Anti-angiogenesis effect and mechanism study of Huangzhi Neiyi capsule in a rat endometriosis model

Objective: To investigate the effects and possible mechanism of Huangzhi Neiyi capsule (HZNY) on angiogenesis in rats with endometriosis. Methods: Sixty Sprague-Dawley rats were used to establish an endometriosis model by autologous transplantation and were randomly divided into sham operation, model, gestrinone (0.25 g/kg), and HZNY (4.5 and 9 g/kg) groups. All drugs were administered orally for 28 days. At the end of the experiment, all rats were killed by cervical dislocation, and the expression of proliferating cell nuclear antigen (PCNA) and CD31 in ectopic endometrial tissue was assessed by immunohistochemistry. The level of vascular endothelial growth factor (VEGF) in peritoneal fluid was determined by enzyme-linked immunosorbent assay. The mRNA expression of VEGF and hypoxia inducible factor-1 alpha (HIF1A) in ectopic endometrium was evaluated by reverse transcription-PCR. Results: HZNY suppressed the expression of PCNA and CD31 in ectopic endometrium, reduced concentrations of VEGF in peritoneal fluid, and reduced mRNA expression of VEGF and HIF1A in ectopic endometrium. Conclusions: HZNY suppressed angiogenesis in endometriosis rats, perhaps by inhibiting expression of VEGF and HIF1A.