RNA Editing Genes Associated with Extreme Old Age in Humans and with Lifespan in C. elegans

The strong familiality of living to extreme ages suggests that human longevity is genetically regulated. The majority of genes found thus far to be associated with longevity primarily function in lipoprotein metabolism and insulin/IGF-1 signaling. There are likely many more genetic modifiers of human longevity that remain to be discovered.Here, we first show that 18 single nucleotide polymorphisms (SNPs) in the RNA editing genes ADARB1 and ADARB2 are associated with extreme old age in a U.S. based study of centenarians, the New England Centenarian Study. We describe replications of these findings in three independently conducted centenarian studies with different genetic backgrounds (Italian, Ashkenazi Jewish and Japanese) that collectively support an association of ADARB1 and ADARB2 with longevity. Some SNPs in ADARB2 replicate consistently in the four populations and suggest a strong effect that is independent of the different genetic backgrounds and environments. To evaluate the functional association of these genes with lifespan, we demonstrate that inactivation of their orthologues adr-1 and adr-2 in C. elegans reduces median survival by 50%. We further demonstrate that inactivation of the argonaute gene, rde-1, a critical regulator of RNA interference, completely restores lifespan to normal levels in the context of adr-1 and adr-2 loss of function.Our results suggest that RNA editors may be an important regulator of aging in humans and that, when evaluated in C. elegans, this pathway may interact with the RNA interference machinery to regulate lifespan

Centenarian offspring: Start healthier and stay healthier

OBJECTIVES: To assess the relative incidence of age-related diseases in a group of centenarian offspring who have thus far been considered to be predisposed to healthy aging. DESIGN: Longitudinal study. SETTING: Nationwide sample. PARTICIPANTS: Four hundred forty centenarian offspring and 192 referent cohort subjects who met inclusion criteria of having initial and follow-up health questionnaire data available. Median age of both cohorts was 72 at the initial health questionnaire. MEASUREMENTS: Initial health questionnaires were collected from 1997 to 2006. Follow-up questionnaires were collected from 2004 to 2007. The mean period of follow-up was 3.5±1.7 years for the centenarian offspring and 3.9±2.2 years for the referent cohort. RESULTS: During the follow-up period, centenarian offspring had a 78% lower risk of myocardial infarction (P\u3c.04), 83% lower risk of stroke (P\u3c.004), and 86% lower risk of developing diabetes mellitus (P\u3c.005) than the referent cohort. There were no significant differences in new onset of other age-related diseases. Additionally, centenarian offspring were 81% less likely to die (P\u3c.01) than the referent cohort during the follow-up. CONCLUSION: These findings suggest that centenarian offspring retain some important cardiovascular advantages over time over similarly aged referent cohort subjects. These findings reinforce the notion that there may be physiological reasons that longevity runs in families and that centenarian offspring are more likely to age in better cardiovascular health and with a lower mortality than their peers. © 2008, Copyright the Authors

Association of longer telomeres with better health in centenarians

Prior animal model studies have demonstrated an association between telomere length and longevity. Our study examines telomere length in centenarians in good health versus poor health. Using DNA from blood lymphocytes, telomere length was measured by quantitative polymerase chain reaction in 38 sex- and age-matched centenarians (ages 97-108). Healthy centenarians (n = 19) with physical function in the independent range and the absence of hypertension, congestive heart failure, myocardial infarction, peripheral vascular disease, dementia, cancer, stroke, chronic obstructive pulmonary disease, and diabetes were compared to centenarians with physical function limitations and ≥2 of the above conditions (n = 19). Healthy centenarians had significantly longer telomeres than did unhealthy centenarians (p = .0475). Our study demonstrated that investigations of the association between telomere length and exceptional longevity must take into account the health status of the individuals. This raises the possibility that perhaps it is not exceptional longevity but one\u27s function and health that may be associated with telomere length. Copyright 2008 by The Gerontological Society of America

Serum heat shock protein 70 level as a biomarker of exceptional longevity

Heat shock proteins are highly conserved proteins that, when produced intracellularly, protect stress exposed cells. In contrast, extracellular heat shock protein 70 (Hsp70) has been shown to have both protective and deleterious effects. In this study, we assessed heat shock protein 70 for its potential role in human longevity. Because of the importance of HSP to disease processes, cellular protection, and inflammation, we hypothesized that: (1) Hsp70 levels in centenarians and centenarian offspring are different from controls and (2) alleles in genes associated with Hsp70 explain these differences. In this cross-sectional study, we assessed serum Hsp70 levels from participants enrolled in either the New England Centenarian Study (NECS) or the Longevity Genes Project (LGP): 87 centenarians (from LGP), 93 centenarian offspring (from NECS), and 126 controls (43 from NECS, 83 from LGP). We also examined genotypic and allelic frequencies of polymorphisms in HSP70-A1A and HSP70-A1B in 347 centenarians (266 from the NECS, 81 from the LGP), 260 NECS centenarian offspring, and 238 controls (NECS: 53 spousal controls and 106 septuagenarian offspring controls; LGP: 79 spousal controls). The adjusted mean serum Hsp70 levels (ng/mL) for the NECS centenarian offspring, LGP centenarians, LGP spousal controls, and NECS controls were 1.05, 1.13, 3.07, 6.93, respectively, suggesting that a low serum Hsp70 level is associated with longevity; however, no genetic associations were found with two SNPs within two hsp70 genes. © 2006 Elsevier Ireland Ltd. All rights reserved