脑缺血再灌注损伤后神经细胞巢蛋白和干细胞因子基因的表达(英文)

Nestin and stem cell factor mRNA expression in neurons after rat cerebral ischemia-reperfusion injury

背景:干细胞因子是缺氧诱导的神经再生因子,可能刺激动物的神经再生。目的:观察大鼠脑缺血再灌注损伤后神经细胞巢蛋白和干细胞因子基因表达的变化,分析两者变化的时间规律。设计:随机对照动物实验。单位:青岛大学医学院附属医院超声诊断科。材料:实验选用成年健康雌性SD大鼠36只,由中国科学院上海实验动物中心提供。实验所用巢蛋白和干细胞因子mRNA原位杂交试剂盒、DAB试剂盒均由武汉博士德生物工程有限公司提供。方法:实验于2005-01/06在山东省脑病防治重点实验室完成。选取32只大鼠,应用线栓法经左侧颈外一颈内动脉插线建立左侧大脑中动脉阻塞再灌注模型,在缺血1.5h再灌注后2,6,12,24h,2,3,7,14d进行观察,每个时间点4只。其余4只为假手术组:除不插线外,其余步骤同实验组。应用原位杂交技术检测脑缺血再灌注后皮质、纹状体和室旁区巢蛋白和干细胞因子mRNA的表达。主要观察指标:大鼠皮质、纹状体和室旁区神经细胞巢蛋白和干细胞因子基因表达。结果:进入结果分析数量保持为36只。①巢蛋白mRNA表达:假手术组皮质、纹状体和室旁区巢蛋白mRNA表达很弱。缺血再灌注后,在皮质中的表达除再灌注后2h、纹状体除再灌注后2,6h以外,室旁区除2,6h,14d以外各时间点均明显高于假手术组,差异有显著性意义(P<0.05)。②干细胞因子表达:假手术组皮质、纹状体和室旁区干细胞因子表达很弱。缺血再灌注后,在皮质中的表达除2,6,12h以外,纹状体除2,6h以外,室旁区除2h,14d以外各时间点均明显高于假手术组,差异有显著性意义(P<0.05)。结论:干细胞因子表达的时间规律与神经干细胞增殖的时间规律基本一致,可以提示脑缺血再灌注后干细胞因子mRNA表达可能具有促进神经干细胞增殖作用。

BACKGROUND： Stem cell factors are hypoxia-induced neural regeneration factors. They stimulate animals＇ neural regeneration. OBJECTIVE： To observe Nestin and stem cell factor mRNA expressions after ischemia/reperfusion injury in rat brain, and to analyze the time rule of the two. DESIGN： A randomized controlled animal experiment. SETTING： Department of Ultrasound Diagnosis, Affiliated Hospital of Qingdao University Medical College. MATERIALS： Thirty-six healthy female adult Sprague-Dawley （SD） rats were provided by the Shanghai Laboratory Animal Center, Chinese Academy of Science. Nestin and stem cell factor mRNA in situ hybridization kits and 3,3＇-diaminobenzidine （DAB） kit were provided by Boster Bioengineering Co.,Ltd （Wuhan, China）. METHODS： This study was performed at the Shangdong Key Laboratory for Prevention and Treatment of Encephalopathy from January to June 2005. Thirty-two rats were created into models of ischemia/reperfusion models by occluding left middle cerebral artery with suture. At ischemia 1.5 hours and reperfusion 2, 6, 12, 24 hours, 2, 3, 7, 14 days, 4 rats were separately used in order to observe the expressions of Nestin and stem cell factor mRNA. The other 4 rats were used for sham-operation, in which, suture insertion was omitted, and the other procedures were identical to experimental groups. The expressions of Nestin and stem cell factor mRNA were detected in the cortex, corpora striatum and paraventricular nucleus region in rat brain by in situ hybridization. MAIN OUTCOME MEASURES： Nestin and stem cell factor mRNA expressions in the cortex, corpora striatum and paraventricular nucleus region in rat brain. RESULTS： Thirty-six rats were included in the final analysis. Nestin mRNA and stem cell factor were weakly expressed in the cortex, corpora striatum and paravenWicular nucleus region in rats of sham-operation group. After ischemia/reperfusion, Nestin mRNA expression at each time point was significantly higher in the experimental groups （except in the cortex at ischemia 1.5 hours and reperfusion 2 hours, in the corpora striatum at ischemia 1.5 hours and reperfusion 2 and 6 hours and in the paraventricular nucleus region at ischemia 1.5 hours and reperfusion 2, 6 hours and 14 days） than in the sham-operation group （P 〈 0.05）. While stem cell factor mRNA expression at each time point was significantly higher in the experimental groups （except in the cortex at ischemia 1.5 hours and reperfusion 2,6 and 12 hours, in the corpora striatum at ischemia 1.5 hours and reperfusion 2 and 6 hours and in the paraventricular nucleus region at ischemia 1.5 hours and reperfusion 2 hours and 14 days） than in the sham-operation group （P 〈 0.05）. CONCLUSION： The time rule of stem cell factor mRNA expression is basically the same as that of neural stem cell proliferation. It indicates that following cerebral ischemia/reperfusion, stem cell factor mRNA expression may promote the proliferation of neural stem cells.