Anti-Angiogenic Activity of Gecko Aqueous Extracts and its Macromolecular Components in CAM and HUVE-12 Cells

Gecko is a kind of traditional Chinese medicine with remarkable antineoplastic activity. However, undefinedmechanisms and ambiguity regarding active ingredients limit new drug development from gecko. This study wasconducted to assess anti-angiogenic properties of the aqueous extracts of fresh gecko (AG) or macromolecularcomponents separated from AG (M-AG). An enzyme-linked immunosorbent assay (ELISA) approach wasapplied to detect the vascular endothelial growth factor (VEGF) secretion of the tumor cells treated with AG orM-AG. The effect of AG or M-AG on vascular endothelial cell proliferation and migratory ability was analyzedby tetrazolium dye colorimetric method, transwell and wound-healing assays. Chick embryo chorioallantoicmembrane (CAM) assays were used to ensure the anti-angiogenic activity of M-AG in vivo. The results showedthat AG or M-AG inhibited the VEGF secretion of tumor cells, the relative inhibition rates of AG and M-AGbeing 27.2% and 53.2% respectively at a concentration of 20 μL/mL. AG and M-AG inhibited the vascularendothelial (VE) cell proliferation with IC50 values of 11.5±0.5 μL/mL and 12.9±0.4 μL/mL respectively. TheVE cell migration potential was inhibited significantly (p<0.01) by the AG (≥24 μL/mL) or M-AG (≥12 μL/mL) treatment. In vivo, neovascularization of CAM treated with M-AG was inhibited significantly (p<0.05)at a concentration of 0.4 μL/mL. This study provided evidence that anti-angiogenesis is one of the anti-tumormechanisms of AG and M-AG, with the latter as a promising active component.