Study: Changing sleep cycles has benefits

New research suggests that subtle disruptions to circadian rhythms — as happens with a long flight across time zones — might actually be beneficial for brain health.

The study by researchers at Northwestern University found that fruit flies carrying a gene for Huntington’s disease appeared to receive a protective boost against the brain-damaging illness when researchers changed the insects’ sleep cycles in a way similar to jet lag. The team also found that silencing a circadian clock-controlled gene produced a similar benefit.

“It seems counterintuitive, but we showed that a little bit of stress is good,” Ravi Allada, a physician who heads the neurobiology department at the university’s Weinberg College of Arts and Sciences and Pathology, said in a statement. “We subtly manipulated the circadian clock, and that stress appears to be neuroprotective.”

The team says the findings could lead to new strategies for preventing or slowing the onset of progressive brain diseases such as Huntington’s disease, a fatal disorder that kills nerve cells and damages the brain. As with other progressive brain diseases, people who have Huntington’s often undergo profound changes to their sleep cycles, such as sleeping more than usual or having difficulty sleeping.

The study — which appeared Tuesday in the journal Cell Reports — focused on fruit flies, whose brains are wired for sleeping and waking cycles in ways that are similar to human brains.

To test the effect of disrupted sleep cycles, the team altered the usual 24-hour day rhythm for a group of insects. The fruit flies instead were put on 20-hour cycle whose periods of light and dark were altered every day — creating conditions not unlike having to hop a four-hour red-eye flight from Los Angeles to New York every day.

What the researchers found is that the relatively minor stress of daily jet lag seemed to strengthen the brain in important ways and slow the progression of Huntington’s disease: Fewer proteins linked to the disease were found, the team said, and fewer brain cells died.