麦芽酚铝对大鼠肾上腺嗜铬细胞瘤细胞β-淀粉样蛋白42蛋白表达的影响及其作用机制

Effect of aluminum-maltolate on the expression of Aβ42 proteins in PC12 of rats cells and its mechanism

目的探讨铝对大鼠肾上腺嗜铬细胞瘤(PC12)细胞β-淀粉样蛋白(Aβ)42表达的影响及其作用机制。方法将处于对数生长期的PC12细胞分别暴露于含麦芽酚铝终浓度为0(对照)、50、100、200和400μmol/L的完全培养基染毒12、24、48 h。采用CCK-8法测定细胞活性,采用酶联免疫吸附(ELISA)测定法测定PS1、Aβ42蛋白的含量。结果与对照组比较,200、400μmol/L麦芽酚铝染毒12 h时及各浓度麦芽酚铝染毒24 h、48 h时PC12细胞的存活率均较低,差异有统计学意义(P<0.05);且随着麦芽酚铝染毒浓度的升高,不同染毒时间PC12细胞的存活率均呈逐渐降低的趋势。与对照组比较,400μmol/L麦芽酚铝染毒12 h时及200、400μmol/L麦芽酚铝染毒24 h、48 h时PC12细胞PS1蛋白的含量均增加,差异有统计学意义(P<0.05)。与对照组比较,400μmol/L麦芽酚铝染毒12 h时及200、400μmol/L麦芽酚铝染毒24 h时以及100、200、400μmol/L麦芽酚铝染毒48 h时PC12细胞Aβ42蛋白的含量均增加,差异有统计学意义(P<0.05)。结论γ-分泌酶表达增加可能是铝致PC12细胞Aβ42蛋白含量增多的重要原因之一。

Objective To explore the effect of aluminum on the expression of β-amyloid protein （Aβ） 42 in rats＇ pheochromocytoma cells（PC12 cells） and its mechanism. Methods The PC12 cells in logarithmic growth phase were incubated in culture media with aluminum-maltolate[Al（mal）3] at final concentration of 0,50,100,200, and 400μmol/L for 12 h, 24 h and 48 h,respectively. The cell counting kit-8 was used to detect cell viability of PC12 cells,and the protein expressions of presenilin I（PS1） and Aβ42 was detected by enzyme-linked immunosorbent assay（ELISA）. Results The cell vitality of PC12 cells incubated by 200,400 μmol/L Al（mal）3 for 12 h,or incubated by 50,100,200,and 400 μmol/L Al（mal）3 for 24 h,48 h were significantly decreased compared with the control group （P〈0.05）,with statistical significance. The protein expression of PS1 in PC12 ceils treated with 400 μmol/L Al（mal）3 for 12 h or treated with 200,400 μmol/L Al（mal）3 for 24 h,48 h were increased significantly compared with those of control groups （P〈0.05） , with statistical significance. The protein expression of Aβ42 in these PC12 ceils treated with 400 μmol/L Al（mal）3 for 12 h,200,400 μmol/L Al（mal）3 for 24 h,or 100,200,and 400 μmol/L Al（mal）3 for 48 h,were increased significantly compared with those of control group（P〈0.05）, with statistical significance. Conclusion The increased expression of γ-seeretase may be one of the reasons for the increased protein expression of Aβ42 in PC12 cells induced by aluminum.