Longevity Papers

The global population is rapidly aging, leading to a significant increase in age-related diseases in the coming years. Muscle dysfunction is a prevalent chronic condition among older adults, posing significant public health challenges. One of the key age-related changes in muscle tissue is the accumulation of advanced glycation end products (AGEs). Previous studies have reported that AGEs are highly associated with muscle dysfunction, particularly in diabetes. However, the relationship between AGEs and muscle aging still remains to be clarified. This study aimed to investigate the effects of AGEs on muscle repair function and regeneration through cellular and senescence/aging animal models. In cell model, the non-cytotoxic concentrations of AGEs induced cell senescence and inhibited myogenic differentiation in C2C12 myoblasts, as evidenced by senescence-associated β-galactosidase staining and hematoxylin and eosin (H&E) staining. These effects by AGEs could be restored by the treatment of neutralized antibody for receptor for AGEs (RAGE). In a d-galactose-accelerated senescence/aging mouse model, the immunohistochemistry staining showed a substantial AGEs accumulation and RAGE expression in the muscles, which could be reversed by AGEs inhibitor aminoguanidine treatment. In a model of muscle regeneration by glycerol injection in the tibialis anterior muscle, the muscle regeneration/repair capacity was significantly impaired and the Pax7 and MyoD expression was reduced in aging mice, which could also be reversed by aminoguanidine treatment. These findings suggest that AGEs-RAGE axis promote myoblast senescence, inhibit their differentiation, and it may impair muscle repair capacity in aging animals. Further research is needed to elucidate the underlying mechanisms.

Age-related macular degeneration (AMD) is a leading cause of blindness in older adults, with oxidative stress as a central driver. We proposed the Antioxidant Vitamin Index (AVI), a composite indicator integrating vitamins A, C, and E to quantify systemic antioxidant nutritional status, and evaluated its association with AMD across three large cohorts: the UK Biobank, NHANES 2005-2008, and a Tianjin clinical cohort. Using Cox proportional hazards models for incident AMD in the UK Biobank and multivariable logistic regression for AMD prevalence in NHANES and Tianjin, complemented by restricted cubic splines, quartile analyses, and machine learning, we consistently observed that higher AVI was independently associated with a lower risk of AMD. Dose-response analyses showed a progressive decline in AMD risk with increasing AVI, and model performance improved when AVI was added to conventional risk factors. Machine learning and SHAP interpretation further identified age and AVI as dominant predictors of AMD. These findings support AVI as a biologically grounded, quantifiable metric with potential for early screening, risk stratification, and nutrition-based prevention of AMD.

Age-related hearing loss is a prevalent and growing public health issue among the elderly. Here, we perform a multi-ancestry genome-wide association study comprising 456,613 cases and 1,053,834 controls, identifying 140 independent loci associated with age-related hearing loss, including 44 novel signals. We further fine-map 9 likely causal missense variants for age-related hearing loss and provide evidence of purifying selection for age-related hearing loss-associated variants. Notably, genetic risk for age-related hearing loss is strongly correlated with behavior traits such as neuroticism score and irritability. Integration of molecular phenotypes identifies 22 genes and 85 DNA methylation sites significantly associated with age-related hearing loss. Moreover, analyses incorporating spatial and single-cell transcriptomic identify the inner ear as a crucial site of age-related hearing loss, emphasizing the importance of hair cells, supporting cells, basal and root cells of the stria vascularis to its pathogenesis. Our study provides genetic and cellular insights into age-related hearing loss and advance our understanding of its genetics architecture.

The therapeutic efficacy of extracellular vesicles (EVs) depends on the status of their donor cells. Cellular senescence of bone marrow mesenchymal stem cells (BMSCs), which induces significant changes to cellular secretome, greatly affects the osteogenesis of the donor BMSCs along with BMSC-derived EVs. Stem cells prefer a homeostatic self-renewing state to alleviate the senescence and loss of stemness caused by external disturbance, but which inevitable in EV produce. In this study, to avoid the senescence of BMSCs caused by in vitro culture and boost the osteogenesis efficacy of BMSC-derived small extracellular vesicles (sEVs), we established a niche-mimicking (NM) culturing system to maintain the cellular homeostasis that significantly delayed stem cell senescence in vitro. As a result, single cell transcriptome revealed that NM-culturing significantly enhanced the expression level of the homeostasis-related genes. Then we found that sEVs produced by homeostatic BMSCs exhibited superior osteogenic stimulation efficacy and bone defect repair compared to those from conventional monolayer-cultured BMSCs. Mechanically, by analyzing the "shuttling effect" of sEVs via multi-omic analysis, we found that the key homeostasis-related genes (including JMJD6, LIF, CYP19A1, and LAMA1) functioned throughout the entire process, by thus we defined the "homeostatic phenotype" of BMSC. Among the identified homeostasis-related genes in sEVs, JMJD6 emerges as a key gene, exhibiting anti-senescence characteristics and stimulating osteogenesis via Wnt pathway in BMSCs. This study optimizes the production part of stem cell-based EV therapy by maintaining the cellular homeostasis of donor cells, which delays cell senescence and boosts the osteogenesis stimulation of EVs, and JMJD6 is a key homeostasis-related gene that regulated cell senescence and osteogenesis of BMSC.

Physiological and pathological changes associated with aging contribute to deteriorating disease prognosis in sepsis. However, the mechanisms by which these disturbances exacerbate inflammation remain underexplored. In this study, fecal samples were collected from aged and young septic patients and mice and subsequently transplanted into young pseudo-germ-free mice via fecal microbiota transplantation. Fecal, colon tissue, and blood samples were collected to be used 16S rDNA sequencing to characterize the gut microbiota, histopathological examination, enzyme-linked immunosorbent assay and FITC-dextran intestinal permeability assay to assess gut injury and gut barrier function. Additionally, nontargeted and targeted metabolomics were used to identify differential metabolites in the feces of aged and young septic mice. To further validate the roles of specific bacterial strains and their metabolites in sepsis, genetically engineered bacteria were used in both

Estimating brain age, a promising biomarker for evaluating brain health, continues to present significant challenges in terms of accuracy. This study investigates the potential of multi-time scale dynamic effective brain networks (MTS-DEBN) to enhance the prediction of brain age and to identify atypical aging patterns associated with major depressive disorder (MDD) using resting-state functional magnetic resonance imaging (rs-fMRI).

Aging is characterized by progressive cellular dysfunction and increased susceptibility to chronic diseases. Enhancing autophagy, a key cellular clearance process, offers a promising strategy to combat aging. In this study, we investigated the autophagy-inducing and anti-aging properties of Salvia plebeia R. Br. ethanol extract (SPE) using in vitro and in vivo models. Our results showed that SPE enhanced autophagosome and autolysosome formation, elevated LC3-II and Beclin-1 levels, and reduced p62 expression in human foreskin fibroblasts (HFFs), confirming its autophagy-inducing activity. SPE also mitigated d-galactose (d-gal)-induced cellular senescence, reducing senescence-associated beta-galactosidase (SA-β-gal) staining, senescence markers (p16, p21), senescence-associated secretory phenotype (SASP) factors, and γ-H2AX foci. These effects were Atg7-dependent, as Atg7 knockout abolished the benefits, highlighting autophagy's role in SPE's action. In vivo, SPE improved physical function, reversed cellular senescence, enhanced antioxidant defenses, and restored autophagic activity in d-gal-induced prematurely senescent mice. Furthermore, SPE alleviated age-related cognitive decline, reduced neuronal damage, increased synaptic density, and mitigated tau accumulation. Notably, SPE demonstrated good tolerability over 12 weeks, with stable body weight, no apparent tissue injury, and unchanged serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), and creatinine. Chemical profiling identified rosmarinic acid (RA) as a major bioactive constituent that recapitulated key autophagy- and senescence-related effects in vitro. These findings suggest that SPE is a promising natural autophagy enhancer with potential to promote healthy aging, combat age-related diseases, and serve as a novel therapeutic strategy for cellular dysfunction in aging.

Cellular senescence is the core cytological basis for organismal aging and the development of age-related diseases. Accumulating evidence indicates that senescent phenotypes can be maintained long-term even after the removal of senescence-inducing stressors, and may even affect daughter cells and offspring. This review systematically proposes an integrated theoretical framework of "aging metabolic memory", explaining the persistence, transmissibility, and potential heritability of aging from a systems biology perspective. First, it elaborates on how mitochondrial metabolic reprogramming reshapes the cellular epigenetic landscape (DNA methylation, histone modification) by altering the homeodynamics of key metabolites (NAD⁺, α-ketoglutarate, succinate, etc.), thereby forming stable senescence imprints; second, it in-depth analyzes the mechanisms by which the senescence-associated secretory phenotype (SASP) and extracellular vesicles (EVs) act as "memory carriers" to achieve intercellular transmission and systemic spread of senescent phenotypes; on this basis, combined with the latest progress in epigenetics, it proposes and demonstrates a hypothetical model for the transgenerational transmission of aging metabolic memory through germ cells, exploring its biological significance and evolutionary implications; finally, it systematically sorts out and prospects novel aging intervention strategies based on "memory intervention" (rather than mere elimination), including metabolic resetting, epigenetic remodeling, transmission blocking, and germ cell-targeted intervention. This review summarizes the spatiotemporal dynamic characteristics of aging and may provide multi-dimensional intervention pathways for the precise prevention and treatment of age-related diseases and the promotion of healthy aging.

Ageing is the primary non-modifiable risk factor for cardiovascular diseases (CVDs), with older women facing a greater risk of CVDs than age-matched men. Vascular smooth muscle cells (VSMCs) dysfunction and impaired calcium (Ca

The knock-out mutation of the unique M13 family member, the Drosophila melanogaster (fruit fly) Neprilysin-like 15 (Nepl15), resulted in marked reductions of glycogen and glycerolipid storage in adult male flies, but a significant increase of glycogen storage in adult female flies, although the mutant flies consumed the same amount of food as the isogenic w1118 controls. The findings prompted us to characterize sex and age-specific effects of Nepl15 knock-out (Nepl15KO) mutation on lifespan, fertility and fecundity, physiology, cytophysiology, and overall health. The current study shows Nepl15 transcripts are expressed in all embryonic stages of the control flies. The mutant embryos show more glycogen storage, likely due to more maternal glycogen deposition in the eggs. Moreover, there are slight increases in the number of eggs laid, the percentage of pupariation, and the percentage of adult fly eclosion from pupae in the Nepl15KO mutant flies. Interestingly, Nepl15KO female, but not male flies, outlive the respective control flies when cultured on a standard diet. The mutant adult females show significantly less Target of Rapamycin (TOR) and more Sirtuin 6 (Sirt6) expression, changes that may synergistically contribute to their lifespan extension. In contrast, mutant males exhibit significant reductions in both TOR and Sirt6 expression, potentially offsetting their effects on longevity. Cellular health is further improved in mutant females, as evidenced by a marked reduction in reactive oxygen species (ROS), associated with a 1.5-fold increase in the Superoxide dismutase 2 (Sod2) expression at 7 days of age. Both sexes demonstrate improved gut barrier integrity at 40 days, with reduced Smurf leakage compared to age-matched controls. Optical cardiography reveals that heart rate in 40-day-old mutants is better preserved, resembling that of 7-day-old flies, whereas control flies show a pronounced age-associated decline. Functionally, Nepl15KO males and females outperform controls in a 6-cm climbing assay at 10, 20, 30, and 40 days of age, with the greatest difference observed at day 40. Following a 45-minute exercise bout at 10 rpm, mutant females continue to outperform controls at both 7 and 40 days, indicating preserved neuromuscular performance. Consistently, ATP levels are significantly elevated in 7- and 40-day-old mutant females, but not in mutant males. Interestingly, only 7-day-old mutant males exhibit increased mitochondrial inner membrane potential, which may enable more rapid ATP turnover when energy demand arises. No detectable differences are observed in thoracic muscle or mitochondrial ultrastructure, nor in overall mitochondrial number. However, no observable changes are noticed in the ultrastructure of the thoracic muscle and mitochondria, and the overall number of mitochondria in the mutant flies. Collectively, our findings demonstrate that Nepl15 loss-of-function confers health benefits at cellular, organ, and organismal levels, with pronounced sex-specific differences. However, the mechanisms by which aging mutant males sustain enhanced functional performance remain elusive.

Neurodegenerative disorders are an Critical worldwide issue, characterized by progressive neuronal loss and cognitive decline with limited effective therapies. A central problem in these conditions is chronic neuroinflammation, oxidative stress, and disrupted cellular homeostasis. Polyamines, such as putrescine, spermidine, and spermine-small molecules-play vital roles in maintaining neuronal function, regulating autophagy, and protecting against cellular stress. Notably, spermidine-induced autophagy has emerged as a key mechanism linking polyamine metabolism to neuronal longevity and cognitive resilience. Recent studies highlight that probiotics and specific gut microbes can effectively modulate host polyamine production through the gut-brain axis, influencing neural health. This microbial modulation has been shown to restore polyamine balance, enhance antioxidant defenses, and reduce neuroinflammatory responses. Targeting microbiota-driven polyamine synthesis is emerging as a promising, non-invasive approach for neuroprotection. This review consolidates the current understanding of polyamine biology and microbial influences, highlighting their therapeutic potential. Exploring these interactions offers new avenues for innovation in combatting neurodegenerative disorders.

Cardiovascular diseases remain the leading cause of global mortality. Cellular senescence has recently been implicated in the pathogenesis of various cardiovascular diseases. Our group has previously shown that the matricellular protein CCN5 is a potent anti-fibrotic molecule capable of inhibiting and reversing cardiac fibrosis. In this study, we investigated whether CCN5 can modulate cellular senescence in the heart utilizing three readouts: western blotting for p53 and p21, staining for senescence-associated β-galactosidase, and microscopic analysis of γH2AX-foci. CCN5 effectively inhibited doxorubicin-induced cellular senescence in both H9c2 cardiac myoblasts and fibroblasts. In addition, CCN5 suppressed cellular senescence in H9c2 cardiac myoblasts induced by the senescence-associated secretory phenotype factors secreted from cardiac fibroblast, and vice versa. CCN5 also restored the apoptotic response of senescent cells. Finally, CCN5 attenuated myocardial infarction-induced cellular senescence in mice. Collectively, our findings provide novel insights into the potential role of CCN5 in the development of anti-senescence therapies.

Skin aging is driven by both extrinsic factors, such as ultraviolet exposure, and intrinsic, chronological processes that lead to progressive deterioration in skin homeostasis and structure. Chronological aging is associated with replicative senescence and a range of molecular and cellular alterations, including genomic instability, mitochondrial dysfunction, and impaired intercellular communication. The dynamic cross-talk between dermal fibroblasts and epidermal keratinocytes is crucial for maintaining skin integrity throughout aging, with extracellular vesicles (EVs) emerging as key mediators of this intercellular communication. While the impact of keratinocyte-derived EVs in modulating dermal fibroblast function is increasingly recognized, the reciprocal influence of fibroblast-derived EVs on keratinocytes remains largely unexplored, particularly in the context of aging. In this study, we isolated and characterized small EVs, mainly exosomes, from primary human dermal fibroblasts derived from young and aged donors. We analyzed their size, molecular composition, and age-related differences, and assessed their effects on keratinocyte function. While small EVs treatment had limited impact on keratinocyte proliferation, migration, or inflammatory response, it modestly supported the survival of aged keratinocytes and it significantly modulated their differentiation in a manner that varied with both the age of the small EVs donor and the recipient keratinocytes. Notably, aging modified the microRNA cargo of fibroblast-derived EVs, which in turn influences keratinocyte behavior. These findings highlight that dermal EV-mediated signaling is modulated by the aging status of both sender and target cells, providing novel insights into the molecular mechanisms underlying dermis-to-epidermis communication during aging.

Growing evidence suggests that age-related declines in balance and gait are major contributors to falls, loss of independence, and reduced quality of life in older adults, yet the underlying neural mechanisms remain incompletely understood. The aim of this scoping review was to provide an overview of electroencephalogram (EEG) power spectrum correlates of balance and gait control when standing or walking quietly, and while responding to sensory, mechanical, or cognitive disturbances, in older adults. This knowledge would be important for developing targeted interventions and rehabilitation strategies aimed at enhancing neural function, improving balance and gait, and ultimately reducing the risk of falls and disability among older adults. We further investigated within the identified studies the types of methods used for EEG signal acquisition, preprocessing, and motion artifact removal.

Experimental models such as heterochronic parabiosis and heterochronic plasma transfer have profoundly advanced our understanding of systemic aging, demonstrating that circulating factors can influence brain, vascular, and immune aging through cell nonautonomous mechanisms. These preclinical models have revealed that both pro-geronic and anti-geronic signals in blood can modulate neuroinflammation, neurovascular health, and cognitive resilience. However, despite their experimental promise, the clinical translation of these findings, particularly through plasma-based interventions in humans, remains fraught with uncertainty. This review critically examines the strengths and limitations of parabiosis-based paradigms as platforms for discovery, contrasts them with early human plasma infusion studies, and evaluates the current biological, medical, and ethical challenges associated with young plasma therapies. Therapeutic plasma exchange has also emerged as a potential rejuvenation strategy, but its mechanisms, efficacy, and longterm safety remain incompletely understood. We argue that future progress in systemic rejuvenation will depend on precise, mechanistically informed interventions-rather than broad, premature applications of plasma therapies, which require further validation through rigorous scientific investigation.

Considering that the body accumulates senescent fibroblasts during the progression of aging, the character of collagen fibrils secreted from the senescent cells associates with the skin condition. In this study, we examined the alteration of collagen fibrogenesis using groups of normal human dermal fibroblasts with different cumulative population doubling levels (PDLs). We found that the density of extracellular collagen fibrils in late PDLs was lower than that in early or middle PDLs, and their orientation was disturbed in late PDLs. Visualized type I procollagen imaging indicated that cells in late PDLs had a defect in the C-terminal propeptide (C-pp) cleavage of procollagen. Biochemical analyses confirmed decreases in intracellular C-pp and extracellular collagen accompanied by PDL progression. Cells in late PDLs downregulated BMP-1 and PCPE-1, and BMP-1 knockdown in cells of early PDLs decreased the amount of extracellular collagen and disturbed the fibril orientation. These fibrils contained more C-pp than the control fibrils. Our results showed that cell senescence decreases C-pp cleavage and secretion of type I collagen through downregulation of BMP-1, resulting in the accumulation of extracellular procollagen and loss of fibril orientation.

Allosteric regulation enables proteins to couple local structural changes to distal functional outcomes, yet the underlying mechanisms often remain difficult to fully decipher. Using yeast SIR2, an NAD ⁺ -dependent deacetylase, as a model system, this study systematically elucidates how cofactor binding reshapes its conformational dynamics and internal communication network. Through multiple 3-μs molecular dynamics simulations combined with a graph-based deep learning model (Neural Relational Inference), we identify a highly reproducible characteristic response across independent replicates: the β1-α2 loop near the active site undergoes pronounced rigidification, whereas several distal structural modules exhibit concomitant increases in flexibility, together forming a "core-locking with peripheral-release" dynamic mode. Further signal-pathway analysis reveals that the local and distal conformational changes are not independent; instead, they are interconnected through newly identified "relay-type" residues such as Pro214 and Thr224. These residues act as bridges, converting the previously β1-α2-centered centralized network into a relay-style network coordinated by multiple nodes, thereby establishing a continuous and directionally coherent allosteric cascade. Beyond mechanistic insights, we also identify a distal cavity spatially overlapping with key relay residues, whose physicochemical properties meet the criteria of druggable pockets. This structural convergence suggests that future small-molecule allosteric activators may exploit this intrinsic communication pathway to mimic or amplify the regulatory effects of the cofactor NAD ⁺. Given that NAD⁺ levels decline with aging, this cavity provides a rational target for designing longevity-promoting allosteric activators.

Identifying physiological sweet spots (optimal ranges for homeostasis) is essential for precision medicine. However, traditional statistical methods often rely on globally linear or locally jagged models that struggle to capture the smooth, non-linear nature of biological regulation in high-dimensional data. We present the Quantile Feature Selection Network (Q-FSNet), a neural network-based framework that integrates quantile regression, feature selection, and uncertainty estimation to identify biomarkers with sweet spots. Unlike traditional methods, Q-FSNet learns continuous response curves without requiring pre-specified number of change points. We further introduce Quantile Dirichlet Network (Q-DirichNet), a fully Bayesian extension that utilizes Dirichlet priors to automate feature shrinkage. Using data from the Canadian Longitudinal Study on Aging, we identified 25 metabolites with distinct homeostatic ranges for which biological age acceleration is minimized. The metabolites with sweet spots for biological aging include some derived from diet or produced by the gut microbiome; this highlights their potential for knowledge translation and public health impact. Our results, corroborated by existing literature, demonstrate that these sparse neural network-based methods offer a scalable and interpretable tool for discovering metabolic signatures of healthy aging vs. dysregulation in large-scale omics research.

Age-associated declines in skeletal muscle function are linked to cellular senescence and mitochondrial alterations, yet mitochondrial phenotypes in aged human myoblasts remain insufficiently characterized. Here, we examined primary skeletal muscle myoblasts from young and elderly donors to assess mitochondrial function, morphology, and mitochondria-endoplasmic reticulum (ER) contact sites (MERCS). Myoblasts from older donors exhibited senescence features, including elevated SA-β-gal activity and reduced Lamin B1 expression, accompanied by increased mitochondrial oxidative stress. Despite marked mitochondrial hyperfusion and increased mitochondrial DNA content, mitochondrial oxygen consumption rate and membrane potential per mitochondrial area were comparable between young and old cells. MERCS were significantly elevated in aged myoblasts and were reduced by scavenging mitochondrial reactive oxygen species (mtROS), indicating an association between oxidative stress and MERCS formation. These findings suggest that mitochondrial hyperfusion and enhanced MERCS accompany cellular aging in human myoblasts and may contribute to maintaining mitochondrial function under elevated oxidative stress.

Suspended animation, a state of extreme quiescence with microscopically invisible movement and development, is a remarkable yet poorly understood stress resilience strategy in animals. Here, we describe a newly discovered form of suspended animation inducible by high-population density in isosmotic liquids in C. elegans throughout larval development and adulthood. Transcriptomic, metabolomic and live-cell activity reporter imaging analyses reveal striking molecular and cellular landscape changes by such liquid-induced suspended animation (LISA), including remodeling of gene expression programs, energy metabolites, lysosomal and mitochondrial morphology. Genetic screens identify mutants with altered stress responses and survival against LISA. While key endo-lysosomal regulators promote survival during LISA, organelle remodeling and a neuronal axis via downstream neuropeptide and cAMP/PKA signaling orchestrate behavioral awakening from LISA. Our findings define a facile paradigm for reversible SA, providing a powerful model system to uncover key molecular and cellular mechanisms governing an extreme case of reversible life arrest and dormancy.

Mitochondria integrate senescence and apoptotic fates, yet it is unclear whether their ability to oxidize different fuels for energy production influences their vulnerability to senolytics in therapy-induced senescence (TIS). Using MitoPlates™ technology, we functionally mapped the mitophenotypes of TIS cancer cells by quantifying electron transport chain (ETC) flux from various NADH/FADH

Annual killifish of the genus Nothobranchius are naturally short-lived vertebrates that exhibit a wide range of aging characteristics typically observed in mammals. Here, we provide the first comprehensive whole-genome methylation map for two species, revealing local age-related as well as tissue-specific dynamics in the DNA methylome. Our maps and results support the annual killifish as a model organism and further highlight its value for studying aging including possible health status predictions in vertebrates.

Visceral adipose tissue (VAT) is increasingly recognized as a metabolically active organ that contributes to systemic metabolic dysfunction and aging. Accumulation of VAT is thought not merely to be a biomarker of but also a causal contributor to impaired metabolic health and reduced lifespan. In this Review, we summarize evidence from both animal and human studies to evaluate whether this causal relationship truly holds. Our assessment indicates that VAT is not inherently harmful; rather, its pathogenicity is context dependent and emerges under specific conditions, including lipid spillover combined with impaired preadipocyte differentiation, chronic inflammation, genetic susceptibility, hormonal changes and aging. We further explore how VAT-derived cytokines, exosomes, adipokines and lipotoxic metabolites mechanistically mediate its harmful effects. Lastly, we outline both established and emerging strategies aimed at reducing VAT burden or neutralizing its pathological impact. These insights highlight the view of VAT as a modifiable and context-sensitive contributor to metabolic disease and aging, and a promising target for promoting metabolic health and longevity.

Zinc is essential for life, and its regulation is tightly controlled by numerous transporters. As we age, our micronutrient levels, intake, and absorption change. Additionally, senescent cells increase with age and can contribute to the progression of age-related diseases. The study of Zn homeostasis in senescent intestinal cells is a relatively unexplored area that we aimed to investigate. Using two models to induce senescence in intestinal epithelial cells, etoposide treatment and gamma-irradiation, we observed that Zn levels increased in the cells, likely due to the upregulation of Zn transporters ZIP4 and ZnT7. This upregulated Zn seems to accumulate in the Golgi apparatus, and when Zn accumulation is blocked through chelation, a rescue effect occurs, marked by a decrease in senescence markers. This research emphasizes the role of Zn in senescent cells and its possible involvement in the development of senescence and the disrupted Zn homeostasis seen with aging.

Exposure to fine particulate matter smaller than 2.5 μm in diameter (PM2.5) has emerged as a critical environmental factor contributing to skin injury. As the skin is the body's primary barrier against the external environment, it is directly susceptible to PM2.5, which induces oxidative stress, inflammation, premature aging, and disruption of skin barrier function. Increasing evidence demonstrates that PM2.5 damages both epidermal keratinocytes and dermal fibroblasts, leading to cellular dysfunction through alterations in major signaling pathways, including the aryl hydrocarbon receptor (AhR), nuclear factor kappa B (NF-κB), activator protein 1 (AP-1), mitogen-activated protein kinase (MAPK), and nuclear factor erythroid 2-related factor 2 (Nrf2). These molecular perturbations accelerate skin aging and impair protective functions, highlighting the need for effective intervention strategies. Botanicals and their bioactive phytochemicals have attracted growing interest for their antioxidant and anti-inflammatory properties, which may counteract PM2.5-induced damage. By targeting redox imbalance and inflammatory signaling, natural compounds represent a promising approach for protecting skin health. This review highlights the role of PM2.5 in skin injury and critically examines botanical strategies that may mitigate PM2.5-induced skin damage and premature aging.

Sarcopenia, characterized by age-related decline in muscle mass and function, is associated with falls, disability, frailty, and mortality in older adults. However, sarcopenia frequently remains unrecognized in the emergency department (ED). We aimed to determine the prevalence, risk factors, and short-term outcomes of sarcopenia among older adults presenting to the ED.

Dietary restriction may extend lifespan by improving late-life gut health. Because micronutrients mediate the effects of macronutrient ratios on longevity, we examined how cholesterol limitation affects gut health in female Drosophila melanogaster. Low-cholesterol diets increased intestinal permeability and reduced lifespan, however, not all flies lost barrier function before dying. This indicates gut dysfunction is either a marker of ageing, or contributes to death, but predominantly during dietary cholesterol limitation.

Ageing is traditionally conceived as a continuous process of progressive physiological decline. Recent evidence across multiple species challenges this view, suggesting ageing may proceed through distinct phases. Here we present a rigorous statistical framework to test and refine the two-phase ageing model using longitudinal survival data from Drosophila melanogaster. We analyzed 1,159 individually tracked female flies from the Smurf assay, which identifies a transition from a non-Smurf state to a Smurf state characterized by increased intestinal permeability that precedes death. Using non-parametric hazard rate estimation followed by mechanistic modelling, we reveal three key findings. First, the Smurf transition rate follows a Gompertz-Makeham law, increasing exponentially with age. Second, contrary to previous constant-rate assumptions, newly transitioned Smurf flies exhibit remarkably high mortality - approximately 40% die within 24 hours - followed by an exponential decline in death rate. Third, we identified a subtle but statistically significant negative dependence between time spent non-Smurf and subsequent Smurf lifespan, though this relationship varies: flies transitioning before 200 hours show minimal dependence and higher early mortality. Our best-fit model captures the bimodal nature of mortality curves using simple, biologically interpretable functions. Validation using data from two mouse strains confirms the broader applicability of this framework. These results establish a quantitative foundation for the two-phase ageing paradigm and highlight a critical period of vulnerability immediately following the physiological transition to frailty.

Background: MicroRNAs (miRs) and transfer RNA fragments (tRFs) regulate diverse brain processes, from neurogenesis to neurological disease. While both these small RNA classes have been implicated in cell-type-specific regulation, most studies leaned on bulk measurements, due to technical limitations in detecting small RNAs using single-cell RNA sequencing. Consequently, the cell-type specificity of brain miRs and tRFs remains poorly characterized, limiting functional interpretation. Results: To generate a comprehensive, cell-type-resolved atlas of miRs and tRFs from live human brain tissues, we isolated neurons, astrocytes, microglia, and oligodendrocytes from neurosurgery-derived fresh human brain samples and profiled their small RNAs by RNA-sequencing. This revealed pronounced cell-type-specific differences in miR and tRF levels, identified novel small RNA cell-type markers, and provided insight into the genetic regulation of miR cell-type specificity. Notably, neurons exhibited elevated levels of 5'-tRNA halves compared to glial cells, including enriched fragments derived from glycine, leucine and lysine tRNAs. Finally, our resource enabled assignment of cell-type origins to miRs associated with healthy brain aging and tRFs linked to Alzheimer's disease. Conclusions: Highlighting the importance of cellular context for data interpretation, both human brain miRs and tRFs exhibit pronounced cell-type-specific differences associated with brain aging and neurodegenerative diseases. Combined with an accompanying statistical tool for miR cell-type enrichment analysis, this work provides a publicly available resource for resolving the cell-type origins of small RNAs in the human brain.

Abstract Background Neurodegenerative diseases, including Alzheimer's disease (AD), exhibit substantial clinical and molecular heterogeneity, complicating accurate diagnosis and development of effective therapies. Although multi-omics profiling provides unprecedented molecular resolution, systematic integration of high-dimensional, imbalanced data modalities with disease-relevant biological networks remains a methodological challenge. Methods We developed a network-informed multi-omics integration framework that combines data-driven molecular networks with brain transcriptomic, proteomic, and metabolomic data from 356 participants in the Religious Orders Study and Rush Memory and Aging Project (ROS/MAP). Utilizing 25 functional, data-driven multi-omics groups (DAD-MUGs) derived by graph embedding from the AD Atlas, co-expression-guided feature extraction and systematic two-phase feature balancing were applied to derive representative molecular features, which were subsequently learned using DAD-MUG-specific autoencoders to generate compact multi-omics expression scores. These were then used to identify molecular subgroups via hierarchical clustering. Subgroup robustness was assessed in an independent ROS/MAP cohort (n=327) using a two-round nested classification strategy. Results Subgroup identification based on DAD-MUG-derived expression scores resulted in five molecular subgroups exhibiting significant differences in cognitive performance and core neuropathological measures. Cross-validated nested classification using transcriptomic and proteomic data demonstrated reliable discrimination of subgroups. Applying these classifiers to the replication cohort, subgroup-trait association patterns showed strong agreement with discovery findings (Spearman {rho} = 0.65). Differential expression analysis further revealed stage-dependent biological patterns of brain pathologies, ranging from early synaptic and immune activation to mitochondrial bioenergetic dysfunction at disease transition and proteostatic impairment in advanced stages. Conclusion Using a balanced, network-informed multi-omics integration framework, we identified five molecular subgroups of brain aging, including a reference control subgroup and a distinct mixed subgroup characterized by amyloid, vascular pathology, and early-life adversity. Three additional subgroups formed a structured spectrum comprising molecularly Alzheimer's-like but cognitively and neuropathologically unimpaired At-risk controls, an intermediate stage, and typical Alzheimer's disease, with tau pathology differentiating advanced disease, underscoring the value of molecular subgroup identification beyond clinical diagnosis.

Progenitor cells in aged tissues undergo changes in their microenvironment that may impact their functionality during regeneration. Despite recent advances in understanding the role of adult lung progenitors, the impact of aging on these cells remains unclear. To analyze aging modifications, we used aged wild-type mice of 18-24 months old, and Zmpste24-/- deficient mice, which exhibit an accelerated aging phenotype. A three-dimensional organoid culture system was employed to assess the lung regeneration capacity. Additionally, mouse epithelial cells and fibroblasts were isolated and characterized with senescence and autophagy markers. Our findings revealed that lung epithelial cells from aged mice and Zmpste24-/- mice hold their regeneration capacity, maintaining their phenotype and a healthy cellular state through an increase in autophagy, particularly when co-cultured with healthy fibroblasts. Conversely, cultured fibroblasts from Zmpste24-/- mice show nuclear defects and acquire a senescent phenotype, characterized by mTORC1 activation and reduced autophagy, which in turn impairs organoid formation. Moreover, these progenitor cells become increasingly susceptible to mechanical stress with aging due to reduced nuclear lamins and the Zmpste24 defect. This vulnerability is illustrated by FACS sorting, which can further compromise their regenerative potential. Our results indicate that, in aging, progenitor cells and their fibroblast niche integrate microenvironmental signals that shape cell-cell interactions essential for lung regeneration.

Space travel is becoming accessible, yet our understanding of how space environment and microgravity (uG) affect biology, physiology, and health remains incomplete. We investigated uG effects on neuromuscular development and aging in Caenorhabditis elegans. Nematodes in uG showed downregulation of genes related to synaptic signaling, dopamine response, locomotion, and cuticle development, with impaired synaptic vesicle dynamics, reduced motility, and shorter body lengths. Aged worms in uG showed decreased collagen gene expression, increased motor neuron defects, synaptic vesicle accumulation and decreased release, and mitochondrial morphology collapse in body wall muscles, indicating accelerated aging. MEC-4 mechanoreceptor was identified as a key mediator of uG-induced body length reduction and changes in extracellular matrix gene expression. uG conditions suppressed mechanoreceptor genes, suggesting multiple mechanosensory systems are affected. Physical stimulation through culture medium with small beads in space mitigated many uG-induced expression changes, including mechanoreceptors, neuromuscular defects, and aging-related phenotypes. These results highlight mechanical stimuli's role in maintaining neuromuscular integrity during spaceflight and suggest restoring tactile input could counter health risks from reduced stimulation in long-term space missions.

Healthy brain development requires a coordinated process of postnatal cellular maturation throughout the first two decades of life that transforms neuronal morphology, connectivity, physiology, and gene expression. The maturation and stable maintenance of neuron identity is driven, in part, by large-scale reconfiguration of the neuronal DNA methylome. Neurons have uniquely high levels of 5-hydroxy-methyl-cytosine (hmC) compared to other cell types, yet the relative contributions of 5hmC and 5-methyl-cytosine (mC) remain unknown because most experimental assays do not distinguish these marks. We measured mC and hmC using bisulfite- and oxidative-bisulfite sequencing in excitatory and inhibitory neurons, along with mRNA and histone modifications, from the prefrontal cortex of 103 human donors, ranging from 38 days to 77 years of age. Up to half of all CG dinucleotides convert from mC to hmC in a gradual process extending throughout the first decade of life, dramatically reshaping the neuronal methylome. Asymmetric enrichment of hmC on the sense strand of actively transcribed genes increases in a linear, clock-like fashion throughout the lifespan, indicating a mechanistic link between transcription and hmC. We found that sex differences in X-linked DNA methylation in the human brain are primarily driven by hmCG rather than mCG, suggesting an important role for hmC in X-chromosome inactivation (XCI) and escape gene expression. We found key changes in 5hmC at dynamic cis-regulatory elements marked by changing cell type-specific levels of active and repressive histone modifications. Collectively, our findings reveal the dynamic trajectory of hmC in human neurons across the lifespan and highlight the association of DNA hydroxymethylation with transcription, chromatin state, and sex-specific gene regulation.

Oxidative stress contributes to age-related musculoskeletal decline, partly through disruption of glutathione-dependent redox homeostasis. Although creatine and β-hydroxy-β-methylbutyrate (HMB) have been individually linked to antioxidant and cytoprotective effects, their combined influence on systemic redox balance in older adults remains insufficiently characterized.To examine the effects of creatine plus HMB supplementation on oxidative stress biomarkers and composite redox indices, and to explore whether redox adaptations co-vary with changes in functional measures in physically active older adults.In a randomized, double-blind, placebo-controlled crossover trial, 30 physically active older adults (62.7 ± 5.3 years; 20 men, 10 women) completed two 6-week intervention phases (3 g/day creatine + 3 g/day calcium HMB vs. placebo) during supervised exercise training. Primary endpoints were oxidized glutathione and the Glutathione Redox Index. Secondary biomarkers and composite indices were analyzed with false discovery rate (FDR) control. Percent changes (Δ%) in functional tests were examined exclusively as exploratory correlates of redox adaptations.Supplementation was associated with attenuation of the placebo-related increase in oxidized glutathione and nominal preservation of the Glutathione Redox Index, although these effects did not remain significant after FDR adjustment. In men, a nominal increase in malondialdehyde was observed under supplementation. Exploratory analyses indicated weak associations between changes in composite redox indices and Δ% functional measures.Creatine plus HMB supplementation was associated with nominal modulation of glutathione-centered redox balance during training in active older adults. Exploratory redox-function associations support further investigation in larger, adequately powered trials.

Osteosarcopenia, a composite disorder of age-related sarcopenia and osteoporosis, currently lacks targeted therapeutic interventions. We hypothesized that skeletal muscle-specific LDLR knockdown could reverse musculoskeletal functional decline via the Wnt/β-catenin signaling pathway.

Compulsory schooling laws introduced across Europe in the 20th century aimed to expand educational attainment and may have shaped key determinants of cognitive health. We exploit variations in compulsory schooling laws in England to assess whether increased education, mandated by these policies, impacts cognitive function, dementia risk, and related risk factors in older age. We focus on two major reforms: the 1947 reform, which raised the school-leaving age from 14 to 15, and the 1972 reform, which increased it to 16. Using data from the English Longitudinal Study of Ageing (ELSA) and a novel dementia risk algorithm based on the Harmonized Cognitive Assessment Protocol (HCAP), we find that while both reforms increased schooling, their effects on cognitive aging differ. We find suggestive evidence that the 1947 reform improved cognitive outcomes and reduced dementia and mild cognitive impairment risk specifically for women and individuals from low parental education backgrounds. In contrast, we find no statistically detectable reductions in dementia risk associated with exposure to the 1972 reform. Our findings suggest that the impact of compulsory schooling laws on cognitive aging and dementia is context dependent. Findings highlight the importance of institutional context and heterogeneity when assessing the long-run effects of education policies.

Aging involves a gradual decline in physiological functions and increased susceptibility to damage and disease. Suppressing reactive oxygen species (ROS) production and inflammatory responses is critical for delaying age-related cellular decline. Astragalus membranaceus is one of the important health functional foods worldwide due to its health benefits, including antioxidant and immunomodulatory properties. While the root is the most commonly utilized part, other plant parts remain largely unexplored despite their potential benefits. This study investigated that A. membranaceus sprouts and their unique constituents could regulate ROS production, inflammation-related senescence-associated secretory phenotype components, and extracellular matrix in fibroblasts. Sprouts showed better biological activities than roots; molecular networking analysis revealed 15 sprout-specific flavonoid-3-O-glycosides, including one new natural and eight previously unreported ones (1-9), as key metabolites underlying this result. Astraflavonol H (8) exhibited potent bioactivity. Molecular target analysis of the compound using ligand-based in silico tools revealed the involvement of the Kelch-like ECH-associated protein 1 (KEAP1)-nuclear factor erythroid 2-related factor 2 (NRF2) pathway. Western blotting analysis revealed KEAP1 downregulation and NRF2 and heme oxygenase-1 upregulation. Molecular docking indicated the Kelch domain of KEAP1 as the binding site. Astraflavonol H increased NRF2 protein stability and attenuated tumor necrosis factor-α-induced Janus-activated kinase and signal transducer and activator of transcription-1 phosphorylation. Overall, this study highlights the potential of A. membranaceus sprouts and their components as anti-aging foods.

The proteasome is essential for cellular protein homeostasis through selective destruction of damaged and misfolded proteins. Failure of proteasome-dependent turnover accompanied by accumulation and aggregation of aberrant proteins is a hallmark of aging and late-onset neurodegenerative diseases. SKN-1A/Nrf1, a member of the NFE2L/Nrf family of transcription factors, is a master regulator of proteasome biogenesis. Through transcriptional control of proteasome subunit gene expression, SKN-1A/Nrf1 controls homoeostatic and stress-responsive upregulation of proteasome levels in adaptation to proteasome dysfunction or protein misfolding. SKN-1A/Nrf1 acts in concert with another Nrf family transcription factor, SKN-1C/Nrf2, to regulate many aspects of physiology including stress responses, redox balance, immunity, and metabolism. Here, we demonstrate that a small deletion in the promoter of the pbs-5 gene, which encodes an essential proteasome subunit, uncouples its expression from transcriptional regulation by SKN-1A/Nrf1. This disruption leads to compensatory SKN-1A/Nrf1-dependent upregulation of other proteasome subunit genes, resulting in a homeostatic imbalance in proteasomal gene expression. This pbs-5 regulatory mutation phenocopies some, but not all, aspects of SKN-1A/Nrf1 inactivation, providing evidence that coordinated regulation of proteasomal subunit gene expression underlies a subset of SKN-1A/Nrf1's physiological roles. In comparing the effects of the pbs-5 promoter deletion with isoform-specific inactivation of SKN-1A or SKN-1C, we show that the pbs-5 promoter mutation completely abrogates multiple lifespan extension paradigms. These results reveal that coordinated homeostatic regulation of proteasome subunit gene expression is critical for longevity and healthy aging.

Previous epidemiological evidence has indicated that mushroom intake may reduce sarcopenia risk in older adults, though this is unconfirmed by laboratory studies. Here, we examined whether lentinan (LNT), a mushroom polysaccharide, influences C2C12 myoblast differentiation and attenuates age-related muscle atrophy in aged mice. In vitro, LNT significantly enhanced C2C12 differentiation, increasing myotube diameter and myogenic differentiation 1 (MyoD1)/myogenin expression. In vivo, LNT treatment enhanced grip strength and exercise endurance in naturally aging mice while also slowing muscle mass and cross-sectional area loss. Transmission electron microscopy analysis revealed that low and medium doses of LNT significantly increased mitochondrial abundance and improved mitochondrial morphology in both differentiated C2C12 and skeletal muscle tissues. Furthermore, the expression intensities of crucial proteins participating in mitochondrial biogenesis (PGC-1α, Nrf2, and TFAM) were significantly upregulated in cell samples. These results indicate that LNT may mitigate sarcopenia through activating the PGC-1α/Nrf2/TFAM and promoting mitochondrial biogenesis.

Negative social ties, or "hasslers," are pervasive yet understudied components of social networks that may accelerate biological aging and morbidity. Using ego-centric network data and DNA methylation-based biological aging clocks (i.e., DunedinPACE and age-accelerated GrimAge2) from saliva from a state representative probability sample in Indiana, we examine how negative social ties are associated with accelerated biological aging and a broad range of health outcomes, including inflammation and multimorbidity. Negative relationships are not rare within close relationships, as nearly 30% of individuals report having at least one hassler in their network. These hasslers tend to occupy peripheral network positions and are more likely to be connected through weak, uniplex ties. Importantly, exposure to negative social ties follows patterns of social and health vulnerability, with women, daily smokers, people in poorer health, and those with adverse childhood experiences more likely to report having hasslers in their networks. Having more hasslers is associated with accelerated biological aging in both rate and cumulative burden: Each additional hassler corresponds to approximately 1.5% faster pace of aging and roughly 9 mo older biological age. Moreover, not all hasslers exert the same influence; kin and nonkin hasslers show detrimental associations, whereas spouse hasslers do not. Finally, a greater number of hasslers is associated with multiple adverse health outcomes beyond epigenetic aging. These findings together highlight the critical role of negative social ties in biological aging as chronic stressors and the need for interventions that reduce harmful social exposures to promote healthier aging trajectories.

Bone marrow adipose tissue (BMAT) has been linked to negative bone health outcomes, and a high level of bone marrow adipocyte accumulation is observed during aging and in individuals with diabetes and obesity. This study explores the relationships between BMAT, age, metabolic health, and the impact of their interactions on bone turnover in a cross-sectional cohort of healthy women and men. Levels of bone turnover biomarkers, procollagen type 1 N-terminal propeptide (P1NP) and β-CrossLaps, were determined alongside dipeptidyl peptidase-4 (DPP4) concentration and activity as biomarkers of metabolic health. We used magnetic resonance imaging to assess proton density fat fraction to quantify BMAT mass in healthy individuals and correlated results to sex, age, body mass index (BMI), and glycated hemoglobin A1c (HbA1c), which represents long-term glycemic control. Age was the strongest determinant of increased BMAT mass, explaining more than a third of its overall variation, as well as a robust determinant of bone turnover. A sex-specific correlation pattern was observed between BMAT and bone turnover: women displayed a trend for a positive correlation of BMAT, which depended on age. In men, BMAT mass correlated significantly, but inversely, with both biomarkers, which was also age-dependent. DPP4 concentration and activity were positively associated with P1NP in both sexes, and these relationships were independent of age, BMI, or HbA1c. These findings indicate that the impact of BMAT on bone turnover may be age-dependent, whereas metabolic regulator DPP4 is linked to bone turnover independently of metabolic health or aging.

Sarcopenia and cognitive impairment are common age-related conditions that severely affect older adults' quality of life. Diet quality, a modifiable factor, has been associated with muscle health and cognitive function, suggesting a potential interaction between sarcopenia, diet, and cognition. However, this relationship remains underexplored.

Skeletal muscle metabolic and physical capacities are influenced by both genetics and load status and decline with age. Recent advances in sequencing have detailed cell types at unprecedented detail; yet these approaches do not scale to adequately model human muscle physiological heterogeneity. We produced a powerful resource for ageing studies, including consistent deep transcriptomic profiles of 1,675 human muscle biopsies (approx 28,000 genes per profile) and multiple single-cell spatial transcriptomic technologies. We present several novel models of tissue ageing. Five Quantitative network models (QNMs), built using >40 trillion calculations and 930 human muscle transcriptomes, modelled aging and the influence of load status. Additional differential expression (DE) signatures for atrophy, hypertrophy and cardio-respiratory adaptation were integrated with single-cell RNAseq and cell-specific bulk profiles to reveal cell-enriched modules and the topology of human skeletal aging. Rapamycin transcriptomes from cultured muscle and endothelial cells, along with in vivo signatures for insulin resistance and sex, were integrated into these analyses. We show that >3,000 genes are DE with muscle age (equally up and down); that a novel pre-frailty signature in elderly subjects has a remarkably strong overlap with the response of healthy muscle during experimental atrophy and that the hypertrophy signature in elderly muscle, but not young muscle, opposes the age-regulated transcriptome. We report that non-responders for hypertrophy or gains in cardio-respiratory capacity have highly distinct genome-level response to exercise. QNM revealed cell-specific processes in endothelial cells and fibroblasts, including novel interactions between insulin sensitivity, age and senescence. From two hundred and eighty-six hub genes consistent in both young and old muscle network models, 27% had known roles in muscle biology, while of the top 50 hub genes (45% protein coding), 80% were newly linked to human muscle biology, including ARHGAP4, CEP131 and IFITM10 and many short- and long- noncoding RNAs. Many genes demonstrated extreme changes in topology in old muscle, such as the neddylation and aging linked gene, DCUN1D5. GeoMX-based spatial muscle fibre-type profiling (57 regions), along with Xenium (8 regions) and Merscope (54 regions) single-cell spatial technologies located key aging, frailty and load-responsive genes to individual cell types and provided novel insight into the location of autocrine/paracrine secreted factors such as GDNF, while IL6 was located to rare endothelial cells. A machine-learning model ranked the factors most associated with the topological changes with age. This prioritised network features over DE signatures, highlighting positive correlating edges to down-regulated genes during atrophy, genes up-regulated by Rapamycin and both positive and negative correlating insulin sensitivity features, along with gene hub status, best explained muscle ageing. Genome level modelling produced an independently validated transcriptomic age clock and found it to be invariant to muscle load status in people >50y, while we revealed novel interactions between gene length and age. Release of an unprecedented level of consistently aligned genomic data, along with QNMs with >7,000 searchable modules, provides a powerful resource for the aging research communities

Altered biomolecular condensate dynamics are increasingly implicated in age-associated neurodegenerative disorders, yet the molecular principles governing these changes remain incompletely understood. Here, we demonstrate that aged cells across diverse cellular and organismal models harbor pre-formed, viscous, and persistent stress granules (SGs), which we term alt-SGs. These persistent condensates confer protection to senescent cells under fluctuating stress conditions. Comparative analyses reveal that alt-SGs exhibit elevated RNA-binding protein (RBP)-to-RNA ratios, underscoring a shift in condensate stoichiometry. By quantifying SG composition and dynamics in live cells and in vitro, we establish that RNA concentration is a key determinant of condensate material properties, molecular composition, and dissolution capacity. Importantly, aging cells display diminished absolute RNA concentrations due to reduced RNA metabolic activity. Reactivation of RNA metabolism restores RNA/RBP ratios within SGs and alleviates aging-associated phenotypes. Together, our findings highlight RNA metabolism as a central regulator of condensate stoichiometry and function, linking metabolic decline to altered phase behavior and cellular aging.

Type 1 diabetes (T1D) is an autoimmune disease where beta cells are destroyed by cytotoxic T cells. Calorie restriction (CR) enhances glucose homeostasis and promotes beta cell longevity and was used as therapeutic strategy for T1D prior to the discovery of insulin. However, a significant knowledge gap remains regarding its effects on beta cells during the pathogenesis of auto-immunity. We demonstrate that CR enhances glucose homeostasis, reduces beta cell load, and delays T1D onset in NOD mice. CR induced a largely post-mitotic beta cell state marked by selective loss of beta cell identity markers, reduced DNA damage and beta cell senescence, and increased PD-L1 within the islet microenvironment. This beta cell phenotype correlates with anti-inflammatory and exhausted immune cell states in the NOD islet. Together, these findings indicate that CR improves glucose homeostasis and remodels the islet microenvironment to pro-mote beta cell longevity via a pro-tolerogenic immune microenvironment that reduces the risk for autoimmune diabetes.

The naked mole-rat is a subterranean rodent adapted to extreme hypoxia and low metabolic demands, with an exceptionally long lifespan relative to its small body size, while maintaining reproductive capacity. Using 16S rRNA gene sequencing of 24 samples and whole-metagenome sequencing of 11 samples from individuals up to 15 years of age, we characterized the gut microbiota and showed its complexity and distinctiveness compared with that of other rodents, including mice, squirrels, and rabbits. Although all animals were born and raised in a laboratory setting, the gut microbiota remained taxonomically stable across ages and retained key taxa previously reported in wild naked mole-rats (e.g., Treponema and Desulfovibrio). Metagenome-assembled genomes revealed the presence of archaeal methanogens and termite-gut-associated bacteria (e.g., Methanobacteria within Euryarchaeota and Avelusimicrobium within Elusimicrobiota), together with genes involved in hydrogen metabolism and archaeal methanogenesis. Compared with mice, the naked mole-rat gut microbiota was enriched in carbohydrate-active enzymes targeting plant cell-wall polysaccharides, resembling those found in ruminants. We also detected evidence of flagellates, ciliates, and fungi, which may further contribute to polysaccharide degradation and fermentation, potentially within the enlarged cecum. Together, this comprehensive analysis provides distinctive gut microbial features of the naked mole-rat that may be associated with the naked mole-rat's low metabolic rate and exceptional longevity.

Cellular senescence features a durable cell-cycle arrest and a pro-inflammatory senescence-associated secretory phenotype (SASP) driven in part by chromatin remodeling. The histone variant H2A.Z plays an essential role in regulating gene expression through modulating nucleosome dynamics and is known to regulate the expression of cell cycle genes during the early stages of cellular senescence. However, how the intrinsic stability of H2A.Z-containing nucleosomes plays a role in the establishment of the senescent phenotype remains unexplored. To investigate this, we employed H2A.Z R80C, a H2A.Z mutant that destabilizes nucleosomes by disrupting histone-DNA interactions. We observed that expression of H2A.Z R80C causes suppression of SASP in senescent primary human fibroblasts, without affecting expression of cell cycle genes. H2A.Z knockdown did not suppress the SASP, demonstrating that SASP suppression is likely due to altered stability of H2A.Z-containing nucleosomes rather than loss of H2A.Z function. Mechanistically, SASP suppression is linked to decreased H3K27ac at SASP gene loci. These findings offer a novel avenue for understanding and manipulating the SASP during aging and other senescence-related pathologies.

Protein prenylation is a widespread post-translational modification (PTM) that regulates membrane association and signaling; dysregulation of this process leads to a variety of diseases. Metabolic labeling with probes containing bioorthogonal functionality has revolutionized the study of many protein modifications, including prenylation. However, that approach requires two steps, including metabolic incorporation and subsequent bioorthogonal reaction to install chemical reporters. Here, we present the development and application of tellurium-containing isoprenoid analogues that can be incorporated through a single enzymatic step and enable the direct quantification of prenylation at the single-cell level by mass cytometry. This robust methodology was examined in a variety of cell lines and used to show that prenylation levels are perturbed in autophagy-deficient L6 cells, a model for certain features of aging. Modification of tellurium-labeled proteins through the oxidation-controlled strain-promoted tellurophene-alkyne cycloaddition reaction also enabled the identification of prenylation targets by chemical proteomics. This methodology bridges proteomic and multiplexed single-cell analyses, opening up promising avenues for exploring a variety of post-translational modifications.

Peucedanum japonicum Thunb. (PJ), also known as costal hog fennel, is an edible medicinal plant recognized for its potential health benefits. We previously demonstrated the protective effects of PJ against muscle atrophy in young mice. In the present study, we investigated whether PJ also inhibits age-related muscle loss in aged mice. PJ treatment of primary myoblasts derived from aged mice attenuated myotube diameter reduction, suppressed the expression of atrogenes, and prevented the fast-to-slow myosin heavy chain (MHC) fiber type transition. Additionally, PJ improved mitochondrial respiratory capacity, accompanied by increased PGC1α expression and phosphorylation. Aged mice (20 months old) were fed diets supplemented with 0.1% or 0.2% PJ for eight weeks. PJ supplementation enhanced muscle strength and physicalrformance parameters, including treadmill endurance and stride length. Increases in lean body mass, muscle weight, cross-sectional area (CSA), and the ratio of MHCII to MHCI fibers were observed. These improvements were associated with reduced ubiquitin-dependent protein degradation and the downregulation of atrogenes. Furthermore, PJ supplementation promoted mitochondrial activity via PGC1α and stimulated mitochondrial biogenesis through the Nrf1-Tfam pathway. 4-Caffeoylquinic acid (4-CQA), a major bioactive compound in PJ, attenuated myotube atrophy and enhanced mitochondrial respiration in aged myoblasts. These findings suggested that PJ, along with its active compound 4-CQA, has therapeutic potential for combating age-related muscle loss.

Pregnancy and aging are associated with stress on the body and show multi-system physiological changes. We asked whether we can learn about aging from the changes in pregnancy. To do so, we analyzed weekly cross-sectional data on 70 lab tests from 300,000 pregnancies and 1.4 million non-pregnant females aged 20-89. Using a biological age model trained on non-pregnant females, we observed that pregnant females' apparent age dropped by 5 years in the first trimester, rose by 20 years toward delivery, and recovered postpartum. Pregnancy complications increased apparent age by 2-6 years. Certain systems exhibited apparent rejuvenation - opposite trends in pregnancy vs aging - including renal, iron, and most liver tests. Others, such as coagulation, thyroid, muscle, and metabolism, showed apparent aging. Notably, the aging-like mechanisms of pregnancy differed from normal aging, suggesting superficial similarity, whereas the rejuvenation-like mechanisms may offer clues for slowing aspects of biological aging.

As global human life expectancy continues to rise, accompanying increases in healthspan that prevent morbidity expansion become increasingly imperative. Population lifespan can increase in distinct ways, for instance through rectangularisation (steepening) or triangularisation (flattening) of survival curves. These two demographic changes, particularly rectangularisation, occur frequently across human and model organism populations, yet their biological determinants and effects on healthspan and morbidity are largely unknown. Notably, these modes of life-extension occur when parameters of the Gompertz mortality model (capturing exponential age-increases in mortality rate) change inversely, a widely-reported phenomenon known as the Strehler-Mildvan correlation, whose biological basis also remains unexplained. We therefore investigated longitudinal health, morbidity and lifespan in 30 Caenorhabditis elegans cohorts using multiple life-extension protocols. We report that survival curve rectangularisation results from healthspan expansion in short-lived population members, whereas triangularisation from healthspan and morbidity expansion in long-lived population members. Interestingly, rectangularisation and triangularisation respectively decrease and increase inter-individual variation in the ageing process, and the mode of life-extension that occurs depends on levels of existing variation. Notably, triangularisation was more effective at extending lifespan without morbidity expansion. Analysis of fruit fly and mouse data show that these biological determinants of the Strehler-Mildvan correlation are also largely evolutionarily conserved.

Extension of healthy longevity is an important health program in long-lived countries like Japan. The Dietary Reference Intakes for Japanese 2025 established tentative dietary goals for the prevention of lifestyle-related diseases; however, the adequate macronutrient energy ratios in a diet to support longevity remain unclear, particularly for the protein content. This study aimed to evaluate the associations between protein or amino acid intakes and healthy aging in the Japanese population.

This secondary data analysis aimed to determine the nature of the relationship between obstructive sleep apnea (OSA) risk, biological age acceleration, and nonspecific chronic low back pain (CLBP). 199 adults with CLBP aged 18 to 82 years participated in the study. Based on the STOPBANG questionnaire, 104 had a low OSA risk and 95 had an intermediate or high OSA risk. Dunedin Pace of Aging Computed from the Epigenome (DunedinPACE), Horvath's, Hannum's, PhenoAge, and GrimAge clocks were used to determine biological age and pace of biological aging. Individuals with low OSA risk reported increased DunedinPACE compared to those with intermediate/high OSA risk (p < 0.001). There was a significant correlation between the risk for OSA and biological age acceleration measured by PhenoAge as well as pace of biological aging (p < 0.05). Mediation analysis detected indirect effects of OSA risk on chronic pain outcomes through the pace of biological aging. Targeted interventions addressing OSA risk offers a promising therapeutic strategy. This could be particularly valuable for aging populations where both accelerated biological aging and chronic pain conditions are prevalent, offering a more holistic approach to improving nonspecific chronic pain outcomes through quality of sleep and restfulness.

Successful aging (SA) is a key focus in gerontological research, highlighting the importance of maintaining physical, cognitive, and social well-being. Nutrition is a critical determinant of health in older adults, and sustainable healthy eating behaviors are increasingly recognized for their role in promoting SA and longevity. However, evidence examining this relationship within the Saudi context remains limited.

Reactive oxygen species (ROS)-induced cell damage contributes to many diseases. However, ROS also contribute to cell signaling and immune defences. As ubiquitous thiol peroxidases, peroxiredoxins (Prdx) play integral roles in balancing ROS functions. High levels of Prdx6 are associated with increased metastasis and resistance to chemotherapy, rendering Prdx6 a therapeutic target for treatment of a broad range of cancers. However, Prdx6 has additional activities, in lipid signaling and selenocysteine metabolism, and it remains unclear how Prdx6's thiol peroxidase activity contributes to disease. Here we have investigated the role/s of Prdx6 in the nematode worm Caenorhabditis elegans. Consistent with a ROS-protective role for PRDX-6, prdx-6 mutant C. elegans exhibit elevated levels of lipid oxidation, more apoptotic corpses in their germline and are more susceptible to the toxicity of diethyl maleate. However, unexpectedly, prdx-6 mutant C. elegans are more resistant to other forms of oxidative stress, long-lived and resistant to infection with two opportunistic human pathogens; the gram-positive bacteria Staphylococcus aureus and the dimorphic yeast Candida albicans. Our data suggest these phenotypes are associated with increased activity of the NHR-49(PPARα/HNF4) transcriptional regulator and intestinal expression of the Flavin monooxygenase, FMO-2. FMO-2 has a conserved, pro-survival function and is up-regulated in response to various stresses, including peroxides and S. aureus infection. Here we reveal that fmo-2 expression is also increased as an NHR-49-dependent protective response to C. albicans. Consistent with increased NHR-49 activity, prdx-6 mutant animals also contain increased levels of mono-unsaturated fatty acids. Accordingly, we propose that elevated expression of fmo-2 and other NHR-49 up-regulated genes contribute to the increased arsenite resistance and innate immunity of prdx-6 mutant animals. These findings further illustrate the complex roles that ROS, PRDX and lipid oxidation can play in oxidative stress resistance, immunity and ageing.

The molecular and cellular basis of aging and its associated functional decline remains poorly understood. Even free-living microorganisms age and, in yeast, replicative aging shares key hallmarks with human cellular senescence, including progressive cell enlargement. Recent work has shown that chemical and genetic manipulations that increase cell size promote the onset of senescence in both yeast and human cells, suggesting that cell enlargement can drive some of the physiological changes associated with aging. Here, we quantitatively determined how cell enlargement contributes to age-associated physiology in yeast by combining automated aging technologies with quantitative proteomics. We find that the majority of aging-associated proteome remodeling can be recapitulated by genetically enlarging young proliferating cells. These enlarged cells exhibit accelerated proteome aging and shortened replicative lifespans, while smaller cells are longer-lived. While cell enlargement is the predominant factor driving proteome remodeling during aging, we also identified a minority of aging-specific molecular markers whose expression influences lifespan. Together, our results demonstrate that cell enlargement is a major driver of aging-associated proteome remodeling and influences lifespan independently of established aging factors such as extrachromosomal rDNA circles.

Cortical myelination is critical for circuit function, plasticity, and long-term stability in the adult brain. With age and disease, the capacity to restore myelin after oligodendrocyte (OL) loss declines, and this failure is thought to reflect intrinsic limitations of OL precursor cells (OPCs) and a loss of permissive cues within the cortical environment. Here, using single-OL ablations and intravital imaging in mice, we show that as cortical remyelination efficiency declines, OPC motility declines, a phenomenon that can be mimicked by blocking CXCL12/CXCR4 signaling. Counter to prevailing notions, however, we find that even in aging, OPCs retain the capacity to generate new OLs and sheath axons, which can be rekindled by a graded demyelinating stimulus, inducing a more juvenile OPC motile state. This reveals an unrecognized remyelination potential in aging and identifies OPC dynamics as a key determinant of cortical remyelination, a property that could be targeted to improve myelin repair.

Aging is a complex process characterized by the accumulation of molecular damage that leads to cellular dysfunction and tissue deterioration. Among the various types of contributing molecular damage, aberrant protein crosslinks are recognized as a key contributor to age-related pathologies. Crosslinks occurring at lysine and arginine residues, such as advanced glycation end-products (AGEs) and carbamylation, have attracted considerable attention of the aging research community. In contrast, the roles of cysteine-derived crosslinks in aging pathobiology remain underappreciated. While native disulfide formation is essential for protein structure and function, the same redox features that make cysteine indispensable to protein biochemistry also render it particularly susceptible to nonspecific disulfide crosslinking. The body exploits specialized protective thiols such as glutathione to maintain redox homeostasis and counteract the deleterious effects of aberrant disulfide formation. However, these endogenous protective measures decline with aging, resulting in the accumulation of oxidative cysteine modifications. In this review, we highlight the emergent roles of cysteine-related molecular damage in age-related disease. Drawing inspiration from endogenous protective thiols, we survey progress in the development of small-molecule therapeutic thiols that show promise in mitigating damage caused by the accumulation of cysteine-derived crosslinks. Understanding the relationship between these aberrant crosslinks and protective thiol interventions in aging diseases, as well as how therapeutic thiols can be improved, is critical for the development of comprehensive treatments.

Ocular fundus neovascularization (OFN) is a leading cause of irreversible vision loss. Conventional antivascular endothelial growth factor (anti-VEGF) therapies indiscriminately suppress pathological and reparative angiogenesis and fail to correct the senescence- and inflammation-driven microenvironment that sustains disease progression. Senescent endothelial cells (ECs) form the structural scaffold of pathological vessels, while neighboring senescent microglia exacerbate inflammatory signaling, together deteriorating the reactive oxygen species (ROS)-rich vascular-immune microenvironment. Here, we develop an injectable ROS-responsive senolytic hydrogel (PCC1/PHCF-Gel) that enables lesion-activated, sustained intraocular release of procyanidin C1 (PCC1), overcoming rapid clearance, oxidative degradation, and poor lesion retention associated with free PCC1. In oxygen-induced retinopathy and choroidal neovascularization models, PCC1/PHCF-Gel markedly reduces retinal senescence, suppresses pathological neovascularization, and restores neuroretinal function, outperforming symptom-directed therapies anti-VEGF therapy. Single-cell RNA sequencing reveals selective elimination of two pathogenic senescent cell subpopulations-CXCR4

The gut microbiota plays a key role in aging and longevity. Therefore, identifying longevity-associated microbes in healthy and long-lived individuals and elucidating the molecular mechanisms through which they influence longevity are essential steps toward developing effective anti-aging interventions. In this study, we performed 16S rRNA sequencing on 301 fecal samples collected across three age groups. Long-lived individuals (≥ 90 years) had more diverse gut microbiota than typical older individuals (60-89 years), with diversity comparable to that of younger adults (45-59 years). Compared with typical older individuals, long-lived individuals exhibited a marked increase in the relative abundance of Bacteroidota and Akkermansia, accompanied by a decreased abundance of Prevotella_9 and Megamonas. Additionally, the microbiota from this age group showed significant enrichment in unsaturated fatty acid metabolism, ketone body synthesis and degradation, and tryptophan metabolism, suggesting that differences in microbiota composition and function may contribute to longevity. Finally, we developed a qPCR-based method to detect differentially abundant microbiota and established a classification model capable of distinguishing between age groups. In conclusion, the unique composition and function of the gut microbiota in long-lived individuals offer insights for identifying methods and targets for anti-aging interventions. KEY POINTS: • Long-lived individuals exhibited a marked increase in Bacteroidota and Akkermansia • Long-lived individuals exhibited enrichment in unsaturated fatty acid metabolism • We developed a qPCR-based method to detect differentially abundant microbiota.

Metabolic dysfunction-associated steatohepatitis (MASH) is characterized by steatosis, inflammation, hepatocellular injury and fibrosis, with the capacity to progress to cirrhosis and hepatocellular carcinoma. Recent evidence highlights cellular senescence, particularly in hepatic stellate cells (HSCs) as a key regulator of MASH pathogenesis. Senescent HSCs exhibit a context-dependent duality whereby, while transient senescence limits fibrosis through cell-cycle arrest, matrix degradation and enhanced immune clearance, persistent senescence under chronic metabolic and inflammatory stress drives disease progression. Through an expanded senescence-associated secretory phenotype (SASP), senescent HSCs exacerbate inflammation, promote extracellular matrix deposition, alter immune responses and facilitate malignant transformation. The present review summarizes the molecular mechanisms inducing HSC senescence, including lipotoxicity, oxidative stress, DNA damage, mitochondrial dysfunction and impaired autophagy. The mechanisms by which SASP factors mediate crosstalk between senescent HSCs and other cell types are discussed, including hepatocytes, macrophages, T cells and natural killer cells, collectively altering the inflammatory and fibrotic microenvironment of MASH. Finally, emerging therapeutic strategies targeting cellular senescence are highlighted, such as senolytics, senomorphics and biomarker-guided interventions, which may offer promising avenues for modifying the course of MASH and preventing disease progression.

The hippocampus, a key neural structure supporting episodic memory, comprises distinct subfields including the dentate gyrus (DG), Cornu Ammonis (CA1-3), and subiculum. Hippocampal subfields typically show age-related volumetric decline across adulthood, but the regional aging may be differentially vulnerable to cardiovascular risk factors. Here, we examined the association between hippocampal subfield volumes and cardiovascular risk indices-hypertension, blood pressure variation (BPV), body mass index (BMI), and waist-to-hip ratio-in groups of younger (n = 37, ages 18-29 years) and older adults (n = 22, ages 60-79 years). The findings revealed a specific link between cardiovascular health and hippocampal subfield volumes, with the subiculum showing greater sensitivity. Among younger adults, hypertension predicted smaller subiculum, while higher BMI correlated with larger CA1-2 volumes. For older adults, higher BPV predicted smaller subiculum volume, independent of hypertension that correlated with larger regional volume. Age moderated the relation between all indices and subiculum volume except waist-to-hip ratio. These findings highlight age-dependent, subfield-specific risk factors for hippocampal aging and underscore the potential for identifying sensitive periods for both risk and protection against late-life cognitive decline.

Chronic kidney disease (CKD) is becoming a global health concern due to its rising prevalence owing to the complex interplay of environmental, genetic, and epigenetic factors. Leukocyte telomere length (LTL) is a potential indicator of biological age in age-related diseases. Our objective is to investigate the association between LTL and CKD in Pakistani population to systematically synthesize existing evidence by investigating previously reported studies.

Aging is a heterogeneous phenomenon provoked by biological processes that still need to be fully understood. Frailty is a relevant outcome of aging reflecting biological decline that can be quantified through indices measuring the accumulation of functional deficits. Age-related declines may occur across multiple domains of functioning, and longitudinal study designs may better characterize decline within aging individuals. Thus, it is imperative to characterize how frailty indices that capture different functional domains associate with one-another over the natural lifespan, and across study designs. Here, the Clinical Frailty Index (CFI) and the Mouse Social Frailty Index (mSFI) were applied to male and female mice both longitudinally and cross-sectionally over the lifespan. An overall similar association with aging was apparent: within each cohort, both CFI and mSFI were strongly positively associated with age. The utility of the CFI and mSFI as age predictors within the longitudinal study was confirmed. Critically, a model developed within the longitudinal study based on CFI scores, mSFI scores, and sex was able to predict age better than alternative models using only one of the indices. This result suggests that the CFI and the mSFI capture intrinsically different elements of deficit accumulation with age. The same model also showed a good performance in predicting the age of mice in the cross-sectional study. Overall, these results demonstrate that the information captured by both frailty indices is relevant to aging, relationships between indices vary across study design, and both frailty domains are needed to produce better age predictions.

This study examines the extent to which the quality of one's relationships with spouse, children, friends, and other family members are associated with cognitive function in older adults by gender and racial identities, along with the mediation effect of depressive symptoms for these associations.

Response inhibition is more sensitive to aging than other forms of inhibitory control. Mounting evidence suggests that moderate-to-vigorous physical activity (MVPA) can promote response inhibition and age-related brain structure and function in the frontal cortex. Nevertheless, a limitation of existing work is that it primarily focuses on the direct influence of MVPA on response inhibition, without directly examining how MVPA affects the component task processes that are involved in response inhibition. ActiGraph GT3X+ accelerometers were employed to quantify MVPA and to categorize older adults aged 60-79 years old into a higher physical activity group (HG) and a lower physical activity group (LG). The participants in the two groups completed three novel versions of the stop-signal task (SST), and structural as well as resting-state functional magnetic resonance images were collected. First, the behavioural data showed that the participants in the HG exhibited superior performance in inhibitory and attentional control than those in the LG. Second, the voxel-based morphometry (VBM) analysis revealed that the grey matter volume (GMV) in the right inferior frontal gyrus (rIFG) and the left superior frontal gyrus (lSFG) differed between the two groups. Third, the resting-state functional connectivity (rsFC) analysis with the rIFG, lSFG or right pre-supplementary motor area (rpre-SMA) as a seed region revealed that the participants in the HG had a greater functional connectivity (rsFC) than the LG. Finally, partial correlation analysis indicated that the GMV and the rsFC could jointly account for group differences in response inhibition and attentional control induced by MVPA. (1) MVPA is positively associated with response inhibition in older adults, and the positive relationship is associated with effective attentional resource allocation for faster attentional capture; and (2) distinct frontal subregions of the brain induced by MVPA participate in different cognitive processes involved in response inhibition; particularly, the benefit from rIFG enhancement may be realized through optimizing attentional capture.