Category Archives: Luis Garza

Dr. Luis Garza of Johns Hopkins University

Update: April 27, 2020

Dermatologist Dr. Luis Garza from John Hopkins Medicine is among the 10 most renowned hair loss researchers in the US. Both the general media and myself have not covered him anywhere near as frequently as we have others. Especially compared to the “Big Three” of Angela Christiano, George Cotsarelis and Ken Washenik.

However, as a hair loss researcher, I respect Dr. Garza more than any other leading scientist. Primarily because he seems to have stuck with one institution for most of his career. And he does not seem to be affiliated with various commercial interests. Dr. Garza is especially well known for his work with PGD2 and hair growth.

Dr. Luis Garza Recent Interview

Yesterday, I discovered a great recent video interview of Dr. Garza with ideaXme’s Ira Pastor. It only had 508 views at the time of writing this post, so was missed by most people. Youtube has a goldmine of such barely viewed content that does not show up when people sort by view count.

At the moment, the below video has 25 thumbs up votes and 0 thumbs down votes. I agree with this percentage. This is the first time that I have seen Dr. Garza on video, which is very surprising to me.

Among the most interesting parts of the below video include:

  • Double-stranded RNA (dsRNA) and its influence on scarless wound healing and hair regeneration.
  • Wounding and hair growth aka wound induced hair neogenesis.
  • Genes involving dsRNA and genes involving skin retinoic acid production are both expressed at higher levels after laser treatment.
  • Organogenesis and limb regeneration to help the wounded.
  • The connection and similarities between hair regeneration, skin regeneration and organ regeneration.
  • Cells have a GPS type homing mechanism that tells them where to go and how to behave.


August 6, 2015

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 among the 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.

Toll-Like Receptor 3 and Double-stranded RNA

Today, Dr. Garza and his team published an important article in the Cell Stem Cell Journal.  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 is encouraging):

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.

PGD2 Inhibitors: The Next Big Trend at Hair Clinics?

Update: January 2020 — South Korea’s Stemore is working on a PGD2 inhibitor hair loss product called SM-003.


Numerous groundbreaking developments have occurred in hair loss cure research during the past few years. Among the most exciting is Kythera Biopharmaceuticals’ Setipiprant prostaglandin D2 (PGD2) antagonist (inhibiting) product.

For a better understanding of the link between male pattern baldness (MPB) and PGD2, this 2014 paper from the famous Dr. Luis Garza and Dr. Ashley Nieves is excellent reading. Also worth reading is this 2012 paper from Dr. Luis Garza, Dr. George Cotsarelis and others.

In the simplest of terms, prostaglandin D2 levels are elevated in balding scalps, and inhibiting PGDcould prevent baldness from progressing. In order to do this, you target the PGD2-GPR44 pathway (since PGD2 binds to the GPR44 receptor).

What excited me even more so than the research behind this subject matter is the following 2015 audio interview with Kythera founder and at-the-time CEO Keith Leonard. When I first heard it, I felt like he really knew what he was talking about and was sincere. Mr. Leonard seemed very excited about the “elegant” science (from Dr. Cotsarelis and his team at the University of Pennsylvania) behind this product.

Unfortunately, it seems like Mr. Leonard is no longer with Kythera. Moreover, when I checked Kythera’s website today, the pages with a listing of board of directors and management were missing. I would not read too much into Mr. Leonard’s departure, as the release of Setipiprant is still at least several years away in a best case scenario. To learn more about Kythera and Setipiprant, read my post from 2015 in its entirety.

Clinic Made PGD2 Inhibition Products to Treat Hair Loss

What made me think about this subject matter this week after several months of forgetting about it was an interesting new article published three days ago coming from India. Apparently a local clinic named “Hairline International Hair and Skin Clinic” is now offering PGD2 inhibitor therapy for hair loss. The article is full of typos, bad science and ads. My immediate reaction is that this Indian clinic’s product is likely to be totally ineffective and a sham.

Nevertheless, this development is not surprising at all considering that so many hair loss forum members have been experimenting with similar homemade products for several years now. So perhaps such a product is not too difficult to manufacture/compound? Even something like topical cetirizine is thought to help androgenetic alopecia via reducing PGD2.

Are we about to see more hair loss clinics offer proprietary products that inhibit PGDor is this just a one-time thing that will spread to very few other places? A decade ago, very few hair loss clinics offered lasers or platelet-rich plasma therapy to treat hair loss, but now both are commonplace worldwide. Can PGD2 inhibition therapy follow a similar path?  With PGDtherapy, I do wonder how much the patent held by Kythera negatively impacts the chances of other competing proprietary products from hair loss clinics becoming popular and legal, especially in the US?

Homemade (“ghetto”) PGD2 Inhibitors to Treat Hair Loss

There is a good chance that Setipiprant will significantly aid patients with androgenetic alopecia. The only problem is that clinical trials for Setipiprant will not be completed for several years. So not surprisingly, many people on hair loss forums are creating their own versions of Setipiprant/PGDinhibitors and testing them, or purchasing them from oftentimes sketchy vendors. The vast majority seem to have tested these “ghetto” products with no groundbreaking results to report. However, as is always the case with such experiments, a majority of people are probably not even remotely correct in getting correct ingredients, dosages, vehicles and more. In any case, I will leave you with some links to the said hair loss forum threads further below.

Also note that I plagiarized the “ghetto” term from “Swisstemples” who I have mentioned on this blog several times before. He has what seems to be an excellent page on his site regarding “The Postaglandin Protocol.”  He also has a page on things to buy and use (where he uses the term “ghetto protocol” that includes some products to combat PGD2. I do not take any responsibility if you do what he suggests and get nasty side effects. I would never try any of this myself unless I had a really good chemist friend.

Note that people use various essentially synonymous terms for the products that they are trying in some of the below links, including “PGD2 receptor antagonist”, “PGD2 blocker”, “PGD2-GPR-44 receptor antagonist” and “CRTH2 receptor antagonist”.

— An excellent poster from the 9th Congress for Hair Research last year  (thanks “Hellouser”) can be found here –> “CRTH2/DP2 Antagonists Reverse Hair Growth Inhibition Caused by PGD2.” Main authors are Cotsarelis, Hsieh, Nace and Zheng.

— 51 page and growing HLT thread titled “dedicated Setipiprant log.”  Seem to be overall negative results, but I have only read 3-4 of those pages.

— BTT thread on homemade  PGDinhibitors.

— HLT thread on whether anyone is still on PGDblockers?

— HLH thread on OC000459, a CRTH2 antagonist. Also see Oxagen.

Ramatroban (a PGDreceptor antagonist) that many people seem to have purchased. I have no idea about safety and legality issues.

— Note that Kane from China was offering his version of Setipiprant in the past, but I do not know the current status.

— Seems of interest regarding CRTH2.

PGD2 Regimen — Cetirizine + Water.

— An interesting recent HLT thread on CRISPR type gene therapy to fix the three single nucleotide polymorphisms (SNPs). Specifically, rs545659, rs634681 and rs7167 have been found to be responsible for this PGD2 sensitivity.

Resvertarol and PGD2?  Not sure about this one.

Quercetin and PGD2  video. Not sure about this one either, but many other hair loss forum posts on this subject.