PAOLO asked: "Hi Dr.LEE, i'd like to know the role of cytochrome P 450 aromatase in androgenetic alopecia and how Ketoconazole works as a treatment for male pattern baldness. thanks a lot."
Dr Richard Lee, MD answered: "In the human body, androgens can be metabolized to estrogens by the cytochrome P-450-aromatase enzyme. Drs Price and Sawaya have identified differing concentrations of androgen metabolizing enzymes and androgen receptors in hair follicles from women compared to men and they hypothesize these differences are what makes the pattern of female hair loss different from that of male pattern baldness. They found that cytochrome P-450-aromatase content was up to six times more concentrated in women's frontal hair follicles compared to men's frontal hair follicles. They particularly note that the aromatase enzyme is present in greater concentrations at the back of the scalp and less so at the front in women whereas men have only small amounts of aromatase present in any region of their scalp. Women had around 3 times less 5-alpha reductase (type I or type II) enzyme in their frontal hair follicles compared to men. Conversely, androgen receptor content in frontal hair follicles from men is 40% higher than for hair follicles from women. These differences between men and women most likely account for the overt clinical differences in patterns of hair loss and strongly suggest that cytochrome P-450-aromatase with the conversion of androgens into estrogens is a protective device for the hair follicles. Technically, ketoconazole is an oral antifungal agent of the imidazole class, which contains two nitrogen atoms in the five-membered azole ring. The primary mechanism of action of ketoconazole is the inhibition of sterol 14-a-dimethylase, a microsomal cytochrome P450-dependent enzyme system. Ketoconazole thus impairs the biosynthesis of ergosterol, which is one of the essential steps in the synthesis of testosterone and, subsequently, DHT. DHT is the culprit that initiates the chain of events resulting in atrophy of the hair follicles when it attaches to the androgen receptor sites on the hair follicle."
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i'd been kinda slackin on my nizoral, but i'm definitely bumping it back up to every other day. I'm sure you all knew this already, but i guess i just never picked up on it, for all you newbies, don't forget the nizoral!!! 