Anti-angiogenic effects of ethanolic extract of Artemisia sieberi compared to its active substance, artemisinin

ABSTRACT

Abstract Angiogenesis plays a key role in tumor growth, invasion and metastasis of cancer diseases and therefore, the inhibition of angiogenesis can provide an important therapeutic approach in cancer diseases. This study was designed to compare the anti-angiogenic activities of the ethanolic extract of Artemisia sieberi Besser, Asteraceae, and its active substance, artemisinin in both in vitro and in vivo models. To compare cytotoxicity level of ethanolic extract of A. sieberi with artemisinin, different concentrations (1–100 µg/ml) were tested using MTT assay on human umbilical vein endothelial cells. The anti-angiogenic properties of serial concentrations of ethanolic extract of A. sieberi and artemisinin were examined on human umbilical vein endothelial cells using a three-dimensional angiogenesis assay (in vitro model) and in the chick chorioallantoic membrane assay as in vivo model. The effects of ethanolic extract of A. sieberi and artemisinin were also tested on the expression of VEGFR-1, VEGFR-2 and CD34 genes using real-time PCR. Ethanolic extract of A. sieberi and artemisinin significantly (p < 0.001) inhibited the angiogenesis in the human umbilical vein endothelial cells culture whilst the ethanolic extract of A. sieberi showed higher effect in a concentration-dependent fashion (p < 0.001). The chick chorioallantoic membrane angiogenesis was also completely inhibited by ethanolic extract of A. sieberi at concentration of 33 ng/100 µl/egg. The gene expression analysis showed that the ethanolic extract of A. sieberi and artemisinin reduced the transcription of VEGFR-1, VEGFR-2 and CD34 genes in a concentration-dependent manner. This study demonstrated that the ethanolic extract of A. sieberi is strongly able to inhibit the angiogenesis in human umbilical vein endothelial cells and chick chorioallantoic membrane models compared to the artemisinin.