DNA Methylation Control over Aging: A Focus on Repetitive Elements

DNA methylation is an epigenetic modification that has been gaining particular attention among researchers in the field of aging and aging-related dis eases. Specific DNA methylation changes, indeed, characterize aged cells and potentially predict age and lifespan, suggesting that they may play a key role during the aging process. In particular, DNA demethylation of repetitive elements (RE) is a common observation in aging cells and correlates with the increase of transcrip tion of repeat-derived noncoding RNAs. Demethylation of satellites and loss of suppression of retrotransposons generate genome instability, can increase cell stress and affect cell viability, and also can impact the regulation of genes associated with cell-lineage specificity, thus contributing to neurodegeneration and susceptibility to cancer. In this chapter, we discuss recent work on the DNA methylation dynamics at RE during the aging process outlining the potential roles played during aging. A better understanding of these roles could help in the advancement of approaches to enhance healthy aging and of therapies for aging-related diseases.