Alternagin-C, a Disintegrin-like Protein, Induces Vascular Endothelial Cell Growth Factor (VEGF) Expression and Endothelial Cell Proliferationin Vitro

Márcia R. Cominetti, Cristina H. B. Terruggi, Oscar H. P. Ramos, Jay W. Fox, Andrea Mariano-Oliveira, Marta S. De Freitas, Camila C. Figueiredo, Veronica Morandi, Heloisa S. Selistre-de-Araujo
2004 Journal of Biological Chemistry  
Alternagin-C (ALT-C), a disintegrin-like protein purified from the venom of the Brazilian snake Bothrops alternatus, interacts with the major collagen I receptor, the ␣ 2 ␤ 1 integrin, inhibiting collagen binding. Here we show that ALT-C also inhibits the adhesion of a mouse fibroblast cell line (NIH-3T3) to collagen I (IC 50 2.2 M). In addition, when immobilized on plate wells, ALT-C supports the adhesion of this cell line as well as of human vein endothelial cell (HUVEC). ALT-C (3 M) does not
more » ... LT-C (3 M) does not detach cells that were previously bound to collagen I. ALT-C (5 nM) induces HUVEC proliferation in vitro, and it inhibits the positive effect of vascular endothelial growth factor (VEGF) or FGF-2 on the proliferation of these cells, thus suggesting a common mechanism for these proteins. Gene expression analysis of human fibroblasts growing on ALT-C-or collagen-coated plates showed that ALT-C and collagen I induce a very similar pattern of gene expression. When compared with cells growing on plastic only, ALT-C up-regulates the expression of 45 genes including the VEGF gene and downregulates the expression of 30 genes. Fibroblast VEGF expression was confirmed by RT-PCR and ELISA assay. Up-regulation of the VEGF gene and other growth factors could explain the positive effect on HUVEC proliferation. ALT-C also strongly activates Akt/PKB phosphorylation, a signaling event involved in endothelial survival and angiogenesis. In conclusion, ALT-C acts as a survival factor, promoting adhesion and endothelial cell proliferation.
doi:10.1074/jbc.m311771200 pmid:14766757 fatcat:ncu72jfvrveghe3kkeatzpzd3i