The role of MiR-324-3p in polycystic ovary syndrome (PCOS) via targeting WNT2B.

OBJECTIVE: To investigate the expression of microRNA-324-3p (miR-324-3p) in polycystic ovary syndrome (PCOS) and its effects on the proliferation and apoptosis of ovarian granulosa cells.

MATERIALS AND METHODS: A total of 60 Sprague-Dawley (SD) rats were randomly divided into normal group (n=30) and experimental group (n=30). Rats in the experimental group were intramuscularly injected with dehydroepiandrosterone (DHEA) (6 mg/100 g of body weight) and 0.2 mL oil for injection, while those in normal group were intramuscularly injected with 0.2 mL oil for injection. The ovarian tissues of PCOS model rats were removed to extract the total ribose nucleic acid (RNA). The expression of miR-324-3p was detected via reverse transcription-polymerase chain reaction (RT-PCR). Primary ovarian granulosa cells were isolated and cultured, and NC-miRNA and miR-324-3p mimic were transfected into cells. After 48 h, cell proliferation and apoptosis were detected via cell counting kit 8 (CCK-8) and flow cytometry assay, respectively. The targeted molecule of miR-324-3p was explored using bioinformatics, and dual-luciferase assay was performed to verify the effect of miR-324-3p on WNT2B expression. Granulosa cells were co-transfected with WNT2B-small-interfering RNA (siRNA) and miR-324-3p mimic, and then cell proliferation and apoptosis were detected via CCK-8 and flow cytometry assay, respectively.

RESULTS: The expression of miR-324-3p in ovarian tissues of PCOS group was significantly lower than that of normal group (p < 0.01). After transfection with miR-324-3p mimic into granulosa cells, cell proliferation was significantly inhibited and cell apoptosis was promoted (p < 0.01). MiR-324-3p exerted its effect on granulosa cells by directly targeting WNT2B. Silencing WNT2B expression could reverse the effects of miR-324-3p on proliferation and apoptosis of granulosa cells (p < 0.05).

CONCLUSIONS: The expression of miR-324-3p in the ovary of PCOS rats is decreased significantly. Overexpression of miR-324-3p can reduce the proliferation and induce the apoptosis of granulosa cells via targeting of WNT2B.