How modifying red blood cells can enable humans to hibernate like bats

Bats change their red blood cells during hibernation, making them thicker and harder. If we can figure out how, humans may one day be able to mimic the process for medical treatments and long-distance space travel.

Animals hibernate to conserve energy during cold weather or when food is scarce, their heart rate slows and their body temperature drops to 5°C (41°F), entering a state known as torpor. This is only survivable if blood continues to flow efficiently and oxygenate the body, but until now scientists do not fully understand how this happens.

we already know that The shape of red blood cells changes To accommodate different pressures and vessel sizes, Gerald Kurth Researchers at the University of Greifswald in Germany thought that cells in hibernating bats might change shape to preserve blood flow in the cold.

To investigate, the team analyzed hundreds of thousands of red blood cells from the common nocturnal bat (noctiluca), hibernating fruit bats (Aedes aegypti), those that do not hibernate, and those from people.

The researchers found that in all three species, red blood cells became less elastic and more viscous as temperature decreased from 37°C to 23°C (99°F to 73°F). However, when the cells were further cooled to 10°C (50°F), the bat cells continued this metamorphosis, while the human cells did not.

In fact, bat cells continued to thicken, stiffen, and function even at very low temperatures, even in non-hibernating bat cells, which likely retained their evolutionary potential. This change may cause cells to move more slowly through capillaries in muscles and lungs, making them more efficient at exchanging gases such as oxygen throughout the body.

“If you take your time shopping instead of rushing at the supermarket, you'll really fill up your shopping cart,” says Kurth. Exactly how this structural change occurs is still unclear, but the researchers suspect that the mechanical properties of the bat's red blood cell membranes play an important role.

The findings suggest that drugs could one day induce human red blood cell membranes to mimic the response of cell membranes to cold in bats, Kaas said. Surgeons already use body cooling during certain procedures to Can slow down metabolism and prevent organ damage For those experiencing a heart attack, organ transplant, or major brain surgery. Extending the cooling time or lowering the temperature further could further increase these benefits, team members say. Carsten Scholzalso at the University of Greifswald.

In the more distant future, hibernation may allow us to: Efficient long-distance space travel Food and other resources needed are kept to a minimum while maintaining mental health while traveling. “There are advantages to keeping humans at low temperatures during interstellar flight,” Kaas says. “I'm not saying this is going to happen in the next three years. But it's really a first step.”

The study shows that learning how other mammals adapt to extreme environments could benefit humans, it says. Angelo D'Alessandro At the University of Colorado Anschutz. “Nature has many undiscovered secrets that can teach us how to overcome current and future medical and technological challenges.”