铝对PC12细胞淀粉样前体蛋白β位点裂解酶-1蛋白及基因表达的影响

[目的]探讨铝对PC12细胞淀粉样前体蛋白（APP）β位点裂解酶-1（beta-site amyloid precursor proteincleaving enzyme-1,BACE1）蛋白及基因表达的影响。[方法]采用PC12细胞进行培养及麦芽酚铝[Al（mal）3]染毒,将细胞分为6组,分别为：200μmol/L生理盐水组;0、50、100、200和400μmol/L Al（mal）3组。分别采用酶联免疫吸附测定法（enzyme linked immunosorbent assay,ELISA）、荧光实时定量聚合酶链反应（quantitative real-time polymerase chainreaction,qRT-PCR）于染毒12、24和48 h后测定BACE1蛋白含量及基因表达。[结果]细胞计数试剂盒-8（CCK-8）细胞活力测定结果显示,不同浓度Al（mal）3染毒PC12细胞,可使其细胞活力呈现随染毒时间延长而逐渐下降的趋势。qRT-PCR结果显示,100μmol/L Al（mal）3组在染毒48 h后BACE1基因表达明显高于生理盐水组、0μmol/L Al（mal）3组,差异有统计学意义（P〈0.05）;200、400μmol/L Al（mal）3组染毒12、24、48 h后BACE1基因表达明显高于生理盐水组和0μmol/L Al（mal）3组,差异均有统计学意义（P〈0.05）。ELISA测定结果显示,染毒12 h后400μmol/L Al（mal）3组BACE1表达量明显高于生理盐水组和0μmol/L Al（mal）3组,差异均有统计学意义（P〈0.05）;染毒24 h后200、400μmol/L Al（mal）3组BACE1表达量明显高于生理盐水组和0μmol/L Al（mal）3组,差异有统计学意义（P〈0.05）;染毒48h后400μmol/L Al（mal）3组的BACE1表达量明显高于生理盐水组和0μmol/L Al（mal）3组,差异有统计学意义（P〈0.05）。[结论]Al（mal）3对PC12细胞具有明显毒性作用,该作用可能与麦芽酚铝致PC12细胞BACE1蛋白和基因表达增强有关。

Effects of Aluminum on the Expression of BACE1 Proteins and Genes in PC12 Cells

[Objective] To explore the effect of aluminum on the expression of beta-site amyloid precursor protein cleaving enzyme-1（BACE1） proteins and genes in PC12 cells.[Methods] Cultured PC12 cells were randomly divided into 6 groups：200 μmol/L saline group,and 0,50,100,200 and 400 μmol/L Al（mal）3 groups.The protein and gene expression of BACE1 was detected by enzyme linked immunosorbent assay（ELISA） and quantitative real-time polymerase chain reaction（qRT-PCR） at 12,24 and 48 h after treatment.[Results] The viability of PC12 cells was decreased in a time-dependent manner in different dose groups.qRT-PCR results showed that the expression of BACE1 mRNA in 100 μmol/L Al（mal）3 group increased significantly compared with that in 0 μmol/L Al（mal）3 group and saline group after 48 h exposure（P 0.05）;and that in 200 and 400 μmol/L Al（mal）3 groups increased significantly compared with that in 0 μmol/L Al（mal）3 group and saline group after 12,24 and 48 h exposure（P 0.05）.ELISA detection results showed that,compared with the 0 μmol/L Al（mal）3 group and the saline group,the expression of BACE1 in 200 μmol/L Al（mal）3 group increased significantly after 24 h exposure（P 0.05）;and that in 200 and 400 μmol/L Al（mal）3 groups increased significantly after 12,24 and 48 h exposure（P 0.05）.[Conclusion] The obvious toxicity of Al（mal）3 on PC12 cells may be related to the enhancing expression of BACE1 protein and gene in PC12 cells.