Longevity Papers

Yeast replicative aging is cell autonomous and thus a good model for mechanistic study from a dynamic systems perspective. Utilizing an engineered strain of yeast with a switchable genetic program to arrest daughter cells (without affecting mother cell divisions) and a high throughput microfluidic device, we systematically analyze the dynamic trajectories of thousands of single yeast mother cells throughout their lifespan, using fluorescent reporters that cover a range of biological processes, including some major aging hallmarks. We found that the markers of proteostasis stand out as most predictive of the lifespan of individual cells. In particular, nuclear proteasome concentration at middle age is a good predictor. We found that cell size (measured by area) grows linearly with time, and that nuclear size grows in proportion to maintain isometric scaling in young cells. As the cells become older, their nuclear size increases faster than linear and isometric size scaling breaks down. We observed that proteasome concentration in the nucleus exhibits dynamics very different from that in cytoplasm, with much more rapid decrease during aging; such dynamic behavior can be accounted for by the change of nuclear size in a simple mathematical model of transport. We hypothesize that the gradual increase of cell size and the associated nuclear size increase lead to the dilution of important nuclear factors (such as proteasome) that drives aging. We also show that perturbing proteasome changes mitochondria morphology and function, but not vice versa, potentially placing the change of proteosome upstream of the change of mitochondrial phenotypes. Our study produced large scale single cell dynamic data that can serve as a valuable resource for the aging research community to analyze the dynamics of other markers and potential causal relations between them. It is also a useful resource for building and testing physics/AI based models that identify early dynamics events predictive of lifespan and can be targets for longevity interventions.

Immunosenescence, the gradual deterioration of the immune system, is critical for aging-related diseases. However, the lack of detailed population-level immune data has limited our understanding, underscoring the need for innovative analytical approaches. The Health and Retirement Study (HRS) in the United States provides a unique opportunity to examine T and B lymphocyte subsets using compositional data analysis and dimension reduction techniques.

While developmental origins are suspected for many adult diseases, the lifespan effects of developmental perturbations have not been well studied. Cerebral Small Vessel Disease (SVD) is a leading cause of stroke and dementia and yet is often an incidental finding in aged patients due to the inaccessibility of brain vasculature to imaging of small vessels. In humans, reduced FOXF2 is associated with an increased stroke risk and SVD. We use a zebrafish partial foxf2 loss of function to model its effect on small vessel biology through development and aging. In the zebrafish, foxf2 is expressed in brain vascular pericytes and promotes vascular stability. We find that the initial pool of pericytes in developing foxf2a mutants is strongly reduced without affecting the endothelial network. The few brain pericytes present in mutants have strikingly longer processes and enlarged soma. foxf2a mutant pericytes can partially repopulate the brain after genetic ablation suggesting some recovery is possible. Nonetheless, adult foxf2a mutant brains show regional heterogeneity, with areas of normal pericyte coverage of vessels, but others with severe pericyte depletion. Both pericyte and endothelial morphology is strongly affected in adults. Taken together, foxf2a mutants fail to generate a sufficient initial population of pericytes and the few pericytes remaining have abnormal cell morphology. Over the lifespan foxf2a loss leads to severely abnormal cerebrovasculature. Our work opens new understanding of the progression of genetic forms of human Cerebral Small Vessel Disease.

Impaired activity of glutamate transporters, elevated concentration of extrasynaptic glutamate and hyperactivity of extrasynaptic GluN2B-containing NMDA receptors are common features in aging and several neurological conditions, including Alzheimer disease (AD). Previous studies revealed that polysialic acid (polySia), a glycan predominantly carried by the neural cell adhesion molecule NCAM, inhibits extrasynaptic NMDA receptors and supports synaptic plasticity in healthy adult brains. Moreover, intranasal delivery of polySia with the degree of polymerization 12 (NANA12) rescued synaptic plasticity and cognitive functions in models of tauopathy and amyloidosis associated with AD. Here, we comparatively studied the effects of NANA12 in young (4 months) old (26 months) and very old (29 months) mice. Strikingly, NANA12 promoted cognitive flexibility in attentional set-shifting (ASST) tests and spatial memory in the Barnes maze in very old mice. To capture fine-grained effects undetectable by conventional methods, we introduced a novel trial-wise data analysis approach for evaluating ASST performance. The observed cognitive improvements were not due to changes in the size of hippocampal memory engrams, visualized by c-Fos immunolabeling after reactivation of spatial memory in the probe trial. Five-day treatment with NANA12 did not affect neuronal structure (MAP2 levels), expression of senescence (lipofuscin) or neuroinflammation (microglial Iba1) markers, activation of BDNF receptors (p-TrkB) or expression of endogenous polySia in the hippocampus of very old mice. However, cognitive improvements correlated with the normalized size of CD68+ microglial lysosomes and reduced amounts of pre- and postsynaptic proteins at these structures. Thus, our data demonstrate the potential of short polySia to reduce synaptic phagocytosis and restore key cognitive functions attenuated in aging.

Patients with chronic obstructive pulmonary disease (COPD) often develop complications associated with sarcopenia; however, the underlying mechanisms remain unclear. Through a combination of in vitro and in vivo experiments, as well as bioinformatics analysis, our study identified YAP/TAZ as a key regulator of the aging phenotype in the skeletal muscle of COPD patients. In skeletal muscle affected by cigarette smoke-induced COPD, we observed significant reductions in YAP/TAZ levels, alongside markers indicative of skeletal muscle aging and dysfunction. Notably, overexpression of YAP/TAZ significantly improved these conditions. Our results suggest a novel mechanism whereby the maintenance of YAP/TAZ activity interacts with ACTR2 to preserve nuclear membrane integrity and reduce cytoplasmic dsDNA levels, thereby attenuating STING activation and cellular senescence. Additionally, we found that YAP is involved in the transcriptional regulation of the ACTR2 promoter region. Overall, preserving YAP/TAZ activity may help prevent skeletal muscle aging associated with COPD, representing a new strategy for intervening in COPD-related sarcopenia.

Telomere dysfunction is a key hallmark of aging linked to numerous age--related diseases including cardiovascular disorders, pulmonary fibrosis, and metabolic syndromes. Despite decades of research yielding strong evidence linking telomere biology to aging processes, the field faces a critical bottleneck: current telomere measurement methods require specialized molecular techniques that prevent large--scale studies and clinical implementation. Here we present TLPath, a novel deep learning framework that extracts normal tissue architecture from routine histopathology (H&E) images to predict bulk--tissue telomere length. Trained on the Genotype--Tissue Expression cohort comprising >7.3 million patch images from >5,000 whole--slide images across 919 individuals, TLPath makes a remarkable discovery: the extracted morphological features spontaneously separate young, middle--aged, and elderly individuals within most tissue types--demonstrating for the first time that aging causes substantial architectural changes in tissues detectable without explicit age supervision. These extracted features can predict bulk--telomere length with significant accuracy (>0.51 in well--represented tissues), outperforming chronological age as a predictor (correlation = 0.20) and identifying age--discordant cases -- detecting both accelerated telomeres shortening in young individuals and preserved telomeres in older individuals. Mechanistic interpretation reveals that TLPath leverages established senescence morphological markers, including nuclear--to--cytoplasmic ratio and nuclear shape variation, for its predictions. We applied TLPath in ~2,800 new GTEx biopsies where concordant with known association, the predicted telomere length is shorter across most tissues from individuals with Type 1/2 diabetes. Overall, we demonstrate that aging substantially alters tissue morphology, which TLPath captures and uses to predict telomere length, enabling large--scale telomere biology studies using existing tissue archives.

Age-related alterations in the skeletal system are linked to decreased bone mass, a reduction in bone strength and density, and an increased risk of fractures and osteoporosis. Therapeutics are desired to stimulate bone regeneration and restore imbalance in the bone remodeling process. Quercetin (Qu), a naturally occurring flavonoid, induces osteogenesis; however, its solubility, stability, and bioavailability limit its therapeutic use. Nanoformulation can improve the physical properties of Qu and enhance its bioactivity and bioavailability. Further, localized delivery of Qu nanoformulations at the site of bone defects could ensure high local concentration, augmenting its osteogenic properties. Thus, this study aims to synthesize selenium nanoparticles-based Qu nanoformulation (Qu-SeNPs) and evaluate their osteogenic stimulation ability along with localized bone regeneration ability. Here, the spontaneously synthesized Qu-SeNPs showed uniform size distribution and rough flower-shaped morphology. The confocal images indicate improved cellular uptake and even cellular distribution of Qu-SeNPs in osteoblasts, resulting in increased osteogenic activity as indicated by enhanced expression of early and late osteoprogenitor differentiation markers. Qu-SeNPs also decreased osteoblasts' RANKL/OPG ratio and inhibited osteoclast formation. Mechanistically, Qu-SeNPs activate critical signaling pathways, including WNT and BMP, and utilize the miR-206/Connexin43 pathway to enhance osteogenesis. In vivo, experiments utilizing a drill-hole bone defect model in mice indicate that hydrogel-mediated localized delivery of Qu-SeNPs significantly accelerates bone defect healing. Thus, well-characterized and mechanistic, detailed synthesized Qu-SeNPs can restore bone remodeling, and Qu-SeNPs embedded in hydrogels may improve Qu cellular uptake and bioavailability in clinical settings, enabling innovative orthopedic and regenerative therapies for bone loss/defects.

The increase in metabolic dysfunction-associated steatotic liver disease (MASLD) and its progression to metabolic dysfunction-associated steatohepatitis (MASH) is a worldwide healthcare challenge. Heterogeneity between men and women in the prevalence and mechanisms of MASLD and MASH is related to differential sex hormone signalling within the liver, and declining hormone levels during aging. In this study we used biochemically characterised pluripotent stem cell derived 3D liver spheres to model the protective effects of testosterone and estrogen signalling on metabolic liver disease 'in the dish'. We identified sex steroid-dependent changes in gene expression which were protective against metabolic dysfunction, fibrosis, and advanced cirrhosis patterns of gene expression, providing new insight into the pathogenesis of MASLD and MASH, and highlighting new druggable targets. Additionally, we highlight gene targets for which drugs already exist for future translational studies.

Parkinson's disease (PD) starts decades before symptoms appear, usually in the later decades of life, when age-related changes are occurring. To identify molecular changes early in the disease course and distinguish PD pathologies from aging, we generated Drosophila expressing alpha-synuclein (αSyn) in neurons and performed longitudinal bulk transcriptomics and proteomics on brains at six time points across the lifespan and compared the data to healthy control flies as well as human post-mortem brain datasets. We found that translational and energy metabolism pathways were downregulated in αSyn flies at the earliest timepoints; comparison with the aged control flies suggests that elevated αSyn accelerates changes associated with normal aging. Unexpectedly, single-cell analysis at a mid-disease stage revealed that neurons upregulate protein synthesis and nonsense-mediated decay, while glia drive their overall downregulation. Longitudinal multi-omics approaches in animal models can thus help elucidate the molecular cascades underlying neurodegeneration vs. aging and co-pathologies.

Aging is a principal driver of cardiomyopathy, characterized by mitochondrial dysfunction, oxidative stress, and progressive telomere shortening in cardiomyocytes. These pathological changes impair cellular bioenergetics and regenerative capacity, accelerating cardiac deterioration. However, targeted interventions to mitigate these effects remain limited. This research investigates the therapeutic potential of CISD1 activation as a novel strategy to counteract aging-associated cardiac decline. Using advanced Immunoinformatic approaches, including molecular docking, protein structure modelling, and molecular dynamics simulations, we assess the role of CISD1 upregulation in enhancing mitochondrial bioenergetics, reducing oxidative stress, and preserving telomere integrity. Our Immunoinformatic findings reveal that CISD1 activation stabilizes mitochondrial function, mitigates oxidative damage, and slows telomere attrition, thereby sustaining cardiomyocyte function and delaying cellular senescence. Our research identifies 4'-Methoxy-3', 5,7-trihydroxy flavanone as a potential small-molecule activator of CISD1, offering a promising pharmacological approach to modulate mitochondrial dynamics in aging cardiomyocytes. By directly addressing the mechanistic link between CISD1, mitochondrial stability, and telomere preservation, this research bridges a critical gap in understanding age-related cardiomyopathy and provides a foundation for targeted therapeutic interventions. Our findings suggest that CISD1 activation could restore cellular homeostasis in aged cardiac tissues, reducing the risk of heart failure and other aging-related cardiovascular diseases. These insights advance age-related disease intervention strategies by targeting fundamental molecular pathways involved in cardiomyocyte aging.

The autophagy-lysosomal system comprises a highly dynamic and interconnected vesicular network that plays a central role in maintaining proteostasis and cellular homeostasis. In this study, we uncovered the deubiquitinating enzyme (DUB), dUsp45/USP45, as a key player in regulating autophagy and lysosomal activity in Drosophila and mammalian cells. Loss of dUsp45/USP45 results in autophagy activation and increased levels of V-ATPase to lysosomes, thus enhancing lysosomal acidification and function. Furthermore, we identified the actin-binding protein Coronin 1B (Coro1B) as a substrate of USP45. USP45 interacts with and deubiquitinates Coro1B, thereby stabilizing Coro1B levels. Notably, the ablation of USP45 or Coro1B promotes the formation of F-actin patches and the translocation of V-ATPase to lysosomes in an N-WASP-dependent manner. Additionally, we observed positive effects of dUsp45 depletion on extending lifespan and ameliorating polyglutamine (polyQ)-induced toxicity in Drosophila. Our findings highlight the important role of dUsp45/USP45 in regulating lysosomal function by modulating actin structures through Coro1B.

Aging is driven by fundamental mechanisms like oxidative stress, telomere shortening and changes in DNA methylation, which together prepare the ground for age-related diseases. Botanical extracts, rich in bioactive phytoconstituents, represent a promising resource for developing therapies that target these mechanisms to promote healthy aging. This study explores the geroprotective potential of Monarda didyma L. extract. In vitro analyses revealed the extract's strong antioxidant activity, ability to reduce telomere shortening, and capacity to protect against DNA damage, thereby decreasing cellular senescence and improving endothelial function. The randomized, double-blind clinical trial demonstrated that daily oral supplementation with the extract significantly improved leukocyte telomere length (LTL) and stabilized DNA methylation age (DNAmAge) in the intervention group, while the placebo group experienced accelerated epigenetic aging and hypermethylation of critical age-related genes (ELOVL2 and FHL2). The intervention group also reported enhanced quality of life, particularly in the physical domain, along with improved movement and quality sleep indices detected by questionnaire and wearable sensors. These compelling findings position Monarda didyma L. extract as a powerful candidate for future geroprotective therapies, with the potential to significantly impact healthy aging.

The accumulation of senescent cells (SEN) with aging produces a chronic inflammatory state that accelerates age-related diseases. Eliminating SEN has been shown to delay, prevent, and in some cases reverse aging in animal disease models and extend lifespan. There is thus an unmet clinical need to identify and target SEN while sparing healthy cells. Here, we show that the lysosomal membrane protein Lysosomal-Associated Membrane Protein 1 (LAMP1) is a membrane-specific biomarker of cellular senescence. We have validated selective LAMP1 upregulation in SEN in human and mouse cells. Lamp1+ cells express high levels of prototypical senescence markers p16, p21, Glb1, and have low Lmnb1 expression as compared to Lamp1- cells. The percentage of Lamp1+ cells is increased in mice with fibrotic lungs due to bleomycin instillation. Finally, we use a dual antibody-drug conjugate (ADC) strategy to eliminate LAMP1+ senescent cells.

The progressive loss of cerebral white matter during aging contributes to cognitive decline, but whether reduced blood flow is a cause or consequence remains debated. Using deep multi-photon imaging in mice, we examined microvascular networks perfusing myelinated tissues in cortical layer 6 and corpus callosum. We identified sparse, wide-reaching venules, termed principal cortical venules, that exclusively drain deep tissues and resemble vasculature at the human cortex and U-fiber interface. Aging involved selective constriction and rarefaction of capillaries in deep branches of principal cortical venules. This resulted in mild hypoperfusion that was associated with microgliosis, astrogliosis and demyelination in deep tissues, but not upper cortex. Inducing a comparable hypoperfusion in adult mice using carotid artery stenosis triggered a similar tissue pathology specific to layer 6 and corpus callosum. Thus, impaired capillary-venous drainage is a contributor to hypoperfusion and a potential therapeutic target for preserving blood flow to white matter during aging.

Among epigenetic modifiers, telomeres represent attractive modulators of the genome in part through position effects. Telomere Position Effect-Over Long Distances (TPE-OLD) modulates gene expression by changes in telomere-dependent long-distance loops. To gain insights into the molecular mechanisms of TPE-OLD, we performed a genome-wide transcriptome and methylome analysis in proliferative fibroblasts and myoblasts or differentiated myotubes with controlled telomere lengths. By integrating omics data, we identified a common TPE-OLD dependent cis-acting motif that behaves as an insulator or enhancer. Next, we uncovered trans partners that regulate these activities and observed the consistent depletion of one candidate factor, RBPJ, at TPE-OLD associated loci upon telomere shortening. Importantly, we confirmed our findings by unbiased comparisons to recent Human transcriptomic studies, including those from the Genotype-Tissue Expression (GTEx) project. We concluded that TPE-OLD acts at the genome-wide level and can be relayed by RBPJ bridging Alu-like elements to telomeres. In response to physiological (i.e., aging) or pathological cues, TPE-OLD might coordinate the genome-wide impact of telomeres through recently evolved Alu elements acting as enhancers in association with RBPJ.

Substantial heterogeneity in cognitive ageing is well documented. Such heterogeneity has been attributed to individual differences in brain maintenance - i.e., the relative preservation of neural resources in ageing. However, large-scale longitudinal evidence is lacking. We pooled data from three population-based Swedish cohorts (Betula, N = 196; SNAC-K, N = 472; H70, N = 688; aged 60-93 years at baseline, follow-up duration up to 7 years) to assess whether global brain maintenance is associated with better preserved cognition in ageing, and to identify lifestyle predictors of brain maintenance. In each cohort, global brain integrity was indexed by the volume of the lateral ventricles (adjusted for total intracranial volume), and general cognitive function based on a principal component analysis of four age-sensitive cognitive domains. Participants were classified into subgroups of low (i.e., \'aged\') versus high (i.e., \'youth-like\') brain integrity based on ventricular volume estimates available for a younger reference sample in one of the cohorts (Betula, 25-55 years, N = 60). Subgroup differences in cognition at baseline and over the follow-up were assessed with ANCOVAs and linear mixed effects models. Logistic regressions were used to examine lifestyle predictors of brain maintenance. Across cohorts, 881 individuals (64.97%) were classified into the high brain integrity subgroup at baseline and 409 individuals (49.82%) over the follow-up. Maintenance of more youth-like brain integrity was associated with better baseline cognition (p < .001) and less cognitive decline longitudinally (p < .001). Moreover, lower cardiovascular disease (CVD) risk and the absence of diabetes predicted brain maintenance at baseline (CVD risk, OR = 0.80, 95% CI [0.68, 0.93]; diabetes, OR = 0.39, 95% CI [0.26, 0.59]) and over the follow-up (CVD risk, OR = 0.79, 95% CI [0.64, 0.96]; diabetes, OR = 0.53, 95% CI [0.29, 0.94]). These findings underscore brain maintenance as a key determinant of cognitive ageing and highlight the importance of managing cardiovascular and metabolic disease risk factors for promotion of brain and cognitive health in later life.

Reactive oxygen species (ROS)-induced cell damage contributes to many diseases. However, ROS also contribute to cell signaling and immune defences. As ubiquitous thiol peroxidases, peroxiredoxins (Prdx) play integral roles in balancing ROS functions. High levels of Prdx6 are associated with increased metastasis and resistance to chemotherapy, rendering Prdx6 a therapeutic target for treatment of a broad range of cancers. However, Prdx6, has additional activities, in lipid signalling and selenocysteine metabolism, and it remains unclear how Prdx6\'s thiol peroxidase activity contributes to disease or ageing. Here we have investigated the role/s of Prdx6 in the stress responses and ageing of the nematode worm Caenorhabditis elegans. Unexpectedly, we have found that C. elegans lacking prdx-6, have an increased resistance to oxidative stress and extended lifespan under some conditions. Moreover, prdx-6 mutant worms are also more resistant to infection with two opportunistic human pathogens; the gram-positive bacteria Staphylococcus aureus and the dimorphic yeast Candida albicans. Our data suggest that increased ROS levels in prdx-6 mutant worms lead to increased cell death in the germ line, and increased expression of the Flavin monooxygenase, FMO-2 in other tissues. FMO-2 has a conserved pro-survival function and is upregulated by the NHR-49(PPAR{beta}/HNF4) transcriptional regulator in response to various stresses, including peroxides and S. aureus infection. Here we reveal that fmo-2 expression is also increased as an NHR-49-dependent protective response to C. albicans. Thus, in addition to its anti-ageing role, FMO-2 protects C. elegans against both fungal and bacterial infections. Accordingly, we propose that elevated fmo-2 expression contributes to the increased stress resistance, lifespan and innate immunity of prdx-6 mutant animals. These findings further illustrate the complex roles that ROS/PRDX can play in stress resistance, immunity and ageing.