Effect of Cangfu daotan decoction on ovarian morphology and follicular development in letrozole induced Polycystic Ovary Syndrome model Rats

OBJECTIVE To study the effect of Cangfu daotan decoction(CFDTD) on ovarian morphology and follicular development in letrozole induced polycystic ovary syndrome(PCOS) rats.METHODS SD rats were given letrozole to establish PCOS model, and the estrus cycle was observed by vaginal smear. SD rats were randomly divided into PCOS group, CFDTD 15, 30 g·kg^–1·d^–1groups, and metformin(MH, 50 g·kg^–1·d^–1) group with 10 rats in each group. The same amount of normal saline and corresponding were treated by gavage respectively, and fed with high-fat diet, at the same time, the control group was given the same amount of normal saline and ordinary feed, all rats were treated for 4 weeks. After administration, blood was collected from abdominal aorta and ovarian tissue was collected, and fasting blood glucose(FPG), fasting insulin(FINS), ovarian weight, ovarian diameter, ovarian organ index, serum luteinizing hormone(LH), follicle stimulating hormone(FSH) and testosterone(T) levels were detected. Meanwhile, HE staining and Tunel staining were used to observe the morphology of ovarian tissue and apoptosis. The protein expression of cleaved caspase 3, cleaved caspase 9 and Bcl-2 were detected by Western blotting.RESULTS There was no regular estrus cycle in PCOS rats. Compared with the PCOS group, the left ovarian mass, serum LH and T levels in CFDTD 15 g·kg^–1·d^–1group were significantly decreased(P<0.05), in the CFDTD 30 g·kg^–1·d^–1group and MH group, the levels of FPG, FINS, homeostasis model of assessment of insulin resistance(HOMA-IR), body weight, diameter of left and right ovaries, ovarian organ index, serum LH and T levels were significantly decreased(P<0.05 or P<0.01). The results of HE staining and Tunel staining showed that compared with the PCOS group, the morphology of ovarian tissue was improved and the number of apoptosis positive cells in the treatment group was decreased. The improvement degree was as follows: MH group, CFDTD 30 g·kg^–1·d^–1 group, CFDTD 15 g·kg^–1·d^–1group. Western blotting analysis showed that the expression of cleaved caspase 3 and cleaved caspase 9 protein was down-regulated and Bcl-2 protein expression was up-regulated in the treatment group.CONCLUSION CFDTD can improve the ovarian morphology and follicular development of PCOS rats by inhibiting the apoptosis of granulosa cells, improving insulin resistance and reproductive hormone levels.