尼古丁上调星形胶质细胞内源性Cryab抑制Aβ聚集的研究  

Nicotine inhibit Aβ aggregation via upregulation endogenous Cryab in astrocytes

作　　者：任真奎 杨梅[1] 官志忠[1,2] 禹文峰[1] 

机构地区：[1]贵州医科大学医学分子生物学重点实验室,贵州贵阳550004 [2]贵州医科大学病理学教研室,贵州贵阳550004

出　　处：《中风与神经疾病杂志》2016年第10期897-900,共4页Journal of Apoplexy and Nervous Diseases

基　　金：国家自然科学基金(批准号:81360199);教育部科学技术研究项目(批准号:213032A);贵州省国际科技合作计划项目[批准号:黔科合外G字(2013)7026号];贵州省创新计划项目[黔教合协同创新中心(2014)06]

摘　　要：目的研究尼古丁激活星形胶质细胞α7胆碱能受体(α7 nicotinic receptors,7 n AChRs)上调内源性B-晶状体蛋白(αB-crystallin,Cryab)并抑制β淀粉样蛋白(Amyloid,Aβ)集聚的现象及其机制。方法分离24 h内新生乳鼠大脑皮质培养原代星形胶质细胞并鉴定;体外制备Aβ_(1-42)寡聚体;将细胞分为对照组、尼古丁组、α7n AChRs阻断剂(methyllycaconitine,MLA)组、Aβ_(1-42)组、尼古丁+Aβ_(1-42)组、PI3K信号通路阻断剂LY294002+尼古丁+Aβ_(1-42)组。用蛋白印迹法(Western blotting)检测细胞内Cryab、P-Akt(ser473)、Aβ寡聚体的表达水平。结果尼古丁可以显著上调星形胶质细胞内源性Cryab蛋白(P<0.05);尼古丁能够显著上调磷酸化Akt蛋白水平(P<0.05);在细胞裂解液及培养基中,尼古丁显著增强星形胶质细胞对Aβ聚集的抑制作用(P<0.01)。结论尼古丁通过激活星形胶质细胞α7 nAChRs上调内源性Cryab从而抑制Aβ集聚;PI3K/Akt信号通路可能参与尼古丁激活星形胶质细胞α7 n AChRs上调内源性Cryab蛋白抑制Aβ集聚的过程。为进一步研究尼古丁抑制Aβ集聚的可能机制提供了实验基础。Objective To investigate the possible mechanism of nicotine on amyloid β（ Aβ） aggregation via activa-tionα7 nAChRs as well as upregulation endogenous Cryab .Methods Primary astrocytes culture were separated from neo-natal SD rat cerebral cortex;Aβ1-42 oligomers were prepared in vitro .The astrocytes were divided into control group ,nicotine group,MLA group,Aβ1-42group,nicotine ＋Aβ1-42group,nicotine ＋LY294002＋Aβ1-42 group.The protein levels of Cryab, phosphorylated-Akt （ ser473 ） and Aβoligomers in the cells was detected by Western blot .Results Nicotine significantly increased endogenous Cryab in astrocytes （P〈0.05）.Nicotine significantly increased phosphorylated-Akt in astrocytes.In cell lysis solution and medium,Nicotine significantly enhanced astrocyte to inhibit Aβaggregation （P〈0.01）.Conclusions Nicotine can significantly inhibit Aβaggregation via activated α7 nAChRs as well as upregulation endogenous Cryab in astrocytes.PI3K/Akt signaling pathway is likely to be involved in this process .This study provided experimental data on the possible mechanism of nicotine inhibit Aβaggregation .

关 键 词：星形胶质细胞 阿尔茨海默氏病 α7胆碱能受体 尼古丁 B-晶状体蛋白 Β淀粉样蛋白 

分 类 号：R749.1[医药卫生—神经病学与精神病学]