Bears do it. So do groundhogs, squirrels, turtles, and many other animals. Humans, however, can’t hibernate at least not right now. But scientists exploring the genetic underpinnings of hibernation in animals think they may be able to unlock the same biological superpower in humans.
That feat could transform medical care during both routine surgeries and dire medical emergencies when patients cannot immediately get access to lifesaving treatment. It could also make it possible for astronauts to snooze their way on long missions to Mars and other destinations in deep space.
The scientists think the ability to hibernate arose with the first ancestral mammal a furry, tree-dwelling creature that lived 65 million years ago and eventually gave rise to most modern mammals, including humans. If they’re right, the keys to hibernation may lie hidden in the human genome.
Hibernation is much more than extended sleep. It brings dramatic changes in metabolism, including a drop in body temperature and reductions in heart rate and breathing. Some warm-blooded animals spend weeks during which their body temperature falls from around 37 degrees Celsius to as low as 3 degrees Celsius, their hearts beat just a few times a minute, and the body’s energy consumption plummets.
Scientists are especially interested in the mechanisms that allow hibernating animals to return to full activity shortly after waking and avoid the health problems that affect humans after a few weeks in bed. These include bone loss, cardiovascular problems, and muscle wasting.
The applications we’re looking at come out of our understanding of what these animals have to do to survive hibernation throughout the year. Since at least 2002, emergency room doctors have been tapping into the protective power of hibernation by using ice packs and cooling blankets to temporarily lower the body temperature of patients who are critically ill as a result of heart attack, brain injury, stroke or shock.
Lowering body temperature by just a few degrees Celsius can protect the brain in particular by slowing metabolism, reducing swelling and delaying brain cell death that might normally occur due to lack of blood flow.
Decoding Hibernations Past For Future
To create that hibernation wonder drug, researchers must first discover which groups of genes are activated during the hibernation process. It is reaching out to many independent hibernation research groups to combine collections of biological tissue from different hibernator animals with new databases of sequenced genomes.
Even modern medicine's "targeted temperature management" approach that falls short of full hibernation could still protect astronauts and make future space missions both more affordable and feasible.
Putting most of the crew into a low-metabolism state on shifts could eliminate much of the spacecraft mass normally reserved for storing food supplies or having a larger living space.T he true awakening of hibernation powers in humans still relies upon the ancestor mammal theory being proven correct.
But if hibernating astronauts someday wake up to find themselves ready to enter Mars orbit, they can give thanks to a biological superpower that was millions of years in the making.