促红细胞生成素对1-甲基-4-苯基吡啶损伤的PC12细胞的保护作用(英文)

目的探讨促红细胞生成素(erythropoietin,EPO)对1-甲基-4-苯基吡啶离子(MPP+)诱导的PC12细胞变性损伤的保护作用及机制。方法用MPP+处理PC12细胞制作帕金森病细胞模型,采用四甲基偶氮唑蓝法检测暴露于不同浓度EPO后细胞的活性;流式细胞术与DNA断端原位标记法(terminal deoxynucleotidyl transferase dUTPnick end labeling, TUNEL)检测各组的细胞凋亡率;免疫印迹法检测不同处理组PC12细胞Bcl-2和Bax的表达,并采用荧光法观察不同处理组PC12细胞活性氧(reactive oxygen species,ROS)与线粒体膜电位水平以及caspase-3活性的变化。结果 MPP+可以使PC12细胞存活率下降,凋亡率增高;同时PC12细胞内ROS增多,线粒体膜电位下降。MPP+还可以明显地提高Bax/Bcl-2比值并激活caspase-3。而EPO可以抑制这些由MPP+引发的改变,并在1 U/mL时发挥最大保护作用。结论 EPO可抑制MPP+诱导的PC12细胞死亡,其作用机制可能与其自身抗氧化和抗凋亡的特性有关。

Protective effect of erythropoietin against 1-methyl-4-phenylpyridinium-induced neurodegenaration in PC12 cells

Objective The neuroprotective effect of erythropoietin (EPO) against 1-methyl-4-phenylpyridinium (MPP+)-induced oxidative stress in cultured PC12 cells,as well as the underlying mechanism, were investigated. Methods PC12 cells impaired by MPP+ were used as the cell model of Parkinson's disease. Methyl thiazolyl tetrazolium (MTT) was used to assay the viability of the PC12 cells exposed to gradient concentrations of EPO,and the terminal deoxynucleotidyl transferase dUTP nick end labelling (TUNEL) assay was used to analyze the apoptosis ratio of PC12 cells.The expression of Bcl-2 and Bax in PC12 cells were examined by Western blot,and the reactive oxygen species (ROS),the mitochondrial transmembrane potential and the activity of caspase-3 in each group were detected by spectrofluorometer.Results Treatment of PC12 cells with MPP+ caused the loss of cell viability,which may be associated with the elevation in apoptotic rate,the formation of ROS and the disruption of mitochondrial transmembrane potential. It was also shown that MPP+ significantly induced the upregulation of Bax/Bcl-2 ratio and the activation of caspase-3.In contrast,EPO signifi-cantly reversed these responses and had the maximum protective effect at 1 U/mL. Conclusion The inhibitive effect of EPO on the MPP+-induced cytotoxicity may be ascribed to its anti-oxidative property and anti-apoptotic activity,and EPO may provide a useful therapeutic strategy for treatment of neurodegenerative diseases such as Parkinson's disease.