Several brain-based immune proteins may regulate sleep: Study

New York: A new study reveals that sleep may be regulated in part by several brain-based immune proteins which could pave the way for new therapies to treat chronic sleep disorders and sleep disturbances secondary to other diseases.

As per the study, the immune proteins, collectively called inflammasome NLRP3, recruit a sleep-inducing molecule to trigger somnolence following sleep deprivation and exposure to a bacterial toxin.

Animals lacking genes for this protective immune complex showed profound sleep aberrations.

Study senior investigator Mark Zielinski from Harvard Medical School, "Our research points, for the first time, to the inflammasome acting as a universal sensing mechanism that regulates sleep through the release of immune molecules".

 

In a series of experiments, the scientists demonstrated that following sleep deprivation or exposure to bacteria, the inflammasome activates an inflammatory molecule called interleukin-1 beta, known to induce sleep and promote sleep intensity.

The brain cells of mice lacking the gene coding for inflammasome NLRP3 showed a marked absence of this sleep-inducing molecule.

Going a step further, the investigators compared the behaviour, sleep patterns and electrical activity in the brains of mice lacking the inflammasome gene to those in a group of mice with intact inflammasome genes.

Mice lacking the inflammasome gene had abnormal sleep responses following sleep deprivation.

On average, such mice slept less and experienced more sleep interruptions than mice with their genes intact.

The latter group also slept more and harder following bacterial exposure -- the expected physiological response following infection, the researchers said.

The study was published in the journal Brain, Behavior, and Immunity.