神经干细胞移植联合脑源性神经营养因子局部注射对老年性痴呆鼠海马线粒体膜电位及行为学的影响

Neural stem cells plus brain-derived neurotrophic factor to influence the ethology and mitochondrion membrane potential in the hippocampus of Alzheimer’s disease rats

背景:移植神经干细胞的分化受移植部位微环境、各种生长及细胞因子的影响。目的:实验拟观察神经干细胞移植与脑源性神经营养因子联合应用对老年性痴呆鼠行为学恢复及海马线粒体膜的影响。设计、时间及地点:随机对照动物实验,于2006-09/2007-09在重庆医科大学动物实验室及细胞实验室完成。材料:神经干细胞来源于新生1d龄SD大鼠。Y迷宫筛选对电击敏感并逃避迅速的三四月龄健康雄性SD大鼠,随机分成4组:正常对照组、神经干细胞组、脑源性神经营养因子组、联合组移植,每组10只。方法:分离培养大鼠神经干细胞。参照包新民等的大鼠脑立体定位图谱制备老年性痴呆大鼠模型。造模后,神经干细胞组双侧海马区注射神经干细胞,脑源性神经营养因子组双侧海马区注射脑源性神经营养因子,联合移植组注射神经干细胞同时持续侧脑室注射脑源性神经营养因子。主要观察指标:用分子生物学检测老年性痴呆大鼠海马线粒体膜电位的变化,行Y迷宫试验观察大鼠行为学中学习记忆能力。结果:联合移植组老年性痴呆大鼠海马线粒体膜电位明显升高,并高于神经干细胞组、脑源性神经营养因子(P<0.05),与正常对照组比较无明显差异。脑源性神经营养因子组、神经干细胞组学习记忆能力虽有明显恢复,但与联合移植组和正常对照组比较还有一定的距离(P<0.05)。结论:神经干细胞与脑源性神经营养因子联合应用能能稳定海马线粒体功能,从而抑制神经细胞凋亡,能改善老年性痴呆鼠的学习记忆功能障碍。

BACKGROUND： The survival of transplanted neural stem cells （NSCs） in host＇s brain is affected by the microenvironment in transplantation site, growth factors and cytokine. OBJECTIVE： To observe the influence of NSCs transplantation combined with brain-derived neurotrophic factor （BDNF） in the ethology recovery and hippocampal mitochondria membrane of Alzheimer＇s disease rats. DESIGN, TIME AND SETTING： Randomized control animal experiment was carried out in the Animal Laboratory and Cell Laboratory of Chongqing Medical University （Chongqing, China） from September 2006 to September 2007. MATERIALS： NSCs were from neonatal 1-day SD rats. Healthy male SD rats, aged 3-4 months, which were sensitive to lightning stroke and rapid escaping in Y maze were randomly divided into 4 groups： normal control group, NSCs group, BDNF group and combined transplantation group, with 10 rats of each group. METHODS： NSCs were isolated from SD rats and then cultured. The rat model of Alzbeimer＇s disease was induced according to rat stereotaxic atlas ofBao Xin-min, et al. Then NSCs, BDNF and combined application of the two were injected bilaterally into the bippocampal zone of corresponding groups. MAIN OUTCOME MEASURES： Four weeks later, Y maze was used to test the abilities of learning and memory of the rats; Molecular biology was used to measure the change of hippocampal mitochondria membrane potential in rats. RESULTS： In the NSCs group and BDNF group, the learning and memory abilities of the rats recovered obviously, but there was still a long way to go for the combined transplantation group and normal control group （P 〈 0.05）. Combined transplantation of NSCs and BDNF raised the mitochondria membrane potential obviously, which was much higher than that in the NSCs group and BDNF group （P 〈 0.05）, and there were no significant differences compared to the normal control group. CONCLUSION： NSCs combined with BDNF can stabilize the hippocampal mitocbondria function, inhibit the apoptosis of nerve cells, and improve the learning and memory abilities of Alzbeimer＇s disease rats.