Loss of chromatin structural integrity is a source of stress during aging

Dysfunction and dysregulation at multiple levels, from organismal to molecular, are associated with the biological process of aging. In a eukaryotic nucleus, multiple lines of evidence have shown that the fundamental structure of chromatin is affected by aging. Not only euchromatic and heterochromatic regions shift locations, global changes, such as reduced levels of histones, have been reported for certain aged cell types and tissues. The physiological effects caused by such broad chromatin changes are complex and the cell's responses to it can be profound and in turn influence the aging process. In this review, we summarize recent findings on the interplay between chromatin architecture and aging with an emphasis on the cellular response to chromatin stress and its antagonistic effects on aging.