Due to a proliferation of repetitive negative and pessimistic comments from some blog readers recently, I will start of this post with two caveats that need not be repeated in the comments via sarcastic one liners as has become the norm lately:-(
- The below findings might not be as applicable to androgenic alopecia (aka male pattern baldness — MPB) as they are to scarring and other forms of alopecia involving damaged hair follicles. However, there is still some potential that these findings and any new medication that arises from them will also benefit androgenic alopecia patients. Dr. Garza rightfully warns MPB sufferers to not get their hopes up, but he has not entirely ruled out any benefit.
- Yes the work was largely done on mice. Not worth repeating this in the comments if you make one.
I have discussed Dr. Luis Garza’s work on this blog several times before, mostly related to his important findings about prostaglandin D2 (PGD2) and its impact on hair growth. Dr. Garza is in all likelihood among the ten most accomplished and respected hair loss researchers in the world. He works at the Johns Hopkins University School of Medicine. In fact he has his own named facility there called the Garza Laboratory. The list of projects that his team is currently working on includes several focused on hair growth.
Today, Dr. Garza and his team published an important article in the Cell Stem Cell Journal. Basically they have found that a protein called toll-like receptor 3 (TLR3) plays a crucial role in the regeneration of damaged skin and hair follicles. TLR3 activates various genes (IL6 and STAT3) and signaling pathways (Wnt and Shh) that are involved in hair regeneration.
It is common knowledge that damaged mammalian skin releases double-stranded RNA (dsRNA), which is then sensed by TLR3. Besides the previously mentioned regeneration of damaged skin and hair follicles, TLR2 also plays a role in activating the immune system.
While most of the main work was done on mice, in a side experiment on humans, the Garza team found that “the expression of TLR3 was five times higher in scratched human skin cell samples compared to healthy skin cell samples.”
The Garza team also found that adding synthetic synthetic dsRNA to mouse skin wounds led to a greater number of regenerated follicles.
My two favorite quotes from Dr. Garza in the article:
It has long been known that skin damage can trigger regeneration.
The clinical translation of this work is promising because work has already started, says Garza. Drug companies are already developing products to activate TLR3 to trigger the immune system, and these same products could be tested to promote regeneration.
My least favorite quote from Dr. Garza in the article (although the “might” in there makes me happier):
He also made clear that the information might not be as applicable to conditions unrelated to scarring or to those whose hair follicles are lost from male pattern baldness.