Metabolic syndrome in the offspring of centenarians: focus on prevalence, components, and adipokines

With aging, an increased prevalence of a clustering of metabolic abnormalities has been observed. These abnormalities include obesity, dyslipidemia, hypertension, and insulin resistance and are collectively known as metabolic syndrome (MetS), a low-grade, systemic, inflammatory condition associated with an increased risk of cardiovascular disease, diabetes, and other adverse health outcomes. A number of studies have demonstrated that centenarians' offspring have a significant survival advantage and a lower risk of developing the most important age-related diseases. They therefore represent one of the best models with which to study the familiar component of human longevity. The aim of this study was to determine if the offspring of centenarians (n = 265 subjects) showed a different prevalence of MetS in comparison to the offspring of non-long-lived parents (controls, n = 101 subjects). In addition, we assessed whether centenarians' offspring showed particular features of MetS and a distinct regulation of circulating adipokines, cytokines, and metabolic mediators. Although the prevalence of MetS was quite similar both in the offspring of centenarians and the controls, MetS-affected centenarians' offspring seemed healthier, more functionally fit, and had lower resistin levels. MetS prevalence did not change in centenarians' offspring across resistin, IGF-1, and resistin/IGF-1 ratio tertiles. On the other hand, in controls, MetS prevalence strongly increased across resistin tertiles and in the third resistin/IGF-1 ratio tertile, indicating a dramatic increase in MetS prevalence when the ratio between these two factors is unbalanced, with high levels of resistin and low levels of IGF-1.

Role of epigenetics in human aging and longevity: genome-wide DNA methylation profile in centenarians and centenarians' offspring

The role of epigenetics in the modulation of longevity has not been studied in humans. To this aim, (1) we evaluated the DNA methylation from peripheral leukocytes of 21 female centenarians, their 21 female offspring, 21 offspring of both non-long-lived parents, and 21 young women through ELISA assay, pyrosequencing analysis of Alu sequences, and quantification of methylation in CpG repeats outside CpG islands; (2) we compared the DNA methylation profiles of these populations through Infinium array for genome-wide CpG methylation analysis. We observed an age-related decrease in global DNA methylation and a delay of this process in centenarians' offspring. Interestingly, literature data suggest a link between the loss of DNA methylation observed during aging and the development of age-associated diseases. Genome-wide methylation analysis evidenced DNA methylation profiles specific for aging and longevity: (1) aging-associated DNA hypermethylation occurs predominantly in genes involved in the development of anatomical structures, organs, and multicellular organisms and in the regulation of transcription; (2) genes involved in nucleotide biosynthesis, metabolism, and control of signal transmission are differently methylated between centenarians' offspring and offspring of both non-long-lived parents, hypothesizing a role for these genes in human longevity. Our results suggest that a better preservation of DNA methylation status, a slower cell growing/metabolism, and a better control in signal transmission through epigenetic mechanisms may be involved in the process of human longevity. These data fit well with the observations related to the beneficial effects of mild hypothyroidism and insulin-like growth factor I system impairment on the modulation of human lifespan.