Inhibitory Effects of Rehmannia glutinosa Liboschitzon Endothelial Cell Proliferation

Abstract

Vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) are the most importantangiogenic molecules associated with tumor-induced neovascularization. This study was caried out to investigate inhibitoryRehmannia glutinosa LIBOSCHITZ (Rehmannia Radix and Rehmannia Radix Preparata) onendothelial cell proliferation. The methanol extracts from the medicinal herb were fractionated into n-hexane, ethyl acetate, n-butanol and aqueous fractions. Among the four fractions, the n-butanol fraction from R. Radix on exhibited highly effectiveinhibition (79% inhibition) on the binding of KDR/Flk-1-Fc to immobilized VEGF165 R.Radix (45% inhibition) at the concentration of 100. /. . The n-butanol fraction eficiently blocked the VEGF- and bFGF-induced HUVEC proliferation in a dose-dependent maner, but did not afect the growth of HT1080 human fibrosarcomacels. The n-butanol fraction more efficiently blocked the binding of KDR/Flk-1-Fc to imobilized VEGF165 and VEGF- andbFGF-induced human umbilical vein endothelial R. Radix Preparata. Our results sug-gest that Rehmania Radix may be used as a candidate for developing anti-angiogenic agent.