Deutschlandfunk (Germany): why lack of sleep can be fatal

120 years ago, Russian researchers day and night forced the puppies to move. Five days later they died. In fact, they were able to live longer without food than without sleep. Maybe they were dead because they had to keep moving? In isolation to study the effects of lack of sleep is not easy. Dragan Rogulev (Dragana Rogulia) works with fruit flies at the Harvard medical school. “It’s hard to get animals to stay awake. The urge to sleep is incredible. Even when you shake the vial, the flies somehow manage to cling to blends of cotton and get some sleep”.

“All animals without sleep, and after 20 days died”

Therefore, the neurobiologist explores genetically modified flies. At room temperature these mutants sleep properly, so they grow. But when the temperature in the laboratory rises to 29 degrees in their brain switch genetic toggle switch, which suppresses the craving for sleep. Flies are active during the day and night, but so significantly reduces their life expectancy. Normal fruit flies at this temperature, live 40 days, and all flies without sleep died after 20 days.

But what did they die of? Dragan Rogulev together with his team carefully researched all of their bodies. “The sleep-deprived flies is a dramatic increase in aggressive oxygen compounds, but only in the intestine. We were shocked, it is really very unusual.”.

Dragan Rogulev expected that lack of sleep causes problems throughout the body, but actually the problem is concentrated in the gut. In this the researchers were able to verify this by typing fluorescent substance into the cells. In the intestine it glowed brighter, because there is concentrated oxygen radicals. The luminescence intensity gradually decreased when the flies at lower temperatures, again was able to sleep.

A group of researchers conducted experiments on mice, which is constantly pushed by a slowly rotating cylinder, not allowing them to stop moving. Two days later and they are in the intestine and in the intestine — increased level of oxygen radicals, and after five days cells began to die.

For reasons of protection of animals experiments on mice to continue did not. Therefore, the group of scientists headed DRAC, Dragana Rogulev returned to the flies and begin to introduce them to antioxidants as a therapy. Substances such as linoleic acid, resveratrol or NAC, eliminate oxygen radicals.

Antioxidants protect flies from lack of sleep

“It was amazing. Antioxidants eliminate aggressive oxygen radicals, and it saved flies, despite the lack of sleep! In wildest dreams I never could have imagined. Every morning gathered the entire group and excitedly counted the number of flies still alive. Other flies that did not sleep, looked more and more painful, almost did not move. But these seemed full of energy. Sure, maybe they were stupid or become retarded, we don’t know. We want to test,” says the researcher.

Not only biologically active substances, can compensate for the genetically modified flies lack of sleep. This can be done using genetic techniques that Dragan Rogulev activates enzymes in the gut of flies. They “neutralize” oxygen radicals. In the brain, on the other hand, the same enzymes do not show the effect. There is a link between sleep and the gut is really very specific.

“The work is definitely very interesting”

The results obtained are very interesting, said Gilestro Giorgio (Giorgio Gilestro) from Imperial College London. He found that fruit flies have very different individual needs in sleep.

The solution is not in the brain but in the gut

“It was always a mystery why dead animals that are completely deprived of sleep. And now it turns out that the answer is not in the brain but in the gut. It’s incredible,” says Galestro.

But the researcher warns against the transfer of these results to humans and try to compensate for the lack of sleep antioxidants. Dragan Rogulev agree with him. For her, first and foremost, it is important not medical use — her experiments she wants to understand why sleep so early arose in the evolution of animals.