Stimulation: ultrasonic hibernation

In the cold season or when there is a short supply, some mammals and birds fall into a kind of short- or long-term rigidity. This is called coma or hibernate. Body temperature drops dramatically, metabolism changes and becomes slower. This state is very energy efficient and can last from a few hours to a few months – the same as with a real hibernation. It is believed that the state of certain neurons is controlled in the hypothalamus, a brain region.

The idea of ​​artificially creating a similar condition in humans has been around for many decades, for example for patients in life-threatening situations or for months-long space flights, such as Mars. American research team Yaoheng Yang The University of Washington is now taking a basic step, but initially only in mice and rats. Like researchers now In the journal “Nature Metabolism” They reported, they were able to use a non-invasive method to treat the responsible neurons from the outside.

artificial hibernation

First, the brain region responsible for hibernation in mice was activated with short ten-second ultrasound pulses. The source was installed on the heads, so that the animals could move freely. In fact, the stimulation of neurons may have set off a chain of bodily processes: the body temperature instantly dropped by three to three and a half degrees Celsius. Heartbeats slowed and the bodies of both male and female mice used less oxygen. Metabolism shifts from sugar to fat burning. Within two hours, all bodily functions returned to normal.

The team then built an automated system that controls the ultrasound transmitter. Whenever the animals’ body temperature rose again, a new pulse was sent. According to the researchers, it was possible to maintain hibernation for 24 hours. There was no evidence of physical harm or discomfort.

Also for humans?

The method has also been tested on mice. As expected, their body temperature didn’t drop much, only by 1 to 2 degrees Celsius. Animals do not hibernate naturally. This suggests that stimulation by ultrasonic pulses in general also triggers something in warm-blooded animals. So the method can also be suitable for the human body, which actually does not have a similar resting position.

As the study authors concluded, this method actually has the potential to achieve the long-sought goal of putting people into a kind of artificial hibernation, for example for very long space flights. Unlike previous methods, such as those that use medication, ultrasound is relatively safe. However, until then, there is a lot of research to be done.