No replies to this topic

[reason]

Researchers here report on the differences in epigenetic aging between mice kept in standard laboratory facilities versus mice allowed to roam a more natural habitat with minimal supervision. The laboratory mice aged more slowly, which one might theorize has to do with greater degrees of care and attention from the laboratory staff. However, the researchers argue that the natural habitat imposes greater stresses upon the mice in various ways, and that in turn accelerates the epigenetic changes characteristic of aging.

We examined differences in age-associated methylation changes between traditionally laboratory-reared mice and "rewilded" C57BL/6J mice, which lived in an outdoor field environment with enhanced ecological realism. Our results lead us to two conclusions. First, the rate of epigenetic changes in the most used biomedical model organism is highly dependent on environmental context, with laboratory-reared animals showing a global bias toward slower rates of epigenetic aging compared to field-reared animals. Second, this more rapid aging of the epigenome is particularly pronounced in sites that gain methylation with age, which are enriched for genes associated with insulin regulation, DNA damage repair, and CTCF and cohesin binding. From the current data, it remains unclear if rewilded mice also show accelerated senescent phenotypes, including early onset disease development and behavioral declines, compared to those in the laboratory.

Our data hold some possible insights into the mechanisms by which animals may display accelerated epigenetic aging in the field compared to the laboratory. From an environmental perspective, animals in the field are exposed to a wide range of different environmental challenges and opportunities, including (1) social competition and potential resource scarcity in males, (2) homeostatic challenges resulting from dynamic weather experiences, (3) social instability when animals die or are born, and (4) reproductive effort in the form of mating and territorial defense in males and pregnancy and reproduction in females. Each of these environmental experiences - which are faced to an extent by all natural populations of vertebrates, including humans - may have contributed to short-term or chronic physiological stress, with downstream impacts on epigenetic aging rates.

Link: https://doi.org/10.1111/acel.70098

View the full article at FightAging