The commonest bat in the USA, the massive brown bat, boasts an unusually lengthy lifespan of as much as 19 years. A brand new research led by College of Maryland researchers identifies one of many secrets and techniques to this bat’s distinctive longevity: hibernation.
“Hibernation has allowed bats, and presumably different animals, to remain in northerly or very southerly areas the place there is not any meals within the winter,” stated the research’s senior creator, UMD Biology Professor Gerald Wilkinson. “Hibernators are likely to outlast migrators. We knew that, however we did not know if we might detect modifications in epigenetic age on account of hibernation.”
The researchers decided that hibernating over one winter extends a giant brown bat’s epigenetic clock — a organic marker of growing old — by three-quarters of a yr. The research, printed within the journal Proceedings of the Royal Society BonAugust 10, 2022, additionally included scientists from McMaster College and the College of Waterloo, each in Ontario, Canada.
They analyzed small tissue samples taken from the wings of 20 large brown bats (Eptesicus fuscus) throughout two intervals: within the winter once they hibernated and in the summertime once they had been energetic. The bats, saved in a analysis colony at McMaster College, ranged in age from lower than 1 yr previous to a bit of over 10 years previous.
As soon as the samples had been collected, the researchers measured modifications in DNA methylation — a organic course of related to gene regulation — between samples taken from the identical animal throughout energetic and hibernating intervals. They found that modifications in DNA methylation occurred at sure websites within the bat’s genome, and these websites seemed to be affecting metabolism throughout hibernation.
“It is fairly clear that the websites that lower methylation within the winter are those that seem like having an energetic impact,” Wilkinson stated. “Most of the genes which can be nearest to them are identified to be concerned in regulating metabolism, so that they presumably hold metabolism down.”
A few of these genes are the identical ones that Wilkinson and fellow researchers recognized as “longevity genes” in a earlier research. Wilkinson stated that there’s important overlap between the hibernation genes and the longevity genes, additional highlighting the hyperlink between hibernation and longer lifespans.
The sooner research additionally established the primary epigenetic clock for bats, able to precisely predicting the age of any bat within the wild. That clock was utilized to this newest research, enabling the researchers to reveal that hibernation reduces a bat’s epigenetic age compared to a non-hibernating animal of the identical age.
Research like this assist clarify why bats have longer lifespans than anticipated for a small mammal concerning the measurement of a mouse. Nevertheless, additionally they elevate new questions.
“We nonetheless do not have an excellent understanding of why some bats can dwell a very very long time and different ones do not,” Wilkinson stated. “We have proven that those that dwell a very very long time all share the power to hibernate, or to enter torpor ceaselessly. That appears to be a corollary, nevertheless it’s not adequate as a result of hibernating rodents do not dwell 20 years.”
Wilkinson stated he’s planning a follow-up research to check epigenetic growing old in large brown bats in Canada, the place they hibernate, with the identical species in Florida, the place they don’t hibernate. In doing so, Wilkinson hopes to get a fair clearer image of the function that hibernation performs in prolonging lifespans.