Search Results (249)

Fat deposition plays a key role in determining porcine meat quality traits, with lipid droplets serving as critical organelles for lipid storage in adipose tissue. Inhibiting lipid droplet biogenesis disrupts the lipid storage capacity of adipocytes. The Stearoyl-CoA Desaturase (SCD) family is crucial in regulating polyunsaturated fatty acid/monounsaturated fatty acid (PUFA/MUFA) composition, while its role in lipid droplet formation remains unclear. This study employed CRISPR/Cas9 to create SCD1-deficient porcine renal epithelial cells (PK15), enabling an investigation into SCD1’s role in fatty acid composition and lipid droplet regulation. RNA-seq analysis was conducted to elucidate the mechanisms underlying SCD1’s impact on lipid droplet numbers. Results showed that SCD1 deletion significantly decreased triacylglycerols (TAG) content, altered fatty acid composition, and decreased lipid droplet numbers. Conversely, SCD1 overexpression increased lipid droplet numbers, confirming SCD1’s role in regulating lipid droplet abundance. RNA-seq analysis revealed that SCD1 regulates lipid metabolism via Calsyntenin 3β (CLSTN3B). Experimental validation confirmed the SCD1-CLSTN3B regulation of lipid droplet numbers. In summary, we discovered the role of SCD1 in regulating the number of lipid droplets, highlighting its potential impact on lipid metabolism and adipocyte function in pigs. Full article

Soft tissue reconstruction remains a challenge in clinical practice, particularly for restoring substantial volume loss due to surgical resections or contour deformities. Current methods, such as autologous fat transplantation, have limitations, including donor site morbidity and insufficient tissue availability, necessitating an innovative approach. This study characterizes alloClae, a minimally manipulated human-derived adipose allograft prepared using a detergent-based protocol to reduce DNA content while preserving adipose tissue structure. Proteomic analysis revealed that alloClae retains key native proteins critical for graft integration with the host and stability, with key extracellular matrix (ECM) components, collagens, elastins, and laminin, which are more concentrated as a result of the detergent-based protocol. Biocompatibility of alloClae was assessed in vitro using cytotoxicity and cell viability assays in fibroblast cultures, revealing no adverse effects on cell viability, membrane integrity, or oxidative stress. Additionally, in vitro studies with adipose-derived stem cells (ASCs) demonstrated attachment and differentiation, with lipid droplet accumulation observed by day 14, indicating support for adipogenesis. A 6-month longitudinal study in athymic mice showed stable graft retention, host cell infiltration, and formation of new adipocytes and vasculature within alloClae by 3 months. The findings highlight alloClae’s ability to support host-driven adipogenesis and angiogenesis while maintaining graft stability throughout the study period. It presents a promising alternative to the existing graft materials, offering a clinically translatable solution for soft tissue reconstruction. Full article

The protozoan parasite Toxoplasma gondii transitions between acute (tachyzoite) and chronic (bradyzoite) stages, enabling lifelong persistence in hosts. Iron depletion triggers bradyzoite differentiation, with the phosphotyrosyl phosphatase activator (PTPA) identified as a key regulator. Here, we define PTPA’s role in T. gondii pathogenesis. PTPA forms a ternary complex with PP2A A/C subunits, validated by reciprocal pull-down assays. Depleting PTPA impaired tachyzoite proliferation, invasion, and gliding motility, while stress-induced bradyzoites exhibited defective cyst formation and vacuolar swelling. Metabolic dysregulation included amylopectin accumulation and lipid droplet proliferation. The PP2A inhibitor LB-100 phenocopied PTPA depletion, suppressing tachyzoite growth and bradyzoite differentiation. TgPTPA emerges as a linchpin coordinating PP2A activity, metabolic flux, and lifecycle transitions. Its dual roles in acute virulence and chronic persistence, combined with LB-100’s efficacy, position the PTPA–PP2A axis as a promising target for antitoxoplasmosis strategies. Full article

Background/Objectives: Disruptions in adipose tissue dynamics contribute to obesity-related metabolic disorders, emphasizing the need for targeted therapies focusing on adipose tissue cells, including progenitor cells and adipocytes. Peroxisome proliferator-activated receptor gamma (PPARG) ligands are potent insulin sensitizers used in type 2 diabetes treatment. This study investigated the effects of rosiglitazone, a PPARG agonist, and betulinic acid, a PPARG antagonist, on adipogenesis and apoptosis in 3T3-L1 pre-adipocytes. Method: 3T3-L1 pre-adipocytes were treated with rosiglitazone or betulinic acid during adipogenic differentiation. Lipid droplet formation was used to evaluate adipogenesis. Cell growth and cell death were assessed using the resazurin-based cell viability assay, trypan blue exclusion assay, LDH assay, and Annexin V/PI staining. Quantitative PCR was conducted to examine the expression of genes associated with adipogenesis and apoptosis. Results: Betulinic acid reduced adipogenesis only when administered daily for eight days. Rosiglitazone did not alter the overall lipid quantity; however, it promoted a shift toward fewer but larger lipid droplets. Both compounds increased Adipoq and Cfd expression, and betulinic acid also elevated Fabp4. Rosiglitazone induced stronger cell aggregation. Despite increased cell death, overall viability was maintained. Apoptotic cell death was enhanced by both compounds and confirmed via Annexin V/PI staining and flow cytometry, accompanied by downregulation of Ccnd1 and Bcl2. Additionally, rosiglitazone markedly increased the expression of Cebpa, a key regulator that can modulate lipid droplet formation and the balance between cell growth and death. Conclusions: Rosiglitazone and betulinic acid differentially modulate adipogenesis and apoptosis in 3T3-L1 cells, revealing a complex interplay between lipid accumulation and programmed cell death. Together, the findings underscore the potential of dual PPARG-targeting approaches for metabolic disease interventions. Full article

Background: Fat embolism and fat embolism syndrome are rare but well-known consequences of long bone fractures and orthopedic surgeries. These sources support the mechanical theory of their development. On the other hand, as an alternative pathway suggested by the biochemical theory, lipase activation and fat breakdown are also a possible background for lipid droplets appearing in the vasculature. According to Hulman’s theory, elevated C-reactive protein levels can facilitate calcium-dependent agglutination of very low-density proteins and chylomicrons forming fat globules. The level of this acute-phase protein can increase mainly in advanced-stage cancers but also has predictive or indicative value in treatment success. Methods: This study focused on strictly selected patients with different histological types and origins of cancer, as well as advanced cancer in approximately 90% of the deceased. After collecting the tissue samples, the frozen sections were stained with Oil Red O to detect fat emboli. Results: Less than 50% of the cases showed punctiform, non-clinically relevant pulmonary fat embolism, and fat embolism syndrome was identified in none of the cases. In one, non-advanced cancer case, punctiform kidney fat embolism was observed. Conclusions: The end-of-life anergic state of patients may influence the procedure. In the case of osseous metastases, since the intramedullary sinuses are affected, both the mechanical and the biochemical backgrounds may prevail and mediate fat embolism formation. Full article

Recent studies have demonstrated that dietary plant extracts can inhibit the development of lipid droplets (LDs) and oxidized LDs (oxLDs) in hepatic cells. These findings suggest that such extracts may be beneficial in combating metabolic dysfunction-associated fatty liver disease (MAFLD) and its more advanced stage, metabolic dysfunction-associated steatohepatitis (MASH). We examined nine Allium extracts (ALs: AL1–9) to assess their capacity to decrease lipid droplet accumulation (LDA) and oxidative stress by suppressing lipid formation and oxidation in liver cells. Among the Allium extracts tested, AL6 exhibited significant inhibitory effects against LDA. Furthermore, we employed our lipidomic method to assess the accumulation and suppression of intracellular triacylglycerol (TAG) and oxidized TAG hydroperoxide [TG (OOH) n = 3] by AL6 in liver cells under oleic acid (OA) and linoleic acid (LA) loading conditions. These findings indicate that foods derived from Allium species prevent the formation of lipid droplets by decreasing intracellular lipids and lipid hydroperoxides in the hepatocytes. Analysis of the metabolome of bioactive lipid droplet accumulation inhibition (LDAI) AL6 using LC-MS/MS and 1D-NMR [¹H, ¹³C, DEPT 90, and 135] techniques revealed that AL6 is primarily composed of carbohydrates, glucosidic metabolites, and organosulfur compounds, with small amounts of polyols, fatty acyls, small peptides, and amino acids. This implies that AL6 could be a valuable resource for developing functional foods and drug discovery targeting metabolic dysfunction-associated fatty liver disease (MAFLD)/metabolic dysfunction-associated steatohepatitis (MASH) and related disorders. Full article

A covalent complex of okra seed protein (OSP) and rutin was prepared using the alkali-induced method and characterized. Its application in nanoemulsions was also evaluated. Multi-spectral analysis confirmed the formation of the covalent complex, with OSP as the main body. With an increasing rutin dosage during the preparation process, the amount of rutin in the complex progressively ascended, and the α-helix structure and surface hydrophobicity of the complex gradually declined. The complex exhibited remarkable ABTS radical scavenging capacity and reducing power, which were proportional to the total phenolic content. The OSP/rutin complex could be utilized for the fabrication of O/W nanoemulsions, which remained stable in terms of droplet size and appearance after 28 days of storage at both 4 °C and 25 °C. Furthermore, lipid oxidation in the nanoemulsion stabilized by the OSP/rutin covalent complex could be effectively inhibited, and the emulsion could enhance the UV irradiation resistance of lutein loaded in the oil phase. Our results can provide a reference for the development of protein–polyphenol covalent complexes. Full article

The circadian clock, an intrinsic 24 h cellular timekeeping system, regulates fundamental biological processes, including tumor physiology and metabolism. Cancer stem cells (CSCs), a subpopulation of cancer cells with self-renewal and tumorigenic capacities, are implicated in tumor initiation, recurrence, and metastasis. Despite growing evidence for the circadian clock’s involvement in regulating CSC functions, its precise regulatory mechanisms remain largely unknown. Here, using a human osteosarcoma (OS) model (143B), we have shown that core molecular clock factors are critical for OS stem cell survival and behavior via direct modulation of CSC and lipid metabolic pathways. In single-cell-derived spheroid formation assays, 143B OS cells exhibited robust spheroid-forming capacity under 3D culture conditions. Furthermore, siRNA-mediated depletion of core clock components (i.e., BMAL1, CLOCK, CRY1/2, PER1/2)—essential positive and negative elements of the circadian clock feedback loop—significantly reduced spheroid formation in 143B CSCs isolated from in vivo OS xenografts. In contrast, knockdown of the secondary clock-stabilizing factor genes NR1D1 and NR1D2 had little effect. We also found that knockdown of BMAL1, CLOCK, or CRY1/2 markedly impaired the migration and invasion capacities of 143B CSCs. At the molecular level, silencing of BMAL1, CLOCK, or CRY1/2 distinctly altered the expression of genes associated with stem cell properties and the epithelial–mesenchymal transition (EMT) in 143B CSCs. In addition, disruption of BMAL1, CLOCK, or CRY1/2 expression significantly reduced lipid droplet formation by downregulating the expression of genes involved in lipogenesis (e.g., DGAT1, FASN, ACSL4, PKM2, CHKA, SREBP1), which are closely linked to CSC/EMT processes. Furthermore, transcriptomic analysis of human OS patient samples revealed that compared with other core clock genes, CRY1 was highly expressed in OS tumors relative to controls, and its expression exhibited strong positive correlations with patient prognosis, survival, and LD biogenesis gene expression. These findings highlight the critical role of the molecular circadian clock in regulating CSC properties and metabolism, underscoring the therapeutic potential of targeting the core clock machinery to enhance OS treatment outcomes. Full article

Mastitis, a prevalent inflammatory disease in mammals, disrupts mammary gland function, compromises milk quality, and can contribute to increased offspring morbidity and mortality. Maintaining the health of porcine mammary epithelial cells (PMECs), the primary cell type in the mammary gland, is crucial for minimizing the adverse effects of this disease. Selenium yeast (SeY), an organic selenium compound known for its antioxidant and immune-enhancing properties, has yet to be fully understood in its role in modulating inflammation in mammary gland. In this study, lipopolysaccharide (LPS) (50 µg/mL, 24 h) significantly upregulated the expression of pro-inflammatory cytokines, including tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), interleukin-8 (IL-8), and interleukin-1β (IL-1β) (p < 0.05). Pretreatment with 1 µM SeY significantly attenuated the LPS-induced inflammatory response by reducing the levels of TNF-α, IL-6, IL-8, and IL-1β (p < 0.05). Additionally, SeY enhanced cellular antioxidant defenses by increasing total antioxidant capacity (T-AOC), superoxide dismutase (SOD) activity, glutathione (GSH) levels, and glutathione peroxidase (GSH-Px) activity, while concurrently decreasing malondialdehyde (MDA) accumulation (p < 0.05). SeY also restored both intracellular and extracellular triglyceride levels and rescued lipid droplet formation, which were disrupted by LPS treatment. Furthermore, SeY upregulated key regulators involved in milk synthesis (p < 0.05). These findings suggest that SeY effectively mitigates LPS-induced inflammation and oxidative stress while preserving critical pathways for milk fat and protein synthesis in PMECs. Full article

Triple-negative breast cancer (TNBC) presents limited therapeutic options and is characterized by a poor prognosis. Although Kinsenoside (KIN) possesses a wide range of pharmacological activities, its effect and mechanism in TNBC remain unclear. The objective of this research was to explore the therapeutic effectiveness and the molecular mechanisms of KIN on TNBC. Xenograft experiment was carried out to assess the impact of KIN on TNBC in vivo. The effect of KIN on TNBC in vitro was evaluated through the analysis of cell cytotoxicity and colony formation assays. Oil Red O staining and BODIPY 493/503 fluorescence staining were employed to detect the effect of KIN on lipid droplet (LD) formation. Transcriptomics and inhibitor-rescue experiments were conducted to investigate the role of KIN on TNBC. Mechanistic experiments, including quantitative real-time polymerase chain reaction (RT-qPCR), Western blotting, diacylglycerol acyltransferase 1 (DGAT1) overexpression assay, and flow cytometric assay, were employed to uncover the regulatory mechanisms of KIN on TNBC. KIN inhibited tumor growth without causing obvious toxicity to the liver and kidneys. In vitro experiments demonstrated that KIN significantly inhibited the viability and proliferation of TNBC cells, accompanied by decreased LD formation and lipid content. Polyunsaturated fatty acids (PUFAs) levels were significantly increased by KIN. Furthermore, transcriptomics and inhibitor-rescue experiments revealed that KIN induced ferroptosis in TNBC cells. KIN could significantly regulate ferroptosis-related proteins. Lipid peroxidation, iron accumulation, and GSH depletion also confirmed this. The LD inducer mitigated the KIN-induced ferroptosis in TNBC. The overexpression of DGAT1 attenuated the effects of KIN on cell viability and proliferation. Furthermore, the overexpression of DGAT1 inhibited the effect of KIN to trigger ferroptosis in TNBC cells. Our findings confirmed that KIN could trigger ferroptosis by suppressing DGAT1-mediated LD formation, thereby demonstrating a promising therapeutic effect of KIN in TNBC. Full article

Lead (Pb) is one of the most common environmental pollutants that negatively impacts male reproductive health. Thus far, the underlying molecular mechanisms of Pb-induced reproductive toxicity are still not well understood. In this study, 64 male ICR mice were given drinking water with Pb (0, 100, 200, and 300 mg/L) for 90 days. We found that exposure to 300 mg/L Pb resulted in reduced sperm quality and elevated autophagy-related protein levels in the mouse testes. Our findings indicate that the Pb hindered the autophagic clearance by impairing the lysosomes’ function and then obstructing the fusion of lysosomes and autophagosomes. The autophagy cycle obstruction prevented the lipid droplets from breakdown and led to their accumulation in the Sertoli cells. In turn, the ccytotoxic effects that resulted from the interruption of the autophagy maturation stage, instead of the elongation phase, could be alleviated by either Chloroquine or Bafilomycin A1. Furthermore, exposure to 400 μM Pb initiated the TFE3 nuclear translocation and caused the increased expression of its target genes. Then, the knockdown of TFE3 reduced the formation of the autophagosome. In addition, the use of the antioxidant NAC notably enhanced the autophagic activity and reduced the occurrence of lipid droplets in the Sertoli cells. This study demonstrated that Pb disrupted the autophagic flow, which caused lipid droplet accumulation in the TM4 cells. Consequently, focusing on the maturation stage of autophagy might offer a potential therapeutic approach to alleviate male reproductive toxicity caused by Pb exposure. Full article

Phosphatidylcholine cytidine transferase α (CCTα) is a key rate-limiting enzyme in the CDP–choline pathway, the primary pathway for phosphatidylcholine (PC) synthesis in mammals. This study investigated the role of CCTα in lipid droplet (LD) formation, phospholipid synthesis, LD fusion, and lipophagy in bovine mammary epithelial cells (BMECs) through CCTα gene knockout (CCT-KO) and overexpression (CCT-OE). CCTα mRNA expression was significantly increased in bovine mammary gland tissue after lactation. In BMECs, CCTα was transferred from the nucleus to the endoplasmic reticulum and localized on LD surfaces in the presence of linoleic acid. Compared with normal BMECs (NC), CCTα knockout (CCT-KO) cells had significantly greater LD diameters (1.53 μm vs. 1.68 μm, p < 0.05), lower proportions of small LDs (<1 µm; 11.39% vs. 5.42%), and higher proportions of large LDs (>3 µm; 0.67% vs. 2.88%). In contrast, CCTα overexpression (CCT-OE) decreased the diameter of LDs to 1.18 μm (p < 0.01), increased the proportion of small LDs to 35.48%, and decreased the proportion of large LDs to 0.24%. CCTα knockout significantly decreased the PC content and the ratio of PC to PE, whereas CCTα overexpression increased the PC content and the ratio of PC to phosphatidyl ethanolamine (PE) (p < 0.05). The lipidomics analysis indicated that PC synthesis was significantly influenced by CCTα gene expression. Live cell observations showed that CCTα knockout promoted the fusion of small LDs into large LDs. In cells with CCT α overexpression, the expression of the microtubule-associated protein 1 light chain 3 (LC3) protein and the number of lysosomes was elevated, and the lysosomal phagocytosis of LDs was observed through transmission electron microscopy, thus indicating that CCTα overexpression enhanced lipophagy. In conclusion, these results suggest that CCTα plays a role in regulating LD formation by influencing PC synthesis, LD fusion, and lipophagy in BMECs. Full article

Peruvian maca (Lepidium meyenii) is a plant known for its nutritional and medicinal properties whose use as a supplement in animal diets has attracted much interest. We studied the effects of powdered maca root extract on the growth potential of in vitro cultured porcine cells prior to its use as an additive in animal nutrition. Fibroblast cell viability (MTT), cell proliferation (BrdU), and apoptosis level (TUNEL) were measured for a range of extract doses (0, 0.5, 1.0, 2.0, 3.0, 4.0, 5.0, 7.0, and 10 mg/mL). Transcript levels of CCND1, MCM2, and PCNA genes as molecular markers of cell proliferation were also determined. Next, the effects of maca extract at 2 and 5 mg/mL on in vitro induced adipogenesis were evaluated over eight days of differentiation. The transcript levels of three adipocyte marker genes (CEBPA, PPARG, and FABPB4) were measured at days 0, 4, and 8 of adipose differentiation, and lipid droplet accumulation (BODIPY staining) was also noted. No cytotoxic effect was detected on fibroblast cell viability, and the inhibitory concentration (IC₅₀) value was determined to be IC₅₀ > 10 mg/mL. Doses of maca extract above 3 mg/mL decreased cell proliferation. The transcript level decreased in concentrations above 5 for the MCM2 and PCNA genes. For the CCND1 gene, the transcript level decreased when the greatest maca dose was used. In the in vitro adipogenesis experiment, it was found that the rate of lipid droplet formation increased on day 4 of differentiation for both doses, while decreased lipid droplet formation was observed on day 8 for 5 mg/mL of maca extract. Significant changes were seen in the mRNA level for CEBPA and PPARG on days 4 and 8, while the transcript of FABP4 increased only on day 8 at 2 mg/mL dose. It can be concluded that the addition of Peruvian maca in small doses (<3 mg/mL) has no negative effect on porcine fibroblast growth or proliferation, while 2 mg/mL of maca extract enhances adipocyte differentiation. Full article

Porcine Reproductive and Respiratory Syndrome (PRRS) is a contagious disease that impacts swine health worldwide. Lipid metabolism plays a vital role in energy production and is regulated by various genes involved in lipogenesis and lipolysis. In this study, we found that PRRSV infection significantly reduced the protein expression of STEAP3. The overexpression of STEAP3 can notably inhibit PRRSV replication. Additionally, we utilized transcriptomics and metabolomics to examine the effects of STEAP3 on PRRSV replication, identifying important pathways associated with energy metabolism and lipogenesis. We subsequently found that STEAP3 can suppress PRRSV replication by regulating fatty acid synthesis and enhancing lipid droplet formation. Overall, these findings indicate that STEAP3 could be a potential target for developing strategies to manage PRRSV infection by modulating lipid metabolism. Full article

Background: Hepatic fibrosis (HF) is a progressive liver disease characterized by the activation of hepatic stellate cells (HSCs) and changes in lipid metabolism. Abnormal ketone body (KD) levels, including acetoacetate (AcAc) and beta-hydroxybutyrate (BHB), have been observed in patients with HF, but the mechanisms linking ketone metabolism to fibrosis progression remain unclear. Objectives: This study aimed to investigate the role of AcAc in modulating HSCs activation and its potential mechanisms in HF. Methods: We examined the effects of AcAc on HSCs activation by Western blot analysis and RT-PCR both in vivo and in vitro. The impact of AcAc on lipid droplet accumulation in HSCs was assessed using total cholesterol (TC), triglyceride (TG), and Retinol (RET) kits, along with Nile Red and Oil Red O staining. RT-PCR screening was performed to analyze the expression of genes involved in lipid droplet formation and lipid metabolism. Results: Our findings show that AcAc inhibited HSCs activation by restoring LD levels. Peroxisome Proliferator-Activated Receptor Gamma (PPARγ) was identified as a key regulator through gene screening. AcAc primarily regulated PPARγ expression, and knocking down PPARγ significantly aggravated HF progression. Conclusions: The ability of AcAc to restore LD levels and regulate PPARγ suggests that it may represent a promising therapeutic strategy for HF by inhibiting HSCs activation. Full article