If the unique adaptations of bat blood can be exploited during hibernation, astronauts could survive a decades-long flight to another star in the universe.
Nyctalus noctula is one of the hibernating bat species. Image: EUNIS
One potential solution for space travel is hibernation because scientists believe this could help astronauts endure long interstellar flights. NASA has been exploring that idea for years, even studying the hibernation patterns of Arctic ground squirrels. However, research published in the journal Proceedings of the National Academy of Sciences by a group of German experts, led by Gerald Kerth at the University of Greifswald, focused on bats to explore the ability to hibernate effectively, Interesting Engineering reported on November 27.
Kerth and his colleagues studied the role of erythrocyte, a special type of red blood cell, during hibernation. They conducted a general analysis with erythrocyte taken from hibernating bats (Nyctalus noctula) and bats do not hibernate (Rousettus aegypticus), as well as human blood specimens. Understanding how these blood cells regulate during hibernation is important, because hibernating animals still need to transport oxygen to their tissues even when their body temperature drops significantly.
The team found that blood cells change shape in response to changes in pressure and blood vessel size. This prompted them to investigate whether extreme conditions during hibernation could trigger changes in blood cells. As a result, they found that when the internal temperature of the hibernating species decreased from 37.2 to about 22.8 degrees Celsius, the erythrocyte structure of all the species examined had a major change. Cells become less elastic and more viscous, revealing physiological adaptations to conserve energy in cold conditions.
The study also revealed a key difference. While bat erythrocyte continues to mutate at temperatures down to 10 degrees Celsius, human blood cells’ response slows down. The findings demonstrate that bats possess unique adaptations that allow them to endure extreme cold environments, a trait that could be exploited for potential applications in humans.
Hibernation is a key biological strategy for many mammals, allowing them to conserve energy and survive in the face of scarce resources. If humans wanted to travel to nearby stars like Proxima Centauri, which is 4.24 light-years away, even at speeds close to the speed of light, the trip could take decades. Therefore, hibernation may be necessary for future space missions.
While applying hibernation to space travel is a long-term goal, the research results could revolutionize medicine. Scientists believe that understanding how to control the mechanical properties of red blood cells helps optimize the circulation of pharmaceuticals.