Longevity Papers

Epigenetic clocks can predict biological age but cannot prescribe the interventions needed to reverse it. Here, we introduce REjuVenatIon Via Epigenetic Flow (REVIVE-Flow), a flow-matching model trained on a broad compendium of epigenetic blood studies to transport methylomes forward and backward in time. First, we learn the continuous vector field of aging as an Ordinary Differential Equation (ODE) within a stable, low-dimensional linear space. Then, the learned ODE\'s dynamics are integrated backward in time to define a natural, biologically-plausible rejuvenation trajectory. This path serves as a guide for a convex optimization problem that identifies the minimal, targeted CpG-level perturbation required to rejuvenate a sample. On a completely unseen test set comprising over 800 individuals from the European Prospective Investigation into Cancer and Nutrition (EPIC-Italy) cohort, Revive achieves 0.4 years rejuvenated per commanded year (R2=0.99), with a smooth sparsity-effect trade-off. Extensive validation confirms the effect preserves inferred cell-type composition and targets biologically plausible loci enriched in genomic regions and pathways central to aging biology.

Inorganic pyrophosphate (PPi) is a critical inhibitor of ectopic calcification, yet transcriptional regulation of genes controlling its systemic production and degradation (ABCC6, ALPL, ANKH, ENPP1) remains elusive. We hypothesized that PPi homeostasis is governed by evolutionarily conserved transcription factor (TF) network. Promoter-motif analysis of PPi genes revealed conserved enrichment of nuclear receptor TFs (ESR1, NR4A1, RXRA, NR1H3/LXR) and metabolic regulators (SREBF1, CEBPB, HNF4A) across mouse and human orthologues. Supporting this, analysis of public RNA-seq datasets and RT-qPCR in wild-type and Abcc6-/- mice demonstrated tight co-expression of these genes in the liver and the kidney, as central transcriptional hub of systemic PPi regulation. Functionally, analyses in mice revealed age-dependent inverse coupling between plasma PPi concentration and serum alkaline phosphatase (AP) activity, with strongest impact during early life. Abcc6-/- mice exhibited persistently reduced although gradually increasing PPi and altered Pi/PPi ratios during aging. Translating these findings to humans, plasma PPi correlated inversely with AP activity and positively with Pi, though associations were weaker in ABCC6-deficient pseudoxanthoma elasticum patients. These results establish a conserved TF-driven program coordinating hepatic and renal expression of PPi homeostatic genes, highlight early-life sensitivity of PPi balance, and link gene-regulation to circulating mineralization factors, highlighting species-specific and pathology-driven differences.

Biological regulation is a highly intricate process and involves many layers of complexity even at the RNA level. Alternative splicing is crucial in the regulation of which components of a protein-coding gene are spliced into a translatable mRNA. During ageing splicing becomes dysregulated and alternative splicing has been shown to be involved in disease and known anti-aging treatments such as dietary restriction (DR) and mTOR suppression. In prior work we have shown that DR and mTOR suppression modulate the expression of the spliceosome in the fly (Drosophila melanogaster). Here, we manipulated the five top genes that change in expression in both these treatments. We found that knockdown (using conditional in vivo RNAi in adults) of some spliceosome components rapidly induce mortality, whereas one, Rbp1, extends lifespan. Treatments that have more instant benefits on longevity are more translatable. We therefore subsequently repeated the Rbp1 experiment, but initiating Rbp1 at later stages in adult life. We find that irrespective of age of induction, knockdown of Rbp1 extends lifespan. Our results posit the spliceosome itself as a hub of regulation that when targeted can extend lifespan, rendering it a promising target for geroscience.

Anabolic and catabolic processes are coordinated by a conserved regulatory network, which includes the nutrient sensing protein kinase mTOR complex 1 (mTORC1) and the insulin- and stress-responsive transcription factor FoxO. In physiological setting these regulators align growth, storage, reproduction, and aging with nutrient availability. Here, we identify transcription factor Spalt-related (Salr), previously implicated in organogenesis, as a negative regulator of growth and lipid storage. In the Drosophila fat body Salr activates catabolic gene expression and restricts mTORC1-mediated cell growth. The genomic binding of Salr overlaps extensively with that of FoxO and similar convergence is observed between their mammalian homologs SALL1 and FOXO1. Both Salr and FoxO are activated upon fasting but respond to distinct cues: while FoxO displays transient activation and is responsive to AKT inhibition, Salr is activated in a slow and sustained manner through the integrated stress response. Once activated, Salr counters nuclear localization of FoxO. Together, Salr and FoxO are converging transcriptional activators of catabolism during nutrient stress.

Pulmonary Fibrosis (PF) is a life-threatening illness that is characterized by progressive scarring in the lung interstitium. There is an urgent need for new PF therapies because current treatments only slow down the progression of fibrosis, and the median life expectancy post-diagnosis is only 4-6 years. Since PF patients frequently exhibit telomere attrition, overexpressing telomerase, the enzyme responsible for synthesizing telomeres, represents a compelling therapeutic option. In this study, we in vitro transcribed human telomerase reverse transcriptase (hTERT) mRNA using modified nucleosides (modRNA). ModRNA hTERT treatment led to transient activation of telomerase activity in a dose-dependent manner in MRC-5 cells and, importantly, in primary human alveolar type II pneumocytes. Consequently, the proliferative capacity was increased, concomitant with reduced DNA damage and elongated telomere length. Notably, the induction of cellular immune response was only detectable at the highest modRNA concentration and returned to normal levels within 48 h. Next, we demonstrated that circularized, exonuclease-resistant modRNA hTERT extended the transient expression profile, which may be clinically advantageous. Finally, we provided therapeutic proof of concept in organotypic 3D ex vivo human precision-cut lung slices derived from end-stage PF patients. Intriguingly, a single modRNA hTERT treatment inhibited senescence, as indicated by significantly lower levels of senescence-associated β-galactosidase. Pro-inflammatory markers (IL6 and IL8) and, concurrently, the key fibrosis mediators TGFβ and COL1A1 were markedly reduced after modRNA and circular RNA hTERT treatment. In conclusion, the data presented herein provide initial evidence for the potential of RNA-based hTERT therapy for treating human lung fibrosis.

Calorie restriction (CR) is the reduction in calorie intake while avoiding malnutrition. CR increases longevity and attenuates the development of many age-related diseases, although some unfavourable responses have been reported. In response to CR, energy is withdrawn from tissues to correct the energy deficit. Changes in tissue mass over short-term, 3 months graded CR (STCR) were complex and while most tissues reduced size, some grew. Employing a graded long-term CR (LTCR) protocol in male C57BL/6J mice, tissue utilisation, digestive efficiency, bone health and motor coordination was investigated. Mice were restricted by 10-40% over 580 days/19 months and sacrificed at 24 months old. Control mice fed ad libitum in the 12hr darkphase only (12AL) were regarded as 0CR. The patterns of tissue weights, digestive efficiency, and bone measurements across the levels of CR were consistent between the STCR and LTCR studies, highlighting shared similarities over both experiments. Notable differences were enhanced utilisation of the reproductive accessory organs which could be linked to a shutdown of the reproductive axis; reduced utilisation of the spleen, changes in the hierarchy of investment in the digestive organs which was not linked to digestive efficiency. The vital organs were protected from utilisation, with preservation of the brain by CR, presumably linked to reduced neurodegeneration and sustained coordination. The favourable effects of LTCR on bone health contradict previous negative reports. Overall, morphological changes determined within 3 months of CR, persisted to 19 months. The pattern of tissue utilisation may be critical to the beneficial effects of CR.

The progressive functional decline associated with aging is a primary risk factor for numerous chronic diseases. The discovery of natural compounds that can modulate conserved longevity pathways offers a promising strategy for promoting healthy aging. Hyperoside, a flavonoid abundant in edible plants such as hawthorn, possesses various pharmacological activities, but its specific role and molecular mechanisms in geroprotection remain poorly understood. This study aimed to elucidate the anti-aging effects of hyperoside and its underlying mechanisms using the model organism Caenorhabditis elegans (C. elegans). Our results showed that hyperoside treatment significantly extended the mean lifespan of wild-type C. elegans by up to 19.97% and robustly enhanced healthspan by improving motility and reducing the accumulation of the aging biomarker lipofuscin. Hyperoside could also alleviate Parkinsonism in neurodegeneration models, without disrupting lipid homeostasis or reproduction. Furthermore, hyperoside conferred increased resistance to thermal, oxidative, and pathogenic stress. Mechanistically, the lifespan-extending effects of hyperoside requires the transcription factors DAF-16/FOXO, SKN-1/Nrf2, and HSF-1, and factors involved in immune and anti-oxidative response, including the MAPKK SEK-1 and p38 MAPK PMK-1. Hyperoside treatment promoted the nuclear translocation of DAF-16 and SKN-1 and upregulated their respective downstream target genes, including sod-3 and gst-4. Hyperoside also increased the expression of genes that are the downstream target of both PMK-1 and SKN-1. Since the role of SKN-1 in immune and anti-oxidative response were regulated by PMK-1. Therefore, the beneficial effects of hyperoside might be mediated primarily by activating SEK-1 /PMK-1/ SKN-1 pathway, which subsequently activate HSF-1 to maintain proteostasis. These findings underscore the potential of hyperoside as a dietary-derived agent for combating age-related functional decline.

Ion transport within mitochondria influences their structure, energy production, and cell death regulation. TMBIM5, a conserved calcium/proton exchanger in the inner mitochondrial membrane, contributes to mitochondrial structure, ATP synthesis, and apoptosis regulation. The relationship of TMBIM5 with the mitochondrial calcium uniporter complex formed by MCU, MICU1-3, and EMRE remains undefined. We generated Tmbim5-deficient Drosophila that exhibit disrupted cristae architecture, premature mitochondrial permeability transition pore opening, reduced calcium uptake, and mitochondrial swelling - resulting in impaired mobility and shortened lifespan. Crossing these with flies lacking mitochondrial calcium uniporter complex proteins was generally detrimental, but partial MICU1 depletion ameliorated the Tmbim5-deficiency phenotype. In human cells, MICU1 rescues morphological defects in TMBIM5-knockout mitochondria, while TMBIM5 overexpression exacerbates size reduction in MICU1-knockout mitochondria. Both proteins demonstrated opposing effects on submitochondrial localization and coexisted in the same macromolecular complex. Our findings establish a functional interplay between TMBIM5 and MICU1 in maintaining mitochondrial integrity, with implications for understanding calcium homeostasis mechanisms.

Finite replicative potential is a defining feature of non-transformed somatic cells, first established by Leonard Hayflick in vitro using WI-38 human lung fibroblasts. Once proliferative capacity is exhausted due to telomere shortening, cells enter into a state called replicative senescence, which can be avoided through ectopic expression of telomerase reverse transcriptase (hTERT). As WI-38 cells approach replicative arrest, molecular pathways linked to mechanotransduction are induced, including YAP signaling, but the potential interplay between replicative lifespan and the mechanical environment of the cell remains unexplored. Here, we investigate the influence of mechanosensation on the trajectory towards replicative arrest taken by WI-38 cells by growing cells on substrates of varying stiffnesses. Matrix softening slowed proliferation, altered cellular phenotypes, and shortened proliferative lifespan while hTERT expression abrogated or reduced these responses. Our analyses of bulk and single-cell RNA-sequencing and ATAC-sequencing revealed the emergence of a unique G1 transcriptional state on soft substrates, characterized by an AP-1 transcription factor program, which failed to manifest with hTERT expression. Together, these findings reveal how the mechanical environment alters WI-38 cell proliferative lifespan and dictates unique paths towards growth arrest.

The transcription factor CCAAT/enhancer binding protein alpha (C/EBPα) regulates cell differentiation, proliferation, and function in various tissues, including the liver, adipose tissue, skin, lung, and hematopoietic system. Studies in rats, mice, humans, and chickens have shown that CEBPA mRNA undergoes alternative translation initiation, producing three C/EBPα isoforms. Two of these isoforms act as full-length transcription factors with N-terminal transactivation domains and a C-terminal dimerization and DNA-binding domain. The third isoform is an N-terminally truncated variant, translated from a downstream AUG codon. It competes with full-length isoforms for DNA binding, thereby antagonizing their activity. Expression of the truncated C/EBPα isoform depends on the initial translation of a short upstream open reading frame (uORF) in the CEBPA mRNA and subsequent re-initiation at a downstream AUG codon, a process stimulated by mTORC1 signaling. We investigated whether the ortholog of the CEBPA gene in the evolutionarily distant, short-lived African turquoise killifish (Nothobranchius furzeri) is regulated by similar mechanisms. Our findings reveal that the uORF-mediated regulation of C/EBPα isoform expression is conserved in killifish. Disruption of the uORF selectively eliminates the truncated isoform, leading to unrestrained activity of the full-length C/EBPα isoforms. This genetic modification significantly extended both the median and maximum lifespan and improved the healthspan of male N. furzeri. Furthermore, comparative transcriptome analysis revealed an upregulation of genes and pathways that are associated with healthspan and lifespan regulation in other species. These results highlight a conserved mechanism of CEBPA gene regulation across species and its potential role in modulating the lifespan and aging phenotypes.

The mechanisms of aging are becoming increasingly well mapped; however, there remains ongoing debate about the ultimate and proximate causes of aging. The recent development of highly precise aging clocks led to a resurgence of arguments in support of a biological program of aging. However, the declining force of natural selection after the onset of reproduction means that cellular function could deteriorate without requiring a specific program. Here, we argue that aging clocks do not imply an intrinsic program but rather reflect the stochastic accumulation of molecular errors and damage. Damage accumulates due to insufficient maintenance and repair and contributes to system-wide entropy. In support of this, cross-species comparisons indicate that enhanced DNA repair capacity is a key determinant of exceptional longevity in mammals. By better understanding the nature of the stochasticity that governs the aging process, we will have a stronger mechanistic basis for developing geroprotective interventions to promote healthy aging in humans.

Background: The hippocampus undergoes extensive cellular remodelling throughout life in response to multiple biological factors that shape its structure and function. Aging represents a fundamental driver of brain changes, with the hippocampus being particularly vulnerable to age-related concerns that contribute to cognitive decline and neurodegenerative disease risk. Reproductive experience, including pregnancy and motherhood, triggers profound hormonal fluctuations and metabolic demands that are increasingly recognized as major modulators of brain plasticity, yet represent an understudied and often paradoxical dimension of neurobiological variation. Although reproductive experience and aging are each known to influence biology across the dorsal and ventral hippocampus, their independent and interactive effects on cellular composition have not been systematically examined using quantitative approaches that can resolve cell-type-specific changes. Methods: We performed cell type deconvolution using Single-cell deconvolution of cell types (SCDC) on bulk RNA-sequencing data from female rat hippocampus, comparing nulliparous and parous females across young/older ages (7 month or 13 month old Sprague-Dawley rats, parous: 30 days or 6 months after giving birth) and dorsal/ventral regions. We harmonized 201 cell type annotations from three single-cell reference datasets into 23 biologically coherent categories utilizing female only data. Three-way ANOVA was used to identify independent and interactive effects. Complementary analyses (random forest, PCA, DESeq2) identified parity-associated transcriptional signatures. Cell-specific functional enrichment was performed by weighted gene set enrichment meta-analysis across multiple pathway databases and metrics. Results: Age emerged as the dominant factor affecting hippocampal cellular composition, significantly altering 6 harmonized cell types, particularly impacting microglia and oligodendrocytes. Regional effects were more extensive, affecting 9 harmonized cell types, while age x region interactions were minimal affecting two harmonized cell types. Critically, parity exerted independent effects on three cell populations: dorsal CA3 pyramidal neurons (p=0.0086-0.010 across two datasets) and SST interneurons (p=0.029) both showed 15-25% decreases, while astrocytes increased (p=0.022). Cell-type-specific pathway analysis revealed distinct molecular mechanisms with enrichment for protein degradation pathways in CA3 pyramidal neurons (GSK3B and BTRC:CUL1-mediated degradation; ubiquitin-dependent degradation of Cyclin D), neuroinflammation pathways in astrocytes, and GABAergic signaling disruption in SST interneurons (signaling receptor activity; GPCR ligand binding). Conclusions: Reproductive experience selectively remodels hippocampal cellular architecture through distinct, cell-type-specific molecular programs that operate independently of age and regional factors. These findings show parity as a critical biological variable requiring consideration in neuroscience and aging research and suggest specific cellular targets for understanding how reproductive history influences brain function.

As the global population ages, the prevalence of cognitive decline is rising, creating urgent demand for proactive strategies that support brain health and healthy aging. Ergothioneine, a unique dietary amino-thione absorbed via the OCTN1 transporter, has recently gained attention for its potential as a neuroprotective, longevity-promoting compound. This review synthesizes growing evidence from observational, interventional, and mechanistic studies. Observational data consistently associate low blood ergothioneine levels with cognitive impairment, neurodegenerative diseases, cardiovascular disorders, frailty, and mortality. Interventional trials in older adults suggest that ergothioneine supplementation may improve cognition, memory, sleep quality, and stabilize neurodegeneration biomarkers, with no safety concerns at doses up to 25 mg/day. Mechanistic studies reveal that ergothioneine acts through multiple pathways: mitigating oxidative stress, reducing neuroinflammation, preserving mitochondrial function, and potentially modulating neurogenesis and NAD⁺ metabolism, although some mechanisms require further investigation. Beyond cognition, ergothioneine shows promise in supporting other physiological systems relevant to aging, including cardiovascular, metabolic, gut, eye, auditory, liver, kidney, immune, skin, and lung health. Together, current evidence positions ergothioneine as a promising nutritional intervention for promoting cognitive resilience and systemic health in aging, although larger, long-term interventional trials are needed to confirm causality and optimize use.

Ageing is a general, intrinsic and progressively deleterious process that affects all cells, tissues and organs albeit at different extent and rate in each individual. The complexity and universality of its phenotypic manifestations suggest a multifactorial origin. The autosomal recessive disorder Werner syndrome likely represents a segmental progeroid disorder since patients show several, but not all phenotypes of premature ageing.

Parkinson's disease is a neurodegenerative disorder of aging with dopaminergic neuronal degeneration in the substantia nigra leading to motor dysfunction. Mitochondrial dysfunction is central to its pathophysiology, leading to oxidative stress, derangement of energy metabolism, and induction of neuronal apoptosis. Current therapeutic interventions are symptomatic but fail to stop disease progression. Stem cell-based regenerative strategies have been recognized as potential disease-modifying treatments. Mitochondria-augmented stem cell therapy offers a new mechanism for the correction of cellular bioenergetic deficits. Through genetic manipulations or preconditioning protocols, mesenchymal stem cells and induced pluripotent stem cells are engineered to enhance mitochondrial function and transfer. The engineered cells enable delivery of functional mitochondria into damaged neurons through tunneling nanotubes or extracellular vesicles, promoting ATP production, inhibiting reactive oxygen species, and restoring mitophagy. Preclinical models have demonstrated improved neuronal survival and motor function, and novel technologies like CRISPR gene editing and 3D bioprinting offer improved translational relevance.

The DREAM complex has emerged as a central repressor of DNA repair, raising questions as to whether such repression exerts long-term effects on human health. Here we establish that DREAM activity significantly impacts lifetime somatic mutation burden, and that such effects are linked to altered lifespan and age-related disease pathology. First, joint profiling of DREAM activity and somatic mutations across a single-cell atlas of 21 mouse tissues shows that cellular niches with lower DREAM activity have decreased mutation rates. Second, DREAM activity predicts the varied lifespans observed across 92 mammals, with low activity marking longer-lived species. Third, reduced DREAM activity in Alzheimer\'s patients predicts late disease onset and decreased risk for severe neuropathology. Finally, we show DREAM knockout protects against mutation accumulation in vivo, reducing single-base substitutions by 4.2% and insertion/deletions by 19.6% in brains of mice. These findings position DREAM as a key regulator of aging.

Physiological aging is accompanied by structural and molecular changes in the brain, with varying degrees in different brain areas, and is considered one of the major risk factors for neurodegenerative diseases. Thus, the present study focuses on elucidating age-related changes in the substantia nigra pars compacta (SNpc), a brain region particularly vulnerable in Parkinson's disease. Here, the aim is to gain a spatially resolved view of aging-dependent alterations to conclude early processes potentially involved in neurodegeneration. Neuromelanin granules and SNpc tissue are isolated from tissue samples of young and elderly individuals via laser microdissection and measured by mass spectrometry to ascertain changes in protein expression in response to age. The findings include the identification of reduced levels of proteins involved in dopaminergic neurotransmission, either suggesting a specific loss of dopaminergic neurons or a reduction in metabolic activity. Furthermore, increased neuroinflammation is observed in elderly individuals and alterations in vesicular trafficking as well as mitochondrial proteins. Consequently, this exploratory study suggests that alterations causing known pathomechanisms of Parkinson's disease are already occurring in the physiological aging process. Since aging is still the most important risk factor for neurodegenerative diseases, these findings strengthen the necessity for studying age-related changes.

Pulmonary hypertension (PH) is a life-threatening disease increasingly being diagnosed in the elderly population, marked by vascular injury, excessive vasoconstriction and progressive remodelling of the pulmonary arteries (PAs). These lead to sustained elevation of PA pressure and subsequent development of right ventricular failure. Despite the beneficial effects on disease progression and quality of life, current treatments do not cure PH, highlighting the need for a deeper understanding of the underlying mechanisms. Recently, cellular senescence has gained much attention as a stress response programme with substantial and somewhat controversial implications for both functional and structural changes within the pulmonary vasculature. Herein, we provide updated insights into the complex role and duelling good and bad effects of senescent cells in the development and progression of PH and discuss the novel therapeutic avenues that this connection opens. Finally, we identify challenges and unmet needs in understanding the two-faced nature of cellular senescence in PH and leveraging senescence therapeutically.

Biological aging, measured using DNA methylation, is a potential biomarker for cognitive health outcomes. We evaluated associations between DNA methylation measures of aging and cognition in a nationally representative sample of adults aged 60+ in the National Health and Nutrition Examination Survey (NHANES), 1999-2002. Genome-wide DNA methylation data were used to create 13 measures of biological aging trained on different aging phenotypes. Cognition was assessed with the Digit Symbol Substitution Test (DSST). To evaluate associations between each DNA methylation measure and DSST score, survey-weighted linear regression models adjusted for age, sex, race/ethnicity, education, smoking, serum cotinine, and BMI were run. We assessed effect modification by sex, education, and race and ethnicity. Included participants (N=1,463) were an average of 70.5 years old and 82.7% non-Hispanic White. The average DSST score was 46.9 (SD 17.6). Ten of 13 DNA methylation measures were associated with DSST (adjusted p<0.05). One year of GrimAge2 accelerated aging was associated with -0.41 points lower DSST score (95% CI: -0.61, -0.21; adjusted p=5x10-4). In stratified analyses, higher magnitudes of association were observed among male and non-Hispanic White participants across multiple aging measures. DNA methylation may be a useful biomarker of cognitive status among older adults.

Calcification of the aortic valve is a prevalent cardiovascular pathology in the aging population. Traditionally linked to inflammation, lipid accumulation, and risk conditions, this disease remains poorly understood, and effective treatments to halt its progression are not yet available. We hypothesized that calcification of the human valve interstitial cells (VICs) is associated with cellular senescence and alterations in the epigenetic setup, like in arteries. To verify this hypothesis, we examined the epigenetic marks (DNA methylation; Histones H3/H4 acetylation/methylation), the senescence and the calcification process in human VICs obtained from two distinct pathologic settings of the aortic valve (valve insufficiency and valve stenosis), and employed a mouse model of vascular/valve calcification, based on the administration of Vitamin D. Our findings revealed a link between the senescent phenotype of human VICs and calcification, characterized by increased DNA methylation and changes in histone epigenetic marks. To reverse the senescent/calcific VICs phenotype, we used Pentadecylidenemalonate-1b (SPV106), which activates KAT2B/pCAF histone acetyltransferase. In human VICs, SPV106 restored Histone acetylation marks, modified general chromatin accessibility and upregulated expression of Notch1, a potent inhibitor of valve calcification. The treatment also prevented the accumulation of calcific lesions in an ex vivo model of aortic valve calcification. In vivo treatment with SPV106 reduced calcification of the valve induced by administering Vitamin-D and positively preserved the valve motion compromised by calcification and the overall cardiac function. Based on these results, we propose the treatment with activators of histone acetylates as a viable option to prevent senescence/calcification of aortic VICs via restoration of correct chromatin acetylation, with concrete hopes to retard the progression of valve stenosis, a still largely unmet therapeutic need.

Loss of epigenetic information has been proposed as a potential driver of mammalian aging. However, its contribution to the well-documented variation in lifespan estimates among mammals remains to be elucidated. In this study, we examined DNA methylation entropy patterns at evolutionarily conserved CpG sites across multiple mammalian species to quantify age-associated epigenetic information loss. We found that longer-lived species tend to accumulate fewer CpGs exhibiting increased methylation noise over time, irrespective of whether these changes arise from hyper- or hypomethylation mechanisms. Importantly, the rate of epigenetic entropy gain declines in a linear fashion with species' maximum lifespan, pointing to the existence of a universal constraint on mammalian longevity, estimated to lie in the vicinity of 220 years. We further demonstrated that this relationship and its associated limit were independent of species and sample selection, as well as phylogenetic relatedness, and remained robust across different scenarios of lifespan estimation uncertainty. Collectively, this work highlights the maintenance of epigenetic information as a key factor in explaining lifespan differences among species and proposes a universal maximum limit to natural mammalian longevity.

Aging disrupts brain network integration and is a significant risk factor for cognitive decline and neurological diseases, yet the circuit-level mechanisms underlying these changes remain unclear. Most previous studies have utilized cross-sectional or acute approaches, limiting insights into the longitudinal dynamics of the neural network. In this study, we chronically recorded laminar electrophysiological activity in both the primary visual cortex (V1) and hippocampal CA1 region of young (2-month-old) and aged (13-month-old) mice over 16 weeks. This approach allowed us to directly assess how aging modulates functional connectivity within hierarchically connected cortical and hippocampal circuits. We found that single-unit spiking activity and the signal-to-noise ratio were largely preserved in aged versus young mice, suggesting intact neuronal firing properties. However, aged mice showed global reductions in local field potential (LFP) power and a selective decrease in coherence across delta, alpha-beta, and gamma frequency bands within and between cortical layers and V1-CA1 pathways, while phase amplitude coupling remained unaffected. Interestingly, population level excitatory activity in CA1 was increased in aged animals. These findings indicate that aging selectively impairs network-level synchrony and temporal coordination in specific frequency bands and regions, with minimal loss of single-neuron function. Our results highlight the necessity of longitudinal, multi-region measurements to uncover the multi-scale vulnerabilities of the aging brain. Understanding the depth- and region-dependent circuit changes will guide strategies to preserve cortical-hippocampal communication and cognitive function in aging, as well as enhance neural interface technologies for older populations.

Changes in synaptic integrity and neural activity homeostasis are hallmarks of brain aging and are closely tied to cognitive outcomes. Yet, defining their relationship across the continuum from normal aging to neurodegenerative disease has proven challenging. Recent research investigating the dynamic changes of neuronal pentraxin 2 (NPTX2, or Narp, neuronal activity-related pentraxin) in cerebrospinal fluid (CSF) of Alzheimer\'s disease (AD) subjects supports its promise as a prognostic marker of disease progression, possibly as an expression of synaptic damage related to cognitive impairment. However, studies in human subjects are unable to clearly differentiate age-related and disease-related processes. Here we took advantage of a well-characterized rat model that displays substantial individual differences in hippocampal memory during aging, uncontaminated by slowly progressive, spontaneous neurodegenerative disease. Through this approach, we aimed to interrogate the underlying neural substrates that mediate aging as a uniquely permissive condition and the primary risk for neurodegeneration. We found that successful cognitive aging is associated with an elevation of NPTX2 levels above that found in young or cognitively impaired subjects. Pharmacological engagement of neural activity was sufficient to increase NPTX2 levels in all subjects, but cognitively-impaired aged subjects failed to recruit NPTX2 in response to a hippocampus-dependent memory task. Together the findings demonstrate that changes in NPTX2 are coupled to differential cognitive outcomes of aging, and that successful neurocognitive aging is associated with adaptive upregulation of NPTX2, not simply the persistence of youthful synaptic dynamics.

Aging is an inevitable, physiological process of the human body, leading to deterioration in bodily function and increased susceptibility to various diseases. Effective endogenous therapeutic strategies for anti-aging and related diseases remain limited. Exercise confers multifaceted benefits to physical health by augmenting osteogenic and myogenic processes, enhancing cardiovascular and nervous system function, and attenuating chronic inflammation. Angiogenesis and lymphangiogenesis play pivotal roles in anti-aging, tissue repair, and immune response modulation, underscoring their potential as therapeutic targets for age-related diseases. Modulating angiogenic and lymphangiogenic pathways may provide a promising strategy for mitigating vascular decline and immune system dysfunction associated with aging. Exercise-induced endogenous angiogenesis and lymphangiogenesis can exert beneficial effects on physiological function, thereby representing a potential therapeutic paradigm for combating age-related decline and diseases. This review offers a thorough summary of the present knowledge regarding angiogenesis and lymphangiogenesis induced by exercise, encompassing the underlying mechanisms and the effects in different organs. In addition, it explores the potential of physical activity as a non-pharmacological intervention for anti-aging strategies and disease management, offering novel insights into the intersection of physical activity, aging, and disease progression.

Background: Sarcopenia is the progressive loss of skeletal muscle mass, strength, and function with age, driven by dysregulation in the rates of muscle protein synthesis (MPS) and breakdown (MPB). Although MPB contributes to net protein balance (NB), a primary contributor of sarcopenia is anabolic resistance, defined as the blunted MPS response to anabolic stimuli such as feeding. While candidate mechanisms of anabolic resistance have been identified, none singularly explains the reduction in MPS. Instead, multiple mechanisms likely act simultaneously and interactively to suppress MPS. Studying these interactions experimentally is challenging. Alternatively, mathematical modeling is well suited to analyzing complex biological phenomena such as anabolic resistance. Methods: We analyzed a previously developed kinetic model of leucine-mediated signaling and protein metabolism in human skeletal muscle to systematically investigate potential mechanisms contributing to anabolic resistance. A global sensitivity analysis identified key controllers of MPS, MPB, and NB. We then simulated an essential amino acid feeding intervention in older adults, classified the responses as either anabolic sensitive or resistant, and compared the resulting parameter distributions of the two groups. A targeted analysis evaluated the effects of individual and combined dysregulated putative mechanisms of anabolic resistance on muscle metabolism. Finally, we simulated therapeutic interventions aimed at restoring muscle metabolism. Results: Sensitivity analysis revealed that MPS and MPB are primarily controlled by their proximal signaling controllers, while NB is largely driven by MPS dynamics. Exploratory simulations showed that several parameters and signaling protein concentrations, particularly those controlling MPS, differed significantly between anabolic sensitive and resistant groups. Targeted simulations indicated that multiple dysregulated mechanisms were required to account for the experimentally observed reductions in MPS in older adults. Therapeutic simulations showed that while single-target interventions could largely restore MPS when isolated mechanisms were perturbed (e.g., enhancing p70S6K levels, increasing mTORC1 sensitivity), a multifactorial approach was required to recover muscle metabolism when all anabolic resistance mechanisms were present. Conclusion: This study demonstrates the multifactorial nature of anabolic resistance. We provide a framework for the experimental manipulation of independent and related factors that could underpin age-related anabolic resistance. The results motivate new hypotheses regarding the mechanisms most likely to be impaired and support the development of multi-target therapeutic strategies to help restore muscle protein metabolism in aging.

Lactate, historically considered a metabolic byproduct, has emerged as a key regulator of muscle physiology and metabolism. This study explores its potential as an exercise mimetic to counteract disuse muscle atrophy (DMA) in aging skeletal muscle using a hindlimb suspension model in senescence-accelerated prone 8 (SAMP8) mice. The mice were divided into four groups: Control, lactate-treated control, hindlimb suspension, and hindlimb suspension with lactate intervention. Lactate administration preserved gastrocnemius muscle mass, restored muscle strength, and attenuated oxidative fiber atrophy. Electrophoretic and histological analyses showed increased MyHC I expression, indicating protection of oxidative fibers. Functional assessments revealed improved muscle endurance and contractile force, while metabolomic profiling identified changes in energy metabolism, amino acid metabolism, and protein synthesis pathways. Specifically, lactate improved impaired branched-chain amino acid metabolism, suggesting enhanced protein synthesis. In addition, lactate boosted Cori cycle activity, upregulated hepatic lactate transporters, and increased lactate dehydrogenase B activity, facilitating efficient lactate metabolism and gluconeogenesis. These results provide new insights into the role of lactate as a metabolic regulator and highlight its potential as a therapeutic intervention to combat exercise-induced muscle wasting and preserve muscle function in aging and immobilized individuals.

Infra-slow (< 0.1 Hz) global brain activity, quantified by the global mean BOLD (gBOLD) signal in resting-state fMRI, is elevated during sleep and closely associated with cerebrospinal fluid (CSF) dynamics, a key mechanism for the brain waste clearance implicated in neurodegenerative disorders such as Alzheimer\'s disease (AD). However, the effect of sleep deprivation on gBOLD activity and its interaction with aging remain poorly understood. Using a rigorously controlled in-laboratory total sleep deprivation (TSD) protocol, we demonstrate that TSD significantly increases both the amplitude of the gBOLD signal and its coupling with CSF flow, suggesting a compensatory mechanism that may enhance glymphatic clearance following acute sleep loss. Notably, these TSD-induced enhancements exhibit robust age dependency, with diminished responses in individuals at midlife (40-50 yrs). The absence of this compensatory mechanism in these midlife participants may exacerbate age-related impairments in neurotoxic clearance and increase dementia susceptibility, thereby offering mechanistic insights into the nexus between sleep disruption, aging, and neurodegeneration.

The New England Centenarian Study (NECS) provides a unique resource for the study of extreme human longevity (EL). To gain insight into biological pathways related to EL, chronological age and survival, we used an untargeted serum metabolomic approach (> 1,400 metabolites) in 213 NECS participants, followed by integration of our findings with metabolomic data from four additional studies. Compared to their offspring and matched controls, EL individuals exhibited a distinct metabolic profile characterized by higher levels of primary and secondary bile acids - most notably chenodeoxycholic acid (CDCA) and lithocholic acid (LCA) - higher levels of biliverdin and bilirubin, and stable levels of selected steroids. Notably, elevated levels of both bile acids and steroids were associated with lower mortality. Several metabolites associated with age and survival were inversely associated with metabolite ratios related to NAD+ production and/or levels (tryptophan/kynurenine, cortisone/cortisol), gut bacterial metabolism (ergothioneine/ trimethylamine N-oxide, aspartate/quinolinate), and oxidative stress (methionine/methionine sulfoxide), implicating these pathways in aging and/or longevity. We further developed a metabolomic clock predictive of biological age, with age deviations significantly associated with mortality risk. Key metabolites predictive of biological aging, such as taurine and citrate, were not captured by traditional age analyses, pointing to their potential role as biomarkers for healthy aging. These results highlight metabolic pathways that may be targeted to promote metabolic resilience and healthy aging.

Intervertebral disc degeneration (IVDD) is a multifactorial pathology primarily driven by the senescence of nucleus pulposus cells (NPC), inflammatory microenvironment of extracellular matrix (ECM), and the resultant decline in NPCs viability. Conventional treatment strategies often fail to address these two interconnected factors simultaneously. To overcome this limitation, a bifunctional anti-swelling hydrogel system encapsulating anti-senescence drugs quercetin (Q) and dasatinib (D), as well as nucleus pulposus-derived exosomes (NP-Exo) is developed. This system is designed to clear senescent NPCs, regulate the inflammatory disc microenvironment, and enhance NPC activity, thereby significantly improving treatment efficacy. Mechanistically, this strategy helps preserve mitochondrial function, maintain mitochondrial membrane potential, and reduce excessive reactive oxygen species production, which collectively contribute to delaying cellular senescence and restoring disc homeostasis. Additionally, the anti-swelling property of the hydrogel can alleviate structural displacement caused by swelling, further optimizing the stability and efficacy of the treatment. The biological efficacy of this system is validated in both rat and goat models. The experimental results demonstrated that this drug delivery system can effectively restore the integrity of the ECM, ultimately promoting the repair of IVDD. These findings highlight the platform's potential for IVDD treatment, offering a novel therapeutic strategy for IVDD repair.

Despite widespread seropositivity, respiratory syncytial virus (RSV) remains a major cause of severe illness in adults aged 60 years and older. This review examines why infection-acquired immunity fails to protect this group, focusing on four key factors: structural lung decline, comorbidities, immunosenescence, and impaired antibody responses. Age-related changes weaken mechanical defenses and antiviral immunity, while chronic diseases amplify RSV risk. Critically, repeated RSV infections may preferentially boost non-neutralizing antibodies targeting the postfusion F protein, limiting protection and possibly enhancing disease. The review also highlights how newly approved vaccines, based on stabilized prefusion F protein, can overcome these barriers by inducing strong neutralizing responses, offering a targeted strategy to reduce RSV burden in older adults.

Ovarian aging is one of the common diseases in the female reproductive system. It is characterized by complex etiologies, involving multiple factors such as genetics, environment, metabolism, and cellular stress. In recent years, autophagy, a crucial cellular self-degradation and repair mechanism, has received substantial attention for its role in maintaining and deteriorating ovarian function. This review systematically summarizes the molecular mechanisms of autophagy and its regulation, as well as the latest research progress of macroautophagy, chaperone-mediated autophagy (CMA) and mitophagy in ovarian aging. Studies have shown that dysregulation of autophagic pathways is closely associated with decreased oocyte quality and reduced ovarian reserve function. Additionally, signaling pathways such as PI3K, AMPK, and mTOR participate in the process of ovarian aging by regulating autophagic activity. Although numerous studies have revealed the critical role of autophagy in ovarian aging, many issues remain to be resolved, such as the crosstalk mechanisms between different autophagic pathways and the precise spatiotemporal dynamics of the autophagic regulatory network. A deep understanding of the regulatory network of multi-pathway autophagy will provide new insights for developing intervention strategies to delay ovarian aging, holding significant scientific and clinical application value.

Epigenetic regulation is a key determinant of the aging process, and its dysregulation contributes to cognitive aging and increased vulnerability to Alzheimer's disease (AD). As major regulators of epigenetic processes, histone deacetylases (HDACs) have emerged as potential therapeutic targets for cognitive enhancement in neurodegenerative diseases. However, the distinct roles of individual HDAC isoforms remain to be defined. Here, we report that HDAC9 is specifically expressed in neurons of human and mouse brains, and its expression declines with age. HDAC9 deficiency impairs cognitive function and synaptic plasticity in young mice. Selective deletion of HDAC9 in hippocampal CA1 neurons also induces cognitive impairment. In contrast, overexpression of HDAC9 in forebrain glutamatergic neurons preserves cognitive function in aged mice. Moreover, HDAC9 is also downregulated in the brain of AD mouse models, whereas neuronal overexpression of HDAC9 alleviates AD-related cognitive and synaptic deficits and reduces A{beta} deposition. Together, these findings suggest neuronal HDAC9 is necessary and sufficient for maintaining cognitive and synaptic functions in the context of aging and AD.

Hypertension is a complex, age-related condition that markedly elevates the risk of cardiovascular problems and mortality globally. With the aging global population, understanding the molecular foundations of hypertension is essential. Emerging evidence highlights the essential roles of non-coding RNAs, particularly Long non-coding RNAs and microRNAs, in regulating gene expression linked to vascular health and blood pressure control. This review examines the impact of aging on the expression and synthesis of key ncRNAs, which leads to malfunction in three pivotal systems: vascular smooth muscle cells, the renin-angiotensin-aldosterone system, and endothelial cells. Dysregulated ncRNAs impair nitric oxide bioavailability, enhance inflammation, and modify vascular tone, resulting in arterial stiffness and increased blood pressure. Crosstalk between lncRNAs and miRNAs, as exemplified by MALAT1-miR-145 and H19-let-7b, reveals a complex regulatory network that affects vascular remodeling and homeostasis. This review highlights new molecular targets for early diagnosis and therapeutic treatment of age-related hypertension, incorporating recent findings on miRNA and lncRNA interactions.

The intestine is a vital organ of the digestive system, with its function largely reliant on the continuous regeneration of mucosal epithelial cells by healthy intestinal stem cells (ISCs). However, as we age, the regenerative potential of ISCs declines, primarily due to deleterious aging processes, such as cellular senescence, which contribute to the development of various chronic gut diseases. A growing body of evidence indicates that both healthy ISCs, which maintain intestinal homeostasis, and aging-associated senescent ISCs are profoundly influenced by epigenetic mechanisms. At the molecular level, dynamic and often reversible epigenetic modifications including chromatin remodeling, histone modifications, DNA methylation, N6-methyladenosine (m

Nutrient surplus sensing through PI3K (phosphoinositide-3-kinase) and mTOR (mechanistic target of rapamycin) stimulates anabolism to expand cellular mass, whereas nutrient and energy deprivation sensing through SIRT1 (sirtuin-1) and AMPK (adenosine monophosphate-activated protein kinase) promotes catabolism to support cytoprotective quiescence. By signaling through downstream effectors (PGC-1α [peroxisome proliferator-activated receptor gamma coactivator 1-alpha], PPARα/PPARγ, FoxO1 [forkhead box protein family O1], NRF2 [nuclear factor erythroid-derived factor 2], HIF-1α [hypoxia-inducible factor-1α], and HO-1 [heme oxygenase-1]), environmental nutrients, growth factors, and cellular stress influence mitochondrial biogenesis, autophagic flux, cardiac hypertrophy, and cardiomyocyte senescence and apoptosis. Despite these canonical descriptions, the actual response to each effector is determined by the intensity and duration of signaling. Typically, transient and measured signaling produces adaptive effects, whereas continuous heightened activity yields maladaptive responses. The effects of signaling are also influenced by context; ie, the nature and intermittency of the external stress and the characteristics of the underlying substrate (eg, cardiomyopathy, obesity, or aging). PI3K signaling promotes physiological hypertrophy and is cardioprotective during abrupt cardiac stress, but its sustained activation accelerates pathological hypertrophy related to obesity and aging. Signaling through SIRT1/AMPK (and upregulation of autophagic flux) exerts favorable effects during exercise training and in chronic cardiomyopathy, obesity, and aging, but it undermines the cardiac response to abrupt stress. Intermittent FoxO1 upregulation may promote physiological hypertrophy while antagonizing pathological hypertrophy, but prolonged activation leads to cardiomyocyte apoptosis. NRF2 exerts antioxidant effects when background autophagic flux is vigorous but aggravates cellular stress when autophagy is suppressed (as in pathological hypertrophy). Sustained activation of PPARγ, NRF2, and HIF-1α in nutrient surplus states can lead to maladaptive ventricular remodeling, thus explaining the results of clinical trials with thiazolidinediones, bardoxolone, and prolyl hydroxylase inhibitors. The influence of duration, intensity, and context may be mediated (in part) by the activation or suppression of counterregulatory mechanisms, by the selective recruitment of corepressors, and by posttranslational protein modifications. These observations, considered collectively, suggest that no protein or cellular process viewed in isolation can be regarded as cardioprotective or maladaptive. Cell signals operate usefully if they are delivered as part of an orchestrated program of compartmentalized nuanced bursts, acting as elements of multifaceted oscillating systems whose periodicity is determined by the need to achieve homeostasis.

Brain aging is accompanied by progressive cognitive decline and increased risk of neurodegenerative diseases, with adult hippocampal neurogenesis (AHN) playing a pivotal role in maintaining cognitive resilience. Selenium, an essential trace element, exerts significant neuroprotective and neurogenic effects predominantly through its incorporation into selenoproteins, which regulate oxidative stress, neuroinflammation, and synaptic plasticity. This review synthesizes recent advances delineating selenium's metabolism, bioavailability, and its multifaceted roles in brain development, function, and aging, emphasizing mechanisms underpinning hippocampal neurogenesis. Key molecular pathways influenced by selenium include phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt)/Wingless/Integrated (Wnt) and brain-derived neurotrophic factor (BDNF)/tropomyosin receptor kinase B (TrkB) signaling pathways that promote neural progenitor cell proliferation and differentiation. Selenium transport via selenoprotein P and its receptor low-density lipoprotein receptor-related protein 8 (LRP8) is critical for adequate selenium delivery to the hippocampus to support neurogenesis, with exercise demonstrated to potentiate this axis. Selenium also mitigates ferroptosis, preserves mitochondrial integrity, and modulates neuroimmune interactions by attenuating microglial activation and inflammasome signaling, fostering a neurogenic environment. Emerging evidence highlights selenium's regulatory effects on RNA expression, including microRNAs modifications, further influencing neuronal health. Despite promising preclinical and observational data, clinical translation remains limited by heterogeneous and short-term studies. Future research priorities include multi-omics investigations, longitudinal cohorts, and addressing global selenium intake disparities through policy initiatives and precision nutrition. By consolidating mechanistic insights with clinical perspectives, this review underscores selenium's potential as a modifiable factor to enhance AHN and cognitive health, advocating for integrated translational strategies to combat brain aging and neurodegeneration.