Hair Restoration Blog

DHT and Hair Growth Inhibition in Mice

There is new research about hair growth and the effect of DHT which indicates more details of DHT (Dihydrotestosterone) mechanism on hair growth in mice through inhibition of insulin-like growth factor-1 in dermal papillae cells of hair.  The study results are published by Growth Hormone Research Society (Zhao et al.).
The researchers showed IGF-I [Insulin-like growth factor-I (IGF-I)] present in some hair follicle stem cells (dermal papillae) was increased following the stimulation of their sensory nerves in mice.

We know DHT inhibits hair growth by negatively modulating growth regulations.  The researchers found DHT blocks the release of calcitonin gene-related peptide (CGRP).  They noticed an increase in the IGF-I and proteins which are being made from that effect.  They demonstrated the administration of DHT for three weeks lowers the levels of CGRP, IGF-I AND IGF-I mRNA in the skin of mice. The number of growing hairs was decreased and the re-growth of hair follicles was blocked after the administration of DHT to those mice. Observations of this sort makes clear DHT causes its anti-growth effects on hair through decreasing IGF-I in dermal papillae hair cells.

These new research reports on hair, growth factors, and hair stem cells will lead us in the direction of finding more efficient ways for treating human hair loss in the future.

There is a newly published article where the authors wrote about reconstituting skin from stem cells. This process, explained in the article, requires hair stem cells which are capable of making new skin, including hair, and other skin appendages.

The authors discuss that they have developed a simplified procedure that could modulate, or adjust, the hair formation ability of candidate stem cells. Based on their observations, the formed hair follicles could cycle and regenerate, and the reconstituted skin can heal after injury. These samples were evaluated one year after skin transplant, and they were in good condition.

Hair stem cell is a very hot topic in regenerative medicine and scientists hope they can make other tissues and organs from pluripotential cells that can develop into different cell lineages. We at US Hair Restoration have also recently published an article (Towards expansion of human hair follicle stem cells in vitro) that sheds light on another angle of hair stem cell research and can pave the way for future hair multiplication (also known as hair cloning). Hair multiplication has  great potential of being a medical treatment for hair loss in the future.

More information on this research can be found in the newly published article  in the Tissue Engineering: Part C, Methods on hair multiplication through multiplication of hair stem cells. The articles is titled “A simplified procedure to reconstitute hair-producing skin” by Lee, et al. from Division of Plastic Surgery, Keck School of Medicine, University of Southern California, Los Angeles, California.

Q:

Is Hair cloning or multiplication being done anywhere yet?

A:

Hair cloning or multiplication has been in the news in the last few years. I prefer to use the term hair multiplication, rather than cloning because cloning refers to production of genetically identical organisms. Dolly the most celebrated sheep was the product of first cloning. When it comes to hair, we do not really clone the cells, but we culture them and try to get a whole organism from cultured cells. Unfortunately the process of culturing hair follicle cells has not been as simple as some other tissues in human body. The complexity of hair physiology is due to participation of many different stem cells in development of each hair follicle. In this process, we do not multiply genetic material or DNA of cells.

Hair cloning news

Hair multiplication if become a reality could bring about a great opportunity for bald people with violated donor scalp who cannot be good candidates for hair transplantation with current techniques. Despite our enthusiasm about hair multiplication, hair cloning news in last few years has not been filled with many success stories.

Hair cloning 2007

Year 2006 intercytex company announced that they are going to start phase 3 of hair multiplication study soon. Hair cloning has been in the news and many people are eagerly following that news to see when and how they can get a full head of hair using hair cloning techniques. Unfortunately, cloning hair has not been going that well and in last few years we only had limited research results on hair multiplication in animal models and in human. Here is the question that people usually ask me: Is hair cloning being done anywhere yet? And my answer usually is: Not except on experimental levels. Several investigations are in process on hair multiplication field and hair stem cell research.

Hair cloning 2008

Hair multiplication or as people call it hair cloning is a method that allows us to culture hair follicles and multiply it so we can increase the final number of hairs. So far, we know that it is doable on animals, and there are some reports of its feasibility on human volunteers. Safety has been one of the biggest questions on any research involved with stem cells. Stimulating growth of stem cells has always raised the flag for possible tumor formation. In year 2008, we should witness some results of the phase 3 studies on the procedure. During this year or in next few years, we should have a better understanding of the effectiveness and safety of hair multiplication. I know many of my patients are following hair cloning news carefully. Unfortunately, hair multiplication news has not been very fruitful in last year, but the process is complex and one way or another it will become clear in next few years that we can or cannot use hair multiplication methods in hair restoration surgeries.