DNA methylation clocks for estimating biological age in Chinese cohorts

Epigenetic clocks are accurate predictors of human chronological age based on the analysis of DNA methylation(DNAm)at specific CpG sites.However,a systematic comparison between DNA methylation data and other omics datasets has not yet been performed.Moreover,available DNAm age predictors are based on datasets with limited ethnic representation.To address these knowledge gaps,we generated and analyzed DNA methylation datasets from two independent Chinese cohorts,revealing age-related DNAm changes.Additionally,a DNA methylation aging clock(iCAS-DNAmAge)and a group of DNAm-based multi-modal clocks for Chinese individuals were developed,with most of them demonstrating strong predictive capabilities for chronological age.The clocks were further employed to predict factors influencing aging rates.The DNAm aging clock,derived from multi-modal aging features(compositeAge-DNAmAge),exhibited a close association with multi-omics changes,lifestyles,and disease status,underscoring its robust potential for precise biological age assessment.Our findings offer novel insights into the regulatory mechanism of age-related DNAm changes and extend the application of the DNAm clock for measuring biological age and aging pace,providing the basis for evaluating aging intervention strategies.

Aging hallmarks of the primate ovary revealed by spatiotemporal transcriptomics

The ovary is indispensable for female reproduction,and its age-dependent functional decline is the primary cause of infertility.However,the molecular basis of ovarian aging in higher vertebrates remains poorly understood.Herein,we apply spatiotemporal transcriptomics to benchmark architecture organization as well as cellular and molecular determinants in young primate ovaries and compare these to aged primate ovaries.From a global view,somatic cells within the non-follicle region undergo more pronounced transcriptional fluctuation relative to those in the follicle region,likely constituting a hostile microenvironment that facilitates ovarian aging.Further,we uncovered that inflammation,the senescent-associated secretory phenotype,senescence,and fibrosis are the likely primary contributors to ovarian aging(PCOA).Of note,we identified spatial co-localization between a PCOA-featured spot and an unappreciated MT2(Metallothionein 2)highly expressing spot(MT2^(high))characterized by high levels of inflammation,potentially serving as an aging hotspot in the primate ovary.Moreover,with advanced age,a subpopulation of MT2^(high)accumulates,likely disseminating and amplifying the senescent signal outward.Our study establishes the first primate spatiotemporal transcriptomic atlas,advancing our understanding of mechanistic determinants underpinning primate ovarian aging and unraveling potential biomarkers and therapeutic targets for aging and age-associated human ovarian disorders.

Single-nucleus profiling unveils a geroprotective role of the Foxo3 in primate skeletal muscle aging

Age-dependent loss of skeletal muscle mass and function is a feature of sarcopenia,and increases the risk of many aging-related metabolic diseases.Here,we report phenotypic and single-nucleus transcriptomic analyses of non-human primate skeletal muscle aging.A higher transcriptional fluctuation was observed in myonuclei relative to other interstitial cell types,indicating a higher susceptibility of skeletal muscle fiber to aging.We found a downregulation of Foxo3 in aged primate skeletal muscle,and identi-fied FOxo3 as a hub transcription factor maintaining skeletal muscle homeostasis.Through the establishment of a complementary experimental pipeline based on a human pluripotent stem cell-derived myotube model,we revealed that silence of Foxo3 accelerates human myotube senescence,whereas genetic activation of endogenous FOxO3 alleviates human myotube aging.Altogether,based on a combination of monkey skeletal muscle and human myotube aging research models,we unraveled the pivotal role of the FOxO3 in safeguarding primate skeletal muscle from aging,providing a comprehensive resource for the development of clinical diagnosis and targeted therapeutic interventions against human skeletal muscle aging and the onset of sarcopenia along with aging-relateddisorders.

A single-nucleus transcriptomic atlas of primate testicular aging reveals exhaustion of the spermatogonial stem cell reservoir and loss of Sertoli cell homeostasis

The testis is pivotal for male reproduction,and its progressive functional decline in aging is associated with infertility.However,the regulatory mechanism underlying primate testicular aging remains largely elusive.Here,we resolve the aging-related cellular and molecular alterations of primate testicular aging by establishing a single-nucleus transcriptomic atlas.Gene-expression patterns along the spermatogenesis trajectory revealed molecular programs associated with attrition of spermatogonial stem cell reservoir,disturbed meiosis and impaired spermiogenesis along the sequential continuum.Remarkably,Sertoli cell was identified as the cell type most susceptible to aging,given its deeply perturbed age-associated transcriptional profiles.Concomitantly,downregulation of the transcription factor Wilms'Tumor 1(WTi),essential for Sertoli cell homeostasis,was associated with accelerated cellular senescence,disrupted tight junctions,and a compromised cell identity signature,which altogether may help create a hostile microenvironment for spermatogenesis.Collectively,our study depicts in-depth transcriptomic traits of non-human primate(NHP)testicular aging at single-cell resolution,providing potential diagnostic biomarkers and targets for therapeutic interventions against testicular aging and age-related male reproductive diseases.