Research Into Bear Hibernation Could Lead to New Diabetes Treatments
Michelle Milliken
The hibernation period for bears sees their bodies do some pretty interesting things. Their temperatures are lowered 8-12 degrees, they break down fat stores for energy, and they rarely defecate or urinate during those months. They also have different insulin regulation. During hibernation, they’re insulin resistant, while they’re insulin sensitive the rest of the year. Researchers at Washington State University are looking into how this function could help humans with diabetes.
Washington State University evolutionary biologist Joanna Kelley received a $40,000 grant to study how eight bear proteins involved in the process help reverse insulin resistance and obesity. The findings could then be applied to humans.
Kelley says, “They make this natural metabolic transition every spring and every fall without any negative health consequences, and we are trying to figure out how are they able to do that. The really big goal is finding a solution to diabetes in humans.”
At WSU’s Bear Research, Education and Conservation Center, scientists regularly weigh the animals, draw blood samples, and provide special diets. By comparing blood serum samples from active and hibernating bears, Kelley discovered eight proteins that are similar to those found in humans and may play a role in insulin resistance in bears.
When blood serum from an active bear was applied to cells from a hibernating bear, there were changes in the cells associated with insulin sensitivity. The goal now is to find out which proteins or combination of proteins change metabolic states. Kelley will use a new cell culture model created by WSU College of Veterinary Medicine professor Heiko Jansen for the test.
Kelley says, “We hope to uncover the first verifiable molecular and cellular mechanisms into hibernation. This fundamental discovery will have a long-lasting impact on our understanding of basic metabolic processes conserved across humans and animals.”
Jansen explains that bears have circadian rhythms, just like humans. This is still the case when they’re hibernating because they aren’t sleeping the whole time. They still manage a consistent waking/sleeping cycle. Disruptions in circadian rhythms can make animals more prone to metabolic diseases. This could play a role in why bears avoid diabetes.
Jansen explains, “Having a viable circadian clock, even during hibernation, was perhaps one way to protect yourself from the negative effects of insulin resistance.”
With the findings from her hibernation study, Kelley hopes that a potential diabetes treatment won’t be the only thing uncovered. She could also see the research providing more insight into obesity, heart disease, stroke, and cancer. It could even, in the future, help with induced hibernation for complex surgeries or space travel to habitable exoplanets.
For a months-long stretch of minimal activity in bears, that's a lot of potential.
