Jet lag eased in mice by blocking gene

A 'molecular basis' of jet lag has been identified and blocked in mice by inhibiting the activity of a single gene, according to scientists.

The team, from Oxford University, looked at the genes that govern the way our body adjusts to changing patterns of light and darkness. They found 100 genes that help to reset the body clock, and also one protein, SIK1, that slows down this response, acting as a 'molecular brake'.

When the gene that expresses the SIK1 protein was blocked in mice, the researchers found that the mice were able to adjust to shifting light patterns much faster.

'We've identified a system that actively prevents the body clock from re-adjusting', said Dr Stuart Peirson, who led the team. 'If you think about it, it makes sense to have a buffering mechanism in place to provide some stability to the clock. The clock needs to be sure that it is getting a reliable signal, and if the signal occurs at the same time over several days it probably has biological relevance. But it is this same buffering mechanism that slows down our ability to adjust to a new time zone and causes jet lag'.

The researchers investigated a part of the brain known as the suprachiasmatic nuclei that governs the body's 24-hour cycle. This uses information from the eyes about environmental light that is used to synchronise the body clock.

It is hoped that by targeting the SIK1 molecule, scientists will be able to create a drug that can alleviate the symptoms of jet lag.

'We're still several years away from a cure for jet-lag, but understanding the mechanisms that generate and regulate our circadian clock gives us targets to develop drugs to help bring our bodies in tune with the solar cycle', said Professor Russell Foster, from the Oxford University Sleep and Circadian Neuroscience Institute.

Mental health disorders such as schizophrenia have recently been linked with an out-of-sync body clock. Professor Foster added: 'Such drugs could potentially have broader therapeutic value for people with mental health issues'.