Adenosine (topikális)

Detailed overview

Adenosine is a naturally occurring nucleoside involved in cellular energy metabolism and signalling. As a topical agent against hair loss it became established mainly in Japan, where it is treated not as a supplement but as a serious treatment option: the 2017 Japanese dermatology guideline published by Manabe in 2018 discusses it among the treatment options for male and female pattern hair loss. The evidence has a twofold structure. Oura 2008, a double-blind placebo-controlled pilot in Japanese women with female pattern hair loss, showed that adenosine increased the proportion of hairs in the anagen or growth phase and the number of thick hairs. Iwabuchi 2016 confirmed the same endpoint in Caucasian men with androgenetic alopecia, which matters because hair structure and treatment response can differ by ethnicity. Faghihi 2013 performed a direct comparison, measuring a 0.75% adenosine solution against 5% minoxidil in male androgenetic alopecia. The mechanism operates through the dermal papilla cells of the follicle. Adenosine binds receptors on these cells and increases production of fibroblast growth factor 7 (FGF-7, also known as keratinocyte growth factor), which is responsible for prolonging the anagen phase. This mechanism is independent of DHT, so it is not antiandrogenic: adenosine does not target the androgenic cause of hair loss but extends the growth phase. It follows that it may interest those who do not want or cannot tolerate minoxidil or finasteride, and this explains why it is the typical base of minoxidil-free serums.