Società Italiana di Tricologia
Giornale Italiano di Tricologia
Does Female Androgenetic Alopecia really exist ?
Takayasu S., Adachi K.: "The conversion of testosterone to 17 beta-hydroxy 5 alfa-androstane 3-one (dihydrotestosterone) by human hair follicles" J Clin Endocr Metab1972; 34: 1098. Wilson J.D., Walker J.D.: "The conversion of testosterone to 5 alfa androstan 17 beta-ol-3-one (dihydrotestosterone) by skin slice of man" J Clin Invest1969; 48: 371.
or… Low Local Estrone Alopecia: Alopecia caused by insufficient local follicular estrone activity. Andrea Marliani MD Firenze Two essential intrafollicolar hormones regulate hair cycles: diidrotestosterone and estrone. Diidrotestosterone reduces adenylcyclase activity so that the follicle turns into catagen and the hair becomes telogen. Estrone increases adenylcyclase activity, and thus maintains the mitoses of the matrix, and the duration of the anagen. It also activates the staminal cells in the early stages of the anagen phase. Today, it is usual to accept that male androgenetica alopecia is associated with an increase in 5-alpha reductase activity which, genetically, leads to higher levels of diidrotestosteron but this has been studied mainly, if not exclusively, in males. The results obtained have then been referred to women patients, which to my mind is not appropriate and that is why there is talk of Female Androgenetic Alopecia (FAGA). But to give a diagnosis of Androgenetic Alopecia, there are two essential “sine qua non” conditions:
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