P-228: Altered Expression of Folliclestimulating Hormone Receptor and Luteinizing Hormone Receptor in Granulosa Cells from Women with Polycystic Ovary Syndrome

Background: Polycystic ovary syndrome (PCOS) is a common complex genetic endocrinopathy, affecting 5 - 10% of women at reproductive age. PCO granulosa cells seem to have abnormal responses to follicle- stimulating hormone (FSH). FSH is considered to be a pituitary glycoprotein that plays an important role during folliculogenesis as it promotes the proliferation and differentiation of granulosa cells and the maturation and development of follicles. The effect of FSH is believed to be mediated by the binding of the hormone with a specific receptor, FSHR, which is situated on the granulosa cells. Through the cascade effect, FSHR transfers the biological signals of FSH to the downstream network. Accordingly, activation of the LH receptor (LHR) in ovarian granulosa and theca cells initiates signaling cascades regulating transcription of genes which is necessary for ovulation and luteinization. LHR expression requires appropriate hormonal stimulation by FSH and estradiol. Objective: The aim of this prospective study was to analyze the expression of these genes at the human granulosa cells of women with PCOS. Materials and Methods: After the approval of Iran University of medical sciences ethics committee and written informed consent of the patient, follicular fluid was collected from patients undergoing oocyte retrieval. 80 patients were divided into two groups, PCOS and control according to Rotterdam criteria. A series of isolation and purification methods was performed, including density gradient centrifugation, MACS (use of antibody bead complexes) and RNA extraction. Reverse transcriptase PCR (RT-PCR) was performed and quantification of gene expression levels was achieved by real-time quantitative PCR. Results: The expression of FSH receptor was significantly different between case and control groups, with the lower expression in the PCOS group (p<0.001). Considering all the women with and without PCOS undergoing controlled ovarian hyper stimulation, significant relationship was observed between the body mass index and FSHR level (p<0.05). There was a significant difference in LHR expression levels in PCOS women compared to control women (p<0.02). In both PCOS patients and controls, a strong positive linear correlation was observed between the FSH and LH receptor mRNA levels (r=0.92, p<0.05).Conclusion: Findings from the previous studies show that the elevated expression of FSHR mRNA can be regarded as one of the earliest markers for differentiating granulosa cells. Also, the expression of LHR mRNA has been proposed to be associated with follicle selection. Since the selection of follicle and its further maturation to a dominant follicle does not occur in PCOS patients, it seems that PCO granulosa cells may have abnormal responses to FSH and LH. The results of our study are consistent with these findings.