Inhibitory effects of controlled ovarian stimulation on the expression of GDF9 and BMP15 in oocytes from women with PCOS

Abstract

To explore the effects of controlled ovarian stimulation (COS) on the expression of growth differentiation factor 9 (GDF9) and bone morphogenetic protein 15 (BMP15) in oocytes and granulosa cells from patients with or without polycystic ovary syndrome (PCOS). This case-control study was conducted in the university affiliated hospital. The study comprised four groups of patients: eighteen PCOS patients with COS (stimulated-PCOS) and twenty-two PCOS patients without COS (unstimulated-PCOS), twenty-nine normal ovulatory women with COS (stimulated-control) and twenty-eight normal ovulatory women without COS (unstimulated-control). The oocytes and granulosa cells were collected and the abundance of GDF9 and BMP15 mRNA in the cells were detected by nested quantitative real-time PCR. The abundance of GDF9 and BMP15 mRNA was significantly higher both in oocytes (P < 0.01, P < 0.001, respectively) and GCs (P < 0.01, P < 0.05, respectively) from stimulated-control group than in unstimulated-control group. However, there was no significant difference for GDF9 or BMP15 mRNA in oocytes from stimulated-PCOS goup compared with unstimulated-PCOS group (P > 0.05, P > 0.05, respectively). The abundance of GDF9 mRNA was significantly lower (P < 0.01) while the abundance of BMP15 mRNA was significantly higher (P < 0.001) in GCs from stimulated-PCOS group than in unstimulated-PCOS group. The controlled ovarian stimulation can promote the expression of GDF9 and BMP15 both in oocytes and GCs from normal ovulatory women. However, the stimulating effects may be inhibited in oocytes from PCOS patients, which subsequently impair cytoplasm maturation and lead to poor oocyte quality.