Project description:Various risk factors in aging contribute to the pathogenesis of frailty. Epigenetic changes are among the factors that influence gene expression. It plays a role in regulating the immune system during aging, especially DNA methylation. DNA methylation profiles in the elderly have been widely studied. However, the differences in methylation patterns between robust and frail aging populations remain underexplored. A total of 32 subjects were recruited (age ≥ 65 years old) , consisting of 16 as the frail group and 16 as the robust group. For further methylation sequencing, only one robust subject and four frail subjects were selected. The selection of these individuals was based on their TNF-α concentrations, representing one subject with the lowest and four with the highest TNF-α levels. In this study, we identified an association between altered DNA methylation patterns, mRNA expression levels, and inflammatory conditions in frail elderly. The differential expression of certain genes is likely influenced by differences in methylation level between the frail and robust groups. In overall methylation, the differential of 5mC was slightly significant (p=0.06), while 5hmC was not significantly different (p=0.53). We aim to investigate these differences to gain a deeper understanding of the pathogenesis of frailty in some specific genes.
Project description:Illumina Infinium EPIC HumanMethylation BeadChip data from saliva DNA samples from a healthy elderly cohort with individuals in the age range 70-95 in Southwest Sweden. The cohort was stratified into study groups based on participants´answers to a questionnaire of different lifestyle factors including vitamin supplementations, smoking and drinking habits, physical activity (per year), sun exposure and eating habits. Vitamin D intake was evaluated from the vitamin D supplementation (alone or in a multivitamin complex), dietary vitamin D intake (fish and seafood frequency) and vitamin D synthesis in the skin (sunlight exposure and use of sunscreen). Differential methylation analysis was performed for all the study groups and the combination of different factors with vitamin D supplementation. Gender, age, smoking and alcohol (SD and frequency) were used as covariates in the analyses. Only the study groups referred to the conclusions of the study are shown.
Project description:Blood from elderly individuals exhibits a reduced "rejuvenating" effect compared to that of young donors, and plasma from older subjects used as a supplement in cell culture media is less effective than plasma from younger individuals. A mass spectrometry-based proteomic analysis of plasma samples from 229 blood donors—including a prepubertal group, a healthy young adult group, and a cohort of individuals over 75 years old—revealed a chronic inflammatory state in the elderly population, along with complement activation and negative regulation of blood coagulation. This inflammatory condition was confirmed by elevated levels of classical pro-inflammatory cytokines in the plasma of older individuals, as measured by microarray and Milliplex Luminex assays. Moreover, the elderly group showed a reduced production of antibody light chains, suggesting concurrent immunosenescence. We identified 25 proteins whose increased abundance, together with acquired immune aging, may constitute a plasma proteomic signature of aging. The degree of upregulation of these proteins varied among elderly subgroups with different lifestyles. An evaluation of the expression patterns of the 25 consistently elevated proteins revealed distinct protein clusters with differential expression across three lifestyle-based subgroups. Notably, a lifestyle aimed at preserving good physical and/or cognitive function appeared to attenuate the intensity of the aging-related proteomic signature. To explore potential gender-related differences in plasma protein expression, we compared samples from male and female donors. Among elderly individuals, no major differences were observed, except for an increased level of Pregnancy Zone Protein (PZP) in females. In contrast, several gender-specific differences were identified in the plasma profiles of young donors.
Project description:DNA methylation levels in whole blood measured over a ten years follow up in an elderly birth cohort of 86 samples For each sample, whole blood was drawn in year 1997 and in year 2007 Follow-up design: Same participant was measured over time in 1997 and 2007
Project description:The data contains Illumina 450k/EPIC array methylation files from 104 patients of the NOA-08 study comparing temozolomide alone vs. radiotherapy in elderly patients with glioblastoma