Anti-angiogenic effects of total flavonoids from Scutellaria barbata D. Don

Background: Angiogenesis is closely related to the growth, invasion and metastasis of the tumor, also anticancer therapy key targets. Scutellaria barbata D. Don (S. barbata), a traditional Chinese medicine, is being used for treatment of many diseases including cancer. However, the antitumor molecular mechanism of S. barbata was unclear. This study is aimed to investigate the inhibitory effect of total flavones from S. barbata (TF-SB) on angiogenesis. Methods: Human umbilical vein endothelial cells (HUVECs) were treated with various concentrations of TF-SB. Cell viability was examined by 3-(4,5) –dimethylthiahiazo (-z-y1)-3,5diphenytetrazoliumromide (MTT) assay. the activity of TF-SB on migration of HUVECs by the scratch assay. The ability of HUVECs forming network structures in vitro was tested by tube formation assay. Chick embryo chorioallantoic membrane (CAM) assay was performed to detect the in vivo anti-angiogenic effect. The expression of VEGF was measured by ELISA assay. Results: Our results showed that TF-SB inhibited the proliferation and migration of HUVECs in a dose dependent manner. At the same time, TF-SB could significantly suppress the process of in vitro angiogenesis of HUVECs on matrigel, and the angiogenesis of CAM in vivo. Furthermore, TF-SB treatment down-regulated the expression of VEGF in both HUVECs and MHCC97-H human hepatocarcinoma cells. Conclusion: TF-SB could significantly suppress the process of in vitro angiogenesis of HUVECs on matrigel, and the angiogenesis of CAM in vivo. These data suggest that TF-SB may serve as a potent anti-angiogenic agent.