Longevity Papers

Large-scale brain networks are vulnerable to change with aging and become dysregulated. How these networks are altered at the cellular level remains unclear owing to challenges of bridging data across scales. Here, we integrate in vivo cortical similarity networks with whole brain spatial transcriptomics to characterize the aging brain in a lifespan cohort of macaques (N=64, ages 1-26 years). Deep-layer excitatory neurons and oligodendrocytes emerged as dominant correlates of cortical similarity, linking infragranular cell type composition to macroscopic network structure. Age-related declines in network strength were most pronounced in transmodal networks, including default mode and limbic, and aligned with regions enriched in inhibitory and glial cell types. Parvalbumin-enriched chandelier cells showed the strongest association with regional vulnerability, suggesting a role in network disconnection. Cell-type enrichment was conserved across species, with both human and macaque transcriptomic data aligning with the cortical functional hierarchy. These findings uncover a cellular basis for cortical network aging and highlight the value of imaging-transcriptomic integration across scales.

Vascular smooth muscle cell (VSMC) senescence is a pivotal driver of atherosclerosis (AS), but molecular links to ageing-related dysfunction are unclear. It is aimed to identify regulators of VSMC senescence and develop clinical interventions for ageing-related AS. Using single-cell RNA sequencing of human atherosclerotic carotid arteries and immunofluorescence validation, activating transcription factor 3 (ATF3) is identified as central to VSMC senescence. Mechanistic studies employ SMC-specific ATF3 knockout mice, CUT&Tag-seq, RNA/protein interaction assays, and m6A epitranscriptomic analyses. To bridge discovery to therapy, high-throughput virtual screening is performed for ATF3-targeting compounds and functionally validated hits. ATF3 deficiency in VSMCs accelerates ageing-induced AS by promoting senescence. Multi-omics showed ATF3 activates ATG7, triggering autophagy, while cytoplasmic ATG7 enhances ATF3 nuclear translocation, establishing a positive feedback loop. Ageing increases m6A methylation and decreases the stability of Atf3 mRNA. Terazosin (TZ) diminishes the interaction between YTH N6-methyladenosine RNA binding protein F2 (YTHDF2) and Atf3 mRNA, helping to preserve Atf3 mRNA stability. TZ is a promising therapeutic strategy for delaying VSMC senescence and preventing AS. ATF3 protects against VSMC senescence and AS by orchestrating autophagy via a novel ATF3-ATG7 amplification loop. Repurposing TZ to stabilize ATF3 offers a translatable approach to combat ageing-driven cardiovascular disease.

Accumulation of cytosolic DNA has emerged as a hallmark of aging, inducing sterile inflammation. Stimulator of interferon genes (STING) protein translates the sensing of cytosolic DNA by cyclic-GMP-AMP synthase (cGAS) into an inflammatory response. However, the molecular mechanisms whereby cytosolic DNA-induced cGAS-STING pathway leads to aging remain poorly understood. We show that STING does not follow the canonical pathway of activation in human fibroblasts passaged (aging) in culture, senescent fibroblasts, or progeria fibroblasts (from Hutchinson-Gilford progeria syndrome patients). Despite cytosolic DNA buildup, features of the canonical cGAS-STING pathway like increased cGAMP production, STING phosphorylation, and STING trafficking to perinuclear compartment are not observed in progeria/senescent/aging fibroblasts. Instead, STING localizes at endoplasmic reticulum, nuclear envelope, and chromatin. Despite the nonconventional STING behavior, aging/senescent/progeria cells activate inflammatory programs such as the senescence-associated secretory phenotype and the interferon response, in a cGAS and STING-dependent manner, revealing a noncanonical pathway in aging. Importantly, progeria/aging/senescent cells are hindered in their ability to activate the canonical cGAS-STING pathway with synthetic DNA, compared to young cells. This deficiency is rescued by activating vitamin D receptor signaling, unveiling mechanisms regulating the cGAS-STING pathway in aging. Significantly, in HGPS, inhibition of the noncanonical cGAS-STING pathway ameliorates cellular hallmarks of aging, reduces tissue degeneration, and extends the lifespan of progeria mice. Our study reveals that a new feature of aging is the progressively reduced ability to activate the canonical cGAS-STING pathway in response to cytosolic DNA, triggering instead a noncanonical pathway that drives senescence/aging phenotypes.

Plasma proteins derived from specific organs can estimate organ age and mortality, but their sensitivity to environmental factors and their robustness in forecasting onset of organ diseases and mortality remain unclear. To address this gap, we estimate the biological age of 11 organs using plasma proteomics data (2,916 proteins) from 44,498 individuals in the UK Biobank. Organ age estimates were sensitive to lifestyle factors and medications and were associated with future onset (within 17 years' follow-up) of a range of diseases, including heart failure, chronic obstructive pulmonary disease, type 2 diabetes and Alzheimer's disease. Notably, having an especially aged brain posed a risk of Alzheimer's disease (hazard ratio (HR) = 3.1) that was similar to carrying one copy of APOE4, the strongest genetic risk factor for sporadic Alzheimer's disease, whereas a youthful brain (HR = 0.26) provided protection that was similar to carrying two copies of APOE2, independent of APOE genotype. Accrual of aged organs progressively increased mortality risk (2-4 aged organs, HR = 2.3; 5-7 aged organs, HR = 4.5; 8+ aged organs, HR = 8.3), whereas youthful brains and immune systems were uniquely associated with longevity (youthful brain, HR = 0.60 for mortality risk; youthful immune system, HR = 0.58; youthful both, HR = 0.44). Altogether, these findings support the use of plasma proteins for monitoring of organ health and point to the brain and immune systems as key targets for longevity interventions.