Longevity Papers

The immune system comprises multiple cell lineages and subsets maintained in tissues throughout the lifespan, with unknown effects of tissue and age on immune cell function. Here we comprehensively profiled RNA and surface protein expression of over 1.25 million immune cells from blood and lymphoid and mucosal tissues from 24 organ donors aged 20-75 years. We annotated major lineages (T cells, B cells, innate lymphoid cells and myeloid cells) and corresponding subsets using a multimodal classifier and probabilistic modeling for comparison across tissue sites and age. We identified dominant site-specific effects on immune cell composition and function across lineages; age-associated effects were manifested by site and lineage for macrophages in mucosal sites, B cells in lymphoid organs, and circulating T cells and natural killer cells across blood and tissues. Our results reveal tissue-specific signatures of immune homeostasis throughout the body, from which to define immune pathologies across the human lifespan.

Aging is a series of adverse changes over time that increases mortality risk. Several hypotheses have been proposed to explain aging, including Leslie Orgel's Error-Catastrophe Theory, which asserts that translation errors erode the translational machinery, become self-amplifying, and eventually lead to death. Evidence for the theory is scarce, especially regarding intra-specific fidelity-longevity correlations. Here, we demonstrate that the correlation can be hidden by the constrained evolution of translational fidelity, but remains detectable in long-lived samples. Measuring the lifespan and translational fidelity of a panel of BY × RM yeast recombinant haploid progenies, we validate the fidelity-longevity correlation. QTL analyses reveal that both fidelity and longevity are most strongly associated with a locus encoding vacuolar protein sorting-associated protein 70(VPS70). Replacing VPS70 in BY by its RM allele reduces translation error by ~8.0% and extends lifespan by ~8.9% through a vacuole-dependent mechanism. Our results support the impact of translational fidelity on intra-specific longevity variation.

Aging involves processes spanning orders of magnitude in time, from fast events that occur at the molecular scale to the slow decrease of physiological function. Whether and how fast molecular events lead to the slow progression of aging, and what ultimately sets the timescale of aging, is not understood. Here, by focusing on dynamic changes in DNA methylation, we show how aging phenomena on long timescales emerge from the kinetics of fast molecular processes, providing a bridge between temporal scales. By combining DNA methylation sequencing data across a range of timescales with a statistical modeling-based approach, we show that DNA methylation aging is governed by a three-fold hierarchy of processes that dominate on distinct timescales: individual stochastic events in which enzymes interact with the DNA and with each other (milliseconds); the convergence of molecular concentrations to steady states (days to months); and stochastic transitions between these steady states (years to decades). Our findings provide a unified picture of how DNA methylation aging arises across temporal scales.

The focal adhesion (FA) is the structural basis of the cell-extracellular matrix crosstalk and plays important roles in control of organ formation and function. Here we show that expression of FA protein vinculin is dramatically reduced in osteocytes in patients with aging-related osteoporosis. Vinculin loss severely impaired osteocyte adhesion and dendrite formation. Deleting vinculin using the mouse 10-kb Dmp1-Cre transgenic mice causes dramatic bone loss in the weight-bearing long bones and spine, but not in the skull, in both young and aged mice by impairing osteoblast formation and function without markedly affecting bone resorption. Vinculin loss impairs the anabolic response of skeleton to mechanical loading in mice. Vinculin knockdown increases, while vinculin overexpression decreases, sclerostin expression in osteocytes without impacting expression of Mef2c, a major transcriptional regulator of the Sost gene, which encodes sclerostin. Vinculin interacts with Mef2c and retains the latter in the cytoplasm. Thus, vinculin loss enhances Mef2c nuclear translocation and binding to the Sost enhancer ECR5 to promote sclerostin expression in osteocytes and reduces bone formation. Consistent with this notion, deleting Sost expression in osteocytes reverses the osteopenic phenotypes caused by vinculin loss in mice. Finally, we find that estrogen is a novel regulator of vinculin expression in osteocytes and that vinculin-deficient mice are resistant to ovariectomy-induced bone loss. Thus, we demonstrate a novel mechanism through which vinculin inhibits the Mef2c-driven sclerostin expression in osteocytes to promote bone formation.

Cytoskeleton-Associated Protein 4 (CKAP4) is a multifunctional protein implicated in diverse cellular processes, including cytoskeletal organization, signal transduction, and extracellular matrix remodeling. Recent studies have highlighted the dual role of CKAP4 in regulating cell growth and aging. On one hand, CKAP4 can promote cell proliferation and survival by activating signaling pathways such as PI3K/Akt, thereby delaying cellular senescence under physiological conditions. On the other hand, under chronic stress or pathological stimuli, CKAP4 may induce cell cycle arrest and accelerate aging by interacting with ligands such as antiproliferative factor (APF) and Dickkopf-1 (DKK1), leading to the upregulation of cell cycle inhibitors and the suppression of autophagy. Moreover, CKAP4 has emerged as a key mediator linking extracellular matrix remodeling to inflammatory responses, which are closely associated with age-related diseases. This review comprehensively summarizes the current understanding of CKAP4's molecular mechanisms in cell longevity and aging, discusses its involvement in inflammation and tissue homeostasis, and explores its potential as a therapeutic target for aging-related disorders.

Aging is a major risk factor in amyotrophic lateral sclerosis (ALS) and other adult-onset neurodegenerative disorders. Whereas young neurons are capable of buffering disease-causing stresses, mature neurons lose this ability and degenerate over time. We hypothesized that the resilience of young motor neurons could be restored by reexpression of the embryonic motor neuron selector transcription factors ISL1 and LHX3. We found that viral reexpression of ISL1 and LHX3 selectively in postnatal motor neurons reactivates aspects of their youthful gene expression program and alleviates key disease-relevant phenotypes in the SOD1

Aging is increasingly recognized as a systemic process, yet the mechanisms by which senescent cells signal from peripheral tissues accelerate brain aging remain poorly defined. Here, we used chronic exposure of human cerebral organoids to the secretome of senescent osteocytes to investigate how peripheral aging signals reshape brain tissue architecture. We combined spatially resolved optical fiber-based interferometry nanoindentation with transcriptomic and immunofluorescence profiling, demonstrating that bone-derived senescence-associated secretory phenotype (SASP) factors induce a biphasic mechanical response, early global tissue softening, followed by the emergence of discrete hyper-stiff microdomains. This spatially heterogeneous biomechanical remodeling was accompanied by upregulation of extracellular matrix (ECM), inflammatory, and senescence pathways, and suppression of neurodevelopmental and synaptic gene networks. Our results reveal that chronic paracrine SASP exposure from senescent osteocytes drives localized ECM reorganization and mechanical vulnerability in human brain tissue, providing mechanistic insight into how peripheral cellular senescence may contribute to regional brain fragility during aging.

Resting and maximal exercise respiratory rates (V̇O

Mass spectrometry (MS)-based metabolomics is a key technology for the interrogation of exogenous and endogenous small molecule mediators that influence human health and disease. To date, however, low throughput of MS systems have largely precluded large-scale metabolomics studies of human populations, limiting power to discover physiological roles of metabolites. Here, we introduce a fully automated rapid liquid chromatography-mass spectrometry (rLC-MS) system coupled to an AI-enabled computational pipeline that enables high-throughput, reproducible, non-targeted metabolite measurements across tens of thousands of samples. This system captures thousands of polar, amphipathic and nonpolar (lipid) metabolites in a human plasma sample in 53 seconds of analytical time, enabling analysis of greater than 1,000 samples per day per instrument. To demonstrate the discovery power of the rLC-MS platform, a subset of samples from Sapient\'s DynamiQ biorepository -- comprised of 62,039 total plasma samples collected longitudinally from 11,045 individuals -- were selected for deep analysis by rLC-MS to capture a rich, dynamic landscape of chemical variation that reflects both physiological processes and environmental influences. 26,042 plasma samples with matched real-world data (RWD) were chosen for the study, representing 6,935 individuals with diverse demographic backgrounds and disease profiles. Unbiased exploratory analysis revealed human metabotypes that correlate with heterogenous disease phenotypes, including key sub-populations of cardiometabolic and other human diseases. Moreover, a metabolic aging clock machine learning model trained on healthy individuals in this dataset accurately predicted accelerated aging in various chronic diseases, with dynamic reversal of metabolic aging following definitive therapy. These data demonstrate that the rLC-MS platform enables prediction of clinically relevant physiological states from plasma metabolomics at scale in human populations.

Aging significantly influences host immune responses to viral infections, including Severe Fever with Thrombocytopenia Syndrome Virus (SFTSV), which is associated with high mortality in elderly patients. Despite its high fatality rate and pandemic potential, effective therapies remain unavailable, and the age-dependent mechanisms underlying SFTSV pathogenesis are not fully understood. To address this gap, we employed a ferret model (an immunocompetent animal model that mimics human SFTSV infections) and performed multi-tissue single-cell RNA sequencing and histopathological analyses. Our results reveal that, upon SFTSV infection, aged ferrets experience extensive decrease of critical immune cells (particularly B and T cells) due to infection-induced cell death and excessive hemophagocytosis in hematopoietic organs, whereas young-adult ferrets rapidly clear the virus with minimal lymphocyte changes. Notably, aged ferrets display marked immune dysregulation, characterized by non-specific activation of T-bet ⁺ age-associated memory B cells (T-bet+ ABCs) and the proliferation of defective plasmablasts (MKI67 ⁺ PB1), which serve as major viral reservoirs and drive systemic viral dissemination. Comparative analysis further demonstrated that the MKI67 ⁺ PB1 subset dominates SFTSV⁺ cells in both aged ferrets and human fatal cases, exhibiting the highest per-cell viral UMI counts. Moreover, monocytes and macrophages in aged ferrets exhibit heightened inflammatory gene expression, contributing to the hyper-inflammatory state observed during infection. Collectively, these insights underscore the critical role of dysregulated memory B cell responses and hyper-inflammation in age-dependent SFTSV pathogenesis, highlighting potential targets for interventions in elderly populations.

Aging causes significant changes in gene expression and metabolic function of cells in various organs. Although it is known that liver regeneration is delayed by aging, the effects of aging on changes in gene expression and metabolic functions in liver regeneration need further investigation. In this study, we comprehensively analyzed changes in gene expression and metabolic function by liver regeneration in young and old mice to examine the effects of aging on these changes. During the process of liver regeneration, the gene expression profiles of hepatocytes from young and old mice changed significantly in a stepwise manner while each remained close together. After the completion of liver regeneration, the genes with aging-specific expression patterns in old mouse hepatocytes changed to expression levels close to those in young mouse hepatocytes. In contrast to the results of these transcriptome analyses, the aging-specific changes in metabolic state detected in old mouse livers were found to be largely maintained after the completion of liver regeneration. These results demonstrated that the gene expression state in the liver of old mice is flexibly altered by liver regeneration, whereas their metabolic state is robust. This finding helps to elucidate the relationship between aging and liver regeneration and to determine the basis of the increased incidence of liver disease with aging.

Aging is increasingly understood as a multifactorial process involving mitochondrial dysfunction, epigenetic drift, and chronic inflammation. While many age-related pathologies have been linked to impaired mitophagy and transcriptional deregulation, the upstream mechanisms driving these phenomena remain elusive. Here, a unifying hypothesis is proposed: that the progressive reactivation of human endogenous retroviruses (HERVs), combined with latent viral infections acquired during life, imposes an escalating burden on the epigenetic regulatory system. This "virome pressure" demands continuous silencing via DNA methylation, histone deacetylation, and NAD⁺-dependent pathways. With age, these silencing mechanisms deteriorate, leading to HERV reactivation, disruption of key mitochondrial quality control genes, and activation of innate immune responses. This is likened to a molecular peat bog, a simmering threat buried beneath the surface, where silencing mechanisms struggle to contain viral elements until pressure builds and erupts as the organism ages. This model integrates virology, epigenetics, and mitochondrial biology to offer novel insights into the aging process and suggests new targets for therapeutic intervention research.

Skeletal muscle stem cells (MuSCs) have strong regenerative abilities, but as we age, their ability to regenerate decreases, leading to a decline in muscle function. Although the methylation reprogramming of super-enhancers (SEs) plays a pivotal role in regulating gene expression associated with the aging process, our understanding of the molecular diversity of stem cells during aging remains limited. This study aimed to identify the methylation profile of SEs in MuSCs and explore potential therapeutic molecular targets associated with aging.

Persistent genomic instability compromises cellular viability while also triggers non-cell-autonomous responses that drive dysfunction across tissues, contributing to aging. Recent evidence suggests that DNA damage activates secretory programs, including the release of inflammatory cytokines, damage-associated molecular patterns, and extracellular vesicles, that reshape immune homeostasis, stem cell function, and metabolic balance. Although these responses may initially support tissue integrity and organismal survival, their chronic activation has been associated with tissue degenerative changes and systemic decline. Here, we discuss how nuclear DNA damage responses trigger the activation of cytoplasmic sensing pathways, promote secretory phenotypes, and affect organismal physiology. Targeting DNA damage-driven mechanisms may help buffer harmful systemic responses while preserving regeneration and immune surveillance, offering new ways to delay aging-related decline.

Aging is associated with a chronic, low-grade inflammatory state referred to as inflammaging, which contributes to impaired immune regulation and increased susceptibility to disease. While regulatory T (Treg) cells are key mediators of immune homeostasis, their role in the context of age-related inflammation remains poorly understood. Here we demonstrate that age-related changes in the microbiota promote impaired Treg cell function, resulting in the differentiation of inflammatory T cells. In agreement, we find that aged germ-free (GF) mice exhibited a more balanced immune profile, where the Treg cells are functional and pro-inflammatory mediators are reduced, suggesting that microbial exposure is essential for the establishment of inflammaging. Furthermore, we show that the use of old microbiota in young animals was sufficient to induce pro-inflammatory T cell responses and impaired mucosal Treg cell proliferation, while young microbiota restored Treg cell function in old animals. Mechanistically, we show that exposure to aged microbiota was associated with sustained TNF signaling, elevated oxidative stress, DNA damage, and increased expression of senescence markers such as {gamma}H2AX and p16 in Treg cells. These findings uncover a microbiota-TNF- dependent mechanism by which age-associated microbial dysbiosis drives Treg cell dysfunction and promotes immune aging, highlighting the therapeutic potential of microbiota-targeted strategies to restore immune homeostasis in the elderly.

Evidence connecting skin aging to functional decline and systemic aging biomarkers is lacking. This study investigated how skin-aging biomechanics were associated with changes in intrinsic capacity (IC), a marker of healthy aging. We also explored their links with biological aging clocks (epigenetic and inflammatory clocks) and potential moderating effects on the skin-IC relationship. Baseline skin elasticity and viscoelasticity were measured in 441 INSPIRE-T participants aged 20 to 93 (59.9% women) using Cutometer parameters. IC was evaluated over 3 years as a five-domain score covering cognition, locomotion, psychology, vitality, and sensory (a higher score indicated better). Biological aging was measured at baseline using six epigenetic clocks (Horvath pan-tissue, Horvath skin & blood, Hannum, PhenoAge, GrimAge, and DunedinPACE) and inflammatory clock (iAge). Poor skin elasticity and viscoelasticity in older adults were associated with lower baseline IC after controlling for demographic, medical, and lifestyle factors. Longitudinally, older men with a higher viscoelastic ratio (R6) experienced a faster decline in IC (a standardized coefficient [95% CI] ranged from -0.37 [-0.72, -0.03] at age 62 to -1.32 [-1.91, -0.73] at age 93). Accelerated iAge was associated with reduced skin elasticity (R2, R5, R7). Moreover, the association between parameters related to elastic recovery (R5, R7) and baseline IC became more pronounced as accelerated iAge increased. This is the first study demonstrating the association between skin-aging biomechanics and IC. Poor skin elasticity was associated with higher systemic inflammation. Therefore, skin biomechanical properties may reflect overall functional aging, with inflammation serving as a common underlying factor.

The transcriptional complex Mondo/Max-like, MML-1/MXL-2, acts as a convergent transcriptional regulatory output of multiple longevity pathways in

Optimal sleep plays a vital role in promoting healthy aging and enhancing longevity. This study proposes a Sleep Chart to assess the relationship between sleep duration and 23 biological aging clocks across 17 organ systems or tissues and 3 omics data types (imaging, proteomics, and metabolomics). First, a systemic, U-shaped pattern shows that both short (<6 hours) and long (>8 hours) sleep duration are linked to elevated biological age gaps (BAGs) across 9 brain and body systems and 3 omics types, with optimal sleep time varying by organ and sex ([6.4-7.8] hours). Furthermore, short and long sleep duration, compared to a normal sleep duration ([6-8] hours), are consistently linked to increased risk of systemic diseases beyond the brain and all-cause mortality, with evidence from genetic correlations and time to incident disease predictions, such as migraine, depression, and diabetes. Finally, short and long sleep duration are associated with late-life depression via distinct pathways: long sleep may contribute indirectly through biological aging processes, while short sleep shows a more direct link. Although our Mendelian randomization does not show strong causal effects from disease to sleep disturbances, it does not fully rule out the possibility that sleep disturbances may, in part, reflect underlying disease burden. Our findings suggest that the U-shaped relationship is likely driven by modifiable sleep disturbances rather than genetic predisposition, highlighting the potential of sleep optimization to support healthy aging, lower disease risk, and extend longevity. An interactive web portal is available to explore the Sleep Chart at: https://labs-laboratory.com/sleepchart.