Longevity Papers

Fatty acids are involved in disease risk and aging processes. In the US National Health and Nutrition Examination Survey (1999-2002), we tested for associations of total, saturated (SFA), monounsaturated (MUFA), polyunsaturated (PUFA), and subtypes of dietary fatty acids with DNA methylation-based aging biomarkers, adjusting for age, BMI, total energy intake, and sociodemographic and behavioral factors (N = 2260). Higher SFA and MUFA were associated with greater GrimAge2, an aging biomarker of mortality; PUFA was associated with lower Horvath1, Hannum, and PhenoAge (p < 0.05). Omega-3 and the PUFA:SFA ratio were negatively associated with Horvath1, Hannum, Vidal-Bralo, and PhenoAge. Notably, a one-unit increase in PUFA:SFA was associated with 1.05 years lower PhenoAge (95% CI = -1.87, -0.22). We found consistent positive associations for SFA subtypes and negative associations for PUFA subtypes with epigenetic aging; associations of MUFA subtypes varied. Future studies, including randomized controlled trials, are needed to investigate causality and downstream clinical outcomes.

Extracellular vesicles (EVs) contribute to the maintenance of organism-wide proteostasis by mediating intercellular communication. Loss of proteostasis and altered intercellular communication are associated with aging and age-related diseases, suggesting key roles for EVs. However, it is unclear how the proteome of the EVs changes with age. To identify EV-associated proteins (EVAPs) and their fate with age, we curated publicly available EV proteome data from C. elegans model organism and human. Our analysis reveals that EVs carry proteins with diverse functions, including those involved in protein quality control. We found that abundance of the EVAPs changes significantly with age, heat stress, pathogen infections and diseases. Many of these EVAPs also aggregate with age and overlap with Aβ-driven protein aggregates. Further, we identified human orthologs of C. elegans EVAPs from human brain tissues affected with Alzheimer's disease and breast cancer. This meta-analysis highlights EVs proteome composition, their abundance changes, and aggregation during aging, stress, infection and disease conditions. Overall, this study provides new insights into the dynamics of EV proteins during aging and may possibly help in identifying potential biomarkers for age-related diseases.

Understanding metabolic changes across the human lifespan is essential for addressing age-related health challenges. However, comprehensive metabolomic and lipidomic analyses, particularly in human plasma, remain underexplored. Herein, we performed untargeted metabolomics and lipidomics profiling of plasma collected from 136 individuals aged 0-84 years. This analysis reveals distinct metabolic signatures across life stages, with newborns displaying unique sphingosine (SPH) profiles, while aging was found to be characterized by elevated amino acid levels and lipid imbalances. Notably, we identified linear and nonlinear metabolic trajectories across the lifespan, highlighting critical transition points reflecting the key stages of metabolic reprogramming. By integrating these metabolic patterns, we developed an "aging clock" based on plasma metabolite profiling, thus providing a powerful tool to predict biological age. These findings offer new insights into the dynamic metabolic landscape of aging, paving the way for targeted interventions to improve healthspan and prevent age-related diseases.

Identification of targets of intervention to promote lifespan is crucial given lifespan is an important measure of public health. Telomere length and epigenetic clocks are key biological markers of aging, whether they are targets of intervention in men or women is unclear. We examined their associations with sex-specific lifespan in a Mendelian randomization study.

Aging is a complex biological process marked by a gradual decline in physiological function that contributes to increased vulnerability to disease and mortality. Numerous studies have investigated the cellular and molecular aspects of aging at single-cell resolution, yet the heterogeneity of cellular aging in an individual remains poorly understood. To enhance our ability to study aging at the single cell level, we developed a statistical framework to predict the age of individual cells based on their transcriptomic profiles. Our Bayesian approach estimates the most likely age of a cell given its read counts. We applied the model to data from Tabula Muris Senis and examined organ- and cell-type-specific transcriptomic signatures of aging. Compared with standard regression-based methods, our framework achieved higher predictive accuracy. We show that scBayesAge is a powerful tool for dissecting the cellular heterogeneity of aging and age-related functional decline.

Age is a major risk factor for various diseases, such as cancer, cardiovascular conditions, and neurodegenerative diseases. However, chronological age, the simple number of years one has lived, does not capture individual health differences, prompting the development of methods to accurately estimate biological age instead of relying on chronological age. One of the major molecular approaches exploits DNA methylation (DNAm), which is an essential epigenetic modifier for regulating gene expression, cell differentiation, and aging. DNAm-based aging clocks have been developed to predict biological age, but the prediction is highly dependent on training data, including organs and assay technologies. To address these clocks' high variance, we present two EnsembleAge clocks, leveraging eight previously developed DNAm clocks, harnessing the strengths of each methylome age clock, smoothing out individual variances, and providing a more robust estimation of biological age. We trained our EnsembleAge clock models using DNA methylation data from nine organs in the Genotype-Tissue Expression (GTEx) dataset. Our EnsembleNaive clock model achieved the lowest median absolute error (MeAE) of 4.04 years in whole blood. The EnsembleLR model demonstrated the lowest MeAE of 6.35 years across multiple tissues, including breast, lung, muscle, ovary, prostate, testis, and colon. The significant reduction in MeAE underscores its high practical value in clinical and forensic applications, especially in contexts where epigenetic changes are subtle. We further applied our models to four public datasets representing diverse biological applications, including administered short-term medical opioid use (GSE151485) and long-term opioid overdose (GSE164822). Our model reveals over 10 years of age acceleration in opioid-overdosed brains but no significant epigenetic age acceleration when opioid usage was well administered. Our EnsembleAge clock models are also implemented as a web service, allowing users to conveniently upload their DNA methylation data and receive predictions of their biological age. This empowers individuals to track their biological/epigenetic age over time, mitigating the effect of variance and promoting healthy aging and a beneficial lifestyle. Our EnsembleAge clock service is available at https://ensemble.epiclock.app/.

Aging of the brain, an intricate process, is a significant risk factor for neurodegenerative disorders (NDDs), such as Alzheimer's disease and Parkinson's disease. Senescent cell accumulation is an important hallmark of brain aging. These cells resist apoptotic cell death, produce proinflammatory cytokines, increase oxidative stress, and store toxic proteins that exacerbate neurodegeneration. These senescent cells cause neuroinflammation and dysfunction of the neuronal microenvironment by transmitting senescent phenotypes to neighboring healthy cells. Senolytics have become a viable treatment option to reduce the effects of brain aging since they specifically target and destroy senescent cells. Numerous senolytic compounds, such as dasatinib, fisetin, and quercetin, effectively eliminate senescent cells and reduce the accumulation of harmful substances, including misfolded toxic protein aggregates and reactive oxygen species, thereby helping to maintain tissue homeostasis. These medications aid in reducing oxidative stress and inflammation, two significant factors in brain aging and NDDs, by encouraging the removal of senescent cells. The key molecules involved in this process are mTOR, Nrf2-Keap1, AMPK, and Sirtuin 1 (SIRT1). The modulation of the mTOR and AMPK pathways affects autophagy and cellular metabolism, facilitating the elimination of harmful accumulations and damaged cell organelles. In addition, cellular repair and improved antioxidant defense are encouraged by the activation of the SIRT1 and Nrf2 pathways. The combination of senolytic therapy with these signaling pathways provides a novel approach to attack the cellular and molecular foundations of brain aging and neurodegenerative disorders.

Skeletal muscle regeneration occurs through the finely timed activation of resident muscle stem cells (MuSC). Following injury, MuSC exit quiescence, undergo myogenic commitment, and regenerate the muscle. This process is coordinated by tissue microenvironment cues, however the underlying mechanisms regulating MuSC function are still poorly understood. Here, we demonstrate that the extracellular matrix protein Tenascin-C (TnC) promotes MuSC self-renewal and function. Mice lacking TnC exhibit reduced number of MuSC, and defects in MuSC self-renewal, myogenic commitment, and repair. We show that fibro-adipogenic progenitors are the primary cellular source of TnC during regeneration, and that MuSC respond through the surface receptor Annexin A2. We further demonstrate that TnC declines during aging, leading to impaired MuSC function. Aged MuSC exposed to soluble TnC show a rescued ability to both migrate and self-renew in vitro. Overall, our results highlight the pivotal role of TnC during muscle repair in healthy and aging muscle.

The insulin/IGF-1 signaling (IIS) pathway is an evolutionary conserved regulator of longevity, and its modulation is a hallmark of aging research. The 1993 ground-breaking report of a daf-2 mutation (e1370) that reduced IIS and doubled C. elegans lifespan in hermaphrodite worms paved the way for molecular approaches to modulating aging. However, the impact of that mutation on the male sex has remained largely unstudied. Here we report that the same mutation extends male lifespan by fourfold, to over 110 days. This extreme longevity is coupled with a dramatic extension of healthspan as well. These findings establish sex not as a secondary variable but as a primary determinant of longevity potential, capable of amplifying the output of a core aging pathway to an astonishing degree. This work provides a new approach or dissecting the interplay between sex and aging and suggests that sex-specific interventions may be critical for developing future anti-aging therapeutics.

Lysosomes are critical hubs for both cellular degradation and signal transduction, yet their function declines with age. Aging is also associated with significant changes in lysosomal morphology, but the physiological significance of these alterations remains poorly understood. Here, we find that a subset of aged lysosomes undergo enlargement resulting from lysosomal dysfunction in C. elegans. Importantly, this enlargement is not merely a passive consequence of functional decline but represents an active adaptive response to preserve lysosomal degradation capacity. Blocking lysosomal enlargement exacerbates the impaired degradation of dysfunctional lysosomes. Mechanistically, lysosomal enlargement is a transcriptionally regulated process governed by the longevity transcription factor SKN-1, which responds to lysosomal dysfunction by restricting fission and thereby induces lysosomal enlargement. Furthermore, in long-lived germline-deficient animals, SKN-1 activation induces lysosomal enlargement, thereby promoting lysosomal degradation and contributing to longevity. These findings unveil a morphological adaptation that safeguards lysosomal homeostasis, with potential relevance for lysosomal aging and life span.

The contribution of mitochondria to lifespan determination remains controversial, as impaired mitochondrial function can paradoxically both shorten and extend longevity. During ageing, mitochondria accumulate defects that disrupt electron transport and elevate the production of reactive oxygen species (ROS) per unit of ATP. Here, we developed Drosophila melanogaster models carrying mitochondria that phenocopy aged organelles -termed 'aged-like' mitochondria- to dissect the developmental versus adult contributions of mitochondrial dysfunction to lifespan regulation. Inducing aged-like mitochondria during development caused profound metabolic maladaptation and markedly reduced adult lifespan, without signs of accelerated ageing. In contrast, restricting their expression to adulthood resulted in only a modest reduction in lifespan, accompanied by an increased mortality rate, indicative of accelerated ageing. Enhancing mitochondrial function exclusively during development by expressing the alternative oxidase (AOX) mitigated these metabolic defects and significantly extended adult survival. Likewise, developmental overexpression of Rheb, an activator of Target of Rapamycin (TOR) signalling, improved adult survival without restoring mitochondrial respiration. Finally, we show that mitochondrial respiratory capacity cannot be reinstated in adults with 'aged-like' mitochondria, as oxidative phosphorylation (OXPHOS) protein levels are largely established during development and remain stable throughout adult life. We propose that Drosophila permanently tunes adult metabolism according to developmental cues to optimise reproductive fitness, at the expense of long-term survival.

Epigenetic clocks are machine learning models that predict an organism's chronological age (the time elapsed since birth) or biological age (a proxy for physiological integrity) based on methylation levels from multiple genomic sites. To date, all epigenetic clocks rely exclusively on C5-methylcytosine (5 mC), the predominant DNA methylation mark in vertebrates. However, not all species possess detectable 5 mC levels. Here, we used N6-methyladenine (6 mA), a less-characterized DNA modification type, to develop a series of epigenetic clocks in the buff-tailed bumblebee (Bombus terrestris). Using long-read Nanopore sequencing, we generated genome-wide, base-resolution profiles of 6 mA and 5 mC in males of different ages (n = 15), and developed multiple epigenetic clocks based on distinct features of the aging DNA methylome. All clocks showed strong correlations between predicted epigenetic and chronological age. Moreover, they also detected pharmacologically induced lifespan extension, reflected by a reduction in predicted epigenetic age relative to chronological age, indicating that these clocks capture biological aging. These findings demonstrate that 6 mA can be used to build accurate epigenetic clocks and establish 6 mA as a promising biomarker of aging in animals.

Chronic kidney disease (CKD) is a major health issue, with podocyte injury with senescence playing a central role in glomerulosclerosis. This study investigates the link between glycolysis-derived serine metabolism and podocyte injury with senescence, focusing on the role of phosphoglycerate kinase 1 (PGK1) in the regulation of L-serine synthesis and podocyte homeostasis. Using in vivo and in vitro models, we examined the effects of angiotensin II (Ang II)-induced metabolic dysregulation on serine metabolism and its impact on podocyte function. The results demonstrate that Ang II downregulates PGK1 expression through the transcription factor FOXA1, leading to reduced L-serine biosynthesis, mitochondrial dysfunction, and increased cellular senescence in podocytes. Supplementing with L-serine or enhancing PGK1 expression in podocytes alleviated these pathological changes, restored mitochondrial function, and reduced senescence-associated phenotypes in CKD mouse models. Moreover, PGK1 was found to interact with keratin, type II cytoskeletal 1 (KRT1), stabilizing the cytoskeletal integrity of podocytes. These findings identify a novel metabolic pathway linking glycolysis, serine metabolism, and podocyte injury with senescence, suggesting that targeting the PGK1-serine axis may offer therapeutic potential for slowing podocyte senescence and CKD progression.

Aging of the central nervous system (CNS) leads to a progressive decline in numerous physiological functions. This decline can be attributed in part to alterations within the oligodendrocyte lineage, which comprises myelinating oligodendrocytes (OLs) and their progenitors, NG2-glia, that play a central role in maintaining homeostasis and ensuring proper myelin turnover. While NG2-glia are distributed throughout the CNS, OLs are enriched in highly myelinated regions, implying spatially heterogeneous requirements for NG2-glia proliferation and differentiation. Consequently, age-related impairments in these progenitor functions may differentially compromise oligodendrogenesis and myelin maintenance across distinct CNS compartments. Yet, the spatial and temporal dynamics of aging-associated alterations within the oligodendrocyte lineage remains insufficiently characterized. To address this gap, we investigated the effects of aging across three age groups in two anatomically adjacent but functionally distinct CNS regions, the cortical gray matter (GM) and the corpus callosum (CC). We demonstrated that aging is accompanied by a marked decline in the NG2-glia population. Aging NG2-glia displayed cell cycle dysregulation, characterized by reduced proliferative and differentiative capacity and accompanied by increased expression of cyclin-dependent kinase inhibitors (CDKIs), indicating disrupted homeostatic regulation. These alterations were most pronounced in highly myelinated regions, which also exhibited a stronger shift toward an age-associated inflammatory milieu. In parallel, we observed substantial accumulation of myelin debris and impaired phagocytic clearance in these myelin-dense areas. Moreover, we identified a selective loss of myelinating OLs in the CC, a phenomenon not detected in the gray matter (GM). Together, our findings delineate a tight interdependence between regional myelin density, inflammatory status, and the vulnerability of oligodendrocyte lineage cells to aging. These highlight multiple entry points of potential therapeutic intervention to mitigate CNS aging.

Senescent cells are characterized by a stable proliferation arrest and a senescence-associated secretory phenotype or SASP. Although these cells can have some beneficial effects, including protecting from tumor formation, their accumulation is deleterious during aging as it promotes age-related diseases, including cancer initiation and progression. Although the SASP has a critical role, its composition, regulation and dual role in cancer remain largely misunderstood. Here, we show that ANGPTL4 is one of the rare secreted factors induced in many different types of senescent cells. Importantly, ANGPTL4 knockdown during senescence or its constitutive expression, respectively inhibits or induces classical proinflammatory SASP factors, such as IL1A, IL6 and IL8. The latter effect is mediated upstream of IL1A, an early SASP factor, suggesting an upstream role of ANGPTL4 in SASP induction. This ANGPTL4-dependent proinflammatory SASP can promote human neutrophil activation in ex vivo assays, or tumor initiation in a KRAS-dependent lung tumorigenesis model in mice. This upstream activity of ANGPTL4 in regulating the proinflammatory SASP depends on its upregulation following a hypoxia-like response and HIF2A activation, and its proteolytic processing by the FURIN proprotein convertase. Altogether these findings shed light on a two-step activation of ANGPTL4 by HIF2A and FURIN in senescent cells and its upstream role in promoting the proinflammatory SASP, cancer and potentially other senescence-associated diseases.

There is still relatively little known about the genetic underpinnings of proteomic aging clocks. Here, we describe a genome-wide association study of proteomic aging in the UK Biobank (n=38,865), identifying 27 loci associated with participants' proteomic age gap (ProtAgeGap). ProtAgeGap exhibits a strong genetic correlation with longevity (rg = -0.83), and in FinnGen a ProtAgeGap polygenic score (PGS) was associated with significantly increased odds of achieving longevity (n=500,348; OR = 1.43). Additional PGS analyses in All of Us (n=117,415), China Kadoorie Biobank (n=100,640), and ABCD Study (n=5,204) demonstrate reproducible associations across biobanks of ProtAgeGap PGS with obesity, cardiometabolic disease, and osteoarthritis in adults, and with developmental timing in children. Finally, colocalization analysis identified FTO as an obesity-related mechanism uniting diverse aging traits. Our results demonstrate a shared genetic architecture across the life course of ProtAgeGap with longevity, early developmental biology, and cardiometabolic and musculoskeletal diseases.

Major depressive disorder (MDD) is linked to a higher risk of premature aging, but the mechanisms underlying this association remain unclear. Using data from two population cohorts (UK Biobank and Finnish Twin Cohort), we evaluate the relationship between systemic and organ-specific proteomic and epigenetic aging acceleration and MDD. A lifetime history of MDD was associated with accelerated proteomic aging at both systemic and organ-specific levels-including the brain-in both cohorts, with stronger associations than those observed with systemic epigenetic aging. Systemic and brain-specific proteomic aging acceleration were linked to higher risks of incident MDD and a greater risk of Alzheimer's disease, related dementia, and mortality among individuals with MDD in the UK Biobank. Evidence of depressive episode remission attenuated the association between MDD and systemic and brain-specific proteomic aging acceleration. Finally, Mendelian randomization analyses revealed a causal effect of MDD on systemic and brain-specific proteomic aging acceleration. Our results suggest a strong bidirectional association between MDD and biological aging acceleration. Biological aging acceleration, assessed by proteomic systemic and organ-specific clocks, can serve as a novel therapeutic target for treating MDD and for mitigating the long-term risks of adverse health outcomes associated with this condition.

Vascular endothelial cells (ECs) are pivotal in maintaining vascular homeostasis. Liraglutide (LIR) can prevent and reverse hyperglycemia-induced cell dysfunction. However, the mechanism by which it improves hyperglycemia-induced EC senescence remains unclear. This study investigates whether the La Ribonucleoprotein 7/Sirutin 1 (LARP7/SIRT1) signaling axis is essential for LIR efficacy in mitigating EC senescence and dysfunction. We treated senescent human umbilical vein ECs induced by high glucose levels with LIR and evaluated cell viability cell counting kit-8 (CCK-8 assay), senescence (SA-β-gal staining), and SASP alterations (qPCR). We also investigated the expression of senescence-related proteins and changes in the LARP7/SIRT1 signaling pathway using Western blot analysis. Additionally, reactive oxygen species levels were measured with 2',7'-Dichlorodihydrofluorescein diacetate (DCFH-DA), and changes in oxidative stress-related factors were assessed using specific assay kits. The effect of LIR on endothelial dysfunction was examined by cellular tube-forming assay and transwell assay after LARP7 knockdown/overexpression. LIR markedly improved cell vitality and the senescence phenotype while reducing oxidative stress. The LARP7/SIRT1 pathway emerged as crucial for its effectiveness. Following LARP7 knockdown, the therapeutic efficacy of LIR was notably attenuated. The overexpression of LARP7 enhanced the therapeutic efficacy of LIR. The tube formation and transwell assays further supported the hypothesis that LIR's beneficial impact on endothelial dysfunction depends on the LARP7/SIRT1 signaling axis. Our study reveals a novel aspect of LIR as an antidiabetic agent in delaying vascular aging driven by high glucose through targeting the LARP7/SIRT1 pathway. This discovery enhances the therapeutic value of LIR and proposes a new strategy for addressing vascular aging in treatments for elderly patients with diabetes.

Aging profoundly alters the bone marrow (BM) microenvironment and impairs hematopoietic stem cell (HSC) function. Here, we identify decrease of miR-126 derived from arteriolar endothelial cells (ECs) as a key mechanism of impaired HSC self-renewal capacity during aging. In young BM, arteriolar ECs express high levels of miR-126, which is transferred to HSCs and supports these cells' homeostasis and functional integrity. Using young and aged wild-type, endothelial-specific miR-126 knockout (EC-miR-126 KO), EC-Spred1 knockout (a functional model of EC-miR-126 upregulation), and EC/Sca-1 dual fluorescent reporter mice, we show that age-related increase in inflammatory cytokines (such as TNFα) reduces EC miR-126 expression and in turn drives loss of miR-126high CD31+Sca-1high EC-lined arterioles in the aging BM niche. Loss of arterioles in turn decreases the EC miR-126 supply to HSCs, leading to expansion of HSCs with limited self-renewal capacity. Remarkably, administration of a synthetic miR-126 mimic oligonucleotide restores EC-HSC communication and rescues aging-related HSC dysfunction. Our findings uncover a novel, non-cell-autonomous mechanism of HSC aging and highlight EC-derived miR-126 as a promising therapeutic target to rejuvenate hematopoiesis.

PARP1, a poly-ADP-ribose transferase, plays a critical role in maintaining genomic stability, transcription, cellular metabolism, and cell death. PARP1 inhibition protects cardiomyocytes against oxidative and genotoxic stress. However, the role of PARP1 in aging-associated heart failure remains poorly explored. In the current study, we report that PARP1 levels are downregulated in aging mouse hearts, and PARP1 deficiency induces aging-related cardiac remodelling and contractile dysfunction in mice. PARP1 deficient mice hearts exhibit spontaneous activation of the Akt signalling pathway, leading to the development of aging-related cardiac hypertrophy and fibrosis. Our findings reveal two distinct mechanisms by which PARP1 regulates Akt signalling, direct interaction of PARP1 with Akt and the transcriptional regulation of phosphatases like PTEN, a negative regulator of Akt signalling. PARP1 binds and inhibits Akt by poly-ADP-ribosylation at E40 and E49 residues, which impairs Akt membrane recruitment and subsequent activation. Inhibition of Akt reversed hypertrophy in PARP1-depleted cardiomyocytes and improved the contractile dysfunction in PARP1-deficient hearts. These findings reveal a previously unrecognized regulatory role for PARP1 in aging-associated cardiac failure.

N6-methyladenosine (m6A) is the most common reversible mRNA modification, regulating fundamental cellular processes. It plays a vital role in aging and age-related diseases by influencing gene expression, RNA splicing, and stability. Growing evidence suggests that m6A modifications orchestrate key hallmarks of aging, including cellular senescence, stem cell exhaustion, and chronic inflammation factors that contribute to neurodegeneration, cardiovascular disease, and cancer. The intricate crosstalk between m6A and chromatin modifications is now recognized as a fundamental mechanism shaping age-associated epigenetic landscapes and influencing disease susceptibility. Core m6A regulators, such as METTL3, FTO, and ALKBH5, are implicated in age-related metabolic decline, neurodegeneration, and impaired tissue regeneration, making them promising therapeutic targets. Dysregulated m6A patterns are linked to aberrant RNA metabolism, protein aggregation, and synaptic dysfunction in Alzheimer's and Parkinson's diseases, while in cardiovascular and metabolic disorders, m6A modifications contribute to endothelial dysfunction, inflammation, and oxidative stress. Recent breakthroughs in computational modeling and RNA-editing technologies have revolutionized m6A research. High-precision deep-learning models (e.g., m6A-DCR) and CRISPR-based m6A editing tools provide powerful platforms to decode m6A's role in aging and disease progression. These advances pave the way for novel therapeutic strategies, offering opportunities for early diagnostics, precision medicine, and personalized interventions. Despite these promising developments, challenges remain in translating m6A-targeted therapies into clinical applications. Future research must enhance treatment specificity, minimize off-target effects, and elucidate the broader implications of m6A in aging. Advancing our understanding of m6A's functional landscape is essential for developing next-generation RNA-based therapeutics to combat aging and its associated diseases.

Brain aging is a major factor in cognitive decline and Alzheimer's disease (AD) progression. Aging-induced microglial senescence critically drives inflammaging and brain aging processes. Nevertheless, the underlying reasons and mechanisms that promote microglial aging remain unclear. This study explores how 27-hydroxycholesterol (27-OHC), a key oxysterol, accelerates brain aging by promoting microglial senescence, iron overload, and neuroinflammation. Clinically, we observed a significant inverse correlation between plasma 27-OHC levels and Mini-Mental State Examination (MMSE) scores in AD patients, accompanied by reduced 24S-OHC concentrations. Experimental studies revealed that 27-OHC administration in mice induced hippocampal-dependent cognitive impairment and anxiety-like behaviors, concurrent with elevated expression of cellular senescence markers (P21, P16, SA-β-Gal) and M1 microglial polarization. In BV-2 cells, 27-OHC disrupted iron homeostasis (DMT1/ferritin/GPX4 dysregulation), elevating ROS and impairing mitochondrial function. Deferoxamine (DFX) mitigated microglial senescence and ferroptosis. These findings establish the 27-OHC-iron axis as a novel therapeutic target for combating cholesterol-driven neurodegeneration.

Chaperone-mediated autophagy (CMA) contributes to proteostasis maintenance by selectively degrading a subset of proteins in lysosomes. CMA declines with age in most tissues, including skeletal muscle. However, the role of CMA in skeletal muscle and the consequences of its decline remain poorly understood. Here we demonstrate that CMA regulates skeletal muscle function. We show that CMA is upregulated in skeletal muscle in response to starvation, exercise and tissue repair, but declines in ageing and obesity. Using a muscle-specific CMA-deficient mouse model, we show that CMA loss leads to progressive myopathy, including reduced muscle force and degenerative myofibre features. Comparative proteomic analyses reveal CMA-dependent changes in the mitochondrial proteome and identify the sarcoplasmic-endoplasmic reticulum Ca

Background: Leucine Rich Repeat Containing 8A (LRRC8A) anion channels (VRACs) associate with NADPH oxidase 1 (Nox1) and support extracellular superoxide (O2*-) production, inflammation, and contractility in vascular smooth muscle cells (VSMCs). We proposed previously that VRACs also support influx of O2*- to produce localized cytoplasmic signaling. Methods: We assayed O2*- influx, and guided by changes in mRNA expression (RNAseq) tested multiple phenotypes of cultured LRRC8A knockout (KO) VSMCs. Aortic atherosclerotic burden and inflammation, and mesenteric vascular reactivity were compared between wild type (WT) apolipoprotein E null (ApoE-/-) mice and VSMC-specific LRRC8A KO, ApoE-/- mice. Results: KO cells were less permeable to extracellular O2*-, produced less mitochondrial O2*-, and experienced less oxidant stress (GSH/GSSG, lipid peroxidation, Nrf2 activity) than WT. RNAseq and reporter assays demonstrated reduced pro-inflammatory (NF-{kappa}B and Hif1) transcription. KO cells also under-expressed multiple senescence markers and had longer telomeres. Inflammation causes a metabolic shift from oxidative phosphorylation (OCR) to glycolysis (ECAR). Both pathways were less active in KO cells, as was expression of glycolytic enzymes. Mitochondrial membrane potential was lower in KO cells, but ADP/ATP and NADP+/NADPH were unaltered, suggestive of lower energy demand. Consistent with this, proliferation and migration were both reduced in KO cells. Protein-protein interaction analysis of RNAseq (PPI Hub) identified the Epidermal Growth Factor Receptor (EGFR) signaling pathway. Activating phosphorylation of EGFR (Y1068) as well as downstream AKT (S473 and T308) were reduced. Following 15 weeks of exposure to a high fat diet (42%) VSMC-specific LRRC8A-/- and 8A+/-, ApoE-/- mice had less atherosclerotic lesion area, and reduced aortic senescence ({beta}-Gal), inflammation (ICAM, VCAM) and proliferation marker (PCNA) expression. Mesenteric artery vasomotor function was also preserved compared to WT, ApoE-/- controls, and the abundance of MYPT1 and CPI17 was lower in KO vessels. Uptake of oxidized LDL (OxLDL) was significantly reduced in KO VSMCs and similarly impaired by VRAC block in WT cells. Conclusions: Loss of LRRC8A reduces O2*- influx, oxidative stress, inflammation and senescence, lowers energy demand, and in the setting of hypercholesterolemia impairs uptake of oxidized LDL and abrogates atherosclerosis. VRAC inhibitors warrant further investigation as therapeutic vascular anti-inflammatory agents.

Biological brain ageing is a major risk factor for neurodegenerative diseases, which are characterized by selective degeneration of particular neuron types. We analyzed the impact of ageing on the transcriptome of neurons in the ventral tegmental area (VTA), substantia nigra pars compacta (SNc) and locus coeruleus (LC), that show differential vulnerabilities to Parkinson disease. Neurons were isolated from human post mortem brain tissues originating from 48 individuals ranging from 17 to 102 years of age and subjected to Smart-seq2 RNA sequencing. We identified 2,764 genes that were correlated with chronological ageing. This gene expression data was used to develop a feature selection-based Time Traversal algorithm, utilizing functionally grouped gene sets, GO terms, with high predictive accuracy of biological brain ageing. We identified 59 GO terms that can predict biological age using a linear regression model, where leave-one-out cross validation demonstrated a strong correlation between chronological age and predicted biological age (Pearson correlation coefficient = 0.946; adjusted R2 = 0.771). The algorithm was validated on five independent datasets with high predictive performance, demonstrating shared ageing features across the human brain. Nonetheless, our analysis also highlights brain region and neuron type specificity in particular ageing features. Resilient neurons showed a weaker association with age-related transcriptional changes, indicating that they age slower than their vulnerable counterparts, thus revealing targets that may be used to slow down ageing and prevent disease development.

Background: Cognitive training aims to prevent or slow cognitive decline in older adults, but outcomes vary widely. Engagement, describing how individuals allocate cognitive, affective, and physiological resources, is critical to training benefits, yet behavioral metrics lack real-time modeling of attention and do not reliably predict outcomes. We developed and validated a multimodal, AI-assisted biomarker that quantifies attentional states during computerized cognitive training and predicts cognitive improvements. Methods: We designed the Attentional Index using Digital measures (AID), leveraging a video-based facial expression encoder (pretrained on 38,935 videos), an ECG-based autonomic encoder (pretrained on 123,998 ECG samples), and a temporal fusion module. Using two processing speed/attention studies in older adults (> 65 years) with mild cognitive impairment, AID was trained and evaluated in BREATHE (n=50; ~300 hours from 368 sessions) and validated in FACE (n=20; ~150 hours from 219 sessions). Model training targeted session-level change in self-reported fatigue. Clinical validation tested relationships between AID scores and (1) behavioral attention, (2) cognitive outcomes, and (3) neural correlates. Findings: AID accurately detected engagement changes (BREATHE: accuracy 0.82, F1=0.81; FACE: accuracy 0.73, F1=0.74), outperforming unimodal models. AID scores were unrelated to session, task type, or demographics. In BREATHE, session-level AID scores significantly predicted executive function improvement (sessionxAID: Wald^2=7.85, p=0.005), whereas reaction time variability did not. Lower AID intercepts (B=-0.07{+/-}0.03, p=0.043) and steeper slopes (B=0.31{+/-}0.15, p=0.046) were associated with greater improvements. Post hoc analyses identified two engagement profiles linked to better attention: one characterized by low-RMSSD and focused periocular activation, and the other defined by coherent alignment between low-RMSSD and facial expression patterns. Interpretation: AID provides a reliable digital biomarker of effective engagement and predicts cognitive improvement beyond behavioral metrics. By capturing facial-autonomic dynamics of attention, AID offers a foundation for closed-loop cognitive intervention design. Funding NIH AG081723, NR015452, and AG084471; Stanford HAI seed funding.

Mesenchymal stem cells (MSCs) hold great promise in cell therapy, but their effectiveness declines with repeated cell divisions due to senescence. Canines, sharing aging characteristics with humans, serve as a valuable model to study this process in a translational context. In the present study, we performed an in-depth characterization of senescence in canine MSCs using a combination of morphological, molecular, and transcriptomic analyses. Early (P2) and late-passage (P6) canine MSCs were characterized using a combination of senescence-associated β-galactosidase staining, cell cycle profiling, and both bulk and single-cell RNA sequencing to capture global transcriptional changes. By employing a passage-based in vitro approach, the present study demonstrates that late-passage cells (P6) compared to early-passage cells (P2) exhibit hallmark features of senescence, including morphological alterations, elevated SA-β-galactosidase activity, and considerable transcriptional changes. These changes were represented by significant upregulation of established senescence marker genes, alongside potential novel candidates and downregulation of genes associated with cell cycle progression and proliferation. Moreover, single-cell RNA sequencing uncovered heterogeneous distribution of senescent subpopulations, upregulation of SASP-related genes and reduced proliferation markers. Our findings demonstrate that combining classical markers with bulk and single-cell RNA sequencing facilitates senescent cell identification while improving quality control for clinical MSC samples.

The SARS-CoV-2 pandemic has affected millions worldwide, with aging being a key risk factor for severe disease outcomes. This study examines the rate of epigenetic aging, as measured by DNA methylation-based aging markers, in COVID-19 patients versus healthy individuals. We found that PCGrimAge, a next-generation epigenetic clock associated with immune dysregulation and inflammation, showed the strongest correlation with the chronological age of the European COVID-19 patients. Several other next-generation epigenetic clocks, including PCGrimAge, DunedinPACE, and ZhangY2017, also exhibited accelerated aging in both older and female COVID-19 patients. Interestingly, first-generation clocks, such as Hannum2013, indicated a significant reduction in epigenetic aging, likely reflecting limitations in their sensitivity to infection-related biological changes rather than an actual deceleration of the aging process. Our results also showed that immune dysregulation, rather than intrinsic cellular aging, may be the primary driver of accelerated epigenetic aging in COVID-19. This is supported by stronger associations observed in Age Acceleration (AA) and Extrinsic Epigenetic Age Acceleration (EEAA) compared to Intrinsic Epigenetic Age Acceleration (IEAA). Furthermore, immune dysregulation may be linked to CpG site demethylation, which in turn influences epigenetic clock dynamics. We also identified disparities between European and non-European populations, characterized by significantly higher IEAA for PCPhenoAge and DunedinPACE among non-European patients with COVID-19. In summary, our results underscore the differential sensitivity of epigenetic clocks to COVID-19-related biological changes.

We analyze 10,986 participants (mean age 77; 63% women; 54% non-White) across seven U.S. cohorts to study the relationship between mitochondrial DNA (mtDNA) heteroplasmy and nuclear DNA methylation. We identify 597 CpGs associated with heteroplasmy burden, generally showing lower methylation. These CpGs are enriched in dynamically regulated island shores and depleted in CpG islands, indicating involvement in context-specific rather than constitutive gene regulation. In HEK293T cells, we introduce a truncating mtDNA mutation (MT-COX3, mt.9979) and observe a positive correlation between variant allele fraction and methylation at cg04569152, supporting a direct mtDNA-nDNA epigenetic link. Many heteroplasmy-associated CpGs overlap with known methylation-trait associations for metabolic and behavioral traits. Composite CpG scores predict all-cause mortality and incident CVD, with one-unit increases associated with 1.27-fold and 1.12-fold higher hazards, respectively. These findings suggest an mtDNA-nDNA epigenetic connection in aging and disease, though its direction and mechanisms remain to be studied.

Irisin, a myokine released by skeletal muscle during physical activity, has emerged as a key regulator of energy metabolism, cellular stress responses, and longevity pathways. While previous studies have focused on aged animal-models or pathological states, the long-term impact of early-life interventions on molecular aging pathways remains poorly understood. This study investigated whether early-life irisin administration and physical exercise could modulate the renal-expression of Klotho and HSP70-two hallmark genes of cellular protection and anti-aging in young adult NMRI mice. Animals underwent 8 weeks of resistance training, endurance training, or irisin injection. Plasma irisin was quantified via ELISA, and renal Klotho and HSP70 expression levels were assessed using qPCR and Western-blotting. All interventions significantly increased circulating irisin and upregulated Klotho and HSP70 at both transcriptional and protein levels, with resistance training inducing the most pronounced effects. A 20-month survival analysis showed a trend toward improved longevity in all intervention groups. These findings suggest that early-life exercise and irisin exposure may activate renoprotective and longevity-associated pathways before the onset of molecular aging, supporting their potential as preventive strategies in translational geroscience.

Aging humans and non-human primates both exhibit a similar pattern of cognitive decline beginning in middle age that is characterized by progressive impairments in rule learning, executive function, and working and recognition memory-functions often associated with dysfunction of prefrontal and medial temporal lobe regions. The heterogeneity and inter-subject variability in aging and age-related cognitive impairments present challenges for developing effective therapeutics and can be attributed to differing degrees of cortical white matter (WM) damage and alterations to local and long-range prefrontal and temporal networks. A promising therapeutic that has been shown to be efficacious in mitigating WM damage and improving cognitive function in rodent models is mesenchymal cell-derived extracellular vesicles (MSC-EVs). In the present study, late middle-aged rhesus monkeys were systemically administered monkey-derived MSC-EVs every 2 weeks for 18 months. We demonstrate that MSC-EV treatment improves spatial working memory and decreases the frequency of perseverative responses with largely no effects on recognition memory. These cognitive improvements were associated with increases in MRI diffusion measures of WM structural integrity over time as well as preservation of inter-network functional connectivity as measured by resting-state functional MRI. These findings suggest that MSC-EV treatment can slow or reverse age-related cognitive decline while strengthening WM integrity and improving functional connectivity in late middle-aged rhesus monkeys.

Metabolic and genetic abnormalities have long been noted in cardiovascular diseases, but the contribution of mitochondrial genetic (mitochondrial DNA [mtDNA]) variation is understudied. Mitochondrial genetics is complex in that each mitochondrion contains multiple mtDNA copies that may carry different variants, which is called heteroplasmy. Heteroplasmic variation is dynamic, increases with advancing age, and may contribute to aging-related cardiovascular diseases. Pathogenic variants in mitochondrial genes of the mtDNA or nuclear genome cause mitochondrial diseases, often with cardiac involvement, particularly in patients with adult-onset disease. Population-level studies have identified mtDNA variants associated with cardiovascular risk factors and disease, but evaluation of mtDNA genetic variation is often limited to only a handful of variants and small sample sizes. Studies in animal models have linked several mtDNA variants to cardiac remodeling and dysfunction and suggest a role for mitochondrial-nuclear genetic interactions in disease penetrance. The objective of this scientific statement is to outline the current state of understanding of the role of mitochondrial genetics in cardiovascular pathobiology and highlight important gaps in knowledge. The intended audience of this scientific statement is meant to be broad, spanning clinical, translational, and basic researchers and health care professionals. Despite remaining limitations and barriers, recent advances in genomic sequencing, mtDNA gene editing modalities, and the directed differentiation of stem cells to cardiovascular cell types are creating new opportunities to advance understanding of mitochondrial genetics in cardiovascular pathophysiology.

Background Phosphatidylinositol transfer protein-1 (pitp-1) is involved in phosphoinositide turnover. The role of pitp-1 in promoting healthy longevity remains unknown. Our previous work showed that the phosphoinositide turnover genes dagl-1 and dgk-5 regulates lifespan, as overexpression of dagl-1 or knockdown of dgk-5 prolongs lifespan and enhances oxidative stress resistance through TOR signaling. As pitp-1 is a key component of this pathway, we investigated its role in lifespan regulation and the underlying mechanisms, aiming to clarify whether it represents a critical regulator of healthy longevity and how it coordinates conserved signaling pathways to regulate aging. Methods C. elegans mutants, RNAi-mediated knockdown, and transgenic overexpression were applied to assess lifespan, motility, stress resistance. Temporal and tissue-specific RNAi were applied to identify the critical time window and tissue for pitp-1-mediated lifespan regulation. TOR signaling was measured by phosphorylated S6 kinase and puromycin incorporation, and transcriptomic analysis identified affected pathways. Results pitp-1 negatively regulates lifespan and healthspan in Caenorhabditis elegans. Genetic deletion or RNAi-mediated knockdown of pitp-1 extends lifespan, attenuates age-related motility decline, and increases oxidative stress resistance. Temporal and spatial analyses reveal that suppression of pitp-1 in neurons during early adulthood is sufficient to promote healthy longevity. Mechanistically, these beneficial effects upon pitp-1 reduction are mediated by suppressing TOR signaling. Conversely, pitp-1 overexpression shortens lifespan and impairs healthspan via TOR activation. Moreover, pitp-1 is transcriptionally repressed by DAF-16 downstream of insulin/IGF-1 signaling (IIS), and contributes to IIS-mediated lifespan extension. Conclusion These findings identify pitp-1 as a novel regulator of healthy aging that integrates IIS and TOR pathways, providing new insights into conserved mechanisms for promoting healthy longevity.

The hippocampus plays a central role in episodic memory and has been the focus of extensive research over past decades. A substantial body of work has demonstrated that age-related memory decline is linked to changes in how the hippocampus functionally interacts with distributed brain networks. While functional connectivity changes in ageing are well documented, relatively little is known about alterations in the structural connectivity (SC) of the hippocampus, despite its foundational role in supporting communication across neural systems. In this study, we combined high-quality data from the Human Connectome Project and advanced diffusion-weighted imaging (DWI) methods to investigate age-related changes in hippocampal SC. Using a recently developed tractography pipeline that allows greater anatomical specificity than conventional approaches, we systematically compared connectivity patterns between younger (26-30 years) and older (56-60 years) adults. Results revealed reduced hippocampal SC with the entorhinal cortex and medial parietal cortices in older participants, alongside increased SC with anterior temporal areas. This paradoxical pattern suggests that ageing is associated with both vulnerability and reorganisation of hippocampal networks, with increased hippocampal-temporal connectivity potentially reflecting compensatory plasticity in response to reduced posterior medial connection. These findings provide in vivo evidence of cortico-hippocampal structural reorganisation in late middle age, a critical period when pathological processes such as tau deposition are already detectable in cognitively healthy individuals. More broadly, they demonstrate the power of our anatomically refined tractography pipeline as a proof of concept for detecting subtle, regionally specific changes in hippocampal pathway density. This approach holds promise for charting normative ageing trajectories and identifying early biomarkers of vulnerability and compensation in memory-related networks.

Assessing aging pace through biological age offers a precise perspective and underscores the need for further investigation into organ-level disparities.

Sarcopenia is a progressive age-related condition characterized by the decline of skeletal muscle mass and function. Its development involves multiple cellular and molecular mechanisms, including chronic inflammation, apoptosis, mitochondrial dysfunction, and impaired muscle regeneration. Human umbilical cord mesenchymal stromal cells (HUC-MSCs) have emerged as a promising therapeutic strategy due to their potent immunomodulatory properties, paracrine effects, and ability to promote tissue repair. The regenerative potential of HUC-MSCs is largely mediated by the secretion of bioactive factors that suppress apoptosis, attenuate inflammation, enhance angiogenesis, and remodel the extracellular matrix, thereby establishing a microenvironment conducive to muscle regeneration. Nevertheless, challenges such as limited cell survival, differentiation efficiency, and long-term integration within host muscle, as well as variability in cell sources, delivery routes, and host immune responses, continue to constrain their clinical translation. In this review, we systematically summarize the biological characteristics of HUC-MSCs, their interactions with inflammatory and catabolic pathways in atrophic muscle, and their regulation of key signaling mechanisms involved in muscle repair. We also discuss current limitations and highlight future strategies-such as cellular preconditioning, biomaterial-assisted delivery systems, optimized transplantation protocols, and emerging organ-on-a-chip technologies-to enhance therapeutic efficacy and accelerate clinical application.

Traditional epigenetic aging clocks are limited because they do not incorporate clinical information and functional tests, and rely on DNA samples and methylation profiling infrastructure which are not easily accessible. To address these limitations, we built a new framework, FusionAge, with which we trained 26 aging clocks using interpretable nonlinear models, including deep neural networks (DNNs). Our results show that multimodal clocks built with DNNs significantly outperform clocks derived from single modalities or traditional linear models. FusionAge-derived biological age is more strongly associated with incident disease and mortality compared to chronological age in UK Biobank individuals. We validated these findings in the National Health and Nutrition Examination Survey, confirming that cardiorespiratory fitness is a major, consistent driver of biological age. Finally, we applied FusionAge to demonstrate its utility in detecting biological age changes in astronauts following spaceflight. Together, we demonstrate a powerful, portable framework for assessing biological age that captures the complex, multifactorial nature of human aging.

Cellular reprogramming with transient OSKM expression can reverse aging phenotypes, but genetic factor delivery introduces heterogeneous expression, reprogramming-associated stress, and barriers for therapeutic use. Small-molecule chemical reprogramming is an alternative, yet its performance relative to genetic approaches in human cells is unresolved. We directly compared a human-optimized chemical reprogramming protocol with doxycycline-inducible OSKM in progerin-induced aged fibroblasts and primary fibroblasts from donors over 85. Both reprogramming methods reduced senescence, mitochondrial ROS, and age-associated gene expression, with chemical reprogramming matching or exceeding OSKM efficacy. The two approaches, however, followed distinct trajectories. OSKM generated heterogeneous populations, including subsets acquiring pluripotency markers while others retained fibroblast identity. Chemical reprogramming produced uniform CD13-low populations without pluripotency marker induction. OSKM induced acute senescence that required a chase period to resolve, whereas chemical reprogramming lowered senescence during active treatment. In old fibroblasts, chemical reprogramming reversed multiple aging hallmarks while preserving fibroblast identity and avoiding telomerase activation. These results show that human-optimized chemical reprogramming can rejuvenate aged human fibroblasts with comparable efficacy to OSKM while generating more homogeneous outcomes and lower cellular stress, supporting small-molecule approaches as promising avenues for therapeutic rejuvenation.

Cell-free DNA (cfDNA) methylation sequencing holds promise for developing epigenetic aging clocks. However, current clocks - primarily trained on array-based data - do not readily generalize to high-throughput sequencing (HTS) cfDNA profiles. Using datasets with technical replicates encompassing HTS data from both cfDNA and gDNA, alongside gDNA methylation array data, we systematically assessed factors influencing clock accuracy and reproducibility. We identified key strategies to overcome HTS-specific challenges: maintaining [≥]10x mean target depth, applying elastic net regression with strong L2 regularization, and imputing unreliable beta-values. Transfer learning further enhanced accuracy robustly across multiple independent cohorts. Our findings demonstrate that array-derived epigenetic clocks can be effectively adapted to cfDNA sequencing data. This work offers critical methodological insights and practical guidelines, advancing the feasibility of minimally invasive aging assessment using cfDNA.

Accumulation of senescent cells promotes ageing and age-related diseases. While senescent cells are heterogenous and increasingly persistent in vivo with age, the mechanisms underlying their heterogeneity, resistance to apoptosis, and tissue accumulation remain insufficiently understood. Here we report that in response to DNA damage, a subset of senescent cells upregulates the v-type ATPase subunit, ATP6V1B2 (V1B2) on the cell surface. This upregulation is associated with altered lysosomal activity and changes in intracellular pH. Heterogeneity of senescent cells marked by cell surface V1B2 (csV1B2) is present in naturally occurring senescent cells within both ageing and fibrotic lungs. Senescent cells expressing csV1B2 show an age-independent transcriptional signature associated with DNA repair and resistance to apoptosis. Consistent with this, we show that csV1B2 expression correlates with senescent cell resistance to ABT-737-induced apoptosis in culture. Our study identifies a subset of senescent cells, marked by csV1B2, with a distinct signature of apoptosis resistance. Understanding the functional heterogeneity of senescent cells and the mechanisms accountable for persistence of specific subpopulations in tissues may facilitate the development of improved senotherapeutic strategies for age-related diseases.

Obstructive sleep apnea (OSA) and consequent intermittent hypoxia (IH) is increasingly recognized as a driver of adipose tissue dysfunction, insulin resistance, and aging. However, current in vitro experimental models inadequately capture the long-term effects of IH on human adipocytes. Here, we report the development and optimization of a robust long-term human adipocyte organoid culture system that faithfully recapitulates IH-induced adipocyte aging in vitro. Human stromal vascular fraction (SVF) cells, isolated from subcutaneous abdominal fat biopsies, were embedded in Matrigel and seeded into Biofloat U-bottom 96-well plates. Using a 1:1 Matrigel-cell mixture and optimized seeding volumes (5-20 uL), we established adipocyte organoids that formed within 10-12 days and remained viable with stable morphology for up to 90 days or more. Matrigel was essential for organoid integrity, while alternative matrices such as gelatin and low-melting agarose failed to support proper organoid formation. Subcutaneous preadipocyte medium with 10% FBS from ZenBio was superior to \"Advanced/F12K\" medium for adipogenic differentiation and long-term maintenance. To model OSA-related hypoxic stress, we exposed organoids to intermittent hypoxia using a programmable hypoxia chamber. IH treatment suppressed adipogenesis, as shown by reduced lipid accumulation, downregulation of adipogenic markers (e.g., PPARG, adiponectin, FABP4), and smaller intracellular lipid droplets. Transmission electron microscopy (TEM) revealed IH-induced structural abnormalities, including ER fragmentation, mitochondrial disruption, nuclear enlargement, and heterochromatin formation, all of which are hallmarks of cellular aging. Furthermore, IH upregulated HIF1A, H2AX, and aging-associated histone methylation markers (H3K9me3, H3K79me3, H4K20me3), as well as extracellular matrix remodeling proteins such as fibronectin and LOX. Insulin signaling was also impaired, evidenced by decreased phosphorylation of PI3K and AKT. Collectively, these results establish a reliable platform for long-term human adipocyte organoid culture and demonstrate its utility in modeling IH-induced adipocyte dysfunction and aging. This system offers a physiologically relevant tool for mechanistic studies and preclinical therapeutic screening targeting hypoxia-related metabolic disorders. Keywords: Human adipocyte organoids; intermittent hypoxia; OSA; cellular aging; fat organoid aging model.

Skin aging is driven by both extrinsic factors, such as daily ultraviolet (UV) exposure, and intrinsic processes, including oxidative stress, inflammation, and glycation. Plant-derived medicinal agents and supplements hold promise as interventions against skin aging due to their anti-inflammatory and antioxidant properties. Grape seed extract (GSE), a polyphenol-rich natural product, has demonstrated skin health benefits and is commonly incorporated into various skincare formulations. However, its efficacy and underlying mechanisms, particularly in addressing both intrinsic and extrinsic aging factors, remain incompletely understood. Procyanidin C1 (PCC1), a B-type trimeric procyanidin found in GSE, possesses senolytic properties and has been shown to extend both lifespan and health span in mice. In this study, a newly processed PCC1-rich GSE, named NSPCC1, was evaluated against UV- and d-galactose (d-gal)-induced skin aging in a mouse model. NSPCC1 supplementation mitigated skin cell death, collagen degradation, and structural atrophy while partially restoring skin elasticity and hydration. It also enhanced antioxidant defenses in serum and skin tissues. RNA sequencing revealed that NSPCC1 modulates the MAPK and AMPK pathways, counteracting their dysregulation observed in aged skin. These findings highlight the potential of NSPCC1 to combat skin aging, providing an alternative strategy for skincare interventions targeting both extrinsic and intrinsic aging processes.

Aging is associated with impaired CSF clearance in preclinical models, but its impact on blood-brain barrier (BBB) health and glymphatic function in humans remains unclear. We aimed to compare healthy younger and older adults using multimodal MRI to assess age-related changes in BBB permeability and glymphatic clearance, and to examine the relationships between these measures. Thirty participants were recruited (12 younger, 26 {+/-} 3 years; 18 older, 75 {+/-} 7 years). Diffusion-prepared arterial spin labeling measured the water exchange rate (Kw) across the BBB; free water (FW) imaging quantified extracellular free water in white matter; and diffusion tensor imaging along perivascular spaces (DTI-ALPS) assessed glymphatic function. Older individuals showed reduced whole-brain Kw (p=0.021), increased white matter FW (p=0.002), and reduced DTI-ALPS (p<0.001) compared to younger adults. Kw associated with both DTI-ALPS ({beta}=0.402x10-2, p=0.022) and FW ({beta}=-0.676x10-3, p=0.008). Reduced Kw may reflect impaired BBB function, while reduced DTI-ALPS and increased FW indicate impaired glymphatic clearance. FW partially mediated the relationship between Kw and DTI-ALPS, suggesting a potential mechanistic link. Overall, this study provides novel multimodal MRI insights into BBB and glymphatic alterations in healthy aging and may inform the development of MRI biomarkers to preserve cognitive health.

Cellular senescence can recruit immune cells for tumor therapy through the senescence-associated secretory phenotype (SASP). However, its therapeutic efficacy is limited by immune tolerance and the immunosuppressive tumor microenvironment (TME). Reprogramming tumor-specific senescence through coordinated modulation of P16

Aging, characterized by a gradual decline in physiological function, is a major risk factor for chronic diseases. White tea, one of China's traditional tea types, exhibits various health benefits due to its unique chemical composition, with its anti-aging potential drawing increasing attention. Gallic acid (GA), one of the important bioactive components in white tea, possesses antioxidant and anti-inflammatory properties, but its anti-aging mechanisms remain unclear. In this study, high-performance liquid chromatography was used to analyze the evolution of GA content and to determine the antioxidant capacity of aged white tea. Results revealed that the GA content increased with storage time, accompanied by a corresponding enhancement in the antioxidant potency composite index (APC). Network pharmacology predicted 40 potential anti-aging targets of GA, and protein-protein interaction network analysis identified six key targets (MAOA, PTGS2, BCL2, APP, IGF1R, SERPINE1). Functional enrichment analysis indicated that the anti-aging effects of GA are mediated through multiple pathways, particularly those related to oxidative stress. Molecular docking results demonstrated that GA could bind effectively to the six key targets via hydrogen bonding and hydrophobic interactions. Furthermore, molecular dynamics simulations confirmed the binding stability of GA with MAOA, PTGS2, and BCL2. This study systematically elucidates the evolution of GA in aged white tea and its potential anti-aging mechanisms, providing a theoretical basis for the development of GA and aged white tea as functional anti-aging additives.