Effects of total saponin of Rhizoma Dioscreae Nipponicae on VEGF, Ang-2 and receptor Tie-2 in synovial tissue of CIA rats / 中国药学杂志

ABSTRACT

OBJECTIVE: To study the effects of total saponin of Rhizoma Dioscreae Nipponicae (TSRDN) on the expression of vascular endothelial growth factor (VEGF), angiopoietin-2 (Ang-2) and receptor Tie-2 in synovial tissue of collagen-induced arthritis (CIA) rats, and to investigate the antiangiogenesis mechanism of TSRDN in treating rheumatoid arthritis. METHODS: After the CIA rat model was successfully established, the rats were randomly divided into 5 groups normal control group, CIA model group, TSRDN group, tripterygium group, and diosgenin group. Real-time PCR was used to detect VEGF mRNA expression in synovial tissue of CIA rats, and immunohistochemical staining was used to observe angiopoietin-2 and receptor Tie-2. RESULTS: VEGF mRNA, Ang-2 and Tie-2 expressions in synovial tissue of CIA rats were obviously higher than normal control group (P < 0.01). After treatment with TSRDN, tripterygium, and diosgenin, the expressions of VEGF mRNA and Ang-2 were obviously lower than those in CIA model group (P < 0.01). But Tie-2 expression showed decreasing trend, and there was no obvious differences between each treatment group. VEGF mRNA expression in TSRDN group was much lower than that in tripterygium group and diosgenin group. CONCLUSION: TSRDN can inhibit angiogenesis in synovial tissue by down regulating expressions of VEGF, Ang-2 and receptor Tie-2.