GeroScience

Young blood plasma is known to confer beneficial effects on various organs in mice. However, it was not known whether young plasma rejuvenates cells and tissues at the epigenetic level; whether it alters the epigenetic clock, which is a highly-accurate molecular biomarker of aging. To address this question, we developed and validated six different epigenetic clocks for rat tissues that are based on DNA methylation values derived from n=593 tissue samples. As indicated by their respective names, the rat pan-tissue clock can be applied to DNA methylation profiles from all rat tissues, while the rat brain-, liver-, and blood clocks apply to the corresponding tissue types. We also developed two epigenetic clocks that apply to both human and rat tissues by adding n=850 human tissue samples to the training data. We employed these six clocks to investigate the rejuvenation effects of a plasma fraction treatment in different rat tissues. The treatment more than halved the epigenetic ages of blood, heart, and liver tissue. A less pronounced, but statistically significant, rejuvenation effect could be observed in the hypothalamus. The treatment was accompanied by progressive improvement in the function of these organs as ascertained through numerous biochemical/physiological biomarkers and behavioral responses to assess cognitive functions. Cellular senescence, which is not associated with epigenetic aging, was also considerably reduced in vital organs. Overall, this study demonstrates that a plasma-derived treatment markedly reverses aging according to epigenetic clocks and benchmark biomarkers of aging.

Frailty, defined by progressive loss of physiological resilience, neuromuscular function, and cognitive capacity, is a central manifestation of biological aging yet remains difficult to quantify in scalable experimental systems. Here, we introduce a Composite Frailty Index (CFI) in the house cricket (Acheta domesticus) that integrates automated measures of locomotion, exploratory behavior, and freezing into a unified, quantitative framework of functional decline. Ten behavioral parameters derived from automated open-field tracking, including locomotor performance, exploratory behavior, and freezing were integrated into the CFI. Locomotor states were classified using k-means clustering (k = 2) of velocity distributions, and all features were normalized to age- or treatment-matched reference populations, discretized into quintiles, and summed to generate a 0-40 frailty score. Aging cohorts (young adult: 4-6 weeks; geriatric: 10-12 weeks, N = 103) and pharmacological cohorts treated at mid-life (8-10 weeks) with rapamycin (14 ppm), acarbose (1000 ppm), or phenylbutyrate (1000 ppm) were evaluated (N = 122). Across chronological aging cohorts, CFI increased from young adults to geriatrics in both females (d = 1.14 [95% CI: 0.53, 1.76], P = 0.0003) and males (d = -1.17 [95% CI: -1.75 to -0.59], P < 0.0001). Using pharmacological intervention cohorts, mid-life rapamycin treatment reduced late-life frailty relative to controls in both females (d = -1.31 [95% CI: -2.09, -0.53], P = 0.0017) and males (d = -1.33 [95% CI: -2.09, -0.58], P = 0.0004), whereas acarbose and phenylbutyrate produced inconclusive effects (ds = -0.54 to -0.03; Ps > 0.05). Together, these findings establish the cricket CFI as a scalable, high-throughput platform for quantifying multidimensional functional aging and prioritizing candidate geroprotective interventions based on clinically relevant endpoints beyond lifespan.

DNA methylation data have been successfully used to develop highly accurate estimators of age ("epigenetic clocks") in many mammalian species. With a view of extending such epigenetic clocks to all primate species, we analyzed DNA methylation profiles of 2400 tissues derived from 37 primate species including 11 haplorhine species (baboons, marmosets, vervets, rhesus macaque, chimpanzees, gorillas, orangutan, humans) and 26 strepsirrhine species (suborders Lemuriformes and Lorisiformes). From these we present here, pan-primate epigenetic clocks which are highly accurate for all primates including humans (age correlation R=0.98). We also carried out in-depth analysis of baboon DNA methylation profiles and generated five epigenetic clocks for baboons (Olive-yellow baboon hybrid), one of which, the pan-tissue epigenetic clock, was trained on seven tissue types (fetal cerebral cortex, adult cerebral cortex, cerebellum, adipose, heart, liver, and skeletal muscle) with ages ranging from late fetal life to 22.8 years of age. To facilitate translation of findings in baboons to humans, we further constructed two dual-species, human-baboon clocks. We also identified and present here, epigenetic predictors of sex that apply to all primate species. Low overlap can be observed between age- and sex-related CpGs. Overall, this study advances our understanding of conserved age- and sex-related epigenetic changes in primates, and provides biomarkers to study the aging of all primate species with the facility to readily translate any findings between primate species.

Although aging is a universal event, some individuals are able to achieve extreme longevity. The Long-Life Family Study (LLFS) enrolls participants from families enriched with long-lived individuals, serves as a valuable dataset for studying ageing phenotypes and identify potential intervention targets. We analyzed the association between age at blood draw and 16,284 RNAseq-based blood transcriptomic data from 2,167 LLFS participants with ages ranging from 18 to 107, replicated the results in the Integrative Longevity Omics Study (ILO) dataset of 20,884 RNAseq-based blood transcriptomic data from 419 participants, with ages ranging from 60 to 108, and further compared our findings to a published reference aging signature. We identified 4,227 transcripts increasing and 4,044 transcripts decreasing with age, and enrichment analysis revealed age-related upregulation of inflammatory and senescence-related pathways, and downregulation of MYC and Wnt/{beta}-catenin targets, among others. Further, a subset of transcripts showed age associations unique to the longevity-enriched cohorts (LLFS and ILO). We also identified 314 transcripts significantly associated with mortality risk and found that pro-survival gene sets included NK cell-mediated cytotoxicity and GPCR signaling. Finally, increased transcriptomic age predicted using transcriptomic clock was strongly associated with increased mortality. In summary, this study identified robust transcriptomic signatures of aging and mortality in a longevity-enriched population, highlighting key biological pathways such as immune modulation, inflammation, and senescence. Authors notesThis manuscript has been peer-reviewed and accepted by GeroScience (Springer). This bioRxiv article reflects the published version, incorporating revisions made in response to reviewers comments. The main content, results, and conclusions remain unchanged from the previous version, while the Discussion section has been expanded to further address the functional annotation and clinical relevance of the identified markers. Copy of the acceptance letterThe editors are pleased to inform you that your manuscript, JAAA-D-25-01946R1 entitled "Whole blood transcriptional signatures of age and survival identified in Long Life Family and Integrative Longevity Omics Studies" has been accepted for publication in GeroScience as an Original Article. The editors commend you on your outstanding contribution to the journal. Your manuscript can be published online ahead of print within approximately two weeks.

Antagonistic pleiotropy of the IGF-1 signaling cascade is well recognized, as it promotes growth and development at younger ages and delays aging later in life. The goal of this study is to test in a mouse longevity experiment whether orally delivered small-molecule IGF1R inhibitors have promise as an anti-aging therapy. C57BL/6 mice (25 male and 25 female mice per treatment) were treated with selective IGF1R inhibitors, picropodophyllin (PPP) or 5-[3-(phenylmethoxy)phenyl]-7-[trans-3-(1-pyrrolidinylmethyl)cyclobutyl]-7H-pyrrolo[3-d]pyrimidin-4-amine (NVP-ADW742), via powdered diets starting at 13 months of age, and physiological and behavioral parameters, as well as survival, were assessed. Both compounds protected both sexes from short-term memory decline; reduced systolic blood pressure in males and pulse rate in both sexes; rescued declining glucose tolerance in males; and abolished grey hair development, reduced frailty, and protected against decline in grip strength in female mice. There were no sex differences in survival curves within groups. No significant differences between groups were observed in the Kaplan-Meier analysis. However, the survival curve in the NVP-ADW742 group was "squarer" than in controls, indicating a 93-day longer healthspan (p = 0.02). PPP treatment was associated with toxicity (GI bleeding). Additional analysis of the drug likeness of NVP-ADW742 demonstrated potential cardiotoxicity and brain bioaccumulation. To conclude, small-molecule IGF1R inhibitors hold promise as a therapy that may improve human health span and lifespan; however, both molecules tested in this study have side effects that may outweigh their anti-aging effects. Statements and DeclarationsYB is an employee of ReGENE LLC. GB received compensation from ReGENE LLC as a consultant. CJE received compensation from and is a member of ReGENE LLC. AS received compensation from and is a member of ReGENE LLC. TS declares no conflict of interest.

The female longevity advantage--averaging 4-6 years globally--stems from reduced susceptibility to inflammaging, the chronic, low-grade inflammation driving age-related diseases like fibrosis and cardiovascular decline [10]. Interleukin-11 (IL-11), a gp130-family cytokine, has emerged as a pivotal inflammaging mediator: Its genetic or pharmacological inhibition extends mouse median lifespan by 22.5% in males and 25% in females, with enhanced healthspan benefits in the latter [20-29]. Here, we propose that estrogens direct suppression of IL-11 transcription--via estrogen receptor- (ER)-mediated interference with NF-{kappa}B/AP-1 on the IL-11 promoter in osteoblasts, fibroblasts, and endothelial cells-- establishes a pre-menopausal "hormonal firewall" against IL-11-driven senescence and multi-organ fibrosis [0-9]. In contrast, testosterone exhibits neutral or permissive effects, correlating with elevated IL-11 in hyperandrogenic states like polycystic ovary syndrome (PCOS) [30-40]. To test this, we developed an ordinary differential equation (ODE) model integrating IL-11 dynamics with upstream triggers (e.g., Ang II, c-Myc/miR-23 derepression) and suppressors (SIRT1 deacetylates IL-11 promoter histones; p53 represses IL-11/c-Myc; NRF2 quenches NF-{kappa}B) [10,12]. In persistent inflammaging simulations (impaired degradation, k_deg=0.1), high estrogen (1.0 arbitrary units) reduced steady-state IL-11 by 63% (179.96 to 65.77 at t=20 days), cascading to 40-50% lower STAT3/NF-{kappa}B activation and triad cytokines (TNF-/IL-6/IL-1{beta}) [11,13]. Synergy with high SIRT1/p53/NRF2 amplified suppression to [~]74% for IL-11 [16,17]. Post-menopausal estrogen decline erodes this buffer, but cumulative pre-menopausal protection persists, explaining sustained sex gaps post-65 [32,34]. This framework predicts estrogen replacement therapy (HRT) could mitigate inflammaging equitably, narrowing longevity disparities [35]. Validation via sex-stratified IL-11 cohorts and HRT-fibrosis trials is warranted, positioning IL-11 as a sex-specific therapeutic nexus.

Sexes frequently differ in life history traits including body size, lifespan, and age at sexual maturity. Aging, the progressive decline in physiological function and cellular resilience over time, is a central process contributing to sex-specific life histories, yet the mechanisms driving sex differences in aging remain largely unresolved. Long-term mark-recapture efforts revealed a striking pattern of female-biased longevity in the painted turtle (Chrysemys picta), a species with temperature-dependent sex determination. As a result, this species provides a compelling system to examine the mechanisms of sex-specific aging in the absence of sex chromosomes. Here, we characterize sex- and age-associated patterns in the blood transcriptomes of wild painted turtles (n = 93). We identified widespread gene expression differences between females and males (2,347 genes; 13.4% of all filtered genes). In contrast, only six genes showed significant linear relationships with continuous age in both sexes. We also employed a machine learning approach which identified distinct sets of genes for which expression was predictive of age in each sex. Age-related gene expression patterns highlight both conserved molecular pathways with known roles in aging as well as novel gene targets. These findings suggest sex-specific molecular processes underlie sex-biased demographic aging and raise questions regarding the environmental and developmental drivers of sex-biased gene expression.

Despite being principally prescribed to treat type 2 diabetes, biguanides, especially metformin and phenformin, have been shown to extend lifespan and healthspan in preclinical models, and to reduce the impact of aging-associated diseases such as cancer. While there have been conflicting results in studies involving rodents and humans, consistent evidence from laboratories worldwide, including our own, indicates metformin and phenformins ability to significantly extend lifespan in C. elegans. However, the pro-longevity effect of metformin can vary depending on environmental conditions. Specifically, the choice of agar from different manufacturers or batches influences metformins ability to extend lifespan in C. elegans. We traced ability of certain agar batches to interfere with metformin-prompted lifespan extension to the presence of a factor that acts directly in the worm, independently of the bacterial food source, that prevents longevity promoting effects downstream of longevity effectors skn-1 and AMPK. In contrast, phenformin prompts robust lifespan extension in the face of environmental changes and exhibits broad positive effects in aging across genetically diverse Caenorhabditis species where the impact of metformin is highly variable. Thus metformin effects in aging are impacted by heretofore unappreciated environmental factors. Phenformin may represent a more robust agent with which to understand the longevity promoting mechanisms downstream of biguanides.

Analysis of preclinical lifespan studies often assume that outcome data from co-housed animals are indepen-dent. In practice, treatments, such as controlled feeding or putative life-extending compounds, are applied to whole housing units, and as a result the outcomes are potentially correlated within housing units. We consider intra-class (here, intra-cage) correlation in three published and two unpublished lifespan studies of aged mice encompassing more than 20 thousand observations. We show that the independence assumption underlying common analytic techniques does not hold in these data, particularly for traits associated with frailty. We describe and demonstrate various analytical tools available to accommodate this study design and highlight a limitation of standard variance components models (i.e., linear mixed models) which are the usual statisti-cal tool for handling correlated errors. Through simulations, we examine the statistical biases resulting from intra-cage correlations with similar magnitudes as observed in these case studies and discuss implications for power and reproducibility.

Insulin/insulin growth factor signaling is a conserved pathway that regulates lifespan across many species. Multiple mechanisms are proposed for how this altered signaling slows aging. To elaborate these causes, we recently developed a series of Drosophila insulin-like receptor (dInr) mutants with single amino acid substitutions that extend lifespan but differentially affect insulin sensitivity, growth and reproduction. Transheterozygotes of canonical dInr mutants (Type I) extend longevity and are insulin-resistant, small and weakly fecund. In contrast, a dominant mutation (dInr353, Type II) within the Kinase Insert Domain (KID) robustly extends longevity but is insulin-sensitive, full-sized, and highly fecund. We applied transcriptome and metabolome analyses to explore how dInr353 slows aging without insulin resistance. Type I and II mutants overlap in many pathways but also produce distinct transcriptomic profiles that include differences in innate immune and reproductive functions. In metabolomic analyses, the KID mutant dInr353 reprograms methionine metabolism in a way that phenocopies dietary methionine restriction, in contrast to canonical mutants which are characterized by upregulation of the transsulfuration pathway. Because abrogation of S-adenosylhomocysteine hydrolase blocks the longevity benefit conferred by dInr353, we conclude the methionine cycle reprogramming of Type II is sufficient to slow aging. Metabolomic analysis further revealed the Type II mutant is metabolically flexible: unlike aged wildtype, aged dInr353 adults can reroute methionine toward the transsulfuration pathway, while Type I mutant flies upregulate the trassulfuration pathway continuously from young age. Altered insulin/insulin growth factor signaling has the potential to slow aging without the complications of insulin resistance by modulating methionine cycle dynamics. Author SummaryMutations in the invertebrate insulin/IGF signaling system robustly extend lifespan. Yet these interventions often cause insulin resistance, reduce growth, and impair fertility. In contrast, a dominant gain-of-function mutation in the kinase insert domain of the Drosophila insulin/IGF receptor extends lifespan while maintaining insulin sensitivity, growth, or reproduction. Here, we demonstrate this unique mutation reprograms methionine metabolism pathway in a way that mirrors dietary methionine restriction, which is known to extend lifespan in several animals including Drosophila and mice. Genetic epistasis analysis verifies this methionine cycle inhibition is an underlying cause for how the kinase insert domain mutation slows Drosophila aging while maintaining insulin-sensitivity, growth, and fecundity.

Aging studies in mammalian models often depend on natural lifespan data as a primary outcome. Tools for lifespan prediction could accelerate these studies and reduce the need for veterinary intervention. Here, we leveraged large-scale longitudinal frailty and lifespan data on two genetically distinct mouse cohorts to evaluate noninvasive strategies to predict life expectancy in mice. We applied a modified frailty assessment, the Fragility Index, derived from existing frailty indices with additional deficits selected by veterinarians. We developed an ensemble machine learning classifier to predict imminent mortality (95% proportion of life lived [95PLL]). Our algorithm represented improvement over previous predictive criteria but fell short of the level of reliability that would be needed to make advanced prediction of lifespan and thus accelerate lifespan studies. Highly sensitive and specific frailty-based predictive endpoint criteria for aged mice remain elusive. While frailty-based prediction falls short as a surrogate for lifespan, it did demonstrate significant predictive power and as such must contain information that could be used to inform the conclusion of aging experiments. We propose a frailty-based measure of healthspan as an alternative target for aging research and demonstrate that lifespan and healthspan criteria reveal distinct aspects of aging in mice.

Single-ingredient dietary supplements have demonstrated some potential to extend lifespan and improve healthspan; however, the efficacy of defined multi-ingredient nutraceuticals remains underexplored. Senolytic interventions have been successful in reducing multi-morbidity, frailty, and cognitive decline in animal models and are seen as promising anti-ageing interventions in mammals. We compared the effects of a 12-ingredient nutraceutical on mice lifespan and healthspan markers with that of a high efficacy senolytic intervention consisting of a low dose of Navitoclax combined with the specific mitochondrial uncoupler BAM15. Both interventions were started at old age (20 months). The supplement was given daily until the end of the experiment (30 months of age), but the senolytic intervention consisted of two short (5 days each) rounds of treatment at 20 and 23 months of age. Despite late onset, both interventions increased median lifespan similarly by around 20% over controls. The senolytic intervention significantly reduced frailty progression and improved cognitive function after the second round of treatment, but without subsequent treatment, these effects appeared to wane at later ages. The multi-ingredient supplement tended to reduce frailty progression steadily with time, albeit not significant, and maintained cognitive function. Mechanistically, in vitro, there was no evidence of senolytic activity of the multi-ingredient nutraceutical as a whole nor of its individual ingredients. Continuous multi-ingredient dietary supplementation shows promise in achieving comparable anti-ageing efficacy as a senolytic intervention.

BackgroundLow-dose rapamycin promotes longevity in mice, but clinical safety and longevity data effects in humans remain limited. ObjectivesEvaluate the long-term safety of intermittent low-dose rapamycin in a healthy, normative-aging human cohort. DesignThis decentralized double-blinded, randomized, placebo-controlled trial (NCT04488601, registered 2020-07-28) was performed over 48 weeks. Participants received placebo, 5mg or 10mg compounded rapamycin (equivalent to 1.43mg or 2.86mg of generic formulations) weekly. The primary outcome measure was visceral adiposity (by DXA scan), secondary outcomes were blood biomarkers, and lean tissue and bone mineral content (by DXA scan). Established surveys were utilized to evaluate health and well-being. Safety was assessed through adverse events and blood biomarker monitoring. ResultsAdverse and serious adverse events were similar across all groups. Visceral adiposity did not change significantly ({eta}p2=0.001, p=0.942), and changes in blood biomarkers remained within normal ranges. Lean tissue mass ({varepsilon}2=0.202, p=0.013) and self-reported pain ({varepsilon}2=0.168, p=0.015) improved significantly for women using 10mg rapamycin. Trends of improvement in bone mineral density were observed in males using 10mg rapamycin ({varepsilon}2=0.221, p=0.061), but no other significant effects were observed. ConclusionsLow-dose, intermittent rapamycin administration over 48 weeks is relatively safe in healthy, normative-aging adults, and was associated with significant improvements in lean tissue mass and pain in women. Future work will evaluate benefits of a broader range of rapamycin doses on healthspan metrics for longevity, and will aim to more comprehensively establish efficacy.

Five of the seven extant wild species of the genus Equus are species of significant conservation concern. Effective conservation and management of such threatened wildlife populations depends on the ability to estimate demographic trends and population viability and therefore requires accurate assessment of age structure. However, reliably aging wildlife is challenging as many methods are highly invasive, inaccurate, or both. Epigenetic aging models, which estimate individual age with high accuracy based on genomic methylation patterns, are promising developments in this regard. Importantly, epigenetic aging models developed for one species can potentially predict age with high accuracy in sister taxa. Using blood and biopsy samples from known age plains zebras (Equus quagga), we developed epigenetic clocks (ECs) to predict chronological age, and epigenetic pacemaker (EPM) models to predict biological age. We tested the ability of our blood-based EC to predict ages of Grevys zebras, Somali asses and domestic horses, from blood samples. Because our samples came from a population with a complex pedigree, we also leveraged information from a previous sequencing effort to measure the association between levels of inbreeding (F and ROH) and the age acceleration as measured by DNA methylation. The resulting models describe the trajectory of epigenetic aging in plains zebras and accurately predict the ages of plains zebras and other equids. We found moderate support for a slight acceleration of aging with increased inbreeding.

IntroductionEpigenetic clocks based on DNA methylation patterns provide a powerful tool for measuring biological ageing, but requiring genome-wide methylation data and high costs limits their broad application across species and populations. MethodsWe investigated whether simply quantifying global DNA methylation levels could serve as an inexpensive proxy for epigenetic ageing, using a captive colony of owl monkeys (Aotus nancymaae) using a colorimetric ELISA assay to measure proportional content of levels of blood and brain 5-methylcytosine (5-mC) across the genome, comparing owl monkeys with known exposures to ageing accelerators and controls. Resultswe found that global 5-mC declined significantly with chronological age in blood, and in the brain of parents. Notably, this age-related blood hypomethylation in individuals experiencing early life maternal rejection was accelerated. Parenting experience also accelerated DNA methylation loss with age, but this effect was specific to the brain and not seen in blood. Infection history did not impact blood 5-mC trajectories. Although multiple regression models did not replicate all findings, likely due to sample size constraints, our results demonstrate that global DNA hypomethylation tracks biological ageing in blood. DiscussionThis simple metric successfully detected accelerated epigenetic ageing induced by early adversity, as well as distinct patterns relating to reproductive investment in the brain - phenotypes typically identified by sophisticated epigenetic clocks. Quantifying global methylation thus provides a cost-effective alternative approach to assessing susceptibility to environmentally-driven accelerated ageing across primate species and populations where DNA methylation arrays or sequencing are impractical.

Sulforaphane, an organosulfur isothiocyanate derived from cruciferous vegetables, has been shown to inhibit inflammation, oxidative stress, and cancer cell growth. To explore the potential of sulforaphane as a candidate natural compound for promoting longevity more generally, we tested the dose and age-specific effects of sulforaphane on C. elegans longevity, finding that it can extend lifespan by more than 50% at the most efficacious doses, but that treatment must be initiated early in life to be effective. We then created a novel, gene-specific, transcriptional aging clock, which demonstrated that sulforaphane-treated individuals exhibited a "transcriptional age" that was approximately four days younger than age-matched controls, representing a nearly 20% reduction in biological age. The clearest transcriptional responses were detoxification pathways, which, together with the shape of the dose-response curve, indicates a likely hormetic response to sulforaphane. These results support the idea that robust longevity-extending interventions can act via global effects across the organism, as revealed by systems level changes in gene expression.

Rapamycin, also known as sirolimus, has demonstrated great potential for application in longevity medicine. However, the bioavailability of generic and compounded rapamycin at longevity doses in normative aging individuals remains unknown. We conducted a retrospective, real-world study determining the 24-hour blood rapamycin levels to establish the relative bioavailability, dose-to-blood level linearity and inter-individual heterogeneity in a normative aging cohort. Participants received either compounded rapamycin (n = 23, dosages 5, 10, or 15 mg) or generic rapamycin (n= 44, dosages 2, 3, 6, or 8 mg) once per week, and were asked to obtain a sirolimus level blood draw 24 hours after dose self-administration. Similar blood rapamycin levels and a linear dose-to-blood level relationship were observed for both formulations, although a higher bioavailability per milligram of rapamycin was noted for the generic formulation (compounded averaged 0.287 (28.7%) bioavailability relative to generic rapamycin in (ng/mL) / mg rapamycin). While substantial inter-individual heterogeneity in blood rapamycin levels was observed for both formulations, repeat tests for individuals demonstrated high test-retest reliability. As we detected no significant association between bioavailability and measures of body mass index (BMI), sex, age, or length of time taking rapamycin, we suggest that individualized dosing and routine monitoring of blood rapamycin levels should be applied to ensure optimal longevity efficacy. Finally, we contextualize our data with a brief review of the literature on the currently available knowledge of rapamycins bioavailability in normative aging populations, and provide implications for the clinical use of rapamycin in longevity medicine moving forward.

Age-related decline in mobility and cognition are associated with cellular senescence and NAD+ depletion in dogs and people. A combination of a novel NAD+ precursor and senolytic, LY-D6/2 was examined in this randomized controlled trial. Seventy dogs were enrolled and allocated into placebo, low or full dose groups. Primary outcomes were change in cognitive impairment measured with the owner-reported Canine Cognitive Dysfunction Rating (CCDR) scale and change in activity measured with physical activity monitors. Fifty-nine dogs completed evaluations at the three-month primary endpoint, and 51 reached the six-month secondary endpoint. There was a significant difference in CCDR score across treatment groups from baseline to the primary endpoint (p=0.02) with the largest decrease in the full dose group. There were no significant differences between groups in changes in measured activity. However, the proportion of dogs that improved in frailty and owner-reported activity levels and happiness was higher in the full dose group than other groups. Adverse events occurred equally across groups. All groups showed improvement in cognition, frailty, and activity suggesting placebo effect and benefits of trial participation. We conclude that LY-D6/2 significantly improves owner-assessed cognitive function and may have broader effects on frailty, activity and happiness as reported by owners.

Quantifying biological aging is crucial for understanding functional decline before the onset of morbidity. While many accelerated aging and frailty measures based on clinical data exist for humans and several for rodent models of aging, there are few options for non-human primates (NHPs). NHP clinical data has several unique features including a lack of clinically delineated normative values for features and variability in data collection over long lifespans. There are also wide discrepancies in the number of available clinical measures and number of animals across data sets. To address these challenges, we developed and validated "Aging Resilience" (AR) metrics using longitudinal, routine clinical data from two distinct non-human primate cohorts: 4,328 baboons and 281 rhesus macaques. We trained five computational models--including Linear Mixed-Effects Models, Random Forest, and Recurrent Neural Networks (RNN)--to predict chronological age, subsequently deriving AR metrics that represent the velocity (Rate of Aging) and cumulative burden (Normalized Cumulative Aging) of physiological deviation. While linear models achieved high precision in predicting chronological age (test R2 up to 0.99), they correlated poorly with actual lifespan. In contrast, AR metrics derived from non-linear models (RNN and Random Forest) displayed strong predictive validity for mortality (Pearsons r > 0.8). These findings highlight a critical paradox: models that best predict chronological age do not necessarily capture the biological resilience determining healthspan. This study establishes a scalable framework for monitoring biological aging in translational models using standard veterinary records.

Valid animal models are needed to evaluate how age-related changes in kidney function influence healthspan. Aging marmosets frequently develop renal insufficiency with anemia and exhibit reductions in body mass and metabolic rate. However, it remains unclear which age-related changes predict survival and which thresholds indicate increased mortality risk. We prospectively evaluated age, body composition, resting energy expenditure, hematology, and blood chemistry as predictors of 3-year survival in female and male marmosets (n = 66), 2-16 years of age. Objectives were to identify prognostic markers, define high-risk thresholds, and to develop and test a composite risk-factor scale for mortality screening in captivity. A 10-variable model showed the best predictive performance in multivariable Cox proportional hazards modeling, and was retained for further analysis (concordance = 0.881, p < 0.001). ROC curves using Youdens Index and AUC identified high-risk thresholds for predictors in the multivariable model, and threshold-defined categories were evaluated by Kaplan-Meier survival analysis. The 10 binary risk-factors were combined into a composite scale scored from 0 to 10 and tested with Cox regression. The scale explained approximately 42% of variance in survival and each additional risk factor increased mortality risk 1.75-fold (95% CI: 1.43-2.14, p < 0.001). Marmosets with [&ge;]7 risk factors exhibited a 19-month reduction in survival, and this high-risk threshold predicted 3-year survival with 89.4% accuracy. Results support the scale as a screening tool for mortality risk and highlight the high prevalence of age-associated renal disease and anemia in marmosets.