Search Results (1,207)

Conventional hormonal and clinical models inadequately clarify the complex and diverse aspects of female infertility, resulting in poor reproductive outcomes and reduced egg viability. A growing body of research indicates that female reproductive failure is mostly due to disruptions in cellular homeostasis, especially concerning organelle quality control. Oxidative stress has emerged as a crucial mediator connecting metabolic, inflammatory, and ageing-related processes to ovarian failure, however its downstream impacts on intracellular organelle turnover remain insufficiently clarified. Our narrative review encapsulates the existing data for a unified pathogenic concept focused on the redox-regulated mitochondria–lysosome axis. We examine the interaction of oxidative stress, mitochondrial malfunction, compromised mitophagy, and lysosomal deficiency in granulosa cells and oocytes. Prolonged oxidative stress may disrupt this equilibrium, leading to defective mitochondria accumulation and impaired mitophagy. This self-perpetuating cycle may ultimately jeopardises reproductive viability and oocyte integrity. The integrated axis offers a shared molecular foundation for various infertility-related diseases, such as inadequate ovarian response, obesity-associated infertility, polycystic ovary syndrome, and ovarian ageing. Ultimately, we analyse new findings suggesting that specific antioxidant chemicals modify mitophagy and lysosomal function while also neutralising reactive oxygen species, highlighting their potential use in precision fertility treatments. Our research redefines female infertility as a condition of redox-dependent organelle quality control, thereby introducing novel avenues for identifying biomarkers, categorising patients, and targeting treatments in assisted reproduction. Full article

Glial cells, particularly astrocytes and microglia, are central to maintaining CNS homeostasis and coordinating responses to injury through tightly regulated metabolic, inflammatory, and mechanosensitive processes. Emerging evidence identifies the Hippo signaling pathway and its downstream effectors YAP/TAZ as key regulators of glial functions, influencing proliferation, polarization, intercellular communication, and the balance between neuroprotection and neurotoxicity. This review discusses the Hippo signaling pathway and its transcriptional co-activators YAP/TAZ as context-dependent hubs integrating mechanical, metabolic, and immune cues in astrocytes and microglia. Particular attention is given to MST1/2- and YAP/TAZ-dependent signaling in microglia, which governs inflammatory states, redox balance, mitophagy, and mechanosensing. In astrocytes, Hippo–YAP signaling emerges as a bidirectional regulator of reactive gliosis and neuroprotection, capable of constraining excessive scar formation. However, when chronically suppressed, it impairs glutamate clearance, metabolic support, and resistance to neurodegeneration. Disruption of Hippo signaling in glial tumors is also considered, with YAP/TAZ–TEAD complexes driving glioblastoma stemness, infiltrative growth, immune evasion, and therapy resistance. Finally, therapeutic perspectives are outlined that emphasize context-selective modulation of Hippo signaling in the CNS. Overall, Hippo–YAP/TAZ signaling is presented as a highly context-dependent regulator at the interface of glial inflammation, neurodegeneration, and glioma biology and as a promising but demanding target for future CNS therapies. Full article

Exercise adaptation depends on overload that is resolved by recovery, yet the same biology becomes maladaptive when immune, endocrine, metabolic, and muscle-centered stress signals fail to normalize. Exercise-induced maladaptation represents a systems-level failure of biological resolution, with direct relevance to disease-like dysregulation. Functional overreaching, non-functional overreaching, and overtraining syndrome remain difficult to diagnose because no single biomarker provides adequate specificity, temporal stability, or clinical portability. This narrative review synthesizes human and mechanistic evidence across proteomics, transcriptomics, metabolomics, endocrine profiling, extracellular vesicles, and mitochondrial quality-control biology to define the molecular architecture most relevant to athlete monitoring. Across these layers, the most coherent signatures cluster in immune-acute-phase activation, redox-buffering strain, endocrine drift, altered substrate availability, excitation–contraction dysfunction, integrated stress-response signaling, and defects in autophagy–mitophagy and lysosomal remodeling. Three translational elements emerge from this synthesis: a systems-convergence model of recovery failure, a staged biomarker deployment hierarchy, and a provisional recovery failure index. The practical priority is therefore not a solitary marker, but serial phenotype-anchored multimarker panels that connect circulating signals with muscle-centered biology and support decision-making before prolonged recovery failure becomes entrenched. Full article

Liver diseases, including fatty liver, hepatitis, and cirrhosis, remain major global health challenges due to their disruption of metabolic homeostasis and detoxification processes. Redox imbalance plays a central role in liver disease progression by promoting inflammation, hepatic stellate cell activation, mitochondrial dysfunction, and fibrogenesis. Although flavonoids have historically been considered direct reactive oxygen species (ROS) scavengers, emerging evidence indicates that their biological effect at physiological concentrations are primarily mediated through modulation of intracellular redox signalling rather than simple radical neutralisation. This review highlights flavonoids as redox-modulating agents capable of restoring hepatic redox homeostasis through coordinated regulation of molecular pathways. Mechanistically, flavonoids activate the Nrf2-Keap1 axis to enhance endogenous antioxidant defences, including heme oxygenase-1 and glutathione biosynthesis enzyme, while suppressing NF-κB-mediated pro-inflammatory signalling and modulating MAPK and PI3K/Akt pathways. They also regulate mitochondrial redox balance, supporting mitophagy, metabolic adaptation, and cellular resilience to oxidative stress. In addition, flavonoid biotransformation by the gut microbiome improves intestinal barrier integrity, reduces endotoxin-driven hepatic inflammation, and contributes to gut–liver crosstalk. Collectively, these mechanisms position dietary flavonoids as multi-target redox modulators with promising therapeutic potential in chronic liver disease, although further studies are needed to improve their bioavailability and clinical translation. Full article

Beyond their classical role as “cellular powerhouses”, mitochondria are increasingly recognized as dynamic and interconnected networks whose architecture, quality control, and intercellular communication influence cellular and organismal homeostasis. Mitochondrial dynamics—including fusion–fission balance, mitophagy–biogenesis coupling, intracellular organization, and intercellular transfer via tunneling nanotubes, extracellular vesicles, or transient cell fusion—contribute to tissue adaptation and functional decline during aging. Focusing on cardiac muscle, skeletal muscle, and the nervous system, this narrative review synthesizes current evidence describing how aging disrupts mitochondrial network integrity through altered dynamics, impaired organelle positioning and transport, reduced mitophagy, mtDNA instability, and compromised metabolic coupling between cells. These alterations propagate across tissues, limiting energetic flexibility, stress resilience, and regenerative capacity. Building on these mechanisms, we discuss a systems-level perspective in which aging is associated with progressive loss of mitochondrial network coherence rather than solely cumulative molecular damage. Within this framework, mitochondrial connectivity functions as an integrative descriptor of cellular resilience: well-organized networks counteract metabolic perturbations, whereas functionally decoupled networks amplify stress and promote maladaptive aging trajectories. Emerging evidence indicates that physiological and pharmacological interventions, including endurance exercise, caloric restriction or mimetics, fusion-supporting pathways, and mitophagy-enhancing strategies, can partially restore network organization even later in life. Molecular, cellular, and tissue-level insights are integrated to highlight mitochondrial network dynamics as both a mechanistic contributor to aging and a potentially modifiable target for future preventive and therapeutic interventions. Full article

Oleanolic acid (OA) is a hydrophobic pentacyclic triterpene widely distributed in the plant kingdom and characterized by broad biological activity, including antioxidant, anti-inflammatory, neuroprotective, renoprotective, and anticancer effects. Increasing evidence suggests, however, that many of these actions are better explained not by single molecular targets, but by OA-dependent modulation of an integrated organelle stress network involving mitochondria, the endoplasmic reticulum (ER), autophagy, mitophagy, and apoptosis. This review critically analyzes the available evidence on the effects of OA on the mitochondria–ER–autophagy–apoptosis axis, with particular emphasis on mechanisms governing the transition between cellular adaptation and cell death. The available literature indicates that, in non-cancer models, OA most commonly lowers reactive oxygen species (ROS), stabilizes mitochondrial function, attenuates the ER stress signature, and promotes adaptive autophagy and mitophagy. In contrast, in many cancer models, OA may enhance mitochondrial dysfunction, lower the threshold for mitochondrial apoptosis, and induce autophagy that can be either protective or cytotoxic depending on the biological context. Overall, the current evidence supports a model in which OA acts as a context-dependent modulator of the organelle stress threshold, shifting the balance of an integrated mitochondria–ER–autophagy–apoptosis network rather than functioning as a uniformly cytoprotective or uniformly proapoptotic compound. At the same time, the literature remains heterogeneous with respect to models, doses, exposure times, and markers used, while poor aqueous solubility and limited bioavailability continue to constrain translation. Future studies should therefore integrate analyses of mitochondria, ER, mitochondria–ER contact sites (MERCS), autophagy, apoptosis, pharmacokinetics, formulation, and safety in order to define the true potential of OA as a modulator of biological stress. Full article

Silymarin (Silybum marianum (L.) Gaertn. extract) is a widely used botanical for liver disease, yet clinical results remain inconsistent. Most mechanistic work uses supraphysiological aglycones, whereas humans are exposed predominantly to phase II conjugates that are strongly protein-bound and routed by transporters toward bile and the intestinal mucosa. We reframe silymarin activity through a spatial pharmacology lens, proposing three post-intake windows: early (0–2 h) conjugate-dominant exposure with localised β-glucuronidase-mediated reactivation; intermediate (2–8 h) enterohepatic recirculation pulses; and late (8–48 h) microbial catabolite contributions. Each window engages distinct signalling modules—Keap1/NRF2, NF-κB, and AMPK-mTOR-TFEB—via transient redox events (quinone cycling, micro-H₂O₂ relays) and proteostatic remodelling (autophagy/mitophagy). We synthesise human pharmacokinetic and clinical evidence—with emphasis on MASLD and alcohol-associated liver disease—and show how formulation, meal timing, and microbiome metabotype determine which windows are engaged. Finally, we propose minimum reporting standards and falsifiable hypotheses to reduce between-study heterogeneity and enable precision use of silymarin. Full article

Background: Circadian disruption exacerbates type 2 diabetes mellitus (T2DM). Time-restricted feeding (TRF) and exercise (EX) improve metabolic health, but their combinatory effect remains unclear. This study investigated whether combined TRF and EX additively ameliorates metabolism via circadian reprogramming in db/db mice. Methods: Eight-week-old male db/db mice were assigned to control (Con), diabetic model (DM), TRF (8 h feeding window), EX (treadmill, 60 min/day, 5 days/week), or combined TRF + EX groups for 8 weeks (n = 8/group). Body weight, glucose/insulin tolerance, and 24 h energy metabolism (CLAMS) were assessed. Mitochondrial function, oxidative stress, inflammation, and expression of mitophagy (Pink1, Park2, Bnip3, Fundc1) and thermogenic (Ucp1, Pgc1a, Prdm16, Cidea) genes were measured. Results: Compared with the con group, DM mice showed obesity, hyperglycemia and blunted circadian metabolic rhythm. The TRF and EX groups improved these defects. Specifically, combined TRF + EX reduced fasting blood glucose from 25.3 ± 3.1 mmol/L (DM) to 13.2 ± 1.8 mmol/L (p < 0.05), body weight from 49.8 ± 2.5 g to 39.5 ± 1.7 g (p< 0.05), and body fat percentage from 45.6 ± 3.2% to 32.1 ± 2.2% (p < 0.05). GTT area under the curve (AUC) decreased from 3711.0 ± 186.5 (DM) to 2118.0 ± 112.4 (p < 0.05), and ITT AUC decreased from 2617.5 ± 135.8 to 1260.0 ± 68.9 (p < 0.05). Notably, the combination of TRF + EX produced greater effects than either intervention alone: body weight, fasting blood glucose, and glucose/insulin tolerance were greatly improved (p < 0.05). In addition, compared with the DM group, the diurnal metabolic amplitude and phase were improved in the TRF or EX group; the combination group showed further improvements in these parameters. Furthermore, TRF and EX each resulted in significantly higher expression of key thermogenic genes (Ucp1, Pgc1a, Prdm16, Cidea) in white adipose tissue (WAT) and brown adipose tissue (BAT) (p < 0.05), and the TRF + EX group showed the highest expression levels. Combined intervention also restored skeletal muscle SOD activity (31.2 ± 2.9 U/mg prot vs. DM 20.1 ± 2.5 U/mg prot, p < 0.05) and reduced serum TNF-α (28.5 ± 4.5 pg/mL vs. DM 65.8 ± 8.5 pg/mL, p < 0.05) and IL-6 (21.6 ± 3.8 pg/mL vs. DM 50.3 ± 7.1 pg/mL, p < 0.05). Conclusions: TRF + EX additively restores metabolic homeostasis in diabetes by re-entraining circadian energy rhythms, improving mitochondrial quality, and activating adipose thermogenesis, supporting further investigation of integrated lifestyle timing as a potential therapeutic strategy. Full article

Primary Sjögren’s disease (SjD) is characterized by lymphocyte infiltration into exocrine glands. Mitochondrial dysfunction is a critical pathological mechanism underlying SjD, and mitophagy plays a vital role in clearing damaged mitochondria. This study used bioinformatic analysis to explore the potential roles of mitophagy-related genes in SjD pathogenesis and immune infiltration. Bioinformatic analysis was performed on the SjD microarray datasets to identify differentially expressed genes (DEGs). Mitophagy-related DEGs were selected and analyzed using functional enrichment, protein–protein interaction (PPI) networks, and machine learning (Least Absolute Shrinkage and Selection Operator [LASSO] and Random Forest) to identify hub genes. Their diagnostic value was assessed by receiver operating characteristic (ROC) curves. Immune infiltration and its correlation with hub genes were also evaluated. Hub gene expression in the salivary glands of patients was validated using qRT-PCR. Regulatory networks were also predicted. Three hub genes (GABARAPL1, PINK1, and SQSTM1) were identified. They showed high diagnostic specificity and were downregulated in SjD salivary glands. Immune infiltration analysis revealed increased levels of activated natural killer (NK) cells, memory B cells, plasma cells, CD8+ T cells, Tfh cells, and M1 macrophages, but decreased levels of Tregs and M2 macrophages. Hub gene expression was correlated with specific immune cell subsets. Regulatory network predictions highlighted potential upstream regulators and therapeutic compounds. This study identified three mitophagy-related hub genes linked to immune dysregulation in SjD, providing novel insights into disease mechanisms and potential therapeutic targets. Full article

Gaucher disease (GD) is characterized by the accumulation of glucosylceramide within lysosomes due to mutations in the GBA1 gene, which encodes the enzyme glucocerebrosidase. Current treatments are ineffective for patients suffering from severe neuronopathic forms of the disease. In this context, new therapeutic approaches for neuronopathic GD forms are needed. Lysosomal and mitochondrial dysfunction associated with increased oxidative stress and disturbances in the autophagic process have been described in GD. Here, we address c-Abl-RIPK3 signaling and its contribution to the accumulation of dysfunctional mitochondria in GD. Fibroblasts from patients with GBA1 mutations and neurons treated with the glucocerebrosidase inhibitor CBE exhibited alterations in the ΔΨm and mitochondrial morphology, as well as reduced capacity to form autophagosomes. Pharmacological inhibition of c-Abl or RIPK3 restored mitochondrial function and promoted autophagosome formation, along with an increase in autophagic engulfment of mitochondria in both GD models. In conclusion, the c-Abl-RIPK3 signaling pathway contributes to mitochondrial dysfunction and blockade of autophagy components in the mitochondria, both of which are altered in the neuronopathic forms of GD. Full article

Halogenated derivatives of polycyclic aromatic hydrocarbons (PAHs), such as chlorinated PAHs (ClPAHs), are an emerging class of contaminants that are being detected in the environment as well as in wildlife and human populations. Previous studies have shown that chemical substitution of PAHs, including chlorination, may alter the toxicity of parent PAHs; however, whether chlorination affects their endocrine-disrupting potential remains unexplored. In this study, we examined the effects of phenanthrene (Phe), one of the most prevalent PAHs, and its chlorinated congeners, 9-chlorophenanthrene (9ClPhe) and 9,10-dichlorophenanthrene (9,10Cl₂Phe), on hormone production in granulosa cells, key hormone-secreting cells of the ovary. We observed that Phe and its chlorinated congeners differentially altered anti-Müllerian hormone (AMH), estradiol (E2), and progesterone (P4) secretion. Since mitochondria are central to steroidogenesis, we further evaluated mitochondrial function. While Phe increased ATP production, both 9ClPhe and 9,10Cl₂Phe increased ROS, decreased mitochondrial membrane potential, and reduced the expression of markers for mitochondrial dynamics and mitophagy without altering ATP levels. We further tested impacts on cell fate and found that neither Phe nor its chlorinated congeners altered granulosa cell apoptosis. Together, these results suggest that chlorination of Phe leads to dose-dependent, differential effects on hormone production and mitochondrial pathways without inducing cell death in granulosa cells. This study highlights the potential adverse impacts of ClPAH exposure on ovarian follicle development and female fertility by disrupting steroidogenesis and mitochondrial quality control. Full article

Adenine nucleotide translocase (ANT) has traditionally been defined as the ADP/ATP exchanger of the inner mitochondrial membrane. However, accumulating mechanistic evidence reveals a substantially broader functional spectrum that extends beyond nucleotide transport. In this review, we integrate these advances into a unified conceptual framework that positions ANT isoforms as modulators of mitochondrial bioenergetics, quality control, and cellular communication. Beyond its canonical exchange activity, ANT influences permeability transition thresholds and membrane potential stability, participates in regulated uncoupling and redox control, and contributes to inner membrane organization and cristae integrity. ANT further modulates TIMM23-dependent protein import and PINK1–Parkin-mediated mitophagy, thereby shaping mitochondrial quality control decisions. In addition, ANT regulates mitochondrial nucleic acid release and inflammasome activation, linking bioenergetic imbalance to innate immune signaling. Emerging evidence for alternative subcellular localizations suggests that ANT-dependent signaling extends mitochondrial state information to extracellular and intercellular contexts. Collectively, these findings support an expanded view of ANT as a multifunctional modulator linking mitochondrial energetic state to stress adaptation, inflammatory signaling, and tissue-level communication. Full article

Severe burn injury results in systemic inflammation, edema, multiple organ disorder and muscle wasting. These events are provoked by the massive dysfunction of mitochondria not only in the burned skin but also in muscles and internal organs, which is induced by the release of damage-associated molecular patterns and catecholamines. Dysfunctional mitochondria are characterized by increased ROS production and the release of mitochondrial DNA, which lead to enhanced expression of proinflammatory cytokines. Mitochondria present a key target for treatment of severe burns, and various pharmacological approaches are being developed to protect normal mitochondrial functions after burn injury. Full article

Aging is associated with disturbances in brain energy metabolism, mitochondrial dysfunction, and increased oxidative stress, all of which increase neuronal vulnerability and contribute to the development of neurodegenerative disorders. Growing evidence indicates that physical exercise exerts neuroprotective effects through the release of exerkines–exercise-induced signaling molecules that mediate communication between peripheral tissues and the brain. Among them, irisin, a proteolytic cleavage product of the membrane protein FNDC5, has emerged as an important mediator of the muscle–brain axis. This review summarizes current knowledge on the molecular mechanisms underlying irisin activity in the central nervous system, with particular emphasis on the AMPK–PGC-1α–FNDC5/BDNF signaling axis, rapid receptor-mediated pathways involving the cAMP/PKA/CREB and ERK/CREB cascades, and the regulation of mitochondrial homeostasis, including biogenesis, dynamics, autophagy, and mitophagy. Experimental studies suggest that irisin may improve neuroplasticity, neuronal survival, mitochondrial function, and reduce oxidative stress, thereby alleviating cognitive deficits in models of aging and neurodegeneration. Although the precise receptor mechanisms and intracellular signaling events remain incompletely understood, accumulating evidence identifies irisin as a promising therapeutic target linking metabolic adaptation with neuroprotection. Further investigation of irisin-dependent pathways may facilitate the development of novel strategies aimed at preserving brain function and delaying the progression of age-related neurodegenerative diseases. Full article

Autophagy-mitophagy pathways are essential for regulating immune homeostasis. However, their contribution to population-level chronic low-grade systemic inflammation (SI) remains unclear. The objective was to investigate the association between variation in the genes related to the autophagy-mitophagy pathways and SI, and to examine whether lifestyle factors modify this relationship. We conducted genome-wide association studies and gene-set enrichment analyses using data from the Korean Genome and Epidemiology Study (KoGES, n = 28,102) and UK Biobank (UKBB, n = 343,892). SI was defined as an elevated white blood cell count or high-sensitivity C-reactive protein. Using Core Longevity State Vectors (CLSVs)—gene sets representing immune-longevity pathways derived from comparative transcriptomic analysis—we tested six pathways and constructed a weighted genetic risk score (GRS) from significant variants. Gene–lifestyle interactions were examined with respect to major dietary and lifestyle factors. Among six CLSVs, only CLSV-2 (mitophagy and autophagy) showed a significant association with SI (β = 0.425, p = 0.008). Six single nucleotide polymorphisms (SNPs) in autophagy-mitophagy genes (INPP5D, ATG16L1, ATG7, AP3S1, OPTN, and VPS33A) were associated with SI in KoGES (p < 5 × 10⁻⁵), and ten SNPs (genes selected in KoGES plus RAB7A, ATG12, VPS33A, BECN1) reached genome-wide significance in UKBB (p < 5 × 10⁻⁸). A higher GRS was associated with increased SI in both cohorts and was strongly associated with metabolic syndrome (MetS, OR = 1.91 in KoGES; OR = 1.62 in UKBB). SI was characterized by neutrophilia with relative lymphopenia. In UKBB, significant gene–lifestyle interactions were observed for diet, physical activity, smoking, and alcohol (p < 0.01). Favorable lifestyle factors reduced SI most effectively in individuals with protective genotypes. Among individuals with a high vegetable/fruit intake, SI prevalence was 35%, 36%, and 38% in the negative-, zero-, and positive-GRS groups, respectively, compared with 36%, 45%, and 48% in the low-intake groups. In conclusion, genetic variations in autophagy-mitophagy pathways specifically influence SI. Genetic predisposition substantially modifies the benefits of lifestyle, underscoring the importance of integrating genetic and lifestyle factors in understanding SI susceptibility. Full article