Search Results (670)

Redox homeostasis is the balance between oxidative processes and antioxidant defenses and is fundamental to cellular integrity. This review critically synthesizes current evidence on the phytochemical composition, redox-modulating mechanisms, and therapeutic bioactivities of Fagonia cretica L. (F. cretica), with the aim of evaluating its translational potential as a natural antioxidant and anticancer agent. F. cretica has emerged as a phytochemically rich candidate containing highly bioactive secondary metabolite for redox-targeted therapeutic applications. Its diverse secondary metabolite profile, including alkaloids, flavonoids, tannins, saponins, terpenoids, glycosides, and phenolic compounds, confers broad biological activity. Bioactive constituents, particularly kaempferol, catechin, quercetin, and arbutin, directly neutralize reactive oxygen species (ROS) and modulate inflammatory pathways through inhibition of COX-1, COX-2, and nitric oxide production. These compounds influence important major ROS-sensitive redox signaling pathways: activation of the Keap1/Nrf2/ARE axis to upregulate cytoprotective genes such as HO-1, NQO1, and GCL, suppression of the NF-κB pathway to attenuate pro-inflammatory cytokine transcription, including TNF-α, IL-1β, and IL-6, and interference with the MAPK-PI3K/Akt cascade to disrupt aberrant cancer cell survival and proliferation. Bioactive compound-rich extracts of F. cretica exhibit anticancer activity in MCF-7 breast cancer cells by inducing DNA damage, cell cycle arrest, and apoptotic signaling through the FOXO3a/p53 pathways. Similar effects have been reported in colorectal (HCT-116) and prostate (PC-3) cancer cells through DNA (cytosine-5)-methyltransferase 1 (DNMT1) downregulation, oxidative stress induction, and ER-β activation. Moreover, these extracts demonstrate cytotoxic effects in HepG2 and Caco-2 intestinal cancer cells, often associated with topoisomerase inhibition and caspase activation. Despite encouraging preclinical evidence, systematic studies encompassing pharmacokinetic profiling, toxicological characterization, and human clinical trials remain essential to translate these findings into safe, evidence-based therapeutic applications. Full article

Asthma is a heterogeneous chronic airway disease in which oxidative stress (OS) plays a central mechanistic role beyond classical immune-mediated inflammation. Reactive oxygen and nitrogen species (ROS/RNS), generated by recruited inflammatory cells and activated airway structural cells, drive epithelial injury, mucus hypersecretion, airway remodeling, and modulate key transcription factors including nuclear factor kappa B (NF-κB) and mitogen-activated protein kinase (MAPK) pathways. This review synthesizes current evidence on the multilevel redox-based determinants of asthma severity, spanning from genetic polymorphisms to circulating biomarkers. We examine serum antioxidant enzymes, superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), peroxiredoxins (PRDXs), and the thioredoxin (Trx) system as dynamic indicators of systemic redox status and disease severity, alongside oxidative enzymes including NADPH oxidases and dual oxidases (NOX/DUOX), xanthine oxidase (XO), and myeloperoxidase (MPO) that serve as upstream sources of airway oxidant burden. Functional genetic polymorphisms in antioxidant genes (SOD2, CAT, glutathione S-transferase mu 1/glutathione S-transferase theta 1 (GSTM1/GSTT1), heme oxygenase-1 (HO-1), NAD(P)H quinone dehydrogenase 1 (NQO1), nuclear factor erythroid 2-related factor 2/Kelch-like ECH-associated protein 1 (Nrf2/KEAP1)) and oxidative enzyme genes including nitric oxide synthase 1/2/3 (NOS1/2/3), MPO, cytochrome b-245 alpha chain (CYBA), and xanthine dehydrogenase (XDH) are reviewed as modulators of individual redox capacity and asthma susceptibility, with particular attention to gene–environment interactions. We further discuss oxidative damage biomarkers, including malondialdehyde (MDA), 8-isoprostanes, 4-hydroxynonenal, 8-oxo-7, 8-dihydro-2′-deoxyguanosine, protein carbonyls, 3-nitrotyrosine, and advanced oxidation protein products as indicators of lipid, DNA, and protein oxidation that correlate with disease activity and control. The roles of micronutrient cofactors in modulating antioxidant enzyme function and their potential as contextual biomarkers are also addressed. Additionally, emerging evidence on microRNAs (miRNAs) linked to OS biology in asthma is presented. Finally, we critically evaluate the challenges limiting clinical translation, including biomarker non-specificity, analytical variability, gene–environment complexity, and the absence of standardized reference ranges. This integrated framework supports the development of multilevel redox prognostic panels combining genetic, enzymatic, and oxidative damage readouts for improved asthma phenotyping, severity stratification, and personalized therapeutic approaches. Full article

This study assessed the effects of dietary honeycomb supplementation on laying performance, intestinal inflammation, ovarian function, and yolk precursor synthesis in laying hens. A total of 320 Dawu Golden Phoenix laying hens (288-d-old) were randomly assigned into four treatment groups with eight replicates of 10 hens each. Hens were provided diets containing 0, 0.5, 1.0, or 2.0 g/kg honeycomb for 30 d. Dietary honeycomb significantly increased average egg weight, average daily feed intake, and laying rate, while decreasing the feed conversion ratio (p < 0.05). It enhanced serum antioxidant capacity, as reflected by higher GSH, SOD, and CAT activity (p < 0.05). Meanwhile, honeycomb modulated the expression of Nrf2/Keap1 pathway-related genes, accompanied by increased expression of downstream antioxidant-related genes. Additionally, honeycomb downregulated intestinal inflammatory- and apoptosis-related factors (p < 0.05), which effectively alleviated intestinal inflammation responses. In the liver, honeycomb showed favorable histological changes, including fewer lipid droplets and less vacuolar degeneration. Furthermore, it decreased serum ALT, AST, and TG levels and promoted yolk precursor synthesis by upregulating genes associated with lipid transport and vitellogenesis (p < 0.05). In the ovary, honeycomb optimized ovarian morphology and follicle development; elevated serum FSH, E2, and MLT levels; and enhanced the expression of steroidogenesis-related genes (p < 0.05), thereby promoting steroid hormone synthesis and reducing follicular atresia. In conclusion, dietary honeycomb supplementation could maintain intestinal health, modulate hepatic and ovarian metabolism functions, promote yolk precursor synthesis, improve follicle development, and consequently, enhance the laying performance of hens. Full article

Nanoplastics (NPs) are emerging aquatic pollutants that may threaten farmed fish health. This study evaluated whether dietary nanocurcumin (NCUR) modulates NP-associated biological disturbances in largemouth bass (Micropterus salmoides). A total of 480 fish (initial weight 11.52 ± 0.02 g) were assigned to four treatments for 21 days: control, 0.2% NCUR, 100 μg/L NPs, and 0.2% NCUR + 100 μg/L NPs. NP exposure significantly reduced growth and feed intake (p < 0.05) and was accompanied by gill, hepatic and intestinal tissue alterations, disturbed serum lipid parameters, changes in hepatic antioxidant enzyme activities, and altered mRNA expression of antioxidant- and metabolism-related genes. Dietary NCUR was associated with partial modulation of several NP-associated responses, including hepatic and intestinal structural alterations, serum lipid changes, adaptive antioxidant enzyme responses, and transcriptional changes in Nrf2/Keap1- and SIRT1/FoxO1-associated genes. However, NCUR did not alleviate NPs-induced gill damage, and NCUR alone also caused branchial histopathological alterations. Therefore, 0.2% NCUR may partially mitigate selected NPs-induced disturbances in M. salmoides, but its independent effects, branchial safety, and pathway-level mechanisms require further investigation. Full article

In medicinal chemistry, halogen substitution is often used to enhance the biological activity of anticancer compounds. Phenethyl isothiocyanate (PEITC), a natural compound found in cruciferous vegetables, exhibits anti-cancer activity by modulating oxidative stress and apoptosis-related pathways. This study compared the effects of PEITC and its chlorinated derivative, Cl-PEITC, on human leukemia cell lines, including multidrug-resistant (MDR) variants that overexpress P-glycoprotein (P-gp). We evaluated cell viability, apoptosis, reactive oxygen species (ROS) production, the modulation of the NRF2/KEAP1 signaling pathway, NF-κB p65 protein expression, DNA fragmentation, and autophagy in SKM-1, MOLM-13 and their MDR variants SKM/VCR and MOLM/VCR cells. Cl-PEITC exhibited stronger antiproliferative and cytotoxic effects than PEITC in all tested cell lines and maintained similar activity in P-gp-positive resistant cells. In contrast, resistant sublines showed reduced sensitivity to PEITC. Cl-PEITC induced higher ROS production and enhanced apoptosis, accompanied by the activation of caspases-3, -8, and -9 and PARP1 cleavage. It also caused more pronounced DNA fragmentation. Both PEITC and Cl-PEITC modulated autophagy-related markers, as demonstrated by increased LC3-II/LC3-I conversion and decreased p62 protein levels. In addition, these compounds modulated NRF2/KEAP1 and reduced NF-κB p65 expression in a concentration-dependent manner. These findings suggest that the chlorination of PEITC enhances its antileukemic activity and could retain its efficacy against P-gp-associated MDR. Full article

Aflatoxin B₁ (AFB₁) causes acute liver injury in livestock. This study evaluated whether Vitamin U could alleviate AFB₁-induced hepatotoxicity in mice. AFB₁ (3 mg/kg) reduced PLT, PCT, and EOS counts, caused hepatic vascular congestion, and decreased GSH-Px activity. Vitamin U (50 mg/kg) significantly improved these hematological parameters, alleviated central venous and sinusoidal congestion, increased T-SOD activity and upregulated IL-10 mRNA expression. However, Vitamin U did not significantly reverse AFB₁-induced elevation of ALP or reduction in GSH-Px, nor did it affect ALT, AST, or protein levels of the Nrf2/Keap1 pathway. Transcriptomic analysis revealed enrichment of DEGs in immune- and cell cycle-related pathways, with no direct enrichment observed in the Nrf2/Keap1 pathway. Vitamin U upregulated Keap1 mRNA expression but did not alter KEAP1 protein levels. In conclusion, Vitamin U partially protects against AFB₁-induced acute liver injury by ameliorating thrombocytopenia, vascular congestion, enhancing T-SOD activity, and upregulating IL-10 expression, providing preliminary experimental evidence for further investigation. Full article

Acetaminophen (APAP) overdose is a major cause of drug-induced liver injury and remains a widely used model of xenobiotic-induced hepatotoxicity. Oxidative stress, mitochondrial dysfunction, and ferroptosis are key events in APAP-mediated liver damage. In this study, we investigated whether L-menthol pretreatment protects against APAP-induced acute liver injury and explored the underlying mechanisms in vivo and in vitro. Male C57BL/6 mice were pretreated with L-menthol (100 mg/kg/day) for 7 days before APAP challenge (300 mg/kg). L-menthol markedly attenuated hepatic necrosis, inflammatory infiltration, and hepatocyte injury, reduced serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities, suppressed IL-1β, IL-6, and TNF-α production, restored hepatic glutathione and superoxide dismutase levels, and decreased malondialdehyde accumulation. Transcriptomic analysis revealed significant enrichment of differentially expressed genes in reactive oxygen species- and ferroptosis-related pathways. In APAP-challenged HepG2 cells, L-menthol improved cell viability, preserved mitochondrial ultrastructure, reduced ferrous iron accumulation, was associated with upregulation of Keap1/Nrf2/HO-1/NQO1 pathway-related proteins, and restored GPX4 expression. Collectively, these findings indicate that L-menthol pretreatment attenuates APAP-induced hepatotoxicity, possibly through enhancement of antioxidant defenses and attenuation of ferroptosis-associated changes, supporting its potential as a preventive hepatoprotective small molecule against xenobiotic-induced liver injury. Full article

Photobiomodulation (PBM) is a non-invasive therapeutic strategy that uses red and near-infrared (NIR) light in the 590–950 nm range to modulate the cellular and molecular pathways involved in retinal homeostasis. At the molecular level, PBM acts primarily through photon absorption by cytochrome c oxidase (CcO, complex IV of the mitochondrial electron transport chain), whose four metal centres—two copper (CuA and CuB) and two heme groups (heme a and heme a₃)—absorb light across approximately 600–1000 nm. Photon capture promotes photodissociation of inhibitory nitric oxide (NO) from the binuclear CuB–heme a₃ centre, accelerates electron transfer, restores the proton-motive force and increases ATP synthesis. These primary events trigger a coordinated molecular programme that includes (i) transient mitochondrial reactive oxygen species (ROS) bursts that activate the Nrf2/Keap1/ARE axis and upregulate phase II antioxidant enzymes (HO-1, NQO1, GCLC, SOD2, catalase, GPx); (ii) calcium- and cAMP-dependent secondary signalling that converges on PI3K/Akt, MAPK/ERK, AMPK and mTOR pathways; (iii) suppression of NF-κB-driven cytokine production (TNF-α, IL-1β, IL-6) and of NLRP3 inflammasome activation; (iv) downregulation of the HIF-1α/VEGF axis, particularly at 590 nm; (v) anti-apoptotic remodelling of the Bcl-2/Bax ratio with reduced cytochrome c release and caspase-3/9 activation; and (vi) PGC-1α/TFAM/NRF1-driven mitochondrial biogenesis, alongside restoration of fission/fusion homeostasis (Drp1, Mfn1/2, Opa1) and PINK1/Parkin-mediated mitophagy. Wavelength specificity has a defined molecular basis: 590 nm modulates VEGF signalling and RPE pump activity, 660 nm interacts with the CuB centre and enhances O₂ binding at CcO, and 850 nm is absorbed by CuA and supports electron entry into complex IV. A second molecular axis is the bidirectional crosstalk between PBM and the circadian system: mitochondrial respiration, ATP turnover and CcO activity oscillate over the 24 h cycle under the control of the BMAL1/CLOCK and PER/CRY core machinery, the NAD⁺/SIRT1–SIRT3 axis and REV-ERBα. Preliminary preclinical and human observations suggest that NIR-induced bioenergetic and functional gains may be coupled to this rhythm, with greater benefit reported when light is delivered in the morning window (≈08:00–11:00); this time dependence should be regarded as an emerging hypothesis rather than an established clinical principle. The clinical evidence is unevenly developed across indications. It is most robust for non-exudative age-related macular degeneration, where multiwavelength PBM (590/660/850 nm; Valeda Light Delivery System) has shown disease-modifying potential in randomized controlled trials (LIGHTSITE I–III and the LIGHTSITE IIIB extension), with sustained BCVA gains and reduced incidence of geographic atrophy over 24 months and beyond. Evidence for retinitis pigmentosa, central serous chorioretinopathy and, with red-light monotherapy, childhood myopia is at present limited to small or short-term studies and remains preliminary. This narrative review synthesizes the molecular machinery engaged by PBM, integrates clinical findings across retinal diseases and discusses how chronotherapeutic delivery of light, aligned with the molecular clock, may further optimize therapeutic efficacy. 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

Microplastics and nanoplastics (MNPLs) are increasingly recognized as dynamic vectors capable of transporting a wide range of environmental contaminants, as well as acting as physical particulates. Their small size, high surface reactivity and strong sorption capacity allow them to carry metals, pesticides, pharmaceuticals and endocrine-active compounds into biological systems. This narrative review examines how these particle-contaminant complexes influence oxidative stress, inflammatory signaling and endocrine function during early development. Relevant literature was identified through structured searches of PubMed, Scopus, Web of Science and Google Scholar, with a focus on the physicochemical properties of plastics, sorption mechanisms, gut barrier physiology and developmental toxicology. Early developmental stages are particularly sensitive, as immature mucus layers, permeable epithelial junctions and underdeveloped detoxification pathways facilitate the uptake and systemic distribution of MNPLs. Once internalized, these particles and their chemical cargo promote the generation of reactive oxygen species through redox-active contaminants, surface-catalysed reactions and mitochondrial dysfunction. The resulting oxidative imbalance activates stress-responsive pathways, including Nrf2–Keap1 signaling, and promotes lipid peroxidation, DNA damage and cellular dysfunction. MNPLs also stimulate inflammatory cascades by activating pattern-recognition receptors, altering cytokine profiles and disrupting epithelial homeostasis. These responses are intensified in the presence of sorbed pollutants, leading to sustained inflammatory states that can be particularly detrimental during organogenesis and immune maturation. Endocrine function is likewise affected, as MNPLs transport hormonally active chemicals and can interfere with hormone-responsive pathways through oxidative and inflammatory mechanisms. These interactions may disrupt thyroid signaling, metabolic regulation and the development of the reproductive axis, with potential long-term physiological consequences. Integrating evidence from polymer chemistry, contaminant behavior and developmental physiology, this review shows that MNPLs act as biologically active vectors that may increase oxidative, inflammatory and endocrine disturbances during early development. These findings highlight the importance of considering particle–contaminant interactions as a critical component of early-life risk assessment. Full article

Zinc (Zn) is an essential trace element that plays important roles in growth, digestion, antioxidant defense, immunity, and inflammation regulation in fish. This study investigated the effects of graded dietary Zn levels on growth performance, serum biochemistry, digestive enzyme activity, zinc transporter expression, antioxidant capacity, immune responses, and inflammatory regulation in juvenile black carp (Mylopharyngodon piceus). Six isonitrogenous and isoenergetic diets were formulated to contain 27.95, 34.38, 44.90, 66.52, 116.14, and 199.56 mg/kg Zn by supplementing ZnSO₄·7H₂O. Juvenile fish with an initial weight of 2.88 ± 0.12 g were fed the experimental diets for 60 days in triplicate tanks. Growth performance increased with dietary Zn and then plateaued at 44.90–199.56 mg/kg; broken-line regression estimated the optimal dietary Zn requirement at 44.6 mg/kg. Adequate Zn supplementation also reduced whole-body lipid content, increased digestive enzyme activities, improved serum HDL-C and ALP levels, and decreased AST and ALT activities. In addition, adequate dietary Zn (44.90 mg/kg) significantly modulated the expression of zinc transporter genes in the liver and intestine. Adequate dietary Zn supplementation enhanced antioxidant capacity by activating the Nrf2/Keap1 signaling pathway, improved intestinal immunity, and strengthened barrier function by increasing the expression of tight junction proteins and mucins. Moreover, adequate dietary Zn could alleviate inflammatory responses by upregulating anti-inflammatory factors and downregulating pro-inflammatory cytokines via the MAPK14 signaling pathway. These findings suggest that dietary zinc at 44.60 mg/kg is sufficient to promote growth, antioxidant status, immune function, and intestinal health in juvenile black carp. Full article

Naturally fermented tofu whey is a nutrient-rich byproduct of tofu production that harbors diverse lactic acid bacteria (LAB) with potential probiotic properties. However, the antioxidant mechanisms of these LAB, particularly the roles of different cellular fractions and their metabolic basis, remain unclear. This study aimed to isolate LAB from naturally fermented tofu whey and evaluate their antioxidant activities across cellular fractions, combining in vitro assays, 16S rDNA-based identification, metabolomic profiling, and cellular validation to elucidate the underlying mechanisms. Six LAB strains were isolated and screened for 2,2-diphenyl-1-picrylhydrazyl and hydroxyl radical scavenging capacity and environmental stress tolerance. Among the identified isolates, Lactiplantibacillus plantarum MCS1903 exhibited the highest extracellular antioxidant activity. Non-targeted metabolomic analysis of cell-free supernatant revealed distinct metabolic profiles compared with the MRS control, with significant enrichment of antioxidant-related metabolites and pathways. In Caco-2 cells, MCS1903 supernatant (<5%, v/v) showed no significant cytotoxicity and effectively alleviated H₂O₂-induced oxidative stress by modulating the Nrf2/Keap1-HO-1 signaling pathway. These findings indicate that tofu whey is a valuable source of functional LAB, and MCS1903 represents a promising candidate for probiotic and functional food applications, supporting the valorization of tofu whey and development of natural antioxidant probiotics derived from fermented food byproducts. Full article

Glaucoma is the leading cause of irreversible blindness worldwide and is characterized by progressive retinal ganglion cell (RGC) loss and optic nerve degeneration. While elevated intraocular pressure (IOP) remains the primary modifiable risk factor, a certain proportion of patients continue to deteriorate despite adequate IOP control, pointing to IOP-independent mechanisms of neurodegeneration. Oxidative stress—defined as an imbalance between the production of reactive oxygen species and the capacity of endogenous antioxidant defenses—has emerged as a central, multi-tiered contributor to glaucoma pathogenesis. In the anterior segment, chronic oxidative damage to the trabecular meshwork impairs aqueous humor outflow and drives IOP elevation. In addition, oxidative stress may impair ocular biomechanical integrity, including corneal hysteresis and lamina cribrosa, resulting in heightened susceptibility to IOP fluctuations. In the posterior segment, oxidative stress directly contributes to mitochondrial damage and vascular endothelial injury, leading to RGC apoptosis. The nuclear factor erythroid 2-related factor 2 (Nrf2)/Kelch-like ECH-associated protein 1 (Keap1) pathway coordinates the principal endogenous antioxidant response, while nicotinamide adenine dinucleotide (NAD⁺) depletion links redox imbalance to metabolic vulnerability of RGCs. This narrative review synthesizes evidence published up to March 2026 on the molecular mechanisms of oxidative stress in glaucoma, the role of biomarkers in aqueous humor and systemic circulation, and the translational landscape of antioxidant-based neuroprotection—including nicotinamide, coenzyme Q10, alpha-lipoic acid, and Nrf2-activating compounds. We highlight gaps between preclinical promise and clinical evidence, and outline priorities for future randomized controlled trials. Full article

Mitochondrial reactive oxygen species (mtROS) are central regulators of cellular function, yet their biological roles are often reduced to an oxidative-stress/antioxidant dichotomy. This review reframes mtROS through the concept of mitohormesis, in which outcomes are neither inherently harmful nor beneficial but are determined by a defined set of contextual variables. We present a mechanistic framework in which mtROS effects depend on chemical species identity, sub-mitochondrial site of production, temporal dynamics, redox-buffering capacity, and metabolic state; together, these variables determine whether mtROS promote adaptive eustress or pathological distress. We then show that, across polyphenols, isothiocyanates, terpenoids, alkaloids, and quinones, the biologically relevant effects of natural redox-modulating compounds are mediated less by direct radical scavenging than by pro-hormetic mechanisms, including mild electron transport chain perturbation, nuclear factor erythroid 2-related factor 2/Kelch-like ECH-associated protein 1 (NRF2/KEAP1) activation, modulation of mitochondrial membrane potential, mitochondrial quality control, and NAD⁺/NADPH regulation. Applying this framework to disease reveals strong tissue and state dependence: neurodegeneration favors buffering expansion and mitophagy; metabolic disease may benefit from exercise-mimetic and NRF2-activating strategies; cardiovascular disease illustrates mitohormesis through ischemic preconditioning and CoQ10 supplementation; and cancer requires distinction between prevention and therapy because redox buffering can either protect normal tissue or support tumor survival. Finally, we argue that the failure of non-specific antioxidant supplementation is mechanistically predictable and propose context-aware, biomarker-guided, temporally optimized, and compartment-targeted redox interventions as a more rational translational path. Full article