钙蛋白酶在 MPP+诱导的多巴胺能神经元损伤中的作用

摘要

Objective To investigate the role of calpain in dopaminergic neuronal injury induced by MPP+ .Methods PC12 cells were differentiated to sympathetic neuron-like cells by nerve growth factor.The cells were treated with MPP sessed by Western blot.The activity of calpain were determined by calpain activity assay kit.The effect of cal-pain inhibitor ALLN and MDL281 70 on cell viability was determined by MTT method.The apoptotic rate of PC12 cells were analysis by flow cytometry.Results After exposure to MPP calpainwere stable,while the expression of active calpain increased in a time-dependent manner.The activation of calpain also increased in a time-dependent manner,with peak activation at 12 h.The activation of calpain was inhibited by its inhibitor ALLN and MDL281 70.ALLN and MDL281 70 also attenuated the toxic effect of MPP+ on PC12 cells.Calpain inhibitors also inhibited cell apoptosis induced by by MPP pain plays importment roles in MPP kinson disease.+ for different times.The expression of total calpain and activated calpain were as-+ ,the expression level of total+ .Conclusions Cal-+-induced neuronal injury,and represent a novel therapeutic target for Parkinson disease.%目的：观察钙蛋白酶在 MPP+诱导的多巴胺能神经元损伤中的作用,探讨帕金森病的发病机制。方法使用神经生长因子诱导 PC12细胞神经元样分化,然后使用 MPP+处理神经元样分化的 PC12细胞,制作帕金森病细胞模型。使用免疫印迹法检测细胞内总钙蛋白酶和活化的钙蛋白酶的表达水平,使用钙蛋白酶活性检测试剂盒观察钙蛋白酶活化水平,使用钙蛋白酶抑制剂 ALLN 和 MDL 28170抑制钙蛋白酶活性后采用 MTT 法检测其对细胞活性的影响,用流式细胞术观察细胞凋亡变化。结果神经元样分化的PC12细胞经 MPP+处理后总的钙蛋白酶水平保持稳定,但活化的钙蛋白酶表达水平逐渐增高,钙蛋白酶活性也逐渐增高,MPP+处理12 h 后达到高峰。ALLN 和 MDL28170能够显著抑制钙蛋白酶活性,并减轻MPP+诱导的 PC12细胞损伤。钙蛋白酶抑制剂也能够明显抑制 MPP+诱导的细胞凋亡。结论钙蛋白酶参与 MPP+诱导的多巴胺能神经元损伤,可能是帕金森病新的治疗靶点。