Historic hibernation discovery may have unlocked long space travel

For many animals, life is a cycle of abundance as well as scarcity. Hibernating creatures curl up underground in winter, slowing their metabolism so they can go without food until spring. This is something people have long dreamed of: If we’re going to leave this planet and travel to space, we may need to go into hibernation. A new study in mice shows that this may be possible.

sci-fi come true

In science fiction, space crews are often spared the tedium and hassle of long-distance space travel by being put into a frozen state of sleep. This goal may be one step closer after scientists showed that hibernation in rodents can be artificially triggered using ultrasonic waves.

This improvement is considered important because it is effective in mice that do not naturally hibernate. This raises the possibility that humans may also have a vestigial hibernation cycle in their brains that can be reactivated artificially.

“If this proves viable in humans, we can imagine astronauts wearing a helmet-like device designed to trigger a state of hypothermia and hypometabolism by targeting the hypothalamus region,” said Hong Chen, an associate professor at the University of Washington who led the study.

In the study published in the journal Nature Metabolism, scientists revealed that they could put mice in a hibernation-like state by targeting a specific part of the brain with short-term ultrasound waves. While it’s not entirely clear why ultrasound has this effect, the findings suggest that studying neural circuits related to sleep may reveal ways to manipulate metabolism outside of the lab.

Mice fell into a deep sleep

Ultrasound devices that produce high-frequency sound waves are best known for their imaging capabilities, but these devices are also used by neuroscientists to stimulate neurons. Hong Chen, a professor of biomedical engineering at the University of Washington and one of the authors of the new paper, said that when sound waves are tuned correctly, they can go deep into the brain.

Curious about a brain region that regulates body temperature in rodents, Dr. Chen and colleagues built tiny ultrasound mouse heads. The devices directed six waves of 10 seconds of ultrasound each to the selected area of ​​the rodent brain. The researchers noticed that the mice stopped moving. Measurements of body temperature (by as much as 3 degrees), heart rate (dropped by 47 percent), and metabolism showed a marked decrease.

It may also work in humans

It was stated that the mice remained in this state for about an hour and then returned to normal. What’s more, the researchers had the mice kept in a hibernation-like state at 33C for 24 hours. When the ultrasound system was turned off, the mice woke up again. Dr. Chen said the result was “surprising and fascinating” and that the team plans to test the technique in larger animals.

Taking a closer look at the neurons that cause this response, the researchers identified a protein in the cerebral membranes called TRPM2, which appears to be ultrasound-sensitive; When the researchers lowered the protein levels in the mice, the mice became resistant to the effects of ultrasound. Scientists don’t know for sure if this technique will work in humans, but Prof Martin Jastroch of Stockholm University said the same technique would theoretically work in humans “it’s pretty high”.