【摘要】 目的比较丹酚酸B(Sal B)和银杏叶提取物EGb 761对β-淀粉样蛋白(β-AP)纤维形成及细胞毒作用的影响。方法运用硫黄素T(ThT)荧光法和电子显微镜技术分析Sal B和EGb 761对β-AP1-40聚集和纤维形成的影响;另将β-AP25-35预先老化7 d,用MTT法和流式细胞仪检测两种提取物对此老化蛋白造成的PC12细胞毒性的保护作用,用荧光法观察β-AP25-35作用后细胞内活性氧含量的变化以及两种提取物的作用。结果Sal B和EGb 761都可有效地抑制β-AP1-40纤维的形成,明显抑制老化的β-AP25-35对PC12细胞的毒性作用,降低β-AP25-35造成的细胞内活性氧含量的增加。Sal B的有效剂量远远低于EGb 761。结论Sal B对β-AP神经毒性的抑制作用强于EGb 761。更多还原

【Abstract】 Aim To compare the effects of salvianolic acid B（Sal B） and Ginkgo biloba extract EGb 761 on β-amyloid peptide（β-AP） fibril formation and cytotoxicity to PC12 cells.Methods The inhibitory effects of Sal B and EGb 761 on βAP₁-40 fibril formation were determined by using fluorescence analysis with Thioflavin T（ThT） and electron microscopic image.β-AP₂5-35 was aged by incubating at 37 ℃ for 7 d,then the protein was incubated with PC12 cells.The protective effects of Sal B and EGb 761 against cytotoxicity induced by aged β-AP₂5-35 in PC12 cells were evaluated by MTT reduction assay and flow cytometric analysis.β-AP₂5-35-induced accumulation of intracellular reactive oxygen species（ROS） was determined by fluorescence analysis.Results Both Sal B and EGb 761 inhibited the formation of amyloid fibrils,protected PC12 cells from β-AP₂5-35-induced cytotoxicity,and decreased ROS accumulation caused by β-AP₂5-35.The effective doses of Sal B were far lower than those of EGb 761.Conclusion Sal B was much more efficient than EGb 761 in inhibiting β-AP aggregation and in protecting PC12 cells from β-AP-induced cytotoxicity.更多还原