Recently, two studies conducted by scientists at Harvard Medical school and the University of Tsukuba, Japan, have identified specific neurons in the brains of lab mice that can stimulate hibernation or a state of dormancy in them. These findings can help scientists know how to put other animals and humans in a similar decreased physiological state. Putting humans in this state of lowered energy use and reduced metabolism can be quite useful in serious illnesses, or injuries; this will help save their lives until treatment is given. Being able to hibernate humans during travels to space is another process scientists are considering as a result of these findings.
Animals in this state are usually inactive physically and psychologically; this is because they have reduced physiological activities in their bodies. They experience hypothermia- a condition of reduced body temperature. As such, their body’s metabolic activities decrease, and they can conserve energy during long periods of low temperature where there is less abundant food. It is known that specific parts of the brain are involved in controlling the body’s temperature, but this research has further helped to identify nerve cells that function as thermoregulators.
These two studies on hibernation were in the publication, Nature. In one of the studies, scientists from Japan discovered specific nerve cells in the brains of the lab mice. These neurons can be stimulated artificially to put the mice in a state of decreased activity. The nerve cells- Q neurons, expressed a neurotransmitter referred to as QRFP. It was noticed that when the nerve cells in the hypothalamic part of the brain were stimulated by either a chemical or light, the mice had a drop in their body’s temperature, lower heart rate, no deep breathing, and reduced rate of metabolism. Stimulating the neurons triggered a hibernation-like process in the lab animals, which was longer than the usual torpor cycles they experienced when starved for 24 hours. Hereafter, the lab animals recovered and showed no signs of harm.
In another study, scientists from Harvard Medical School discovered nerve cells that cause torpor in the lab mice. These were stimulated as the lab animals entered into the torpor process. By inhibiting the cells, they noticed that they could hinder the torpor process from happening.
Although the findings are not yet applied to humans, it is said that if they could identify similar neurons in humans, it could be a useful means of therapy.