Project description:Ageing-associated changes in the protein coding transcriptome have been extensively characterised, but less attention has been paid to the non-coding portion of the human genome, especially to long non-coding RNAs (lncRNAs). Only a minority of known lncRNAs have been functionally characterised; however, a handful of these lncRNAs have already been linked to ageing-associated processes. To gain more information on the effects of ageing on lncRNAs, we identified from GTEx data lncRNAs that show ageing-associated expression patterns (age-lncRNAs) in 29 human tissues in 20-79-year-old individuals. The age-lncRNAs identified were highly tissue-specific, but the protein coding genes co-expressed with the age-lncRNAs and the functional categories associated with the age-lncRNAs showed significant overlap across tissues. Functions associated with the age-lncRNAs, including immune system processes and transcription, were similar to what has previously been reported for protein coding genes with ageing-associated expression pattern. As the tissue-specific age-lncRNAs were associated with shared functions across tissues, they may reflect the tissue-specific fine-tuning of the common ageing-associated processes. The present study can be utilised as a resource when selecting and prioritising lncRNAs for further functional analyses.
Project description:Ageing alters cellular homeostasis thereby compromising multiple cellular processes such as transcription and splicing. However, both the extent of these changes and the molecular mechanisms are not well understood so far. In order to address this question, we analyzed transcription-coupled processes on a genomic scale in five animal species (C. elegans, D. melanogaster, M. musculus, R. norvegicus, H. sapiens) at different adult life stages. Using total RNA profiling, we quantified alterations of transcriptional elongation speed, splicing efficiency, and splicing precision. We consistently observed across all analyzed species, that the genome-average speed of RNA polymerase II (Pol-II) increased with age. These effects were reverted under lifespan-extending conditions, such as dietary restriction or modulation of insulin signaling. Reducing the speed of Pol-II in worms and flies improved splicing efficiency and increased lifespan. We further observed reduced precision in nucleosome positioning in senescent compared to proliferating cells, which correlated with reduced splicing efficiency. Thus, an age-associated increase of transcriptional speed results in reduced splicing efficiency and splicing quality. These findings substantially extend our understanding about the molecular mechanisms driving animal aging, and suggest new mechanisms underlying lifespan-extending interventions.
Project description:Ageing is the greatest risk factor for most common chronic human diseases, and it therefore is a logical target for developing interventions to prevent, mitigate or reverse multiple age-related morbidities. Over the past two decades, genetic and pharmacologic interventions targeting conserved pathways of growth and metabolism have consistently led to substantial extension of the lifespan and healthspan in model organisms as diverse as nematodes, flies and mice. Recent genetic analysis of long-lived individuals is revealing common and rare variants enriched in these same conserved pathways that significantly correlate with longevity. In this Perspective, we summarize recent insights into the genetics of extreme human longevity and propose the use of this rare phenotype to identify genetic variants as molecular targets for gaining insight into the physiology of healthy ageing and the development of new therapies to extend the human healthspan.
Project description:Only two genome-wide significant loci associated with longevity have been identified so far, probably because of insufficient sample sizes of centenarians, whose genomes may harbor genetic variants associated with health and longevity. Here we report a genome-wide association study (GWAS) of Han Chinese with a sample size 2.7 times the largest previously published GWAS on centenarians. We identified 11 independent loci associated with longevity replicated in Southern-Northern regions of China, including two novel loci (rs2069837-IL6; rs2440012-ANKRD20A9P) with genome-wide significance and the rest with suggestive significance (P < 3.65 × 10(-5)). Eight independent SNPs overlapped across Han Chinese, European and U.S. populations, and APOE and 5q33.3 were replicated as longevity loci. Integrated analysis indicates four pathways (starch, sucrose and xenobiotic metabolism; immune response and inflammation; MAPK; calcium signaling) highly associated with longevity (P ≤ 0.006) in Han Chinese. The association with longevity of three of these four pathways (MAPK; immunity; calcium signaling) is supported by findings in other human cohorts. Our novel finding on the association of starch, sucrose and xenobiotic metabolism pathway with longevity is consistent with the previous results from Drosophilia. This study suggests protective mechanisms including immunity and nutrient metabolism and their interactions with environmental stress play key roles in human longevity.
Project description:Backgroundoffspring of long-lived individuals have lower risk for dementia. We examined the relation between parental longevity and cognition and subclinical markers of brain ageing in community-dwelling adult offspring.Methodsoffspring participants with both parents in the Framingham Heart Study, aged ?55 years and dementia-free underwent baseline and repeat neuropsychological (NP) testing and brain magnetic resonance imaging (MRI). Parental longevity was defined as having at least one parent survive to age ?85 years. To test the association between parental longevity and measures of cognition and brain volumes, we used multivariable linear and logistic regression adjusting for age, sex, education and time to NP testing or brain MRI.Resultsof 728 offspring (mean age 66 years, 54% women), 407 (56%) had ?1 parent achieve longevity. In cross-sectional analysis, parental longevity was associated with better scores on attention (beta 0.21 ± 0.08, P = 0.006) and a lower odds of extensive white matter hyperintensity on brain MRI (odds ratio 0.59, 95% CI: 0.38, 0.92, P = 0.019). The association with white matter hyperintensity was no longer significant in models adjusted for cardiovascular risk factors and disease. In longitudinal analysis (6.7 ± 1.7 years later), offspring with parental longevity had slower decline in attention (0.18 ± 0.08, P = 0.038), executive function (beta 0.19 ± 0.09, P = 0.031) and visual memory (beta -0.18 ± 0.08, P = 0.023), and less increase in temporal horn volume (beta -0.25 ± 0.09, P = 0.005). The associations persisted in fully adjusted models.Conclusionparental longevity is associated with better brain ageing in middle-aged offspring.
Project description:Objective:to examine the association of parental longevity with healthy survival to age 90 years. Methods:this was a prospective study among a racially and ethnically diverse cohort of 22,735 postmenopausal women from the Women's Health Initiative recruited from 1993 to 1998 and followed through 2017. Women reported maternal and paternal ages at death and current age of alive parents. Parental survival categories were <70, 70-79 (reference), 80-89 and ≥90 years (longevity). Healthy ageing was defined as reaching age 90 without major chronic conditions (coronary heart disease, stroke, diabetes, cancer, or hip fracture) or physical limitations. Results:women whose mothers survived to ≥90 years were more likely to attain healthy ageing (OR, 1.25; 95% CI, 1.11-1.42) and less likely to die before age 90 (OR, 0.75; 95% CI, 0.68-0.83). Women whose fathers survived to ≥90 years did not have significantly increased odds of healthy ageing but showed 21% (OR, 0.79; 95% CI, 0.70-0.90) decreased odds of death before age 90. Women whose mother and father both lived to 90 had the strongest odds of healthy ageing (OR, 1.38; 95% CI, 1.09-1.75) and decreased odds of death (OR, 0.68; 95% CI, 0.54-0.85). The proportion of healthy survivors was highest among women whose mother and father lived to 90 (28.6%), followed by those whose mother only lived to 90 (23.2%). Conclusions:parental longevity predicted healthy ageing in a national cohort of postmenopausal women, supporting the view that genetic, environmental, and behavioral factors transmitted across generations may influence ageing outcomes among offspring.
Project description:Reproductive longevity is essential for fertility and influences healthy ageing in women1,2, but insights into its underlying biological mechanisms and treatments to preserve it are limited. Here we identify 290 genetic determinants of ovarian ageing, assessed using normal variation in age at natural menopause (ANM) in about 200,000 women of European ancestry. These common alleles were associated with clinical extremes of ANM; women in the top 1% of genetic susceptibility have an equivalent risk of premature ovarian insufficiency to those carrying monogenic FMR1 premutations3. The identified loci implicate a broad range of DNA damage response (DDR) processes and include loss-of-function variants in key DDR-associated genes. Integration with experimental models demonstrates that these DDR processes act across the life-course to shape the ovarian reserve and its rate of depletion. Furthermore, we demonstrate that experimental manipulation of DDR pathways highlighted by human genetics increases fertility and extends reproductive life in mice. Causal inference analyses using the identified genetic variants indicate that extending reproductive life in women improves bone health and reduces risk of type 2 diabetes, but increases the risk of hormone-sensitive cancers. These findings provide insight into the mechanisms that govern ovarian ageing, when they act, and how they might be targeted by therapeutic approaches to extend fertility and prevent disease.
Project description:Abstract Role of genetic interactions (GxG) in human longevity remains poorly understood. We hypothesized that GxG between genes from biologically connected pathways involved in aging may impact longevity. To test this hypothesis, we selected 53 candidate genes from the aging-related pathways (IGF-1/AKT/FOXO3A, TP53/P21/P16, and mTOR/S6K mediated) that are known to jointly influence outcomes of cell responses to stress and damage, such as apoptosis, senescence, growth/proliferation, and autophagy. We evaluated the effects of interactions between SNPs in these genes on longevity in LLFS and CARe data. RESULTS: The IGF1R, PPARGC1A and BCL2 genes were consistently involved in top GxG effects (p<10-6) on survival in the oldest old (85+ and 95+). One SNP, rs2970870 in PPARGC1A gene, was broadly involved in significant interaction effects on survival 96+ (p<10-7) when paired with SNPs in IGF1R and NFKB1 genes. This SNP individually was associated with survival with nominal significance only; therefore, it would have not been selected in a GWAS. We conclude that interactions between genes from aging-related pathways that regulate cell responses and resilience to damage may have major impact on human longevity and contribute to its genetic heterogeneity. The research was supported by the NIA/NIH grants R01AG062623, U19AG063893, P01AG043352.
Project description:Human longevity is a complex phenotype with a significant familial component, yet little is known about its genetic antecedents. Increasing evidence from animal models suggests that the insulin/IGF-1 signaling (IIS) pathway is an important, evolutionarily conserved biological pathway that influences aging and longevity. However, to date human data have been scarce. Studies have been hampered by small sample sizes, lack of precise phenotyping, and population stratification, among other challenges. Therefore, to more precisely assess potential genetic contributions to human longevity from genes linked to IIS signaling, we chose a large, homogeneous, long-lived population of men well-characterized for aging phenotypes, and we performed a nested-case control study of 5 candidate longevity genes. Genetic variation within the FOXO3A gene was strongly associated with human longevity. The OR for homozygous minor vs. homozygous major alleles between the cases and controls was 2.75 (P = 0.00009; adjusted P = 0.00135). Long-lived men also presented several additional phenotypes linked to healthy aging, including lower prevalence of cancer and cardiovascular disease, better self-reported health, and high physical and cognitive function, despite significantly older ages than controls. Several of these aging phenotypes were associated with FOXO3A genotype. Long-lived men also exhibited several biological markers indicative of greater insulin sensitivity and this was associated with homozygosity for the FOXO3A GG genotype. Further exploration of the FOXO3A gene, human longevity and other aging phenotypes is warranted in other populations.
Project description:Senescence or ageing is an increase in mortality and/or decline in fertility with increasing age. Evolutionary theories predict that ageing or longevity evolves in response to patterns of extrinsic mortality or intrinsic damage. If ageing is viewed as the outcome of the processes of behaviour, growth and reproduction then it should be possible to predict mortality rate. Recent developments have shown that it is now possible to integrate these ecological and physiological processes and predict the shape of mortality trajectories. By drawing on the key exciting developments in the cellular, physiological and ecological process of longevity the evolutionary consequences of ageing are reviewed. In presenting these ideas an evolutionary demographic framework is used to argue how trade-offs in life-history strategies are important in the maintenance of variation in longevity within and between species. Evolutionary processes associated with longevity have an important role in explaining levels of biological diversity and speciation. In particular, the effects of life-history trait trade-offs in maintaining and promoting species diversity are explored. Such trade-offs can alleviate the effects of intense competition between species and promote species coexistence and diversification. These results have important implications for understanding a number of core ecological processes such as how species are divided among niches, how closely related species co-occur and the rules by which species assemble into food-webs. Theoretical work reveals that the proximate physiological processes are as important as the ecological factors in explaining the variation in the evolution of longevity. Possible future research challenges integrating work on the evolution and mechanisms of growing old are briefly discussed.