What Squirrels Can Teach Astronauts
What would you say if you had to fast for a whole season? It sounds like an impossible challenge for humans, but ground squirrels, however, achieve this very successfully every winter. A new discovery has revealed why, and the finding can really help astronauts with their physical health during long missions, news network The Conversation reveals.
A groundbreaking discovery
Long periods of inactivity are known to lead to muscle wastage in most animal species. But for hibernating animals, it transpires that things happen in a different way. Not only can they survive without eating, but they also use minimal levels of energy while preserving their muscle mass and function during and after the whole winter, the official information channel at the University of Montreal, Udeme Nouvelles, explains.
It was Matthew Regan, an animal physiologist from the University of Montreal, who discovered why. In his research published in Science, he confirms a theory from the 1980s called “urea nitrogen salvage” through the study of the 13-lined ground squirrel, a common species from North America.
According to the theory, the gut microbes from these cute hibernators have a very special ability. They can recycle the nitrogen present in urea and reuse it to build new proteins. In short, they can take advantage of waste that is otherwise excreted as urine, and turn it into something vital.
“By facilitating muscle protein synthesis late in the hibernation season, urea nitrogen salvage may help optimize the emerging squirrels’ muscle function and contribute to their reproductive success during the mating season,” Regan told Udeme Nouvelles. This way, when squirrels emerge from hibernation, they are in good shape to cope with the intense physical activity that a successful reproduction demands.
Why astronauts may benefit
Regan’s findings could have a meaningful impact on the future of space travel, considering that crew members tend to experience muscle atrophy because of a microgravity-induced suppression of muscle protein synthesis, The Conversation points out.
According to the researcher, if astronauts manage to replicate the salvaging of urea nitrogen, they will be able to prevent muscle loss, a common issue among space travelers. Although they already try to avoid this by following intense exercise routines, these are not always enough. Not to mention that long space trips on a small spacecraft can make exercising a real challenge.
“Because we know which muscle proteins are suppressed during spaceflight, we can compare these proteins with those that are enhanced by urea nitrogen salvage during hibernation,” Regan told Udeme Nouvelles. “If,” the researcher continued, “there is an overlap between the proteins in spaceflight and the ones from hibernation, then it suggests this process may have benefits to muscle health during spaceflight.”
Other promising applications
It is not only astronauts that could benefit from this astonishing discovery. Avoiding muscle wastage could also help people in other situations, such as the elderly or those suffering from undernourishment. Both groups tend to face muscle mass loss, and therefore, the loss of body strength.
Regan states that there’s still a lot of work to do to make these applications safe and effective for humans. However, this might be possible in the future. “One thing I find encouraging is that a study from the early 1990s provided some evidence that humans are capable of recycling small amounts of urea nitrogen via this same process. This suggests that the necessary machinery is in place. It just needs to be optimized.”
Once again, we can see how nature brings us closer to the answers we need in order to face the most diverse challenges. We just have to learn from her and imitate her coping mechanisms. The rest will fall into place.
