离体SH-SY5Y细胞内酸化对早老素-1表达的影响

Effect of the intracellular acidification on presenilin-1 expression in SH-SY5Y cells

目的研究早老素-1(PS1)在细胞内pH值降低时的表达情况,探讨细胞内pH值变化对γ-分泌酶活性的影响。方法本研究抑制细胞表面酸碱调节基因Na+-H+交换泵第一亚型(NHE1)的表达和酸化培养基,使细胞内pH值降低,构建细胞内酸化的SH-SY5Y细胞模型,将实验对象分为正常组、阴性对照组、NHE1组和酸化培养基组,应用ELISA法及western blot-ting,检测各组PS1的蛋白浓度及表达,分析细胞内pH值变化对PS1表达和活性的影响及其与γ-分泌酶的关系。结果检测胞膜离子交换蛋白NHE1组和酸化培养基组细胞内的PS1活性和蛋白表达较正常对照组和阴性对照组有显著增高(P<0.05),而NHE1组和酸化培养基组组间比较无明显差异,正常对照组和阴性对照组组间比较也无明显差异。结论细胞内pH值降低可促使PS1表达量增加,活性增高,提示细胞内pH值降低可能促使γ-分泌酶活性增高。

Objective To investigate the expression of PS1 when the pH descended in cells,and to explore the impact of variations of pH in cells on γ-secretases.Methods The model that acidulated in cells was constructed,and the expression and activity of PS1 was detected.The impact of variations of pH in cells on the expression and activity of PS1 was analyzed,and the relation of variations of pH in cells with γ-secretases was explored.Results Compared to normal control group and negative control group,the expression and activity of PS1 of Na＋-H＋ exchanger1 gene-knock-on low group and acidulated substrate group were significantly increased（P〈0.05）.There was no obvious difference between Na＋-H＋ exchanger1 gene-knock-on low group and acidulated substrate group.There was no significant difference between red to normal control group and negative control group.Conclusion The decrease of pH in cells can lead to the rise of expression and activity of PS1.So we can come to a conclusion that the decrease of pH in cells can result in the rise of activity of γ-secretases.