Studies over the past decade have shown the wide-ranging effects of the body’s “clock” or circadian rhythm on our mental and physical health. Many have linked a disrupted body clock to increased risk for everything from depression to cancer to diabetes to even an early death. People who work at night seem to be particularly at high risk for some of these problems.
Researchers have been able to map out the genes involved in the circadian clock with fairly good precision. A new study goes even further: illustrating how one particular gene — one important in the aging process — also helps “set” the clock.
The SERT1 gene is known to be important in preventing age-related health problems, through its control of the stress response and various hormone cascades. By manipulating its levels in the mouse brain, the team at MIT has now shown that it also plays an important role in the biological clock.
What's now emerging is the idea that maintaining the circadian cycle is quite important in health maintenance, and if it gets broken, there's a penalty to be paid in health and perhaps in aging.
The mice with no SERT1 expression had longer circadian cycles than normal mice, and those with a lot of SERT1 expression had shorter cycles. But the mice with high SERT1 levels also had an added benefit: They didn’t experience the normal decline in circadian rhythm as they got older. It was also true, as in earlier studies, that younger mice (with normal SERT1 levels) had a much easier time adjusting to interrupted light-dark cycles than older mice.
There’s some thought that boosting SERT1 expression in the brain or increasing the number of its receptors could help slow the aging process and perhaps reduce the risk of the diseases that come along with it.
“If we could keep SIRT1 as active as possible as we get older, then we'd be able to retard aging in the central clock in the brain, and health benefits would radiate from that,” author Leonard Guarente said in a statement.
Guarente’s lab is also working on the question of whether our diets can play a role in circadian rhythm. They suspect that high-fat diets may work to disrupt the “clock.”
“Just about everything that takes place physiologically,” adds Guarante, “is really staged along the circadian cycle. What's now emerging is the idea that maintaining the circadian cycle is quite important in health maintenance, and if it gets broken, there's a penalty to be paid in health and perhaps in aging.”
So while the research is still underway, the preliminary advice is clear: As much as you can, sleep on a regular cycle – and don’t deprive yourself of the stuff, which may hold more clues to our health than we realize.
The study is published in the journal, Cell.