Jet Lag Peptide Vital To Travel Recovery

When people take long airplane flights, their bodies generally take a day to readjust for every time zone crossed. It turns out that mice, too, follow this rule of thumb for jet lag recovery. Both rodents and humans are slaves to their internal 24-hour molecular clocks, or circadian rhythms, which regulate sleep and activity patterns. Researchers in Japan, however, have freed mice from the negative effects of time-zone shifts. The group, led by Hitoshi Okamura of Kyoto University, made rodents jet-lag-proof by genetically engineering their brains to lack a pair of receptor proteins, V1a and V1b, that typically bind the neuropeptide vasopressin. When the scientists shifted the animals’ usual light-dark cycle ahead by eight hours, the mice adjusted both their activity and body temperature cycles in less than half the time that their nonengineered counterparts did (Science 2013, DOI: 10.1126/sci​ence.1238599). The researchers suggest the finding might one day lead to treatments for frequent travelers and sleep-disrupted shift workers, who are at elevated risk for cancer and other diseases. Vasopressin, though, regulates blood vessel constriction and water retention in the body, so targeting it directly may prove difficult.