Longevity Papers

Clonal hematopoiesis (CH) is characterized by expanding blood cell clones carrying somatic mutations in healthy aged individuals and is associated with various age-related diseases and all-cause mortality. While CH mutations affect diverse genes associated with myeloid malignancies, their mechanisms of expansion and disease associations remain poorly understood. We investigate the relationship between clonal fitness and clinical outcomes by integrating data from three longitudinal aging cohorts (n=713, observations=2,341). We demonstrate pathway-specific fitness advantage and clonal composition influence clonal dynamics. Further, the timing of mutation acquisition is necessary to determine the extent of clonal expansion reached during the host individual\'s lifetime. We introduce MACS120, a metric combining mutation context, timing, and variant fitness to predict future clonal growth, outperforming traditional variant allele frequency measurements in predicting clinical outcomes. Our unified analytical framework enables standardized clonal dynamics inference across cohorts, advancing our ability to predict and potentially intervene in CH-related pathologies.

Aging is the primary risk factor for most neurodegenerative diseases, yet the cell-type-specific progression of brain aging remains poorly understood. Here, we developed human cell-type-specific transcriptomic aging clocks using high-quality single-nucleus RNA sequencing data from post mortem human prefrontal cortex tissue of 31 donors aged 18-94 years, encompassing 73,941 high-quality nuclei. We observed distinct transcriptomic changes across major cell types, including upregulation of inflammatory response genes in microglia from older samples. Aging clocks trained on each major cell type accurately predicted chronological age and remained robust in independent single-nucleus RNA-sequencing datasets, underscoring their broad applicability. These findings demonstrate the feasibility of cell-type-specific transcriptomic clocks to measure biological aging in the human brain and highlight potential mechanisms of selective vulnerability in neurodegenerative diseases. We anticipate these clocks will serve as a basis for further studies in other brain regions and more diverse populations, ultimately advancing our understanding of age-related neurodegenerative processes at the single-cell level.

Female reproductive aging is accompanied by a dramatic rise in the incidence of egg aneuploidy. Premature loss of chromosome cohesion proteins and untimely separation of chromosomes is thought to underly high rates egg aneuploidy during maternal aging. However, because chromosome cohesion loss occurs gradually over female reproductive lifespan and cytoskeletal defects alone can predispose eggs to chromosomal abnormalities, the root causes of exponential rise in egg aneuploidy at advanced reproductive ages remain a mystery. Here, we applied high-resolution live imaging to visualize for the first time cohesion protein dynamics underpinning meiotic chromosome segregation. To discover proteins whose dysfunction accelerates aneuploidies associated with female reproductive aging, we innovated the first experimental system in which chemically induced cohesion reduction rapidly triggers aging-like chromosomal abnormalities in young eggs. By integrating this direct cohesion manipulation system with quantitative high-resolution microscopy and targeted protein degradation tools, we identified the centromeric protein CENP-A as a new factor whose aging-like depletion causes a dramatic rise in premature separation of sister chromatids. Our work illuminates cohesion loss-independent origins of age-related egg aneuploidy and provides new avenues to discover therapeutic targets for extending the female reproductive lifespan.

Aging and metabolic disorders share intricate molecular pathways, with the Forkhead box O (FOXO)- Sirtuin 1 (SIRT1) axis emerging as a pivotal regulator of cellular stress adaptation, metabolic homeostasis, and longevity. This axis integrates nutrient signaling with oxidative stress defence, modulating glucose and lipid metabolism, mitochondrial function, and autophagy to maintain cellular stability. FOXO transcription factors, regulated by SIRT1 deacetylation, enhance antioxidant defence mechanisms, activating genes such as superoxide dismutase (SOD) and catalase, thereby counteracting oxidative stress and metabolic dysregulation. Recent evidence highlights the dynamic role of reactive oxygen species (ROS) as secondary messengers in redox signaling, influencing FOXO-SIRT1 activity in metabolic adaptation. Additionally, key redox-sensitive regulators such as nuclear factor erythroid 2-related factor 2 (Nrf2) and Peroxisome proliferator-activated receptor gamma coactivator-1 alpha (PGC-1α) interact with this pathway, orchestrating mitochondrial biogenesis and adaptive stress responses. Pharmacological interventions, including alpha-lipoic acid (ALA), resveratrol, curcumin and NAD

Cardiovascular diseases (CVDs) are experiencing a rapid surge and are widely recognized as the leading cause of mortality in the current aging society. Given the multifactorial etiology of CVDs, understanding the intricate molecular and cellular mechanisms is imperative. Over the past 2 decades, many scientists have focused on Sirtuins, a family of nicotinamide adenine dinucleotide-dependent deacylases. Sirtuins are highly conserved across species, from yeasts to primates, and play a crucial role in linking aging and diseases. Sirtuins participate in nearly all key physiological and pathological processes, ranging from embryogenic development to stress response and aging. Abnormal expression and activity of Sirtuins exist in many aging-related diseases, while their activation has shown efficacy in mitigating these diseases (eg, CVDs). In terms of research, this field has maintained fast, sustained growth in recent years, from fundamental studies to clinical trials. In this review, we present a comprehensive, up-to-date discussion on the biological functions of Sirtuins and their roles in regulating cardiovascular biology and CVDs. Furthermore, we highlight the latest advancements in utilizing Sirtuin-activating compounds and nicotinamide adenine dinucleotide boosters as potential pharmacological targets for preventing and treating CVDs. The key unresolved issues in the field-from the chemicobiological regulation of Sirtuins to Sirtuin-targeted CVD investigations-are also discussed. This timely review could be critical in understanding the updated knowledge of Sirtuin biology in CVDs and facilitating the clinical accessibility of Sirtuin-targeting interventions.

Synapse dysfunction is tightly linked to cognitive changes during aging, but underlying mechanisms driving dysfunction are minimally understood. The extracellular matrix (ECM) can potently regulate synapse integrity and plasticity. Yet the status of the brain ECM during aging remains virtually unexplored. Using novel ECM-optimized proteomic workflows, we discovered striking regional differences in ECM composition and aging-induced ECM remodeling. ECM status was also aligned with preserved synapse protein abundance across key basal ganglia nuclei. Moreover, using novel reward-learning paradigms and confocal imaging in fixed tissue, we demonstrated that reduced ECM-synapse remodeling and microglial aging phenotypes, are both linked with deficits in goal-directed behavior in aging mice. Finally, using mouse models of microglia ablation and premature microglial aging, we identified microglial aging phenotypes that promote ECM deposition and synapse numbers. Together, these foundational observations implicate glial-ECM interactions in the regulation of synapse function and cognitive abilities across the lifespan.

Telomeres shorten with each cell division, acting as a chronometer of cell age. The enzyme telomerase, primarily active in stem cells, reverses telomere erosion. We have previously observed that transient transfection with human TERT mRNA extends telomeres and mitigates hallmarks of senescence in replicatively aged human cells or those affected by Hutchinson-Gilford progeroid syndrome (HGPS). However, due to its short half-life, mRNA requires frequent administration. In this study, we hypothesized that TERT circular (circ) RNA would extend the duration of telomerase expression and be more effective at reversing hallmarks of senescence in endothelial cells derived from HGPS patients. We observe that a single transfection of TERT circRNA is more effective than mRNA in the extension of telomere length, as determined by quantitative fluorescence in situ hybridization. Furthermore, TERT circRNA reduced the number of β-gal positive cells by three-fold and normalized nuclear morphology in HGPS endothelial cells (HGPS-ECs). Moreover, TERT circRNA substantially reduced senescent markers, inflammatory markers, and DNA damage markers, including Progerin, p16, p21, IL-1B, IL-6, IL-8, MCP1, and γH2AX. Additionally, it restored NO production, enhanced cell proliferation, promoted angiogenesis, improved LDL uptake, reduced mitochondrial ROS, and normalized mitochondrial membrane potential more effectively. Our data suggest that TERT circRNA is superior to linear TERT mRNA in reversing processes involved in senescence.