Search Results (471)

Ochratoxin A (OTA), a toxic compound generated by Aspergillus and Penicillium fungi, is a common contaminant in different food and animal feed sources, thereby posing possible dangers to human well-being. Although OTA is widely recognized for its kidney-damaging properties, new findings have also indicated its potential to harm the nervous system. Current research trends have increasingly examined the part played by environmental poisons, such as mycotoxins, in the development of diseases. This systematic review gathers and assesses the features of OTA along with the insights acquired from studies on its neurotoxicity. This work presents recent research that demonstrates some mechanisms by which OTA crosses the intestinal and blood–brain barriers, penetrating neural structures. In addition, it discusses the effect of OTA on several types of neural cells and its roles in apoptosis, neuroinflammation, and neurogenesis defects, while also determining the effects of antioxidant systems that neutralize the effects of OTA. This paper identifies crucial gaps in the research and highlights the necessity for further in-depth studies into how OTA affects the processes underlying neurodegeneration. Filling these knowledge gaps could provide valuable insights into the neurotoxic potential of OTA and its relevance to neurological disorders. Full article

Background/Objectives: High-altitude environments have a significant detrimental impact on the cognitive functions of the brain. Qi Jing Wan (QJW), a traditional herbal formula composed of Angelica sinensis, Astragalus membranaceus, and Rhizoma Polygonati Odorati, has demonstrated potential efficacy in treating cognitive disorders. However, its effects on cognitive dysfunction in plateau hypoxic environments remain unclear. Methods: In this study, acute and chronic plateau cognitive impairment mouse models were constructed to investigate the preventive and therapeutic effects of QJW and its significant active ingredient, diosgenin (Dio). Behavioral experiments were conducted to assess learning and memory in mice. Morphological changes in hippocampal neurons and synapses were assessed, and microglial activation and inflammatory factor levels were measured to evaluate brain damage. Potential active ingredients capable of crossing the blood–brain barrier were identified through chemical composition analysis and network database screening, followed by validation in animal and brain organoid experiments. Transcriptomics analysis, immunofluorescence staining, and molecular docking techniques were employed to explore the underlying mechanisms. Results: QJW significantly enhanced learning and memory abilities in plateau model mice, reduced structural damage to hippocampal neurons, restored NeuN expression, inhibited inflammatory factor levels and microglial activation, and improved hippocampal synaptic damage. Transcriptomics analysis revealed that Dio alleviated hypoxic brain damage and protected cognitive function by regulating the expression of PDE4C. Conclusions: These findings indicate that QJW and its significant active ingredient Dio effectively mitigate hypoxic brain injury and prevent cognitive impairment in high-altitude environments. Full article

Retinoic acid (RA), a vitamin A derivative, has been shown to prevent the development of neurological disorders by ensuring the integrity of the physiological structure of the neurovascular unit and regulating the physiological cell’s function. After an ischemia event, RA reduces the effects of blood–brain barrier disruption by blocking the apoptotic signaling pathway. However, the effect of RA on smooth muscle cells (SMCs), which are crucial to maintaining blood perfusion, has never been investigated. This study aimed to evaluate the effect of RA on the vasoactive response of middle cerebral artery SMCs in normal and ischemic contexts (O₂ and glucose deprivation, OGD). For this purpose, SMCs cultures were incubated with RA, and the vasoactive response was evaluated in both conditions (OGD and non-OGD). To simulate OGD, co-cultures of neurons and astrocytes were made and incubated with RA to analyze the effect of the secretome released by these cells on SMCs contractility. In non-OGD conditions, RA induced rapid relaxation of SMCs and, in the long term (24 h), promoted cell contraction. In OGD conditions, SMCs contractility patterns were different when pre-incubated with RA. In these conditions, NA loses its contractility effect, and SNP seems to revert its relaxant effect. However, SMCs pre-incubated with 5 uM RA show the vasorelaxant pattern typical of SNP, despite the OGD condition. These effects demonstrate an effect of RA on the vasoactive profile of SMCs, with therapeutic potential in OGD conditions. Full article

Intrinsically disordered proteins (IDPs), such as tau, beta-amyloid (Aβ), and alpha-synuclein (αSyn), are prone to misfolding, resulting in pathological aggregation and propagation that drive neurodegenerative diseases, including Alzheimer’s disease (AD), frontotemporal dementia (FTD), and Parkinson’s disease (PD). Misfolded IDPs are prone to aggregate into oligomers and fibrils, exacerbating disease progression by disrupting cellular functions in the central nervous system, triggering neuroinflammation and neurodegeneration. Furthermore, aggregated IDPs exhibit prion-like behavior, acting as seeds that are released into the extracellular space, taken up by neighboring cells, and have a propagating pathology across different regions of the brain. Conventional inhibitors, such as small molecules, peptides, and antibodies, face challenges in stability and blood–brain barrier penetration, limiting their efficacy. In recent years, nanotechnology-based strategies, such as multifunctional nanoplatforms or nanoparticles, have emerged as promising tools to address these challenges. These nanoplatforms leverage tailored designs to prevent or remodel the aggregation of IDPs and reduce associated neurotoxicity. This review discusses recent advances in nanoplatforms designed to target tau, Aβ, and αSyn aggregation, with a focus on their roles in reducing neuroinflammation and neurodegeneration. We examine critical aspects of nanoplatform design, including the choice of material backbone and targeting moieties, which influence interactions with IDPs. We also highlight key mechanisms including the interaction between nanoplatforms and IDPs to inhibit their aggregation, redirect aggregation cascade towards nontoxic, off-pathway species, and disrupt fibrillar structures into soluble forms. We further outline future directions for enhancing IDP clearance, achieving spatiotemporal control, and improving cell-specific targeting. These nanomedicine strategies offer compelling paths forward for developing more effective and targeted therapies for neurodegenerative diseases. Full article

In this study, we synthesized a novel trimethoprim derivative, 4-(((2-amino-5-(3,4,5-trimethoxybenzyl) pyrimidine-4-yl)imino)methyl)benzene-1,3-diol (HD), by the reaction of trimethoprim with 2,4-dihydroxybenzaldehyde. We then prepared metal complexes of this derivative with Cu(II), Co(II), Ni(II), Ag(I), and Zn(II) and functionalized them with ZnO and Au nanoparticles. Their structures were confirmed through ¹H NMR, mass spectrometry, FTIR, conductivity, thermal analysis, magnetic susceptibility, X-ray diffraction, UV-Vis spectroscopy, and TEM, revealing octahedral geometries for all complexes. Surface features were investigated using density functional theory (DFT) analysis. Pharmacokinetic parameters and target enzymes for HD and its complexes were computed using the SwissADME web tool, with the BOILED-Egg model indicating that HD and its Cu complex should be passively permeable via the blood-brain barrier and highly absorbed by the gastrointestinal tract (GIT), unlike the Ni, Co, Ag, and Zn complexes, which are predicted to show low GIT absorption. Molecular docking studies with the Caspase-3 enzyme (PDB code: 3GJQ) using the AutoDock 4.2 software demonstrated binding energies of −7.66, −8.36, −9.05, −8.62, −6.90, and −7.81 kcal/mol for HD and the Cu, Co, Ni, Ag, and Zn complexes, respectively, compared to −6.54 and −4.63 kcal/mol for TMP and 5-FU (5-fluorouracil), indicating a potential superior anticancer potential of the novel compounds. The anticancer activities of these complexes were evaluated using the MTT assay. The IC₅₀ values for 5-FU, TMP, HD, Cu-HD, HD@ZnONPs, Cu-HD@ZnONPs, HD@AuNPs, and Cu-HD@AuNPs were found to be 32.53, 80.76, 114.7, 61.66, 77, 53.13, 55.06, and 50.81 µg/mL, respectively. Notably, all derivatives exhibited higher activity against the HepG-2 cancer cell line than TMP, except for HD, which showed similar effectiveness to TMP. Real-time PCR analysis revealed that the Au-HD@AuNPs and Cu-HD@AuNPs significantly increased caspase-3 inhibition by 4.35- and 4.5-fold and P53 expression by 3.05- and 3.41-fold, respectively, indicating enhanced pro-apoptotic gene expression and apoptosis induction in HepG2 cells. Our findings demonstrate that these novel derivatives possess significant anticancer properties, with some complexes showing superior activity compared to standard drugs such as 5-Fluorouracil (5-FU) and Trimethoprim (TMP). This study highlights the potential of these nanocomposites as promising candidates for cancer therapy. Full article

Curcumin, a polyphenolic compound derived from Curcuma longa, has gained significant attention for its potential therapeutic benefits, particularly counteracting inflammation, oxidative stress, and metabolic disorders. Its chemical structure, featuring conjugated double bonds between two aromatic rings, allows it to act as an electron donor, thereby mitigating free radical formation. Despite its poor solubility in water, curcumin is stable in acidic environments and undergoes significant metabolism in both the liver and the gut. Intestinal microbiota, particularly at the colon level, further metabolizes curcumin into several derivatives, including dihydrocurcumin and tetrahydrocurcumin, which exhibit antioxidant and anti-inflammatory properties. Studies suggest that curcumin can reduce body mass index (BMI) and improve other body composition parameters, especially when used in combination with lifestyle changes, though its bioavailability is low due to its rapid metabolism and the resulting low blood concentration. In obesity, dysfunctional adipose tissue remodeling and chronic inflammation play critical roles in the development of metabolic complications. Curcumin’s anti-inflammatory properties are related to the inhibition of the NF-κB pathway, leading to the reduction in inflammatory markers in adipocytes and macrophages. Additionally, curcumin modulates oxidative stress by activating the NRF2 pathway, enhancing cellular antioxidant defenses. Emerging evidence also supports curcumin’s potential in improving gut health by modulating microbiota composition, enhancing intestinal barrier function, and reducing systemic inflammation. This interaction with the gut–brain axis highlights the broader implications of curcumin in neuroprotection, as it positively affects cognitive function and mitigates neuroinflammation in neurodegenerative diseases like Alzheimer’s. disease. Thus, curcumin holds promise as a multifaceted agent in the management of obesity and associated diseases. Full article

Background: Quinoline-derived metabolites exhibit notable chemical complexity. What causes minor structural alterations to induce significant changes in disease outcomes? Historically, eclipsed by more straightforward scaffolds, these chemicals serve as a dynamic hub in tryptophan metabolism, linking immunomodulation, excitotoxicity, and cancer. However, many of these compounds struggle to cross the blood–brain barrier, and we still do not fully understand how certain structural changes affect their bioavailability or off-target effects. Thus, contemporary research highlights halogenation, esterification, and computational modeling to enhance structure–activity relationships. Summary: This narrative review emphasizes the integration of rational drug design, multi-target ligands, and prodrug methods in enhancing quinoline scaffolds. We explore each molecule’s therapeutic promise, refine each scaffold’s design, and develop each derivative to maximize clinical utility. Translating these laboratory findings into clinical practice, however, remains a formidable challenge. Conclusions: Through the synthesis of findings regarding NMDA receptor antagonism, improved oral bioavailability, and reduced metabolic instability, we demonstrate how single-site changes might modulate excitotoxicity and immunological signaling. Advancing quinoline-based medicines will yield significant advancements in neurology, psychiatry, and oncology. This enlarged framework fosters collaborative discovery, engages various audiences, and advances the field towards next-generation disease-modifying therapies. Robust preclinical validation, patient classification, and comprehensive toxicity evaluations are crucial stages for achieving these extensive endeavors and fostering future therapeutic discoveries globally. Full article

Understanding the timing of fetal brain vulnerability to inflammatory changes in pregnancy complications is crucial for predicting neurodevelopmental risks. Beyond the placenta, the developing brain’s vascular system is believed to form a secondary defense, the blood–brain barrier (BBB), which restricts harmful substances that could disrupt neurodevelopment. However, the precise timing and mechanisms underlying BBB development are poorly understood. In this study, we examined the spatiotemporal expression of key BBB components and fetal brain vascularization in mice from gestational days (GD) 10 to 18. Fetal brain sections were immunostained to identify BBB components, including CD31, Factor VIII, NG2, and claudin-5. Our results showed that endothelial precursor cells form the primitive vascular network in a caudal-to-rostral gradient by GD10, with pericyte recruitment stabilizing vessels by GD12 in a lateral-to-medial gradient that aligns with neurogenesis, despite some regional exceptions. However, Factor VIII was not detected until GD15, and claudin-5 until GD18, suggesting a significant delay in endothelial maturation and tight junction formation. These findings highlight the critical timing of structural developments in the fetal brain vasculature and its vulnerability to placental diseases, laying the groundwork for future research on the impact of placental disorders on fetal brain development and potential therapeutic interventions. Full article

The BBB is created by a special system of brain microvascular endothelial cells (BMECs), pericytes (PCs), the capillary basement membrane, and the terminal branches (“end-feet”) of astrocytes (ACs). The key function of the BBB is to protect the central nervous system (CNS) from potentially harmful/toxic substances in the bloodstream by selectively controlling the entry of cells and molecules, including nutrients and components of the immune system. The loss of BBB integrity in response to neuroinflammation, as manifested by an increase in permeability, depends predominantly on the activity of proinflammatory cytokines. However, the pathomechanism of structural and functional changes in the BBB under the influence of individual cytokines is still poorly understood. This review summarizes the current state of knowledge on this topic, which is important from both pathophysiological and therapeutic points of view. The structures and functions of all components of the BBB are reviewed, with emphasis given to differences between this and other locations of the circulatory system. The protein composition of the interendothelial tight junctions in the context of regulating BBB permeability is presented, as is the role of pericyte–BMEC interactions in the exchange of metabolites, ions, and nucleic acids. Finally, the documented actions of proinflammatory cytokines within the BBB are discussed. Full article

Objective: To evaluate the efficacy of the neurotropic action of cortexin in models of mental and physical developmental delays in rat offspring. Methods: The neurotropic properties of bovine brain cortex polypeptides were studied using two models of mental and physical developmental delays in rats: toxic CNS damage (oral administration of ethanol during the last week of pregnancy) and neonatal trauma (ischemia-hypoxia). The drug was administered intramuscularly or rectally as suppositories for 20 days. Treatment efficacy was evaluated using the mNSS scale, open field, rotarod, and adhesive removal tests. A histological examination of the brain was subsequently performed. In a separate series of experiments in mice, the concentration of the test drug cortexin and the reference drug cerebrolysin was determined in blood and brain tissue samples using radioactive iodine (Na125I) labeling of these preparations. Results: Modeling developmental delay in rat offspring (due to the toxic effect of ethanol in late pregnancy or neonatal trauma) led to pronounced neurological deficits, manifested by decreased motor activity, and sensorimotor, and coordination disorders. Administration of cortexin in all forms reduced the severity of neurological deficits as measured by mNSS scores, improved motor activity in the Open Field test, enhanced performance in the Adhesive Removal and Rotarod tests, and decreased structural changes in brain tissues. Histological examination revealed reduced neuronal damage in multiple cortical regions, with a significant increase in normal, unchanged neurons compared to placebo groups. Comparison of the blood concentrations of labeled Na125I cortexin depending on the type of administration showed similar distribution profiles in brain tissues, primarily dependent on its blood concentration, which was influenced by the route of administration. Conclusions: The results indicate that brain polypeptides (cortexin), administered either intramuscularly or rectally, can reach the systemic circulation and cross the blood-brain barrier, as demonstrated by our distribution studies using radiolabeled preparations. These polypeptides exert comparable neurotropic effects in models of mental and physical developmental delays in offspring caused by neonatal trauma or the toxic effect of ethanol in late pregnancy in rats. Full article

Background/Objectives: Agarwood has a good neuroprotective effect and is often used to relieve anxiety and treat insomnia. This study compared the similarities and differences in the chromone components of two types of agarwood. It further investigated the absorption and brain distribution characteristics of these components in rats and their neuroprotective effects mediated through anti-neuroinflammatory pathways. Methods: This study confirmed, through ITS2 barcoding and chloroplast genome analysis, that both the ordinary and Qi-Nan agarwood are derived from Aquilaria sinensis. A comparative analysis of chromones in ethanol extracts derived from ordinary and Qi-Nan agarwood, as well as those capable of penetrating the blood-brain barrier in vivo, was conducted using UPLC-Q-TOF-MS. Subsequently, an in vitro neuroinflammatory model was established via lipopolysaccharide (LPS)-stimulated BV-2 cells to evaluate the anti-neuroinflammatory activity of differential chromones. Results: UPLC-Q-TOF-MS characterization revealed the chromone components in the two types of agarwood: A total of 81 chromone compounds were identified in the ethanol extracts of ordinary agarwood (OAE) (20 THPECs, 42 FTPECs, and 19 BI), while 41 were identified in the ethanol extracts of Qi-Nan agarwood (QNE) (11 THPECs and 30 FTPECs). Pharmacokinetic analysis in rats showed that 14 components from OAE (eight THPECs and six FTPECs) penetrated the rat serum, and 10 of these 14 components penetrated the blood–brain barrier (BBB). Twelve FTPECs from QNE penetrated the rat serum, all of which penetrated the BBB. The total peak area of the total ion current (TIC) was calculated for the samples, and the TIC of the serum was compared to that of the brain tissue from the same rat to roughly estimate the ratio. The results demonstrated that the capability of FTPECs to traverse the blood–brain barrier is substantially superior to that of THPECs. Correspondingly, only FTPECs were detected using DESI-MS imaging; no THPECs were detected in rat brain tissue, and DESI-MS imaging localized FTPECs to neuroanatomic regions (cerebral cortex, thalamus, and hippocampus). In vitro neuroinflammatory assays revealed the superior anti-inflammatory efficacy of QNE over OAE (IL-6/TNF-α suppression, p < 0.05), correlating with its FTPEC-rich composition. Conclusions: Structure–activity relationships identified FTPECs as potent inhibitors of pro-inflammatory cytokines, exhibiting enhanced BBB penetration (blood–brain relative abundance > 1). These findings establish FTPECs as prioritized candidates for CNS-targeted therapeutics, with QNE’s pharmacological superiority attributed to its FTPEC dominance and optimized BBB transit capacity. Full article

The development of targeted drugs for diseases of the central nervous system (CNS) is a significant challenge due to the structural complexity and functional specificities of these systems. Recently, exosomes have emerged as a promising therapeutic platform, given their unique capacity to traverse the blood-brain barrier and deliver bioactive molecules to target cells. This review examines recent advances in exosome research with a particular focus on CNS diseases, emphasizing their role as carriers of therapeutic cargo, including proteins, RNAs, and lipids. Nevertheless, significant challenges remain before exosome-based therapies can be translated from preclinical research to clinical applications. These include the need for scalable production and standardized isolation methods. Despite these hurdles, ongoing studies continue to shed light on the mechanisms of exosome-mediated neuroprotection and neurodegeneration. This paves the way for innovative therapeutic strategies to address CNS disorders. Full article

Cerebral small vessel disease (cSVD) is a common cause of stroke and dementia. Ageing, hypertension, hyperglycaemia, and smoking make up the biggest risk factors for cSVD. They individually or collectively increase the levels of reactive oxygen species, pro-inflammatory cytokines and matrix metalloproteinases, decrease the bioavailability of nitric oxide, and, in the process, compromise the structural integrity and function of the vascular endothelium, blood–brain barrier, and brain parenchyma. These then appear as white matter hyperintensities, enlarged perivascular spaces, cerebral microbleeds, and atrophy in cerebral imaging. As there is currently no curative therapy for cSVD, prevention or delay of cSVD remains of particular importance to preserve quality of life for as long as possible. Bearing that in mind, this review explores whether drugs used for other neurovascular conditions may prevent neuroinflammation and oxidative damage and effectively maintain endothelial function and blood–brain barrier integrity. It also examines whether potential benefits may be extended to cSVD. The list of drugs includes anti-anginal drugs, acetylcholine esterase inhibitors, β-hydroxy β-methylglutaryl-CoA reductase inhibitors, lithium drugs, phosphodiesterase inhibitors, oral antihyperglycaemic drugs, and tetracycline antibiotics. This review discusses the mechanisms of action of these agents and critically evaluates preclinical, translational, and clinical research pertaining to cSVD. Full article

In recent decades, substantial evidence has highlighted the integral roles of neuroglia, particularly astrocytes, microglia, oligodendrocytes, and ependymal cells, in the regulation of synaptic transmission, metabolic support, and immune mechanisms within the central nervous system. In addition to their structural role, these cells actively modulate neurotransmitter homeostasis and influence neuronal plasticity, thereby affecting cognition, mood, and behavior. This review discusses how neuroglial alterations contribute to the pathophysiology of five common psychiatric disorders: major depression, bipolar disorder, anxiety disorders, attention-deficit/hyperactivity disorder (ADHD), and schizophrenia. We synthesized preclinical and clinical findings illustrating that glial dysfunction, including impaired myelination and aberrant neuroinflammatory responses, often parallels disease onset and severity. Moreover, we outline how disruptions in astrocytic glutamate uptake, microglia-mediated synaptic pruning, and blood–brain barrier integrity may underlie the neurobiological heterogeneity observed in these disorders. The therapeutic implications range from anti-inflammatory agents to investigational compounds that aim to stabilize glial function or promote remyelination. However, challenges due to interindividual variability, insufficient biomarkers, and the multifactorial nature of psychiatric illnesses remain. Advances in neuroimaging, liquid biopsy, and more precise molecular techniques may facilitate targeted interventions by stratifying patient subgroups with distinct glial phenotypes. Continued research is essential to translate these insights into clinically efficacious and safe treatments. Full article

Exposure of organisms to nanoplastics (NPs) is inevitable given their global abundance and environmental persistence. Polyethylene terephthalate (PET) is a common plastic used in a wide range of products, including clothing and food and beverage packaging. Recent studies suggest that NPs can cross the blood-brain barrier and cause potential neurotoxicity. It is widely known that aggregation of amyloid beta (Aβ) peptides in the brain is a pathological hallmark of Alzheimer’s disease (AD). While the impact of nanoplastics such as polystyrene (PS) on amyloid aggregation has been studied, the effects of PET NPs remain unexplored. In this study, we examined the effect of PET NPs of different sizes (PET_50nm and PET_140nm) and concentrations (0, 10, 50, and 100 ppm) on the fibrillation of Aβ_1-40. Our results showed that the presence of PET_50nm as well as PET_140nm decreased the lag phase of the fibrillation processes in a dose- and size-dependent manner from 6.7 ± 0.08 h for Aβ in the absence of PET (Aβ_control) to 3.1 ± 0.03 h for PET_50nm and 3.8 ± 0.06 h for PET_140nm. CD spectroscopy showed that PET_50nm significantly impacts the structural composition of Aβ aggregates. A significant rise in antiparallel β-sheet content and β-turn structure and a substantial reduction in other structures were observed in the presence of 100 ppm PET_50nm. These changes indicate that higher concentrations (100 ppm) of PET_50nm promote more rigid and uniform peptide aggregates. Although PET_50nm NPs influence the kinetics of aggregation and secondary structure, the overall morphology of the resulting fibrils remains largely unaltered, as seen using transmission electron microscopy. Also, the local cross-β structure of the fibrils was not affected by the presence of PET_50nm NPs during fibrillation, as confirmed using ¹³C solid-state NMR spectroscopy. Overall, these findings show that PET NPs accelerate amyloid fibril formation and alter the secondary structure of Aβ fibrils. These results also indicate that the accumulation of PET-NPs in the brain may facilitate the progression of various neurodegenerative diseases, including Alzheimer’s disease. Full article