Category Archives: Johns Hopkins University

Dr. Luis Garza of Johns Hopkins University

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.

This is primarily because he has 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:

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.

Of Mice and Men

Virtually all hair related research at universities, clinics and private labs starts with experimentation in mice or rats. In some cases, they move on to hamsters and macaques.

Per the Foundation for Biomedical Research, 95 percent of all lab animals are mice and rats. I am guessing that the smaller sized mice represent a much higher share of this 95 percent in comparison to the larger sized rats.

During my research for this post, I read that one of the main differences between mice and rats is that while the former are very curious, the latter are fairly cautious. i.e., the smaller rodent is braver (or more foolish) than the larger rodent. When I saw “Rats”, I did not find rats to be particularly cautious. According to that documentary, rats are the most successful species on earth. They will surely outlast us, as will cockroaches.

Successful Hair Growth in Mice and Rats

Since I first started writing this blog, the single biggest pet peeve of most readers as well as myself has been:

Why is hair loss regularly cured in mice and other rodents, but never in humans?

Forget the word “cure”. Even a moderately effective hair loss treatment would be welcome. The countless groundbreaking successes in hair regrowth in mice over the past several decades have never even translated into any major hair loss treatment for humans. This travesty has been going on for way too long.

Mice Growing Hair
Dr. Tsuji’s Famous Mouse Growing Hair.

All we can do is hope than sooner or later, someone like Dr. Tsuji will emulate his success in mice -> to success in humans -> to a final product release. In many cases, positive results in mice and then in small-scale human trials never progress to a final product release due to lack of funding or corporate interest.

However, this should change in the next several years as a number of companies start or complete final Phase 3 clinical human trials for various new hair growth products.

The main reasons researchers like to use mice and rats for their hair loss research work are:

  • Low cost.
  • An abundant and plentiful supply.
  • Small creature size making housing, feeding and maintenance relatively easy.
  • Short 2-3 year lifespan making generational study possible.
  • Mice and humans share about 97.5 percent of their working DNA. Almost as similar as the relationship between humans and the great apes.

Two New Hair Loss Cures in Mice in July 2018

Note: I am a bit uncertain if mouse or rat fur can be compared to human scalp hair more than to human body hair. In humans, scalp hair and body hair often have an inverse relationship.

Mitochondrial Repair and Hair Growth

As a result of the earlier mentioned pet peeve, I initially decided to ignore the biggest hair loss related news story of this month from several weeks ago. Scientists from the University of Alabama (led by Dr. Keshav Singh of Yuva Biosciences) managed to reverse hair loss and skin wrinkling in mice. Actual study findings are here. The scientists managed to reverse mitochondrial dysfunction (which they induced in the first place), which in turn reversed hair loss and wrinkling in mice.

Mitochondria and Hair Growth
Reversal of wrinkles and hair loss after mitochondrial DNA replication is resumed. Credit: University of Alabama.

This news was covered extensively by the global media. I decided to skip writing about these findings, and instead focused on keeping my posts on the important recent developments from Histogen and Cassiopea on the front page of this blog a little longer. Both of these companies are going to complete final Phase 3 trials in humans in the next several years. In contrast, The University of Alabama research might not even ever make it to Phase 1 trials in humans.

Reversal of Fatty Diet Associated Hair Loss and Hair Whitening

However, yesterday came news of yet another major development in regards to scientists curing hair loss in mice. So I finally had to write this post on rodents getting back their hair (and their hair color and their youthful skin) twice in the past two weeks. It is ironic that rodents do not even care one iota about their appearance.

High Fat Diet Hair Mouse
Credit: Johns Hopkins University.

This time, the latest research was in regards to hair loss in mice that was associated with a bad “western” diet high in fat and cholesterol. Actual study findings are here. The cure entails daily ingestion of a pill that the mice will have to remember to take. The compound halts the production of certain types of fats known as glycosphingolipids (GSLs).

The research was undertaken by scientists at Johns Hopkins University (led by Dr. Subroto Chatterjee). One of the interesting quotes in relation to this work was that:

“Current research shows that mice fed a diet high in fat and cholesterol are more likely to have hair discoloration from black to gray to white, extensive hair loss and inflammation of skin exhibited by multiple wounds.”

Long-time readers of this blog will know that this link between bad diet and hair loss has often been blamed for increasing hair loss in Japanese men since the end of World War II. I think that men and women in all countries are losing hair at earlier ages than in past generations. I was never too keen about this diet and hair loss argument, but perhaps there is something to it?