淀粉样β蛋白对小胶质细胞活化作用的体外观察  

Beta-amyloid protein activates microglia in vitro

作　　者：聂永慧[1] 王鲁宁[1] 贾建军[1] 王录焕[2] 张晓娟[2] 张炳烈[3] 房征宇[3] 

机构地区：[1]解放军总医院老年神经内科,北京市100853 [2]解放军总医院生化实验室,北京市100853 [3]解放军总医院老年医学研究所,北京市100853

出　　处：《中国临床康复》2005年第29期70-72,共3页Chinese Journal of Clinical Rehabilitation

摘　　要：目的:观察淀粉样β蛋白对小胶质细胞活性、形态学以及分泌炎性细胞因子的作用,为阿尔茨海默病的炎性反应机制及抗炎治疗提供体外依据。方法:实验于2003-03/2004-03在解放军总医院老年医学研究所进行。应用BV-2细胞作为体外小胶质细胞模型,加入不同浓度淀粉样β蛋白25～35或1～42(5,10,20,40,60μmol/L)及20μmol/L不同孵育状态(37℃孵育3,6,12,24h、3,5和7d)的淀粉样β蛋白25～35或1～42分别培养2～24h。四唑盐法检测淀粉样β蛋白对细胞活性的影响,倒置相差显微镜下观察细胞形态学改变,并应用放射免疫法测定加入淀粉样β蛋白后BV-2细胞上清白细胞介素1β及白细胞介素6水平。结果:①细胞活性:淀粉样β蛋白对BV-2细胞的生存活性没有影响(P均>0.05)。②细胞形态学改变:在较低浓度时(5～10μmol/L)淀粉样β蛋白1～42就可以使BV-2细胞出现明显的形态学改变(多数细胞聚集成团,有的胞体变得肥大,胞核大而圆,核仁明显;有的胞体变为梭形,由胞体伸出一个或多个较长的枝状突起),与淀粉样β蛋白1～42孵育状态有关(37℃孵育5～7d时最为明显),而淀粉样β蛋白25～35无此作用。③白细胞介素1β水平:淀粉样β蛋白1～42与25～35均可以刺激BV-2细胞分泌,二者作用类似。20μmol/L淀粉样β蛋白作用6h后其水平升高,至12h达到高峰,约为对照组的3倍,此后逐渐下降(P<0.01)。当不同浓度淀粉样β蛋白作用12h时,淀粉样β蛋白为20μmol/L时在上清中可以检测到白细胞介素1β明显增加,此后随着浓度的增加其分泌也逐渐增加,至60μmol/L时为对照组的5倍(P<0.01)。④白细胞介素6水平:各淀粉样β蛋白处理组细胞上清液均不能检测到其水平有明显变化。结论:淀粉样β蛋白对BV-2细胞的生存活性没有影响,淀粉样β蛋白可以激活BV-2细胞发生形态学改变并释放炎性细胞因子,但二者的作用途径不同,形态学改变与淀粉样β蛋AIM： To investigate the role of beta-amyloid （Aβ） protein on activity, morphological changes and secretion of proinflammatory cytokines of microglia （MG） so as to provide in vitro bases for the mechanism of inflammatory reaction of Alzheimer disease and the anti-inflammatory treatment. METHODS： The experiment was conducted in Institute of Geriatrics, General Hospital of Chinese PLA from March 2003 to March 2004. The BV-2 cells （cell models of MG in vitro） were treated with Aβ25-35 and Aβ1-42 at different concentration（5, 10, 20, 40 and 60μmol/L） or Aβ25- 35 and Aβ1-42 at 20μmol/L under different incubation condition（at 37℃ for 3, 6, 12, 24 hours, 3, 5 and 7 days） for 2 to 24 hours. The influence of Aβ protein on the activity of cells were assayed by methylthiazolyl-tetrazolium （MTT）. The morphological changes of cells were observed underan inverted phase contrast microscope. The levels of proinflarmnatory cytokines interleukin （IL）-Iβ and IL-6 in BV-2 cell suspension after added with Aβ protein by radioimmunoassay. RESULTS： ①The activity of BV-2 cells： Neither peptide of Aβ1-42 nor Aβ2.5-35 had influence on the survival BV-2 cells （both P 〉 0.05）. ② Morphological changes of cells： BV-2 cells had remarkable changes of their form after treatment with Aβ1-42 at low concentration （5 to 10μmol/L） （Much of them were aggregated, some of which showed hypertrophic with distinct nucleoli, and some had their shape changed as one or more branch-shaped multiple processes）, in correlation with the incubation of Aβ1-42（at 37℃ for 5 to 7 days were the most obvious）. However, Aβ25- 35 had no effect on the form of BV-2 cells. ③The level of IL-1β： Both Aβ1-42 and Aβ25-35 could stimulate secretion of IL-1β from BV-2 cells in the same manner. The level of IL-1β increased after stimulated with 20 μmol/L Aβ for 6 hours, peaked at 12 hours （as about 3 times as in control group）, and then decreased gradually（P 〈 0.01）. The level of IL-1β

关 键 词：淀粉样Β蛋白 小神经胶质细胞 体外研究 

分 类 号：R741[医药卫生—神经病学与精神病学]