Is idiopathic hirsutism (IH) really idiopathic? mRNA expressions of skin steroidogenic enzymes in women with IH

Abstract

Objective: Hirsutism results from hyperandrogenemia and/or exaggerated androgen responsiveness. Among various causes of hirsutism, some patients do not exhibit androgen excess which is called idiopathic hirsutism (IH). The pathogenesis of IH could not so far be clearly established. Design: To investigate the mRNA expression of aromatase enzyme and the other enzymes having functional roles in the steroidogenic pathway, in freshly obtained skin tissue from subumbilical skin and the arm of the patients with IH and healthy women. Methods: Twenty-one women with IH and 15 healthy women were included in the study. We aimed to determine mRNA expressions of genes associated with local androgen synthesis and metabolism (CYP11A1, STS, CYP19A1, SRD5A1, SRD5A2, HSD3B1, AR, COMT, ESR1, ESR2, HSD3B2, CYP17A1, SULT2A1, SULT1E1, HSD17B2, IL6, TGFB1, TNFA) from skin biopsy and blood samples of patients with IH and the data compared with healthy subjects. Results: Patients with IH exhibit significantly lower interleukin 6 (IL6) mRNA expression and higher steroid sulphatase (STS) and hydroxysteroid (17beta) dehydrogenase 2 (HSD17B2), gene mRNA expression, respectively, in the subumbilical region skin biopsies. Similarly, patients with IH exhibit significantly lower IL6 mRNA expression and higher STS and HSD17B2 gene mRNA expression, respectively, in the arm skin compared to healthy women's subumbilical region. Conclusions: In both arm and subumbilical skin biopsy of patients with IH, we observed an up-regulation of HSD17B2 and STS, decreased IL6 mRNA expression, probably determining an increase in the local amount of active androgens, which could then be used as substrate for other androgen metabolic routes.