Comparison of steroidogenic pathways among normoandrogenic and hyperandrogenic polycystic ovary syndrome patients and normal cycling women

Abstract

Aim: To compare the corticosteroidogenic enzyme activities between normal cycling non-polycystic ovary syndrome (PCOS), and normoandrogenic PCOS (NA-PCOS) and hyperandrogenic PCOS (HA-PCOS) patients.

Methods: This cohort study was conducted at Julio Muller University Hospital and Tropical Institute of Reproductive Medicine and Menopause, and enrolled 114 non-PCOS women and 355 PCOS patients. The steroidogenic enzyme activities were measured using the serum steroid product/precursor molar ratio.

Results: In the Δ5 pathway the 17,20 lyase activity was equally low in the NA-PCOS and HA-PCOS women compared with the non-PCOS women (P < 0.01 and P < 0.001, respectively). In the Δ4 pathway, the 17,20 lyase activity was higher only in the HA-PCOS group (P < 0.001). The 17-hydroxylase activity was the same in PCOS and non-PCOS subjects (P > 0.05). The 3β-hydroxysteroid dehydrogenase II (3β-HSDII) activity was higher in the conversion of dehydroepiandrosterone into androstenedione in the HA-PCOS than in the NA-PCOS (P < 0.05) and the non-PCOS patients (P < 0.01). The aromatase activity was lower in the HA-PCOS than in the NA-PCOS (P < 0.05) patients and non-PCOS subjects (P < 0.01). In HA-PCOS subjects, the 17,20 lyase activity was related to insulin, estradiol, total testosterone concentrations and free androgen index in the Δ5 pathway. 3β-HSDII showed weak correlation with estradiol in the HA-PCOS group. Anthropometric parameters had little impact, if any, on the steroidogenic enzyme activities.

Conclusion: The NA-PCOS and HA-PCOS patients demonstrated different enzyme activities, and the results provided new directions for future studies including PCOS patients with different phenotypes.

Keywords: adrenal stimulation; enzyme activity; hyperandrogenism; polycystic ovary syndrome; steroidogenesis.