London - A bizarre experiment in which scientists keep the brains of fruit flies alive in a dish for six days may hold the key to explaining – and eventually treating – jet lag.
After removing the brains of the flies, researchers at the University of California used a low-light camera to document how the circadian clock circuit is “reset” by light.
The study – published in Current Biology this year and funded by the US government– marks the first time that scientists have seen in real time how specific neurons in intact brain systems react to light cues, which are comparable to rapid travel across different time zones.
A single light pulse cues the biological clock of the fruit fly brain to shift two hours ahead of its original schedule and then effectively resets itself, researchers have discovered.
“Broad features of this pattern of circadian circuit response to light may be applied to humans and other mammals,” they say.
Lead researcher Todd C Holmes, professor of physiology and biophysics at the University of California, Irvine School of Medicine, said: “Remarkably, our work indicates that the way you feel while jet-lagged exactly reflects what your nervous system is experiencing: a profound loss of synchrony.”
The idea of speeding up the disruption of the body clock before travel in such a way that it resets itself more quickly – in an estimated two days – could “lead to treatments that would have a big impact on our travel practices”, Holmes said.
For the time-shift tested, recovering from jet lag would normally take four days.
A longer shift, for example that experienced in flying from London to Los Angeles, would probably require a longer time for recovery.
“That two-day difference is quite a bit if it means you feel great from the beginning of your arrival, say, in Italy,” Holmes noted. “You’re going to feel bad on the plane in any event – it is best to get the adjustment over with so you can enjoy your destination.”
Commenting on the study, Professor Erik Herzog, an expert on circadian biology, said: “With extraordinary cellular resolution, the researchers show that some cells shift faster than others following a pulse of light. This may become a useful therapy in treating jet lag.”
The Independent