髓鞘结合糖蛋白抑制神经干细胞向神经元分化和轴突生长  

Myelin-associated glycoprotein inhibits the differentiation and neurite growth of neural stem cells

作　　者：李欣[1] 廖新学[2,3] 冯鉴强[4] 荆小莉[1] 杨春涛[4] 熊艳[1] 李玉杰[1] 廖晓星[1] 

机构地区：[1]中山大学附属第一医院急诊科 [2]中山大学附属第一医院心血管内科 [3]中山大学附属第一医院高血压血管病科 [4]中山大学中山医学院生理教研室,广东广州510080

出　　处：《中国病理生理杂志》2009年第5期919-923,共5页Chinese Journal of Pathophysiology

基　　金：广东省科技计划资助项目(No.2006B36004010)

摘　　要：目的:观察来源于胚胎大鼠海马神经细胞的特征;观察髓鞘结合糖蛋白(MAG)对神经干细胞的增殖、分化及神经元轴突生长的影响。方法:从胚胎鼠的海马提取细胞进行体外培养,应用免疫荧光染色法检测神经干细胞(NSCs)标志蛋白nestin和doublecortin的表达。应用BrdU掺入法检测不同剂量的MAG-Fc对NSCs增殖的影响。免疫荧光染色法观察各种亚型神经细胞的比例并比较神经元样细胞的轴突长度。结果:来自SD大鼠16d胚胎海马的细胞明显表现出神经干细胞的特征。神经干细胞分化7d后,对照组新生成的β-tubulinⅢ阳性细胞的比例为18.17%±2.79%,其轴突长度为(136.27±33.66)μm。MAG-Fc(200μg/L)处理后,β-tubulinⅢ阳性细胞比例和轴突长度分别显著减少为10.05%±3.42%(P<0.01)和(84.87±24.94)μm(P<0.01)。增殖实验表明,不同浓度的MAG-Fc对神经干细胞的BrdU整合比率无明显影响(P>0.05)。结论:MAG-Fc对神经干细胞向神经元样细胞的分化及其轴突的生长均有抑制作用,但对神经干细胞的增殖无明显影响。AIM： To observe the characterization in neural cells derived from the hippocampus of embryonic rats and to examine the effect of myelin - associated glycoprotein （MAG） on the proliferation, differentiation and neurite growth of neural stem cells （NSCs）. METHODS ： The hippocampus cells of embryonic rats were isolated and cultured in vitro. The expressions of nestin and doublecortin, the marks of NSCs, were observed by immunocytochemieal method. The rate of proliferating cells was examined by BrdU immunocytochemistry. The average neuronal neurite length and the percentage of differentiated neurons were detected by immunocytochemistry staining. RESULTS： The hippocampus cells of 16 days old embryonic rats had the characteristics of NSCs. The percentage of differentiated neurons （ 13 - tubulin Ⅲ - positive cells） was 18. 17 % ±2. 79% and the average neuronal neurite length was （136. 27± 33.66）μm, seven days after the differentiation initiated in vitro in control group. After NSCs were treated with MAG - Fe （200 μg/L）, the percentage of differentiated neurons and the average neurite length were decreased, respectively, to 10. 05% ± 3.42% （ P 〈 0. 01 ） and （84. 87 ±24.94）μm （P 〈0. 01）. The results from proliferation test indicated that the rate of BrdU incorporation did not changed after the treatment of MAG - Fc with different dosages （ P 〉 0. 05 ）. CONCLUSION： MAG - Fc inhibits the differentiation and neurite growth of the NSCs, but has no effect on the proliferation.

关 键 词：神经干细胞 髓磷脂相关糖蛋白 轴突 

分 类 号：R681.5[医药卫生—骨科学]