GSH对体外培养海马神经元氧应激状态的双相调控作用

Study on the effect of GSH on oxidative stress in cultured hippocampus neurons

目的:探讨还原型谷胱苷肽GSH(glutathione)对海马神经元氧应激状态的影响及可能机制。方法:利用H2O2诱导建立了海马神经细胞氧应激的实验模型,H2O2的剂量为0.1nM.GSH取4个剂量(分别为0.2mM,2mM.20mM,200mM),通过形态学观察、图像分析细胞光密度MOD(matrixopticaldensity)检测添加GSH对海马神经元氧应激的影响,利用DTNB比色法测定氧化型谷胱苷肽GSSG、总GSH(GSH+GSSG)含量及GSSG/GSH比值。结果:GSH组的海马神经元光密度与单纯H2O2组有显著性差异。加入GSH对海马神经元GSSG、GSH含量及比值的影响:较低剂量的GSH可以显著降低H2O2所致的GSSG的升高,而当GSH剂量高于20mM时,GSSG含量与H2O2组无显著性差异。从GSSG/GSH比值上看,较低剂量的GSH可以显著降低GSSG/GSH的比值,而当GSH剂量达到20mM时,GSSG/GSH比值与H2O2组无显著性差异。结论:抗氧化剂GSH对于H2O2诱导的体外培养海马神经元的氧应激状态具有双相作用,即较低剂量GSH可以逆转这种氧应激,而较高剂量则没有表现出明显的逆转作用。

Objective： To study the effect of GSH on oxidative stress in cultured hippocampus neurons. Methods： We founded a model of oxidative stress in hippocampal cells by adding H2O2 in cultured-medium. Four different doses of GSH were selected in the experiment. GSH was studied on this model by examination of the morphological changes of cells and the index of matrix optical density （MOD）. The level of GSSG and GSH were mensurate by DTNB colorimetry. Results：The MOD index of GSH group neurons were significantly different from H2O2 group. The lower doses of GSH could rescue cells from toxic effects of hydroxyl radical generated by H2O2, while the dose of GSH raised 20mM, the effect was reduced. Conclusion： A dual response was found. GSH in lower doses may play an important role in neuroprotection. Excessive doses of GSH have no effect on the free radical damage of cultured cells.