洛伐他汀减轻NMDA诱导的兴奋性毒性损害

Lovastatin attenuates NMDA induced excitotoxicity in rat cortical neurons

目的探讨洛伐他汀(Lovastatin,LOV)对NMDA诱导的大鼠皮质神经元兴奋性毒性损害的神经保护作用。方法选用胚胎17d的SD大鼠,取皮质神经元接种培养。通过台盼蓝排除实验评估细胞活力、TUNEL染色检测凋亡细胞及免疫荧光细胞化学技术测定神经元形态。结果台盼蓝排除实验显示500nmol/L洛伐他汀预处理3d显著减轻NMDA诱导的大鼠皮质神经元兴奋性毒性损害,而不能减少蛋白激酶C抑制剂星形孢菌素诱导的细胞凋亡。LOV和L-甲羟戊酸(MVA)共同预处理不能减轻NMDA诱导的兴奋性毒性损害,提示其保护作用依赖于降低胆固醇水平。洛伐他汀的神经保护作用呈剂量和时程依赖性。TUNEL染色显示洛伐他汀预处理能减少NMDA诱导的细胞凋亡。免疫荧光细胞化学结果显示洛伐他汀能改善NMDA诱导的MAP-2神经元形态损害。结论洛伐他汀选择性地减轻NMDA诱导的大鼠皮质神经元兴奋性毒性损害及形态损害,提示洛伐他汀对兴奋性毒性损害相关神经病理有潜在的神经保护作用。

Objective To observe the effect of lovastatin on NMDA induced excitotoxicity in rat cortical neurons.Methods Cortical neurons were prepared from E17 rat.Cell viability was evaluated with typan blue dye exclusion test,apoptosis was detected with TUNEL staining,and the morphology and number of neurons was assessed with MAP-2 immunofluorescence staining.Results Typan blue staining demonstrated that 500 nmol/L lovastatin pre-treatment 3d significantly and selectively protected neurons against NMDA induced excitotoxicity but not against staurosporine induced apoptosis.The protective effects were completely abolished co-treated with lovastatin and MVA,indicating protection was dependent on cholesterol-lowering.Moreover,protection of lovastatin was dosage-and time-dependent.In line with this evidence,lovastatin decreased apoptosis upon NMDA by TUNEL staining.Immunofluorescence staining demonstrated the number of MAP-2 positive neurons decreased and survival neurons showed a loss of MAP-2 positive dendrites after NMDA treatment,which were not visible after lovastatin pre-treatment.Conclusions Lovastatin significantly and selectively attenuated NMDA induced excitotoxicity,indicating that lovastatin has potential neuroprotective effects on excitotoxicity-related neuropathology.