银杏叶不同有效成分抑制金属离子诱导人血浆低密度脂蛋白氧化修饰的比较研究

Comparison Study on Inhibitory Effect of Extracts from Leaves of Ginkgo biloba L.on the Oxidation of Human Low Density Lipoproteins

目的 :研究银杏叶总提取物 (EGB76 1)、银杏叶黄酮 (GF)、银杏叶内酯 (GT)对Fe2 +或Cu2 +诱导的人血浆低密度脂蛋白 (LDL)氧化修饰的抑制作用 ,比较三者作用的强弱。方法 :用荧光分光光度法测定LDL自身荧光物质 (LF)、丙二醛 (MDA)及维生素E(VitE)含量 ,计算EGB 76 1、GF、GT对Fe2 +或Cu2 +诱导的LDL氧化修饰的抑制率。结果 :Fe2 +或Cu2 +能引起LDL中VitE含量减少 ,MDA和LF含量升高 ,EGB 76 1、GF、GT对这些改变有抑制作用 ,抑制作用强弱顺序为GF >EGB76 1>GT。结论 :GF在抑制Fe2 +或Cu2

Objective: To compare the effects of extracts from leaves of Ginkgo biloba L (EGB761), ginkgo flavonoids(GF) and ginkgo terpenlactones(GT) on the oxidation of human plasma low density lipoproteins (LDL) induced by Fe 2+ or Cu 2+ Method: LDL was pretreated with EGB761, GF and GT, then was oxidized by CuSO 4 or FeSO 4 6μmol/L for 4h Fluorescencs Spectroscopy methods were adopted to determine the contents of lipofusion(LF), malondialdehyde(MDA) and vitamin E (VitE) of LDL oxidized by Fe 2+ or Cu 2+ and protected by EGB761,GF or GT Result: After the oxidation of LDL induced by Fe 2+ or Cu 2+ , VitE was exhausted, while MDA and LF were markedly increased EGB761, GF and GT prevented the decrease of VitE and increases of MDA and LF in the ox LDL The inhibitory effect was GF>EGB761>GT Conclusion: GF played the main role in anti oxidation