Squirrels to the rescue of astronauts
How squirrels hibernate without losing muscle mass could be useful for astronauts. This is according to a study, published Thursday in the journal Science, led by Matthew Regan, a biologist from the University of Montreal (UdeM).
Astronauts going into space face a common problem: declining muscle health. It’s the microgravity present in space that is at the root of this muscular weakening. Microgravity suppresses the muscle protein manufacturing process, causing muscle wasting.
Based on the metabolic process of squirrels, Matthew and his team propose a possible solution to this problem.
It’s because squirrels are able to naturally make new tissue proteins throughout their hibernation phase. Thus, they do not suffer any negative effects on their muscles, even after their prolonged inactivity.
By finding a way to replicate this process in humans, astronauts could have much better muscle health during long space travels.
The Squirrels Metabolic Trick
When squirrels hibernate, their gut microbes recycle nitrogen from the urea, a waste product normally excreted in urine, and use it to make tissue proteins.
“Because we know which muscle proteins are suppressed during spaceflight, we can compare these proteins with those that are boosted by urea nitrogen recovery during hibernation,” explains Matthew Regan.
In their study, Matthew and his team designed a series of experiments to try to understand the steps in the metabolic process of squirrels. This process is present in particular in the thirteen-lined ground squirrel, a common species in North America.
The mechanisms that mammals like the 13-lined squirrel have naturally evolved to maintain protein balance in their own nitrogen limitation can serve as the basis for strategies to maximize the health of other nitrogen-limited animals, including humans.
A discovery to help vulnerable people
Beyond the health of astronauts, this discovery could also help other people. Hundreds of millions of people around the world experience muscle weakness. This is particularly the case for undernourished people in developing countries and the elderly.
One solution could be a pill that people could take to promote a gut microbiome like that of squirrels .
“These applications, while theoretically possible, are however not yet forthcoming, and much work will be required to translate this naturally evolved mechanism in a way that is safe and effective for humans” , emphasizes Matthew Regan.
The young researcher continues to pursue his studies thanks to a grant from the Canadian Space Agency. He also holds the position of assistant professor in animal physiology at UdeM.