The results of a new clinical trial published in the journal STEM CELLS Translational Medicine demonstrate how a topical solution made up of stem cells leads to the regrowth of hair for people with a common type of baldness.1
Getting to the root of the problem
Having a head of hair is probably something that many people don't give much of a second thought to. But for individuals experiencing androgenetic alopecia (AGA), also referred to as male or female-pattern baldness, losing one's hair can adversely impact self-esteem, psychological wellbeing and quality of life.
AGA is a complex condition that has genetic, hormonal and environmental roots. It affects approximately 50% of all males and a similar proportion of females, however the pattern of hair loss differs between the sexes. In women, hair often becomes thinner all over the head and the hairline does not recede. Often in women, AGA does not lead to total baldness.
In males, hair loss often occurs in a pattern, beginning above both temples and eventually receding to form an "M" shape. In most cases, AGA progresses to partial or complete baldness.
Unfortunately, there are only a few FDA-approved medications to treat hair loss, and these carry a myriad of associated side effects including a negative impact on sexual functioning. There is therefore a pertinent need to develop anti-hair loss treatments that lack such side effects.
Emerging research has demonstrated the potential application of stem cells, particularly adipose tissue-derived stem cells (ADSCs), in this space. ADSCs are a type of mesenchymal stem cell that secrete several growth hormones that facilitate cell development and proliferation.
As previous research has demonstrated that growth factors such as hepatocyte growth factor, vascular endothelial growth factor, insulin-like growth factor and platelet-derived growth factor increase the size of hair follicles during hair development, scientists have explored whether ADSCs can promote hair growth in men and women with alopecia.2,3 The results of such research have been positive, however, a randomized, placebo-controlled trial of such a therapeutic approach in AGA did not exist – until now.
"Recent studies have shown that ADSCs promote hair growth in both men and women with alopecia. However, no randomized, placebo-controlled trial in humans has explored the effects and safety of adipose-derived stem cell constituent extract (ADSC-CE) in AGA," says Sang Yeoup Lee, M.D., Ph.D., of the Family Medicine Clinic and Research Institute of Convergence of Biomedical Science and Technology, Pusan National University Yangsan Hospital. "We aimed to assess the efficacy and tolerability of ADSC-CE in middle-aged patients with AGA in our study, hypothesizing that it is an effective and safe treatment agent."
A growing area of research
Lee and colleagues conducted a randomized, double-blind, placebo-controlled clinical trial which recruited 38 patients, including 29 men and nine women ages between 18 and 59 years. The participants were required to meet a strict inclusion criterion which specified that they maintained a consistent hair style and did not receive other hair care throughout the 16-week trial. Half of the patients were assigned to an intervention group, who received an ADSC-CE topical solution, and the remaining half were assigned as a control group, receiving a placebo.
The solution provided to the intervention group contained 1% ADSC-CE diluted in distilled water, whereas the placebo group simply received distilled water. Where does one obtain ADSCs from, you ask? The materials for this trial were collected from the adipose tissue of healthy donors that had provided consent to the material being utilized for research or commercial purposes prior to undergoing liposuction. In order to preserve the controls, both solutions were colorless and odorless.
Participants were instructed to apply 2mL of solution to the area in which they experienced hair loss, twice every day for a total of 16 weeks, massaging the solution into their scalp using their fingers. Each subjected visited the research center four times in total throughout the study, and were requested to keep a diary to record when they were using the solution.
To measure whether the solution was significantly impacting hair growth, the scientists measured changes in total hair number and hair thickness as confirmed by close contract photographs using a standardized technique. This was the primary efficacy variable. Photographs were taken at baseline, eight weeks and 16 weeks after using the product. At baseline, participants received a dot tattoo over their scalp to ensure that the photographs were taken at the same spot at each follow up. The secondary efficacy variables of the study included analysis of global photographs of the participants' scalps by an investigator, and self-evaluation of hair growth by the participants.
Hope of a future treatment for hair regrowth
After completing the 16-week study, the intervention group had a significant increase in both hair count and follicle diameter. Mean hair density and thickness increased by 28.1% and 14.2% by 16 weeks, which were 3.95 and 2.25 times those in the control group. In the discussion of the paper, the authors note that "The improvements in the intervention group were quite impressive when compared with results of studies on the efficacy of conventional treatments in AGA."
Whilst these results are promising, the authors note several limitations to the study. When assessing the secondary efficacy outcomes, the researchers found that the improvement score provided by the investigator was higher in the intervention group than the control, but this was not a significant increase. Additionally, the evaluation provided by the subject was lower in the intervention group. The scientists suggest that a contributing factor here could be the study duration, positing the idea that the length of time in which the participants were involved in the trial may not have been sufficient for them to notice a visual improvement. Furthermore, the self-report assessment could have been limited in validity as subjects may have been impacted by their own expectations towards the intervention. A solution to consider going forward could be to ask participants about their expectations regarding the magnitude of improvement at baseline.
Lee adds, "Our findings suggest that the application of the ADSC-CE topical solution has enormous potential as an alternative therapeutic strategy for hair regrowth in patients with AGA, by increasing both hair density and thickness while maintaining adequate treatment safety. The next step should be to conduct similar studies with large and diverse populations in order to confirm the beneficial effects of ADSC-CE on hair growth and elucidate the mechanisms responsible for the action of ADSC-CE in humans."
"For the millions of people who suffer from male-pattern baldness, this small clinical trial offers hope of a future treatment for hair regrowth," says Anthony Atala, M.D., Editor-in-Chief of STEM CELLS Translational Medicine and director of the Wake Forest Institute for Regenerative Medicine. "The topical solution created from proteins secreted by stem cells found in fat tissue proves to be both safe and effective. We look forward to further findings that support this work."
1. Tak, Lee, Cho and Kim. (2020). A randomized, double‐blind, vehicle‐controlled clinical study of hair regeneration using adipose‐derived stem cell constituent extract in androgenetic alopecia. Stem Cells Translational Medicine. DOI: https://doi.org/10.1002/sctm.19-0410.
2. Ramdasi S, Tiwari SK. (2016). Growth factors and cytokines secreted in conditioned media by mesenchymal stem cells-promising possible therapeutic approach for hair regeneration. J Stem Cells. https://www.ncbi.nlm.nih.gov/pubmed/28296872.
3. Lee et al. (2001). Hepatocyte growth factor (HGF) activator expressed in hair follicles is involved in in vitro HGF-dependent hair follicle elongation. J Dermatol Sci. 25:156-163.