Miniaturized human hair follicle shows concentration of Prostaglandin D2 (in green). Credit: Garza and Cotsarelis/Penn Medicine)
Researchers at the University of Pennsylvania, who were investigating the biological causes of androgenetic alopecia or common genetic hair loss, have discovered that levels of a certain inhibitor protein, called Prostaglandin D2 (PD2), are elevated in bald areas on the scalp. This discovery could be an important breakthrough in developing a medical hair loss treatment that regulates the production of the protein, or one that blocks it from attaching to its receptor protein.
Prostaglandins are a family of proteins that have a wide range of functions, including controlling cell growth and constricting and dilating muscle tissue. According to an article in ScienceDaily, the researchers had previously found evidence that something was inhibiting hair growth, but they did not expect to find prostaglandins involved in the miniaturization of hair follicles:
“Our findings were unexpected, as prostaglandins haven’t been thought about in relation to hair loss, yet it made sense that there was an inhibitor of hair growth, based on our earlier work looking at hair follicle stem cells,” said George Cotsarelis, MD, chair and professor of Dermatology, and senior author on the studies.
In men with androgenetic alopecia, Prostaglandin D2 was found to be three times higher in bald scalp tissue versus areas of the scalp with hair. Additionally, when hair follicles in a laboratory culture were treated with PD2, the hairs were significantly shorter than non-treated ones. A derivative of PD2, called 15-dPGJ2, was found to completely inhibit hair growth.
The receptor protein that is active with both prostaglandins, called GPR44, may hold the key to limiting the effects of PD2 and, therefore, in regulating hair loss in both men and women. While the study looked only at men, the GPR44 receptor protein exists in women as well. So, theoretically, a topical hair loss treatment may be developed that would prevent or limit thinning or hair loss in both sexes.Posted by