RESUMO
BACKGROUND: Androgens influence the growth of terminal hair. The dermal papilla contains androgen receptors and the enzymes 5-alpha-reductase types 1 and 2. Both of these enzymes convert testosterone to the more active androgen, 5-alpha-dihydrotestosterone. The male distribution pattern of terminal hair in females is termed hirsutism. It is most common among women with hyperandrogenism; however, it may also affect patients with normal androgen levels (idiopathic hirsutism). OBJECTIVES: The aim of this study was to assess the expression of 5-alpha-reductase types 1 and 2 mRNA in dermal papillae from the lower abdominal skin in women with hirsutism. METHODS: The study included 42 subjects, 24 with a diagnosis of polycystic ovary syndrome (PCOS) and 18 with idiopathic hirsutism (IH). In all patients, free serum testosterone was measured. RESULTS: The mean +/- SD concentration of free serum testosterone was 7.2 +/-5.3 pmol/L in the total group of patients, 10.8 +/- 4.0 pmol/L in patients with PCOS, and 2.5 +/- 1.7 pmol/L in patients with IH. Quantitative analysis was then performed for the mRNA of 5-alpha-reductase types 1 and 2, both of which were found within the dermal papillae from the lower abdominal skin region. The number of mRNA copies/microg of total RNA for 5-alpha-reductase type 1 was statistically significantly higher than that for type 2 in both groups of examined patients. We also demonstrated a positive correlation between the number of mRNA copies/microg of total RNA for 5-alpha-reductase types 1 and 2 and the concentration of free serum testosterone in women with PCOS and IH. Considering all patients together, we found a positive correlation between the number of mRNA copies/microg of total RNA for 5-alpha-reductase type 2 and the concentration of free serum testosterone. There was also a tendency towards a positive correlation between the number of mRNA copies/microg of total RNA for 5-alpha-reductase type 1 and the concentration of free serum testosterone. CONCLUSION: The results of our study suggest that testosterone increases expression of 5-alpha-reductase types 1 and 2 in dermal papillae from the lower abdominal region in patients with hirsutism.
