Brown’s Cutting-Edge Research: What Worms Tell Us About Sleep

Wednesday, May 25, 2011

Maggie Lange, GoLocalProv Contributor

The early bird catches the worm presumably praises early risers—but has darker implications if you think about the consequences of the worm’s sleep cycle.

A study at Brown University has just focused on worms' sleeping patterns and made a profound discovery (which has little to do with whether their hour of waking will make them more or less likely to be prey).

While observing C.elegans nematodes, a group of Brown neurobiologists made an unexpected observation that lead to a serious breakthrough in understanding the neurobiology of sleep in a wide variety of animals, including humans. They discovered that “Notch,” a fundamental signaling pathway present in all animals, is directly involved in the sleep of these worms.

This research was published by the journal Current Biology and provides important insights into what controls sleep. Anne Hart, the senior author of the study, said that sleep is still a huge mystery to scientists: “Since we don’t know what makes us sleep, we need to understand what parts of the brain are important and what signals the brain to sleep.”

Tiny specimens

Worms are ideal subjects to help scientists learn more about sleeping patterns of larger mammals, said Hart. “We should figure it out, where it’s simpler first," she said. "This will help us figure out what’s going on in larger brains like ours.”

Even though these worms are about a millimeter big, the nematodes share sleeping patterns with humans. “We do know they are exhausted after exercise and after a big meal,” said Hart, laughing about humans' so-called ‘food comas.’ “The parallels were striking.”

Additionally, their size makes them ideal subjects for a large-scale research. “They are really small, easy to work with,” she said. “We can get things done a lot faster and less expensively in worms, and there are basic similarities with humans.”

Unexpected discoveries while napping

The focus on sleep in nematodes actually came about quite by accident. Hart first noticed that Notch pathway genes might be involved in sleep patterns while studying a different behavior of these worms: their reaction to an odious substance called octanol.

When faced with this smelly substance, the worms should have wiggled vigorously to escape it, but instead they would pause and take “mysterious naps,” for a few minutes, and then wake up and beginning wiggling again. “It’s the strangest thing I’ve seen in over a decade working with worms,” said Hart.

Soon it became clear; as Notch signaling was “turned on” the sleepier worms would be. When it was suppressed, they would go into overdrive and wiggle vehemently—with twice as many ‘body bends’ each minute as would be normal.

Better sleep at night?

By understanding how sleep is signaled in these worms, this research could be used to develop more precise and safer sleep aids. Researchers can begin to start targeting this pathway in people as well, but Hart cautioned, “You don’t want to tweak it too much because if goes out of control in other parts of the body you can get cancer.”

“I would not immediately run and out and come up with a drug treatment based on our research,” she said.

However, this breakthrough in understanding how sleep is signaled in this simple animal has made a serious breakthrough into our understanding in the enigma of how all animals sleep.