By studying the brains of fruit fly , scientists found that their neurons can adapt to keep insects awake in dangerous situations, even though they are tired, or fall asleep quickly after a hard day. The results of this study will help create new ways to treat insomnia in humans and improve sleep quality.
When we get sick or lack sleep, we feel more sleepy. However, in dangerous or disturbing situations, no one can fall asleep regardless of the level of fatigue. That is, neurons that regulate sleep can distinguish between appropriate and inappropriate sleep in some way.
To reveal the mechanisms that regulate this, scientists from Washington University in St. Louis and the University of Missouri, Kansas City, USA studied sleep in fruit flies. Their sleep and wake-up habits are similar to ours: they are active during the day, sleep at night, and like to take a nap during the day, especially in hot weather. Caffeine makes fruit flies more active, while human sleeping pills make them drowsy. Therefore, the results of this study, published in the journal Public Library of Science, Biology, will help develop new ways to treat insomnia and improve the quality of sleep in humans.
However, there is a significant difference between us and insects: the brain of fruit flies is a million times smaller than that of humans. This allows you to determine the role of each nerve cell in it. The author focuses on 24 brain neurons that control sleep and awakeness in Drosophila.
These neurons receive and respond to signals sent by other neurons in the form of neurotransmitters. Scientists investigated whether external stimuli affects the sleep of fruit flies and how their 24 neurons respond to dopamine and allatostatin A and sleep-promoting glutamate. As we all know, Allatostatin A plays a role in dietary behavior, and now it seems to be important in sleep regulation as well.
Sleep can enhance memory and improve learning ability. After a busy day, both humans and flies slept more. Scientists have shown that living in an environment full of relatives and new signals, or learning new behaviors, can lead to molecular changes in sleeping neurons in the fruit fly. They become less sensitive to dopamine, so they want to sleep more.
On the other hand, when researchers disrupt flies by regularly shaking vials containing flies, neurons produce allatostatin A and glutamate. Although exhausting, the combination of two opposite signals keeps the flies awake under stress.
The causes of insomnia in humans are not completely clear. Some evidence suggests how sleep centers in the brain explain the genetic tendency of neural signals. If there is any interference in this system, the brain will receive conflicting signals and a tired person will not be able to fall asleep. By understanding how opposite signals appear simultaneously, scientists can develop new ways to treat insomnia.
