A Poor Night’s Sleep May Be In Your Genes

A gene that regulates sleep and circadian rhythm may also be linked to aging, according to a new study, which may explain the increased risk for diseases that accompany poor sleep habits.

A lack of sleep can contribute to a host of negative health effects, and researchers say they now understand why. Working in mice, researchers found that a gene called SIRT1, which regulates circadian rhythm and sleep, is also linked to aging, according to a study published today in the journal Cell. The findings may explain why the risk for diseases such as cancer and diabetes increases when your circadian rhythm is disrupted.

Circadian rhythm is regulated in the brain by a 24-hour cycle of light and darkness. Disruption is common among shift workers, and has been linked to a number of diseases, such as diabetes, cancer and obesity.

“Just about everything that takes place physiologically is really staged along the circadian cycle,” study author Leonard Guarente, MD, a professor of biology at the Massachusetts Institute of Technology, said in a statement. “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.”

Sean Hagberg, PhD, assistant clinical professor of neuroscience at the University of New Mexico and head of scientific community relationsat the CellHealth Institute, said your circadian rhythm keeps your body in line, and helps ensure that your body processes occur when they are supposed to.

“The circadian rhythm organizes all of the timing of all the activity in your body like your personal calendar,” he said. “Imagine what it would be like if you didn’t keep a calendar? Nothing would happen on time and even less would get done.”

Researchers engineered mice with different levels of SIRT1, and found that those with lower levels of the gene had a more difficult time adjusting their circadian clock as the day went on. SIRT1 levels decrease as you age, researchers said, so disruptions to your internal clock pose more damage. Adjusting the levels could fix the disruptions and help ward off diseases related to circadian rhythm.

“If we could keep SIRT1 as active as possible as we get older,” Dr. Guarente said in the statement, “then we’d be able to retard aging in the central clock in the brain, and health benefits would radiate from that.”

But a therapy to increase SIRT1 wouldn’t help unless people took steps to help their circadian rhythm on their own, Dr. Hagberg said.

“The basic problem for humans is that we have organized our lives to prevent ourselves from having good circadian rhythms,” he said. “The key component is sunlight during the day and darkness at night, but most of us spend the day indoors and with artificial light at night.”

So instead of waiting around for a gene therapy to help fix your circadian rhythm, Hagberg said to just take a walk outside.

“The simplest thing you can do to improve your circadian rhythms and improve cell function is to get out in the daylight,” he said.

By Amir Khan