Stress actually damages DNA and depletes the melanocyte stem cells within hair follicles that are responsible for making the pigment-producing cells. The depletion leads to irreversible hair graying, the lead author of the study, Emi Nishimura, of Kanazawa University in Japan, said in a news release. The study is published today in the journal Cell.
Using mice, the researchers also showed that a "caretaker" gene called ATM serves as a checkpoint to protect against melanocyte stem cell changes. That's why people with an aging syndrome called Ataxia-telangiectasia, which is caused by a mutation in the ATM gene, go gray prematurely.
Gray hair is one of the most obvious signs of aging. But changes to other body stem cells have been reported, and it appears stresses on the stem cell pool and maintenance failures in the function of cells are strongly linked to accelerated aging. But it's not clear if anything can be done to stop these process -- at least not yet. Hang on to your L'Oreal and Just for Men.
-- Shari Roan
Photo credit: Advanced Cell Technology.