Immunohistochemical study of ACTH and alpha-MSH in vitiligo patients successfully treated with a sex steroid-thyroid hormone mixture.

We previously reported that a sex steroid-thyroid hormone (Metharmon-F; MF, 2 tablets daily) was a potent drug for treatment of vitiligo. Using five patients with generalized vitiligo who were successfully treated with oral administration of MF, we performed an immunohistochemical analysis to elucidate its action mechanism at the cellular level. Histopathologically, the repigmented skin after the treatment showed increased numbers of melanocytes and melanin granules. Immunohistochemically, there was little significant difference between the depigmented lesions before treatment and the repigmented lesion after treatment in terms of the reactivity to adrenocorticotropic hormone (ACTH) and alpha-melanocyte-stimulating hormone (alpha-MSH) in keratinocytes. The immunoreactivity to ACTH in melanocytes both before and after the treatment was minimal, but alpha-MSH in melanocytes became much stronger after the treatment, than before the treatment. The efficacy of MF in treatment of vitiligo was proven to be due to the stimulatory effect of melanocyte proliferation and melanin production via alpha-MSH.