目的:研究芝麻素对NMDA所致原代培养小鼠皮层神经元损伤的保护作用及其机制。方法:体外培养原代皮层神经元;免疫荧光染色鉴定细胞纯度;MTT法测定细胞存活率;Hoechst/PI双染色观察细胞凋亡的形态学变化;激光共聚焦显微镜技术观察钙成像,检测细胞内钙离子浓度变化;Western blot检测各组细胞中Bcl-2、Bax、NR2A、NR2B蛋白的表达。结果:NMDA(200μM)60分钟能使神经元细胞存活率显著下降,细胞凋亡百分比明显增加(P〈0.01),芝麻素(0.1μM)能提高细胞存活率,减少细胞凋亡(P〈0.01)。与NMDA组相比,芝麻素能抑制钙超载;降低Bax和NR2B蛋白表达;增加和Bcl-2蛋白表达(P〈0.01)。结论:芝麻素具有神经保护作用,这种作用可能与抑制钙超载、下调NMDA受体亚型NR2B的表达以及调节Bcl-2家族蛋白有关。
Objective: To investigate the protective effect as well as mechanisms involved in the neuroprotective effects of Sesamin (SE) on primary cultured cortical neural injury induced by N-methyl-D-aspartate (NMDA). Methods: NMDA was added to the medium of cultured cortical neurons culture in vitro. MTT assay was used to detect cell viability. Hoechst 33258 and propidium iodide (PI) double fluorescent staining was used to assess cellular morphological changes of apoptosis. Calcium imaging was performed to detect the change of Ca2+ concentration by using a confocal laser scanning microscope. Protein expression of Bcl-2, Bax, NR2A, NR2B in neurons of each group was detected by Western blot. Results: After treat with NMDA for 60 min, loss of cell survival rate and increase of cell apoptotic rate were observed(P〈0.01). Compared with NMDA group, Sesamin(0.1 μM) could reverse calcium overload, decrease the expression level of Bax and NR2B and increase the expression level of Bcl-2(P〈0.01). Conclusions: Sesamin confers neuroprotective effects which may be by inhibiting intracellular calcium overload, and down regulating the expression of NR2B-containing NMDA receptors, and regulating the Bcl-2 family.