Scientists have discovered a new mechanism that governs how body clocks react to changes in the environment, a finding that could help treat detrimental effects of chronic shift work and jet lag.
The University of Manchester team's findings show that the enzyme casein kinase 1epsilon (CK1epsilon) controls how easily the body's clockwork can be adjusted or reset by environmental cues such as light and temperature.
Internal biological timers (circadian clocks) are found in almost every species on the planet.
In mammals including humans, circadian clocks are found in most cells and tissues of the body, and orchestrate daily rhythms in our physiology, including our sleep/wake patterns and metabolism.
"At the heart of these clocks are a complex set of molecules whose interaction provides robust and precise 24 hour timing. Importantly, our clocks are kept in synchrony with the environment by being responsive to light and dark information," said Dr David Bechtold, who led the study.
The research identifies a new mechanism through which our clocks respond to these light inputs.
During the study, mice lacking CK1epsilon, a component of the clock, were able to shift to a new light-dark environment (much like the experience in shift work or long-haul air travel) much faster than normal.
Researchers showed that drugs that inhibit CK1epsilon were able to speed up shift responses of normal mice, and critically, that faster adaption to the new environment minimised metabolic disturbances caused by the time shift.
"We already know that modern society poses many challenges to our health and wellbeing - things that are viewed as commonplace, such as shift-work, sleep deprivation, and jet lag disrupt our body's clocks. It is now becoming clear that clock disruption is increasing the incidence and severity of diseases including obesity and diabetes," Bechtold said.
The study is being published in the journal Current Biology.
A graphic provided by Australian Maritime Safety Authority shows an area in the southern Indian Ocean that the AMSA is concentrating its search for the missing Malaysia Airlines Flight MH370. (AP).