Effect of Bushen yixue decoction on follicular development in experimental androgen-sterilized anovulatory rats and its possible mechanism of action

Purpose : To explore the activities of Bushen yixue decoction (BSY) against follicular development in anovulatory rats. Methods : Rats were divided into normal, normal control, clomifene citrate (positive control, orally, 5 mg/kg), and BSY (orally, 50, 100, 200 mg/kg) groups. Anovulatory rats were prepared by testosterone propionate injection (1.5 mg/rat). After 70 days, daily vaginal smears were performed for 10 days until no obvious sexual cycle was observed, indicating that androgen-sterilized anovulatory rats were successfully established. High performance liquid chromatography (HPLC) was used to analyse BSY chemical composition. Levels of follicular stimulating hormone (FSH), luteinizing hormone (LH), oestradiol (E2), progesterone (P), prolactin (PRL), inhibin (INH), activin (ACT) and follistatin (FS) were determined by radioimmunoassay or enzyme linked immunosorbent assay (ELISA). Western blotting was used to determine Bcl-2, cleaved-caspase-3, Bax, MMP-9 and VEGF in ovarian tissues. Results : BSY increased (p < 0.05) the levels of FSH, LH, E2 (p < 0.05) and ACT, but decreased (p < 0.05) the levels of PRL, INH and FS, relative to control rats. Expressions of VEGF (p < 0.01), MMP-9 (p < 0.05) and Bcl-2 (p < 0.01) were up-regulated by BSY, whereas Bax (p < 0.01) and C-caspase-3 (p < 0.01) were down-regulated. Conclusion : BSY promotes follicular development of anovulatory rats via regulating INH-ACT-FS hormones, VEGF, MMP-9, Caspase-3, Bax, and Bcl-2. Thus, BSY may have the potential to be developed for clinical management of infertility. Keywords : Bushen yixue decoction, Follicular development, Inhibin-Activin-Follistatin (INH-ACT-FS) system, Androgen-sterilized anovulatory rats