ALTERED EXPRESSION OF OVARIAN STEROIDOGENIC ENZYMES AVOIDS THE PRESENCE OF A SELECTABLE FOLLICLE IN ANOVULATORY WOMEN WITH POLYCYSTIC OVARY SYNDROME

VALERIA SANDER; MARIA BELEN HAPON; EDUARDO LOMBARDI; GRACIELA ALMA JAHN; ALICIA BEATRIZ MOTTA

San Salvador de Bahia, Brasil

Congreso; Simposio Mundial de Ginecologia Endócrina y V Congreso Brasilero de Ginecologia Endócrina; 2009

Asociacion Brasilera de Ginecologia Endocrina (SOBRAGE) y Asociacion Internacional de Ginecologia Endocrina (ISGE)

The loss of a dominant follicle to ovulate is a common feature of Polycystic Ovary Syndrome (PCOS). In a previous work we found that anovulatory PCOS women have lower progesterone and estradiol concentrations and increased prostaglandin F2alpha (luteolytic prostaglandin) in their ovarian follicular fluid. The objective of this work was to determine which steps in the cascade of ovarian steroidogenesis are altered in PCOS patients by evaluating mRNA expression of ovarian steroidogenic enzymes by RT-PCR. We also evaluated mRNA and protein expression of ciclooxygenaseII (COXII, main enzyme of prostaglandin synthesis). Samples of ovarian follicles were collected after women signed a written consent. The control group (n = 14) consisted in women underwent laparoscopy for diagnosis of non-ovarian pathology and PCOS group in women with PCOS (n = 12). Results: StaR and 20-HSD mRNA levels were increased (0.78+0.1 vs. 0.24+0.1 and 0.385+0.06 vs. 0.257+0.01 arbitrary units, respectively), p450 aromatase mRNA was decreased (1.4+0.3 vs. 19.04+1 arbitrary units) and p450scc, p450c17, 3-BHSDII, and COXII showed no changes in PCOS group compared to control group. No differences were found in COXII protein expression of PCOS group compared to control group. In PCOS women, the enhanced expression of the key regulatory steroidogenic enzyme StaR increased steroidogenesis, that concomitantly with the decreased of p450 aromatase expression could result in the accumulation of androgens(A), and lower levels of estrogens(E). In addition the increased 20-HSD mRNA levels could explain the lower progesterone levels associated with PCOS This A/E imbalance avoid the presence of a selectable follicle.