RESUMO
BACKGROUND: Androgenetic alopecia (AGA) is common. While topical minoxidil remains the only FDA-approved therapeutic for AGA, its efficacy is limited in stimulating clinically significant hair regrowth over the longer term. Oral minoxidil, which is used off-label, is a promising alternative; however, its effectiveness and underlying mechanisms warrant further investigation. AIMS: To elucidate the site of action and infer the physiological mechanisms underlying therapeutic responses to oral minoxidil in patients with AGA. METHODS: Forty-one patients with AGA underwent 6 months of low-dose oral minoxidil treatment. Minoxidil sulfotransferase (SULT) activity was assayed in plucked scalp hair follicles. The primary outcome was hair growth after low-dose oral minoxidil treatment for a minimum of 6 months, and the secondary outcome was SULT activity in hair follicles. RESULTS: After 6 months of treatment, 26 (63.4%) patients experienced a clinical improvement in alopecia symptoms. The response rate was higher in men (19/26 [73.1%]) than in women (6/15 [40.0%]). Patients with low hair follicle SULT activity demonstrated a higher minoxidil response rate than those with high enzyme activity (85% vs. 43%, p = 0.009). CONCLUSIONS: Our findings indicate that low SULT activity within the hair follicles is associated with a favorable response to oral minoxidil therapy in patients with AGA. Further elucidation of the underlying mechanisms could significantly improve personalized therapeutic approaches through improved patient selection and the rational design of adjuvant treatments.
RESUMO
BACKGROUND: Minoxidil is the only US FDA approved topical drug for the treatment of androgenetic alopecia (AGA). Minoxidil is effective in hair re-growth in 30%-40% of patients and 50% of males. To exert its hair growing effect, minoxidil must be sulfonated in the scalp by the minoxidil sulfotransferase enzyme (SULT1A1). Low scalp SULT1A1 correlates with lack of minoxidil response; thus, supplementing the scalp SULT1A1 with naturally occurring minoxidil sulfotransferase enzymes could potentially improve treatment outcomes in AGA patients. METHODS: In this study, we set to characterize SULT1A1 activity in various plants. RESULTS: From the 10 common botanical extracts we have studied, seven exhibited significant activity toward minoxidil as a substrate; thus, providing a potential novel paradigm to increase minoxidil response with natural supplements. CONCLUSION: To the best of our knowledge, this is the first study to characterize naturally occurring minoxidil sulfotransferase enzymes in plants.