Scientists regrow hair on wounded skin

pathways in damaged skin of laboratory mice. Experiments focused on cells called fibroblasts that secrete collagen, the structural protein most responsible for maintaining the shape and strength of skin and hair. Researchers activated the sonic hedgehog signalling pathway used by cells to communicate with each other. The pathway is known to be very active during the early stages of human growth in the womb, when hair follicles are formed, but is otherwise ◗ stalled in wounded skin in healthy adults. Researchers said this possibly explains why hair follicles fail to grow in skin replaced after injury or surgery.

“Our results show that stimulating fibroblasts through the sonic hedgehog pathway can trigger hair growth,” said Mayumi Ito, an associate professor at NYU. Regrowing hair on damaged skin is an unmet need in medicine, Ito said, because of the disfigurement suffered by thousands from trauma, burns, and other injuries. However, her more immediate goal, she said, is to signal mature skin to revert back to its embryonic state so that it can grow new hair follicles, not just on wounded skin, but also on people who have gone bald. Ito said scientists have until now assumed that, as part of the healing process, scarring and collagen buildup in damaged skin were behind its inability to regrow hair. “Now we know that it’s a signalling issue in cells that are very active as we develop in the womb, but less so in mature skin cells as we age,” she said.

The study, published in the journal Nature Communications, may help in the search for better drugs to restore hair growth