Hair loss can be caused by several different conditions, including androgenetic alopecia, alopecia areata, and scarring alopecia. Current strategies to prevent hair loss and restore hair include two FDA-approved drug therapies (finasteride and minoxidil) and hair transplants, although other treatment options such as laser light therapy and alternative treatments (e.g. pumpkin seed oil and rosemary oil) may be used in some cases. Stem cell therapies are increasingly being discussed as possible alternatives for hair loss treatment.(1)
Stem cells are young cells that can self-renew and develop into one of many different types of cells (e.g., fat, heart, or brain cells). Cells that have not yet differentiated into fat cells, also called pre-adipocytes or adipose-derived stem cells (ASCs) are thought to be involved in hair regeneration. For example, young fat cells play a role in activating hair stem cells while older cells regulate their activity.(2) The hair growth cycle is closely tied to fat cells; for example, the fat between layers in the skin is thicker when the hair follicle is in a growth phase (anagen) than when the hair follicle is in resting phase (telogen).(2) These fat cells secrete growth factors that can increase blood flow to the hair cells, which helps regenerate hair follicles.(2)
There is currently no conclusive data demonstrating that ASCs can increase hair growth but some studies in mice have shown that they are involved in forming hair follicles, blood vessels, and fat tissue.(2) Furthermore, a recent study examined the use of ASCs in 22 male and female patients with hair loss by administering a solution containing ASCs through an injection in the scalp every 3-5 weeks for 6 doses.(3) The number of hairs increased in both men and women (by 29 hairs and 16 hairs, respectively) within a spot circled on the scalp before treatment. In the same study, 10 patients were injected on one side of their scalp for the same amount of time. Although hair growth on the entire head was observed, more hair grew on the side where the injection was given. The ASC injection was effective in both patients taking finasteride and those not taking it, although the combination of finasteride and injection was thought to be preferable.
Another study examined ASC use in 27 female patients with pattern hair loss.(4) The ASCs were given every week for 12 weeks using a micro-needle roller. After 12 weeks, they found a 16% increase in average hair density (from an average of 105.4 hairs to 122.7 hairs /cm2) and an 11% increase in average hair thickness.
ASCs can be obtained fairly simply, through liposuction and can be increased using laboratory cultures. Although further research needs to be done in order to understand how these stem cells are involved in hair regeneration before they are used clinically, it is an interesting potential avenue for therapy in the future.
Article by: M.A. MacLeod, MSc., Mediprobe Research Inc.
References
- Santos Z, Avci P, Hamblin MR. Drug discovery for alopecia: gone today, hair tomorrow. Expert Opin Drug Discov. 2015 Mar;10(3):269–92.
- Zhang P, Kling RE, Ravuri SK, Kokai LE, Rubin JP, Chai J-K, et al. A review of adipocyte lineage cells and dermal papilla cells in hair follicle regeneration. J Tissue Eng. 2014;5:2041731414556850.
- Fukuoka H, Suga H. Hair Regeneration Treatment Using Adipose-Derived Stem Cell Conditioned Medium: Follow-up With Trichograms. Eplasty. 2015;15:e10.
- Shin H, Ryu HH, Kwon O, Park B-S, Jo SJ. Clinical use of conditioned media of adipose tissue-derived stem cells in female pattern hair loss: a retrospective case series study. Int J Dermatol. 2015 Jun;54(6):730–5.
