Experiments carried out with mice show that stress is capable of producing gray hair even before natural aging.
According to the study, in very stressful situations, neurons that are in the vicinity of the wires release a substance that ends up depleting the cell factories of the natural "ink" of the hair. Thus, when new strands are born, they no longer have the same color as before.
Researchers from the USA and Brazil completed the work, which has just been published in the scientific journal Nature. "Although only one of the experiments was done with human cells, it is very likely that the mechanism we saw in the mice will be shared with us. Physiology is very similar", says Thiago Mattar Cunha, professor at FMRP-USP (USP Medical School in RibeirÃ£o Preto) and one of the Brazilian authors of the research.
There is no lack of reports, including historical ones, about the effects of high levels of stress on the hair. History says, for example, that Marie Antoinette (1755-1793), France's last queen before the French Revolution, had all the white threads the night before her execution in the guillotine.
Cunha says he witnessed the same whitening in the coat of mice he studied during research on the biochemical mechanisms of pain, an area that is his specialty at USP. When they injected rodents with a substance capable of causing intense pain, he and his colleagues observed, four weeks later, that the animals' hair had become white. "We were intrigued and started trying to understand that," he said.
Translated by Kiratiana Freelon