University of Helsinki researchers have identified what kinds of biological mechanisms related to sleep loss affect the immune system and trigger an inflammatory response. They identified the genes that are most susceptible to sleep deprivation and examined whether these genes are involved in the regulation of the immune system. The results provide at least a partial explanation of why sleep deprivation increases the risk of cardiovascular disease and type 2 diabetes.
Conducted at the sleep laboratory of the Finnish Institute of Occupational Health, the study restricted the amount of sleep of a group of healthy young men to four hours per night for five days. Blood samples were taken before and after the sleep deprivation test. White blood cells were isolated from the samples, and the expression of all genes at the time of the sampling was examined using microarrays. The results were compared with samples from healthy men of comparable age who had been sleeping eight hours per night for the week.
“We compared the gene expression before and after the sleep deprivation period, and focused on the genes whose behaviour was most strongly altered,” says researcher Vilma Aho in a release. ”The expression of many genes and gene pathways related to the functions of the immune system was increased during the sleep deprivation. There was an increase in activity of B cells which are responsible for producing antigens that contribute to the body’s defensive reactions, but also to allergic reactions and asthma. This may explain the previous observations of increased asthmatic symptoms in a state of sleep deprivation.”
The study was published in the PLOS ONE journal on October 23.