Search Results (2,210)

Ferroptosis has emerged as a critical mechanism linking iron dysregulation, oxidative stress, and neurodegeneration in amyloid-associated pathologies. Building on our previous work, which identified compound 20 as a promising antioxidant and neuroprotective agent, the present study investigates the molecular mechanisms underlying its protective activity against amyloid-induced ferroptosis in human neuroblastoma SH-SY5Y cells exposed to Aβ(25–35). Compound 20 (3-(((4-hydroxybenzyl)(methyl)amino)methyl)-1-methyl-N-(2-(piperazin-1-yl)ethyl)-1H-indole-5-carboxamide) markedly counteracted Aβ(25–35)-induced ferroptotic damage by restoring intracellular glutathione levels, depleting the labile iron pool, and suppressing lipid peroxidation. In parallel, the compound significantly rescued mitochondrial membrane potential and attenuated endoplasmic reticulum (ER) expansion associated with ER stress, thereby preserving cellular homeostasis under oxidative challenge. These protective effects were further corroborated by real-time PCR analysis, which revealed the modulation of key genes involved in the oxidative stress response, endoplasmic reticulum stress, and inflammatory pathways. To gain a systems-level insight into these mechanisms, untargeted ¹H-NMR metabolomic profiling was performed. This analysis confirmed the activation of antioxidant pathways and disclosed a significant modulation of energy metabolism and GABA-related pathways, both of which are closely linked to redox balance and neuronal resilience. Overall, these findings demonstrate that compound 20 drives metabolic reprogramming that orchestrates its multifactorial protective effect against Aβ(25–35)-induced ferroptosis by coordinating antioxidant defense, iron homeostasis, and ER stress mitigation. Full article

Oral mucosal repair is a redox-regulated process that may be impaired by diabetes, chronic inflammation, infection, and chemotherapy- or radiotherapy-induced oral mucositis. Reactive oxygen species (ROS) support host defense, epithelial migration, angiogenesis, extracellular matrix remodeling, and adaptive repair when their production is transient and compartmentalized. In contrast, persistent ROS promote lipid, protein, and DNA oxidation, mitochondrial dysfunction, and extracellular matrix damage. Photobiomodulation (PBM) is increasingly used to support oral tissue repair, but its effects should be interpreted as dose- and context-dependent redox modulation rather than as simple antioxidant activity. This narrative review synthesizes oxidative stress biomarkers and redox-sensitive pathways relevant to oral mucosal repair and PBM, including oxidant–antioxidant balance, lipid and protein oxidation, oxidative DNA damage, antioxidant defense, thiol/disulfide homeostasis, mitochondrial and NADPH oxidase-derived ROS, Nrf2/HO-1, NF-κB, HIF-1α/VEGF, MAPK/ERK, PI3K/Akt, and MMP/TIMP signaling. The review emphasizes the distinction between transient mitochondrial ROS/nitric oxide signaling and sustained NADPH oxidase-driven oxi-inflammatory stress. It proposes a practical redox-guided framework for biomarker selection, PBM response interpretation, and future study design, while noting that this framework remains conceptual and is not yet a validated clinical decision algorithm. Full article

Lead exposure remains a pervasive environmental and public health threat, imposing a substantial burden of neurodevelopmental and cognitive dysfunction, yet safe mechanism-oriented interventions remain limited. Genistein, a soybean-derived isoflavone with antioxidant and neuroprotective potential, may counter heavy metal-induced neural injury; however, whether its efficacy is associated with redox–metabolic remodeling is unclear. Here, we evaluated genistein in lead-exposed C57BL/6J mice and lead-challenged HT22 hippocampal neurons. Genistein improved novel-arm exploration and spatial memory without altering locomotor or swimming performance, and attenuated neuronal disorganization and apoptosis in hippocampal CA1, CA3 and dentate gyrus regions. These protective effects were accompanied by reduced blood and hippocampal lead accumulation, restored glutathione redox balance, enhanced antioxidant capacity, preserved mitochondrial integrity, and suppressed Bax/Caspase-3-associated apoptotic signaling. Importantly, because genistein also reduced hippocampal lead accumulation, the in vivo neuroprotection may reflect both reduced target-tissue lead burden and improved glutathione-related redox homeostasis. Untargeted metabolomics identified 59 genistein-responsive metabolites enriched mainly in glutathione metabolism, oxidative phosphorylation, and ascorbate/aldarate metabolism, linking metabolic remodeling to behavioral recovery and reduced oxidative-apoptotic injury. In HT22 cells, blockade of glutathione synthesis by buthionine sulfoximine markedly weakened genistein-mediated cytoprotection, mitochondrial membrane potential recovery, and apoptosis inhibition. Collectively, genistein mitigates lead-induced hippocampal neurotoxicity and cognitive impairment by restoring glutathione-centered redox–mitochondrial homeostasis, supporting its further development as a mechanistically defined dietary candidate for environmental pollutant-associated neural injury. Full article

Reproductive inefficiency associated with impaired oocyte competence and embryonic loss remains a major limitation in livestock production. Although glycine is classified as a non-essential amino acid, its endogenous synthesis is often insufficient to meet increased metabolic demands during gestation and early embryonic development. This suggests that glycine has a conditionally essential role in reproductive physiology. However, the mechanisms through which glycine integrates metabolic and signaling processes to regulate reproductive outcomes are not fully understood. This review summarizes the recent advances in understanding glycine’s role in animal reproduction, emphasizing its function as a metabolic regulator rather than merely a structural component. Glycine contributes to reproductive processes by maintaining redox homeostasis, supporting mitochondrial function and stabilizing cellular environments as part of its osmolyte function during critical developmental stages. Additionally, glycine participates in one-carbon metabolism, influencing nucleotide synthesis and epigenetic regulation. Furthermore, emerging evidence suggests that glycine may modulate key signaling pathways, including the AMP-activated protein kinase (AMPK)-mechanistic target of rapamycin complex 1 (mTORC1) pathway. Consistent with these mechanistic roles, glycine supplementation has been associated with improvements in oocyte maturation and embryonic development, particularly in vitro. These findings highlight the potential of glycine as a dietary or culture medium supplement to enhance reproductive performance in livestock. However, most current evidence is derived from in vitro systems, and the translation of these findings into livestock production strategies requires validation through well-designed in vivo studies. Full article

Metabolic and cardiometabolic diseases are closely associated with mitochondrial dysfunction and redox imbalance. Ubiquinol–cytochrome c reductase core protein 2 (UQCRC2), a non-catalytic structural core subunit of mitochondrial respiratory chain Complex III, is increasingly recognized as a regulator of Complex III integrity, electron transfer, oxidative phosphorylation, and mitochondrial redox homeostasis. Under metabolic stress, reduced expression or functional impairment of UQCRC2 may promote electron leakage, mitochondrial reactive oxygen species (mtROS) generation, lipid peroxidation, impaired antioxidant defense, and disrupted glucose–lipid metabolism. These alterations may contribute to insulin resistance (IR), metabolic dysfunction-associated steatotic liver disease (MASLD), obesity, and cardiovascular disease (CVD). This review summarizes current evidence linking UQCRC2 dysfunction to mitochondrial bioenergetic failure, oxidative stress, inflammatory signaling, and cardiometabolic injury. We further discuss redox-regulatory pathways, including Nrf2, AMPK–SIRT1–PGC-1α, glutathione metabolism, and mitophagy, as well as pharmacological agents and natural compounds that may modulate UQCRC2-related mitochondrial responses. Collectively, these findings highlight UQCRC2 as a redox-sensitive mitochondrial node linking Complex III dysfunction to cardiometabolic injury and targeted redox-based interventions. Full article

The pineal gland regulates circadian physiology through the periodic production of melatonin (MLT). In addition to its established role as a chronobiotic agent, MLT regulates redox homeostasis and mitochondrial physiology. Mitochondria and redox-active molecules, particularly reactive oxygen species (ROS), play essential roles in reproduction, including gamete physiology, fertilization, and early embryonic development. Although excessive oxidative stress (OS) impairs fertility, controlled ROS signaling is necessary for normal reproductive function. This comprehensive review synthesizes current evidence regarding MLT as a key intermediary linking circadian signaling with mitochondrial physiology and redox homeostasis. We discuss molecular pathways through which MLT regulates mitochondrial function, including activation of the Nrf2 signaling pathway, modulation of mitochondrial permeability transition, regulation of electron transport chain (ETC) efficiency, and apoptotic signaling. Furthermore, this study investigates MLT’s ability to scavenge free radicals and activate antioxidant defense mechanisms. Moreover, we review novel findings regarding the effects of MLT in experimental animals and humans, assisted reproductive technologies (ART) such as in vitro fertilization (IVF), and consider the translational significance of the hormone as an enhancer of fertility. We also highlight gaps in the literature, including methodological inconsistencies, supraphysiologic doses, and insufficient data from large human cohorts. Lastly, we discuss an integrative model whereby MLT may function as an important regulator of mitochondrial redox balance, with potential implications for reproductive physiology and reproductive outcomes, and propose new avenues for investigation. Full article

Osmotic stress severely limits the growth and development of tomato (Solanum lycopersicum L.) by reducing cellular water potential, disrupting redox homeostasis, and impairing physiological functions. Micro–nano bubble (MNB) treatment can increase dissolved oxygen in the root-zone solution and improve the root-zone environment, which may benefit root metabolic activity and stress adaptation. However, the underlying molecular mechanisms are still not elucidated. To explore the underlying molecular mechanisms of how MNB-mediated root oxygenation alleviates osmotic stress in tomato, we have integrated the physiological and biochemical alterations, variable-pressure scanning electron microscopy (VP-SEM), and transcriptomic analysis (RNA-seq) under osmotic stress. The results revealed that MNBs significantly reduced PEG-induced wilting and decreased reactive oxygen species (ROS) accumulation and relative electrical conductivity (REC). Indeed, MNBs also markedly upregulated the expression of root aquaporins PIP2.7 and PIP2.4, suppressed the expression of NCED1 in leaves, and increased levels of endogenous growth-promoting hormones, including IAA and GA₃, under osmotic stress. VP-SEM observations showed that MNB-treated plants exhibited a relatively more open stomatal appearance compared with PEG-treated plants. Together, these findings suggest that MNBs mitigate PEG-induced osmotic stress in tomato, potentially by improving the root-zone aeration environment and coordinating water transport-related gene expression, antioxidant defense, and hormonal balance. These results provide a promising physical approach and theoretical basis for improving tomato stress tolerance under osmotic stress. Full article

Driven by increasingly severe drought stress associated with global warming, this study investigated a synthetic microbial community, SynCom-SASW01, with strong stress tolerance and plant growth-promoting potential, and systematically elucidated its mechanisms for enhancing drought resistance in wheat (Triticum aestivum L.). Dual-site field trials demonstrated that SynCom-SASW01 significantly alleviated drought-induced growth suppression, increasing grain yields by 10.42% and 8.52% at the Hohhot and Hulunbuir sites, respectively. This improvement was primarily associated with increased effective tiller number and enhanced root vigor. Physiologically, inoculation promoted root proline and glutathione accumulation and enhanced antioxidant enzyme activities, including superoxide dismutase, thereby reducing malondialdehyde levels. Environmental analyses showed that the consortium established rhizosphere “micro-reservoirs” through exopolysaccharide secretion, improving soil relative water content and the availability of alkali-hydrolyzable nitrogen and phosphorus. High-throughput sequencing revealed that SynCom-SASW01 reshaped the endosphere microbiome through early colonization priority effects, selectively enriching beneficial taxa such as Pseudomonas. Functional prediction indicated upregulated branched-chain amino acid biosynthesis, promoting osmotic adjustment and redox homeostasis. These findings provide a microbiome-based strategy for stabilizing wheat productivity in arid regions. Full article

Background: Systemic arterial hypertension (SAH) induced by Nω-nitro-L-arginine methyl ester (L-NAME) is a well-established model characterized by nitric oxide (NO^●) synthase inhibition and vascular dysfunction. The transient receptor potential vanilloid 1 (TRPV1) regulates Ca²⁺ flux and may contribute to mitochondrial homeostasis. We hypothesized that TRPV1 activation modulates mitochondria function and attenuates cardiac damage during SAH. Methods: Hypertension was induced in Wistar rats by administration of L-NAME (200 mg/L) for 40 days. During the last four days, hypertensive animals received capsaicin (5 mg/kg/day), capsazepine (6 mg/kg/day), or their combination. Cardiac function was evaluated in isolated hearts using the Langendorff perfusion system. Myocardial tissue viability was assessed by triphenyltetrazolium chloride (TTC) staining, and mitochondrial function was evaluated by measuring respiratory control and apoptosis-related proteins. Results: Capsaicin treatment was associated with significant cardioprotective effects in hypertensive rats. Although the findings are consistent with a role of TRPV1 activation in mediating these effects, the partial protection observed with capsazepine suggests that TRPV1-independent mechanisms may also contribute. Conclusions: TRPV1 activation contributes to cardioprotection in SAH, likely through preservation of mitochondrial function and redox balance. However, additional mechanisms beyond TRPV1 modulation may also participate in the observed protective effects. Further studies—including direct assessment of mitochondrial Ca²⁺ flux and the use of more selective or genetic approaches—are currently underway to clarify the underlying mechanisms. Full article

Background/Objectives: Melatonin is a multifunctional indoleamine with recognized antitumor activity; however, its subtype-specific effects in breast cancer remain incompletely understood. This study aimed to investigate the impact of melatonin on cellular and metabolic processes associated with tumor progression in two human breast cancer cell lines representing distinct molecular subtypes: MCF-7 (luminal A) and MDA-MB-468 (triple-negative). Methods: Breast cancer cells were treated with micromolar concentrations of melatonin, and assays were performed to evaluate cell viability, migration, invasion, mitochondrial status, redox balance, protein expression, and biogenic amine profiles. Results: Melatonin significantly reduced cell viability, migration, and invasion in both cell lines, with more pronounced effects in MCF-7 cells. At the molecular level, melatonin downregulated key metabolic and hypoxia-related proteins, including GAPDH and HIF-1α, while citrate synthase was selectively reduced in MCF-7 cells, indicating suppression of mitochondrial metabolic capacity. This was accompanied by a reduction in mitochondrial status, reflected by decreased MitoGreen staining. Melatonin also induced redox imbalance, as evidenced by increased lipid peroxidation and protein carbonylation, along with subtype-dependent modulation of antioxidant enzymes. In addition, alterations in biogenic amine profiles were observed, suggesting broader metabolic remodeling. Conclusions: Collectively, these findings demonstrate that melatonin exerts subtype-dependent antitumor effects by targeting metabolic, mitochondrial, and redox pathways, supporting further investigation of melatonin as a potential therapeutic adjuvant in breast cancer, while recognizing that the concentrations used in this study exceed physiological circulating levels. Full article

Copper ions (Cu²⁺) and intracellular biothiols are tightly coupled in cellular redox regulation, where copper–thiol coordination governs oxidative stress and metal homeostasis. However, analytical platforms capable of sequentially monitoring Cu²⁺ and biothiols within a single molecular system remain scarce. Herein, we report a coumarin-based fluorescent probe XDP that enables sequential ON–OFF–ON sensing of Cu²⁺ and biothiols through a coordination–competition mechanism. The imine (C=N) site of XDP selectively coordinates Cu²⁺, leading to fluorescence quenching arising from coordination-induced electronic perturbation and enhanced nonradiative decay. The probe exhibits a linear response toward Cu²⁺ over 1–80 μM with a detection limit of 0.108 μM. Subsequent competitive binding of biothiols (GSH, Cys, and Hcy) releases Cu²⁺ from the complex, thereby restoring fluorescence and enabling detection within 1–30 μM with submicromolar sensitivity. XDP also displays a large Stokes shift (135 nm), which minimizes spectral overlap and improves signal reliability. Notably, Cu²⁺ binding triggers a distinct color change that supports naked-eye detection and smartphone-based RGB quantification. The probe further enables visualization of Cu²⁺ and thiol-triggered signal recovery in living cells and zebrafish. This work establishes a versatile analytical platform for probing copper–thiol interactions in environmental and biological systems. Full article

Perfluorooctane sulfonate (PFOS) is a persistent organic pollutant widely detected in aquatic ecosystems, but its subcellular targets and the mechanisms by which it disrupts light resource utilization in photosynthetic protozoa remain poorly understood at concentrations spanning environmentally typical to supra-environmental levels. Here, Euglena gracilis G.A. Klebs was exposed to PFOS at concentrations spanning environmentally typical (0.5 µg/L), hotspot-relevant (5 µg/L), and supra-environmental (50 µg/L) levels. Subcellular distribution, phototaxis, photosynthetic light reactions, and energy metabolism were investigated using isolated chloroplast assays, transcriptomics, and proteomics. TEM-EDS mapping revealed pronounced fluorine signal enrichment, attributable to PFOS, in the eyespot and chloroplasts. Eyespot fluorine enrichment was associated with impaired phototactic motility and an altered light perception threshold. PFOS did not acutely inhibit the maximum photochemical efficiency of photosystem II (Fv/Fm); instead, a transient upregulation of photosynthesis-related genes was observed, which weakened with prolonged exposure, whereas the photosynthetic electron transport rate (ETR) was significantly reduced. PFOS significantly reduced ATP levels and ETR, while Fv/Fm remained unchanged and non-photochemical quenching (NPQ) was elevated. Isolated chloroplast assays revealed that PFOS inhibits Mg²⁺-dependent ATP hydrolytic activity in the chloroplast-enriched fraction and impairs thylakoid electron transport, consistent with impaired chloroplast ATP synthase function, though the specific molecular target and mechanism remain to be conclusively demonstrated. Transcriptomic and proteomic analyses revealed compensatory upregulation of photosynthesis pathways but suppression of ATP synthesis and redox homeostasis. Collectively, our results suggest that PFOS impairs chloroplast ATP synthase function, accompanied by reduced ETR and elevated NPQ. Together with the eyespot-associated phototaxis impairment, these effects suggest that PFOS may dually disrupt light acquisition (behavioral) and light conversion (physiological) in E. gracilis. This dual impairment may compromise the ecological fitness of Euglena in PFOS-contaminated environments, especially under prolonged exposure. It should be noted that the subcellular fluorine mapping is qualitative, the phototaxis assay reflects population-level responses, and the ATP synthase impairment interpretation is indirect; the proposed mechanistic model remains a hypothesis requiring further direct experimental validation. Full article

Young barley, derived from the early vegetative stage of Hordeum vulgare L., constitutes a plant-based functional ingredient whose phytochemical profile differs markedly from that of mature grain. Two principal commercial forms exist—dried grass powder and juice-derived products—differing in matrix composition and bioactive compound concentration. This narrative review critically evaluates the current knowledge on the phytochemical composition, biological activity, and translational relevance of young barley preparations considered as a functional plant food. The phytochemical spectrum is dominated by C-glycosyl flavones, particularly saponarin and lutonarin, alongside phenolic acids, chlorophylls, enzymatic antioxidants, vitamins, and minerals. Experimental evidence implicates the modulation of redox homeostasis, inflammatory signaling, and metabolic regulators as the primary biological mechanisms. In vitro studies additionally demonstrate antiproliferative activity in human cancer cell lines and immunomodulatory properties mediated by polysaccharide-rich fractions, extending the biological profile of young barley beyond classical antioxidant activity. Although preclinical models consistently demonstrate antioxidant and metabolic effects, high experimental doses and limited preparation standardization restrict the direct extrapolation to human supplementation contexts. Available clinical trials suggest modest improvements in selected lipid, glycemic, and oxidative stress markers; yet, most are small in scale and brief in duration. Agronomic variables including fertilization strategy and soil composition represent additional, underappreciated sources of phytochemical variability and safety concern. Overall, the current evidence supports the biological plausibility of young barley as a functional plant food; yet, the clinical data remain preliminary. Future research should prioritize preparation standardization, dose–response characterization, and agronomic transparency to strengthen translational reliability. In conclusion, young barley preparations represent a biologically plausible functional plant food ingredient with preliminary clinical support, pending confirmation from adequately powered, standardised randomised controlled trials. Full article

SQSTM1/p62 is a multifunctional scaffold protein that plays important roles in selective autophagy and cellular redox homeostasis. While phosphorylation-dependent regulation of p62 has been extensively studied, the functional significance of oxidative modification remains incompletely understood. Our previous studies showed that the natural small compound Alternol induces cancer cell-specific killing via a xanthine oxidase-mediated strong oxidative stress. In this study, we investigated p62-associated oxidative responses under Alternol-induced oxidative stress conditions in prostate cancer cells. Using biochemical assays and cell-based models, we found that Alternol treatment was associated with the accumulation of oxidized and high-molecular-weight p62 species, accompanied by altered KEAP1 association and increased Nrf2-associated signaling. Furthermore, Alternol-induced p62 oxidative modification was associated with autophagy-related responses and adaptive cellular survival under oxidative stress conditions. Disruption of the Cys105/113-dependent oxidative modification response attenuated Nrf2-associated transcriptional activity and increased cellular sensitivity to Alternol treatment. Collectively, our findings support an association between p62 oxidative modification and redox-responsive autophagy- and antioxidant-associated signaling pathways under Alternol-induced oxidative stress conditions, providing new insight into adaptive stress responses in prostate cancer cells. Full article

In vitro maturation (IVM) is a critical step affecting the efficiency of bovine in vitro embryo production; however, oxidative stress during in vitro culture can impair oocyte quality and subsequent developmental competence. This study investigated the effects of cysteine supplementation on bovine oocyte IVM, redox homeostasis, mitochondrial status, and transcriptomic changes. Bovine cumulus-oocyte complexes were cultured in IVM medium supplemented with 0, 25, 50, 75, 100, or 125 μM cysteine, and 75 μM was identified as the optimal concentration. Compared with the control group, 75 μM cysteine increased the first polar body extrusion rate from approximately 78% to 81% and improved the fertilization/cleavage rate from approximately 74% to 82%. It also significantly increased the proportions of 2-cell, 4-cell, and 8-cell embryos, whereas morula and blastocyst rates were not significantly affected. At the cellular level, 75 μM cysteine significantly reduced ROS levels and increased GSH content, as indicated by changes in relative fluorescence intensity. JC-1 staining showed that the JC-1 monomer signal decreased from approximately 16.0 to 13.5, whereas the JC-1 aggregate signal increased from approximately 13.2 to 14.8, indicating improved mitochondrial membrane potential status. In addition, lipid droplet fluorescence intensity increased from approximately 11.8 to 13.4, mitochondrial fluorescence intensity increased from approximately 6.0 to 7.0, and cytoskeletal fluorescence intensity showed no significant difference between groups. Smart-seq2 transcriptomic analysis identified 1935 differentially expressed genes, including 1778 upregulated and 157 downregulated genes, which were mainly enriched in translation, ribosomal structural components, RNA binding, oxidative phosphorylation, and metabolism-related pathways. qRT-PCR further confirmed the upregulation of key genes, including NDUFS2, VDAC3, ANXA2, MTHFD1L, and SCD. Overall, 75 μM cysteine improves bovine oocyte IVM quality by enhancing antioxidant capacity, improving mitochondrial membrane potential, increasing lipid-derived energy substrate storage, and regulating genes related to energy metabolism and developmental competence. Full article