npj aging最新文献

The central nervous system, comprised of the brain, spinal cord, and nerves, includes the autonomic nervous system (ANS) that regulates involuntary functions. Within the ANS, the sympathetic and the parasympathetic nervous systems (SNS and PNS, respectively) control the same bodily functions, but in opposing directions. For example, the sympathetic nervous system elicits our "fight or flight" response, while the parasympathetic system supports "rest and repair" mechanisms in the broadest possible sense. With age, changes occur in how information is transmitted, in energetic requirements and expenditures, and in the ability to respond to change. These alterations with age result in the "hallmarks of aging", specifically including genomic instability, telomere attrition, epigenetic changes, loss of proteostasis, deregulated nutrient-sensing, mitochondrial dysfunction, cellular senescence, stem cell exhaustion, and chronic inflammation. Understanding these age-dependent changes is essential for promoting healthy aging and longevity. We propose that, at the core of aging, there is an imbalance between the SNS and PNS, which provides opportunities for therapeutic intervention.

Senescent cells, characterized by a state of irreversible proliferative arrest and inflammatory profile, have emerged as drivers of age-related decline. Growing evidence suggests that alterations in mitochondrial function and morphology play a key role in the induction and maintenance of senescence, as well as in promotion of the proinflammatory senescence-associated secretory phenotype (SASP). In this review, we seek to survey the relationship between mitochondrial dysfunction and senescence, focusing on the consequences of changes in oxidative phosphorylation efficiency, calcium handling, mitochondrial metabolites, mitochondrial dynamics and quality control, and release of damage-associated molecular patterns. We first describe these changes before illustrating the pathways and mechanisms through which mitochondrial dysfunction results in cell cycle arrest and the SASP. Lastly, we showcase evidence relating cellular senescence to neurodegenerative disease and propose that mitochondrial dysfunction may act as a bridge between the two.

We aimed to develop and validate a urinary miRNA aging clock, positioning urine as a scalable, non-invasive aging-biomarker source. Using machine learning on 6331 adults, our clock achieved MAE ≈ 4.4 years (R² ≈ 0.79) in independent validation. The clock's key biomarkers included well-established geromiRs miR-34a-5p, miR-31-5p, miR-146a-5p, and miR-155-5p. While slightly less accurate than DNA-methylation clocks, our model outperformed blood-based miRNA and mRNA clocks, underscoring urinary miRNAs as promising, truly non-invasive biomarkers of biological age and disease risk.

Multimorbidity elevates late-life mortality, yet existing tools remain complex. Using two nationally representative Chinese cohorts-the Chinese Longitudinal Healthy Longevity and Happiness Family Study (CLHLS-HF; n = 8675) and the China Health and Retirement Longitudinal Study (CHARLS, n = 4171)-we developed and externally validated a simplified, time-dependent, interpretable survival model. A four-stage feature-selection pipeline (univariate Cox, L1-penalized Cox, multi-model importance with 100 bootstraps, and cumulative performance) identified four routinely available predictors: age, BMI, and cooking and toileting abilities. Among five algorithms, a parsimonious Cox model performed best (C-index 0.7524 internal; 0.7104 external) with a favorable time-Brier Score (0.1417; 0.1157), good calibration, decision-curve net benefit, and subgroup fairness. Time-dependent permutation importance confirmed age as dominant, toileting ability as short-term, and cooking ability as mid- to long-term contributors, while BMI showed modest, stable effects. Implemented as the M-SAGE online tool, this four-item model enables rapid, interpretable mortality risk stratification and supports individualized interventions for older adults with multimorbidity.

As aging is the primary risk factor for many chronic diseases, geroscience aims to target aging to delay age-related decline. Here, we identify Cyrene (dihydrolevoglucosenone), a sustainable, biocompatible solvent, as a novel geroprotective compound. Cyrene extends lifespan and healthspan in C. elegans, improving locomotor function and resistance to oxidative, thermal, osmotic, genotoxic, and proteotoxic stress. It also confers protection in neurodegenerative models of Alzheimer's, Parkinson's, and Huntington's disease. Cyrene is effective when delivered during development or early adulthood and requires administration before day 8 to extend longevity. Its benefits are independent of bacterial metabolism and at least partially independent of the FOXO transcription factor DAF-16. Importantly, Cyrene also extends lifespan and enhances oxidative stress resistance in Drosophila melanogaster, demonstrating cross-species efficacy. These findings identify Cyrene as a novel geroprotective compound that promotes longevity, resilience, and neuroprotection. Conservation across species supports future work to dissect molecular mechanisms and test its potential in mammals.

Skin is both the most visible and most environmentally exposed organ, with apparent aging phenotypes. DNA methylation clocks faithfully capture the progression of aging, but so far have been limited to training on abundant in vitro material or invasively collected samples to generate narrow methylomes using microarray platforms. Here, we demonstrate that skin biological age can be measured directly from a person's face with superior accuracy, using non-invasive tape-stripping. We developed two clocks, MitraSolo, based on single CpGs, and MitraCluster, on regions, trained on the largest enzymatic methyl-sequencing dataset of human epidermis (n = 462). Our models were validated on independent, longitudinal, and external datasets and were compared against established clocks. They predict age accurately, with an error of approximately 4 years, outperforming others on epidermal samples. They maintain high accuracy at low sequencing depths, enabling cost-effective scalability and show intra-individual prediction variation <2 years, highlighting their reproducibility. Their predictive capacity generalised across anatomical sites, conversion and sampling methodologies and on in vitro material. They also successfully captured the rejuvenating effects of Yamanaka factor treatment. MitraSolo and MitraCluster represent a new class of epigenetic clocks optimised for human skin with characteristics that support their use in clinical research, intervention monitoring, and skincare innovation.

The EAT-Lancet diet has been recently recommended for its potential health and environmental benefits. Here, leveraging data from the UK Biobank, we performed a comparative analysis to examine the associations of adherence to the EAT-Lancet diet versus traditional plant-based diets with biological aging and further assess the mediating role of metabolomic signatures specific to dietary patterns. Compared with the overall or healthful plant-based diet index, higher adherence to the EAT-Lancet diet was more strongly associated with decreased KDM-BA and PhenoAge acceleration and increased telomere length. In contrast, a higher unhealthful plant-based diet index was associated with accelerated biological aging. We identified substantial metabolomic variation in relation to different dietary patterns. The diet-specific metabolomic signatures mediated 26.9-63.0% of the associations between dietary patterns and biological aging. Our findings suggest the potential benefits of adopting the EAT-Lancet and plant-based diets in promoting healthy aging and highlight the potential of metabolomic signatures for informing personalized nutrition interventions.

Fatty acids are involved in disease risk and aging processes. In the US National Health and Nutrition Examination Survey (1999-2002), we tested for associations of total, saturated (SFA), monounsaturated (MUFA), polyunsaturated (PUFA), and subtypes of dietary fatty acids with DNA methylation-based aging biomarkers, adjusting for age, BMI, total energy intake, and sociodemographic and behavioral factors (N = 2260). Higher SFA and MUFA were associated with greater GrimAge2, an aging biomarker of mortality; PUFA was associated with lower Horvath1, Hannum, and PhenoAge (p < 0.05). Omega-3 and the PUFA:SFA ratio were negatively associated with Horvath1, Hannum, Vidal-Bralo, and PhenoAge. Notably, a one-unit increase in PUFA:SFA was associated with 1.05 years lower PhenoAge (95% CI = -1.87, -0.22). We found consistent positive associations for SFA subtypes and negative associations for PUFA subtypes with epigenetic aging; associations of MUFA subtypes varied. Future studies, including randomized controlled trials, are needed to investigate causality and downstream clinical outcomes.

Auditory gamma stimulation is a promising non-invasive neuromodulation technique for cognitive decline, with preclinical studies demonstrating therapeutic effects in Alzheimer's disease models. However, translating these findings into human trials has produced variable outcomes, suggesting a need to examine factors influencing efficacy. In a systematic review of 62 studies on healthy and cognitively impaired populations, we identified 16 characteristics that may affect the response to stimulation. Outcomes reported included improved cognition, slower progression of brain atrophy, and changes in functional connectivity. Optimal stimulation frequency varied across individuals, indicating that personalised approaches may be valuable. Importantly, animal-model findings regarding amyloid clearance and reduced neuroinflammation were not consistently replicated in human studies, nor did neurophysiological responses reliably predict cognitive or biological effects. Significant methodological diversity was evident, with 32 neurophysiological measures employed, highlighting a need for standardisation. Future research should prioritise consensus on outcome measurement and explore individualised intervention strategies to better assess therapeutic potential.

Brain aging is a major factor in cognitive decline and Alzheimer's disease (AD) progression. Aging-induced microglial senescence critically drives inflammaging and brain aging processes. Nevertheless, the underlying reasons and mechanisms that promote microglial aging remain unclear. This study explores how 27-hydroxycholesterol (27-OHC), a key oxysterol, accelerates brain aging by promoting microglial senescence, iron overload, and neuroinflammation. Clinically, we observed a significant inverse correlation between plasma 27-OHC levels and Mini-Mental State Examination (MMSE) scores in AD patients, accompanied by reduced 24S-OHC concentrations. Experimental studies revealed that 27-OHC administration in mice induced hippocampal-dependent cognitive impairment and anxiety-like behaviors, concurrent with elevated expression of cellular senescence markers (P21, P16, SA-β-Gal) and M1 microglial polarization. In BV-2 cells, 27-OHC disrupted iron homeostasis (DMT1/ferritin/GPX4 dysregulation), elevating ROS and impairing mitochondrial function. Deferoxamine (DFX) mitigated microglial senescence and ferroptosis. These findings establish the 27-OHC-iron axis as a novel therapeutic target for combating cholesterol-driven neurodegeneration.