MentallyHealth.Org

Research on fruit flies suggest starvation allows sleep deprivation

May 27, 2017

Shaw's lab previously demonstrated that fruit flies with a mutation in a timekeeping gene accumulate sleep debt much more quickly and begin dying after being kept awake for as little as 10 hours. Matt Thimgan, PhD, a postdoctoral research associate, reports in the new paper that starving fruit flies spent more time awake, and starving fruit flies with the timekeeping gene mutation could survive up to 28 hours without sleep.

Scientists tested the starving, sleepless flies for two markers of sleep debt: an enzyme in saliva and the flies' ability to learn to associate a light with an unpleasant stimulus. Both tests showed that the starving flies were not getting sleepy.

"From an evolutionary perspective, this makes sense," Thimgan says. "If you're starving, you want to make sure you're on the top of your game cognitively, to improve your chances of finding food rather than becoming food for someone else."

Scientists found an effect similar to starvation in fruit flies where a gene called Lipid storage droplet 2 (LSD2) was disabled. After sleep deprivation, flies with the LSD2 mutation were less likely to sleep for longer periods of time and continued to score high on the learning test.

"LSD2 mutants seem to constantly rotate lipids through their storage depot in cells, putting them in and moving them out very quickly," Thimgan says. "Disabling LSD2 appears to make it hard for cells to hold on to lipids and use them properly, and we think this impairs brain cells' ability to respond to sleep deprivation."

Researchers are working to identify the specific lipids affected by loss of LSD2.

Source: Washington University School of Medicine