npj Aging

Biological aging is heterogeneous across organ systems, yet whether CT-derived abdominal aging provides prognostic value beyond routine clinical data and whether organ decomposition adds beyond a unified estimate remains untested. We developed and evaluated organ-specific and ensemble biological age models from radiomic features across five abdominal organs in 68,675 CT scans from 32,883 subjects, evaluated on alignment with chronological age of healthy subjects (nested cross validation: MAE=3.68 years, R^2=0.90). In sequential analyses restricted to adults aged 20-60 years which is the stratum of strongest BAG-disease association, ensemble biological age gaps provided incremental prognostic value beyond demographic covariates for all-cause disease and mortality (Delta C-index=0.141, 0.051) and beyond routine blood biomarkers (Delta C-index=0.048), confirming CT-derived aging captures structural information beyond laboratory markers. Organ-specific biological age added incremental prognostic value beyond ensemble selectively for focal diseases: cardiovascular (aorta, Delta C-index=0.091) and hepato-pancreatic (pancreas, Delta C-index=0.096). These findings establish a hierarchical organization of CT-derived biological aging, positioning routine CT as a source that adds prognostic value to existing clinical biomarkers.

BackgroundThe continuous rise in life expectancy introduces a central challenge of new longevity, ensuring that the additional years gained are accompanied by the preservation of cognitive function and quality. MethodsWe propose a modeling framework for multi-domain brain age derived from a repertoire of digital cognitive metrics. The model, based on Ridge regression with Leave-One-Out cross-validation, was trained in a cohort of 394 healthy controls (HC; 307 women and 87 men; mean age 30.0 {+/-} 12.5 years; range 17-64). ResultsThe model achieved a correlation between chronological age and predicted age of r = 0.942 with a mean absolute error of 3.05 years. When applied to three additional clinical cohorts, multiple sclerosis (N = 70), traumatic brain injury (N = 23), and depression (N = 18), the model detected significant accelerated cognitive aging across all conditions, with processing speed emerging as the dominant contributor to accelerated aging, albeit with varying degrees of concentration across pathologies. ConclusionsDigital cognitive metrics provide an accessible, non-invasive, and scalable biomarker for tracking brain aging, with strong potential for informing personalized neuropsychological interventions and for integration into active aging frameworks within the context of modern longevity.

The relationship between age-related genetic factors and health conditions has become a pivotal focus in aging research, particularly as the World Health Organization (WHO) delineates the leading global causes of mortality. However, the direct impact of age-related genes on the leading cause of death remains poorly understood. To investigate this gene-aging relationship, we analyzed protein-protein interactions using gene set enrichment analysis (GSEA) of a set of 307 age-related genes previously curated. The results indicated significant associations with 113 diverse disease categories, while adhering to a stringent false discovery rate (FDR) threshold of less than 1 x 10-5. Due to the difficulties in aligning the disease categories with WHOs leading causes of death, we reclassified the WHO categories using the more precise nomenclature specified in the 11th Revision of the International Classification of Diseases (ICD-11). The age-related genes account for the leading causes of death, with the exceptions being two infectious communicable diseases, tuberculosis and COVID-19. They impact the cardiovascular system, brain, lungs, and the whole body, while this study could not identify death by aging, which is not a well-defined medical cause of death. Furthermore, we identified a set of 15 recurring genes shared among multiple diseases, including TNF, AKT1, IL6, CDK2A, APOE, and TP53. This gene set was enriched for several disease categories, including cancer, inflammatory diseases, metabolic disorders, and neurodegenerative diseases. Additionally, it shows significant enrichment in various biological categories, with the regulation of nitric oxide activity being the most prominent; other enriched categories include the regulation of microRNA, lipid and carbohydrate metabolism, smooth muscle cell proliferation, insulin signaling, and phosphatidylinositol-3 kinase (PI3K) signaling. The findings suggest that the recurring genes act as pleiotropic hubs, influencing multiple leading causes of death, while other genes are more specific to each disease category.

IntroductionLife expectancy for people with type 1 diabetes has increased due to improved treatment of diabetes and its comorbidities, allowing many to reach old age. Still, we lack knowledge of how individuals with type 1 diabetes age. On one hand, those who reach older age can be considered survivors, but on the other hand their long-standing diabetes might still exhibit negative impacts on their health and functional ability. Healthy ageing is the World Health Organizations priority for this decade. The focus has shifted from chronological age to functional ability, which reflects the ability of individuals to perform meaningful activities. Functional ability is shaped by intrinsic capacity, the environment, and their interaction. Intrinsic capacity encompasses five main domains: cognition, vitality, sensory function, locomotion, and psychological domain. This observational study aims to assess how this vulnerable group of individuals with type 1 diabetes age and to identify factors that contribute to their healthy ageing, intrinsic capacity, and its domains. Methods and analysisThe FinnDiane LifeOne Study is a prospective observational cohort study. We aim to recruit a minimum of 300 individuals with type 1 diabetes from the FinnDiane Study, aged >65, and a minimum of 100 matched controls without insulin-dependent diabetes. The cohort will be comprehensively characterized, including clinical assessment, laboratory tests, questionnaires, and a geriatric assessment of different aspects of functioning ability, with five years intervals. We will compare the individuals with type 1 diabetes to their matched controls. For those with type 1 diabetes, we will further assess which factors from the FinnDiane baseline and trajectories during follow-up predict healthy ageing in above 65-year-olds. Ethics and disseminationThe LifeOne study protocol is approved by the Ethics Committee of HUS Helsinki University Hospital (HUS/4387/2023) and the study adheres to the Declaration of Helsinki. Written informed consent is obtained from each participant. Findings will be published in international peer-reviewed journals with an open access choice. The study is registered at ClinicalTrials.gov with ID NCT07289204. STRENGTHS AND LIMITATIONS OF THE STUDYO_LIThis is a prospective observational cohort study with a matched control group. C_LIO_LIFor the participants with type 1 diabetes, we have unique and comprehensive longitudinal clinical and genetic data available from approximately participants middle age, enabling identification of factors that contribute to their healthy ageing, while accounting for the competing risk of death. C_LIO_LIThe cohort is thoroughly characterised regarding diabetes, cardiometabolic health, lifestyle, psychosocial factors, and includes a geriatric assessment, thereby enabling comparison of impact of ageing between individuals with type 1 diabetes and controls without insulin-dependent diabetes. C_LIO_LIThe cohort is Caucasian with recruitment from Southern Finland, potentially limiting generalisability to other more ethnically diverse populations. C_LI

Centenarians exhibit marked heterogeneity in biological aging despite their exceptional longevity. To identify biological factors linked to survival at extreme old age, we examined DNA methylation-based measures of aging in 247 cognitively healthy Dutch centenarians using PacBio long-read methylation sequencing. Age acceleration derived from the DNA methylation clock GrimAge emerged as a robust predictor of mortality (HR = 1.60, 95% CI: 1.28-2.00), independent of markers previously associated with mortality in centenarians, such as Mini-Mental State Examination (MMSE) scores (HR = 0.68, 95% CI: 0.56-0.84) and plasma neurofilament light chain (NfL) levels (HR = 1.29, 95% CI: 1.09-1.53). GrimAge acceleration showed limited association with phenotypes related to brain aging, including cognitive performance, neurodegeneration- and Alzheimers disease-related plasma biomarkers, and neuropathological measures. By contrast, it was associated with hematological markers consistent with age-related myeloid shift, although these did not fully account for its association with survival. Together, these findings suggest that GrimAge reflects a mortality-associated dimension of aging that is distinct from brain aging and remains informative even at extreme old age.

Aging can alter macrophage functions through changes in intracellular processing, mitochondrial activity, and chronic inflammatory activation; however, whether aging-associated macrophage deregulation contributes to tumor-associated multinucleated syncytial formation remains poorly understood. Here, we investigated the role of aging macrophages in promoting tumor-like multinucleated syncytia and explored the underlying metabolic mechanisms. Immunohistochemical analyses of metastatic tissue sections from patients with prostate, breast, and lung cancers demonstrated enrichment of CD68+/panCK+ multinucleated tumor-like osteoclast syncytia in elderly patients. Using ex vivo co-culture systems, aged bone marrow-derived macrophages exhibited significantly increased propensity to generate multinucleated syncytia containing proliferative Ki67-positive cancer-associated nuclei. These syncytia displayed attenuated mitochondrial oxidative phosphorylation (OXPHOS) programs characterized by reduced oxygen consumption rates and decreased expression of mitochondrial respiratory proteins, such as ATP5a and SDHB. Pharmacologic inhibition of STAT6 further enhanced syncytial formation and suppressed OXPHOS-associated programs, whereas treatment with the EP2 antagonist C52 partially restored mitochondrial gene expression and reduced syncytial formation. Together, these findings identify a previously unrecognized aging-associated mechanism linking macrophage deregulation, attenuated STAT6-associated mitochondrial programs, and tumor-like multinucleated syncytial formation.

The short-lived annual fish Nothobranchius furzeri (Nfu) is a powerful vertebrate model for aging research due to its rapid lifespan and accelerated development of age-associated phenotypes, including gliosis and lipofuscin accumulation. Here, we investigated the effects of dietary 1,3-1,6 {beta}-glucans (BGs), natural polysaccharides derived from Saccharomyces cerevisiae, on aging-related processes across multiple tissues, with particular focus on the brain. Chronic treatment with BG-fortified food reduced several hallmarks of aging in multiple organs. Mechanistically, BG treatment modulated pathways associated with autophagy, lysosomal function, protein oxidation, and inflammation. Both acute and chronic BG administration increased autophagic activity in the aging brain, although lipofuscin accumulation was not affected. To assess whether BGs act directly on neural tissue, we established an ex-vivo Nfu brain culture system that recapitulates the age-dependent decline in autophagy observed in vivo. In this model, acute BG treatment restored impaired autophagy and promoted mitochondrial and lysosomal biogenesis in aged brains. Proteomic analyses revealed increased mitochondrial respiration and modulation of V-ATPase components involved in autophagosome acidification. Depletion of microglia reduced but not eliminated this effect, suggesting direct action of BGs on neurons. To verify the validity of these findings in humans, we performed BG treatment in human iPSC-derived neurons under conditions of impaired autophagy and found an increase in survival. Together, these findings identify {beta}-glucans as modulators of autophagy, mitochondrial function, and inflammation, highlighting their potential to promote healthy aging.

Brain age models - machine-learning predictions of chronological age from brain imaging - are widely interpreted as markers of accelerated brain aging. Here we show that this interpretation cannot be supported. Because these models are trained to predict chronological age, they prioritize features that change similarly across people and actively downweight features that capture differences in individual trajectories, precisely the property an aging-rate biomarker must have. In effect, brain age models are optimized to ignore the very signal they are used to study, thereby risking converting stable between-person differences into apparent accelerated aging. Using theoretical analysis, simulations, and longitudinal MRI, we confirm both predicted failure modes: brain age models indicated "accelerated aging" in participants with low birth weight despite no longitudinal evidence, while a single hippocampal volume measurement was more sensitive than the brain age gap to tau-related neurodegeneration. Across much of the brain age literature, it is therefore not possible to determine whether reported effects reflect brain aging or stable anatomical differences, and the brain age gap should not be interpreted as a marker of brain aging or brain health. We propose alternative strategies that reorient prediction targets from shared age-related patterns to individual differences in change.

Autophagy is widely proposed to decline with age; however, direct evidence for this across cell and tissue types in humans remains limited. Furthermore, it remains unknown whether interventions that improve physiological health during aging can modify autophagic activity in humans. Here, we performed transcriptomic and functional autophagy analyses across subject-matched human cell types from a healthy aging cohort spanning the adult lifespan. RNA-seq of primary dermal fibroblasts and induced neurons (iNs) revealed increased transcription of many autophagy-related genes with age, most markedly in fibroblasts. The impact of age on autophagic activity, measured using autophagy flux assays, was cell type- and sex-dependent, and uncoupled from autophagy-gene transcription. Autophagy flux decreased with age in male fibroblasts, was unchanged in female fibroblasts, and increased in female iNs. In freshly isolated peripheral blood mononuclear cells (PBMCs), autophagy flux became more heterogeneous with age and trended higher in older individuals, independent of sex. Although autophagy flux levels did not match across different cell types, higher autophagy flux in all cell types was associated with reduced physical function in older adults ([≥]70 years). Importantly, autophagy flux decreased following 12 weeks of mild exercise in parallel with improved physical function. These findings indicate that autophagy is regulated in a cell type-, sex-and physiological function-dependent manner during human aging, and highlight PBMC autophagy flux as a potentially modifiable, blood-accessible readout of physiological state in older adults.

BackgroundSkin aging is multifactorial, and finished multi-ingredient oral beauty supplements require dedicated clinical evaluation because their effects cannot be inferred from individual ingredient data alone. ObjectiveTo explore, in a 56-day single-arm open-label study, whether daily oral intake of NatureU(R) Mind Care BeautyU Caps is associated with within-participant changes in crows-feet wrinkle count (primary endpoint), stratum corneum hydration (secondary endpoint), and additional exploratory skin-aging parameters in adult women. MethodsA single-center, open-label, single-arm exploratory study enrolled 33 healthy women aged 36-56 years; 31 completed the protocol and were included in the completer efficacy analysis. Participants took one capsule orally once daily for 56 consecutive days. Assessments were performed at D0, D28 and D56 using PRIMOS CR, Corneometer CM 825, Cutometer MPA580, Glossymeter, Colorimeter CL400, Mexameter MX18, VISIA CR, DermaScan and a structured self-assessment. ResultsPRIMOS CR crows-feet wrinkle count fell from 965 {+/-} 334 at D0 to 514 {+/-} 171 at D56 (within-participant change -46.74%; nominal P = 0.001). Corneometer hydration rose from 44.3 {+/-} 7.8 to 70.3 {+/-} 9.9 (+58.69%; nominal P = 0.001). Exploratory parameters (other wrinkle metrics, elasticity, gloss, ITA{degrees}, melanin, spots, dermal thickness/density) generally moved in directions consistent with the primary signal. No adverse reactions were reported. ConclusionIn this open-label, single-arm exploratory study, daily NatureU(R) Mind Care BeautyU Caps was associated with within-participant reductions in crows-feet wrinkle count and increases in stratum corneum hydration over 56 days. Findings are hypothesis-generating; randomized placebo-controlled trials are required.

Aging is accompanied by a progressive decline in physiological function that contributes to chronic disease development. Biological clocks estimated from high-dimensional clinical and biological measurements may provide more granular tracking of the aging processes. Current biological clocks, however, have limited cross-ancestry generalizability and clinical applicability. Here, we developed a multi-ancestry biological clock (ClinBAG) using 22 routine blood and anthropometric biomarkers in 14,328 age- and sex-balanced individuals from the All of Us Research Program. We tested the association of ClinBAG with 434 traits and evaluated its ability to predict incident disease in 152,733 non-overlapping individuals. We also conducted genome-wide association studies in European (N=74,675), African (N=22,315), and Admixed American ancestry individuals (N=19,940). Among 190 neurological phenotypes, elevated ClinBAG was associated with cognitive decline, increased incidence of dementia (HR=1.020, p=1.6x10-5) and Parkinson's disease (HR=1.014, p=0.023), and decreased risk of migraine (HR=0.991, p=8.7x10-4). We also identified common (NPRL3) and ancestry-specific genetic loci (HBB in African-ancestry and FADS1/FADS2 in European-ancestry) for ClinBAG. Single-cell enrichment revealed that ClinBAG-associated genes are overexpressed in double-negative (DN) T cells in an age-dependent manner. This study presents a clinically applicable multi-ancestry biological age clock predicting neurological disease risk. Our findings also uncover population-specific genetic drivers, particularly involving erythropoiesis and DN T-cell-mediated neuroinflammation.

The slowing of executive function and memory impairment are the leading hallmarks of cognitive decline with age. The exact cause of this change is unknown and is the focus of aging research. Expression levels of Vesicle Associated Membrane Protein 2 (VAMP2)/Synaptobrevin-2 (syb2) are decreased with age. Here we report results from a novel transgenic mouse model (TgV2) that overexpresses syb2. We hypothesized that overexpression of syb2 improves synaptic function during aging, thus it delays dementia. Aged TgV2 mice, which maintained syb2 levels, performed better in spatial memory tests than 2-year-old WT control mice, which had lost half of syb2 due aging. In hippocampal CA1 synapses of aged TgV2 mice, long-term potentiation was increased. These effects of maintained syb2 levels were beneficial for both males and females providing improved synaptic plasticity. These results indicate that overexpression of syb2 supports cognitive function throughout the aging process and better resist age-related synaptic dysfunction.

We have recently demonstrated that treatment of aged mice with a pan-ERR agonist reverses age-related increase in urinary albumin, decrease in podocyte density, impaired mitochondrial function, and inflammation. The contribution of individual isoforms of ERRs however has not been determined. Since the aging kidney showed a possible compensatory increased expression of ERR{gamma} in the podocytes, in the face of decreased ERR expression, in the present study we aimed to determine the role of ERR{gamma} in aging podocyte. To this end, we cross bred ERR{gamma} floxed mice with podocin-Cre mice to achieve a podocyte-specific ERR{gamma} deletion. While these mice at 3 months of age showed no effect on albuminuria compared to the wild type, when the mice were aged to 21 months of age, there was a significant increase in albuminuria and decrease in podocyte density. Furthermore, we found that the podocyte deletion of ERR{gamma} primarily targeted the expression of mitochondrial biogenesis regulator PGC-1, and mitochondrial fatty acid oxidation enzymes CPT1a and MCAD in the kidney. Electron Microscopy (EM) revealed thickened glomerular basement membrane and diffuse podocyte foot process effacement, as well as severe mitochondrial damage including cristae abnormalities, fragmentation, and changes indicative of altered fusion and fission dynamics. Fluorescence Lifetime Imaging Microscopy (FLIM) to determine NADH and FAD lifetimes indicate a metabolic shift from mitochondrial oxidative phosphorylation towards glycolysis, and decrease in mitochondrial redox capacity. Considering a significantly decreased expression of ERR in aging podocytes plus its traditional role in mitochondrial function, these studies using podocyte ERR{gamma} deletion suggested an overlapping mechanism for ERR/ERR{gamma} to act as modulators of age-related mitochondrial dysfunction and age-related kidney disease.

Risk assessment in clinical practice depends largely on clinical phenotypes, including age, sex, body mass index, blood pressure and comorbidities. Routine laboratory data remain underutilised despite their accessibility and low cost. Using data from the Singapore Longitudinal Ageing Studies (n = 5,409; follow-up median 11.4 years), we developed a mortality prediction model based on routine laboratory biomarkers. We derived a biological age (age quotient, or AQ) score, and investigated its role as a mediator between lifestyle risk factors and mortality. Both models and association analyses were validated in the US National Health and Nutrition Examination Survey (n = 6,593) and UK Biobank (n = 290,949) cohorts. AQ was significantly elevated in deceased individuals (P<0.0001). AQ acceleration was also observed (P<0.0001). In overall survival discrimination, AQ outperformed chronological age (C-index 0.629 [SE 0.011] vs 0.606 [SE 0.011]), indicating superior prognostic prediction. Additionally, incorporation of AQ into a baseline model containing chronological age resulted in an improvement in model fit (likelihood ratio test, P<0.0001), consistent with incremental predictive value for mortality beyond chronological age alone. Mediation analysis supports a partial mediating role for AQ in the relationship between lifestyle factors and mortality. In a 57-patient subset, higher AQ was associated with increased TET2 clonal hematopoiesis burden ({beta}{approx}0.016 per +1 AQ year), suggesting a potential link between AQ acceleration, CH risk and diseases of aging, requiring validation in larger cohorts. We identified differential associations between lifestyle factors and groups of biological age components, indicating selective effects across biological systems. These findings provide an evidence-based framework for earlier and more accurate identification of high-risk individuals, offering a practical and easy-to-implement tool to inform preventive strategies.

Spinal fractures are an important contributor to disability worldwide, particularly in aging populations. However, comprehensive long-term comparisons between China and other major economies remain limited. Using data from the Global Burden of Disease (GBD) 2021 study, we analyzed temporal trends in the incidence, prevalence, and years lived with disability (YLDs) of spinal fractures in China and the overall G20 from 1990 to 2021. Age-standardized rates were assessed using Joinpoint regression and age-period-cohort analysis. Future burden through 2050 was projected using autoregressive integrated moving average modeling, and decomposition analysis was performed to quantify the contributions of demographic and epidemiological factors. Between 1990 and 2021, China experienced substantial increases in absolute burden. Incident cases increased by 52.27%, prevalent cases by 113.66%, and YLDs by 107.21%. The age-standardized prevalence rate (ASPR) and age-standardized YLD rate (ASYR) increased significantly, whereas the age-standardized incidence rate (ASIR) showed a non-significant upward trend. In contrast, the overall G20 aggregate showed increasing absolute case numbers but significantly declining age-standardized rates. Age-period-cohort and age-specific analyses indicated that older adults represented the main burden-bearing population. Projections suggested that Chinas ASIR may decline by 2050, whereas prevalence and YLD burden, particularly among males, may remain relatively high compared with the overall G20 level. Decomposition analysis identified population aging as the major driver of burden growth. China experienced a rising burden of spinal fractures over the past three decades, in contrast to declining age-standardized trends in the overall G20 aggregate. These findings highlight the substantial role of population aging in shaping spinal fracture burden and provide epidemiological evidence for prevention planning and aging-related health policy.

BackgroundHemoglobin A1c (HbA1c), an important diagnostic biomarker for type 2 diabetes (T2D), is also associated with aging, cognitive performance, and mortality. To identify epistatic interactions, we assessed 133 known gene variants associated with HbA1c among 3,778 non-diabetic subjects of European ancestry in the Long Life Family Study (LLFS). MethodsWe applied Bayesian Imputation Based Association Mapping (BIMBAM) to identify significant pairwise epistatic interactions among genetic variants that were previously shown to be associated with levels of HbA1c. To take into account confounding effects, we adjusted age, sex, field centers, body mass index (BMI), and genetic principal components (PCs). ResultsThis analysis yielded seven pairs with log10(BF)>10; of those, six pairs were confirmed using a full-term mixed regression model. Specifically, these included significant interactions of HK1-rs17476364 with variants in GCK (rs2971670, rs4607517) or G6PC2 (rs560887), as well as between HK1-rs16926246 and the same variants (P values for each term [&le;] 7.14x10-3). All epistatic interactions between HK1 and GCK, and between HK1 and G6PC2 were replicated in two large independent studies (namely, Framingham Offspring Study, P < 0.05; Health and Retirement Study, P < 0.05). ConclusionThe present study revealed that HK1 and GCK interact to contribute to regulating levels of HbA1c and are likely to be involved in molecular mechanisms underlying healthy aging processes.

BackgroundDNA methylation-based biomarkers have been widely used to predict biological age; however, most blood-derived data have been used in most existing models, and whether cheek mucosa can serve as an alternative indicator for methylation-based estimation of aging-related and clinical phenotypes is unclear. MethodsDNA methylation profiles from cheek mucosa and whole blood of 186 Japanese adults were analyzed using Illumina Infinium Methylation Screening Array (MSA). Models were constructed to predict chronological age, phenotypic age, and clinical laboratory biomarkers from cheek mucosa- and blood-derived methylation data. In addition to applying the ordinary elastic net method, a two-stage residual learning method incorporating existing blood-based epigenetic clocks was applied for more accurate prediction of biological age. Sex-stratified analyses and comparisons of selected CpG features across sexes and tissues were performed. ResultsCheek mucosa-derived MSA methylation data enabled accurate prediction of chronological age (R = 0.965) and phenotypic age (R = 0.964) using the two-stage method. The performance gain achieved by the two-stage approach was greater for phenotypic age than for chronological age. Multiple clinical laboratory biomarkers could be predicted using cheek mucosa-derived methylation data, particularly after sex stratification, including inflammatory, metabolic, thyroid-related, and sex hormone-related markers. Most biomarkers that could be predicted using blood-derived methylation data were also predicted using cheek mucosa-derived methylation data. However, the CpG sites selected for prediction showed minimal overlap across sexes and tissues despite overlap in the corresponding predictable phenotypes. ConclusionsCheek mucosa-derived DNA methylation profiles measured using the MSA can predict chronological age, phenotypic age, and multiple clinically relevant laboratory biomarkers, supporting the utility of cheek mucosa as a less invasive alternative for methylation-based assessment of biological aging and systemic physiological state.

Aging is an inevitable risk factor for cardiovascular disease. Profound understanding of mechanisms underlying the early stages of cardiovascular aging is essential for the development of novel therapeutics. Therefore, animal models which closely reflect the human condition are highly sought after. Here, we investigated natural cardiovascular aging in a non-human primate, comparing healthy young-adult and aged common marmosets (Callithrix jacchus). Despite preservation of most cardiac functional parameters in aged animals, significant histological alterations were found including fibrosis and microvascular rarefaction. Molecular phenotyping by single-nuclei RNA-sequencing revealed activation of cardiac stress, pro-inflammatory and fibrotic gene programs in aged hearts. Importantly, proteomic analysis of cardiac extracellular vesicles revealed a cardioprotective cargo in young animals while functionally demonstrating pro-angiogenic properties on human cardiac microvascular endothelial cells. Finally, large vessel atherosclerosis was strikingly evident in aged animals and elucidated by bulk RNA-sequencing. Overall, the aging marmoset offers a great potential for translational cardiovascular research.

Autophagy is a hallmark of aging, but autophagy-related proteins have not been exclusively targeted to attenuate the progressive decline in physical function associated with aging. Here, we combined Tat-Beclin1, an autophagy agonist, and endurance training to determine whether Tat-Beclin1 enhances exercise adaptation in old male mice. Tat-Beclin1 was administered intraperitoneally (TB group, 15 mg/kg, 2x/week) as a standalone therapy, or in combination with endurance training (TB+Exe group, 70% of maximal running speed 3x/week) for 1 month in 23-month-old male C57BL/6J mice. Control groups were age-matched cage controls and exercise-only groups. Animals were assessed for grip strength, endurance capacity on a treadmill, and balance and coordination on a rotarod. Gastrocnemius/plantaris (G/P) and tibialis anterior muscles were harvested for western blotting, myofiber typing, and proteomic profiling (G/P only). TB+Exe led to significant increases in grip strength, endurance capacity, and balance and coordination performance beyond those observed in the TB and Exe groups alone. Autophagy markers, including Beclin1, the LC3B-II/I ratio, and p62, did not differ among groups. A proteomic analysis of the G/P muscle revealed that TB upregulated biological processes involved in muscle contraction and adaptation, whereas TB+Exe increased mitochondrial bioenergetic processes and, surprisingly, upregulated acute inflammatory responses, including proteins such as haptoglobin and orosomucoid-1. We conclude that combining Tat-Beclin1 and endurance training may represent a new approach to attenuate aging-related decline in physical function. New & NoteworthyWe show evidence that combining Tat-Beclin1 and endurance training (TB+Exe) resulted in greater improvements in physical function in 24-month-old male mice than either standalone therapy. We also show that TB+Exe upregulates traditional exercise-like biological processes and unexpectedly upregulates acute-inflammatory proteins (e.g., orosomucoid-1), which are thought to improve physical function in preclinical studies. Our study suggests that TB may be a new drug enhancing physical function, especially when combined with endurance training in old male mice.

Sensory degradation with aging can impair balance control, partly by disrupting visual contributions to self-motion estimation. We investigated how aging affects the control of frontal plane center of mass (CoM) trajectories during walking with exposure to repeated visual perturbations. We hypothesized that aging would increase responses to visual perturbations and decrease adaptation to repeated visual perturbation exposure. We applied three visual perturbations to 14 healthy older (age: 75.0{+/-}2.4) and 16 younger adults (age: 23.4{+/-}3.9) walking on a treadmill: fixating a stationary target with the background moving to the right (MB), tracking a target moving rightward over a stationary background with head rotation (MT-HR), and tracking a moving target with eye movement only (MT-EM). Deviations of CoM position and foot placement due to the visual perturbations were assessed. Over the whole trial, the older adults exhibited larger CoM position variability in MB and MT-HR conditions. During visual perturbation epochs, both age groups deviated in the same direction except MB. In MB, the older adults deviated to an opposite direction after a few perturbation repetitions. Moreover, in MT-HR and MT-EM, the older adults deviated earlier than the younger adults and they deviated more in the MT-HR condition. This indicates that older adults exhibit reduced ability to accurately estimate self-motion through correction by other sensory modalities when exposed to visual perturbations. Over repeated perturbations, the older adults showed decreased CoM deviations in MT-EM, which suggests that they still maintain the capacity to downweight visual information after repeated exposure.