Proposing a Model for the Epigenetic Contribution to Aging

Is epigenetic change a cause or consequence of aging, and are epigenetic clocks measuring a cause or consequence of aging? In today's open access preprint, researchers build a model of the epigenetic contribution to aging, and propose that the answer is "both", with different epigenetic marks on the genome being either cause or consequence of aging. Epigenetic marks such as DNA methylation, the attachment of methyl groups to the genome at specific locations called CpG sites, alter gene expression. They do so by altering the structure of packaged DNA, either hiding regions from transcriptional machinery or exposing those same regions to allow RNA to be produced. The activity of RNA and proteins in a cell in turn alters epigenetic marks, a feedback loop that integrates contributions of the epigenome, cell machinery, and the impact of the surrounding extracellular environment. A cell is thus a dynamic system, but nonetheless the advent of epigenetic clocks has demonstrated that certain epigenetic marks are characteristic of aging. Why is this the case? It was widely thought that the epigenome reacted to the accumulating damage and dysfunction of aging, and thus was much more a downstream consequence than an important contributing cause of aging. In recent years, however, new studies have suggested that at least some epigenetic change may be closer to the fundamental causes of aging. For example, recall the research indicating that repeated cycles of DNA double stra...
Source: Fight Aging! - Category: Research Authors: Tags: Medicine, Biotech, Research Source Type: blogs