The hair regeneration industry is replete with buzzwords – the buzzword du jour: stem cell. It has a kind of “health halo.” It rolls off the tongues of its users with a medical-like tone and subtle mystery. We know we’ve heard the phrase, and think we should know what that is, and why we need to know. Many are reluctant to admit a lack of sophistication in their understanding.
In advertisements for hair regeneration we see “stem cell” associated with, “Get back to doing what you love,” “Stem cell breakthrough,” “Stem cell therapy plus,” “Stem cells bring hope,” and “Restore your confidence [with stem cells.]”
The earliest stem cells identified were obtained from living embryos. Their use was, and is, a matter of fierce debate – the fate of living embryos, adequately nurtured, being living children. It has been determined, however, that stem cells are present in all multi-celled organisms, including adult forms. They multiply by cell division. Stem cells can differentiate into many types of tissue, often the type of tissue in their current environment. They can contribute to tissue regeneration, such as wound healing.
Adult stem cells are currently the subject of biologic and biomedical research. They are found in blood-cell production, muscle, liver, nervous-system, and epidermis-generated structures: feathers, teeth, and hair follicles.
Hair follicle stem cells are grouped in a niche called “bulge,” located between the openings of sebaceous (oil) glands and attachments of arrector pili muscle cells (which cause “goose-bumps.”) Bulge stem cells are pluri-potent, and multiply rapidly. Hair follicle stem cells are long-lived, producing hair throughout a person’s lifetime.
Hair growth occurs in cycles with three phases. At any given time, hairs will be found in all three stages of growth and shedding: anagen, catagen, and telogen.
Anagen is the active phase of hair growth. The cells in the root of the hair are dividing rapidly, forming a new hair; it pushes the club hair (a strand leaving the anagen phase of growth) up the follicle and eventually out. Each hair stays in this active phase of growth for two to six years.
The catagen phase is transitional; about 3% of all hairs are in this phase at any time. The phase lasts for two to three weeks. Growth stops, the outer root sheath shrinks, and attaches to the root of the hair, now called a club hair.
Telogen is the resting phase of the hair growth cycle, accounting for 6% to 8% of all hairs. It lasts for about 100 days for hairs on the scalp. Normal, daily, hair loss is 50-100 telogen-phase hairs.
Hair follicle stem cells are usually quiescent (inactive), but quickly activate at the start of hair’s cyclical growth – the anagen phase. Hair follicle stem cells are regulated by many factors. When they fail to activate, hair loss occurs.
In August 2017, it was reported that researchers at the University of California – Los Angeles Health Sciences had discovered a new way to activate the stem cells in hair follicles to make hair grow. Scientists Heather Christofk and William Lowry were the leaders of the study: Lactate dehydrogenase activity drives hair follicle stem cell activation, published in Nature Cell Biology, 2017.
The team identified two drugs that, when applied to the skin of mice, influenced hair follicle stem cells in distinct ways. They affected lactate production, a metabolic product that could accelerate hair follicle stem cell activation. Lowry, a professor of molecular, cell and developmental biology, said, “Once we saw how altering lactate production in the mice influenced hair growth, it led us to look for potential drugs that could be applied to the skin and have the same effect. The first drug, called RCGD423, the second, called UK5099, both have provisional patents.
“Through this study, we gained a lot of interesting insight into new ways to activate stem cells,” said Aimee Flores, a predoctoral trainee in Lowry’s lab and first author of the study. “The idea of using drugs to stimulate hair growth through hair follicle stem cells is very promising, given how many millions of people, both men and women, deal with hair loss. I think we’ve only just begun to understand the critical role metabolism plays in hair growth and stem cells in general; I’m looking forward to the potential application of these new findings for hair loss and beyond.”
The experimental drugs described above were used in preclinical tests only and have not been tested in humans or approved by the Food and Drug Administration (FDA) and the TGA as safe and effective for use in humans.
As of this writing, there are no substances or procedures, in regard to stem cells and the regeneration of human hair, or associated with human hair loss, that have been approved by the FDA and TGA. Studies of hair follicle stem cells have been performed on mice. There are, however, significant differences between mouse and human hair follicle stem cells. Results from studies in mice must be confirmed in humans.
Ashley & Martin Medical Hair Centres do not currently use stem cells, or stem cell activation, in their treatment protocols. Their clients enjoy a success rate of 98 percent.
Research has identified a pattern in the social attitudes toward buzzwords, and their activity. They emerge in a “hype cycle,” which quickly reaches a “peak of inflated expectations.” Just as quickly, there is a “trough of disillusionment.” Eventually, a slow “slope of enlightenment” reaches a “plateau of productivity.”
Each consumer, and each care provider, decide to jump on board the hype cycle, or choose, possibly, the slower slope, or plateau. Prudence and patience can be valuable safeguards.
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