Longevity Papers

Aging is characterized by a progressive decline in physiological function, driven by interconnected molecular hallmarks that increase the risk of chronic diseases. To extend health span, interventions targeting these hallmarks, including lifestyle modifications, pharmacological agents, and genetic strategies, have been developed. Among these, partial reprogramming, the transient expression of Yamanaka factors, has emerged as a powerful approach to reverse age-related cellular damage and restore youthful epigenetic and transcriptional signatures without erasing cell identity. This perspective highlights the therapeutic possibilities arising from the convergence of partial reprogramming with the innovative technology of ex vivo machine perfusion. These platforms offer a unique opportunity to apply rejuvenation therapies directly to suboptimal donor organs outside the body before transplantation. Combining these strategies could significantly improve organ quality, expand the donor pool, enhance transplantation outcomes, and advance regenerative medicine.

Exposure to a younger system can induce organismal rejuvenation, yet whether all tissues can be rejuvenated and by what mechanisms remains understudied. We performed heterochronic and isochronic transplantation of subcutaneous white adipose tissue (WAT) between young and old mice and longitudinally tracked changes in biological age. Transplantation accelerated tissue aging, and the molecular age of grafts shifted toward that of the host. Most importantly, old WAT was rejuvenated in a young body. Epigenetic and transcriptomic clocks revealed a reduction of predicted age, accompanied by coordinated activation of canonical and previously unrecognized thermogenic pathways. Molecular rejuvenation was further supported by architectural changes toward a youthful state, including reduced lipid droplet size and decreased cellular heterogeneity. Mitochondrial abundance and morphology remained unchanged, while collagen deposition increased. These results demonstrate that WAT biological age is partially reversible and identify molecular and cellular features underlying its rejuvenation.

Cellular rejuvenation through transcriptional reprogramming is an exciting approach to counter aging. Using a fibroblast-based model of human cell aging and Perturb-seq screening, we developed a systematic approach to identify single transcription factor (TF) perturbations that promote rejuvenation without dedifferentiation. Overexpressing E2F3 or EZH2, and repressing STAT3 or ZFX, reversed cellular hallmarks of aging-increasing proliferation, proteostasis, and mitochondrial activity, while decreasing senescence. EZH2 overexpression in vivo rejuvenated livers in aged mice, reversing aging-associated gene expression profiles, decreasing steatosis and fibrosis, and improving glucose tolerance. Mechanistically, single TF perturbations led to convergent downstream transcriptional programs conserved in different aging and rejuvenation models. These results suggest a shared set of molecular requirements for cellular and tissue rejuvenation across species.

O-GlcNAc modification is a key cellular signal, but its role in regulating senescence-associated transcription remains poorly understood. Here, we apply a time-resolved chemical genomics strategy to map dynamic O-GlcNAc chromatin-associated proteins (OCPs) during oncogene-induced senescence (OIS) in primary human fibroblasts. Chromatin O-GlcNAc modification continues to accumulate, while 1,987 senescence-associated OCPs undergo dynamic shifts in genomic occupancy across diverse epigenetic chromatin states and display bimodal regulatory activities within the 3,466-gene senescence transcriptome. O-GlcNAc facilitates the formation of dual-function complexes: TF-SWI/SNF activates senescence-associated secretory phenotype (SASP) genes at promoters, whereas NuRD enforces the repression of cell-cycle regulators at enhancers. Furthermore, we identify O-GlcNAc modified JUN and GATAD2A as key regulators of OIS phenotypes in both in vitro and in vivo models of senescence-driven tumorigenesis. These findings reveal dynamic regulation and chromatin organization principles of O-GlcNAc-related epigenetic factors, providing insights into cellular senescence and potential therapeutic strategies.

A fundamental question in biology is whether cellular aging is inevitable. Embryonic stem cells (ESCs) challenge this paradigm as rare normal cells capable of indefinite in vitro passage. However, the mechanisms underlying ESC lineage immortality remain unresolved. Using long-term live-cell imaging to follow fates of single ESCs, we show here that ESC lineage renewal is achieved through sporadic entry into a state characterized by the expression of two-cell embryo-specific markers. During this state, cells undergo asymmetric divisions, segregating accumulated DNA damage into one daughter lineage destined for elimination, while producing a second lineage that reverts to the pluripotent state. Importantly, the latter lineage exhibits signs of rejuvenation, including reduced DNA damage and enhanced chimeric efficiency. These findings underscore the crucial role of asymmetric cell division in maintaining the long-term health of the ESC lineage against mounting damage within individual cells, a potential model for studying cellular aging and rejuvenation in mammalian cells.

Cellular senescence of retinal pigment epithelium (RPE) cells drives age-related visual decline, particularly in the pathology of age-related macular degeneration (AMD). While genome-wide association studies (GWAS) have identified genetic risk factors underlying AMD, the molecular mechanisms governing RPE senescence remain unclear. Here, single-cell RNA sequencing of young and old mouse RPE revealed dysregulated cell-matrix adhesion as a key feature of senescence, consistent with transcriptional changes in AMD patients. Hydrogel-based experiments confirmed that impaired integrin-mediated adhesion induces RPE senescence. Yes-associated protein 1 (YAP), a crucial mechanotransducer, mediated the protective effects of cell-matrix adhesion, and its activation alone reversed aging phenotypes in senescent RPE cells. Notably, treatment with TRULI, a small-molecule YAP activator, significantly improved visual function in AMD and naturally aged mice. These findings highlight the integrin-YAP mechanotransduction pathway as a fundamental regulator of RPE senescence and a potential therapeutic target for AMD.

Cellular senescence has a dual role in both tumor suppression and the promotion of age-related diseases. This paradox suggests the existence of functionally distinct "beneficial" and "detrimental" senescent states, yet the molecular basis that governs their fate has remained elusive. Here, we reveal that the dynamic exchange of histone H2AX on chromatin functions as an essential quality control mechanism that dictates the quality of senescence. We demonstrate that the histone acetyltransferase TIP60, in complex with the chaperone FACT, acetylates H2AX at lysine 5 (K5), which in turn drives its dynamic exchange. This histone exchange is indispensable for promoting the degradation of the DNA damage response mediator MDC1, a process we uncover is mediated by a novel DNA-PKcs-p97 signaling axis. Disruption of this TIP60-FACT-H2AX exchange pathway leads to the hyperaccumulation of MDC1 and a shift toward error-prone nonhomologous end joining (NHEJ), inducing a pathological senescent state with oncogenic potential. Our study redefines histone exchange from a passive chromatin event to an active regulatory hub that determines the fate of aging cells. These findings provide a molecular basis for the heterogeneity of senescence and establish a rationale for developing "senomorphic" therapies aimed at improving the quality of aging.

Aging is intricately linked to neurodegenerative diseases and cognitive decline, with the prefrontal cortex (PFC) playing a critical role in higher cognitive functions such as decision-making and memory. Despite advances in transcriptomic profiling, our understanding of cell type-specific and spatial regulatory mechanisms in brain aging remains incomplete. This study integrates single-cell RNA sequencing (scRNA-seq), single-cell ATAC sequencing (scATAC-seq), and spatial transcriptomics to uncover molecular and cellular alterations associated with PFC aging. We analyzed data from 51 healthy human PFC samples, categorized into young, middle-aged, and elderly groups. Differential gene expression (DEG) analysis identified 3932 aging-related DEGs, among which excitatory neurons exhibited the most significant molecular alterations. This study suggests that EGR1 may serve as a potential key regulator of synaptic plasticity during aging; our findings indicate that reduced chromatin accessibility in the excitatory neurons of elderly individuals may subsequently lead to the downregulation of EGR1. Spatial transcriptomics revealed enriched EGR1 expression in specific cortical layers and its progressive decline with age. Furthermore, EGR1 targets-including YWHAZ, CTNNB1, and CDC42-were implicated in synaptic plasticity pathways such as the Wnt and Hippo signaling pathways. These findings suggest that EGR1 dysfunction may contribute to synaptic deficits and cognitive impairment during aging. This study provides a comprehensive view of cell-type-specific and spatial molecular mechanisms underlying PFC aging, highlighting EGR1 as a potential biomarker and therapeutic target for age-related cognitive decline. Our integrative approach advances the understanding of brain aging and lays the groundwork for anti-aging interventions.

Reprogramming of somatic cells into induced pluripotent stem cells through the introduction of transcription factors Oct3/4, Sox2, Klf4, and c-Myc (OSKM) represents a landmark advance in regenerative biology. Building on this foundation, partial reprogramming can help reset epigenetic age. It further opens opportunities to treat degenerative diseases without the tumorigenic risks associated with full pluripotency. The review advances the field in three ways: it links lineage-preserving partial reprogramming to quantifiable rejuvenation endpoints; defines mesenchymal drift as an age- and disease-associated trajectory amenable to reversal; and maps strategies beyond OSKM, including small-molecule programs and CRISPR-based control circuits. Convergent phenotypes are surveyed in nervous, metabolic, musculoskeletal, and craniofacial systems, with emphasis on improved tissue repair and regeneration. A translational checklist is proposed that emphasizes schedule, delivery, and safety pharmacology to guide rigorous preclinical studies and de-risk early clinical entry points for partial reprogramming therapies.

HIV persists in long-lived CD4 T cell reservoirs despite antiretroviral therapy (ART)1. Elite controllers suppress viraemia without ART2, yet reservoir reactivation emerges with immune ageing3. Here we show that transient reprogramming of patient-derived CD4 T cells restores their ability to eliminate HIV-infected reservoirs, excising integrated proviral DNA. A defined compound, or physiological induction, drove rapid reprogramming ex vivo, enabling clearance of HIV DNA within hours to days of treatment, independently of ART. Single-cell RNA sequencing revealed activation of an antiviral telomere transfer programme4 that exceeds elite-like control. In humanised mice, adoptive transfer of reprogrammed patient CD4 T cells, or in vivo reprogramming of murine T cells, eliminated HIV DNA across reservoirs, with undetectable viral genomes persisting for months. Modelling predicted that residual proviral reactivation would be governed by rare stochastic events, rendering viral rebound unlikely within a human lifespan. These findings identify a previously unrecognised form of intracellular immunity and establish a defined route to a functional HIV cure arising from the CD4 T cell itself.