephropathy [210,212,213]. It has been shown that impaired lipid metabolism may be linked directly to kidney fibrosis [212,214]. Usually, kidney fibrosis is associated with the transforming growth factor (TGF-β) and is the final pathological process of any ongoing chronic kidney disease (CKD) or maladaptive repair. The changes in CPT1 expression significantly ameliorated FAO metabolism in the kidney [212]. Patients with CKD present decreased activity of CPT1 and an increased accumulation of short- and middle-chain acyl-carnitines due to impaired FAO. Therefore, strategies that can improve the mitochondrial structure and function, overcome the negative effect of TGF-β on the oxygen consumption rate, and promote tubular epithelial cell differentiation are postulated as potent therapeutics for kidney fibrosis in CKD [212,215]. In general, TGF-β takes part in many physiological and pathological processes, including (a) angiogenesis, (b) apoptosis, (c) the division of mesenchymal cells, (d) the regulation of the synthesis and the degradation of extracellular matrix protein. At the molecular level, TGF-β1 inhibits the expression of CPT1 and decreases FFA catabolism. Moreover, TGF-β1 also represses the synthesis of mRNA encoding the upstream regulators of CPT1, namely PPARα and PPARγ coactivator-1α (PGC1α) [216,217]. Genome-wide transcriptome studies revealed that enzymes and regulators of FAO are reduced in the kidneys of patients with CKD and experimental models of kidney fibrosis [217]. Mice with kidney injury treated with etoxomir (a specific inhibitor of CPT1) display a higher expression of fibrosis markers [218]. In addition, treating mice with C75, a synthetic compound that increases CPT1 activity, decreases the apoptosis rate in the kidney [217]. The above-presented data suggest that CPT plays a key role in kidney physiology and pathology.
It has been postulated that restoring FAO by regulating the level or activity of PPARα and TGF-β may improve the treatment of kidney disorders [219]. PPARs and PGC1α are the critical transcription factors/coactivators that regulate the expression of proteins involved in the uptake and oxidation of FFAs [220]. The administration of fenofibrate, the agonist of PPARα, strongly induces the expression of genes encoding FAO enzymes (Cpt1, 2 and Acox1, 2). Mice with kidney insufficiency injected with fenofibrate demonstrated a decreased expression of caspase 3, a reduced apoptosis rate, reduced fibrosis, reduced kidney injury, and improved renal function. This suggests that fenofibrate treatment restores FAO-related enzyme expression and may prevent lipid metabolism abnormalities in kidney diseases [217,220]. The protective effect of Wy-14643 (the PPARα ligand) was also demonstrated in cisplatin-induced renal failure. Cisplatin causes a significant reduction in proximal tubule FAO. PPARα ligands prevent acute tubular necrosis by ameliorating the cisplatin-induced inhibition of two distinct metabolic processes, MCAD-mediated FAO and PDC activity [219,221]. Also, the ketogenic diet enhanced FAO in mice with kidney fibrosis, reducing fibrosis in this organ [222]. Overall, βOX provides enough energy to support various kidney functions and ensures the kidney’s structural integrity [223].

2.4. Lungs

Recent studies indicate that βOX can also play an important role in pulmonary fibrosis, especially idiopathic pulmonary fibrosis (IPF), a fatal fibrotic disorder of unknown etiology [224]. Increased activity of FAO was observed in IPF lungs, which suggests that βOX can be involved in fibrinogenesis, mainly via macrophage activation [225]. Furthermore, βOX provides ATP, which is believed to promote macrophage M2 polarization, which plays a key role in fibrogenesis [226]. It has also been shown that macrophage CD36, involved in FFA transport, plays an important role in fibrogenesis since the loss of CD36 inhibits lung fibrosis [227]. Overall, the data presented above indicate that FAO can play an important role in developing IPF.

2.5. Enterocytes and Colonocytes

Glutamine and glutamate are the main energetic substrates for enterocytes. However, enterocytes can also oxidize FFAs entering the cells from the plasma and intestinal lumen. FFAs derived from the intestinal lumen (directly derived from dietary lipids, mainly TAG) provide more energy to enterocytes (approx. 60%) than FFAs derived from the plasma (approx. 40%) [228]. A high-fat diet significantly induces FAO in enterocytes. However, when animals are fed a high carbohydrate diet, FFAs are not an important energy source for enterocytes. It has been proposed that in addition to energy production, FAO in the small intestine (enterocytes) could be a sensor that affects eating behavior [228]. However, further studies are required to confirm this suggestion.
Colonocytes mainly oxidize SCFAs, including acetate, propionate, and butyrate, which are produced by gut microbiota. Butyrate is the main energy source of colonocytes and uses more than 70% oxygen for butyrate oxidation [229]. Any impairment of SCFA oxidation leads to a disturbance in colonocyte function. For instance, it has been shown that reducing SCFA oxidation by ibuprofen (a nonselective and nonsteroidal anti-inflammatory drug) may cause an ulcerative [230].

2.6. βOX in Other Organs/Tissues/Cells

2.6.1. Adipocytes

It was suggested that increased FAO in adipocytes might be a promising therapeutic strategy for chronic inflammatory diseases, including obesity and T2D [231]. An experiment with chickens revealed that fasting rapidly increases FAO in white adipose tissue (WAT) by upregulating the expression of genes involved in this process. Enhanced oxidation precedes the high level of FFAs in serum, indicating that FAO is induced at the early stages of lipolysis. Therefore, it may act as an adaptive response to elevated intracellular FFA levels in adipocytes [232]. Gonzalez-Hurtado et al. demonstrated that FAO is critical not only for adipose bioenergetics but also for the browning of WAT and BAT survival under acute thermogenic activation and during periods of BAT quiescence [233].

2.6.2. Brain

It is generally believed that glucose and KBs during starvation, but not FFAs, are energy substrates for the brain. It has been suggested that a lack of active βOX in neurons may protect these cells against excessive ROS production and hypoxia [234]. As was already discussed, both processes’ intensity (excessive ROS production and hypoxia) increase in the cells oxidizing FFAs. However, some recent studies indicate that βOX can provide up to 20% of the energy used by the entire rat brain [235]. Moreover, it has been shown that FFAs can be transported through the blood–brain barrier and oxidized by astrocytes [236,237,238,239]. Acetyl-CoA, formed as the end product of the βOX in astrocytes, can be used as a substrate for KB production. Formed KBs can be transported to neurons, where they serve as an energy substrate [240]. Additionally, FFAs that are peroxidized in hyperactive neurons can be transported to astrocytes and stored in lipid droplets or oxidized in βOX [241]. Our recent review extensively discussed the function of FAO in the brain [242].

2.6.3. Endothelium

Endothelial cells (ECs) produce more than 85% of the energy needed in anaerobic glycolysis [243]. However, it was demonstrated that in proliferating ECs, acetyl-CoA produced during βOX contributes a significant portion of the carbons required for the TCA intermediates—precursors of substrates necessary for de novo dNTP synthesis [243,244]. Furthermore, Kalucka et al. demonstrated that quiescent ECs upregulate FAO enzymes to maintain the TCA for redox homeostasis through NADPH by isocitrate dehydrogenase 2 (IDH2) and ME3 [245]. Summing up, one can say that βOX takes place in ECs and plays an important role in some processes, including de novo dNTP synthesis and maintaining redox homeostasis.

2.6.4. Placenta

A very early work from our department demonstrated palmitoyl–carnitine oxidation in mitochondria isolated from the human term placenta [246]. Later, it was demonstrated that FAO enzyme activity in the human placenta was higher early in gestation and lower in term [247,248]. Moreover, it has been shown that a deficiency in FAO may result in placental dysfunction, leading to gestational complications [249]. An increased expression of genes associated with βOX has been observed in the human placenta in pre-eclampsia [250]. Recent studies also indicate the important role of βOX in the placenta for normal fetal development, although the expression of genes related to βOX in the term human placenta is about 20 times lower than in the liver [251,252]. Recently published data indicate that human placental FAO can be inhibited by high glucose concentration in pregnant women with diabetes. Based on these data, it has been suggested that inhibiting FAO can lead to an increase in lipid transfer to the fetus and, consequently, excessive fetal growth [253]. The results presented above suggest that FAO plays an important role in developing the human placenta and the normal course of pregnancy.

2.6.5. Peripheral White Blood Cells

Glycolysis and glutaminolysis provide enough ATP for the normal function of peripheral white blood cells [254]. However, it has been shown that FFAs are also oxidized by human white blood cells. Moreover, it has been demonstrated that βOX is not significantly affected by sex or acute exercise, but genetic factors play a significant role in determining the level of FAO [255]. Interestingly, in healthy subjects’ peripheral blood cells, specific carnitine esters (different from other tissue) are accumulated [256]. Accordingly, different amounts and patterns of acylcarnitine esters were found in patients with defects of βOX [256,257]. It may have practical significance since analyzing βOX intermediates in peripheral blood cells may allow the identification of FAO defects.

2.6.6. Steroidogenic Cells

It has been shown that FAO is also active in steroidogenic tissues. Moreover, it has been demonstrated that FAO activity in steroidogenic cells is regulated by translocator protein (TSPO), also known as the peripheral benzodiazepine receptor [258]. This protein is located in the outer mitochondrial membrane, and its depletion leads to increased (a) FFA uptake by mitochondria, (b) FAO, and (c) ROS production. TSPO depletion in cells induces a shift in substrate oxidation from glucose to FFAs for energy production. The authors suggest that TSPO can play an important role in modulating FAO not only in steroidogenic tissue but also in cells active in lipid storage and metabolism [258].

2.6.7. Osteoclast

Bone formation by osteoblasts and bone resorption by osteoclasts play a crucial role in skeletal remodeling. These processes require a large amount of ATP produced by glucose, FA, and amino acid oxidation [259,260]. Several years ago, it was shown that active osteoclasts exhibit HAD activity [261], suggesting that βOX takes place in these cells (active osteoclast). Some data indicate that βOX is involved in osteoclastogenesis [262]. It has also been shown that the cell membrane of osteoclast possesses transporters involved in LCFA uptake [263,264]. Moreover, it has been reported that the high energy state of an active osteoclast (osteoclast in the active bone resorption state) could be supported by lipid catabolism [265].
Recent studies showed (a) a significant increase in LCFA oxidation during osteoclast differentiation. This was associated with increased mRNA and protein levels of enzymes involved in βOX [266]. Thus, mitochondrial FAO is important for normal osteoclast formation and function. Based on these data, one can conclude that FFAs are key energy sources necessary for bone remodeling, and their inhibition may lead to a disturbance in osteoclast formation and function [266]. For instance, some authors suggest the role of osteoclast energy metabolism in the development of osteoporosis [260]. Very recently, the upregulation of CPT1A and increased FAO in osteoclast precursors of patients with rheumatoid arthritis has been shown [267]. Moreover, enhanced FAO influences osteoclastogenesis and promotes cell–cell fusion during osteoclast maturation. In contrast, the knockdown of the CPT1A gene or the inhibition of CPT1A activity by etomoxir (pharmacological inhibitor of CPT1A) blocked osteoclastogenesis. Based on these data, the authors conclude that increasing FAO in osteoclast precursors participates in joint destruction in patients with rheumatoid arthritis [267]. The results presented above indicate that FAO plays an important role in providing energy for osteoclastogenesis and, consequently, skeletal remodeling. Disturbance in FAO in active osteoclasts might lead to osteoporosis, whereas osteoclast precursors lead to joint destruction in rheumatoid patients.

2.6.8. Pancreatic β-Cell

FAO in the pancreatic β-cell is involved in the regulation of insulin secretion [268]. Many years ago, it was shown that FFA catabolism via mitochondrial βOX is an important energy source for pancreatic β-cells [269]. It is also well known that energetic substrates, mainly glucose, regulate insulin secretion by pancreatic β-cells. However, FFA and amino acids also stimulate glucose-induced insulin secretion [270]. Glucose metabolism plays a crucial role in the stimulation of insulin secretion by pancreatic β-cells. It is generally believed that glucose metabolism in pancreatic β-cells (via a sequence of the following events: an increase in the ATP/ADP ratio → closure of the ATP-sensitive K channels → the cell membrane depolarization and opening of voltage-sensitive Ca2+ channels) raises intracellular Ca2+ concentration and triggers exocytosis of insulin-containing granules [271]. FFAs have also been shown to stimulate glucose-induced insulin secretion by pancreatic β-cells over short-time exposure [271]. However, the mechanism by which FFA may stimulate insulin secretion by pancreatic β-cells is still unknown. By combining several data, Prentki et al. created a comprehensive model called the “trident model of pancreatic β-cells lipid signaling” to explain the role of FFAs in stimulating insulin secretion by pancreatic β-cells [272]. In a nutshell, the model takes into account three interdependent processes. Two of them are strictly related to the intracellular metabolism of FFAs and the third is related to membrane FFAR (the free fatty acid receptor present in pancreatic β-cells) activation. The first intracellular process proposed in this model is associated with elevated levels of LC-CoA in pancreatic β-cells. It occurs via a sequence of the following events: glucose metabolism (glucose → → pyruvate → acetyl-CoA → malonyl-CoA), which leads to an increase in malonyl-CoA, which inhibits CPT1 and consequently slows down FAO. As a consequence of FAO inhibition, an intracellular increase in LC-CoA takes place. LC-CoA regulates many pancreatic β-cell functions, including (a) the activation of some types of protein kinase C (PKC), which plays a crucial role in glucose-stimulated insulin secretion by pancreatic β-cells, (b) the modulation of ion channels (also involved in insulin secretion), the modulation of protein acylation channels (also involved in insulin secretion), and (d) the regulation of some gene transcriptions [271]. The second intracellular process of the trident model is associated with glucose metabolism, which (a) promotes FFA esterification by providing glycerol 3-phosphate and malonyl-CoA (as a physiological regulator of CPT1; see discussion above) and lipolysis (providing FFA), leading to an increase in intracellular DAG and phospholipids levels in pancreatic β-cells. Increased intracellular DAG and Ca2+ lead to insulin secretion by pancreatic β-cells mediated by PKC [271]. The third mechanism of the postulated trident model is associated with the binding and activation of FFAR1 (GPR40) by FFAs, which causes an increase in intracellular Ca2+, leading to insulin secretion by pancreatic β-cells. As mentioned, all these complex processes (two intracellular and one extracellular) stimulate insulin secretion by pancreatic β-cells.
The effect of FFAs on insulin secretion by pancreatic β-cells depends on exposure time, concentration, and the type of FFA [271,273]. Acute exposure caused an increase, whereas chronic exposure caused the suppression of insulin secretion by pancreatic β-cells [271]. Interestingly, mainly saturated FFAs (palmitate and stearate) synergize with elevated concentrations of glucose to cause pancreatic β-cell death (lipotoxicity), whereas oleate is practically nontoxic [273]. One possible explanation of the unfavorable effect of saturated FFAs on insulin secretion by pancreatic β-cells could be the negative regulation of Idx-1 by saturated FFAs and the suppression of genes transactivated by IDX-1, including GLUT2, glucokinase, and insulin [274]. The inhibitory effect of FFAs (palmitate) strictly depends on βOX since it was prevented by inhibiting CPT1 [274].
Overall, the results discussed above indicate that mitochondrial βOX occurs in pancreatic β-cells and plays an important role in regulating insulin secretion.
In the pancreatic β-cells, similar to other organs, FAO occurs in mitochondria and peroxisomes [275,276]. However, it is not known to what extent peroxisome FAO contributes to FFA oxidation in pancreatic β-cells. Nevertheless, one has to remember that catalase, which is responsible for potentially toxic H2O2 (formed during peroxisome βOX) degradation, is practically not detectable in pancreatic β-cells, which might contribute to the development of T2D due to increased plasma FFA concentrations [276]. Moreover, it has been shown that the overexpression of catalase in the peroxisomes (but not in mitochondria) of insulin-producing cells (RINm5F cells with low catalase activity and good model cells for the study of H2O2-mediated lipotoxicity) (a) decreased the H2O2 level and (b) protected the cells against FFA-induced toxicity. Based on these data, it was postulated that peroxisomal βOX is involved in lipotoxicity via the synthesis of H2O2 [276].

3. FAO in Cancer

One of the distinctive features of cancer cells is a significant increase in ATP production. In cancer cells, ATP is needed to synthesize many micro- and macromolecules (often called biomass) that are essential for cell division and proliferation [277]. In most cancer cells, an increase in ATP synthesis is associated with an increase in glycolysis and glutaminolysis [278]. However, carcinogenesis is also related to significant lipid metabolism disturbances [279,280,281]. An upregulation of FAO enzymes has been reported in many malignancies [282,283,284,285,286,287,288]. The data presented in Table 4 indicate that gene-encoding FAO enzymes or proteins associated with FAO (e.g., FABPs) are upregulated in many, but not all, human cancers.
On this basis, it is conceivable that under conditions in which cancer cells require an additional amount of ATP, FAO can play an important role in ATP synthesis. Indeed, it has been shown that activated FAO increases ATP levels and promote cell survival in breast cancer cells and other tumor cells [337,338,339,340]. Moreover, it has been reported that CPT1C promotes cell survival and tumor growth under conditions of metabolic stress [313]. On the other hand, the inhibition of CPT1 resulted in a reduced proliferation of many cancer cells [341]. All results mentioned above indicate the important role of FAO in various cancer cells’ survival and growth. A potential role of FAO in cancer cell survival and growth is presented in Figure 5. As shown in Figure 5, FAO can provide not only ATP but also NADPH, an important compound for cancer cells’ growth and survival.
In cancer cells (similar to noncancer), NADPH is required for the generation of new building blocks, mainly FFAs (necessary for membrane phospholipids synthesis) and cholesterol (an important element of cells membranes), to sustain cell growth and proliferation [278,279,342]. Moreover, NADPH is also used to maintain cellular redox potential, mainly to keep a physiological level of reduced glutathione (GSH). GSH is a scavenger of toxic oxidative metabolites in the cancer cells and is involved in the conversion of excess harmful H2O2 to H2O. A disturbance in NADPH production in the cells increases sensitivity to ROS and, consequently, cell death [343]. Overcoming metabolic stress is an important process for tumor cell growth. Indeed, it has been shown that FAO may provide NADPH for defense against oxidative stress and glioblastoma cell death [344]. Similar results have been obtained using lymphoma cells (a subset of diffuse large B cells) and other carcinoma cells [313,339,340,342]. Therefore, increased NADPH production associated with FAO enhances redox buffering capacity and consequently protects cancer cells from ROS-induced damage. Overall, the data discussed above and presented in Figure 5 indicate the relevance of FAO for some cancer cell functions associated with ATP and NADPH production.
Several other data also suggest the contribution of FAO to cancer cell function. For instance, the uptake of FFAs from surrounding adipocytes promoted FAO in breast and colorectal cancers [345,346,347]. Moreover, some studies suggest that increased FAO may promote cancer metastasis by increasing ATP levels, allowing cancer cells to avoid apoptosis and facilitating epithelial-to-mesenchymal transition [341]. Recent studies reported that osteopontin, protein secreted by many cells, including adipocytes, upregulates the expression of CPT1A in prostate cancer tumor cells. The knockdown of CTP1A diminishes prostate cancer cells’ proliferation and invasiveness capacity. Furthermore, patients with the highest osteopontin gene (SPP1) expression had the worst prognostic outcome [348]. Some FAO genes were also altered in glioblastoma multiforme (GBM), the most aggressive brain cancer in adults [349]. The expression of CPT1A, CPT1B, and ACAD9 was elevated in recurrent gliomas compared to primary tumors, whereas there was no difference in the expression of VLCAD and SCAD between primary and recurrent GBM. Moreover, the overexpression of CPT1B, LCAD, and MCAD was associated with lower overall survival of patients with GBM [289]. Various ACSL isoforms are overexpressed in colorectal, breast, prostate, and other cancers [290,350].
FAO may also increase the drug resistance of cancer cells, which was proven for dexamethasone, L-asparaginase, and tamoxifen [351,352,353]. Moreover, FAO may be essential in the chemoresistance and radioresistance of GBM and triple-negative breast cancer [208,289].
Moreover, the LCAD expression level was proposed as a hepatocellular carcinoma (HCC) patient mortality predictor [334,354]. The overexpression of ACSL in tumors of colorectal cancer patients is associated with a poorer prognosis [355]. Overall, one can conclude that FAO could be involved in invasiveness capacity, chemoresistance, and radioresistance, the promotion of cancer metastasis in some cancers, and be a mortality predictor.
The above-presented data suggest that FAO could be a potential therapeutic target, and its inhibition may reduce cancer cell proliferation, metastasis, and drug resistance. Table 5 presents examples of cancer cell FAO as potential therapeutic targets.
Using different cell lines, attempts have been made to inhibit the transformation at the stage catalyzed by ACSL. The inhibition of ACSL in cancer cells is associated with cell growth inhibition (Table 5). As CPT1 is the rate-limiting enzyme of FAO, most studies were looking for potential anticancer drugs focused on this enzyme. In mice with colon adenocarcinoma, the administration of etomoxir, an irreversible pharmacological CPT1 inhibitor, significantly delayed tumor growth and induced apoptosis [365]. It was also shown that inhibiting FAO by etomoxir enhanced the anticancer effect of cisplatin in HCT116 colon cancer cells [372]. Combining etomoxir with radiotherapy improved its effectiveness in an in vitro lung epithelial and prostate cancer cell model [366]. Moreover, some data indicate that CPT1 inhibition may prevent metastasis [288]. However, high concentrations of etomoxir can also inhibit complex I of the mitochondrial respiratory chain and reduce cell proliferation independently of FFA oxidation [373]. It should be noted that a more selective CPT1 inhibitor, teglicar, was developed, which is a reversible CPT1 inhibitor with less toxicity than etomoxir that prevented MYC-driven lymphomagenesis [374]. Perhexiline is an inhibitor of the CPT1 and CPT2 isoforms, and its use sensitizes cancer cells to the anticancer effect of oxaliplatin and increases their apoptosis [370]. Like other CPT inhibitors, perhexiline inhibits FFA oxidation, and enhanced ROS accumulation allows classical chemotherapeutic drugs to kill more CRC cells [370]. The results presented above and summarized in Table 5 indicate that FAO inhibitors have a potential role in cancer therapy. Importantly, some compounds presented in Table 4 (for instance, perhexiline, an inhibitor of CPT1, is approved for human use for the treatment of some diseases [278]). Therefore, these findings may represent an important step toward improving some cancer treatments in the near future.
It has been shown that a ketogenic diet or fasting limits tumor progression by different mechanisms, such as (a) lowering blood glucose and insulin concentrations, altering lipid metabolism, and (c) increasing BHB concentrations [375,376,377]. The recently published result indicates that the inhibition of succinyl-CoA:3-oxoacid-CoA transferase (SCOT), which plays a crucial role in KB oxidation, also reduces tumor volume and inflammation in the Lewis cancer model [378]. The reaction catalyzed by this enzyme is presented below:
acetoacetate + succinyl-CoA → acetoacetyl-CoA + succinate
It suggests that KB oxidation can increase ATP production for the growth of cancer cells. Thus, one can suppose that FAO via an increase in KB synthesis may support cancer growth. The inhibition of SCOT may cause (a) a decrease in ATP synthesis and (b) an increase in BHB (precursor of acetoacetate) concentrations. Both a decrease in ATP synthesis and an increase in BHB may limit tumor progression by a different mechanism (BHB via Hcar2-Hops signaling) [377].
Together, the results presented above suggest that FAO may promote tumor growth, whereas the inhibition of FAO can lead to a reduction in tumor growth.
However, it should be emphasized that the involvement of FAO in cancer cells’ growth and function is still a debated issue because some data suggest that FAO is not necessarily relevant for ATP synthesis in certain cancer cells. The data presented in Table 4 indicate that gene-encoding FAO enzymes are downregulated in some human cancers. For instance, in HCC with a high ACSL expression, most genes encoding enzymes involved in FAO were significantly downregulated [293]. Similarly, in vitro and in vivo studies suggested that the downregulation of MCAD and LCAD enhances tumor proliferation and aggressiveness. Also, ACSL1 is reported to be downregulated in non-small-cell lung cancer [290].

4. The Pathogenic Genetic Make-Up of FAO Genes

The diseases caused by mutations in gene-encoding FAO enzymes are rare or even very rare (for details, see Supplementary Table S1). Pathogenic changes may include sequence or copy-number variants. Some variations in FAO genes are part of more significant genetic disturbances. Associations between specific single-nucleotide polymorphisms (SNPs) in FAO genes and various biological traits or pathological conditions like T2D, cardiovascular disease, and CKD (for details, see Supplementary Table S2) have been reported [379,380,381,382,383,384,385].
MCAD deficiency is the most frequent disorder of FAO [386,387]. More than 500 sequence variations of MCAD have been reported so far; almost half of them are pathogenic or likely pathogenic. However, approximately 80% to 90% of the disease-causing sequence variations in caucasian patients are due to a single-base mutation: c.985A > G [388,389]. Compared to other variants, homozygosity for this mutation is associated with the most severe phenotype, including sudden infant death [386,390]. Moreover, the same single-base mutation in MCAD (c.985A > G) was observed in patients with Reye syndrome and Reye-like syndromes. However, the consequences and importance of these associations are not fully understood [391,392,393].
LCHAD deficiency (LCHADD) is diagnosed when a mutation in the alpha subunit of mitochondrial trifunctional protein (HADHA) causes an isolated deficiency of LCHAD. The most abundant pathogenic mutation is c.1528-G > C. This missense variation causes a loss of enzyme activity without changing the conformation and assembly of the MTP complex [394,395]. Although the worldwide LCHADD prevalence is estimated at 1/250,000 in Baltic Sea areas, the frequency is higher, especially in the Pomeranian district (1/20,000) [396].
Mitochondrial trifunctional protein deficiency (MTPD) is diagnosed when mutations in HADHA or HADHB (a beta subunit of mitochondrial trifunctional protein) genes lead to a deficiency of all enzyme activities in the MTP complex. According to the Orphanet database, MTPD has been reported in less than 100 cases (Orphanet). Although the clinical manifestations of pathogenic variants of HADHA and HADHB are similar, it is more likely that patients with HADHA mutations will have a severe/lethal phenotype [397]. Moreover, the survival rate for MTPD is lower than LCHADD [398,399]. In some cases, HELLP syndrome (hemolysis, elevated liver enzymes, lowered platelets) may occur in pregnant women carrying a fetus with HADHA or HADHB pathogenic mutations [400,401].
Most of the pathogenic variants of CPT1A result in undetectable or extremely low enzymatic activity [402,403]. Although CPT1 deficiency is very rare in the general population, the frequency of the milder phenotype c.1436C > T (p.P479L) is much higher in Inuit, Alaskan Native, and Canadian First Nations (even up to 1.3/1000) [404,405]. Spastic paraplegia 73 is a neurodegenerative disorder characterized by slow, gradual, and progressive weakness, and spasticity of the lower limbs is caused by mutations in CPT1C. Up to 2019, only two families were diagnosed with it. Minimal data suggested that pathogenic mutations destabilize the interaction between the regulatory and catalytic domains of the enzyme [406,407].
CPT2 deficiency has three clinical forms: lethal neonatal, severe infantile, and myopathic (which may manifest from infancy to adulthood). The myopathic form is the most common and the least severe [408,409]. In some individuals, even heterozygous pathogenic mutations may give symptoms of the myopathic form when accompanied by specific triggers (e.g., excessive exercise) [410]. Moreover, some single-base mutations in CPT2 are associated with susceptibility to infection-induced acute encephalopathy 4 [411,412].
A lack of a functional OCTN2 carnitine transporter in cell membranes leads to primary carnitine deficiency, an autosomal recessive disorder of FAO, which has a frequency of 1:40,000–1:100,000 in newborns. The absence of the cell membrane carnitine transporter causes (a) urinary carnitine wasting, (b) a significant decrease in intracellular carnitine concentration, and (c) decreased plasma-free carnitine (0–5 µmol/L in patients with primary carnitine deficiency versus 25–50 µmol/L in healthy patients) and acylated carnitine [67]. Younger children with primary carnitine deficiency display problems with (a) feeding, (b) respiratory infection, and (c) acute gastroenteritis (so-called metabolic syndrome). Later on, patients become lethargic and have hepatomegaly. Laboratory examination usually reveals (a) hypoglycemia with minimal or no KBs in urine and (b) hyperammonemia. Older patients dominate cardiomyopathy. Sometimes, older patients display both metabolic and cardiac symptoms. Moreover, a few patients with primary carnitine deficiency have been completely asymptotic for all of their lives. Primary carnitine deficiency can be successfully treated by carnitine supplementation (usually 100–400 mg per kg body weight per day) if the treatment is started before organ damage occurs. Unfortunately, a high dose of carnitine has side effects, like diarrhea and intestinal discomfort [67].
In SCAD deficiency (SCADD), mild, moderate, and severely decreased enzyme function can be observed despite no correlation between the clinical phenotype and the degree of SCAD dysfunction. The most common variations in SCADD patients, c.511C > T and c.625G > A, are also present in approximately 14% of the general population. The rarity of ACADS inactivating variants and the lack of clinical significance in many patients lead to questions regarding the clinical relevance of SCADD as a hereditary disease [386,413,414,415].
Upon closer examination, all patients diagnosed with LCAD dehydrogenase deficiency before 1992 were shown to have a defect in VLCAD [416,417,418]. More than 90 pathogenic variations in VLCAD were identified, with the c.848T > C pathogenic variant as the most frequent [419]. Sequence variations associated with a complete loss of function result in death in the first few days of life [386].
The prevalence of mitochondrial short-chain enoyl-CoA hydratase 1 deficiency (ECHS1D) remains unknown since it is a sporadic disease with less than 50 cases worldwide (data until 2020) [420,421]. Pathogenic variants of ECHS1 lead to a decrease in enzyme activity. The degree of function loss can vary and determines the severity of clinical symptoms [422,423]. In some patients with Leigh syndrome, a severe neurological disorder was caused by mutations in succinate dehydrogenase complex and/or genes related to the oxidative phosphorylation pathway, and sequence variations in ECHS1 were also observed [424,425,426]. Moreover, ECHS1D has also been described in rare cases of patients with severe neonatal lactic acidosis, cardiomyopathy, cutis laxa, and exercise-induced dystonia [427,428,429,430].
Fanconi renotubular syndrome is a family of related diseases characterized by the dysfunction of proximal tubular epithelial cells, leading to the urinary leak of essential metabolites, and the different syndrome types indicate in which gene the mutation occurred. In Fanconi renotubular syndrome type 3, a single base substitution in enoyl-CoA hydratase and 3-hydroxyacyl CoA dehydrogenase (EHHADH) leads to a missense mutation. Mutated EHHADH can localize mainly in mitochondria rather than peroxisomes and functionally disrupt the MTP complex [431,432]. EHHADH deficiency may also lead to clinical symptoms resembling Zellweger syndrome, a rare peroxisome biogenesis disorder [433,434].
As a consequence of a better understanding of the biochemical traits (especially activity toward substrates with different chain lengths) of mitochondrial types of HAD, many patients initially diagnosed with SCHAD deficiency based on their symptoms were suffering from HAD deficiency (HADD) [386,435]. Pathogenic mutations in the coding sequence, introns, or regulatory regions severely reduce HAD activity, mainly in the liver [436,437,438]. Mutations in HAD are observed in less than 1% of all familial hyperinsulinemia hypoglycemia cases [439,440,441].
Peroxisomal acyl-CoA oxidase deficiency occurs due to the defects in ACOX1. As a consequence of clinical and biochemical features resembling neonatal adrenoleukodystrophy, this disorder is also known as pseudoneonatal adrenoleukodystrophy (pseuso-NALD). Until 2022, only around 30 patients with pseudo-NALD were reported in the literature [442]. Pseudo-NALD causes increased levels of VLCFAs in the tissues and plasma of the patients, while BCFAs remain at normal levels [443].
X-ALD is an X-linked inherited disease associated with severe morbidity and mortality in most affected subjects. It is characterized by impaired peroxisomal βOX of VLCFAs (C22 and more), which is reduced to approx. 30% of healthy subjects [444]. It is a disease with a frequency in 1:17,000 newborns and is caused by mutations in the ABCD1 gene located on the X-chromosome [445,446]. Mutations in the ABCD1 gene (approx. 600 different mutations have been identified so far) cause the absence or dysfunction of this transporter.
Consequently, the accumulation of VLCFAs in plasma and tissues/organs, including the brain’s white matter, the spinal cord, and the adrenal cortex, occurs. Accumulated VLCFAs in tissue/organs are toxic because they disrupt cell membranes’ structure, stability, and function. So far, there is no treatment for most patients with X-ALD [447]. However, studies conducted on Abcd1 knock-out mice and human and mouse X-ALD fibroblasts revealed that overexpression of abcd2 or abcd3 may restore peroxisomal VLCFA β-oxidation [448].

5. Conclusions

The data presented in this review indicate the importance of βOX in an increasing number of tissues and organs, even those previously not considered important. Disturbances in βOX and the α- and ω-oxidation of FAs, including those caused by genetic defects, play an important role in developing various diseases. Several studies also indicate that carcinogenesis is associated with significant disturbances in βOX. Thus, deeper knowledge of the mechanisms linking a disturbance in βOX to several pathologies, including carcinogenesis, is needed to identify novel diagnostic markers and potential therapeutic interventions that may optimize the clinical management of patients with βOX and the α- and ω-oxidation of FA-related disorders.

Supplementary Materials

The following supporting information can be downloaded at https://www.mdpi.com/article/10.3390/ijms241914857/s1, Refs. [449,450,451,452,453,454,455,456,457,458,459,460,461,462,463,464,465,466,467,468,469,470,471,472,473,474,475,476,477,478,479,480,481,482,483,484,485,486,487,488,489,490,491,492,493,494,495,496,497,498,499,500] are cited in Supplementary Materials.

Author Contributions

Conceptualization, T.S. and E.S.; writing—original draft preparation, S.S.-J., A.C., J.T., A.H., T.S., E.S. and J.S.; writing—review and editing, S.S.-J. and A.C.; supervision, J.S.; All authors have read and agreed to the published version of the manuscript.

Funding

This research was funded by Medical University of Gdansk grants no. ST-40 and ST-41.

Institutional Review Board Statement

Not applicable.

Informed Consent Statement

Not applicable.

Data Availability Statement

No new data were created.

Conflicts of Interest

The authors declare no conflict of interest. The funders had no role in the study’s design; in the collection, analyses, or interpretation of data; in the writing of the manuscript; or in the decision to publish the results.

References

  1. He, Q.; Chen, Y.; Wang, Z.; He, H.; Yu, P. Cellular Uptake, Metabolism and Sensing of Long-Chain Fatty Acids. Front. Biosci. Landmark 2023, 28, 10. [Google Scholar] [CrossRef] [PubMed]
  2. Wanders, R.J.A.; Komen, J.; Kemp, S. Fatty acid omega-oxidation as a rescue pathway for fatty acid oxidation disorders in humans. FEBS J. 2011, 278, 182–194. [Google Scholar] [CrossRef] [PubMed]
  3. Wanders, R.J.A.; Komen, J.; Ferdinandusse, S. Phytanic acid metabolism in health and disease. Biochim. Biophys. Acta 2011, 1811, 498–507. [Google Scholar] [CrossRef]
  4. Sanders, R.-J.; Ofman, R.; Valianpour, F.; Kemp, S.; Wanders, R.J.A. Evidence for two enzymatic pathways for omega-oxidation of docosanoic acid in rat liver microsomes. J. Lipid Res. 2005, 46, 1001–1008. [Google Scholar] [CrossRef] [PubMed]
  5. Brandt, J.M.; Djouadi, F.; Kelly, D.P. Fatty acids activate transcription of the muscle carnitine palmitoyltransferase I gene in cardiac myocytes via the peroxisome proliferator-activated receptor alpha. J. Biol. Chem. 1998, 273, 23786–23792. [Google Scholar] [CrossRef]
  6. Desvergne, B.; Wahli, W. Peroxisome proliferator-activated receptors: Nuclear control of metabolism. Endocr. Rev. 1999, 20, 649–688. [Google Scholar] [CrossRef]
  7. Tahri-Joutey, M.; Andreoletti, P.; Surapureddi, S.; Nasser, B.; Cherkaoui-Malki, M.; Latruffe, N. Mechanisms Mediating the Regulation of Peroxisomal Fatty Acid Beta-Oxidation by PPARα. Int. J. Mol. Sci. 2021, 22, 8969. [Google Scholar] [CrossRef]
  8. Maciejewska-Skrendo, A.; Buryta, M.; Czarny, W.; Król, P.; Stastny, P.; Petr, M.; Safranow, K.; Sawczuk, M. The Polymorphisms of the Peroxisome-Proliferator Activated Receptors’ Alfa Gene Modify the Aerobic Training Induced Changes of Cholesterol and Glucose. J. Clin. Med. 2019, 8, 1043. [Google Scholar] [CrossRef]
  9. Forman, B.M.; Chen, J.; Evans, R.M. Hypolipidemic drugs, polyunsaturated fatty acids, and eicosanoids are ligands for peroxisome proliferator-activated receptors alpha and delta. Proc. Natl. Acad. Sci. USA 1997, 94, 4312–4317. [Google Scholar] [CrossRef]
  10. Ellinghaus, P.; Wolfrum, C.; Assmann, G.; Spener, F.; Seedorf, U. Phytanic acid activates the peroxisome proliferator-activated receptor α (PPARα) in sterol carrier protein 2-/sterol carrier protein x-deficient mice. J. Biol. Chem. 1999, 274, 2766–2772. [Google Scholar] [CrossRef]
  11. Duszka, K.; Gregor, A.; Guillou, H.; König, J.; Wahli, W. Peroxisome Proliferator-Activated Receptors and Caloric Restriction-Common Pathways Affecting Metabolism, Health, and Longevity. Cells 2020, 9, 1708. [Google Scholar] [CrossRef] [PubMed]
  12. Mirza, A.Z.; Althagafi, I.I.; Shamshad, H. Role of PPAR receptor in different diseases and their ligands: Physiological importance and clinical implications. Eur. J. Med. Chem. 2019, 166, 502–513. [Google Scholar] [CrossRef]
  13. Muoio, D.M.; MacLean, P.S.; Lang, D.B.; Li, S.; Houmard, J.A.; Way, J.M.; Winegar, D.A.; Corton, J.C.; Dohm, G.L.; Kraus, W.E. Fatty acid homeostasis and induction of lipid regulatory genes in skeletal muscles of peroxisome proliferator-activated receptor (PPAR) alpha knock-out mice. Evidence for compensatory regulation by PPAR delta. J. Biol. Chem. 2002, 277, 26089–26097. [Google Scholar] [CrossRef]
  14. de Lange, P.; Farina, P.; Moreno, M.; Ragni, M.; Lombardi, A.; Silvestri, E.; Burrone, L.; Lanni, A.; Goglia, F. Sequential changes in the signal transduction responses of skeletal muscle following food deprivation. FASEB J. Off. Publ. Fed. Am. Soc. Exp. Biol. 2006, 20, 2579–2581. [Google Scholar] [CrossRef] [PubMed]
  15. Luquet, S.; Lopez-Soriano, J.; Holst, D.; Fredenrich, A.; Melki, J.; Rassoulzadegan, M.; Grimaldi, P.A. Peroxisome proliferator-activated receptor delta controls muscle development and oxidative capability. FASEB J. Off. Publ. Fed. Am. Soc. Exp. Biol. 2003, 17, 2299–2301. [Google Scholar] [CrossRef]
  16. Manickam, R.; Wahli, W. Roles of Peroxisome Proliferator-Activated Receptor β/δ in skeletal muscle physiology. Biochimie 2017, 136, 42–48. [Google Scholar] [CrossRef] [PubMed]
  17. Neels, J.G.; Grimaldi, P.A. Physiological functions of peroxisome proliferator-activated receptor β. Physiol. Rev. 2014, 94, 795–858. [Google Scholar] [CrossRef]
  18. Wang, Y.; Nakajima, T.; Gonzalez, F.J.; Tanaka, N. PPARs as Metabolic Regulators in the Liver: Lessons from Liver-Specific PPAR-Null Mice. Int. J. Mol. Sci. 2020, 21, 2061. [Google Scholar] [CrossRef]
  19. Abdelmagid, S.A.; Clarke, S.E.; Nielsen, D.E.; Badawi, A.; El-Sohemy, A.; Mutch, D.M.; Ma, D.W.L. Comprehensive profiling of plasma fatty acid concentrations in young healthy Canadian adults. PLoS ONE 2015, 10, e0116195. [Google Scholar] [CrossRef]
  20. Janczy, A.; Szymanski, M.; Stankiewicz, M.; Kaska, L.; Waleron, K.; Stelmanska, E.; Sledzinski, T.; Mika, A. Increased Amount of Polyunsaturated Fatty Acids in the Intestinal Contents of Patients with Morbid Obesity. Obes. Surg. 2023, 33, 1228–1236. [Google Scholar] [CrossRef]
  21. Huber, A.H.; Kleinfeld, A.M. Unbound free fatty acid profiles in human plasma and the unexpected absence of unbound palmitoleate. J. Lipid Res. 2017, 58, 578–585. [Google Scholar] [CrossRef]
  22. Rojek, L.; Hebanowska, A.; Stojek, M.; Jagielski, M.; Goyke, E.; Szrok-Jurga, S.; Smoczynski, M.; Swierczynski, J.; Sledzinski, T.; Adrych, K. High levels of reactive oxygen species in pancreatic necrotic fluid of patients with walled-off pancreatic necrosis. Gastroenterol. Rev. Gastroenterol. 2020, 16, 56–61. [Google Scholar] [CrossRef]
  23. Jupin, M.; Michiels, P.J.; Girard, F.C.; Spraul, M.; Wijmenga, S.S. NMR identification of endogenous metabolites interacting with fatted and non-fatted human serum albumin in blood plasma: Fatty acids influence the HSA-metabolite interaction. J. Magn. Reson. 2013, 228, 81–94. [Google Scholar] [CrossRef]
  24. Roden, M.; Stingl, H.; Chandramouli, V.; Schumann, W.C.; Hofer, A.; Landau, B.R.; Nowotny, P.; Waldhäusl, W.; Shulman, G.I. Effects of free fatty acid elevation on postabsorptive endogenous glucose production and gluconeogenesis in humans. Diabetes 2000, 49, 701–707. [Google Scholar] [CrossRef]
  25. Pavićević, I.D.; Jovanović, V.B.; Takić, M.M.; Aćimović, J.M.; Penezić, A.Z.; Mandić, L.M. Quantification of total content of non-esterified fatty acids bound to human serum albumin. J. Pharm. Biomed. Anal. 2016, 129, 43–49. [Google Scholar] [CrossRef] [PubMed]
  26. Schwenk, R.W.; Holloway, G.P.; Luiken, J.J.F.P.; Bonen, A.; Glatz, J.F.C. Fatty acid transport across the cell membrane: Regulation by fatty acid transporters. Prostaglandins Leukot. Essent. Fat. Acids 2010, 82, 149–154. [Google Scholar] [CrossRef]
  27. De Leeuw, A.M.; Brouwer, A.; Knook, D.L. Sinusoidal endothelial cells of the liver: Fine structure and function in relation to age. J. Electron Microsc. Tech. 1990, 14, 218–236. [Google Scholar] [CrossRef] [PubMed]
  28. Arts, T.; Reneman, R.S.; Bassingthwaighte, J.B.; van der Vusse, G.J. Modeling Fatty Acid Transfer from Artery to Cardiomyocyte. PLoS Comput. Biol. 2015, 11, e1004666. [Google Scholar] [CrossRef] [PubMed]
  29. Glatz, J.F.C.; Nabben, M.; Luiken, J.J.F.P. CD36 (SR-B2) as master regulator of cellular fatty acid homeostasis. Curr. Opin. Lipidol. 2022, 33, 103. [Google Scholar] [CrossRef] [PubMed]
  30. Ma, Y.; Nenkov, M.; Chen, Y.; Press, A.T.; Kaemmerer, E.; Gassler, N. Fatty acid metabolism and acyl-CoA synthetases in the liver-gut axis. World J. Hepatol. 2021, 13, 1512. [Google Scholar] [CrossRef]
  31. Heden, T.D.; Franklin, M.P.; Dailey, C.; Mashek, M.T.; Chen, C.; Mashek, D.G. ACOT1 deficiency attenuates high-fat diet induced fat mass gain by increasing energy expenditure. J. Clin. Investig. 2023, 8, e160987. [Google Scholar] [CrossRef]
  32. Angelini, A.; Saha, P.K.; Jain, A.; Jung, S.Y.; Mynatt, R.L.; Pi, X.; Xie, L. PHDs/CPT1B/VDAC1 axis regulates long-chain fatty acid oxidation in cardiomyocytes. Cell Rep. 2021, 37, 109767. [Google Scholar] [CrossRef]
  33. Mashek, D.G.; Bornfeldt, K.E.; Coleman, R.A.; Berger, J.; Bernlohr, D.A.; Black, P.; DiRusso, C.C.; Farber, S.A.; Guo, W.; Hashimoto, N.; et al. Revised nomenclature for the mammalian long-chain acyl-CoA synthetase gene family. J. Lipid Res. 2004, 45, 1958–1961. [Google Scholar] [CrossRef]
  34. Pei, Z.; Fraisl, P.; Berger, J.; Jia, Z.; Forss-Petter, S.; Watkins, P.A. Mouse very long-chain Acyl-CoA synthetase 3/fatty acid transport protein 3 catalyzes fatty acid activation but not fatty acid transport in MA-10 cells. J. Biol. Chem. 2004, 279, 54454–54462. [Google Scholar] [CrossRef]
  35. Gimeno, R.E.; Ortegon, A.M.; Patel, S.; Punreddy, S.; Ge, P.; Sun, Y.; Lodish, H.F.; Stahl, A. Characterization of a heart-specific fatty acid transport protein. J. Biol. Chem. 2003, 278, 16039–16044. [Google Scholar] [CrossRef]
  36. Richards, M.R.; Harp, J.D.; Ory, D.S.; Schaffer, J.E. Fatty acid transport protein 1 and long-chain acyl coenzyme A synthetase 1 interact in adipocytes. J. Lipid Res. 2006, 47, 665–672. [Google Scholar] [CrossRef] [PubMed]
  37. Gimeno, R.E. Fatty acid transport proteins. Curr. Opin. Lipidol. 2007, 18, 271–276. [Google Scholar] [CrossRef] [PubMed]
  38. Doege, H.; Baillie, R.A.; Ortegon, A.M.; Tsang, B.; Wu, Q.; Punreddy, S.; Hirsch, D.; Watson, N.; Gimeno, R.E.; Stahl, A. Targeted Deletion of FATP5 Reveals Multiple Functions in Liver Metabolism: Alterations in Hepatic Lipid Homeostasis. Gastroenterology 2006, 130, 1245–1258. [Google Scholar] [CrossRef] [PubMed]
  39. Lewin, T.M.; Kim, J.H.; Granger, D.A.; Vance, J.E.; Coleman, R.A. Acyl-CoA synthetase isoforms 1, 4, and 5 are present in different subcellular membranes in rat liver and can be inhibited independently. J. Biol. Chem. 2001, 276, 24674–24679. [Google Scholar] [CrossRef]
  40. Poppelreuther, M.; Rudolph, B.; Du, C.; Großmann, R.; Becker, M.; Thiele, C.; Ehehalt, R.; Füllekrug, J. The N-terminal region of acyl-CoA synthetase 3 is essential for both the localization on lipid droplets and the function in fatty acid uptake. J. Lipid Res. 2012, 53, 888–900. [Google Scholar] [CrossRef] [PubMed]
  41. Kuwata, H.; Hara, S. Role of acyl-CoA synthetase ACSL4 in arachidonic acid metabolism. Prostaglandins Other Lipid Mediat. 2019, 144, 106363. [Google Scholar] [CrossRef]
  42. Bu, S.Y.; Mashek, D.G. Hepatic long-chain acyl-CoA synthetase 5 mediates fatty acid channeling between anabolic and catabolic pathways. J. Lipid Res. 2010, 51, 3270–3280. [Google Scholar] [CrossRef]
  43. Marszalek, J.R.; Kitidis, C.; DiRusso, C.C.; Lodish, H.F. Long-chain acyl-CoA synthetase 6 preferentially promotes DHA metabolism. J. Biol. Chem. 2005, 280, 10817–10826. [Google Scholar] [CrossRef]
  44. Vessey, D.A.; Kelley, M.; Warren, R.S. Characterization of the CoA ligases of human liver mitochondria catalyzing the activation of short- and medium-chain fatty acids and xenobiotic carboxylic acids. Biochim. Biophys. Acta Gen. Subj. 1999, 1428, 455–462. [Google Scholar] [CrossRef]
  45. Miyagawa, Y.; Mori, T.; Goto, K.; Kawahara, I.; Fujiwara-Tani, R.; Kishi, S.; Sasaki, T.; Fujii, K.; Ohmori, H.; Kuniyasu, H. Intake of medium-chain fatty acids induces myocardial oxidative stress and atrophy. Lipids Health Dis. 2018, 17, 1–7. [Google Scholar] [CrossRef] [PubMed]
  46. Moffett, J.R.; Puthillathu, N.; Vengilote, R.; Jaworski, D.M.; Namboodiri, A.M. Acetate Revisited: A Key Biomolecule at the Nexus of Metabolism, Epigenetics and Oncogenesis—Part 1: Acetyl-CoA, Acetogenesis and Acyl-CoA Short-Chain Synthetases. Front. Physiol. 2020, 11, 580167. [Google Scholar] [CrossRef] [PubMed]
  47. Yoshimura, Y.; Araki, A.; Maruta, H.; Takahashi, Y.; Yamashita, H. Molecular cloning of rat acss3 and characterization of mammalian propionyl-CoA synthetase in the liver mitochondrial matrix. J. Biochem. 2017, 161, 279–289. [Google Scholar] [CrossRef] [PubMed]
  48. Montgomery, M.K.; Osborne, B.; Brown, S.H.J.; Small, L.; Mitchell, T.W.; Cooney, G.J.; Turner, N. Contrasting metabolic effects of medium-versus long-chain fatty acids in skeletal muscle. J. Lipid Res. 2013, 54, 3322–3333. [Google Scholar] [CrossRef] [PubMed]
  49. Faye, A.; Esnous, C.; Price, N.T.; Onfray, M.A.; Girard, J.; Prip-Buus, C. Rat liver carnitine palmitoyltransferase 1 forms an oligomeric complex within the outer mitochondrial membrane. J. Biol. Chem. 2007, 282, 26908–26916. [Google Scholar] [CrossRef]
  50. Lee, K.; Kerner, J.; Hoppel, C.L. Mitochondrial carnitine palmitoyltransferase 1a (CPT1a) is part of an outer membrane fatty acid transfer complex. J. Biol. Chem. 2011, 286, 25655–25662. [Google Scholar] [CrossRef] [PubMed]
  51. Rufer, A.C.; Thoma, R.; Hennig, M. Structural insight into function and regulation of carnitine palmitoyltransferase. Cell. Mol. Life Sci. 2009, 66, 2489–2501. [Google Scholar] [CrossRef] [PubMed]
  52. Schlaepfer, I.R.; Joshi, M. CPT1A-mediated Fat Oxidation, Mechanisms, and Therapeutic Potential. Endocrinology 2020, 161, bqz046. [Google Scholar] [CrossRef] [PubMed]
  53. Wolfgang, M.J.; Kurama, T.; Dai, Y.; Suwa, A.; Asaumi, M.; Matsumoto, S.I.; Cha, S.H.; Shimokawa, T.; Lane, M.D. The brain-specific carnitine palmitoyltransferase-1c regulates energy homeostasis. Proc. Natl. Acad. Sci. USA 2006, 103, 7282–7287. [Google Scholar] [CrossRef] [PubMed]
  54. Carrasco, P.; Sahún, I.; McDonald, J.; Ramírez, S.; Jacas, J.; Gratacós, E.; Sierra, A.Y.; Serra, D.; Herrero, L.; Acker-Palmer, A.; et al. Ceramide levels regulated by carnitine palmitoyltransferase 1C control dendritic spine maturation and cognition. J. Biol. Chem. 2012, 287, 21224–21232. [Google Scholar] [CrossRef] [PubMed]
  55. Taïb, B.; Bouyakdan, K.; Hryhorczuk, C.; Rodaros, D.; Fulton, S.; Alquier, T. Glucose regulates hypothalamic long-chain fatty acid metabolism via AMP-activated kinase (AMPK) in neurons and astrocytes. J. Biol. Chem. 2013, 288, 37216–37229. [Google Scholar] [CrossRef] [PubMed]
  56. Van Weeghel, M.; Abdurrachim, D.; Nederlof, R.; Argmann, C.A.; Houtkooper, R.H.; Hagen, J.; Nabben, M.; Denis, S.; Ciapaite, J.; Kolwicz, S.C.; et al. Increased cardiac fatty acid oxidation in a mouse model with decreased malonyl-CoA sensitivity of CPT1B. Cardiovasc. Res. 2018, 114, 1324–1334. [Google Scholar] [CrossRef] [PubMed]
  57. Louet, J.-F.F.; Le May, C.; Pégorier, J.-P.P.; Decaux, J.-F.F.; Girard, J. Regulation of liver carnitine palmitoyltransferase I gene expression by hormones and fatty acids. Biochem. Soc. Trans. 2001, 29, 310–316. [Google Scholar] [CrossRef]
  58. Bruce, C.R.; Hoy, A.J.; Turner, N.; Watt, M.J.; Allen, T.L.; Carpenter, K.; Cooney, G.J.; Febbraio, M.A.; Kraegen, E.W. Overexpression of carnitine palmitoyltransferase-1 in skeletal muscle is sufficient to enhance fatty acid oxidation and improve high-fat diet-induced insulin resistance. Diabetes 2009, 58, 550–558. [Google Scholar] [CrossRef]
  59. Park, E.A.; Mynatt, R.L.; Cook, G.A.; Kashfi, K. Insulin regulates enzyme activity, malonyl-CoA sensitivity and mRNA abundance of hepatic carnitine palmitoyltransferase-I. Biochem. J. 1995, 310, 853–858. [Google Scholar] [CrossRef]
  60. Faye, A.; Borthwick, K.; Esnous, C.; Price, N.T.; Gobin, S.; Jackson, V.N.; Zammit, V.A.; Girard, J.; Prip-Buus, C. Demonstration of N- and C-terminal domain intramolecular interactions in rat liver carnitine palmitoyltransferase 1 that determine its degree of malonyl-CoA sensitivity. Biochem. J. 2005, 387, 67. [Google Scholar] [CrossRef]
  61. Akkaoui, M.; Cohen, I.; Esnous, C.; Lenoir, V.; Sournac, M.; Girard, J.; Prip-Buus, C. Modulation of the hepatic malonyl-CoA-carnitine palmitoyltransferase 1A partnership creates a metabolic switch allowing oxidation of de novo fatty acids. Biochem. J. 2009, 420, 429–438. [Google Scholar] [CrossRef] [PubMed]
  62. Zhu, H.; Shi, J.; De Vries, Y.; Arvidson, D.N.; Cregg, J.M.; Woldegiorgis, G. Functional Studies of Yeast-Expressed Human Heart Muscle Carnitine Palmitoyltransferase I. Arch. Biochem. Biophys. 1997, 347, 53–61. [Google Scholar] [CrossRef] [PubMed]
  63. Roepstorff, C.; Halberg, N.; Hillig, T.; Saha, A.K.; Ruderman, N.B.; Wojtaszewski, J.F.P.; Richter, E.A.; Kiens, B. Malonyl-CoA and carnitine in regulation of fat oxidation in human skeletal muscle during exercise. Am. J. Physiol. Endocrinol. Metab. 2005, 288, 133–142. [Google Scholar] [CrossRef] [PubMed]
  64. Lefort, N.; Glancy, B.; Bowen, B.; Willis, W.T.; Bailowitz, Z.; De Filippis, E.A.; Brophy, C.; Meyer, C.; Højlund, K.; Yi, Z.; et al. Increased Reactive Oxygen Species Production and Lower Abundance of Complex I Subunits and Carnitine Palmitoyltransferase 1B Protein Despite Normal Mitochondrial Respiration in Insulin-Resistant Human Skeletal Muscle. Diabetes 2010, 59, 2444–2452. [Google Scholar] [CrossRef]
  65. Maples, J.M.; Brault, J.J.; Witczak, C.A.; Park, S.; Hubal, M.J.; Weber, T.M.; Houmard, J.A.; Shewchuk, B.M. Differential epigenetic and transcriptional response of the skeletal muscle carnitine palmitoyltransferase 1B (CPT1B) gene to lipid exposure with obesity. Am. J. Physiol. Endocrinol. Metab. 2015, 309, E345. [Google Scholar] [CrossRef]
  66. Song, S.; Attia, R.R.; Connaughton, S.; Niesen, M.I.; Ness, G.C.; Elam, M.B.; Hori, R.T.; Cook, G.A.; Park, E.A. Peroxisome proliferator activated receptor alpha (PPARalpha) and PPAR gamma coactivator (PGC-1alpha) induce carnitine palmitoyltransferase IA (CPT-1A) via independent gene elements. Mol. Cell. Endocrinol. 2010, 325, 54–63. [Google Scholar] [CrossRef]
  67. Longo, N.; Amat Di San Filippo, C.; Pasquali, M. Disorders of carnitine transport and the carnitine cycle. Am. J. Med. Genet. C Semin. Med. Genet. 2006, 142C, 77–85. [Google Scholar] [CrossRef]
  68. Palmieri, F.; Scarcia, P.; Monné, M. Diseases caused by mutations in mitochondrial carrier genes SLC25: A review. Biomolecules 2020, 10, 655. [Google Scholar] [CrossRef]
  69. Pochini, L.; Galluccio, M.; Scumaci, D.; Giangregorio, N.; Tonazzi, A.; Palmieri, F.; Indiveri, C. Interaction of β-lactam antibiotics with the mitochondrial carnitine/acylcarnitine transporter. Chem. Biol. Interact. 2008, 173, 187–194. [Google Scholar] [CrossRef]
  70. Doulias, P.T.; Tenopoulou, M.; Greene, J.L.; Raju, K.; Ischiropoulos, H. Nitric oxide regulates mitochondrial fatty acid metabolism through reversible protein S-nitrosylation. Sci. Signal. 2013, 6, rs1. [Google Scholar] [CrossRef]
  71. Tonazzi, A.; Eberini, I.; Indiveri, C. Molecular mechanism of inhibition of the mitochondrial carnitine/acylcarnitine transporter by omeprazole revealed by proteoliposome assay, mutagenesis and bioinformatics. PLoS ONE 2013, 8, e82286. [Google Scholar] [CrossRef]
  72. Branco, V.; Godinho-Santos, A.; Gonçalves, J.; Lu, J.; Holmgren, A.; Carvalho, C. Mitochondrial thioredoxin reductase inhibition, selenium status, and Nrf-2 activation are determinant factors modulating the toxicity of mercury compounds. Free Radic. Biol. Med. 2014, 73, 95–105. [Google Scholar] [CrossRef]
  73. Soni, M.S.; Rabaglia, M.E.; Bhatnagar, S.; Shang, J.; Ilkayeva, O.; Mynatt, R.; Zhou, Y.P.; Schadt, E.E.; Thornberry, N.A.; Muoio, D.M.; et al. Downregulation of carnitine acyl-carnitine translocase by miRNAs 132 and 212 amplifies glucose-stimulated insulin secretion. Diabetes 2014, 63, 3805–3814. [Google Scholar] [CrossRef]
  74. Tonazzi, A.; Giangregorio, N.; Console, L.; Scalise, M.; La Russa, D.; Notaristefano, C.; Brunelli, E.; Barca, D.; Indiveri, C. Mitochondrial Carnitine/Acylcarnitine Transporter, a Novel Target of Mercury Toxicity. Chem. Res. Toxicol. 2015, 28, 1015–1022. [Google Scholar] [CrossRef]
  75. Giangregorio, N.; Tonazzi, A.; Console, L.; Lorusso, I.; De Palma, A.; Indiveri, C. The mitochondrial carnitine/acylcarnitine carrier is regulated by hydrogen sulfide via interaction with C136 and C155. Biochim. Biophys. Acta 2016, 1860, 20–27. [Google Scholar] [CrossRef]
  76. Giangregorio, N.; Tonazzi, A.; Console, L.; Indiveri, C. Post-translational modification by acetylation regulates the mitochondrial carnitine/acylcarnitine transport protein. Mol. Cell. Biochem. 2017, 426, 65–73. [Google Scholar] [CrossRef]
  77. Huizing, M.; Ruitenbeek, W.; Van den Heuvel, L.P.; Dolce, V.; Iacobazzi, V.; Smeitink, J.A.M.; Palmieri, F.; Frans Trijbels, J.M. Human mitochondrial transmembrane metabolite carriers: Tissue distribution and its implication for mitochondrial disorders. J. Bioenerg. Biomembr. 1998, 30, 277–284. [Google Scholar] [CrossRef]
  78. Iacobazzi, V.; Convertini, P.; Infantino, V.; Scarcia, P.; Todisco, S.; Palmieri, F. Statins, fibrates and retinoic acid upregulate mitochondrial acylcarnitine carrier gene expression. Biochem. Biophys. Res. Commun. 2009, 388, 643–647. [Google Scholar] [CrossRef]
  79. Iacobazzi, V.; Infantino, V.; Palmieri, F. Transcriptional regulation of the mitochondrial citrate and carnitine/acylcarnitine transporters: Two genes involved in fatty acid biosynthesis and β-oxidation. Biology 2013, 2, 284–303. [Google Scholar] [CrossRef]
  80. Lara, C.; Nicola, G.; Saverio, C.; Isabella, B.; Marino, P.; Cesare, I.; Giovanna, I.; Sabrina, C.; Annamaria, T. Human mitochondrial carnitine acylcarnitine carrier: Molecular target of dietary bioactive polyphenols from sweet cherry (Prunus avium L.). Chem. Biol. Interact. 2019, 307, 179–185. [Google Scholar] [CrossRef]
  81. Houten, S.M.; Violante, S.; Ventura, F.V.; Wanders, R.J.A. The Biochemistry and Physiology of Mitochondrial Fatty Acid β-Oxidation and Its Genetic Disorders. Annu. Rev. Physiol. 2016, 78, 23–44. [Google Scholar] [CrossRef]
  82. Adeva-Andany, M.M.; Carneiro-Freire, N.; Seco-Filgueira, M.; Fernández-Fernández, C.; Mouriño-Bayolo, D. Mitochondrial β-oxidation of saturated fatty acids in humans. Mitochondrion 2019, 46, 73–90. [Google Scholar] [CrossRef]
  83. Czumaj, A.; Szrok-Jurga, S.; Hebanowska, A.; Turyn, J.; Swierczynski, J.; Sledzinski, T.; Stelmanska, E. The pathophysiological role of CoA. Int. J. Mol. Sci. 2020, 21, 9057. [Google Scholar] [CrossRef]
  84. Aoyama, T.; Souri, M.; Ushikubo, S.; Kamijo, T.; Yamaguchi, S.; Kelley, R.I.; Rhead, W.J.; Uetake, K.; Tanaka, K.; Hashimoto, T. Purification of human very-long-chain acyl-coenzyme A dehydrogenase and characterization of its deficiency in seven patients. J. Clin. Investig. 1995, 95, 2465–2473. [Google Scholar] [CrossRef]
  85. Sinsheimer, A.; Mohsen, A.W.; Bloom, K.; Karunanidhi, A.; Bharathi, S.; Wu, Y.L.; Schiff, M.; Wang, Y.; Goetzman, E.S.; Ghaloul-Gonzalez, L.; et al. Development and Characterization of a Mouse Model for Acad9 deficiency. Mol. Genet. Metab. 2021, 134, 156. [Google Scholar] [CrossRef]
  86. Goetzman, E.S.; Alcorn, J.F.; Bharathi, S.S.; Uppala, R.; McHugh, K.J.; Kosmider, B.; Chen, R.; Zuo, Y.Y.; Beck, M.E.; McKinney, R.W.; et al. Long-chain Acyl-CoA dehydrogenase deficiency as a cause of pulmonary surfactant dysfunction. J. Biol. Chem. 2014, 289, 10668–10679. [Google Scholar] [CrossRef]
  87. Horowitz, J.F.; Klein, S. Lipid metabolism during endurance exercise. Am. J. Clin. Nutr. 2000, 72, 558S–563S. [Google Scholar] [CrossRef]
  88. Nochi, Z.; Olsen, R.K.J.; Gregersen, N. Short-chain acyl-CoA dehydrogenase deficiency: From gene to cell pathology and possible disease mechanisms. J. Inherit. Metab. Dis. 2017, 40, 641–655. [Google Scholar] [CrossRef]
  89. Xia, C.; Lou, B.; Fu, Z.; Mohsen, A.W.; Shen, A.L.; Vockley, J.; Kim, J.J.P. Molecular mechanism of interactions between ACAD9 and binding partners in mitochondrial respiratory complex I assembly. iScience 2021, 24, 103153. [Google Scholar] [CrossRef]
  90. Beck, M.E.; Zhang, Y.; Bharathi, S.S.; Kosmider, B.; Bahmed, K.; Dahmer, M.K.; Nogee, L.M.; Goetzman, E.S. The common K333Q polymorphism in long-chain acyl-CoA dehydrogenase (LCAD) reduces enzyme stability and function. Mol. Genet. Metab. 2020, 131, 83–89. [Google Scholar] [CrossRef]
  91. Henriques, B.J.; Katrine Jentoft Olsen, R.; Gomes, C.M.; Bross, P. Electron transfer flavoprotein and its role in mitochondrial energy metabolism in health and disease. Gene 2021, 776, 145407. [Google Scholar] [CrossRef]
  92. Salerno, K.M.; Domenico, J.; Le, N.Q.; Stiles, C.D.; Solov’Yov, I.A.; Martino, C.F. Long-Time Oxygen Localization in Electron Transfer Flavoprotein. J. Chem. Inf. Model. 2022, 62, 4191–4199. [Google Scholar] [CrossRef]
  93. Fould, B.; Garlatti, V.; Neumann, E.; Fenel, D.; Gaboriaud, C.; Arlaud, G.J. Structural and functional characterization of the recombinant human mitochondrial trifunctional protein. Biochemistry 2010, 49, 8608–8617. [Google Scholar] [CrossRef] [PubMed]
  94. Xia, C.; Fu, Z.; Battaile, K.P.; Kim, J.J.P. Crystal structure of human mitochondrial trifunctional protein, a fatty acid β-oxidation metabolon. Proc. Natl. Acad. Sci. USA 2019, 116, 6069–6074. [Google Scholar] [CrossRef] [PubMed]
  95. Dagher, R.; Massie, R.; Gentil, B.J. MTP deficiency caused by HADHB mutations: Pathophysiology and clinical manifestations. Mol. Genet. Metab. 2021, 133, 1–7. [Google Scholar] [CrossRef]
  96. Zhang, D.; Yu, W.; Geisbrecht, B.V.; Gould, S.J.; Sprecher, H.; Schulz, H. Functional characterization of Delta3,Delta2-enoyl-CoA isomerases from rat liver. J. Biol. Chem. 2002, 277, 9127–9132. [Google Scholar] [CrossRef] [PubMed]
  97. Van Weeghel, M.; Te Brinke, H.; Van Lenthe, H.; Kulik, W.; Minkler, P.E.; Stoll, M.S.K.; Sass, J.O.; Janssen, U.; Stoffel, W.; Schwab, K.O.; et al. Functional redundancy of mitochondrial enoyl-CoA isomerases in the oxidation of unsaturated fatty acids. FASEB J. 2012, 26, 4316–4326. [Google Scholar] [CrossRef]
  98. Onwukwe, G.U.; Kursula, P.; Koski, M.K.; Schmitz, W.; Wierenga, R.K. Human Δ32-enoyl-CoA isomerase, type 2: A structural enzymology study on the catalytic role of its ACBP domain and helix-10. FEBS J. 2015, 282, 746–768. [Google Scholar] [CrossRef]
  99. Horowitz, J.F.; Leone, T.C.; Feng, W.; Kelly, D.P.; Klein, S. Effect of endurance training on lipid metabolism in women: A potential role for PPARalpha in the metabolic response to training. Am. J. Physiol. Endocrinol. Metab. 2000, 279, E348–E355. [Google Scholar] [CrossRef]
  100. Toogood, H.S.; Van Thiel, A.; Basran, J.; Sutcliffe, M.J.; Scrutton, N.S.; Leys, D. Extensive domain motion and electron transfer in the human electron transferring flavoprotein.medium chain Acyl-CoA dehydrogenase complex. J. Biol. Chem. 2004, 279, 32904–32912. [Google Scholar] [CrossRef]
  101. Jones, P.M.; Butt, Y.; Messmer, B.; Boriak, R.; Bennett, M.J. Medium-chain fatty acids undergo elongation before beta-oxidation in fibroblasts. Biochem. Biophys. Res. Commun. 2006, 346, 193–197. [Google Scholar] [CrossRef]
  102. Houten, S.M.; Wanders, R.J.A.A. A general introduction to the biochemistry of mitochondrial fatty acid β-oxidation. J. Inherit. Metab. Dis. 2010, 33, 469–477. [Google Scholar] [CrossRef]
  103. Vanhove, G.; Veldhoven, P.P.V.; Eyssen, H.J.; Mannaerts, G.P. Mitochondrial short-chain acyl-CoA dehydrogenase of human liver and kidney can function as an oxidase. Biochem. J. 1993, 292 Pt 1, 23–30. [Google Scholar] [CrossRef]
  104. Corydon, T.J.; Bross, P.; Jensen, T.G.; Corydon, M.J.; Lund, T.B.; Jensen, U.B.; Kim, J.J.P.; Gregersen, N.; Bolund, L. Rapid degradation of short-chain acyl-CoA dehydrogenase variants with temperature-sensitive folding defects occurs after import into mitochondria. J. Biol. Chem. 1998, 273, 13065–13071. [Google Scholar] [CrossRef]
  105. Kanazawa, M.; Ohtake, A.; Abe, H.; Yamamoto, S.; Satoh, Y.; Takayanagi, M.; Niimi, H.; Mori, M.; Hashimoto, T. Molecular cloning and sequence analysis of the cDNA for human mitochondrial short-chain enoyl-CoA hydratase. Enzyme Protein 1993, 47, 9–13. [Google Scholar] [CrossRef]
  106. Nakagawa, J.; Waldner, H.; Meyer-Monard, S.; Hofsteenge, J.; Jenö, P.; Moroni, C. AUH, a gene encoding an AU-specific RNA binding protein with intrinsic enoyl-CoA hydratase activity. Proc. Natl. Acad. Sci. USA 1995, 92, 2051–2055. [Google Scholar] [CrossRef] [PubMed]
  107. Vredendaal, P.J.C.M.; Van Den Berg, I.E.T.; Malingré, H.E.M.; Stroobants, A.K.; OldeWeghuis, D.E.M.; Berger, R. Human short-chain L-3-hydroxyacyl-CoA dehydrogenase: Cloning and characterization of the coding sequence. Biochem. Biophys. Res. Commun. 1996, 223, 718–723. [Google Scholar] [CrossRef] [PubMed]
  108. Mannaerts, G.P.; Debeer, L.J.; Thomas, J.; De Schepper, P.J. Mitochondrial and peroxisomal fatty acid oxidation in liver homogenates and isolated hepatocytes from control and clofibrate-treated rats. J. Biol. Chem. 1979, 254, 4585–4595. [Google Scholar] [CrossRef] [PubMed]
  109. Lazarow, P.B.; De Duve, C. A fatty acyl-CoA oxidizing system in rat liver peroxisomes; enhancement by clofibrate, a hypolipidemic drug. Proc. Natl. Acad. Sci. USA 1976, 73, 2043–2046. [Google Scholar] [CrossRef] [PubMed]
  110. Kleiboeker, B.; Lodhi, I.J. Peroxisomal regulation of energy homeostasis: Effect on obesity and related metabolic disorders. Mol. Metab. 2022, 65, 101577. [Google Scholar] [CrossRef] [PubMed]
  111. Vilarinho, S.; Sari, S.; Mazzacuva, F.; Bilgüvar, K.; Esendagli-Yilmaz, G.; Jain, D.; Akyol, G.; Dalgiç, B.; Günel, M.; Clayton, P.T.; et al. ACOX2 deficiency: A disorder of bile acid synthesis with transaminase elevation, liver fibrosis, ataxia, and cognitive impairment. Proc. Natl. Acad. Sci. USA 2016, 113, 11289–11293. [Google Scholar] [CrossRef]
  112. Ferdinandusse, S.; Denis, S.; van Roermund, C.W.T.; Preece, M.A.; Koster, J.; Ebberink, M.S.; Waterham, H.R.; Wanders, R.J.A. A novel case of ACOX2 deficiency leads to recognition of a third human peroxisomal acyl-CoA oxidase. Biochim. Biophys. Acta Mol. Basis Dis. 2018, 1864, 952–958. [Google Scholar] [CrossRef]
  113. Wanders, R.J.A.; Baes, M.; Ribeiro, D.; Ferdinandusse, S.; Waterham, H.R. The physiological functions of human peroxisomes. Physiol. Rev. 2023, 103, 957–1024. [Google Scholar] [CrossRef] [PubMed]
  114. Westin, M.A.K.; Hunt, M.C.; Alexson, S.E.H. Short- and medium-chain carnitine acyltransferases and acyl-CoA thioesterases in mouse provide complementary systems for transport of beta-oxidation products out of peroxisomes. Cell. Mol. Life Sci. 2008, 65, 982–990. [Google Scholar] [CrossRef]
  115. Tawbeh, A.; Gondcaille, C.; Trompier, D.; Savary, S. Peroxisomal ABC Transporters: An Update. Int. J. Mol. Sci. 2021, 22, 6093. [Google Scholar] [CrossRef]
  116. Wang, M.; Wang, K.; Liao, X.; Hu, H.; Chen, L.; Meng, L.; Gao, W.; Li, Q. Carnitine Palmitoyltransferase System: A New Target for Anti-Inflammatory and Anticancer Therapy? Front. Pharmacol. 2021, 12, 76058. [Google Scholar] [CrossRef] [PubMed]
  117. Kawaguchi, K.; Morita, M. ABC Transporter Subfamily D: Distinct Differences in Behavior between ABCD1-3 and ABCD4 in Subcellular Localization, Function, and Human Disease. Biomed Res. Int. 2016, 2016, 1–11. [Google Scholar] [CrossRef]
  118. Wang, Y.; Palmfeldt, J.; Gregersen, N.; Makhov, A.M.; Conway, J.F.; Wang, M.; McCalley, S.P.; Basu, S.; Alharbi, H.S.; Croix, C. Mitochondrial fatty acid oxidation and the electron transport chain comprise a multifunctional mitochondrial protein complex. J. Biol. Chem. 2019, 294, 12380–12391. [Google Scholar] [CrossRef] [PubMed]
  119. Roca-Saavedra, P.; Mariño-Lorenzo, P.; Miranda, J.M.; Porto-Arias, J.J.; Lamas, A.; Vazquez, B.I.; Franco, C.M.; Cepeda, A. Phytanic acid consumption and human health, risks, benefits and future trends: A review. Food Chem. 2017, 221, 237–247. [Google Scholar] [CrossRef]
  120. Steinberg, D.; Vroom, F.Q.; Engel, W.K.; Cammermeyer, J.; Mize, C.E.; Avigan, J. Refsum’s disease--a recently characterized lipidosis involving the nervous system. Combined clinical staff conference at the National Institutes of Health. Ann. Intern. Med. 1967, 66, 365–395. [Google Scholar] [CrossRef]
  121. Durrett, T.P.; Welti, R. The tail of chlorophyll: Fates for phytol. J. Biol. Chem. 2021, 296, 100802. [Google Scholar] [CrossRef] [PubMed]
  122. Wills, A.J.; Manning, N.J.; Reilly, M.M. Refsum’s disease. QJM 2001, 94, 403–406. [Google Scholar] [CrossRef] [PubMed]
  123. Krauß, S.; Vetter, W. Phytol and Phytyl Fatty Acid Esters: Occurrence, Concentrations, and Relevance. Eur. J. Lipid Sci. Technol. 2018, 120, 1700387. [Google Scholar] [CrossRef]
  124. Wanders, R.J.A.; Vreken, P.; Ferdinandusse, S.; Jansen, G.A.; Waterham, H.R.; van Roermund, C.W.T.; Van Grunsven, E.G. Peroxisomal fatty acid alpha- and beta-oxidation in humans: Enzymology, peroxisomal metabolite transporters and peroxisomal diseases. Biochem. Soc. Trans. 2001, 29, 250. [Google Scholar] [CrossRef]
  125. Wanders, R.J.A.; Komen, J.C. Peroxisomes, Refsum’s disease and the alpha- and omega-oxidation of phytanic acid. Biochem. Soc. Trans. 2007, 35, 865–869. [Google Scholar] [CrossRef]
  126. Chen, M.H.; Raffield, L.M.; Mousas, A.; Sakaue, S.; Huffman, J.E.; Moscati, A.; Trivedi, B.; Jiang, T.; Akbari, P.; Vuckovic, D.; et al. Trans-ethnic and Ancestry-Specific Blood-Cell Genetics in 746,667 Individuals from 5 Global Populations. Cell 2020, 182, 1198–1213. [Google Scholar] [CrossRef]
  127. Goldfischer, S.; Johnson, A.B.; Essner, E.; Moore, C.; Ritch, R.H. Peroxisomal abnormalities in metabolic diseases. J. Histochem. Cytochem. 1973, 21, 972–977. [Google Scholar] [CrossRef]
  128. Monnens, L.; Bakkeren, J.; Parmentier, G.; Janssen, G.; van Haelst, U.; Trijbels, F.; Eyssen, H. Disturbances in bile acid metabolism of infants with the Zellweger (cerebro-hepato-renal) syndrome. Eur. J. Pediatr. 1980, 133, 31–35. [Google Scholar] [CrossRef]
  129. Cheillan, D. Zellweger Syndrome Disorders: From Severe Neonatal Disease to Atypical Adult Presentation. Adv. Exp. Med. Biol. 2020, 1299, 71–80. [Google Scholar] [CrossRef]
  130. Alam, A.; Locher, K.P. Structure and Mechanism of Human ABC Transporters. Annu. Rev. Biophys. 2023, 52, 275–300. [Google Scholar] [CrossRef]
  131. Chen, Z.-P.; Xu, D.; Wang, L.; Mao, Y.-X.; Li, Y.; Cheng, M.-T.; Zhou, C.-Z.; Hou, W.-T.; Chen, Y. Structural basis of substrate recognition and translocation by human very long-chain fatty acid transporter ABCD1. Nat. Commun. 2022, 13, 3299. [Google Scholar] [CrossRef]
  132. van Roermund, C.W.T.; IJlst, L.; Wagemans, T.; Wanders, R.J.A.; Waterham, H.R. A role for the human peroxisomal half-transporter ABCD3 in the oxidation of dicarboxylic acids. Biochim. Biophys. Acta Mol. Cell Biol. Lipids 2014, 1841, 563–568. [Google Scholar] [CrossRef]
  133. Kersten, S. Integrated physiology and systems biology of PPARα. Mol. Metab. 2014, 3, 354–371. [Google Scholar] [CrossRef]
  134. Fourcade, S.; Savary, S.; Albet, S.; Gauthé, D.; Gondcaille, C.; Pineau, T.; Bellenger, J.; Bentejac, M.; Holzinger, A.; Berger, J.; et al. Fibrate induction of the adrenoleukodystrophy-related gene (ABCD2): Promoter analysis and role of the peroxisome proliferator-activated receptor PPARα. Eur. J. Biochem. 2001, 268, 3490–3500. [Google Scholar] [CrossRef]
  135. Leclercq, S.; Skrzypski, J.; Courvoisier, A.; Gondcaille, C.; Bonnetain, F.; André, A.; Chardigny, J.-M.; Bellenger, S.; Bellenger, J.; Narce, M.; et al. Effect of dietary polyunsaturated fatty acids on the expression of peroxisomal ABC transporters. Biochimie 2008, 90, 1602–1607. [Google Scholar] [CrossRef]
  136. Hayashi, H.; Takahata, S. Role of peroxisomal fatty acyl-CoA beta-oxidation in phospholipid biosynthesis. Arch. Biochem. Biophys. 1991, 284, 326–331. [Google Scholar] [CrossRef]
  137. Hayashi, H.; Oohashi, M. Incorporation of acetyl-CoA generated from peroxisomal beta-oxidation into ethanolamine plasmalogen of rat liver. Biochim. Biophys. Acta 1995, 1254, 319–325. [Google Scholar] [CrossRef]
  138. Zhang, X.; Wang, Y.; Yao, H.; Deng, S.; Gao, T.; Shang, L.; Chen, X.; Cui, X.; Zeng, J. Peroxisomal β-oxidation stimulates cholesterol biosynthesis in the liver in diabetic mice. J. Biol. Chem. 2022, 298, 101572. [Google Scholar] [CrossRef]
  139. Mariño, G.; Pietrocola, F.; Eisenberg, T.; Kong, Y.; Malik, S.A.; Andryushkova, A.; Schroeder, S.; Pendl, T.; Harger, A.; Niso-Santano, M.; et al. Regulation of Autophagy by Cytosolic Acetyl-Coenzyme A. Mol. Cell 2014, 53, 710–725. [Google Scholar] [CrossRef]
  140. Schulze, R.J.; Sathyanarayan, A.; Mashek, D.G. Breaking fat: The regulation and mechanisms of lipophagy. Biochim. Biophys. Acta Mol. Cell Biol. Lipids 2017, 1862, 1178–1187. [Google Scholar] [CrossRef]
  141. He, A.; Chen, X.; Tan, M.; Chen, Y.; Lu, D.; Zhang, X.; Dean, J.M.; Razani, B.; Lodhi, I.J. Acetyl-CoA Derived from Hepatic Peroxisomal β-Oxidation Inhibits Autophagy and Promotes Steatosis via mTORC1 Activation. Mol. Cell 2020, 79, 30. [Google Scholar] [CrossRef]
  142. Chen, X.; Shang, L.; Deng, S.; Li, P.; Chen, K.; Gao, T.; Zhang, X.; Chen, Z.; Zeng, J. Peroxisomal oxidation of erucic acid suppresses mitochondrial fatty acid oxidation by stimulating malonyl-CoA formation in the rat liver. J. Biol. Chem. 2020, 295, 10168–10179. [Google Scholar] [CrossRef]
  143. Fransen, M.; Lismont, C. Redox Signaling from and to Peroxisomes: Progress, Challenges, and Prospects. Antioxid. Redox Signal. 2019, 30, 95–112. [Google Scholar] [CrossRef]
  144. Terlecky, S.R.; Koepke, J.I.; Walton, P.A. Peroxisomes and aging. Biochim. Biophys. Acta 2006, 1763, 1749–1754. [Google Scholar] [CrossRef]
  145. Lismont, C.; Nordgren, M.; Van Veldhoven, P.P.; Fransen, M. Redox interplay between mitochondria and peroxisomes. Front. Cell Dev. Biol. 2015, 3, 35. [Google Scholar] [CrossRef]
  146. Vallejo, M.J.; Salazar, L.; Grijalva, M. Oxidative stress modulation and ROS-mediated toxicity in cancer: A review on in vitro models for plant-derived compounds. Oxid. Med. Cell. Longev. 2017, 2017, 1–9. [Google Scholar] [CrossRef]
  147. Mahaseth, T.; Kuzminov, A. Potentiation of hydrogen peroxide toxicity: From catalase inhibition to stable DNA-iron complexes. Mutat. Res. Rev. Mutat. Res. 2017, 773, 274–281. [Google Scholar] [CrossRef]
  148. Feng, S.; Sun, Z.; Jia, X.; Li, L.; Wu, Y.; Wu, C.; Lin, L.; Liu, J.; Zeng, B. Lipophagy: Molecular Mechanisms and Implications in Hepatic Lipid Metabolism. Front. Biosci. 2023, 28, 6. [Google Scholar] [CrossRef]
  149. Sonoda, T.; Tatibana, M. Purification of N-acetyl-L-glutamate synthetase from rat liver mitochondria and substrate and activator specificity of the enzyme. J. Biol. Chem. 1983, 258, 9839–9844. [Google Scholar] [CrossRef]
  150. Choudhary, C.; Weinert, B.T.; Nishida, Y.; Verdin, E.; Mann, M. The growing landscape of lysine acetylation links metabolism and cell signalling. Nat. Rev. Mol. Cell Biol. 2014, 15, 536–550. [Google Scholar] [CrossRef]
  151. McGarry, J.D.; Foster, D.W. Regulation of hepatic fatty acid oxidation and ketone body production. Annu. Rev. Biochem. 1980, 49, 395–420. [Google Scholar] [CrossRef]
  152. Dąbek, A.; Wojtala, M.; Pirola, L.; Balcerczyk, A. Modulation of Cellular Biochemistry, Epigenetics and Metabolomics by Ketone Bodies. Implications of the Ketogenic Diet in the Physiology of the Organism and Pathological States. Nutrients 2020, 12, 788. [Google Scholar] [CrossRef]
  153. Ramadhian, M.R. INHERITED VARIATIONS IN DRUGS EFFECT INDEPENDENT IN PHARMACOKINETIC: POLYMORPHISM IN PHASE II BIOTRANSFORMATION ENZYMES. JUKE Unila 2014, 4, 254–268. [Google Scholar]
  154. Hwang, C.Y.; Choe, W.; Yoon, K.S.; Ha, J.; Kim, S.S.; Yeo, E.J.; Kang, I. Molecular Mechanisms for Ketone Body Metabolism, Signaling Functions, and Therapeutic Potential in Cancer. Nutrients 2022, 14, 4932. [Google Scholar] [CrossRef]
  155. Puchalska, P.; Crawford, P.A. Metabolic and Signaling Roles of Ketone Bodies in Health and Disease. Annu. Rev. Nutr. 2021, 41, 49–77. [Google Scholar] [CrossRef]
  156. Lam, T.K.T.; Carpentier, A.; Lewis, G.F.; Van de Werve, G.; Fantus, I.G.; Giacca, A. Mechanisms of the free fatty acid-induced increase in hepatic glucose production. Am. J. Physiol. Endocrinol. Metab. 2003, 284, E863–E873. [Google Scholar] [CrossRef]
  157. Batenburg, J.J.; Olson, M.S. Regulation of pyruvate dehydrogenase by fatty acid in isolated rat liver mitochondria. J. Biol. Chem. 1976, 251, 1364–1370. [Google Scholar] [CrossRef]
  158. Pougovkina, O.; Te Brinke, H.; Ofman, R.; Van Cruchten, A.G.; Kulik, W.; Wanders, R.J.A.; Houten, S.M.; De Boer, V.C.J. Mitochondrial protein acetylation is driven by acetyl-CoA from fatty acid oxidation. Hum. Mol. Genet. 2014, 23, 3513–3522. [Google Scholar] [CrossRef]
  159. Sodji, Q.H.; Kornacki, J.R.; Mrksich, M.; Oyelere, A.K. Chapter 15—In Vitro Histone Deacetylase Activity Screening: Making a Case for Better Assays; Zheng, Y.G., Ed.; Academic Press: Boston, MA, USA, 2015; pp. 319–332. ISBN 978-0-12-801080-8. [Google Scholar]
  160. Hirschey, M.D.; Shimazu, T.; Goetzman, E.; Jing, E.; Schwer, B.; Lombard, D.B.; Grueter, C.A.; Harris, C.; Biddinger, S.; Ilkayeva, O.R.; et al. SIRT3 regulates mitochondrial fatty-acid oxidation by reversible enzyme deacetylation. Nature 2010, 464, 121–125. [Google Scholar] [CrossRef]
  161. Bharathi, S.S.; Zhang, Y.; Mohsen, A.W.; Uppala, R.; Balasubramani, M.; Schreiber, E.; Uechi, G.; Beck, M.E.; Vockley, J.; Rardin, M.J.; et al. Sirtuin 3 (SIRT3) protein regulates long-chain acyl-CoA dehydrogenase by deacetylating conserved lysines near the active site. J. Biol. Chem. 2013, 288, 33837–33847. [Google Scholar] [CrossRef]
  162. Shimazu, T.; Hirschey, M.D.; Hua, L.; Dittenhafer-Reed, K.E.; Schwer, B.; Lombard, D.B.; Li, Y.; Bunkenborg, J.; Alt, F.W.; Denu, J.M.; et al. SIRT3 deacetylates mitochondrial 3-hydroxy-3-methylglutaryl CoA synthase 2 and regulates ketone body production. Cell Metab. 2010, 12, 654–661. [Google Scholar] [CrossRef]
  163. Nakagawa, T.; Lomb, D.J.; Haigis, M.C.; Guarente, L. SIRT5 Deacetylates carbamoyl phosphate synthetase 1 and regulates the urea cycle. Cell 2009, 137, 560–570. [Google Scholar] [CrossRef]
  164. Yu, W.; Lin, Y.; Yao, J.; Huang, W.; Lei, Q.; Xiong, Y.; Zhao, S.; Guan, K.-L. Lysine 88 acetylation negatively regulates ornithine carbamoyltransferase activity in response to nutrient signals. J. Biol. Chem. 2009, 284, 13669–13675. [Google Scholar] [CrossRef]
  165. Hallows, W.C.; Yu, W.; Smith, B.C.; Devires, M.K.; Ellinger, J.J.; Someya, S.; Shortreed, M.R.; Prolla, T.; Markley, J.L.; Smith, L.M.; et al. Sirt3 Promotes the Urea Cycle and Fatty Acid Oxidation during Dietary Restriction. Mol. Cell 2011, 41, 139–149. [Google Scholar] [CrossRef]
  166. Walker, V. Ammonia metabolism and hyperammonemic disorders. Adv. Clin. Chem. 2014, 67, 73–150. [Google Scholar] [CrossRef] [PubMed]
  167. Fahien, L.A.; Schooler, J.M.; Gehred, G.A.; Cohen, P.P. Studies on the Mechanism of Action of Acetylglutamate as an Activator of Carbamyl Phosphate Synthetase. J. Biol. Chem. 1964, 239, 1935–1941. [Google Scholar] [CrossRef]
  168. Nissim, I.; Daikhin, Y.; Nissim, I.; Luhovyy, B.; Horyn, O.; Wehrli, S.L.; Yudkoff, M. Agmatine stimulates hepatic fatty acid oxidation: A possible mechanism for up-regulation of ureagenesis. J. Biol. Chem. 2006, 281, 8486–8496. [Google Scholar] [CrossRef]
  169. Ribas, G.S.; Lopes, F.F.; Deon, M.; Vargas, C.R. Hyperammonemia in Inherited Metabolic Diseases. Cell. Mol. Neurobiol. 2022, 42, 2593–2610. [Google Scholar] [CrossRef] [PubMed]
  170. Merritt, J.L.; MacLeod, E.; Jurecka, A.; Hainline, B. Clinical manifestations and management of fatty acid oxidation disorders. Rev. Endocr. Metab. Disord. 2020, 21, 479–493. [Google Scholar] [CrossRef]
  171. Ribas, G.S.; Vargas, C.R. Evidence that Oxidative Disbalance and Mitochondrial Dysfunction are Involved in the Pathophysiology of Fatty Acid Oxidation Disorders. Cell. Mol. Neurobiol. 2022, 42, 521–532. [Google Scholar] [CrossRef] [PubMed]
  172. Fromenty, B.; Pessayre, D. Inhibition of mitochondrial beta-oxidation as a mechanism of hepatotoxicity. Pharmacol. Ther. 1995, 67, 101–154. [Google Scholar] [CrossRef]
  173. Amaral, A.U.; Cecatto, C.; Da Silva, J.C.; Wajner, A.; Godoy, K.D.S.; Ribeiro, R.T.; Wajner, M. cis-4-Decenoic and decanoic acids impair mitochondrial energy, redox and Ca(2+) homeostasis and induce mitochondrial permeability transition pore opening in rat brain and liver: Possible implications for the pathogenesis of MCAD deficiency. Biochim. Biophys. Acta 2016, 1857, 1363–1372. [Google Scholar] [CrossRef]
  174. Lopaschuk, G.D.; Karwi, Q.G.; Tian, R.; Wende, A.R.; Abel, E.D. Cardiac Energy Metabolism in Heart Failure. Circ. Res. 2021, 128, 1487–1513. [Google Scholar] [CrossRef]
  175. Karwi, Q.G.; Biswas, D.; Pulinilkunnil, T.; Lopaschuk, G.D. Myocardial Ketones Metabolism in Heart Failure. J. Card. Fail. 2020, 26, 998–1005. [Google Scholar] [CrossRef]
  176. Dong, S.; Qian, L.; Cheng, Z.; Chen, C.; Wang, K.; Hu, S.; Zhang, X.; Wu, T. Lactate and Myocadiac Energy Metabolism. Front. Physiol. 2021, 12, 715081. [Google Scholar] [CrossRef] [PubMed]
  177. Fillmore, N.; Mori, J.; Lopaschuk, G.D. Mitochondrial fatty acid oxidation alterations in heart failure, ischaemic heart disease and diabetic cardiomyopathy. Br. J. Pharmacol. 2014, 171, 2080–2090. [Google Scholar] [CrossRef] [PubMed]
  178. De Loof, M.; Renguet, E.; Ginion, A.; Bouzin, C.; Horman, S.; Beauloye, C.; Bertrand, L.; Bultot, L. Enhanced protein acetylation initiates fatty acid-mediated inhibition of cardiac glucose transport. Am. J. Physiol. Circ. Physiol. 2023, 324, H305–H317. [Google Scholar] [CrossRef] [PubMed]
  179. Olkowicz, M.; Tomczyk, M.; Debski, J.; Tyrankiewicz, U.; Przyborowski, K.; Borkowski, T.; Zabielska-Kaczorowska, M.; Szupryczynska, N.; Kochan, Z.; Smeda, M.; et al. Enhanced cardiac hypoxic injury in atherogenic dyslipidaemia results from alterations in the energy metabolism pattern. Metabolism 2021, 114, 154400. [Google Scholar] [CrossRef]
  180. Jaswal, J.S.; Keung, W.; Wang, W.; Ussher, J.R.; Lopaschuk, G.D. Targeting fatty acid and carbohydrate oxidation—A novel therapeutic intervention in the ischemic and failing heart. Biochim. Biophys. Acta Mol. Cell Res. 2011, 1813, 1333–1350. [Google Scholar] [CrossRef] [PubMed]
  181. Sack, M.N.; Rader, T.A.; Park, S.; Bastin, J.; McCune, S.A.; Kelly, D.P. Fatty acid oxidation enzyme gene expression is downregulated in the failing heart. Circulation 1996, 94, 2837–2842. [Google Scholar] [CrossRef]
  182. Wang, W.; Zhang, L.; Battiprolu, P.K.; Fukushima, A.; Nguyen, K.; Milner, K.; Gupta, A.; Altamimi, T.; Byrne, N.; Mori, J.; et al. Malonyl CoA Decarboxylase Inhibition Improves Cardiac Function Post-Myocardial Infarction. JACC Basic Transl. Sci. 2019, 4, 385–400. [Google Scholar] [CrossRef]
  183. Shao, D.; Kolwicz, S.C.; Wang, P.; Roe, N.D.; Villet, O.; Nishi, K.; Hsu, Y.W.A.; Flint, G.V.; Caudal, A.; Wang, W.; et al. Increasing Fatty Acid Oxidation Prevents High-Fat Diet-Induced Cardiomyopathy Through Regulating Parkin-Mediated Mitophagy. Circulation 2020, 142, 983–997. [Google Scholar] [CrossRef]
  184. Liu, Z.L.; Ding, J.; McMillen, T.S.; Villet, O.; Tian, R.; Shao, D. Enhancing fatty acid oxidation negatively regulates PPARs signaling in the heart. J. Mol. Cell. Cardiol. 2020, 146, 1–11. [Google Scholar] [CrossRef]
  185. Peterson, L.R.; Herrero, P.; Schechtman, K.B.; Racette, S.B.; Waggoner, A.D.; Kisrieva-Ware, Z.; Dence, C.; Klein, S.; Marsala, J.A.; Meyer, T.; et al. Effect of Obesity and Insulin Resistance on Myocardial Substrate Metabolism and Efficiency in Young Women. Circulation 2004, 109, 2191–2196. [Google Scholar] [CrossRef] [PubMed]
  186. Mazumder, P.K.; O’Neill, B.T.; Roberts, M.W.; Buchanan, J.; Yun, U.J.; Cooksey, R.C.; Boudina, S.; Abel, E.D. Impaired cardiac efficiency and increased fatty acid oxidation in insulin-resistant ob/ob mouse hearts. Diabetes 2004, 53, 2366–2374. [Google Scholar] [CrossRef] [PubMed]
  187. Boudina, S.; Abel, E.D. Diabetic cardiomyopathy revisited. Circulation 2007, 115, 3213–3223. [Google Scholar] [CrossRef] [PubMed]
  188. Zhou, Y.T.; Grayburn, P.; Karim, A.; Shimabukuro, M.; Higa, M.; Baetens, D.; Orci, L.; Unger, R.H. Lipotoxic heart disease in obese rats: Implications for human obesity. Proc. Natl. Acad. Sci. USA 2000, 97, 1784–1789. [Google Scholar] [CrossRef] [PubMed]
  189. Goldenberg, J.R.; Carley, A.N.; Ji, R.; Zhang, X.; Fasano, M.; Schulze, P.C.; Lewandowski, E.D. Preservation of Acyl Coenzyme A Attenuates Pathological and Metabolic Cardiac Remodeling through Selective Lipid Trafficking. Circulation 2019, 139, 2765–2777. [Google Scholar] [CrossRef]
  190. Knottnerus, S.J.G.; Bleeker, J.C.; Wüst, R.C.I.; Ferdinandusse, S.; IJlst, L.; Wijburg, F.A.; Wanders, R.J.A.; Visser, G.; Houtkooper, R.H. Disorders of mitochondrial long-chain fatty acid oxidation and the carnitine shuttle. Rev. Endocr. Metab. Disord. 2018, 19, 93–106. [Google Scholar] [CrossRef] [PubMed]
  191. Mayell, S.J.; Edwards, L.; Reynolds, F.E.; Chakrapani, A.B. Late presentation of medium-chain acyl-CoA dehydrogenase deficiency. J. Inherit. Metab. Dis. 2007, 30, 104. [Google Scholar] [CrossRef]
  192. El-Gharbawy, A.; Goldstein, A. Mitochondrial Fatty Acid Oxidation Disorders Associated with Cardiac Disease. Curr. Pathobiol. Rep. 2017, 5, 259–270. [Google Scholar] [CrossRef]
  193. Bonnet, D.; Martin, D.; De Lonlay, P.; Villain, E.; Jouvet, P.; Rabier, D.; Brivet, M.; Saudubray, J.M. Arrhythmias and conduction defects as presenting symptoms of fatty acid oxidation disorders in children. Circulation 1999, 100, 2248–2253. [Google Scholar] [CrossRef]
  194. Sklirou, E.; Alodaib, A.N.; Dobrowolski, S.F.; Mohsen, A.W.A.; Vockley, J. Physiological Perspectives on the Use of Triheptanoin as Anaplerotic Therapy for Long Chain Fatty Acid Oxidation Disorders. Front. Genet. 2021, 11, 598760. [Google Scholar] [CrossRef] [PubMed]
  195. Vockley, J.; Charrow, J.; Ganesh, J.; Eswara, M.; Diaz, G.A.; McCracken, E.; Conway, R.; Enns, G.M.; Starr, J.; Wang, R.; et al. Triheptanoin treatment in patients with pediatric cardiomyopathy associated with long chain-fatty acid oxidation disorders. Mol. Genet. Metab. 2016, 119, 223–231. [Google Scholar] [CrossRef]
  196. Vockley, J.; Burton, B.; Berry, G.; Longo, N.; Phillips, J.; Sanchez-Valle, A.; Chapman, K.; Tanpaiboon, P.; Grunewald, S.; Murphy, E.; et al. Effects of triheptanoin (UX007) in patients with long-chain fatty acid oxidation disorders: Results from an open-label, long-term extension study. J. Inherit. Metab. Dis. 2021, 44, 253–263. [Google Scholar] [CrossRef]
  197. Vockley, J.; Burton, B.; Berry, G.; Longo, N.; Phillips, J.; Sanchez-Valle, A.; Chapman, K.; Tanpaiboon, P.; Grunewald, S.; Murphy, E.; et al. OP017: Triheptanoin for the treatment of Long-Chain Fatty Acid Disorders (LC-FAOD): Final results of an open-label, long-term extension study. Genet. Med. 2022, 24, S349. [Google Scholar] [CrossRef]
  198. Hamilton-Craig, I.; Yudi, M.; Johnson, L.; Jayasinghe, R. Fenofibrate therapy in carnitine palmitoyl transferase type 2 deficiency. Case Rep. Med. 2012, 2012, 1–4. [Google Scholar] [CrossRef]
  199. Ørngreen, M.C.; Vissing, J.; Laforét, P. No effect of bezafibrate in patients with CPTII and VLCAD deficiencies. J. Inherit. Metab. Dis. 2015, 38, 373–374. [Google Scholar] [CrossRef]
  200. Koves, T.R.; Ussher, J.R.; Noland, R.C.; Slentz, D.; Mosedale, M.; Ilkayeva, O.; Bain, J.; Stevens, R.; Dyck, J.R.B.; Newgard, C.B.; et al. Mitochondrial Overload and Incomplete Fatty Acid Oxidation Contribute to Skeletal Muscle Insulin Resistance. Cell Metab. 2008, 7, 45–56. [Google Scholar] [CrossRef]
  201. Gavin, T.P.; Ernst, J.M.; Kwak, H.B.; Caudill, S.E.; Reed, M.A.; Garner, R.T.; Nie, Y.; Weiss, J.A.; Pories, W.J.; Dar, M.; et al. High incomplete skeletal muscle fatty acid oxidation explains low muscle insulin sensitivity in poorly controlled T2D. J. Clin. Endocrinol. Metab. 2018, 103, 882–889. [Google Scholar] [CrossRef] [PubMed]
  202. Mengeste, A.M.; Rustan, A.C.; Lund, J. Skeletal muscle energy metabolism in obesity. Obesity 2021, 29, 1582–1595. [Google Scholar] [CrossRef] [PubMed]
  203. Fritzen, A.M.; Lundsgaard, A.M.; Kiens, B. Tuning fatty acid oxidation in skeletal muscle with dietary fat and exercise. Nat. Rev. Endocrinol. 2020, 16, 683–696. [Google Scholar] [CrossRef] [PubMed]
  204. Simoneau, J.; Veerkamp, J.H.; Turcotte, L.P.; Kelley, D.E. Markers of capacity to utilize fatty acids in human skeletal muscle: Relation to insulin resistance and obesity and effects of weight loss. FASEB J. 1999, 13, 2051–2060. [Google Scholar] [CrossRef] [PubMed]
  205. Bhargava, P.; Schnellmann, R.G. Mitochondrial energetics in the kidney. Nat. Rev. Nephrol. 2017, 13, 629–646. [Google Scholar] [CrossRef]
  206. Rong, Q.; Han, B.; Li, Y.; Yin, H.; Li, J.; Hou, Y. Berberine Reduces Lipid Accumulation by Promoting Fatty Acid Oxidation in Renal Tubular Epithelial Cells of the Diabetic Kidney. Front. Pharmacol. 2022, 12, 729384. [Google Scholar] [CrossRef]
  207. Li, B.; Hao, J.; Zeng, J.; Sauter, E.R. SnapShot: FABP Functions. Cell 2020, 182, 1066.e1. [Google Scholar] [CrossRef]
  208. Li, J.; Yang, Y.; Li, Q.; Wei, S.; Zhou, Y.; Yu, W.; Xue, L.; Zhou, L.; Shen, L.; Lu, G.; et al. STAT6 contributes to renal fibrosis by modulating PPARα-mediated tubular fatty acid oxidation. Cell Death Dis. 2022, 13, 1–11. [Google Scholar] [CrossRef]
  209. Simon, N.; Hertig, A. Alteration of Fatty Acid Oxidation in Tubular Epithelial Cells: From Acute Kidney Injury to Renal Fibrogenesis. Front. Med. 2015, 2, 52. [Google Scholar] [CrossRef]
  210. Jang, H.S.; Noh, M.R.; Kim, J.; Padanilam, B.J. Defective Mitochondrial Fatty Acid Oxidation and Lipotoxicity in Kidney Diseases. Front. Med. 2020, 7, 65. [Google Scholar] [CrossRef]
  211. Khan, S.; Gaivin, R.; Abramovich, C.; Boylan, M.; Calles, J.; Schelling, J.R. Fatty acid transport protein-2 regulates glycemic control and diabetic kidney disease progression. JCI Insight 2020, 5, e136845. [Google Scholar] [CrossRef]
  212. Miguel, V.; Tituaña, J.; Ignacio Herrero, J.; Herrero, L.; Serra, D.; Cuevas, P.; Barbas, C.; Puyol, D.R.; Márquez-Expósito, L.; Ruiz-Ortega, M.; et al. Renal tubule Cpt1a overexpression protects from kidney fibrosis by restoring mitochondrial homeostasis. J. Clin. Investig. 2021, 131, e140695. [Google Scholar] [CrossRef]
  213. Idrovo, J.P.; Yang, W.L.; Nicastro, J.; Coppa, G.F.; Wang, P. Stimulation of carnitine palmitoyltransferase 1 improves renal function and attenuates tissue damage after ischemia/reperfusion. J. Surg. Res. 2012, 177, 157–164. [Google Scholar] [CrossRef] [PubMed]
  214. Dhillon, P.; Park, J.; Hurtado del Pozo, C.; Li, L.; Doke, T.; Huang, S.; Zhao, J.; Kang, H.M.; Shrestra, R.; Balzer, M.S.; et al. The Nuclear Receptor ESRRA Protects from Kidney Disease by Coupling Metabolism and Differentiation. Cell Metab. 2021, 33, 379–394.e8. [Google Scholar] [CrossRef] [PubMed]
  215. Nicholson, R.J.; Ramkumar, N.; Summers, S.A. Gain of ‘FAOnction’, Loss of Fibrosis. Trends Endocrinol. Metab. 2021, 32, 333–334. [Google Scholar] [CrossRef] [PubMed]
  216. Zhou, D.; Liu, Y. Understanding the mechanisms of kidney fibrosis. Nat. Rev. Nephrol. 2016, 12, 68–70. [Google Scholar] [CrossRef]
  217. Kang, H.M.; Ahn, S.H.; Choi, P.; Ko, Y.A.; Han, S.H.; Chinga, F.; Park, A.S.D.; Tao, J.; Sharma, K.; Pullman, J.; et al. Defective fatty acid oxidation in renal tubular epithelial cells has a key role in kidney fibrosis development. Nat. Med. 2015, 21, 37–46. [Google Scholar] [CrossRef]
  218. Morel, J.D.; Sleiman, M.B.; Li, T.Y.; von Alvensleben, G.; Bachmann, A.M.; Hofer, D.; Broeckx, E.; Ma, J.Y.; Carreira, V.; Chen, T.; et al. Mitochondrial and NAD+ metabolism predict recovery from acute kidney injury in a diverse mouse population. JCI insight 2023, 8, e164626. [Google Scholar] [CrossRef]
  219. Gao, Z.; Chen, X. Fatty Acid β-Oxidation in Kidney Diseases: Perspectives on Pathophysiological Mechanisms and Therapeutic Opportunities. Front. Pharmacol. 2022, 13, 805281. [Google Scholar] [CrossRef]
  220. Bougarne, N.; Weyers, B.; Desmet, S.J.; Deckers, J.; Ray, D.W.; Staels, B.; De Bosscher, K. Molecular actions of PPARα in lipid metabolism and inflammation. Endocr. Rev. 2018, 39, 760–802. [Google Scholar] [CrossRef]
  221. Li, S.; Wu, P.; Yarlagadda, P.; Vadjunec, N.M.; Proia, A.D.; Harris, R.A.; Portilla, D. PPARα ligand protects during cisplatin-induced acute renal failure by preventing inhibition of renal FAO and PDC activity. Am. J. Physiol. Ren. Physiol. 2004, 286, F572–F580. [Google Scholar] [CrossRef]
  222. Qiu, Y.; Hu, X.; Xu, C.; Lu, C.; Cao, R.; Xie, Y.; Yang, J. Ketogenic diet alleviates renal fibrosis in mice by enhancing fatty acid oxidation through the free fatty acid receptor 3 pathway. Front. Nutr. 2023, 10, 397. [Google Scholar] [CrossRef]
  223. Panov, A.V.; Mayorov, V.I.; Dikalova, A.E.; Dikalov, S.I. Long-Chain and Medium-Chain Fatty Acids in Energy Metabolism of Murine Kidney Mitochondria. Int. J. Mol. Sci. 2023, 24, 379. [Google Scholar] [CrossRef]
  224. Geng, J.; Liu, Y.; Dai, H.; Wang, C. Fatty Acid Metabolism and Idiopathic Pulmonary Fibrosis. Front. Physiol. 2022, 12, 794629. [Google Scholar] [CrossRef]
  225. Gu, L.; Larson Casey, J.L.; Andrabi, S.A.; Lee, J.H.; Meza-Perez, S.; Randall, T.D.; Carter, A.B. Mitochondrial calcium uniporter regulates PGC-1α expression to mediate metabolic reprogramming in pulmonary fibrosis. Redox Biol. 2019, 26, 101307. [Google Scholar] [CrossRef]
  226. Zheng, S.; Wang, Q.; D’Souza, V.; Bartis, D.; Dancer, R.; Parekh, D.; Gao, F.; Lian, Q.; Jin, S.; Thickett, D.R. ResolvinD1 stimulates epithelial wound repair and inhibits TGF-β-induced EMT whilst reducing fibroproliferation and collagen production. Lab. Investig. 2018, 98, 130–140. [Google Scholar] [CrossRef] [PubMed]
  227. Parks, B.W.; Black, L.L.; Zimmerman, K.A.; Metz, A.E.; Steele, C.; Murphy-Ullrich, J.E.; Kabarowski, J.H. CD36, but not G2A, modulates efferocytosis, infl ammation, and fibrosis following bleomycin-induced lung injury. J. Lipid Res. 2013, 54, 1114–1123. [Google Scholar] [CrossRef] [PubMed]
  228. Langhans, W.; Leitner, C.; Arnold, M. Dietary fat sensing via fatty acid oxidation in enterocytes: Possible role in the control of eating. Am. J. Physiol. Regul. Integr. Comp. Physiol. 2011, 300, 554–565. [Google Scholar] [CrossRef]
  229. Venegas, D.P.; De La Fuente, M.K.; Landskron, G.; González, M.J.; Quera, R.; Dijkstra, G.; Harmsen, H.J.M.; Faber, K.N.; Hermoso, M.A. Short chain fatty acids (SCFAs)mediated gut epithelial and immune regulation and its relevance for inflammatory bowel diseases. Front. Immunol. 2019, 10, 424615. [Google Scholar] [CrossRef]
  230. Roediger, W.E.W.; Millard, S. Selective inhibition of fatty acid oxidation in colonocytes by ibuprofen: A cause of colitis? Gut 1995, 36, 55–59. [Google Scholar] [CrossRef] [PubMed]
  231. Malandrino, M.I.; Fucho, R.; Weber, M.; Calderon-Dominguez, M.; Mir, J.F.; Valcarcel, L.; Escoté, X.; Gómez-Serrano, M.; Peral, B.; Salvadó, L.; et al. Enhanced fatty acid oxidation in adipocytes and macrophages reduces lipid-induced triglyceride accumulation and inflammation. Am. J. Physiol. Endocrinol. Metab. 2015, 308, E756–E769. [Google Scholar] [CrossRef] [PubMed]
  232. Torchon, E.; Ray, R.; Hulver, M.W.; McMillan, R.P.; Voy, B.H. Fasting rapidly increases fatty acid oxidation in white adipose tissue of young broiler chickens. Adipocyte 2017, 6, 33–39. [Google Scholar] [CrossRef] [PubMed]
  233. Gonzalez-Hurtado, E.; Lee, J.; Choi, J.; Wolfgang, M.J. Fatty acid oxidation is required for active and quiescent brown adipose tissue maintenance and thermogenic programing. Mol. Metab. 2018, 7, 45–56. [Google Scholar] [CrossRef] [PubMed]
  234. Schönfeld, P.; Reiser, G. Why does brain metabolism not favor burning of fatty acids to provide energy? Reflections on disadvantages of the use of free fatty acids as fuel for brain. J. Cereb. Blood Flow Metab. 2013, 33, 1493–1499. [Google Scholar] [CrossRef]
  235. Ebert, D.; Haller, R.G.; Walton, M.E. Energy contribution of octanoate to intact rat brain metabolism measured by 13C nuclear magnetic resonance spectroscopy. J. Neurosci. 2003, 23, 5928–5935. [Google Scholar] [CrossRef] [PubMed]
  236. Dhopeshwarkar, G.A.; Subramanian, C.; Mead, J.F. Rapid uptke of [1-14C] acetate by the adult rat brain 15 seconds after carotid injection. Biochim. Biophys. Acta (BBA)/Lipids Lipid Metab. 1971, 248, 41–47. [Google Scholar] [CrossRef]
  237. Gnaedinger, J.M.; Miller, J.C.; Latker, C.H.; Rapoport, S.I. Cerebral metabolism of plasma [14C]palmitate in awake, adult rat: Subcellular localization. Neurochem. Res. 1988, 13, 21–29. [Google Scholar] [CrossRef]
  238. Panov, A.; Orynbayeva, Z.; Vavilin, V.; Lyakhovich, V. Fatty acids in energy metabolism of the central nervous system. Biomed Res. Int. 2014, 2014, 1–22. [Google Scholar] [CrossRef]
  239. Edmond, J.; Robbins, R.A.; Bergstrom, J.D.; Cole, R.A.; de Vellis, J. Capacity for substrate utilization in oxidative metabolism by neurons, astrocytes, and oligodendrocytes from developing brain in primary culture. J. Neurosci. Res. 1987, 18, 551–561. [Google Scholar] [CrossRef]
  240. Takahashi, S. Metabolic Compartmentalization between Astroglia and Neurons in Physiological and Pathophysiological Conditions of the Neurovascular Unit; Blackwell Publishing: Hoboken, NJ, USA, 2020; Volume 40, pp. 121–137. [Google Scholar]
  241. Ioannou, M.S. Current Insights into Fatty Acid Transport in the Brain. J. Membr. Biol. 2020, 253, 375–379. [Google Scholar] [CrossRef]
  242. Szrok-jurga, S.; Turyn, J.; Hebanowska, A.; Swierczynski, J.; Czumaj, A.; Sledzinski, T.; Stelmanska, E. The Role of Acyl-CoA β -Oxidation in Brain Metabolism and Neurodegenerative Diseases. Int. J. Mol. Sci. 2023, 24, 13977. [Google Scholar] [CrossRef]
  243. Mallick, R.; Duttaroy, A.K. Modulation of endothelium function by fatty acids. Mol. Cell. Biochem. 2022, 477, 15–38. [Google Scholar] [CrossRef]
  244. Schoors, S.; Bruning, U.; Missiaen, R.; Queiroz, K.C.S.; Borgers, G.; Elia, I.; Zecchin, A.; Cantelmo, A.R.; Christen, S.; Goveia, J.; et al. Fatty acid carbon is essential for dNTP synthesis in endothelial cells. Nature 2015, 520, 192–197. [Google Scholar] [CrossRef] [PubMed]
  245. Kalucka, J.; Bierhansl, L.; Conchinha, N.V.; Missiaen, R.; Elia, I.; Brüning, U.; Scheinok, S.; Treps, L.; Cantelmo, A.R.; Dubois, C.; et al. Quiescent Endothelial Cells Upregulate Fatty Acid β-Oxidation for Vasculoprotection via Redox Homeostasis. Cell Metab. 2018, 28, 881–894. [Google Scholar] [CrossRef] [PubMed]
  246. Świerczyński, J.; Ścisłowski, P.; Aleksandrowicz, Z. Oxidation of palmitoyl-carnitine by mitochondria isolated from human term placenta. Biochem. Med. 1976, 16, 55–58. [Google Scholar] [CrossRef]
  247. Shekhawat, P.; Bennett, M.J.; Sadovsky, Y.; Nelson, D.M.; Rakheja, D.; Strauss, A.W. Human placenta metabolizes fatty acids: Implications for fetal fatty acid oxidation disorders and maternal liver diseases. Am. J. Physiol. Endocrinol. Metab. 2003, 284, E1098–E1105. [Google Scholar] [CrossRef] [PubMed]
  248. Rakheja, D.; Bennett, M.J.; Foster, B.M.; Domiati-Saad, R.; Rogers, B.B. Evidence for Fatty Acid Oxidation in Human Placenta, and the Relationship of Fatty Acid Oxidation Enzyme Activities with Gestational Age. Placenta 2002, 23, 447–450. [Google Scholar] [CrossRef]
  249. Oey, N.A.; den Boer, M.E.J.; Ruiter, J.P.N.; Wanders, R.J.A.; Duran, M.; Waterham, H.R.; Boer, K.; van der Post, J.A.M.; Wijburg, F.A. High activity of fatty acid oxidation enzymes in human placenta: Implications for fetal-maternal disease. J. Inherit. Metab. Dis. 2003, 26, 385–392. [Google Scholar] [CrossRef]
  250. Shin, E.K.; Kang, H.Y.; Yang, H.; Jung, E.M.; Jeung, E.B. The Regulation of Fatty Acid Oxidation in Human Preeclampsia. Reprod. Sci. 2016, 23, 1422–1433. [Google Scholar] [CrossRef]
  251. Mendez-Figueroa, H.; Chien, E.K.; Ji, H.; Nesbitt, N.L.; Bharathi, S.S.; Goetzman, E. Effects of labor on placental fatty acid β oxidation. J. Matern. Neonatal Med. 2013, 26, 150–154. [Google Scholar] [CrossRef]
  252. Powell, T.L.; Barner, K.; Madi, L.; Armstrong, M.; Manke, J.; Uhlson, C.; Jansson, T.; Ferchaud-Roucher, V. Sex-specific responses in placental fatty acid oxidation, esterification and transfer capacity to maternal obesity. Biochim. Biophys. Acta Mol. Cell Biol. Lipids 2021, 1866, 158861. [Google Scholar] [CrossRef]
  253. Hulme, C.H.; Nicolaou, A.; Murphy, S.A.; Heazell, A.E.P.; Myers, J.E.; Westwood, M. The effect of high glucose on lipid metabolism in the human placenta. Sci. Rep. 2019, 9, 14114. [Google Scholar] [CrossRef]
  254. Pompéia, C.; Lopes, L.R.; Miyasaka, C.K.; Procópio, J.; Sannomiya, P.; Curi, R. Effect of fatty acids on leukocyte function. Brazilian J. Med. Biol. Res. = Rev. Bras. Pesqui. Med. Biol. 2000, 33, 1255–1268. [Google Scholar] [CrossRef]
  255. Pendergast, D.R.; Fisher, N.M.; Meksawan, K.; Doubrava, M.; Vladutiu, G.D. The distribution of white blood cell fat oxidation in health and disease. J. Inherit. Metab. Dis. 2004, 27, 89–99. [Google Scholar] [CrossRef]
  256. Schaefer, J.; Pourfarzam, M.; Bartlett, K.; Jackson, S.; Turnbull, D.M. Fatty acid oxidation in peripheral blood cells: Characterization and use for the diagnosis of defects of fatty acid oxidation. Pediatr. Res. 1995, 37, 354–360. [Google Scholar] [CrossRef]
  257. Stenlid, R.; Olsson, D.; Cen, J.; Manell, H.; Haglind, C.; Chowdhury, A.I.; Bergsten, P.; Nordenström, A.; Halldin, M. Altered mitochondrial metabolism in peripheral blood cells from patients with inborn errors of β-oxidation. Clin. Transl. Sci. 2022, 15, 182–194. [Google Scholar] [CrossRef]
  258. Tu, L.N.; Zhao, A.H.; Hussein, M.; Stocco, D.M.; Selvaraj, V. Translocator Protein (TSPO) Affects Mitochondrial Fatty Acid Oxidation in Steroidogenic Cells. Endocrinology 2016, 157, 1110–1121. [Google Scholar] [CrossRef]
  259. Park-Min, K.-H. Metabolic reprogramming in osteoclasts. Semin. Immunopathol. 2019, 41, 565–572. [Google Scholar] [CrossRef]
  260. Da, W.; Tao, L.; Zhu, Y. The Role of Osteoclast Energy Metabolism in the Occurrence and Development of Osteoporosis. Front. Endocrinol. 2021, 12, 675385. [Google Scholar] [CrossRef]
  261. Dodds, R.A.; Gowen, M.; Bradbeer, J.N. Microcytophotometric analysis of human osteoclast metabolism: Lack of activity in certain oxidative pathways indicates inability to sustain biosynthesis during resorption. J. Histochem. Cytochem. Off. J. Histochem. Soc. 1994, 42, 599–606. [Google Scholar] [CrossRef]
  262. Lemma, S.; Sboarina, M.; Porporato, P.E.; Zini, N.; Sonveaux, P.; Di Pompo, G.; Baldini, N.; Avnet, S. Energy metabolism in osteoclast formation and activity. Int. J. Biochem. Cell Biol. 2016, 79, 168–180. [Google Scholar] [CrossRef]
  263. Koduru, S.V.; Sun, B.-H.; Walker, J.M.; Zhu, M.; Simpson, C.; Dhodapkar, M.; Insogna, K.L. The contribution of cross-talk between the cell-surface proteins CD36 and CD47-TSP-1 in osteoclast formation and function. J. Biol. Chem. 2018, 293, 15055–15069. [Google Scholar] [CrossRef] [PubMed]
  264. Dawodu, D.; Patecki, M.; Hegermann, J.; Dumler, I.; Haller, H.; Kiyan, Y. oxLDL inhibits differentiation and functional activity of osteoclasts via scavenger receptor-A mediated autophagy and cathepsin K secretion. Sci. Rep. 2018, 8, 11604. [Google Scholar] [CrossRef]
  265. Bellissimo, M.P.; Roberts, J.L.; Jones, D.P.; Liu, K.H.; Taibl, K.R.; Uppal, K.; Weitzmann, M.N.; Pacifici, R.; Drissi, H.; Ziegler, T.R.; et al. Metabolomic Associations with Serum Bone Turnover Markers. Nutrients 2020, 12, 3161. [Google Scholar] [CrossRef] [PubMed]
  266. Kushwaha, P.; Alekos, N.S.; Kim, S.P.; Li, Z.; Wolfgang, M.J.; Riddle, R.C. Mitochondrial fatty acid β-oxidation is important for normal osteoclast formation in growing female mice. Front. Physiol. 2022, 13, 997358. [Google Scholar] [CrossRef]
  267. Huang, Z.; Luo, R.; Yang, L.; Chen, H.; Zhang, X.; Han, J.; Wang, H.; Zhou, Z.; Wang, Z.; Shao, L. CPT1A-Mediated Fatty Acid Oxidation Promotes Precursor Osteoclast Fusion in Rheumatoid Arthritis. Front. Immunol. 2022, 13, 1–15. [Google Scholar] [CrossRef] [PubMed]
  268. Yaney, G.C.; Corkey, B.E. Fatty acid metabolism and insulin secretion in pancreatic beta cells. Diabetologia 2003, 46, 1297–1312. [Google Scholar] [CrossRef]
  269. Berne, C. The metabolism of lipids in mouse pancreatic islets. The oxidation of fatty acids and ketone bodies. Biochem. J. 1975, 152, 661–666. [Google Scholar] [CrossRef]
  270. Malaisse, W.J. Insulin secretion: Multifactorial regulation for a single process of release. Diabetologia 1973, 9, 167–173. [Google Scholar] [CrossRef]
  271. Haber, E.P.; Ximenes, H.M.A.; Procópio, J.; Carvalho, C.R.O.; Curi, R.; Carpinelli, A.R. Pleiotropic effects of fatty acids on pancreatic beta-cells. J. Cell Physiol. 2003, 194, 1–12. [Google Scholar] [CrossRef]
  272. Nolan, C.J.; Madiraju, M.S.R.; Delghingaro-Augusto, V.; Peyot, M.-L.; Prentki, M. Fatty Acid Signaling in the β-Cell and Insulin Secretion. Diabetes 2006, 55, S16–S23. [Google Scholar] [CrossRef]
  273. El-Assaad, W.; Buteau, J.; Peyot, M.-L.; Nolan, C.; Roduit, R.; Hardy, S.; Joly, E.; Dbaibo, G.; Rosenberg, L.; Prentki, M. Saturated Fatty Acids Synergize with Elevated Glucose to Cause Pancreatic β-Cell Death. Endocrinology 2003, 144, 4154–4163. [Google Scholar] [CrossRef]
  274. Gremlich, S.; Bonny, C.; Waeber, G.; Thorens, B. Fatty Acids Decrease IDX-1 Expression in Rat Pancreatic Islets and Reduce GLUT2, Glucokinase, Insulin, and Somatostatin Levels*. J. Biol. Chem. 1997, 272, 30261–30269. [Google Scholar] [CrossRef]
  275. Hellemans, K.; Kerckhofs, K.; Hannaert, J.C.; Martens, G.; Van Veldhoven, P.; Pipeleers, D. Peroxisome proliferator-activated receptor α-retinoid X receptor agonists induce beta-cell protection against palmitate toxicity. FEBS J. 2007, 274, 6094–6105. [Google Scholar] [CrossRef]
  276. Elsner, M.; Gehrmann, W.; Lenzen, S. Peroxisome-Generated Hydrogen Peroxide as Important Mediator of Lipotoxicity in Insulin-Producing Cells. Diabetes 2010, 60, 200–208. [Google Scholar] [CrossRef] [PubMed]
  277. Hanahan, D.; Weinberg, R.A. Hallmarks of cancer: The next generation. Cell 2011, 144, 646–674. [Google Scholar] [CrossRef]
  278. Carracedo, A.; Cantley, L.C.; Pandolfi, P.P. Cancer metabolism: Fatty acid oxidation in the limelight. Nat. Rev. Cancer 2013, 13, 227–232. [Google Scholar] [CrossRef]
  279. Swierczynski, J.; Hebanowska, A.; Sledzinski, T. Role of abnormal lipid metabolism in development, progression, diagnosis and therapy of pancreatic cancer. World J. Gastroenterol. 2014, 20, 2279–2303. [Google Scholar] [CrossRef] [PubMed]
  280. Pakiet, A.; Kobiela, J.; Stepnowski, P.; Sledzinski, T.; Mika, A. Changes in lipids composition and metabolism in colorectal cancer: A review. Lipids Health Dis. 2019, 18, 1–21. [Google Scholar] [CrossRef] [PubMed]
  281. Agarwala, P.K.; Aneja, R.; Kapoor, S. Lipidomic landscape in cancer: Actionable insights for membrane-based therapy and diagnoses. Med. Res. Rev. 2022, 42, 983–1018. [Google Scholar] [CrossRef]
  282. Shi, J.; Fu, H.; Jia, Z.; He, K.; Fu, L.; Wang, W. High Expression of CPT1A Predicts Adverse Outcomes: A Potential Therapeutic Target for Acute Myeloid Leukemia. EBioMedicine 2016, 14, 55. [Google Scholar] [CrossRef]
  283. Liu, P.P.; Liu, J.; Jiang, W.Q.; Carew, J.S.; Ogasawara, M.A.; Pelicano, H.; Croce, C.M.; Estrov, Z.; Xu, R.H.; Keating, M.J.; et al. Elimination of Chronic Lymphocytic Leukemia Cells in Stromal Microenvironment by Targeting CPT with an Anti-Angina Drug Perhexiline. Oncogene 2016, 35, 5663. [Google Scholar] [CrossRef]
  284. Wu, Y.; Hurren, R.; MacLean, N.; Gronda, M.; Jitkova, Y.; Sukhai, M.A.; Minden, M.D.; Schimmer, A.D. Carnitine transporter CT2 (SLC22A16) is over-expressed in acute myeloid leukemia (AML) and target knockdown reduces growth and viability of AML cells. Apoptosis 2015, 20, 1099–1108. [Google Scholar] [CrossRef] [PubMed]
  285. Padanad, M.S.; Konstantinidou, G.; Venkateswaran, N.; Melegari, M.; Rindhe, S.; Mitsche, M.; Yang, C.; Batten, K.; Huffman, K.E.; Liu, J.; et al. Fatty Acid Oxidation Mediated by Acyl-CoA Synthetase Long Chain 3 Is Required for Mutant KRAS Lung Tumorigenesis. Cell Rep. 2016, 16, 1614–1628. [Google Scholar] [CrossRef]
  286. Shao, H.; Mohamed, E.M.; Xu, G.G.; Waters, M.; Jing, K.; Ma, Y.; Zhang, Y.; Spiegel, S.; Idowu, M.O.; Fang, X. Carnitine palmitoyltransferase 1A functions to repress FoxO transcription factors to allow cell cycle progression in ovarian cancer. Oncotarget 2016, 7, 3832. [Google Scholar] [CrossRef] [PubMed]
  287. Mika, A.; Pakiet, A.; Czumaj, A.; Kaczynski, Z.; Liakh, I.; Kobiela, J.; Perdyan, A.; Adrych, K.; Makarewicz, W.; Sledzinski, T. Decreased Triacylglycerol Content and Elevated Contents of Cell Membrane Lipids in Colorectal Cancer Tissue: A Lipidomic Study. J. Clin. Med. 2020, 9, 1095. [Google Scholar] [CrossRef]
  288. Wang, Y.; Zeng, Z.; Lu, J.; Wang, Y.; Liu, Z.; He, M.; Zhao, Q.; Wang, Z.; Li, T.; Lu, Y.; et al. CPT1A-mediated fatty acid oxidation promotes colorectal cancer cell metastasis by inhibiting anoikis. Oncogene 2018, 37, 6025–6040. [Google Scholar] [CrossRef]
  289. Jiang, N.; Xie, B.; Xiao, W.; Fan, M.; Xu, S.; Duan, Y.; Hamsafar, Y.; Evans, A.C.; Huang, J.; Zhou, W.; et al. Fatty acid oxidation fuels glioblastoma radioresistance with CD47-mediated immune evasion. Nat. Commun. 2022, 13, 1–20. [Google Scholar] [CrossRef] [PubMed]
  290. Chen, W.C.; Wang, C.Y.; Hung, Y.H.; Weng, T.Y.; Yen, M.C.; Lai, M.D. Systematic analysis of gene expression alterations and clinical outcomes for long-chain acyl-coenzyme A synthetase family in cancer. PLoS ONE 2016, 11, e0155660. [Google Scholar] [CrossRef] [PubMed]
  291. Huang, W.; Jin, Y.; Yuan, Y.; Bai, C.; Wu, Y.; Zhu, H.; Lu, S. Validation and target gene screening of hsa-miR-205 in lung squamous cell carcinoma. Chin. Med. J. 2014, 127, 272–278. [Google Scholar] [PubMed]
  292. Sánchez-Martínez, R.; Cruz-Gil, S.; de Cedrón, M.G.; Álvarez-Fernández, M.; Vargas, T.; Molina, S.; García, B.; Herranz, J.; Moreno-Rubio, J.; Reglero, G.; et al. A link between lipid metabolism and epithelial-mesenchymal transition provides a target for colon cancer therapy. Oncotarget 2015, 6, 38719–38736. [Google Scholar] [CrossRef] [PubMed]
  293. Cui, M.; Wang, Y.; Sun, B.; Xiao, Z.; Ye, L.; Zhang, X. MiR-205 modulates abnormal lipid metabolism of hepatoma cells via targeting acyl-CoA synthetase long-chain family member 1 (ACSL1) mRNA. Biochem. Biophys. Res. Commun. 2014, 444, 270–275. [Google Scholar] [CrossRef] [PubMed]
  294. Cui, M.; Xiao, Z.; Wang, Y.; Zheng, M.; Song, T.; Cai, X.; Sun, B.; Ye, L.; Zhang, X. Long noncoding RNA HULC modulates abnormal lipid metabolism in hepatoma cells through an mir-9-mediated RXRA signaling pathway. Cancer Res. 2015, 75, 846–857. [Google Scholar] [CrossRef] [PubMed]
  295. Wang, J.; Scholtens, D.; Holko, M.; Ivancic, D.; Lee, O.; Hu, H.; Chatterton, R.T.; Sullivan, M.E.; Hansen, N.; Bethke, K.; et al. Lipid metabolism genes in contralateral unaffected breast and estrogen receptor status of breast cancer. Cancer Prev. Res. 2013, 6, 321–330. [Google Scholar] [CrossRef] [PubMed]
  296. Pei, Z.; Fraisl, P.; Shi, X.; Gabrielson, E.; Forss-Petter, S.; Berger, J.; Watkins, P.A. Very Long-Chain Acyl-CoA Synthetase 3: Overexpression and Growth Dependence in Lung Cancer. PLoS ONE 2013, 8, e69392. [Google Scholar] [CrossRef]
  297. Ye, X.; Zhang, Y.; Wang, X.; Li, Y.; Gao, Y. Tumor-suppressive functions of long-chain acyl-CoA synthetase 4 in gastric cancer. IUBMB Life 2016, 68, 320–327. [Google Scholar] [CrossRef] [PubMed]
  298. Monaco, M.E.; Creighton, C.J.; Lee, P.; Zou, X.; Topham, M.K.; Stafforini, D.M. Expression of Long-chain Fatty Acyl-CoA Synthetase 4 in Breast and Prostate Cancers Is Associated with Sex Steroid Hormone Receptor Negativity 1. Transl. Oncol. 2010, 3, 91–98. [Google Scholar] [CrossRef]
  299. Cao, Y.; Pearman, A.T.; Zimmerman, G.A.; McIntyre, T.M.; Prescott, S.M. Intracellular unesterified arachidonic acid signals apoptosis. Proc. Natl. Acad. Sci. USA 2000, 97, 11280–11285. [Google Scholar] [CrossRef]
  300. Wu, X.; Li, Y.; Wang, J.; Wen, X.; Marcus, M.T.; Daniels, G.; Zhang, D.Y.; Ye, F.; Wang, L.H.; Du, X.; et al. Long Chain Fatty Acyl-CoA Synthetase 4 Is a Biomarker for and Mediator of Hormone Resistance in Human Breast Cancer. PLoS ONE 2013, 8, e77060. [Google Scholar] [CrossRef]
  301. Hu, C.; Chen, L.; Jiang, Y.; Li, Y.; Wang, S. The effect of fatty acid-CoA ligase 4 on the growth of hepatic cancer cells. Cancer Biol. Ther. 2008, 7, 133–136. [Google Scholar] [CrossRef]
  302. Wu, X.; Deng, F.; Li, Y.; Daniels, G.; Du, X.; Ren, Q.; Wang, J.; Wang, L.H.; Yang, Y.; Zhang, V.; et al. ACSL4 promotes prostate cancer growth, invasion and hormonal resistance. Oncotarget 2015, 6, 44849–44863. [Google Scholar] [CrossRef]
  303. Cao, Y.; Dave, K.B.; Doan, T.P.; Prescott, S.M. Fatty acid CoA ligase 4 is up-regulated in colon adenocarcinoma. Cancer Res. 2001, 61, 8429–8434. [Google Scholar] [PubMed]
  304. Sung, Y.K.; Hwang, S.Y.; Park, M.K.; Bae, H.I.; Kim, W.H.; Kim, J.C.; Kim, M. Fatty acid-CoA ligase 4 is overexpressed in human hepatocellular carcinoma. Cancer Sci. 2003, 94, 421–424. [Google Scholar] [CrossRef] [PubMed]
  305. Gassler, N.; Schneider, A.; Kopitz, J.; Schnölzer, M.; Obermüller, N.; Kartenbeck, J.; Otto, H.F.; Autschbach, F. Impaired Expression of Acyl-CoA-Synthetase 5 in Epithelial Tumors of the Small Intestine. Hum. Pathol. 2003, 34, 1048–1052. [Google Scholar] [CrossRef]
  306. Pitule, P.; Vycital, O.; Bruha, J.; Novak, P.; Hosek, P.; Treska, V.; Hlavata, I.; Soucek, P.; Kralickova, M.; Liska, V. Differential expression and prognostic role of selected genes in colorectal cancer patients. Anticancer Res. 2013, 33, 4855–4866. [Google Scholar]
  307. Gaisa, N.T.; Reinartz, A.; Schneider, U.; Klaus, C.; Heidenreich, A.; Jakse, G.; Kaemmerer, E.; Klinkhammer, B.M.; Knuechel, R.; Gassler, N. Levels of acyl-Coenzyme A synthetase 5 in urothelial cells and corresponding neoplasias reflect cellular differentiation. Histol. Histopathol. 2013, 28, 353–364. [Google Scholar] [CrossRef]
  308. Liu, J.; Li, Y.; Xiao, Q.; Li, Y.; Peng, Y.; Gan, Y.; Shu, G.; Yi, H.; Yin, G. Identification of CPT2 as a prognostic biomarker by integrating the metabolism-associated gene signature in colorectal cancer. BMC Cancer 2022, 22, 1038. [Google Scholar] [CrossRef]
  309. Wang, L.; Li, C.; Song, Y.; Yan, Z.K. Inhibition of carnitine palmitoyl transferase 1A-induced fatty acid oxidation suppresses cell progression in gastric cancer. Arch. Biochem. Biophys. 2020, 696, 108664. [Google Scholar] [CrossRef]
  310. Abudurexiti, M.; Zhu, W.; Wang, Y.; Wang, J.; Xu, W.; Huang, Y.; Zhu, Y.; Shi, G.; Zhang, H.; Zhu, Y.; et al. Targeting CPT1B as a potential therapeutic strategy in castration-resistant and enzalutamide-resistant prostate cancer. Prostate 2020, 80, 950–961. [Google Scholar] [CrossRef] [PubMed]
  311. Vantaku, V.; Dong, J.; Ambati, C.R.; Perera, D.; Donepudi, S.R.; Amara, C.S.; Putluri, V.; Ravi, S.S.; Robertson, M.J.; Piyarathna, D.W.B.; et al. Multi-omics Integration Analysis Robustly Predicts High-Grade Patient Survival and Identifies CPT1B Effect on Fatty Acid Metabolism in Bladder Cancer. Clin. Cancer Res. 2019, 25, 3689–3701. [Google Scholar] [CrossRef]
  312. Chen, T.; Wu, G.; Hu, H.; Wu, C. Enhanced fatty acid oxidation mediated by CPT1C promotes gastric cancer progression. J. Gastrointest. Oncol. 2020, 11, 695–707. [Google Scholar] [CrossRef]
  313. Zaugg, K.; Yao, Y.; Reilly, P.T.; Kannan, K.; Kiarash, R.; Mason, J.; Huang, P.; Sawyer, S.K.; Fuerth, B.; Faubert, B.; et al. Carnitine palmitoyltransferase 1C promotes cell survival and tumor growth under conditions of metabolic stress. Genes Dev. 2011, 25, 1041–1051. [Google Scholar] [CrossRef] [PubMed]
  314. Wang, R.; Cheng, Y.; Su, D.; Gong, B.; He, X.; Zhou, X.; Pang, Z.; Cheng, L.; Chen, Y.; Yao, Z. Cpt1c regulated by AMPK promotes papillary thyroid carcinomas cells survival under metabolic stress conditions. J. Cancer 2017, 8, 3675–3681. [Google Scholar] [CrossRef] [PubMed]
  315. Lin, M.; Lv, D.; Zheng, Y.; Wu, M.; Xu, C.; Zhang, Q.; Wu, L. Downregulation of CPT2 promotes tumorigenesis and chemoresistance to cisplatin in hepatocellular carcinoma. OncoTargets Ther. 2018, 11, 3101–3110. [Google Scholar] [CrossRef] [PubMed]
  316. Zhang, X.; Zhang, Z.; Liu, S.; Li, J.; Wu, L.; Lv, X.; Xu, J.; Chen, B.; Zhao, S.; Yang, H. CPT2 down-regulation promotes tumor growth and metastasis through inducing ROS/NFκB pathway in ovarian cancer. Transl. Oncol. 2021, 14, 101023. [Google Scholar] [CrossRef]
  317. Birkenkamp-Demtroder, K.; Christensen, L.L.; Olesen, S.H.; Frederiksen, C.M.; Laiho, P.; Aaltonen, L.A.; Laurberg, S.; Sørensen, F.B.; Hagemann, R.; Ørntoft, T.F. Gene expression in colorectal cancer. Cancer Res. 2002, 62, 4352–4363. [Google Scholar]
  318. Ren, H.; Li, W.; Liu, X.; Li, S.; Guo, H.; Wang, W.; Zhao, N. Identification and Validation of an 6-Metabolism-Related Gene Signature and Its Correlation With Immune Checkpoint in Hepatocellular Carcinoma. Front. Oncol. 2021, 11, 783934. [Google Scholar] [CrossRef]
  319. Cui, J.; Yi, G.; Li, J.; Li, Y.; Qian, D. Increased EHHADH Expression Predicting Poor Survival of Osteosarcoma by Integrating Weighted Gene Coexpression Network Analysis and Experimental Validation. Biomed Res. Int. 2021, 2021, 9917060. [Google Scholar] [CrossRef] [PubMed]
  320. Tang, Z.; Shen, Q.; Xie, H.; Zhou, X.; Li, J.; Feng, J.; Liu, H.; Wang, W.; Zhang, S.; Ni, S. Elevated expression of FABP3 and FABP4 cooperatively correlates with poor prognosis in non-small cell lung cancer (NSCLC). Oncotarget 2016, 7, 46253–46262. [Google Scholar] [CrossRef]
  321. Guo, Y.; Wang, Z.W.; Su, W.H.; Chen, J.; Wang, Y.L. Prognostic Value and Immune Infiltrates of ABCA8 and FABP4 in Stomach Adenocarcinoma. Biomed Res. Int. 2020, 2020, 1–12. [Google Scholar] [CrossRef] [PubMed]
  322. Zhong, C.Q.; Zhang, X.P.; Ma, N.; Zhang, E.B.; Li, J.J.; Jiang, Y.B.; Gao, Y.Z.; Yuan, Y.M.; Lan, S.Q.; Xie, D.; et al. FABP4 suppresses proliferation and invasion of hepatocellular carcinoma cells and predicts a poor prognosis for hepatocellular carcinoma. Cancer Med. 2018, 7, 2629–2640. [Google Scholar] [CrossRef]
  323. Kim, S.I.; Jung, M.; Dan, K.; Lee, S.; Lee, C.; Kim, H.S.; Chung, H.H.; Kim, J.W.; Park, N.H.; Song, Y.S.; et al. Proteomic discovery of biomarkers to predict prognosis of high-grade serous ovarian carcinoma. Cancers 2020, 12, 790. [Google Scholar] [CrossRef] [PubMed]
  324. Luo, Y.; Yang, Z.; Li, D.; Liu, Z.; Yang, L.; Zou, Q.; Yuan, Y. LDHB and fabp4 are associated with progression and poor prognosis of pancreatic ductal adenocarcinomas. Appl. Immunohistochem. Mol. Morphol. 2017, 25, 351–357. [Google Scholar] [CrossRef] [PubMed]
  325. Lin, R.; Zhang, H.; Yuan, Y.; He, Q.; Zhou, J.; Li, S.; Sun, Y.; Li, D.Y.; Qiu, H.B.; Wang, W.; et al. Fatty acid oxidation controls CD8+Tissue-resident memory t-cell survival in gastric adenocarcinoma. Cancer Immunol. Res. 2020, 8, 479–492. [Google Scholar] [CrossRef] [PubMed]
  326. Holzbeierlein, J.; Lal, P.; LaTulippe, E.; Smith, A.; Satagopan, J.; Zhang, L.; Ryan, C.; Smith, S.; Scher, H.; Scardino, P.; et al. Gene Expression Analysis of Human Prostate Carcinoma during Hormonal Therapy Identifies Androgen-Responsive Genes and Mechanisms of Therapy Resistance. Am. J. Pathol. 2004, 164, 217–227. [Google Scholar] [CrossRef] [PubMed]
  327. Shen, C.; Song, Y.H.; Xie, Y.; Wang, X.; Wang, Y.; Wang, C.; Liu, S.; Xue, S.L.; Li, Y.; Liu, B.; et al. Downregulation of HADH promotes gastric cancer progression via Akt signaling pathway. Oncotarget 2017, 8, 76279–76289. [Google Scholar] [CrossRef]
  328. Du, Z.; Zhang, X.; Gao, W.; Yang, J. Differentially expressed genes PCCA, ECHS1, and HADH are potential prognostic biomarkers for gastric cancer. Sci. Prog. 2021, 104, 1–14. [Google Scholar] [CrossRef]
  329. Zhang, B.; Wu, Q.; Wang, Z.; Xu, R.; Hu, X.; Sun, Y.; Wang, Q.; Ju, F.; Ren, S.; Zhang, C.; et al. The promising novel biomarkers and candidate small molecule drugs in kidney renal clear cell carcinoma: Evidence from bioinformatics analysis of high-throughput data. Mol. Genet. Genom. Med. 2019, 7, e607. [Google Scholar] [CrossRef]
  330. Jiang, H.; Chen, H.; Wan, P.; Chen, N. Decreased expression of HADH is related to poor prognosis and immune infiltration in kidney renal clear cell carcinoma. Genomics 2021, 113, 3556–3564. [Google Scholar] [CrossRef]
  331. Ren, J.; Feng, J.; Song, W.; Wang, C.; Ge, Y.; Fu, T. Development and validation of a metabolic gene signature for predicting overall survival in patients with colon cancer. Clin. Exp. Med. 2020, 20, 535–544. [Google Scholar] [CrossRef]
  332. Wei, J.; Xie, Q.; Liu, X.; Wan, C.; Wu, W.; Fang, K.; Yao, Y.; Cheng, P.; Deng, D.; Liu, Z. Identification the prognostic value of glutathione peroxidases expression levels in acute myeloid leukemia. Ann. Transl. Med. 2020, 8, 678. [Google Scholar] [CrossRef]
  333. Mamtani, M.; Kulkarni, H. Association of HADHA expression with the risk of breast cancer: Targeted subset analysis and meta-analysis of microarray data. BMC Res. Notes 2012, 5, 25. [Google Scholar] [CrossRef] [PubMed]
  334. Huang, D.; Li, T.; Li, X.; Zhang, L.; Sun, L.; He, X.; Zhong, X.; Jia, D.; Song, L.; Semenza, G.L.; et al. HIF-1-mediated suppression of acyl-CoA dehydrogenases and fatty acid oxidation is critical for cancer progression. Cell Rep. 2014, 8, 1930–1942. [Google Scholar] [CrossRef]
  335. Puca, F.; Yu, F.; Bartolacci, C.; Pettazzoni, P.; Carugo, A.; Huang-Hobbs, E.; Liu, J.; Zanca, C.; Carbone, F.; Del Poggetto, E.; et al. Medium-chain acyl-coa dehydrogenase protects mitochondria from lipid peroxidation in glioblastoma. Cancer Discov. 2021, 11, 2904–2923. [Google Scholar] [CrossRef]
  336. Su, Y.W.; Wu, P.S.; Lin, S.H.; Huang, W.Y.; Kuo, Y.S.; Lin, H.P. Prognostic value of the overexpression of fatty acid metabolism-related enzymes in Squamous cell Carcinoma of the head and neck. Int. J. Mol. Sci. 2020, 21, 6851. [Google Scholar] [CrossRef]
  337. Carracedo, A.; Weiss, D.; Leliaert, A.K.; Bhasin, M.; de Boer, V.C.J.; Laurent, G.; Adams, A.C.; Sundvall, M.; Song, S.J.; Ito, K.; et al. A metabolic prosurvival role for PML in breast cancer. J. Clin. Investig. 2012, 122, 3088–3100. [Google Scholar] [CrossRef] [PubMed]
  338. Samudio, I.; Fiegl, M.; Andreeff, M. Mitochondrial uncoupling and the Warburg effect: Molecular basis for the reprogramming of cancer cell metabolism. Cancer Res. 2009, 69, 2163–2166. [Google Scholar] [CrossRef] [PubMed]
  339. Schafer, Z.T.; Grassian, A.R.; Song, L.; Jiang, Z.; Gerhart-Hines, Z.; Irie, H.Y.; Gao, S.; Puigserver, P.; Brugge, J.S. Antioxidant and oncogene rescue of metabolic defects caused by loss of matrix attachment. Nature 2009, 461, 109–113. [Google Scholar] [CrossRef]
  340. Caro, P.; Kishan, A.U.; Norberg, E.; Stanley, I.A.; Chapuy, B.; Ficarro, S.B.; Polak, K.; Tondera, D.; Gounarides, J.; Yin, H.; et al. Metabolic signatures uncover distinct targets in molecular subsets of diffuse large B cell lymphoma. Cancer Cell 2012, 22, 547–560. [Google Scholar] [CrossRef]
  341. Ma, Y.; Temkin, S.M.; Hawkridge, A.M.; Guo, C.; Wang, W.; Wang, X.Y.; Fang, X. Fatty acid oxidation: An emerging facet of metabolic transformation in cancer. Cancer Lett. 2018, 435, 92. [Google Scholar] [CrossRef]
  342. Jeon, S.M.; Chandel, N.S.; Hay, N. AMPK regulates NADPH homeostasis to promote tumour cell survival during energy stress. Nature 2012, 485, 661–665. [Google Scholar] [CrossRef] [PubMed]
  343. Wang, Y.-P.; Zhou, L.-S.; Zhao, Y.-Z.; Wang, S.-W.; Chen, L.-L.; Liu, L.-X.; Ling, Z.-Q.; Hu, F.-J.; Sun, Y.-P.; Zhang, J.-Y.; et al. Regulation of G6PD acetylation by SIRT2 and KAT9 modulates NADPH homeostasis and cell survival during oxidative stress. EMBO J. 2014, 33, 1304–1320. [Google Scholar] [CrossRef]
  344. Pike, L.S.; Smift, A.L.; Croteau, N.J.; Ferrick, D.A.; Wu, M. Inhibition of fatty acid oxidation by etomoxir impairs NADPH production and increases reactive oxygen species resulting in ATP depletion and cell death in human glioblastoma cells. Biochim. Biophys. Acta 2011, 1807, 726–734. [Google Scholar] [CrossRef]
  345. Wen, Y.A.; Xing, X.; Harris, J.W.; Zaytseva, Y.Y.; Mitov, M.I.; Napier, D.L.; Weiss, H.L.; Mark Evers, B.; Gao, T. Adipocytes activate mitochondrial fatty acid oxidation and autophagy to promote tumor growth in colon cancer. Cell Death Dis. 2017, 8, e2593. [Google Scholar] [CrossRef]
  346. Wang, Y.Y.; Attané, C.; Milhas, D.; Dirat, B.; Dauvillier, S.; Guerard, A.; Gilhodes, J.; Lazar, I.; Alet, N.; Laurent, V.; et al. Mammary adipocytes stimulate breast cancer invasion through metabolic remodeling of tumor cells. JCI Insight 2017, 2, e87489. [Google Scholar] [CrossRef]
  347. Lazar, I.; Clement, E.; Dauvillier, S.; Milhas, D.; Ducoux-Petit, M.; LeGonidec, S.; Moro, C.; Soldan, V.; Dalle, S.; Balor, S.; et al. Adipocyte Exosomes Promote Melanoma Aggressiveness through Fatty Acid Oxidation: A Novel Mechanism Linking Obesity and Cancer. Cancer Res. 2016, 76, 4051–4057. [Google Scholar] [CrossRef]
  348. Huang, J.; Duran, A.; Reina-Campos, M.; Valencia, T.; Castilla, E.A.; Müller, T.D.; Tschöp, M.H.; Moscat, J.; Diaz-Meco, M.T. Adipocyte p62/SQSTM1 Suppresses Tumorigenesis through Opposite Regulations of Metabolism in Adipose Tissue and Tumor. Cancer Cell 2018, 33, 770–784.e6. [Google Scholar] [CrossRef]
  349. Ostrom, Q.T.; Cioffi, G.; Gittleman, H.; Patil, N.; Waite, K.; Kruchko, C.; Barnholtz-Sloan, J.S. CBTRUS Statistical Report: Primary Brain and Other Central Nervous System Tumors Diagnosed in the United States in 2012–2016. Neuro-Oncology 2019, 21, v1–v100. [Google Scholar] [CrossRef]
  350. Sebastiano, M.R.; Konstantinidou, G. Targeting long chain acyl-coa synthetases for cancer therapy. Int. J. Mol. Sci. 2019, 20, 3624. [Google Scholar] [CrossRef]
  351. Tung, S.; Shi, Y.; Wong, K.; Zhu, F.; Gorczynski, R.; Laister, R.C.; Minden, M.; Blechert, A.K.; Genzel, Y.; Reichl, U.; et al. PPARα and fatty acid oxidation mediate glucocorticoid resistance in chronic lymphocytic leukemia. Blood 2013, 122, 969–980. [Google Scholar] [CrossRef]
  352. Hermanova, I.; Arruabarrena-Aristorena, A.; Valis, K.; Nuskova, H.; Alberich-Jorda, M.; Fiser, K.; Fernandez-Ruiz, S.; Kavan, D.; Pecinova, A.; Niso-Santano, M.; et al. Pharmacological inhibition of fatty-acid oxidation synergistically enhances the effect of l-asparaginase in childhood ALL cells. Leukemia 2016, 30, 209–218. [Google Scholar] [CrossRef]
  353. Kitajima, S.; Yoshida, A.; Kohno, S.; Li, F.; Suzuki, S.; Nagatani, N.; Nishimoto, Y.; Sasaki, N.; Muranaka, H.; Wan, Y.; et al. The RB-IL-6 axis controls self-renewal and endocrine therapy resistance by fine-tuning mitochondrial activity. Oncogene 2017, 36, 5145–5157. [Google Scholar] [CrossRef] [PubMed]
  354. Ma, A.P.Y.; Yeung, C.L.S.; Tey, S.K.; Mao, X.; Wong, S.W.K.; Ng, T.H.; Ko, F.C.F.; Kwong, E.M.L.; Tang, A.H.N.; Ng, I.O.L.; et al. Suppression of ACADM-Mediated Fatty Acid Oxidation Promotes Hepatocellular Carcinoma via Aberrant CAV1/SREBP1 Signaling. Cancer Res. 2021, 81, 3679–3692. [Google Scholar] [CrossRef] [PubMed]
  355. Sánchez-Martínez, R.; Cruz-Gil, S.; García-Álvarez, M.S.; Reglero, G.; De Molina, A.R. Complementary ACSL isoforms contribute to a non-Warburg advantageous energetic status characterizing invasive colon cancer cells. Sci. Rep. 2017, 7, 11143. [Google Scholar] [CrossRef] [PubMed]
  356. Orlando, U.D.; Castillo, A.F.; Dattilo, M.A.; Solano, A.R.; Maloberti, P.M.; Podesta, E.J. Acyl-CoA synthetase-4, a new regulator of mTOR and a potential therapeutic target for enhanced estrogen receptor function in receptor-positive and -negative breast cancer. Oncotarget 2015, 6, 42632–42650. [Google Scholar] [CrossRef]
  357. Castillo, A.F.; Orlando, U.D.; Maloberti, P.M.; Prada, J.G.; Dattilo, M.A.; Solano, A.R.; Bigi, M.M.; Rios Medrano, M.A.; Torres, M.T.; Indo, S.; et al. New inhibitor targeting Acyl-CoA synthetase 4 reduces breast and prostate tumor growth, therapeutic resistance and steroidogenesis. Cell. Mol. Life Sci. 2020, 78, 2893–2910. [Google Scholar] [CrossRef] [PubMed]
  358. Mashima, T.; Sato, S.; Okabe, S.; Miyata, S.; Matsuura, M.; Sugimoto, Y.; Tsuruo, T.; Seimiya, H. Acyl-CoA synthetase as a cancer survival factor: Its inhibition enhances the efficacy of etoposide. Cancer Sci. 2009, 100, 1556–1562. [Google Scholar] [CrossRef]
  359. Zhang, L.; Lv, J.; Chen, C.; Wang, X. Roles of acyl-CoA synthetase long-chain family member 5 and colony stimulating factor 2 in inhibition of palmitic or stearic acids in lung cancer cell proliferation and metabolism. Cell Biol. Toxicol. 2021, 37, 15–34. [Google Scholar] [CrossRef]
  360. Pei, Z.; Sun, P.; Huang, P.; Lal, B.; Laterra, J.; Watkins, P.A. Acyl-CoA synthetase VL3 knockdown inhibits human glioma cell proliferation and tumorigenicity. Cancer Res. 2009, 69, 9175–9182. [Google Scholar] [CrossRef]
  361. Lee, E.A.; Angka, L.; Rota, S.G.; Hanlon, T.; Mitchell, A.; Hurren, R.; Wang, X.M.; Gronda, M.; Boyaci, E.; Bojko, B.; et al. Targeting mitochondria with avocatin B induces selective leukemia cell death. Cancer Res. 2015, 75, 2478–2488. [Google Scholar] [CrossRef]
  362. Camarda, R.; Zhou, A.Y.; Kohnz, R.A.; Balakrishnan, S.; Mahieu, C.; Anderton, B.; Eyob, H.; Kajimura, S.; Tward, A.; Krings, G.; et al. Inhibition of fatty acid oxidation as a therapy for MYC-overexpressing triple-negative breast cancer. Nat. Med. 2016, 22, 427. [Google Scholar] [CrossRef]
  363. Samudio, I.; Harmancey, R.; Fiegl, M.; Kantarjian, H.; Konopleva, M.; Korchin, B.; Kaluarachchi, K.; Bornmann, W.; Duvvuri, S.; Taegtmeyer, H.; et al. Pharmacologic inhibition of fatty acid oxidation sensitizes human leukemia cells to apoptosis induction. J. Clin. Investig. 2010, 120, 142. [Google Scholar] [CrossRef]
  364. Schlaepfer, I.R.; Rider, L.; Rodrigues, L.U.; Gijón, M.A.; Pac, C.T.; Romero, L.; Cimic, A.; Sirintrapun, S.J.; Glodé, L.M.; Eckel, R.H.; et al. Lipid catabolism via CPT1 as a therapeutic target for prostate cancer. Mol. Cancer Ther. 2014, 13, 2361. [Google Scholar] [CrossRef] [PubMed]
  365. Hossain, F.; Al-Khami, A.A.; Wyczechowska, D.; Hernandez, C.; Zheng, L.; Reiss, K.; Del Valle, L.; Trillo-Tinoco, J.; Maj, T.; Zou, W.; et al. Inhibition of Fatty Acid Oxidation Modulates Immunosuppressive Functions of Myeloid-Derived Suppressor Cells and Enhances Cancer Therapies. Cancer Immunol. Res. 2015, 3, 1236–1247. [Google Scholar] [CrossRef] [PubMed]
  366. Dheeraj, A.; Agarwal, C.; Schlaepfer, I.R.; Raben, D.; Singh, R.; Agarwal, R.; Deep, G. A novel approach to target hypoxic cancer cells via combining β-oxidation inhibitor etomoxir with radiation. Hypoxia 2018, 6, 23–33. [Google Scholar] [CrossRef] [PubMed]
  367. Mascagna, D.; Ghanem, G.; Morandini, R.; D’Ischia, M.; Misuraca, G.; Lejeune, F.; Prota, G. Synthesis and cytotoxic properties of new N-substituted 4-am...: Melanoma Research. Melanoma Res. 1992, 2, 25–32. [Google Scholar] [CrossRef]
  368. Pucci, S.; Zonetti, M.J.; Fisco, T.; Polidoro, C.; Bocchinfuso, G.; Palleschi, A.; Novelli, G.; Spagnoli, L.G.; Mazzarelli, P. Carnitine palmitoyl transferase-1A (CPT1A): A new tumor specific target in human breast cancer. Oncotarget 2016, 7, 19982–19996. [Google Scholar] [CrossRef] [PubMed]
  369. Berge, K.; Tronstad, K.J.; Bohov, P.; Madsen, L.; Berge, R.K. Impact of mitochondrial β-oxidation in fatty acid-mediated inhibition of glioma cell proliferation. J. Lipid Res. 2003, 44, 118–127. [Google Scholar] [CrossRef]
  370. Wang, Y.; Lu, J.H.; Wang, F.; Wang, Y.N.; He, M.M.; Wu, Q.N.; Lu, Y.X.; Yu, H.E.; Chen, Z.H.; Zhao, Q.; et al. Inhibition of fatty acid catabolism augments the efficacy of oxaliplatin-based chemotherapy in gastrointestinal cancers. Cancer Lett. 2020, 473, 74–89. [Google Scholar] [CrossRef]
  371. Liu, X.; Feng, R.; Du, L. The role of enoyl-CoA hydratase short chain 1 and peroxiredoxin 3 in PP2-induced apoptosis in human breast cancer MCF-7 cells. FEBS Lett. 2010, 584, 3185–3192. [Google Scholar] [CrossRef]
  372. Hernlund, E.; Ihrlund, L.S.; Khan, O.; Ates, Y.O.; Linder, S.; Panaretakis, T.; Shoshan, M.C. Potentiation of chemotherapeutic drugs by energy metabolism inhibitors 2-deoxyglucose and etomoxir. Int. J. Cancer 2008, 123, 476–483. [Google Scholar] [CrossRef]
  373. Yao, C.H.; Liu, G.Y.; Wang, R.; Moon, S.H.; Gross, R.W.; Patti, G.J. Identifying off-target effects of etomoxir reveals that carnitine palmitoyltransferase i is essential for cancer cell proliferation independent of β-oxidation. PLoS Biol. 2018, 16, e2003782. [Google Scholar] [CrossRef] [PubMed]
  374. Conti, R.; Mannucci, E.; Pessotto, P.; Tassoni, E.; Carminati, P.; Giannessi, F.; Arduini, A. Selective reversible inhibition of liver carnitine palmitoyl-transferase 1 by teglicar reduces gluconeogenesis and improves glucose homeostasis. Diabetes 2011, 60, 644–651. [Google Scholar] [CrossRef] [PubMed]
  375. Nencioni, A.; Caffa, I.; Cortellino, S.; Longo, V.D. Fasting and cancer: Molecular mechanisms and clinical application. Nat. Rev. Cancer 2018, 18, 707–719. [Google Scholar] [CrossRef]
  376. Lien, E.C.; Westermark, A.M.; Zhang, Y.; Yuan, C.; Li, Z.; Lau, A.N.; Sapp, K.M.; Wolpin, B.M.; Vander Heiden, M.G. Low glycaemic diets alter lipid metabolism to influence tumour growth. Nature 2021, 599, 302–307. [Google Scholar] [CrossRef]
  377. Dmitrieva-Posocco, O.; Wong, A.C.; Lundgren, P.; Golos, A.M.; Descamps, H.C.; Dohnalová, L.; Cramer, Z.; Tian, Y.; Yueh, B.; Eskiocak, O.; et al. β-Hydroxybutyrate suppresses colorectal cancer. Nature 2022, 605, 160–165. [Google Scholar] [CrossRef]
  378. Abolhassani, R.; Berg, E.; Tenenbaum, G.; Israel, M. Inhibition of SCOT and Ketolysis Decreases Tumor Growth and Inflammation in the Lewis Cancer Model. Jap. J. Oncol. Clin. Res. 2022, 3, 1–12. [Google Scholar]
  379. Mahajan, A.; Spracklen, C.N.; Zhang, W.; Ng, M.C.Y.; Petty, L.E.; Kitajima, H.; Yu, G.Z.; Rüeger, S.; Speidel, L.; Kim, Y.J.; et al. Multi-ancestry genetic study of type 2 diabetes highlights the power of diverse populations for discovery and translation. Nat. Genet. 2022, 54, 560–572. [Google Scholar] [CrossRef]
  380. Vujkovic, M.; Keaton, J.M.; Lynch, J.A.; Miller, D.R.; Zhou, J.; Tcheandjieu, C.; Huffman, J.E.; Assimes, T.L.; Lorenz, K.; Zhu, X.; et al. Discovery of 318 new risk loci for type 2 diabetes and related vascular outcomes among 1.4 million participants in a multi-ancestry meta-analysis. Nat. Genet. 2020, 52, 680–691. [Google Scholar] [CrossRef]
  381. Wang, Z.; Zhu, Q.; Liu, Y.; Chen, S.; Zhang, Y.; Ma, Q.; Chen, X.; Liu, C.; Lei, H.; Chen, H.; et al. Genome-wide association study of metabolites in patients with coronary artery disease identified novel metabolite quantitative trait loci. Clin. Transl. Med. 2021, 11, e290. [Google Scholar] [CrossRef]
  382. Schlosser, P.; Li, Y.; Sekula, P.; Raffler, J.; Grundner-Culemann, F.; Pietzner, M.; Cheng, Y.; Wuttke, M.; Steinbrenner, I.; Schultheiss, U.T.; et al. Genetic studies of urinary metabolites illuminate mechanisms of detoxification and excretion in humans. Nat. Genet. 2020, 52, 167–176. [Google Scholar] [CrossRef]
  383. Li, Y.; Sekula, P.; Wuttke, M.; Wahrheit, J.; Hausknecht, B.; Schultheiss, U.T.; Gronwald, W.; Schlosser, P.; Tucci, S.; Ekici, A.B.; et al. Genome-Wide Association Studies of Metabolites in Patients with CKD Identify Multiple Loci and Illuminate Tubular Transport Mechanisms. J. Am. Soc. Nephrol. 2018, 29, 1513–1524. [Google Scholar] [CrossRef]
  384. Rhee, E.P.; Surapaneni, A.; Zheng, Z.; Zhou, L.; Dutta, D.; Arking, D.E.; Zhang, J.; Duong, T.V.; Chatterjee, N.; Luo, S.; et al. Trans-ethnic genome-wide association study of blood metabolites in the Chronic Renal Insufficiency Cohort (CRIC) study. Kidney Int. 2022, 101, 814–823. [Google Scholar] [CrossRef]
  385. Merritt, J.L.; Norris, M.; Kanungo, S. Fatty acid oxidation disorders. Ann. Transl. Med. 2018, 6, 181–183. [Google Scholar] [CrossRef]
  386. Guerra, I.M.S.; Ferreira, H.B.; Melo, T.; Rocha, H.; Moreira, S.; Diogo, L.; Domingues, M.R.; Moreira, A.S.P. Mitochondrial Fatty Acid β-Oxidation Disorders: From Disease to Lipidomic Studies-A Critical Review. Int. J. Mol. Sci. 2022, 23, 13933. [Google Scholar] [CrossRef]
  387. Gregersen, N.; Winter, V.; Curtis, D.; Deufel, T.; Mack, M.; Hendrickx, J.; Willems, P.J.; Ponzone, A.; Parrella, T.; Ponzone, R.; et al. Medium-chain acyl-CoA dehydrogenase (MCAD) deficiency: The prevalent mutation G985 (K304E) is subject to a strong founder effect from northwestern Europe. Hum. Hered. 1993, 43, 342–350. [Google Scholar] [CrossRef]
  388. Morris, A.A.M. Disorders of mitochondrial fatty acid oxidation and related metabolic pathways. In Inborn Metabolic Diseases: Diagnosis and Treatment; Springer: Berlin/Heidelberg, Germany, 2012; pp. 201–216. ISBN 9783642157202. [Google Scholar]
  389. Nennstiel-Ratzel, U.; Arenz, S.; Maier, E.M.; Knerr, I.; Baumkötter, J.; Röschinger, W.; Liebl, B.; Hadorn, H.B.; Roscher, A.A.; Von Kries, R. Reduced incidence of severe metabolic crisis or death in children with medium chain acyl-CoA dehydrogenase deficiency homozygous for c.985A>G identified by neonatal screening. Mol. Genet. Metab. 2005, 85, 157–159. [Google Scholar] [CrossRef]
  390. Matsubara, Y.; Narisawa, K.; Ye-Qi, Y.; Tada, K.; Ikeda, H.; Danks, D.M.; Green, A.; McCabe, E.R.B. Prevalence of K329E mutation in medium-chain acyl-CoA dehydrogenase gene determined from Guthrie cards. Lancet 1991, 338, 552–553. [Google Scholar] [CrossRef]
  391. Von Muhlendahl, K.E.; Lehnert, W.; Monch, E. Medium-Chain-Acyl-CoA-Dehydrogenase(MCAD)-Defekt: Akute zerebrale Episoden und nicht-ketotische Hypoglykämien bei Kindern. DMW Dtsch. Medizinische Wochenschrift 1990, 115, 1235–1238. [Google Scholar] [CrossRef]
  392. Nagao, M. Frequency of 985A-to-G mutation in medium-chain acyl-CoA dehydrogenase gene among patients with sudden infant death syndrome, Reye syndrome, severe motor and intellectual disabilities and healthy newborns in Japan. Pediatr. Int. 1996, 38, 304–307. [Google Scholar] [CrossRef]
  393. Tyni, T.; Palotie, A.; Viinikka, L.; Valanne, L.; Salo, M.K.; Von Dobeln, U.; Jackson, S.; Wanders, R.; Venizelos, N.; Pihko, H. Long-chain 3-hydroxyacyl-coenzyme A dehydrogenase deficiency with the G1528C mutation: Clinical presentation of thirteen patients. J. Pediatr. 1997, 130, 67–76. [Google Scholar] [CrossRef]
  394. Ijlst, L.; Ruiter, J.P.N.; Hoovers, J.M.N.; Jakobs, M.E.; Wanders, R.J.A. Common missense mutation G1528C in long-chain 3-hydroxyacyl-CoA dehydrogenase deficiency: Characterization and expression of the mutant protein, mutation analysis on genomic DNA and chromosomal localization of the mitochondrial trifunctional protein α sub. J. Clin. Investig. 1996, 98, 1028–1033. [Google Scholar] [CrossRef]
  395. Jankowski, M.; Daca-Roszak, P.; Obracht-Prondzyński, C.; Płoski, R.; Lipska-Ziętkiewicz, B.S.; Ziętkiewicz, E. Genetic diversity in Kashubs: The regional increase in the frequency of several disease-causing variants. J. Appl. Genet. 2022, 63, 691–701. [Google Scholar] [CrossRef]
  396. Spiekerkoetter, U.; Lindner, M.; Santer, R.; Grotzke, M.; Baumgartner, M.R.; Boehles, H.; Das, A.; Haase, C.; Hennermann, J.B.; Karall, D.; et al. Treatment recommendations in long-chain fatty acid oxidation defects: Consensus from a workshop. J. Inherit. Metab. Dis. 2009, 32, 498–505. [Google Scholar] [CrossRef]
  397. Wilcken, B. Fatty acid oxidation disorders: Outcome and long-term prognosis. J. Inherit. Metab. Dis. 2010, 33, 501–506. [Google Scholar] [CrossRef]
  398. Sperk, A.; Mueller, M.; Spiekerkoetter, U. Outcome in six patients with mitochondrial trifunctional protein disorders identified by newborn screening. Mol. Genet. Metab. 2010, 101, 205–207. [Google Scholar] [CrossRef]
  399. Karall, D.; Brunner-Krainz, M.; Kogelnig, K.; Konstantopoulou, V.; Maier, E.M.; Möslinger, D.; Plecko, B.; Sperl, W.; Volkmar, B.; Scholl-Bürgi, S. Clinical outcome, biochemical and therapeutic follow-up in 14 Austrian patients with Long-Chain 3-Hydroxy Acyl CoA Dehydrogenase Deficiency (LCHADD). Orphanet J. Rare Dis. 2015, 10, 1–11. [Google Scholar] [CrossRef]
  400. Kobayashi, T.; Minami, S.; Mitani, A.; Tanizaki, Y.; Booka, M.; Okutani, T.; Yamaguchi, S.; Ino, K. Acute fatty liver of pregnancy associated with fetal mitochondrial trifunctional protein deficiency. J. Obstet. Gynaecol. Res. 2015, 41, 799–802. [Google Scholar] [CrossRef]
  401. Brown, N.F.; Mullur, R.S.; Subramanian, I.; Esser, V.; Bennett, M.J.; Saudubray, J.M.; Feigenbaum, A.S.; Kobari, J.A.; Macleod, P.M.; McGarry, J.D.; et al. Molecular characterization of L-CPT I deficiency in six patients: Insights into function of the native enzyme. J. Lipid Res. 2001, 42, 1134–1142. [Google Scholar] [CrossRef]
  402. Gobin, S.; Bonnefont, J.P.; Prip-Buus, C.; Mugnier, C.; Ferrec, M.; Demaugre, F.; Saudubray, J.M.; Rostane, H.; Djouadi, F.; Wilcox, W.; et al. Organization of the human liver carnitine palmitoyltransferase 1 gene (CPT1A) and identification of novel mutations inn hyketotic hypoglycaemia. Hum. Genet. 2002, 111, 179–189. [Google Scholar] [CrossRef]
  403. Clemente, F.J.; Cardona, A.; Inchley, C.E.; Peter, B.M.; Jacobs, G.; Pagani, L.; Lawson, D.J.; Antão, T.; Vicente, M.; Mitt, M.; et al. A selective sweep on a deleterious mutation in CPT1A in Arctic populations. Am. J. Hum. Genet. 2014, 95, 584–589. [Google Scholar] [CrossRef]
  404. Collins, S.A.; Sinclair, G.; McIntosh, S.; Bamforth, F.; Thompson, R.; Sobol, I.; Osborne, G.; Corriveau, A.; Santos, M.; Hanley, B.; et al. Carnitine palmitoyltransferase 1A (CPT1A) P479L prevalence in live newborns in Yukon, Northwest Territories, and Nunavut. Mol. Genet. Metab. 2010, 101, 200–204. [Google Scholar] [CrossRef]
  405. Rinaldi, C.; Schmidt, T.; Situ, A.J.; Johnson, J.O.; Lee, P.R.; Chen, K.L.; Bott, L.C.; Fadó, R.; Harmison, G.H.; Parodi, S.; et al. Mutation in CPT1C associated with pure autosomal dominant spastic paraplegia. JAMA Neurol. 2015, 72, 561–570. [Google Scholar] [CrossRef]
  406. Hong, D.; Cong, L.; Zhong, S.; Liu, L.; Xu, Y.; Zhang, J. A novel CPT1C variant causes pure hereditary spastic paraplegia with benign clinical course. Ann. Clin. Transl. Neurol. 2019, 6, 610–614. [Google Scholar] [CrossRef]
  407. Boemer, F.; Deberg, M.; Schoos, R.; Caberg, J.H.; Gaillez, S.; Dugauquier, C.; Delbecque, K.; François, A.; Maton, P.; Demonceau, N.; et al. Diagnostic pitfall in antenatal manifestations of CPT II deficiency. Clin. Genet. 2016, 89, 193–197. [Google Scholar] [CrossRef]
  408. Anichini, A.; Fanin, M.; Vianey-Saban, C.; Cassandrini, D.; Fiorillo, C.; Bruno, C.; Angelini, C. Genotype—Phenotype correlations in a large series of patients with muscle type CPT II deficiency. Neurol. Res. 2011, 33, 24–32. [Google Scholar] [CrossRef]
  409. Ørngreen, M.C.; Dunø, M.; Ejstrup, R.; Christensen, E.; Schwartz, M.; Sacchetti, M.; Vissing, J. Fuel utilization in subjects with-carnitine palmitoyltransferase 2 gene mutations. Ann. Neurol. 2005, 57, 60–66. [Google Scholar] [CrossRef]
  410. Mak, C.M.; Lam, C.W.; Fong, N.C.; Siu, W.K.; Lee, H.C.H.; Siu, T.S.; Lai, C.K.; Law, C.Y.; Tong, S.F.; Poon, W.T.; et al. Fatal viral infection-associated encephalopathy in two Chinese boys: A genetically determined risk factor of thermolabile carnitine palmitoyltransferase II variants. J. Hum. Genet. 2011, 56, 617–621. [Google Scholar] [CrossRef]
  411. Kubota, M.; Chida, J.; Hoshino, H.; Ozawa, H.; Koide, A.; Kashii, H.; Koyama, A.; Mizuno, Y.; Hoshino, A.; Yamaguchi, M.; et al. Thermolabile CPT II variants and low blood ATP levels are closely related to severity of acute encephalopathy in Japanese children. Brain Dev. 2012, 34, 20–27. [Google Scholar] [CrossRef]
  412. Gallant, N.M.; Leydiker, K.; Tang, H.; Feuchtbaum, L.; Lorey, F.; Puckett, R.; Deignan, J.L.; Neidich, J.; Dorrani, N.; Chang, E.; et al. Biochemical, molecular, and clinical characteristics of children with short chain acyl-CoA dehydrogenase deficiency detected by newborn screening in California. Mol. Genet. Metab. 2012, 106, 55–61. [Google Scholar] [CrossRef]
  413. Pedersen, C.B.; Kølvraa, S.; Kølvraa, A.; Stenbroen, V.; Kjeldsen, M.; Ensenauer, R.; Tein, I.; Matern, D.; Rinaldo, P.; Vianey-Saban, C.; et al. The ACADS gene variation spectrum in 114 patients with short-chain acyl-CoA dehydrogenase (SCAD) deficiency is dominated by missense variations leading to protein misfolding at the cellular level. Hum. Genet. 2008, 124, 43–56. [Google Scholar] [CrossRef]
  414. Van Maldegem, B.T.; Duran, M.; Wanders, R.J.A.; Niezen-Koning, K.E.; Hogeveen, M.; Ijlst, L.; Waterham, H.R.; Wijburg, F.A. Clinical, Biochemical, and Genetic Heterogeneity in Short-Chain Acyl-Coenzyme A Dehydrogenase Deficiency. JAMA 2006, 296, 943–952. [Google Scholar] [CrossRef]
  415. Strauss, A.W.; Powell, C.K.; Hale, D.E.; Anderson, M.M.; Ahuja, A.; Brackett, J.C.; Sims, H.F. Molecular basis of human mitochondrial very-long-chain acyl-CoA dehydrogenase deficiency causing cardiomyopathy and sudden death in childhood. Proc. Natl. Acad. Sci. USA 1995, 92, 10496–10500. [Google Scholar] [CrossRef]
  416. Yamaguchi, S.; Indo, Y.; Coates, P.M.; Hashimoto, T.; Tanaka, K. Identification of very-long-chain acyl-CoA dehydrogenase deficiency in three patients previously diagnosed with long-chain acyl-CoA dehydrogenase deficiency. Pediatr. Res. 1993, 34, 111–113. [Google Scholar] [CrossRef]
  417. Rinaldo, P.; Matern, D.; Bennett, M.J. Fatty acid oxidation disorders. Annu. Rev. Physiol. 2002, 64, 477–502. [Google Scholar] [CrossRef] [PubMed]
  418. Miller, M.J.; Burrage, L.C.; Gibson, J.B.; Strenk, M.E.; Lose, E.J.; Bick, D.P.; Elsea, S.H.; Sutton, V.R.; Sun, Q.; Graham, B.H.; et al. Recurrent ACADVL molecular findings in individuals with a positive newborn screen for very long chain acyl-coA dehydrogenase (VLCAD) deficiency in the United States. Mol. Genet. Metab. 2015, 116, 139–145. [Google Scholar] [CrossRef]
  419. Burgin, H.J.; Murayama, K.; Ohtake, A.; McKenzie, M. Mitochondrial Short-Chain Enoyl-CoA Hydratase 1 Deficiency (ECHS1D). In Genetic Syndromes; Adam, M.P., Ardinger, H.H., Pagon, R.A., Wallace, S.E., Bean, L.J.H., Mirzaa, G., Amemiya, A., Eds.; Springer International Publishing: Cham, Switzerland, 2022; pp. 1–5. [Google Scholar]
  420. Uesugi, M.; Mori, J.; Fukuhara, S.; Fujii, N.; Omae, T.; Sasai, H.; Ichimoto, K.; Murayama, K.; Osamura, T.; Hosoi, H. Short-chain enoyl-CoA hydratase deficiency causes prominent ketoacidosis with normal plasma lactate levels: A case report. Mol. Genet. Metab. Rep. 2020, 25, 100672. [Google Scholar] [CrossRef]
  421. Huffnagel, I.C.; Redeker, E.J.W.; Reneman, L.; Vaz, F.M.; Ferdinandusse, S.; Poll-The, B.T. Mitochondrial encephalopathy and transient 3-methylglutaconic aciduria in ECHS1 deficiency: Long-term follow-up. JIMD Rep. 2018, 39, 83–87. [Google Scholar] [PubMed]
  422. Fitzsimons, P.E.; Alston, C.L.; Bonnen, P.E.; Hughes, J.; Crushell, E.; Geraghty, M.T.; Tetreault, M.; O’Reilly, P.; Twomey, E.; Sheikh, Y.; et al. Clinical, biochemical, and genetic features of four patients with short-chain enoyl-CoA hydratase (ECHS1) deficiency. Am. J. Med. Genet. Part A 2018, 176, 1115–1127. [Google Scholar] [CrossRef]
  423. Peters, H.; Buck, N.; Wanders, R.; Ruiter, J.; Waterham, H.; Koster, J.; Yaplito-Lee, J.; Ferdinandusse, S.; Pitt, J. ECHS1 mutations in Leigh disease: A new inborn error of metabolism affecting valine metabolism. Brain 2014, 137, 2903–2908. [Google Scholar] [CrossRef]
  424. Sakai, C.; Yamaguchi, S.; Sasaki, M.; Miyamoto, Y.; Matsushima, Y.; Goto, Y. ichi ECHS1 mutations cause combined respiratory chain deficiency resulting in leigh syndrome. Hum. Mutat. 2015, 36, 232–239. [Google Scholar] [CrossRef]
  425. Sun, D.; Liu, Z.; Liu, Y.; Wu, M.; Fang, F.; Deng, X.; Liu, Z.; Song, L.; Murayama, K.; Zhang, C.; et al. Novel ECHS1 mutations in Leigh syndrome identified by whole-exome sequencing in five Chinese families: Case report. BMC Med. Genet. 2020, 21, 149. [Google Scholar] [CrossRef] [PubMed]
  426. Ganetzky, R.D.; Bloom, K.; Ahrens-Nicklas, R.; Edmondson, A.; Deardorff, M.A.; Bennett, M.J.; Ficicioglu, C. ECHS1 deficiency as a cause of severe neonatal lactic acidosis. JIMD Rep. 2016, 30, 33–37. [Google Scholar] [PubMed]
  427. Haack, T.B.; Jackson, C.B.; Murayama, K.; Kremer, L.S.; Schaller, A.; Kotzaeridou, U.; de Vries, M.C.; Schottmann, G.; Santra, S.; Büchner, B.; et al. Deficiency of ECHS1 causes mitochondrial encephalopathy with cardiac involvement. Ann. Clin. Transl. Neurol. 2015, 2, 492–509. [Google Scholar] [CrossRef]
  428. Olgiati, S.; Skorvanek, M.; Quadri, M.; Minneboo, M.; Graafland, J.; Breedveld, G.J.; Bonte, R.; Ozgur, Z.; van den Hout, M.C.G.N.; Schoonderwoerd, K.; et al. Paroxysmal exercise-induced dystonia within the phenotypic spectrum of ECHS1 deficiency. Mov. Disord. 2016, 31, 1041–1048. [Google Scholar] [CrossRef] [PubMed]
  429. Balasubramaniam, S.; Riley, L.G.; Bratkovic, D.; Ketteridge, D.; Manton, N.; Cowley, M.J.; Gayevskiy, V.; Roscioli, T.; Mohamed, M.; Gardeitchik, T.; et al. Unique presentation of cutis laxa with Leigh-like syndrome due to ECHS1 deficiency. J. Inherit. Metab. Dis. 2017, 40, 745–747. [Google Scholar] [CrossRef] [PubMed]
  430. Klootwijk, E.D.; Reichold, M.; Helip-Wooley, A.; Tolaymat, A.; Broeker, C.; Robinette, S.L.; Reinders, J.; Peindl, D.; Renner, K.; Eberhart, K.; et al. Mistargeting of Peroxisomal EHHADH and Inherited Renal Fanconi’s Syndrome. N. Engl. J. Med. 2014, 370, 129–138. [Google Scholar] [CrossRef]
  431. Tolaymat, A.; Sakarcan, A.; Neiberger, R. Idiopathic Fanconi syndrome in a family. Part I. Clinical aspects. J. Am. Soc. Nephrol. 1992, 2, 1310–1317. [Google Scholar] [CrossRef]
  432. Kaufmann, W.E.; Theda, C.; Naidu, S.; Watkins, P.A.; Moser, A.B.; Moser, H.W. Neuronal migration abnormality in peroxisomal bifunctional enzyme defect. Ann. Neurol. 1996, 39, 268–271. [Google Scholar] [CrossRef]
  433. Fukuda, S.; Suzuki, Y.; Shimozawa, N.; Zhang, Z.; Orii, T.; Aoyama, T.; Hashimoto, T.; Kondo, N. Amino acid and nucleotide sequences of human peroxisomal enoyl-CoA hydratase: 3-hydroxyacyl-CoA dehydrogenase cDNA. J. Inherit. Metab. Dis. 1998, 21, 23–28. [Google Scholar] [CrossRef]
  434. Yang, S.Y.; He, X.Y.; Schulz, H. 3-Hydroxyacyl-CoA dehydrogenase and short chain 3-hydroxyacyl-CoA dehydrogenase in human health and disease. FEBS J. 2005, 272, 4874–4883. [Google Scholar] [CrossRef]
  435. Treacy, E.P.; Lambert, D.M.; Barnes, R.; Boriack, R.L.; Vockley, J.; O’Brien, L.K.; Jones, P.M.; Bennett, M.J. Short-chain hydroxyacyl-coenzyme A dehydrogenase deficiency presenting as unexpected infant death: A family study. J. Pediatr. 2000, 137, 257–259. [Google Scholar] [CrossRef] [PubMed]
  436. Bennett, M.J.; Weinberger, M.J.; Kobori, J.A.; Rinaldo, P.; Burlina, A.B. Mitochondrial Short-Chain L-3-Hydroxyacl-Coenzyme A Dehydrogenase Deficiency: A New Defect of Fatty Acid Oxidation. Pediatr. Res. 1996, 39, 185–188. [Google Scholar] [CrossRef]
  437. Bennett, M.J.; Spotswood, S.D.; Ross, K.F.; Comfort, S.; Koonce, R.; Boriack, R.L.; Ijlst, L.; Wanders, R.J.A. Fatal hepatic short-chain 1-3-hydroxyacyl-coenzyme dehydrogenase deficiency: Clinical, biochemical, and pathological studies on three subjects with this recently identified disorder of mitochondrial β-oxidation. Pediatr. Dev. Pathol. 1999, 2, 337–345. [Google Scholar] [CrossRef] [PubMed]
  438. Flanagan, S.E.; Xie, W.; Caswell, R.; Damhuis, A.; Vianey-Saban, C.; Akcay, T.; Darendeliler, F.; Bas, F.; Guven, A.; Siklar, Z.; et al. Next-generation sequencing reveals deep intronic cryptic ABCC8 and HADH splicing founder mutations causing hyperinsulinism by pseudoexon activation. Am. J. Hum. Genet. 2013, 92, 131–136. [Google Scholar] [CrossRef]
  439. Flanagan, S.E.; Patch, A.M.; Locke, J.M.; Akcay, T.; Simsek, E.; Alaei, M.; Yekta, Z.; Desai, M.; Kapoor, R.R.; Hussain, K.; et al. Genome-wide homozygosity analysis reveals HADH mutations as a common cause of diazoxide-responsive hyperinsulinemic-hypoglycemia in consanguineous pedigrees. J. Clin. Endocrinol. Metab. 2011, 96, 96. [Google Scholar] [CrossRef]
  440. Di Candia, S.; Gessi, A.; Pepe, G.; Valin, P.S.; Mangano, E.; Chiumello, G.; Gianolli, L.; Proverbio, M.C.; Mora, S. Identification of a diffuse form of hyperinsulinemic hypoglycemia by 18-fluoro-L-3, 4 dihydroxyphenylalanine positron emission tomography/CT in a patient carrying a novel mutation of the HADH gene. Eur. J. Endocrinol. 2009, 160, 1019–1023. [Google Scholar] [CrossRef] [PubMed]
  441. Arora, C.; Padmanabha, H.; Christopher, R.; Mahale, R.; Bhat, M.; Arunachal, G.; Shekhar, R.; Mailankody, P.; Mathuranath, P.S. Pseudo-neonatal Adrenoleukodystrophy: A Rare Peroxisomal Disorder. Ann. Indian Acad. Neurol. 2022, 25, 275–278. [Google Scholar] [CrossRef]
  442. Aubourg, P.; Wanders, R. Peroxisomal disorders. Handb. Clin. Neurol. 2013, 113, 1593–1609. [Google Scholar] [CrossRef]
  443. Kemp, S.; Valianpour, F.; Mooyer, P.A.W.; Kulik, W.; Wanders, R.J.A. Method for measurement of peroxisomal very-long-chain fatty acid beta-oxidation in human skin fibroblasts using stable-isotope-labeled tetracosanoic acid. Clin. Chem. 2004, 50, 1824–1826. [Google Scholar] [CrossRef]
  444. Bezman, L.; Moser, H.W. Incidence of X-linked adrenoleukodystrophy and the relative frequency of its phenotypes. Am. J. Med. Genet. 1998, 76, 415–419. [Google Scholar] [CrossRef]
  445. Mosser, J.; Douar, A.M.; Sarde, C.O.; Kioschis, P.; Feil, R.; Moser, H.; Poustka, A.M.; Mandel, J.L.; Aubourg, P. Putative X-linked adrenoleukodystrophy gene shares unexpected homology with ABC transporters. Nature 1993, 361, 726–730. [Google Scholar] [CrossRef]
  446. Engelen, M.; Kemp, S.; De Visser, M.; Van Geel, B.M.; Wanders, R.J.A.; Aubourg, P.; Poll-The, B.T. X-linked adrenoleukodystrophy (X-ALD): Clinical presentation and guidelines for diagnosis, follow-up and management. Orphanet J. Rare Dis. 2012, 7, 51. [Google Scholar] [CrossRef]
  447. Kemp, S.; Theodoulou, F.L.; Wanders, R.J.A. Mammalian peroxisomal ABC transporters: From endogenous substrates to pathology and clinical significance. Br. J. Pharmacol. 2011, 164, 1753–1766. [Google Scholar] [CrossRef]
  448. Pugliese, A.; Beltramo, T.; Torre, D. Reye’s and Reye’s-like syndromes. Cell Biochem. Funct. 2008, 26, 741–746. [Google Scholar] [CrossRef]
  449. Schrör, K. Aspirin and Reye syndrome: A review of the evidence. Pediatr. Drugs 2007, 9, 195–204. [Google Scholar] [CrossRef]
  450. Chen, J.; Spracklen, C.N.; Marenne, G.; Varshney, A.; Corbin, L.J.; Luan, J.; Willems, S.M.; Wu, Y.; Zhang, X.; Horikoshi, M.; et al. The Trans-Ancestral Genomic Architecture of Glycemic Traits. Nat. Genet. 2021, 53, 840. [Google Scholar] [CrossRef] [PubMed]
  451. Xue, A.; Wu, Y.; Zhu, Z.; Zhang, F.; Kemper, K.E.; Zheng, Z.; Yengo, L.; Lloyd-Jones, L.R.; Sidorenko, J.; Wu, Y.; et al. Genome-wide association analyses identify 143 risk variants and putative regulatory mechanisms for type 2 diabetes. Nat. Commun. 2018, 9, 2941. [Google Scholar] [CrossRef] [PubMed]
  452. Smith, J.G.; Lowe, J.K.; Kovvali, S.; Maller, J.B.; Salit, J.; Daly, M.J.; Stoffel, M.; Altshuler, D.M.; Friedman, J.M.; Breslow, J.L.; et al. Genome-wide association study of electrocardiographic conduction measures in an isolated founder population: Kosrae. Hear. Rhythm 2009, 6, 634–641. [Google Scholar] [CrossRef]
  453. Vuckovic, D.; Bao, E.L.; Akbari, P.; Lareau, C.A.; Mousas, A.; Jiang, T.; Chen, M.H.; Raffield, L.M.; Tardaguila, M.; Huffman, J.E.; et al. The Polygenic and Monogenic Basis of Blood Traits and Diseases. Cell 2020, 182, 1214–1231. [Google Scholar] [CrossRef] [PubMed]
  454. van Rheenen, W.; van der Spek, R.A.A.; Bakker, M.K.; van Vugt, J.J.F.A.; Hop, P.J.; Zwamborn, R.A.J.; de Klein, N.; Westra, H.J.; Bakker, O.B.; Deelen, P.; et al. Common and rare variant association analyses in amyotrophic lateral sclerosis identify 15 risk loci with distinct genetic architectures and neuron-specific biology. Nat. Genet. 2021, 53, 1636–1648. [Google Scholar] [CrossRef] [PubMed]
  455. Lee, S.B.; Choi, J.E.; Park, B.; Cha, M.Y.; Hong, K.W.; Jung, D.H. Dyslipidaemia—Genotype Interactions with Nutrient Intake and Cerebro-Cardiovascular Disease. Biomedicines 2022, 10, 1615. [Google Scholar] [CrossRef] [PubMed]
  456. Sinnott-Armstrong, N.; Tanigawa, Y.; Amar, D.; Mars, N.; Benner, C.; Aguirre, M.; Venkataraman, G.R.; Wainberg, M.; Ollila, H.M.; Kiiskinen, T.; et al. Genetics of 35 blood and urine biomarkers in the UK Biobank. Nat. Genet. 2021, 53, 185–194. [Google Scholar] [CrossRef]
  457. Astle, W.J.; Elding, H.; Jiang, T.; Allen, D.; Ruklisa, D.; Mann, A.L.; Mead, D.; Bouman, H.; Riveros-Mckay, F.; Kostadima, M.A.; et al. The Allelic Landscape of Human Blood Cell Trait Variation and Links to Common Complex Disease. Cell 2016, 167, 1415–1429.e19. [Google Scholar] [CrossRef]
  458. Graham, S.E.; Clarke, S.L.; Wu, K.H.H.; Kanoni, S.; Zajac, G.J.M.; Ramdas, S.; Surakka, I.; Ntalla, I.; Vedantam, S.; Winkler, T.W.; et al. The power of genetic diversity in genome-wide association studies of lipids. Nature 2021, 600, 675–679. [Google Scholar] [CrossRef]
  459. Morris, A.P.; Le, T.H.; Wu, H.; Akbarov, A.; van der Most, P.J.; Hemani, G.; Smith, G.D.; Mahajan, A.; Gaulton, K.J.; Nadkarni, G.N.; et al. Trans-ethnic kidney function association study reveals putative causal genes and effects on kidney-specific disease aetiologies. Nat. Commun. 2019, 10, 29. [Google Scholar] [CrossRef]
  460. Yin, X.; Chan, L.S.; Bose, D.; Jackson, A.U.; VandeHaar, P.; Locke, A.E.; Fuchsberger, C.; Stringham, H.M.; Welch, R.; Yu, K.; et al. Genome-wide association studies of metabolites in Finnish men identify disease-relevant loci. Nat. Commun. 2022, 13, 19. [Google Scholar] [CrossRef]
  461. Hysi, P.G.; Mangino, M.; Christofidou, P.; Falchi, M.; Karoly, E.D.; Mohney, R.P.; Valdes, A.M.; Spector, T.D.; Menni, C. Metabolome Genome-Wide Association Study Identifies 74 Novel Genomic Regions Influencing Plasma Metabolites Levels. Metabolites 2022, 12, 61. [Google Scholar] [CrossRef] [PubMed]
  462. Shin, S.Y.; Fauman, E.B.; Petersen, A.K.; Krumsiek, J.; Santos, R.; Huang, J.; Arnold, M.; Erte, I.; Forgetta, V.; Yang, T.P.; et al. An atlas of genetic influences on human blood metabolites. Nat. Genet. 2014, 46, 543–550. [Google Scholar] [CrossRef]
  463. Sakaue, S.; Kanai, M.; Tanigawa, Y.; Karjalainen, J.; Kurki, M.; Koshiba, S.; Narita, A.; Konuma, T.; Yamamoto, K.; Akiyama, M.; et al. A cross-population atlas of genetic associations for 220 human phenotypes. Nat. Genet. 2021, 53, 1415–1424. [Google Scholar] [CrossRef]
  464. Feofanova, E.V.; Chen, H.; Dai, Y.; Jia, P.; Grove, M.L.; Morrison, A.C.; Qi, Q.; Daviglus, M.; Cai, J.; North, K.E.; et al. A Genome-wide Association Study Discovers 46 Loci of the Human Metabolome in the Hispanic Community Health Study/Study of Latinos. Am. J. Hum. Genet. 2020, 107, 849–863. [Google Scholar] [CrossRef] [PubMed]
  465. Yu, B.; Zheng, Y.; Alexander, D.; Morrison, A.C.; Coresh, J.; Boerwinkle, E. Genetic Determinants Influencing Human Serum Metabolome among African Americans. PLoS Genet. 2014, 10, e1004212. [Google Scholar] [CrossRef]
  466. Liu, H.; Doke, T.; Guo, D.; Sheng, X.; Ma, Z.; Park, J.; Vy, H.M.T.; Nadkarni, G.N.; Abedini, A.; Miao, Z.; et al. Epigenomic and transcriptomic analyses define core cell types, genes and targetable mechanisms for kidney disease. Nat. Genet. 2022, 54, 950–962. [Google Scholar] [CrossRef] [PubMed]
  467. Liu, M.; Jiang, Y.; Wedow, R.; Li, Y.; Brazel, D.M.; Chen, F.; Datta, G.; Davila-Velderrain, J.; McGuire, D.; Tian, C.; et al. Association studies of up to 1.2 million individuals yield new insights into the genetic etiology of tobacco and alcohol use. Nat. Genet. 2019, 51, 237–244. [Google Scholar] [CrossRef] [PubMed]
  468. Karlsson Linnér, R.; Biroli, P.; Kong, E.; Meddens, S.F.W.; Wedow, R.; Fontana, M.A.; Lebreton, M.; Tino, S.P.; Abdellaoui, A.; Hammerschlag, A.R.; et al. Genome-wide association analyses of risk tolerance and risky behaviors in over 1 million individuals identify hundreds of loci and shared genetic influences. Nat. Genet. 2019, 51, 245–257. [Google Scholar] [CrossRef] [PubMed]
  469. Emilsson, V.; Ilkov, M.; Lamb, J.R.; Finkel, N.; Gudmundsson, E.F.; Pitts, R.; Hoover, H.; Gudmundsdottir, V.; Horman, S.R.; Aspelund, T.; et al. Co-regulatory networks of human serum proteins link genetics to disease. Science 2018, 361, 769–773. [Google Scholar] [CrossRef]
  470. Thareja, G.; Belkadi, A.; Arnold, M.; Albagha, O.M.E.; Graumann, J.; Schmidt, F.; Grallert, H.; Peters, A.; Gieger, C.; Consortium, T.Q.G.P.R.; et al. Differences and commonalities in the genetic architecture of protein quantitative trait loci in European and Arab populations. Hum. Mol. Genet. 2022, 32, 907–916. [Google Scholar] [CrossRef]
  471. Hernandez Cordero, A.I.; Gonzales, N.M.; Parker, C.C.; Sokolof, G.; Vandenbergh, D.J.; Cheng, R.; Abney, M.; Sko, A.; Douglas, A.; Palmer, A.A.; et al. Genome-wide Associations Reveal Human-Mouse Genetic Convergence and Modifiers of Myogenesis, CPNE1 and STC2. Am. J. Hum. Genet. 2019, 105, 1222–1236. [Google Scholar] [CrossRef]
  472. Richardson, T.G.; Leyden, G.M.; Wang, Q.; Bell, J.A.; Elsworth, B.; Smith, G.D.; Holmes, M.V. Characterising metabolomic signatures of lipid-modifying therapies through drug target mendelian randomisation. PLoS Biol. 2022, 20, e3001547. [Google Scholar] [CrossRef]
  473. Christakoudi, S.; Evangelou, E.; Riboli, E.; Tsilidis, K.K. GWAS of allometric body-shape indices in UK Biobank identifies loci suggesting associations with morphogenesis, organogenesis, adrenal cell renewal and cancer. Sci. Rep. 2021, 11, 10688. [Google Scholar] [CrossRef]
  474. Ritchie, M.D.; Verma, S.S.; Hall, M.A.; Goodloe, R.J.; Berg, R.L.; Carrell, D.S.; Carlson, C.S.; Chen, L.; Crosslin, D.R.; Denny, J.C.; et al. Electronic medical records and genomics (eMERGE) network exploration in cataract: Several new potential susceptibility loci. Mol. Vis. 2014, 20, 1281–1295. [Google Scholar]
  475. Timmins, I.R.; Zaccardi, F.; Nelson, C.P.; Franks, P.; Yates, T.; Dudbridge, F. Genome-wide association study of self-reported walking pace suggests beneficial effects of brisk walking on health and survival. Commun. Biol. 2020, 3, 634. [Google Scholar] [CrossRef] [PubMed]
  476. Evangelou, E.; Gao, H.; Chu, C.; Ntritsos, G.; Blakeley, P.; Butts, A.R.; Pazoki, R.; Suzuki, H.; Koskeridis, F.; Yiorkas, A.M.; et al. New alcohol-related genes suggest shared genetic mechanisms with neuropsychiatric disorders. Nat. Hum. Behav. 2019, 3, 950–961. [Google Scholar] [CrossRef] [PubMed]
  477. Zhou, H.; Sealock, J.M.; Sanchez-Roige, S.; Clarke, T.K.; Levey, D.F.; Cheng, Z.; Li, B.; Polimanti, R.; Kember, R.L.; Smith, R.V.; et al. Genome-wide meta-analysis of problematic alcohol use in 435,563 individuals yields insights into biology and relationships with other traits. Nat. Neurosci. 2020, 23, 809–818. [Google Scholar] [CrossRef] [PubMed]
  478. Saunders, G.R.B.; Wang, X.; Chen, F.; Jang, S.K.; Liu, M.; Wang, C.; Gao, S.; Jiang, Y.; Khunsriraksakul, C.; Otto, J.M.; et al. Genetic diversity fuels gene discovery for tobacco and alcohol use. Nature 2022, 612, 720–724. [Google Scholar] [CrossRef] [PubMed]
  479. Chouraki, V.; De Bruijn, R.F.A.G.; Chapuis, J.; Bis, J.C.; Reitz, C.; Schraen, S.; Ibrahim-Verbaas, C.A.; Grenier-Boley, B.; Delay, C.; Rogers, R.; et al. A genome-wide association meta-analysis of plasma Aβ peptides concentrations in the elderly. Mol. Psychiatry 2014, 19, 1326–1335. [Google Scholar] [CrossRef]
  480. Medina-Gomez, C.; Kemp, J.P.; Trajanoska, K.; Luan, J.; Chesi, A.; Ahluwalia, T.S.; Mook-Kanamori, D.O.; Ham, A.; Hartwig, F.P.; Evans, D.S.; et al. Life-Course Genome-wide Association Study Meta-analysis of Total Body BMD and Assessment of Age-Specific Effects. Am. J. Hum. Genet. 2018, 102, 88–102. [Google Scholar] [CrossRef]
  481. Richardson, T.G.; Sanderson, E.; Palmerid, T.M.; Korpelaid, M.A.; Ference, B.A.; Smith, G.D.; Holmes, M.V. Evaluating the relationship between circulating lipoprotein lipids and apolipoproteins with risk of coronary heart disease: A multivariable Mendelian randomisation analysis. PLoS Med. 2020, 17, e1003062. [Google Scholar] [CrossRef]
  482. Tin, A.; Marten, J.; Halperin Kuhns, V.L.; Li, Y.; Wuttke, M.; Kirsten, H.; Sieber, K.B.; Qiu, C.; Gorski, M.; Yu, Z.; et al. Target genes, variants, tissues and transcriptional pathways influencing human serum urate levels. Nat. Genet. 2019, 51, 1459–1474. [Google Scholar] [CrossRef]
  483. Borges, M.C.; Haycock, P.C.; Zheng, J.; Hemani, G.; Holmes, M.V.; Davey Smith, G.; Hingorani, A.D.; Lawlor, D.A. Role of circulating polyunsaturated fatty acids on cardiovascular diseases risk: Analysis using Mendelian randomization and fatty acid genetic association data from over 114,000 UK Biobank participants. BMC Med. 2022, 20, 210. [Google Scholar] [CrossRef]
  484. Wyss, A.B.; Sofer, T.; Lee, M.K.; Terzikhan, N.; Nguyen, J.N.; Lahousse, L.; Latourelle, J.C.; Smith, A.V.; Bartz, T.M.; Feitosa, M.F.; et al. Multiethnic meta-analysis identifies ancestry-specific and cross-ancestry loci for pulmonary function. Nat. Commun. 2018, 9, 2976. [Google Scholar] [CrossRef]
  485. Chai, J.F.; Raichur, S.; Khor, I.W.; Torta, F.; Chew, W.S.; Herr, D.R.; Ching, J.; Kovalik, J.P.; Khoo, C.M.; Wenk, M.R.; et al. Associations with metabolites in Chinese suggest new metabolic roles in Alzheimer’s and Parkinson’s diseases. Hum. Mol. Genet. 2020, 29, 189–201. [Google Scholar] [CrossRef]
  486. Jia, Q.; Han, Y.; Huang, P.; Woodward, N.C.; Gukasyan, J.; Kettunen, J.; Ala-Korpela, M.; Anufrieva, O.; Wang, Q.; Perola, M.; et al. Genetic Determinants of Circulating Glycine Levels and Risk of Coronary Artery Disease. J. Am. Heart Assoc. 2019, 8. [Google Scholar] [CrossRef]
  487. Lotta, L.A.; Pietzner, M.; Stewart, I.D.; Wittemans, L.B.L.; Li, C.; Bonelli, R.; Raffler, J.; Biggs, E.K.; Oliver-Williams, C.; Auyeung, V.P.W.; et al. Cross-platform genetic discovery of small molecule products of metabolism and application to clinical outcomes. Nat. Genet. 2021, 53, 54. [Google Scholar] [CrossRef]
  488. Wittemans, L.B.L.; Lotta, L.A.; Oliver-Williams, C.; Stewart, I.D.; Surendran, P.; Karthikeyan, S.; Day, F.R.; Koulman, A.; Imamura, F.; Zeng, L.; et al. Assessing the causal association of glycine with risk of cardio-metabolic diseases. Nat. Commun. 2019, 10. [Google Scholar] [CrossRef]
  489. Illig, T.; Gieger, C.; Zhai, G.; Römisch-Margl, W.; Wang-Sattler, R.; Prehn, C.; Altmaier, E.; Kastenmüller, G.; Kato, B.S.; Mewes, H.W.; et al. A genome-wide perspective of genetic variation in human metabolism. Nat. Genet. 2010, 42, 137–141. [Google Scholar] [CrossRef] [PubMed]
  490. Kachuri, L.; Jeon, S.; DeWan, A.T.; Metayer, C.; Ma, X.; Witte, J.S.; Chiang, C.W.K.; Wiemels, J.L.; de Smith, A.J. Genetic determinants of blood-cell traits influence susceptibility to childhood acute lymphoblastic leukemia. Am. J. Hum. Genet. 2021, 108, 1823–1835. [Google Scholar] [CrossRef] [PubMed]
  491. Gouveia, M.H.; Bentley, A.R.; Leonard, H.; Meeks, K.A.C.; Ekoru, K.; Chen, G.; Nalls, M.A.; Simonsick, E.M.; Tarazona-Santos, E.; Lima-Costa, M.F.; et al. Trans-ethnic meta-analysis identifies new loci associated with longitudinal blood pressure traits. Sci. Rep. 2021, 11, 4075. [Google Scholar] [CrossRef] [PubMed]
  492. Hu, Y.; Bien, S.A.; Nishimura, K.K.; Haessler, J.; Hodonsky, C.J.; Baldassari, A.R.; Highland, H.M.; Wang, Z.; Preuss, M.; Sitlani, C.M.; et al. Multi-ethnic genome-wide association analyses of white blood cell and platelet traits in the Population Architecture using Genomics and Epidemiology (PAGE) study. BMC Genom. 2021, 22, 432. [Google Scholar] [CrossRef]
  493. Qayyum, R.; Snively, B.M.; Ziv, E.; Nalls, M.A.; Liu, Y.; Tang, W.; Yanek, L.R.; Lange, L.; Evans, M.K.; Ganesh, S.; et al. A meta-analysis and genome-wide association study of platelet count and mean platelet volume in African Americans. PLoS Genet. 2012, 8, e1002491. [Google Scholar] [CrossRef]
  494. Igarashi, M.; Nogawa, S.; Kawafune, K.; Hachiya, T.; Takahashi, S.; Jia, H.; Saito, K.; Kato, H. Identification of the 12q24 locus associated with fish intake frequency by genome-wide meta-analysis in Japanese populations. Genes Nutr. 2019, 14, 21. [Google Scholar] [CrossRef]
  495. Cho, S.K.; Kim, B.; Myung, W.; Chang, Y.; Ryu, S.; Kim, H.N.; Kim, H.L.; Kuo, P.H.; Winkler, C.A.; Won, H.H. Polygenic analysis of the effect of common and low-frequency genetic variants on serum uric acid levels in Korean individuals. Sci. Rep. 2020, 10, 9179. [Google Scholar] [CrossRef] [PubMed]
  496. Yasukochi, Y.; Sakuma, J.; Takeuchi, I.; Kato, K.; Oguri, M.; Fujimaki, T.; Horibe, H.; Yamada, Y. Identification of CDC42BPG as a novel susceptibility locus for hyperuricemia in a Japanese population. Mol. Genet. Genom. 2018, 293, 371–379. [Google Scholar] [CrossRef] [PubMed]
  497. Yang, W.; Li, L.; Feng, X.; Cheng, H.; Ge, X.; Bao, Y.; Huang, L.; Wang, F.; Liu, C.; Chen, X.; et al. Genome-wide association and Mendelian randomization study of blood copper levels and 213 deep phenotypes in humans. Commun. Biol. 2022, 5, 405. [Google Scholar] [CrossRef] [PubMed]
  498. Gudjonsson, A.; Gudmundsdottir, V.; Axelsson, G.T.; Gudmundsson, E.F.; Jonsson, B.G.; Launer, L.J.; Lamb, J.R.; Jennings, L.L.; Aspelund, T.; Emilsson, V.; et al. A genome-wide association study of serum proteins reveals shared loci with common diseases. Nat. Commun. 2022, 13, 480. [Google Scholar] [CrossRef] [PubMed]
  499. Liu, X.; Xu, H.; Xu, H.; Geng, Q.; Mak, W.H.; Ling, F.; Su, Z.; Yang, F.; Zhang, T.; Chen, J.; et al. New genetic variants associated with major adverse cardiovascular events in patients with acute coronary syndromes and treated with clopidogrel and aspirin. Pharmacogenom. J. 2021, 21, 664–672. [Google Scholar] [CrossRef] [PubMed]
  500. Watanabe, K.; Jansen, P.R.; Savage, J.E.; Nandakumar, P.; Wang, X.; Agee, M.; Aslibekyan, S.; Auton, A.; Bell, R.K.; Bryc, K.; et al. Genome-wide meta-analysis of insomnia prioritizes genes associated with metabolic and psychiatric pathways. Nat. Genet. 2022, 54, 1125–1132. [Google Scholar] [CrossRef]
Figure 2. Metabolism of phytanic acid.
Figure 2. Metabolism of phytanic acid.
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Figure 3. Omega oxidation of very-long-chain fatty acids (VLCFAs).
Figure 3. Omega oxidation of very-long-chain fatty acids (VLCFAs).
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Figure 4. The role of free fatty acids in the acetylation of proteins.
Figure 4. The role of free fatty acids in the acetylation of proteins.
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Figure 5. The role of FAO in cancer cell survival and growth. FFAs—free fatty acids, OAA—oxaloacetic acid, IDH—isocitrate dehydrogenase, ME—malic enzyme.
Figure 5. The role of FAO in cancer cell survival and growth. FFAs—free fatty acids, OAA—oxaloacetic acid, IDH—isocitrate dehydrogenase, ME—malic enzyme.
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Table 1. Characteristics of acyl-CoA synthetases. ACSL—long-chain acyl-CoA synthetase, ACSM—medium-chain acyl-CoA synthetases, ACSS—short-chain acyl-CoA synthetases, ACSVL—very-long-chain acyl-CoA synthetase, BAT—brown adipose tissue, ER—endoplasmic reticulum, WAT—white adipose tissue.
Table 1. Characteristics of acyl-CoA synthetases. ACSL—long-chain acyl-CoA synthetase, ACSM—medium-chain acyl-CoA synthetases, ACSS—short-chain acyl-CoA synthetases, ACSVL—very-long-chain acyl-CoA synthetase, BAT—brown adipose tissue, ER—endoplasmic reticulum, WAT—white adipose tissue.
Name/AbbreviationOrgan/Tissue LocalizationSubcellular CompartmentReferences
ACSVL [FATP2]Liver, intestine, kidneys, brainPeroxisomes, ER[34]
ACSVL [FATP6]HeartCytosol, plasma membrane[35]
ACSVL [FATP3]Lungs, gonads, adrenalsER, mitochondrial membrane[34]
ACSVL [FATP1]Skeletal muscles, BAT, WAT, heartPlasma membrane[36]
ACSVL [FATP4]Skeletal muscles, BAT, WAT, intestine, skinPeroxisomes, ER, mitochondrial membrane[37]
ACSVL [FATP5]LiverPlasma membrane[38]
ACSL1Liver, heart, BAT, WAT, skeletal musclesMitochondria (outer mitochondrial membrane on the cytosolic side), lipid droplets, microsomes, plasma membrane[39]
ACSL3Brain, gonads, small amounts in other tissues (liver)Lipid droplets, the cytoplasmic face of ER, the outer mitochondrial membrane[40]
ACSL4Adrenals, ovaries, testes, liver, skeletal muscles, small amounts in the brainEndosomes, peroxisomes, plasma membrane, secretory vesicles, ER regions in close contact with mitochondria—mitochondrial-associated membranes[41]
ACSL5BAT, the duodenal mucosa, liver, skeletal muscles, kidneys, lungsThe outer mitochondrial membrane on the cytosolic side[42]
ACSL6Ovaries, testes, brain, skeletal muscles, small amounts in the WAT, kidneys, the duodenal mucosaPlasma membrane[43]
ACSMLiver, skeletal muscles, cardiomyocytes, colonocytes, kidneysMitochondria. All ACSMs belong to a group of enzymes called XM-ligases (xenobiotic/medium-chain fatty acid-CoA ligases)[44,45]
ACSS1Brain, blood, testes, intestine, heart, kidneys, skeletal muscles, BATMitochondria. ACSS1 activates acetate[46]
ACSS2Liver and kidneysCytosol, nucleus. ACSS2 activates acetate. ACSS2 is downregulated during fasting[46,47]
ACSS3LiverMitochondria. ACSS3 has a higher affinity for propionate. ACSS3 is upregulated in the fasting state[30,46]
Table 2. Characteristics of acyl-CoA dehydrogenases. ACAD9—acyl-CoA dehydrogenase DH-9, BCFA—branched-chain fatty acid, LCAD—long-chain acyl-CoA dehydrogenase, LCFA—long-chain fatty acid, MCAD—medium-chain acyl-CoA dehydrogenase, MCFA—medium-chain fatty acid, SCAD—short-chain acyl-CoA dehydrogenase, SCFA—short-chain fatty acid, VLCAD—very-long-chain acyl-CoA dehydrogenase, VLCFA—very-long-chain fatty acid.
Table 2. Characteristics of acyl-CoA dehydrogenases. ACAD9—acyl-CoA dehydrogenase DH-9, BCFA—branched-chain fatty acid, LCAD—long-chain acyl-CoA dehydrogenase, LCFA—long-chain fatty acid, MCAD—medium-chain acyl-CoA dehydrogenase, MCFA—medium-chain fatty acid, SCAD—short-chain acyl-CoA dehydrogenase, SCFA—short-chain fatty acid, VLCAD—very-long-chain acyl-CoA dehydrogenase, VLCFA—very-long-chain fatty acid.
EnzymeMitochondrial CompartmentPreferred Substrates (Acyl-CoAs)Tissue/Organ/CellReference
VLCADInner mitochondrial membraneLCFA (mainly palmitoyl-CoA) and VLCFA (C14–C22)Muscles, heart, liver, skin fibroblasts[84]
Acyl-CoA DH-9 (ACAD9)Inner mitochondrial membraneUnsaturated LCFA, VLCFA (C16:1, C18:1, C18:2; C22:6)Brain, liver, heart, skeletal muscle[85]
LCADMatrixLCFA, unsaturated MCFA, SCFA, BCFA (in vitro)Lungs—pulmonary surfactant[86]
MCADMatrixMCFA (C6:0–C12:0)Heart, skeletal muscles, liver[87]
SCADMatrixSCFA (mainly butyryl-CoA);
MCFA (C6:0–C12:0)
Liver, heart, skeletal muscle[88]
Table 3. Comparison between peroxisomal and mitochondrial β-oxidation. ABCD1–4—ATP-binding cassette sub-family D 1–4, ACADs—acyl-CoA dehydrogenases, ACOXs—acyl-CoA oxidases, BCFA—branched-chain fatty acid, CPT1—carnitine palmitoyltransferase 1, CPT2—carnitine palmitoyltransferase 2, CAC—acylcarnitine translocase, FAs—fatty acids, VLCADs—very-long-chain fatty acids, LCFAs—long-chain fatty acids, MCFAs—medium-chain fatty acids, PUFAs—polyunsaturated fatty acids, SCFAs—short-chain fatty acids, H2O—hydrogen peroxide, ETF—electron-transferring flavoprotein, OXPHOS—oxidative phosphorylation.
Table 3. Comparison between peroxisomal and mitochondrial β-oxidation. ABCD1–4—ATP-binding cassette sub-family D 1–4, ACADs—acyl-CoA dehydrogenases, ACOXs—acyl-CoA oxidases, BCFA—branched-chain fatty acid, CPT1—carnitine palmitoyltransferase 1, CPT2—carnitine palmitoyltransferase 2, CAC—acylcarnitine translocase, FAs—fatty acids, VLCADs—very-long-chain fatty acids, LCFAs—long-chain fatty acids, MCFAs—medium-chain fatty acids, PUFAs—polyunsaturated fatty acids, SCFAs—short-chain fatty acids, H2O—hydrogen peroxide, ETF—electron-transferring flavoprotein, OXPHOS—oxidative phosphorylation.
Peroxisomal β-OxidationMitochondrial β-OxidationReferences
Proteins involved in the transport of FAs to peroxisomes/mitochondriaABCD1, ABCD2, and ABCD3Carnitine transport system (CPT1, CPT2, CAC)[115,116]
SubstratesVLCFAs (>C22), BCFAs (e.g., pristanic acid), PUFA, 2-hydroxy FAs, long-chain dicarboxylic acids, bile acid intermediates, and a number of prostanoidsVLCFAs (≤22), LCFAs, MCFAs, and SCFAs[117,118]
Enzyme catalyzing the first reactionACOXs
The transfer of electrons from FADH2 to oxygen results in the production of H2O2, which is subsequently cleaved by peroxisomal catalase
ACADs
The electrons that originate from FADH2 are transported to ETF, the ETF dehydrogenase, and transferred to OXPHOS. Finally, they reduce oxygen to water, which results in the production of energy in the form of ATP
[82,110]
β-oxidation end productsAcetyl-CoA, NADH, MCFAs, and FADH2Acetyl-CoA, NADH, and FADH2[94,110]
Table 4. Changes in FAO enzymes and fatty acid-binding protein gene expression in various cancers. ACAD9—acyl-CoA dehydrogenase DH-9, ACSL4—long-chain acyl CoA synthetase 4, AR—androgen receptor, CPT—carnitine palmitoyl transferase, ECH—enoyl-CoA-hydratase, EHHADH—enoyl-CoA hydratase and 3-hydroxyacyl CoA dehydrogenase, ESR—estrogen receptor, FABP—fatty acid-binding protein, HADH—3-hydroxyacyl-CoA dehydrogenase, HADHA—hydroxyacyl-CoA dehydrogenase/3-ketoacyl-CoA thiolase/enoyl-CoA hydratase (trifunctional protein), alpha subunit, LCAD—long-chain acyl-CoA dehydrogenase, SCAD—short-chain acyl-CoA dehydrogenase.
Table 4. Changes in FAO enzymes and fatty acid-binding protein gene expression in various cancers. ACAD9—acyl-CoA dehydrogenase DH-9, ACSL4—long-chain acyl CoA synthetase 4, AR—androgen receptor, CPT—carnitine palmitoyl transferase, ECH—enoyl-CoA-hydratase, EHHADH—enoyl-CoA hydratase and 3-hydroxyacyl CoA dehydrogenase, ESR—estrogen receptor, FABP—fatty acid-binding protein, HADH—3-hydroxyacyl-CoA dehydrogenase, HADHA—hydroxyacyl-CoA dehydrogenase/3-ketoacyl-CoA thiolase/enoyl-CoA hydratase (trifunctional protein), alpha subunit, LCAD—long-chain acyl-CoA dehydrogenase, SCAD—short-chain acyl-CoA dehydrogenase.
Gene/EnzymeNature of ChangeType of EvaluationCancer TypeReferences
ACAD9UpregulatedmRNA levelGlioblastoma multiforme[289]
ACSL1DownregulatedmRNA levelLung cancer, breast cancer[290,291]
UpregulatedmRNA levelRectal adenocarcinoma, colon cancer, hepatocellular carcinoma[290,292,293,294]
ACSL3DownregulatedmRNA levelOvarian cancer[290]
UpregulatedmRNA levelMelanoma, ESR-negative breast cancer[290,295]
Protein levelLarge-cell lung cancer, small-cell lung cancer[296]
ACSL4DownregulatedmRNA and protein levelsGastric cancer[297]
mRNA levelLung cancer[290]
UpregulatedmRNA levelColorectal cancer, ESR-negative breast cancer, triple-negative breast cancer, AR-negative prostate, hepatocellular carcinoma[290,292,298,299,300,301]
Protein levelProstate cancer[302]
mRNA and protein levelsColon adenocarcinoma, hepatocellular carcinoma[303,304]
ACSL5DownregulatedmRNA levelBreast cancer[290]
mRNA and protein levelsSmall intestine cancer[305]
UpregulatedmRNA levelBladder cancer, colorectal cancer[290,306,307]
ACSL6DownregulatedmRNA levelLeukemia[290]
UpregulatedmRNA levelColorectal cancer[290,308]
CPT1AUpregulatedProtein levelGastric cancer[309]
mRNA levelGlioblastoma multiforme[289]
CPT1BUpregulatedmRNA and protein levelsProstate cancer[310]
mRNA levelHigh-grade bladder cancer[311]
CPT1CUpregulatedmRNA levelGastric cancer, lung cancer, papillary thyroid carcinoma[312,313,314]
CPT2DownregulatedmRNA levelHepatocellular carcinoma, colorectal cancer, ovarian cancer[308,315,316]
UpregulatedmRNA levelGlioblastoma multiforme[289]
ECH1DownregulatedmRNA levelColorectal cancer[317]
EHHADHDownregulatedmRNA and protein levelsHepatocellular carcinoma[318]
UpregulatedmRNA levelOsteosarcoma[319]
FABP3UpregulatedmRNA and protein levelsNon-small-cell lung cancer[320]
FABP4DownregulatedmRNA levelStomach adenocarcinoma[321]
mRNA and protein levelsHepatocellular carcinoma[322]
UpregulatedProtein levelHigh-grade serous ovarian carcinoma, pancreatic ductal adenocarcinoma,
gastric adenocarcinoma
[323,324,325]
mRNA and protein levelsNon-small-cell lung cancer, prostate cancer[320,326]
FABP5UpregulatedProtein levelGastric adenocarcinoma[325]
HADHDownregulatedProtein levelGastric cancer[327]
mRNA levelGastric cancer, kidney renal clear cell carcinoma[328,329,330]
UpregulatedmRNA levelColon cancer, acute myeloid leukemia[331,332]
HADHADownregulatedmRNA levelBreast cancer[333]
LCADDownregulatedmRNA levelHepatocellular carcinoma[334]
MCADUpregulatedProtein levelGlioblastoma, squamous cell carcinoma of the head and neck[335,336]
SCADDownregulatedmRNA levelColorectal cancer[317]
Table 5. Cancer cell FAO as a potential therapeutic target. ACSL—long-chain fatty acid synthetase, ACSVL—very-long-chain fatty acid synthetase, CPT—carnitine palmitoyltransferase, ECHS—enoyl-CoA hydratase short chain 1, MCAD—medium-chain acyl-CoA dehydrogenase, PP2—4-amino-5-(4-chlorophenyl)-7-(t-butyl)pyrazolo[3,4-d]pyrimidine.
Table 5. Cancer cell FAO as a potential therapeutic target. ACSL—long-chain fatty acid synthetase, ACSVL—very-long-chain fatty acid synthetase, CPT—carnitine palmitoyltransferase, ECHS—enoyl-CoA hydratase short chain 1, MCAD—medium-chain acyl-CoA dehydrogenase, PP2—4-amino-5-(4-chlorophenyl)-7-(t-butyl)pyrazolo[3,4-d]pyrimidine.
Targeted EnzymeInhibitor/Interfering CompoundExperimental ModelsEffectsReferences
ACSL4RosiglitazoneBreast cancer cell linesInhibition of cancer cell growth[356]
PRGL493Breast cancer cell lines, prostate cancer cell linesInhibition of cancer cell growth and sensitization to chemotherapy[357]
ACSL5Triacsin CGlioma cell linesInhibition of cancer cell survival[358]
Small interfering RNALung cancer cell linesInhibition of cancer cell growth[359]
ACSVL3Small interfering RNAGlioblastoma cell linesInhibition of cancer cell growth and tumourigenicity[360]
CPT1Avocatin BPrimary myeloid leukemia cellsInhibition of cancer cell survival[361]
EtomoxirLeukemia, breast, prostate, colorectal cancer cell lines, and the xenograft modelInhibition of cancer cell growth, survival, and tumourigenicity[288,362,363,364,365]
Lung cell linesSensitization to radiation[366]
OxfenicineMelanoma cell linesInhibition of cancer cell growth[367]
Small interfering RNAsBrest cancer cell linesInhibition of cancer cell survival[368]
CPT2AminocarnitineGlioma cell linesInhibition of cancer cell growth[369]
PerhexilineGastrointestinal cancer cell linesInhibition of cancer cell survival and sensitization to chemotherapy[370]
ECHS1Small interfering RNA, PP2Breast cancer cell linesInhibition of cancer cell survival[371]
MCADHairpin RNA interferenceGlioblastoma cell linesInhibition of cancer cell survival[335]
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Szrok-Jurga, S.; Czumaj, A.; Turyn, J.; Hebanowska, A.; Swierczynski, J.; Sledzinski, T.; Stelmanska, E. The Physiological and Pathological Role of Acyl-CoA Oxidation. Int. J. Mol. Sci. 2023, 24, 14857. https://doi.org/10.3390/ijms241914857

AMA Style

Szrok-Jurga S, Czumaj A, Turyn J, Hebanowska A, Swierczynski J, Sledzinski T, Stelmanska E. The Physiological and Pathological Role of Acyl-CoA Oxidation. International Journal of Molecular Sciences. 2023; 24(19):14857. https://doi.org/10.3390/ijms241914857

Chicago/Turabian Style

Szrok-Jurga, Sylwia, Aleksandra Czumaj, Jacek Turyn, Areta Hebanowska, Julian Swierczynski, Tomasz Sledzinski, and Ewa Stelmanska. 2023. "The Physiological and Pathological Role of Acyl-CoA Oxidation" International Journal of Molecular Sciences 24, no. 19: 14857. https://doi.org/10.3390/ijms241914857

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