Anti-angiogenic effect of triterpenoidal saponins from Polygala senega.

Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamada-oka, Suita, Osaka 565-0871, Japan.
Journal of Natural Medicines (Impact Factor: 1.52). 11/2010; 65(1):149-56. DOI: 10.1007/s11418-010-0477-7
Source: PubMed

ABSTRACT Senegasaponins [senegin II (1), senegin III (2), senegin IV (3), senegasaponin a (4), and senegasaponin b (5)] from Polygala senega were re-discovered as selective anti-proliferative substances against human umbilical vein endothelial cells (HUVECs). Senegasaponins (1-5) showed anti-proliferative activity against HUVECs with IC(50) values in the range 0.6-6.2 μM, and the selective index was 7-100-fold in comparison with those for several cancer cell lines, while the desacyl mixture of senegasaponins (6) and tenuifolin (7) lost anti-proliferative activity, indicating that the 28-O-glycoside moiety and methoxycinnamoyl group were essential for the HUVEC-selective growth inhibition of senegasaponins. Senegin III (2) inhibited the vascular endothelial growth factor (VEGF)-induced in vitro tubular formation of HUVECs and basic fibroblast growth factor (bFGF)-induced in vivo neovascularization in the mouse Matrigel plug assay. Moreover, senegin III (2) suppressed tumor growth in the ddY mice s.c.-inoculated murine sarcoma S180 cells. The analysis of the action mechanism of senegin III (2) suggested that the induction of pigment epithelium-derived factor (PEDF) would contribute to the anti-angiogenic effects of senegasaponins.

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