基于PI3K/Akt/GSK3β信号通路的芥子酸抗Aβ1-42致PC12细胞损伤的机制研究

Study on the Mechanism of Sinapic Acid against PC12 Cell Injury Induced by Aβ1-42 Based on PI3K/Akt/GSK3βSignaling Pathway

目的:基于磷脂酰肌醇-3-激酶(PI3K)/蛋白激酶B(Akt)/糖原合成激酶3β(GSK3β)信号通路探讨芥子酸(SA)抗β淀粉样蛋白1-42(Aβ1-42)致PC12细胞损伤的作用机制。方法:将大鼠PC12细胞随机分为对照组、Aβ组(Aβ1-422μmol/L)、Aβ+SA组(Aβ1-422μmol/L+SA 100μmol/L)、Aβ+SA+LY组[Aβ1-422μmol/L+SA 100μmol/L+LY294002(PI3K抑制剂)10μmol/L]、Aβ+LY组(Aβ1-422μmol/L+LY29400210μmol/L)、LY组(LY29400210μmol/L)。除对照组、LY组外,其余各组细胞均以Aβ1-42复制损伤模型。培养24 h后,使用显微镜观察各组细胞的形态,采用MTT法检测各组细胞的存活率;采用Western blotting法检测各组细胞PI3K、p-PI3K、Akt、p-Akt、GSK3β、p-GSK3β蛋白的表达情况。结果:与对照组比较,Aβ组细胞数量变少、部分突触断裂消失,其存活率以及p-PI3K/PI3K、p-Akt/Akt、p-GSK3β/GSK3β比值均显著降低(P<0.05或P<0.01)。与Aβ组比较,Aβ+SA组细胞变圆、突触变多,其存活率以及p-PI3K/PI3K、p-Akt/Akt、p-GSK3β/GSK3β比值均显著升高(P<0.05)。与Aβ+SA组比较,Aβ+SA+LY组细胞部分突触断裂,其存活率以及p-PI3K/PI3K、p-Akt/Akt、p-GSK3β/GSK3β比值均显著降低(P<0.05);Aβ+LY组细胞碎片较多,其存活率虽有下降但差异无统计学意义,且p-PI3K/PI3K、p-Akt/Akt、p-GSK3β/GSK3β比值亦无明显变化(P>0.05)。单独给予LY294002对PC12细胞的形态、存活率以及p-PI3K/PI3K、p-Akt/Akt、p-GSK3β/GSK3β比值均无显著影响(P>0.05)。结论:SA可能通过激活PI3K/Akt/GSK-3β信号通路对Aβ1-42诱导的PC12细胞损伤发挥保护作用。

OBJECTIVE:To investigate the mechanism of sinapic acid(SA)against PC12 cell injury induced by Amyloidβ1-42 protein(Aβ1-42)based on PI3K/Akt/GSK3βsignaling pathway.METHODS:PC12 cells of rats were randomly divided into control group,Aβgroup(Aβ1-422μmol/L),Aβ+SA group(Aβ1-422μmol/L+SA100μmol/L),Aβ+SA+LY group[Aβ1-422μmol/L+SA 100μmol/L+LY294002(PI3K inhibitor)10μmol/L],Aβ+LY group(Aβ1-422μmol/L+LY29400210μmol/L)and LY group(LY29400210μmol/L).Except for control group and LY group,the cells of other groups were replicated the damage model with Aβ1-42.After 24 hours of culture,the morphology of cells was obsened in each group with a microscope,and MTT assay was adopted to determine the cell viability of PC12 cells in each group.Western blotting assay was used to detect the expression of PI3K,p-PI3K,Akt,p-Akt,GSK3βand p-GSK3βin cells of each group.RESULTS:Compared with control group,the number of cells decreased and some synaptic breaks disappeared in Aβgroup while cell viability,ratio of p-PI3K/PI3K,p-Akt/Akt and p-GSK3β/GSK3βin Aβgroup were decreased significantly(P<0.05 or P<0.01).Compared with Aβgroup,the cells became round and synapses became more in Aβ+SA group while cell viability,the ratio of p-PI3K/PI3K,p-Akt/Akt and p-GSK3β/GSK3βwere increased significantly(P<0.05).Compared with Aβ+SA group,some synaptic breaks occurred in Aβ+SA+LY group while cell viability,the ratio of p-PI3K/PI3K,p-Akt/Akt and p-GSK3β/GSK3βwere decreased significantly(P<0.05);Aβ+LY group had more cell debris,and the cell viability was decreased,but the difference was not significant,and the ratio of p-PI3K/PI3K,p-Akt/Akt and p-GSK3β/GSK3βhad no significant change(P>0.05);LY294002 alone had no significant effect on morphology,cell viability and the ratio of p-PI3K/PI3K,p-Akt/Akt or p-GSK3β/GSK3β(P>0.05).CONCLUSIONS:SA may play a protective role against PC12 cell injury induced by Aβ1-42 through activating PI3K/Akt/GSK-3β.