目的探索银杏叶提取物（EGb 761）对胰岛素淀粉样纤维化及纤维细胞毒性的抑制作用。方法在pH 2．0、57℃孵育胰岛素，采用硫黄素荧光检测牛胰岛素形成淀粉样纤维的动力学曲线，透射电镜观察纤维形态；以淀粉样纤维诱导人红细胞的聚集和溶血为指标，评估EGb 761对胰岛素纤维细胞毒性的抑制作用。结果胰岛素在酸性溶液及57℃的条件下孵育可形成淀粉样纤维，EGb 761能够抑制淀粉样纤维的形成，使纤维形态改变，并能够抑制淀粉样纤维诱导的红细胞聚集和溶血。结论 EGb 761能够抑制胰岛素的淀粉样纤维化，并使胰岛素纤维的细胞毒性降低。%Objective To investigate the inhibitory effect of Ginkgo biloba leave extract (EGb 761) on amyloid fibrillation and fibril-lar cytotoxicity of insulin .Methods Insulin fibrils were prepared by incubating the protein at pH 2 .0 and 57 ℃ .Fibril formation was monitored by thioflavine T fluorescence ,and the fibrillar morphology was visualized under transmission electron microscopy . The cytotoxicity of insulin fibril was evaluated by measuring hemolysis and aggregation of human red blood cell treated with the fibrils .Results Incubation of insulin under acidic medium at 57 ℃ resulted in the formation of amyloid fibril .The growth kinetics and morphology of the fibril were changed by co-incubating insulin and EGb 761 .Insulin fibrils induced aggregation and hemolysis of human red blood cell .EGb 761 attenuated the fibril-induced cytotoxicity .Conclusion EGb 761 is able to inhibit the amyloid formation of insulin and to decrease the fibril-induced cytotoxicity .
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