One night of sleep loss alters clock gene expression
21 Aug 2015 by Evoluted New Media
Gene expression that control biological clocks in cells throughout the body is altered after losing a single night of sleep suggests new research at Uppsala University.
By using molecular analysis of tissues samples, it was discovered that the regulation and activity of clock genes was altered after one night of sleep deprivation.
“Previous research has shown that our metabolism is negatively affected by sleep loss, and sleep loss has been linked to an increased risk of obesity and type 2 diabetes. Since ablation of clock genes in animals can cause these disease states, our current results indicate that changes of our clock genes may be linked to such negative effects caused by sleep loss”, said research leader Dr Jonathan Cedernaes.
In the study, published in the Journal of Clinical Endocrinology and Metabolism, the team studied 15 healthy normal-weight men over two 2-night sessions. In one of the two sessions the participants slept over 8 hours, while they were kept awake in the other.
Following the second night on both occasions, the scientists collected samples from the two kinds of tissues that are important for regulating metabolism and controlling blood sugar levels – the superficial fat on the stomach and the muscle on the thigh. They also collected blood samples before and after the participants had consumed a sugar solution to test their insulin sensitivity.
Results from the molecular analysis of the collected tissue samples showed that the regulation and activity of clock genes was altered after one night of sleep loss. The samples taken from sleep-deprived participants showed increased evidence of epigenetic activity – l alterations of the molecules that regulate which genes are switched on or off – and a change in the level of gene expression being processed.
Dr Cedernaes said: “As far as we know, we are the first to directly show that epigenetic changes can occur after sleep loss in humans, but also in these important tissues. It was interesting that the methylation of these genes could be altered so quickly, and that it could occur for these metabolically important clock genes.”
The scientists hope their findings will allow them to investigate how long the gene alteration lasts for and assess the risks of metabolic diseases.
“This could suggest that these important molecular clocks are no longer synchronised between these two tissues. As such, ‘clock desynchrony’ between tissues has been linked to metabolic pathologies, this could suggest that these tissue-specific changes were linked to the impaired glucose tolerance that our participants demonstrated after the night that they had been kept awake,” added Dr Cedernaes.
