Increased Food Intake After Starvation Enhances Sleep in Drosophila

Abstract

Feeding and sleep are highly conserved, interconnected behaviors essential for survival. Starvation has been shown to suppress sleep across species; however, whether satiety promotes sleep is still unclear. In this study we use the fruit fly, Drosophila melanogaster as a model organism to address the interactions between feeding and sleep. We first monitored the sleep of flies that had been starved for 24 hours and found that sleep amount increased in the first four hours after flies were given food. Increased sleep after starvation was due to an increase in sleep bout number and average sleep bout length. Mutations in translin or adipokinetic hormone, which result in the failure to suppress sleep during starvation, did affect sleep increase after starvation. This suggests sleep increase after starvation is not a consequence of sleep loss during starvation. We also found that feeding activity and consumption is higher in the first 10-30 minutes after starvation. Restricting food consumption in starved flies to 30 minutes was sufficient to increase sleep for one hour. Although flies ingest a comparable amount of food at differing sucrose concentrations, increased sleep after starvation on a lower sucrose concentration was not detectable. Taken together, these results suggest increased food intake after starvation enhances sleep and reveals a novel relationship between feeding and sleep.