Sufficient rest during holidays restores functions associated with DNA regulation

Going on vacation can impact shift workers on the level of gene function. According to a recent study, sufficient rest during vacation time restored functions linked to DNA regulation in shift workers deprived of sleep.

Sufficient rest and recovery are especially important for people with a background of long-term sleep deprivation. Image Credit: MOSTPHOTOS.

Sleep deprivation for a long time is detrimental to health, raising the risk of somatic and psychiatric conditions, like cardiovascular diseases and depression. Despite this fact, not much is known about the molecular biological mechanisms triggered by sleep deprivation that underpins the associated adverse health effects.

In a newly published research work, the University of Helsinki, the Finnish Institute for Health and Welfare, the Finnish Institute of Occupational Health, and the Finnair airline studied the complex changes in DNA methylation in the case of shift workers. DNA methylation represents an epigenetic regulation that alters the function of the genes and controls the activity of the genes without modifying the sequence of bases in the DNA.

DNA methylation causes short-term genetic modifications that are not well understood. Although methylation is associated with the surroundings, more studies are required to find out the effect of the environment on gene function and epigenetic regulation.

The newly published study provides scientists with new data on DNA methylation as well as the biological mechanisms that affect sleep disorders associated with shift work (shift work disorder, or SWD). The latest study was published in the leading Scientific Reports journal series.

Changes to DNA methylation can mediate infections caused by sleep deprivation

In total, 32 shift workers took part in the study, and among these, 21 had shift work disorders and the remaining was in the control group. The researchers investigated the dynamic modifications to DNA methylation through a genome-wide study during work and post a holiday period.

DNA methylation changes that influenced gene function were detected in study subjects suffering from sleep disorder induced by shift work. The results showed that rest and recovery at the time of the holiday periods also restored DNA methylation in cases where variations had been noticed during the work period.

The research work demonstrated the dynamic nature of DNA methylation, which was specifically highlighted in the activity of NMDA glutamate receptors. The most robust proof was obtained from the GRIN2C receptor: during the work period, the methylation level of a particular CpG base pair in the regulatory region was lower in subjects afflicted by shift work disorder.

Based on the results, we can deduce that changes to the DNA methylation of white blood cells are associated with shift work disorder. These changes, such as low methylation levels observed during the work period, are probably linked to sleep deprivation and related inflammatory consequences which DNA changes may mediate.”

Alexandra Lahtinen, MSc, Doctoral Student, University of Helsinki

“Sufficient rest and recovery are important for everyone, but especially important for people with a background of long-term sleep deprivation due to, for example, living habits or irregular working conditions. Having said that, it's positive that the subjects recovered from at least some of the changes related to shift work disorder observed in the study,” concluded Professor Tiina Paunio from the University of Helsinki and the Finnish Institute for Health and Welfare, who was the principal investigator of the research work.