Amylase in Saliva Signals Sleepiness in Patient
Study in flies and humans suggests amylase activity marks level of sleep drive
FRIDAY, Dec. 15 (HealthDay News) -- The amount of amylase found in human saliva may be an indicator of an individual's level of sleepiness, according to a report published online Dec. 13 in the Proceedings of the National Academy of Sciences Early Edition.
Paul Shaw, Ph.D., of Washington University School of Medicine in St. Louis, and colleagues found that amylase expression accumulates in flies that have a mutation in a canonical clock gene and asked whether amylase activity may be an effective indicator of sleep drive.
In both flies and humans, amylase activity correlated with extended periods of waking and can be measured in real time in the fly. In five of nine human subjects exposed to 28 hours of continuous waking, amylase activity in their saliva increased by up to twofold compared with control subjects.
"These data indicate that the fly is relevant for human sleep research and represents a first step in developing an effective method for detecting sleepiness in vulnerable populations," the authors conclude.