八氢贯叶金丝桃素乙酸酯对淀粉样前体蛋白水解途径的影响及机制

Effect of(8H)-Ac-HF on the processing of amyloid precursor protein

目的探讨合成的稳定化合物八氢贯叶金丝桃素乙酸酯[(8H)-Ac-HF]对皮层原代神经元细胞中淀粉样前体蛋白(APP)水解途径的影响及其作用机制。方法建立SD大鼠皮层原代神经元细胞体外培养体系,用MTT法检测(8H)-Ac-HF对原代神经元细胞的生长活力影响;用ELISA方法检测(8H)-Ac-HF对原代神经元细胞培养上清液中可溶性淀粉酶前体蛋白α(sAPPα)分泌及α-分泌酶活性的影响;用Western blot检测(8H)-Ac-HF对解聚金属蛋白酶10(adisintegrin and metalloprotease,ADAM10)蛋白表达的影响;并通过蛋白激酶C(PKC)抑制剂calphostinC(Cal.C)观察其可能作用的信号途径。结果 0～50μmol/L(8H)-Ac-HF处理皮层神经元30 h对细胞生长活性无显著影响;20、50μmol/L(8H)-Ac-HF可增加神经元细胞sAPPα的胞外分泌(P<0.01),增加α-分泌酶活性,上调ADAM10蛋白的表达;其对sAPPα、ADAM10和α-分泌酶的上调作用可受PKC抑制剂Cal.C抑制。结论 (8H)-Ac-HF可通过PKC信号途径,增加ADAM10表达及α-分泌酶活性,促进APP经非淀粉样途径水解。

Objective To study the effect and mechanism of the stable compound of octahydrohyperforin acetate（（8H）-Ac-HF） on the processing of amyliod precursor protein（APP） in primary cortical neurons.Methods The primary rat cortical neurons were cultured and the activities of neurons were detected by MTT.The secretion of extracellular soluble amyloid precursor protein α（sAPPa） in cultured medium and α-secretase activity were detected by ELSIA.The expression of adisintegrin and metalloprotease 10（ADAMl0） was detected by Western blot.Results The dosages of 0-50 μmol/L（8H）-Ac-HF had no influence on the viability of cortical neurons after 30 h treatment.The dosages of both 20 and 50 μmol/L（8H）-Ac-HF increased the extracellular secretion of sAPPa in cultured medium,improved the activity of α-secretase,and upgraded the expression of ADAM10 which could be inhibited by the pan PKC inhibitor,Cal.C.Conclusion（8H）-Ac-HF can improve α-secretase-mediated APP processing via a PKC signaling pathway.