stress is Often accused of graying of hair. This phenomenon is also called the syndrome of Marie-Antoinette (Marie Antoinette syndrome), which, according to some sources, suddenly turned gray after getting captured during the revolution. However, not everyone is convinced of the veracity of this story, like the fact that the hair can quickly turn gray after a sudden and severe stress. There are a lot of cases, when nervous tension that lasts for months or weeks, can cause this effect.
“everyone has a story about how stress affected their body, especially on skin and hair. We wanted to find out whether this is true communication, and if so, how stress leads to changes in various tissues,” says senior author I-Chieh Hsu (Ya-Chieh Hsu) from Harvard University.
Explain what the specialists couldn’t understand how my hair turns gray during times of stress and wondered if he could really lead to such consequences. It was believed that the emotional tension only accelerates the aging process, and it already makes the hair gray.
a Group of scientists from Harvard University suggested that cortisol – the stress hormone – can play a role in this process.
“the Stress always increases the level of the hormone cortisol in the body, so we thought that cortisol may play a role,” notes Hsu.
To find out if it really is, scientists have removed mice adrenal glands – paired endocrine glands, which secrete this hormone.
“But their hair will still turn gray from stress,” said Hsu, adding that the results surprised researchers.
After a time, scientists noticed that the fur of mice that experience stress begins to gray due to the exhaustion of specific stem cells that are at the base of the hair follicle. This observation was the first success scientists on the way to unraveling the mechanism of color changes of the hair.
These stem cells turn into cells that produce pigmentt the growth of hair. But in times of great stress they hiperactividad. All this leads to a depletion of “reservoir” cells that produce pigment. For this reason, the hair in the future acquire a grayish hue.
“When we began to study this process, I assumed that stress is harmful to the body. But its impact is even more destructive than I imagined, says Hsu. – Just a few days, all regenerating the pigment stem cells were lost. As soon as they disappear, the production of the pigment becomes impossible. The damage is irreversible.”
However, this discovery did not explain how stress activates the stem cells. This question helped to answer the subsequent research.
Experts have discovered that a neurotransmitter called norepinephrine, apparently, causes their excessive depletion.
to check this out, the researchers removed the mice have main source of noradrenaline – the adrenal gland. To the surprise of scientists, this has not stopped stress-induced graying of hair.
to Unravel the mystery helped another source of norepinephrine – sympathetic nervous system, which is responsible for the reaction of fight or flight.
it turned Out that severe stress leads to the release of norepinephrine from neurons of the sympathetic nervous system. Neurotransmitter subsequently activates mass migration of stem cells from the base of the hair follicle, and it is this process that directly links stress with the appearance of gray hair.
“a lot of stress, especially the reaction of “fight or flight”, it is traditionally believed useful for the survival of the animal. But in this case it causes persistent depletion of stem cells,” says lead author Bin Zhang (Bing Zhang).
As often happens, the discovery has raised many questions. So, today it is unclear whether this mechanism is part of the natural process of appearance of gray hair as you age. In addition, specialists do not know whether stress-induced hair color change to beKorennoy version of what naturally happens to many people for several decades? All this to be answered in future works.
In General, according to the authors, their study helps to understand how much stress can play a direct role in stem cells. Maybe it will help in creating new methods of preventing graying of the hair. And, equally important, the results will help scientists to study the effects of stress on other organs.
the results of the study is discussed in more detail in an article published in Nature.
we will Add that earlier scientists have found genes that protect the body from aging. In addition, the authors of the project “Conduct.Science” (nauka.vesti.ru) wrote that early graying and baldness can signal serious heart disease.