FLICKR, JULIE VACCALLUZZO
Certain compounds involved in metabolism are measurably depleted in the blood of people and rats that are sleep deprived, according study published in PNAS this week (February 9). Researchers from the University of Pennsylvania Perelman School of Medicine and their colleagues detected changes in several metabolites in the blood of rats and humans that slept only four hours a night for five nights, with two of these metabolites—oxalic acid, which is a byproduct of normal metabolism, and diacylglycerol 36:3, which plays a role in energy storage—dropping precipitously in both species.
The findings could help researchers develop a simple blood test for severe sleep deprivation that could be useful for making sure that pilots, long-haul truckers, and others whose jobs require alertness are sufficiently rested. The results may also shed light on the molecular mechanisms underlying the effects of sleep loss, a poorly understood area of physiology. Study coauthor Amita Sehgal, a neuroscientist at the University of Pennsylvania, and her colleagues intend to follow up on the study. “We’re seeing these changes in the blood, but where are they coming from and how do they relate to what’s happening in the liver, the adipose [fatty] tissue, the muscle?” Sehgal told Science News.