Won-Soo Lee, Hyung Jin Ahn, Young Hee Kim
Department of Dermatology. Yonsei University Wonju College of Medicine, Wonju. Korea
Study Information and Results:
Capsaicin induces the release of substance P(SP) which is believed to play an important role in murine hair growth and cycle. Minoxidil, the only approved topical hair drug having direct hair growth effect, has therapeutic limitation because it stimulates mainly vellus hair regrowth, not thick coarse terminal hairs.
So, we hypothesize that combined use of capsaicin and minoxidil may exert positive effects in terms of hair growth than minoxidil alone. We evaluated the effects of coapplication of capsaicin and minoxidil on the hair growth and cycle, compared with application of capsaicin or minoxidil alone. We induced the anagen phase of the hair of back skin of ICR mice by depilation.
We divided the mice into 4 groups, i.e., control group, capsaicin group, minoxidil group, and coapplied group. And then, we examined the hair growth macroscopically, and the percentage of the area of hair regrowth by image analysis using phototrichogram at the 0, the 5th, 10th, 15th, 20th, 25th, and 30th day. Also we examined the morphologic changes of hair follicles and subcutis, and the number of mast cells by microscopy, andmethyl-3Hthymidine uptake by scintillation counter.
In this study, we observed that capsaicin can not only induce the anagen phase quickly, but also sustain constant effect on the linear hair growth. Minoxidil also induced the anagen phase fast, and prolonged the anagen phase of the hair cycle. Therefore, it is concluded that the coapplication of capsaicin and minoxidil can grow hair quickly and steadily.
Hypothesis was developed that Capsaicin in conjunction with Minoxidil might yield better results than the typically vellus (thin, as opposed to thick and coarse) hairs that Minoxidil is able to produce. Conclusions on this study seem a little confusing. They sought to determine the effect of both treatments in combination, and had a Minoxidil-only, Capasaicin-only, and Combination group of subjects. Then they say that Capsaicin quickly induced anagen, as did Minoxidil. In this abstract they don’t seem to have elaborated on the effect of the combination treatment.