A new study from the University of Alaska Fairbanks uncovers how Arctic Ground Squirrels recycle nutrients to stay healthy during their long hibernations. KUAC’s Mary Auld reports.
Sarah Rice is the lead author of the paper and a Ph.D. student at UAF’s Institute of Arctic Biology. She says during the winter, arctic ground squirrels enter a state of extreme hibernation.
"They can take their body temperature below freezing, when they're in hibernation their heartbeats five times a minute, and they breathe once a minute, they're just this incredible animal. It's almost like in a suspended state of animation. And how they do that, you know, some people discovered certain things with it, but we don't know exactly how it works completely."
Arctic ground squirrels can hibernate for up to eight months—and they appear to awake from their winter sleep without the impacts of starvation or muscle loss. Rice wanted to know how they stayed in such good shape without exercise or food.
The study found that the squirrels’ bodies transformed existing nutrients into resources that could be used to build back tissue that atrophied during hibernation.
To do the study Rice and her colleagues collected squirrels, brought them to a lab, and introduced them to the cold, dark conditions that induced hibernation. During hibernation the scientists sampled the animals’ blood to track how nutrients in their bodies changed over time.
"We go into this cold chamber with a little headlamp on that's the chamber start. And we run our experiments on the animal just going super slow, and super carefully, so we don't wake them up. And then we put them back on the shelf, and you're just in this dark room surrounded by like 30 hibernating animals the entire time. It's just dead quiet."
If humans were to stay in one very cold place without food or exercise, they wouldn’t be able to survive the starvation or muscle atrophy that would occur. If they could recycle nutrients like Arctic Ground Squirrels do to stay healthy during hibernation, it could keep people on bed-rest from losing muscle or allow astronauts to travel to space with fewer resources. According to Rice, researchers think they may be able to borrow some of the science of hibernation for use in human medicine.
"Hibernation is a model that has found solutions to problems in the world. It's able to survive extremely long, fast at extremely cold temperatures. And so if we can understand some of these mechanisms of resilience, maybe we can take that and apply it to human medicine."