Discovery of hair-growth signals may lead to cure for baldness

Scientists have discovered the key steps that trigger hair growth in research that might soon lead to cures for baldness and unwanted body hair.

The study found the chemical signals that turn an unspecialised stem cell in the skin into a specialised hair follicle, said Professor Elaine Fuchs, who led the team from Rockefeller University in New York.

"These studies raise the possibility that drugs to activate these natural factors could promote hair-follicle growth in wanted places, and inhibitory drugs could prevent hair growth in unwanted places," Professor Fuchs said.

Previous work by the professor showed how it was possible to increase the number of hair follicles on the skin of laboratory mice by boosting the production of a chemical signal called beta-catenin.

Unfortunately, this proliferation of hair follicles also raised the risk of skin cancer. The latest research, published in the journal Nature, could address the problem because it has identified two other chemical signals that carefully regulate the production of beta-catenin.

"Unlike the earlier experiments, in which we genetically altered the animals in these experiments, we have altered the stem cells using external factors that the skin normally makes," Professor Fuchs said. "In doing so, we have been able to elicit the initial responses that occur in the development of the hair follicles."

Two natural signals – proteins called wnt and noggin – change the stem cell's shape so that it can separate from adjoining cells and move down into the deeper layers of the skin where it can form a small indentation that becomes a hair follicle.

"Skin turns over every two weeks, so there is an enormous reservoir of stem cells there ... we are trying to answer the question of whether we can coax some skin stem cells to become hair," she said.