In yet another mouse-experiment (some day, scientists really are going to create Pinky and the Brain, or Stuart Little), it has been demonstrated that the skin of animals that have been wounded can naturally regenerate hair follicles, according to researchers at the University of Pennsylvania and as reported by HealthDay.
“The dogma was that when you’re born, you’re stuck with the number of hair follicles that you have. We’re amazed that we’re getting follicles to form,” says study co-author Dr. George Cotsarelis, director of the university’s Hair and Scalp Clinic.
In human beings, when one of your approximately 100,000 hair follicles that you’re born with dies, it cannot come back to life, or so the story has always gone. Scientists have for a long time take it for granted that mammalian hair follicles, period, were a non-renewable resource. But now that notion is being challenged. Something in the genes of mice clearly gives the command to grow new hair follicles as skin recovers from a wound.
Scientists were able to isolate the hair follicle growth gene in the mice, called Wnt, and were successful in switching it on or off to stop or stimulate hair growth in the mice.
“This provides a window for manipulation of hair follicle neogenesis … and treatments for wounds, hair loss and other degenerative diseases,” writes the university research team.
Cotsarelis says, “You’re getting the clock to go back to where it was at birth. [This discovery could] lead to a better understanding of regeneration that might be important for treating wounds and larger sorts of injuries down the road…The follicle is a small organ, a mini-organ. If you can figure out how to regenerate the follicle, you also have a better idea about how to regenerate a finger or a limb.”
Professor Cheng-Ming Chuong, a pathologist at the University of Southern California, who published a commentary in the science journal Nature to accompany the research report, writes, “The new hair follicles grew, passed through the hair cycle, and eventually became indistinguishable from neighbouring hair. These unexpected findings could change our current understanding of repair and regeneration in adult mammals… Regenerative medicine promises to identify natural healing powers and a shift from repair to regeneration. By simply altering the environment of stem cells during wound healing, future wounds might heal with appendages reformed.”
Cotsarelis has co-founded a company called Follica, which has licensed technology to develop hair-restoration treatments. Dr. Andrzej A. Dlugosz, a professor of dermatology at the University of Michigan who is familiar with the study, says, “There are many types of hair loss, and some of these can be emotionally devastating. Developing effective ways to restore hair can do a lot of good for patients in terms of their general well-being.”
However, the researchers and commentators point out that human skin does not heal exactly the same way as mouse skin, and more development of the genetic therapy to get the same hair follicle regrowth in humans would be necessary.
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