Category Archives: Michael Rendl

Dermal Sheath Contraction, Lymphatic System and Hair Loss

There were three important developments in the world of hair loss in December 2019 that I did not cover in separate posts. This is becasue all of them entail findings that are yet to translate into any kind of clinical trials.

Dermal Sheath Contraction and Hair Loss

Dr. Michael Rendl and his team at the Icahn School of Medicine in New York discovered that preventing the dermal sheath smooth muscle from contracting could stop hair loss. In future, a drug could prevent such muscle contraction and one would never shed hair.

The best way to avoid androgenetic alopecia (AGA) is to stop hair from falling out in the first place. This treatment of blocking contraction of the sheath muscle has the potential to do just that in the future. Actual study here. The scientists discovered that the dermal sheath’s function is to contract and push up the hair shaft and pull up the dermal papilla cells (towards the stem cells).

Lymphatic System Involved in Hair Loss

Another renowned hair loss researcher from New York that I have covered in the past is Dr. Elaine Fuchs. In December, her team at Rockefeller University found that the lymphatic system plays a key role in hair regeneration.

Hair follicle stem cells control the behavior of lymphatic capillaries. This discovery can lead to new therapeutic targets for lymph-related conditions, including wound-healing defects and hair loss. Actual study here.

CRISPR/Cas9 Delivery System for AGA

Also in December 2019, South Korean scientists published an important paper on using CRISPR/Cas9 to treat androgenetic alopecia. They used ultrasound delivery and activation of nanoliposomal particles. The researchers successfully transferred protein constructs into hair follicle dermal papilla cells.

There are very few studies on the use of CRISPR and gene therapy (or gene modification) to treat hair loss. Hopefully, this will start to change in the near future. Most scientists are interested in using CRISPR to treat medical problems rather than cosmetic ones. It will always be easier to get government approval for the former rather than the latter.

Dr. Michael Rendl — Mesenchymal Control of Hair Follicle Growth

On this blog, I have in the past discussed various dermatological associations and non-profits, including several important ones in the United States such as the American Academy of Dermatology (AAD) and Advancing Innovation in Dermatology (AID).  A third one called the Society for Investigative Dermatology (SID) recently had its 75th annual meeting on May 11th, 2016.

On SID’s youtube channel, you can find a number of the video presentations from this meeting, including a few that discuss hair in at least part of the presentation.  On SID’s website they have a summary list of presentations that includes quite a few involving hair, but none of those videos seem to be available as yet.  Hopefully they will make more of them publicly available soon assuming they videotaped all the presentations.

Dr. Michael Rendl

For now, the most relevant video when it comes to our cause is a presentation by Dr. Michael Rendl that I have embedded below.  On this blog, I have discussed Dr. Rendl’s work several times in the past, including in this post about his Rendl lab.  The below video is highly interesting, especially when it comes to the crucial dermal papilla cell and its induction of hair growth.  I did not realize how complicated this process is and how researchers still have so many uncertainties about the various signals, transcription factors, pathways and processes that lead to the dermal papilla inducing hair growth.

The parts on gene expression, RNA deep-sequencing and CRISPR-mediated genome editing are also very interesting, especially since CRISPR has been in the news so much in the past year (and it now seems inevitable that adult humans will be able to have their genes edited in the future).  A lot of the content is very technical and way above my head.

Kudos to Dr. Rendl for creating the hair-GEL (gene expression library) website for sharing this crucial information with everyone for free. It is too bad that Dr. Rendl is totally bald and seems to be very comfortable with that look.