Epigenetic Change with Age in Mice is Not Linear
Epigenetic marks, like DNA methylation, play a crucial role in controlling gene expression and cell behavior. As organisms age, these marks change, reflecting the processes of damage and dysfunction that come with aging. Researchers studying DNA methylation in mice have found that these age-related changes are not linear, progressing in stages and phase transitions. Understanding this non-linear progression is important when considering the use of epigenetic clocks to measure biological age and assess potential rejuvenation therapies.
By analyzing aging mouse colon tissues, researchers identified sets of CpG sites that undergo sudden methylation changes at two distinct time points. One set experiences rapid methylation changes during the transition from early to midlife, while another set shows accelerated changes from mid to late life. Interestingly, similar methylation switches were observed in rat peripheral blood DNA, supporting the division of lifespan into three stages. This data aligns with the digital aging hypothesis, which posits aging as a series of discrete steps with varying mechanisms that influence progression rates over the lifespan. The presence of transitions between these stages suggests a more controlled or programmed nature of epigenetic aging, posing questions about regulation and consequences of these abrupt changes and highlighting the importance of studying multiple age points for a comprehensive understanding of aging.
Link: https://doi.org/10.1038/s41467-024-47316-2
