淫羊藿黄酮对APP695基因转染神经细胞β-淀粉样肽及β-分泌酶的影响

Effects of Epimedium Flavanoids on β-amyloid in APP695 cDNA-transfected Nerve Cells and on β-secretase Activity in Vitro

目的观察淫羊藿黄酮(EF)对APP695基因转染SH-SY5Y细胞中β-淀粉样肽(Aβ)水平的影响。方法利用免疫沉淀+Western印迹法、放射免疫法分别检测细胞培养上清液和细胞裂解液中的Aβ水平。通过测定β-分泌酶(BACE1)切割荧光底物所得的荧光值检测BACE1活性。结果EF2.5～25g/ml与APP695基因转染SH-SY5Y细胞模型共孵育24h能明显降低模型细胞培养液中的Aβ含量(P<0.05,P<0.01)。体外试验中EF50g/ml对BACE1活性的抑制率为95.0%。结论EF能降低APP695基因转染细胞生成和分泌Aβ。

Objective To investigate the effects of Epimedium flavanoids （EF） on β-amyloid （Aβ） in APP695 cDNA-transfected human neuroblastoma cell line SH-SYSY cells. Methods The immunoprecipitation plus Western blotting and radioimmunoassay were used to detect Aβ concentration in the supernatant of cell culture and cell disruption fluid. The activity of β-secretase （BACE1） was measured by detecting the fluorescence value of substrate cut by BACE1. Results Incubation of EF 2.5-25 g/ml with APP695 cDNA transfected SH SYSY cells for 24 h significantly decreased Aβ content in the supernatant of cell culture （ P d0.05, P d0.01）. EF 50 g/ml inhibited the activity of BACE1 by 95.0% in vitro. Conclusion EF can decrease Aβ production and secretion of APP695 cDNA-transfected nerve cells.