Night shifts, jet leg disrupt rhythm of genes
For those who work in night shifts or miss on sleep owing to heavy air travel, it is time to set the clock right to get rhythm of your genes back in shape.
A University of Surrey study has found that the daily rhythms of our genes are disrupted when sleep times shift.
"This research may help us understand the negative health outcomes associated with shift work, jet lag and other conditions in which the rhythms of our genes are disrupted," said professor Derk-Jan Dijk from the sleep research centre at University of Surrey, England.
Researchers placed 22 participants on a 28-hour day in a controlled environment without a natural light-dark cycle.
As a result, their sleep-wake cycle was delayed by four hours each day.
The team then collected blood samples to measure the participants' rhythms of gene expression.
During this disruption of sleep timing, there was a six-fold reduction in the number of genes that displayed a circadian rhythm (internal body clock with 24-hour cycle), said the study published in the journal Proceedings of the National Academy of Sciences.
"Over 97 percent of rhythmic genes became out of sync with mistimed sleep and this really explains why we feel so bad during jet lag, or if we have to work irregular shifts," said co-author Simon Archer from the school of biosciences and medicine.
The study also revealed which genes may be regulated by sleep-wake cycles and which are regulated by central body clocks.
This finding provides new clues about sleep's function as separate from the circadian clock.
"The results also imply that sleep-wake schedules can be used to influence rhythmicity in many biological processes, which may be very relevant for conditions in which our body clocks are altered, such as in aging," added professor Derk-Jan Dijk.
(Posted on 21-01-2014)