Wisdom Of The Week

You've probably never heard of the fat-tailed dwarf lemur, a nocturnal primate (native to Madagascar) that hops around in trees and is about the size of a rat. But these little guys are pretty closely related to humans—relative to most other life on Earth, anyway—and they are able to do something quite extraordinary. Like bears, marmots, and bats—but unlike any other primates—they hibernate (or, as some researchers put it, enter into a prolonged "period of increased torpor") during Madagascar's winter season. For as much as half the year, they huddle together, dramatically slow their metabolism, and (hence the name) live off of their plentiful tail fat.

This primate species, explains University of Pennsylvania professor of medicine David Casarett, may provide a roadmap for how humans themselves might someday enter a hibernationlike state. After all, despite the dramatic differences between us, we share 97 percent of our DNA with this tiny (and super cute) mammal, according to one Duke University lemur expert. "There's hope out there, maybe, for a wonder drug, a simple injection that will reduce somebody's metabolism by 99 percent, and put victims in a state of suspended animation," says Casarett, author of the new book Shocked: Adventures in Bringing Back the Recently Dead.

Why would anyone want to enter a state of suspended animation? Hibernation is characterized by a slower metabolism, a decreased heart rate, slower breathing, and much colder body temperatures. And while there are several reasons why a person might want to go there, perhaps the most common one involves staving off death. People who have just been shot or injured in a car wreck, or who are having a heart attack, all share one danger: Vital organs, like the brain, are easily damaged after going just a few minutes without receiving sufficient oxygen from their bloodstream.

More and more evidence suggests that traditional practices of resuscitation, which may include keeping the body warm and trying to kick-start the heart (using hormones like epinephrine), can sometimes do more harm than good. Warm body temperatures and a quickly beating heart keep the organs of the body functioning at top speed, using up oxygen and other nutrients in the bloodstream. After as few as four minutes without oxygen, say from a heart attack, brain damage can set in.

So maybe we should consider putting away the epinephrine and instead encourage the body to cool down and slow its metabolism, as in hibernation, so that the organs most in danger of being irreparably harmed require less energy, and therefore less oxygen, to survive. "By cooling cells, you decrease their metabolism," Casarett says. "You decrease the rate at which they use some of the building blocks of energy…cells also reduce the rate at which they use oxygen. And so by reducing the metabolic rate of those cells, [you] can essentially trick the body into thinking that it's in a state of hibernation." Casarett says that this technique holds the potential to stave off brain damage for 20 or 30 minutes—maybe even an hour.

- Will Humans Ever Learn to Hibernate? brilliant piece based on David Casarett's new book Shocked: Adventures in Bringing Back the Recently Dead