Hibernation slows epigenetic ageing in yellow-bellied marmots.
Level 5 - mechanism / opinion, no new human data
Level 5 by design analogy: observational/longitudinal study in a non-human animal population.
PubMed 35256811 · doi:10.1038/s41559-022-01679-1
What was done
Researchers tested the hibernation-ageing hypothesis in a wild population of yellow-bellied marmots (*Marmota flaviventer*), which hibernate for 7–8 months annually. Epigenetic age was estimated across 149 longitudinal samples from 73 females using both an epigenetic clock and an epigenetic pacemaker model. Age trajectories and seasonal fluctuations were analyzed via generalized additive mixed models (GAMM) incorporating chronological age and seasonal cycles as splines.
What was found
The abstract does not provide exact numerical effect sizes or p-values. Epigenetic age followed a logarithmic curve over lifespan, rising rapidly until sexual maturity at two years of age. Seasonally, epigenetic aging advanced during the active months and essentially stalled during the hibernation period.
Why it matters
The study offers molecular support for the hypothesis that metabolic depression during hibernation suspends biological aging, helping explain why hibernating mammals often live longer than predicted by body mass.
Limits
The study was restricted to female marmots from a single wild population, limiting direct generalizability across sexes or to other hibernators. The abstract omits precise quantitative estimates, confidence intervals, and effect magnitudes. Because the design is observational, specific mechanistic drivers of the seasonal epigenetic pause remain to be experimentally established.
Cited by
- supports A UCLA study on marmots during hibernation found that DNA methylation clocks did not advance while the animals hibernated.