电针通过抑制小鼠缺血半暗带NDRG2表达发挥神经保护作用

Electroacupuncture protects brain from ischemic injury via inhibiting NDRG2 in ischemic penumbra in mice

目的:探讨NDRG2在电针预处理神经保护作用中的机制。方法:小鼠缺血半暗带区注射NDRG2过表达病毒(NDRG2)及其对照病毒(Vector)或NDRG2干扰病毒(si-NDRG2)及其对照病毒(si-control),4周后转染了NDRG2过表达病毒组小鼠的行30 min电针后2 h取脑组织进行Western Blot检测,转染了si-NDRG2病毒组的小鼠灌注取脑进行免疫荧光染色,分别验证病毒转染是否成功。NDRG2过表达和Vector组每组各9只小鼠进行30 min电针,2 h后实施大脑中动脉缺血(middle cerebral artery occlusion,MCAO),si-NDRG2组直接行MCAO,1 h后恢复脑血流。缺血再灌注后24、48 h和72 h行神经功能学评分,结束后取脑组织计算梗死容积。结果:缺血半暗带区过表达NDRG2可以逆转电针引起的减小梗死容积、改善神经行为学评分的神经保护作用,而抑制NDRG2表达则可模拟电针的神经保护作用。结论:电针通过抑制NDRG2表达发挥神经保护作用。

Objective： To explore the mehanism of NDRG2 in neuroprotective effect of electroacupuncture（ EA）pretreatment. Methods： The NDRG2 overexpression virus and its control vector virus,as well as the NDRG2 interference virus and its control virus,were injected into the ischemic penumbra. Four weeks later,part of mice in the NDRG2 overexpression group were sacrificed at 2 h after cessation of 30 min EA for Western Blot,and part of mice in the NDRG2 interference group were sacrificed for immunofluorescence to verify the efficiency of virus transfection. Two hours after EA（ 30 min）,the rest mice in the NDRG2 overexpression group were subjected to middle cerebral artery occlusion（ MCAO,1 h）,the NDRG2 interference group and the control group were executed to MCAO without EA.The neurological behavioral score was tested at 24 h,48 h and 72 h after MCAO and then the cerebral infarct volume was evaluated at the 72 h after MCAO. Results： Overexpression of NDRG2 attenuated the neuroprotective effect of the EA,as demonstrated by increasing of infarct volume and deterioration of neurological behavioral score,and inhibition of NDRG2 expression mimiced the neuroprotective effect of EA. Conclusion： EA pretreatment protects brain from ischemic injury by suppressing NDRG2 in ischemic penumbra.