Anti-angiogenic activity of julibroside J8, a natural product isolated from Albizia julibrissin.

Purpose: The purpose of this study was to investigate the anti-angiogenic properties of julibroside J(8), a triterpenoid saponin isolated from Albizia julibrissin.

Methods: In the presence of juliborside J(8,) the growth of human microvascular endothelial cells (HMEC-1), four human tumor cell lines, and a normal cell line (MRC-5) was evaluated by MTT assay. The in vivo anti-angiogenic effect of julibroside J(8) was evaluated on a chorioallantoic membrane (CAM) and in transplanted colon carcinoma cells in a nude mice neovascularisation model.

Results: Treatment with 0.5-4 microg/ml julibroside J(8) resulted in dose-dependent inhibition of growth, migration, and tube formation in HMEC-1 cells; julibroside J(8) also inhibited the formation of microvessels on CAM at a concentration of 10-50 microg/egg and reduced vessel density within tumor at a concentration of 0.5-3mg/kg.

Conclusions: Julibroside J(8) may be a potent anti-angiogenetic and cytotoxic drug; further investigation is warranted.