Novel way to control internal body clock

The discovery of a small molecule that controls internal body clock can help manage circadian rhythm and treat problems like sleep and anxiety disorders, say researchers.

These problems are usually found in people who do late night shifts or frequently travel by air.

Circadian rhythm refers to biological processes that cycle every 24 hours.

In mammals, the internal clock that maintains circadian rhythm is essential for normal physiological functions.

The rhythms can, however, be disrupted, and dysregulation of circadian rhythm is associated with many disorders, including metabolic disease, anxiety, depression, schizophrenia and sleep disorders.

Thomas Burris, chair of pharmacological and physiological science at Missouri-based Saint Louis University, examined compounds that target a protein called REV-ERB, which appears to play a key role in regulating mammals' internal clocks.

"It has been suggested that REV-ERB is a core component of our clock. Mice without it are arrhythmic. This study demonstrated that when we give mice a synthetic compound that turns REV-ERB on, it altered their circadian rhythm," Burris noted.

The team examined effects of the REV-ERB drug on patterns of sleep and wakefulness and found that the compound increases wakefulness, reduces REM rapid eye movement sleep and slow-wave sleep and decreases anxiety.

Frequently, drugs that increase wakefulness also increase anxiety and drugs that decrease anxiety also decrease arousal.

"The REV-ERB drug, on the other hand, appears to target the clock in a way that is distinct from these common pathways. Further, the REV-ERB drug appears to be associated with a suppression of reward-seeking behaviour," the authors said.

The paper appeared in the journal Nature Communications.