【摘要】 目的观察大鼠胰岛细胞对高糖损伤是否存在记忆效应,并对其机制进行初步探讨。方法以INS-1(大鼠胰岛瘤细胞株)细胞作为研究对象,观察INS-1细胞经历48 h持续高糖(33.3 mmol/L)刺激后,纠正高糖状态,以11.1 mmol/L糖浓度继续培养,检测细胞活力,凋亡相关基因(bax,caspase-3)的mRNA水平和活性氧(ROS)水平的变化。INS-1细胞处理组分为:对照组(11.1 mmol/L葡萄糖×7 d);高糖组(33.3 mmol/L葡萄糖×2 d);3 d记忆组(33.3 mmol/L葡萄糖×2 d+11.1mmol/L葡萄糖×3 d);5 d记忆组(33.3 mmol/L葡萄糖×2 d+11.1 mmol/L葡萄糖×5 d)。Real-Time PCR检测bax,cas-pase-3的mRNA水平,Dihydroethidium(DHE探针)检测ROS水平,MTT法测定细胞活力。结果高糖组细胞活力较对照组显著降低(P<0.001)。而ROS水平,bax,Caspase-3的mRNA水平较对照组显著增高(P<0.05)。在3 d记忆组及5 d记忆组,细胞活力较对照组显著降低(P<0.001),ROS水平,bax,Caspase-3的mRNA水平较对照组显著增高(P<0.05)。结论高糖对INS-1细胞的损伤存在记忆效应,主要表现为细胞活力的持续降低,促凋亡基因的持续高表达。ROS水平的持续升高可能与记忆效应产生有密切关系。更多还原

【Abstract】 Objective To investigate the cellular memory of previous high glucose exposure in rat islet cell line(INS-1) and explore the possible mechanism.Methods INS-1 cells were exposed to a high glucose(33.3 mmol/L) culture for 48 h followed by further culture in the presence of 11.1 mmol/L glucose in the culture medium for 3 or 5 days.The levels of bax and caspase-3 mRNA were measured by real-time PCR,the production of reactive oxygen species(ROS) was assayed using the dihydroethidium probe,and the cell viability was detected by MTT assay.Results High glucose exposure of the cells for 48 h resulted in significantly increased ROS production and bax and caspase-3 mRNA expressions and lowered cell viability(P<0.001).In cells cultured in 11.1 mmol/L glucose following previous high glucose exposure,the ROS production and bax and caspase-3 mRNA expressions still maintained the high levels(P<0.05) while the cell viability remained significantly lower than the control cells(P<0.001).Conclusion High glucose causes persistent changes in cell viability and apoptosis-related gene expressions even after recovery of normoglycemia,the mechanism of which is probably related to increased ROS production.更多还原