Male baldness linked to stem cells

Philadelphia - An inability of scalp stem cells to develop into the type of cells that make hair follicles may be an underlying cause of male-pattern baldness, msnbc.com reports.

Lead author George Cotsarelis, M.D., professor of dermatology at the University of Pennsylvania, says the results offer new hope that bald people could regrow their hair with a future treatment.

Contrary to the long-held belief that bald people have a depletion of hair-follicle stem cells necessary for hair growth, the new study suggests that bald people have the same number of stem cells as anyone else. Thus, if scientists could coax the stem cells into producing more follicle progenitor cells, it would be possible to generate bigger hair follicles that could grow hair.

Dr. Cotsarelis and colleagues took skin cells from the bald and nonbald parts of the scalps of people with androgenetic alopecia and tagged each cell with a marker. By using different markers to distinguish between stem cells and follicle progenitor cells, they were able to count the number of each type.

Though researchers found the same number of stem cells in bald scalps as in nonbald scalps, they found fewer follicle progenitor cells in bald scalps.

Investigators conclude that baldness was occurring because the stem cells were unable to complete their normal development and become follicle progenitor cells.

“If we figure out … the factors that are necessary to activate the stem cells to make progenitor cells, there should be a way to reverse those small follicles to make them large,” msnbc.com quotes Dr. Cotsarelis as saying.