Have you ever wondered why you have hair on your legs, but not on the soles of your feet?
Or why we have a lot of hair on the head, but there is not a single hair on the palms?
This question has remained unresolved for many years for doctors, researchers and other scientists of the complex technique of the human body.
For decades, science has been limited to considering that it was evolutionary feature some animals, but the physiological explanation of how it is produced has been a question until recently.
Scientists from the University of Pennsylvania School of Medicine have investigated this “secret” for many years and now claim to come up with an answer.
Study published in the journal journal Cellular Reports, indicates that the "culprit" not We get hair in certain areas of our body – this is a special type of molecule, for more signals – a protein.
According to researchers, it’s about Dickkopf 2 (DKK2), which blocks the so-called “WNT signaling paths,” the cellular channels that, among other things, are responsible for triggering hair growth.
“In this study, we show that skin in bare areas naturally produces an inhibitor that prevents WNT from doing its job,” he told the magazine. Newsweek Sarah E. Millar, one of the authors of the study.
“We know that the WNT signaling is necessary for the development of hair follicles, blocking it, causing bare skin and activating it, which leads to the formation of more hair,” he said.
But why do some animals have hair on most of their bodies while others do not?
The study suggests that it has been known for many years, an evolutionary adaptation.
The study finds that some animals have evolved to produce DKK2 in certain parts of their bodies in order to help them better survive in their environment,
For example, a hairless arm will serve more for storing tools or other tasks, while the absence of lint on the soles of the legs will help to walk better.
However, in cold climates, it would be better if they were covered, as in the case of polar bears.
In order to reach these conclusions, the team analyzed the skin of the legs of the mouse (which, like people, does not have hairs on its plants) and compared it with other animals that do, for example, with rabbits.
Comparing the levels of DKK2 between the two species, they found that the amount of protein is noticeably less on the skin of animals that have hair on the sole of their feet.
Meanwhile, the level of the molecule was much higher in areas where hair does not grow than in the most bizarre areas.
Research shows that in these areas there are no WNT signaling pathways, hair generators, but protein blocks them.
Now researchers are hoping that the detection can be used for new hair growth studies, for treating certain diseases, or for future treatments for people who have suffered severe burns or accidents.