N-乙酰半胱氨酸对G/GO诱导hRPE细胞氧化损伤的保护作用

The protective effect and mechanism of N-acetylcysteine on glucose/glucose oxidase induced human retinal pigmental epithelial cells

目的探讨N-乙酰半胱氨酸(NAC)对葡萄糖/葡萄糖氧化酶(G/GO)氧化损伤人视网膜色素上皮(hRPE)细胞的影响及其机制。方法用不同浓度的GO在高糖条件下处理hRPE细胞,建立葡萄糖氧化而损伤细胞的模型。应用四甲基偶氮唑蓝(MTT)比色法检测细胞存活率;双氢罗丹明123(DHR)染色后流式细胞仪检测细胞内活性氧(ROS)水平;Western blot检测细胞诱导型一氧化氮合酶(iNOS)的蛋白表达。结果GO(5-20 mU)处理hRPE细胞6h,可呈剂量依赖性地降低hRPE细胞的存活率;加入NAC可明显抑制G/GO引起的细胞存活率降低,减少G/GO引起的细胞内ROS堆积以及iNOS蛋白的表达。结论NAC能显著地减轻G/GO对hRPE细胞的氧化损伤作用;其作用机制可能与减少ROS的堆积,抑制iNOS的活性有关。

Objective To investigate the effects of N-acetylcysteine（NAC） on Glucose/Glucose oxidase（G/GO） induced human Retinal pignent epithelium（hRPE） cells damage and its mechanisms. Methods hRPE cells were treated with different concentrations of GO as an in vitro oxidative stress model. The cell viability was measured by MTT assay. Intercellular reactive oxygen species （ROS） was detected by dihydrorhodamine123 （DHR） staining and flow cytometric analysis. The changes of iNOS expressed were studied with Western blot in aquantitative way. Results GO at concentrations of 5 mU to 20 mU dose-dependently decreased hRPE cells viability. After treated with NAC, the inhibition of cell viability and ROS accumulation were significantly attenuated, and iNOS expression was significantly inhibited. Conclusion NAC obviously protects hRPE cells against G/GO induced oxidative damage by inhibiting accu- mulation of intracellular ROS and iNOS activity.