Objective: To explore the mechanism of polypeptide extract from scorpion venom (PESV) on inhibiting angiogenesis.
Methods: The H22 hepatoma tumor model was established by subcutaneously implanting H22 hepatoma cells into mice. The tumor-bearing mice were randomly divided into 4 groups, i.e., the control group, the high dose PESV group, the low dose PESV group, and the 5-fluorouracil (5-Fu) group, 10 mice in each group. The intervention was lasted for 14 days. The growth curve of the tumor volume was drawn and the inhibition rate calculated. Pathological changes of the tumors were observed by HE staining. The microvessel density (MVD) was detected using SP method. The protein expression levels of phosphatidylinositol 3-kinase (P13K), phosphoprotein kinase B (P-Akt), hypoxia-inducible factor-1 alpha (HIF-1 )alpha, and vascular endothelial growth factor-A (VEGF-A) were detected by immunohistochemical assay and Western blot.
Results: The tumor inhibitory rate was 64.8%, 43.7%, and 32.4% in the 5-Fu group, the high dose PESV group, and the low dose PESV group. Compared with the control group, the protein expression of PI3K, P-Akt, HIF-1alpha, and VEGF-A were obviously inhibited by PESV and 5-Fu (P <0. 05,P <0. 01). The MVD also decreased in the high and low dose PESV groups (P < 0.05).
Conclusions: PESV could inhibit the angiogenesis of H22 hepatoma. The mechanisms might be associated with suppressing the expression of PI3K, P-Akt, HIF-1 alpha, and VEGF-A.