Longevity Papers

Microglial senescence is a hallmark of brain aging, but how lysosomal dysfunction fuels their pro-aging activity remains unresolved. Here we identify cytosolic Cathepsin B (CatB) as a pivotal driver of microglial senescence. In aged mice and senescence-induced models, lysosomal membrane permeabilization releases CatB into the cytosol, where it remains enzymatically active at neutral pH. Cytosolic CatB promotes senescence, and its inhibition mitigates this process, whereas cytosolic delivery of recombinant CatB accelerates it. Mechanistically, cytosolic CatB binds and degrades small nuclear ribonucleoprotein polypeptide E (SNRPE), a spliceosome component, inducing senescence-associated phenotypes without triggering cell death. Notably, conventional CatB inhibitors active under acidic conditions are ineffective, while neutral pH-active inhibitors block microglial senescence both in vitro and in aged mouse brains. These findings uncover cytosolic CatB as a spliceosome-targeting mediator of microglial senescence and suggest SNRPE stabilization or compartment-specific CatB inhibition as potential therapeutic strategies to counter brain aging and neurodegeneration.

Traditional vascular aging research has predominantly focused on isolated pathologies in single vascular beds, which fails to explain the synchronized functional decline of multiple organ systems that defines organismal aging. While the panvascular aging paradigm has emerged as a transformative framework for understanding systemic aging, the field remains fragmented by inconsistent phenotypic definitions, arbitrary model selection, and a critical disconnect between basic mechanistic insights and clinical translation. Recent landmark investigations-including single-cell transcriptomic profiling of primate arterial aging, comprehensive multi-omics analyses of 30 tissues across the lifespan in non-human primates, and the development of the first human vascular organoid model of premature aging-have provided compelling molecular and temporal evidence supporting the pioneer organ hypothesis of aging. These studies suggest that the integrated circulatory network may represent an important regulatory hub influencing systemic aging trajectories, with the aortic arch exhibiting accelerated molecular alterations initiating as early as the third decade of life, preceding functional deterioration in all other visceral organs. Senescence propagates globally via vascular-specific secretory factors, extracellular vesicles (EVs), and impaired protein translation efficiency, driving synchronous dysfunction across the entire circulatory tree. This review addresses three critical unmet needs in the field. First, it establishes the first minimum diagnostic criteria for panvascular aging phenotypes, aligned with the latest VascAgeNet (Network for Research in Vascular Ageing) consensus, to prevent conceptual dilution and standardize cross-study comparisons. Second, it develops a problem-oriented model selection matrix that integrates cutting-edge three-dimensional human vascular organoids, multi-organ chip systems, and non-human primate models, providing actionable guidance for preclinical research design. Third, it systematically delineates the hierarchical mechanistic cascade by which panvascular aging drives multi-organ functional decline, identifies conserved core regulators of vascular senescence, and outlines a subtype-specific translational roadmap for vascular rejuvenation. By synthesizing fragmented knowledge into a cohesive, evidence-based framework, this work bridges the gap between basic research and clinical practice, and accelerates the implementation of the global VascAgeNet Roadmap.

Progressive mitochondrial dysfunction coupled with calcium dyshomeostasis is a hallmark of aging and neurodegenerative conditions, yet the molecular links to cognitive decline remain unclear. Moreover, although sex differences in susceptibility to neurodegeneration are well recognized, their molecular basis remains poorly defined. In our previously engineered mouse model, systemic depletion of Tusc2 (Fus1), a mitochondrial calcium-regulatory protein, accelerates aging and recapitulates key features of human aging, including sex-specific cognitive decline. Here, we identify Tusc2 as a key modulator of hippocampal (HP) resilience to aging. To define the impact of Tusc2 loss on molecular determinants of cognition, we profiled HP transcriptomes in both sexes and proteomes in males at 4 months of age, when sex-specific differences in cognitive behavior first emerge. Male knockout HP exhibited broad mitochondrial dysfunction, including suppression of oxidative phosphorylation (OxPhos) proteins, activation of the ATF4 branch of the integrated stress response (ISR), and coordinated downregulation of translational, proteasomal, and synaptic pathways. These molecular alterations were accompanied by increased protein aggregate size, consistent with impaired proteostatic capacity, and reduced PSD-95 neuropil intensity, indicative of compromised synaptic integrity in the HP. In contrast, female knockout HP exhibited comparatively modest transcriptional alterations and preferential activation of adaptive ATF6-associated unfolded protein response (UPR) pathways, consistent with a protective response that may be influenced by estrogen signaling, sex chromosome complement, epigenetic regulation, and other sex-dependent mechanisms. Comparative analysis with aging human HP datasets revealed significant and broad overlaps, suggesting that Tusc2 deficiency recapitulates key molecular features of human brain aging. Together, these findings identify TUSC2 as a principal regulator of mitochondrial calcium homeostasis that contributes to maintenance of proteostatic and synaptic integrity of the HP during aging, and reveal marked sex differences in mitochondrial stress resilience. These results establish Tusc2 deficiency as a mechanistically defined model for investigating early, potentially reversible stages of mitochondrial and proteostatic decline in brain aging.

Cellular senescence is a fundamental process that drives organismal aging and frailty through progressive oxidative stress, mitochondrial dysfunction, chronic inflammation, and impaired cellular quality-control systems. Accordingly, growing interest has focused on natural compounds capable of modulating the interconnected hallmarks of aging in a balanced and physiologically relevant manner. Schisandra chinensis (Turcz.) Baillon, a traditional medicinal fruit that is widely used in East Asian medicine, has recently emerged as a promising senostatic candidate. This review summarizes the current experimental evidence demonstrating that S. chinensis fruit (Schisandrae Fructus) extracts and their bioactive lignan constituents exert multilayered regulatory effects on cellular aging pathways. Accumulating evidence indicates that Schisandrae Fructus enhances redox homeostasis by suppressing excessive reactive oxygen species generation and activating endogenous antioxidant defense mechanisms. In parallel, Schisandrae Fructus constituents preserve mitochondrial function by maintaining the mitochondrial membrane potential, reducing mitochondrial oxidative stress, and promoting mitochondrial biogenesis. In addition to redox and mitochondrial regulation, Schisandrae Fructus suppresses senescence-associated secretory phenotype factors and inflammatory signaling cascades, thereby mitigating the chronic low-grade inflammation that reinforces senescence and tissue dysfunction. Emerging evidence further suggests that Schisandrae Fructus modulates autophagy- and mitophagy-related quality-control pathways, contributing to the removal of damaged cellular components and maintenance of cellular homeostasis. Importantly, the biological actions of Schisandrae Fructus favor adaptive and balanced regulation rather than excessive pathway activation, supporting its classification as a senostatic modulator rather than a cytotoxic agent. Overall, Schisandrae Fructus represents a compelling natural multitarget candidate for mitigating the core mechanisms of cellular aging and frailty. Further studies are needed to define its long-term efficacy and translational potential.

RNA splicing determines which protein isoforms a gene produces, and aberrant splice-site activation can cause severe disease. In Hutchinson-Gilford progeria syndrome, a synonymous LMNA mutation strengthens a cryptic 5' splice donor site to produce progerin, a toxic lamin A isoform driving premature cardiovascular death. Within this cryptic donor, the activating mutation lies near the canonical GT dinucleotide required for splice-site recognition. A single guide can therefore preferentially pair with the mutant sequence while positioning Cas9 cleavage at this dinucleotide. Here we show that CRISPR/Cas9-mediated disruption of this splice site suppresses progerin without requiring precise correction of the activating mutation and prolongs lifespan in progeroid mice. In patient-derived fibroblasts and induced pluripotent stem cell-derived mesenchymal stem cells, this intervention reduced progerin by 92.7-96.8% while retaining lamin A and lamin C expression. A single neonatal injection of AAV9 carrying the corresponding mouse guide increased median survival from 115 to 279 days in Cas9-expressing LmnaG609G/G609G mice. Treatment attenuated aortic, skeletal and multiorgan pathology. Treated homozygous pairs produced 52 offspring across seven litters. These findings establish pathogenic splice signals as genomic targets for sustained suppression of toxic isoforms while retaining canonical gene outputs.

Caloric restriction (CR) is among the most effective non-genetic strategies to extend lifespan and delay age-related metabolic decline. Yet, the molecular mediators linking CR to hepatic protection remain incompletely understood. Here, we performed age-stratified targeted oxylipin (lipid mediator) profiling of livers from ad libitum (AL) and CR mice across adulthood and aging. In AL-fed mice, ~9 months emerged as an inflection point where oxylipin networks shifted toward a pro-inflammatory state, marked by transient elevations in PGE₂, 11-keto-TXB₂, 20-HETE, and 5-oxo-ETE, with concomitant loss of pro-resolving/hydroxy-dihydroxylated mediators. Later life was characterized by depletion of CYP-derived epoxides and accumulation of soluble epoxide hydrolase (sEH)-generated diols, indicating impaired epoxide-to-diol coupling and resolution capacity. Lifelong CR dynamically reprogrammed these trajectories, blunting mid-life inflammatory surges, preserving EPA-derived epoxy-fatty acids (eg., EpETEs), and inducing the redox enzyme CYB5R3, which may sustain CYP epoxygenase activity (and epoxide output) despite reduced enzyme abundance. These oxylipin changes coincided with reduced hepatic lipid accumulation and a more favorable systemic metabolic profile in CR mice. Collectively, these findings identify age- and diet-associated remodeling of the hepatic COX/LOX/CYP oxylipin network, particularly the epoxide-diol profile, and nominate CYB5R3-associated redox regulation as a hypothesis for future mechanistic investigation.