Scientists are unraveling the complicated relationship between food and sleep by studying a single molecular function in fruit flies.
In the October issue of the journal Neuron, researchers report that sNPF, a neuropeptide long known to regulate food intake and metabolism, is also an important component in regulating and promoting sleep.
When researchers, led by Leslie Griffith, professor of biology at Brandeis University, activated the neuropeptide sNPF in fruit flies, the insects fell asleep almost immediately, awaking only long enough to eat before nodding off again. sNPF also is known to regulate food intake and metabolism.
The flies were so sleepy that once they found a food source, they slept right on top of it for days—like falling asleep on a giant hamburger bun and waking up long enough to take a few nibbles before falling back to sleep.
When sNPF functions were returned to normal, the flies resumed their normal level of activity, leaving behind their couch potato ways.
The findings show that sNPF has an important regulatory function in sleep in addition to its previously known function coordinating behaviors such as eating and metabolism.
“This paper provides a nice bridge between feeding behavior and sleep behavior with just a single molecule,” says Nathan Donelson, a postdoctoral fellow in Griffith’s lab and one of the study’s lead authors.
Tying it all together
Neurons use neuropeptides to communicate a range of brain functions, including learning, metabolism, memory, and social behaviors. In humans, neuropeptide Y functions similarly to sNPF and has been studied as a possible drug target for obesity treatment.
But scientists don’t fully understand how regulating neuropeptide function at specific times and in specific cells affects sleeping and eating.
Studying sNPF in fruit flies might help explain which cells, neurotransmitters, and genes are involved in eating and sleeping; what processes turn on and inhibit the behaviors, and how sleep cells are relevant to hunger drive.
“Our paper makes a significant step into tying all these things together,” says Donelson, “and that is extremely important down the road to our understanding of human health.”
Source: Brandeis University