Exhaustion From Sleep Deprivation: Molecular Clues Discovered In Worms

It's no secret that a night of not-enough-sleep makes us feel tired, stressed and all-around grumpy the next day. And now, researchers have found a molecular reason for why our bodies need to "make up" for that lost sleep -- at least, in worms.

The findings, published in the journal Current Biology, were conducted in nematode round worms called Caenorhabditis elegans (C. elegans). Even though the worm is an invertebrate, many scientists study these animals because observations in these creatures often apply to vertebrate animals, like humans.

Researchers examined the worms as they were in a developmental state of "lethargus" -- basically the worm equivalent of sleep, since worms don't sleep like humans do. They manipulated the worms so that they were unable to get any "sleep" during this phase. Researchers found that when the worms were "sleep"-deprived, a specific protein then activated genes known to play a role in stress. Scientists tried "knocking out" this gene, and found that when they did so, the worms no longer needed to make up for the exhaustion felt after being "sleep"-deprived (a concept called sleep homeostasis).

But researchers noted that while this may seem like a good thing -- hey look, no consequences of sleep deprivation! -- up to half of the worms whose genes were manipulated ended up dying.

"There's something important about being able to mount a homeostatic behavioral response," study researcher Dr. David Raizen, M.D., Ph.D., who is an assistant professor of neurology at the University of Pennsylvania, said in a statement. "We don't know what that is, but it's clearly important to the animal."

For more potential effects of sleep deprivation, click through the slideshow: