PNU上调大鼠皮质星形胶质细胞内源性Cryab抑制Aβ聚集  

PNU inhibiting Aβ aggregation via upregulation endogenous Cryab in rat astrocytes

作　　者：任真奎 杨梅[1] 官志忠[1] 禹文峰[1] REN Zhen-Kui YANG Mei GUAN Zhi-Zhong(Key Lab of Medical Molecular Biology, Guizhou Medical University, Guiyang 550004, Guizhou, Chin)

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

出　　处：《中国老年学杂志》2016年第22期5506-5509,共4页Chinese Journal of Gerontology

基　　金：国家自然科学基金(81360199);教育部科学技术研究项目(213032A);贵州省国际科技合作计划项目(黔科合外G字〔2013〕7026号);贵州省教育厅项目(2015年贵州省普通高等学校地方病和少数民族疾病防控创新团队)

摘　　要：目的探讨PNU激活星形胶质细胞a7胆碱能受体（a7 nAChRs）上调内源性B-晶状体蛋白（Cryab）并抑制β淀粉样蛋白（Aβ）集聚的现象及其机制。方法分离24h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Aβ1-42寡聚体；将细胞分为对照组、PNU组、PNU＋a7nAChRs阻断剂（MLA）组、Aβ1-42组、PNU＋Aβ1-42组、PBK信号通路阻断剂LY294JD02＋PNu＋ANU-Aβ1-42组。用蛋白印迹法检测细胞内Cryab、P·Akt（set473）、AB寡聚体的表达水平。结果（1）PNU可以显著上调星形胶质细胞内源性Cryab蛋白（P〈0．05）；应用MLA阻断a7 nAChRs后，PNu上调内源性Cryab蛋白的作用被显著抑制（P〈0．05）；使用LY294002阻断PBK信号通路后，PNU上调内源性Cryab蛋白的作用被显著抑制（P〈0．01）；（2）PNU能够显著上调磷酸化Akt蛋白水平（P〈0．05）；应用MLA阻断a7nAChRs后，PNU上调磷酸化Akt蛋白的作用被显著抑制（P〈0．01）；使用LY294002阻断PBK信号通路后，PNU上调磷酸化Akt蛋白的作用被显著抑制（P〈0．01）；（3）在细胞裂解液及培养基中，PNU显著增强星形胶质细胞对Aβ聚集的抑制作用（P〈0．01）；使用LY294002阻断PBK信号通路后，PNU增强星形胶质细胞抑制Aβ聚集的功能显著减弱（P〈0．01）。结论PNU通过激活星形胶质细胞a7nAChRs上调内源性Cryab从而抑制Aβ集聚；PBK／Akt信号通路可能参与PNU激活星形胶质细胞a7nAChRs上调内源性Cryab蛋白抑制Aβ集聚的过程。Objective To investigate the possible mechanism of PNU on amyloid β （Aβ） aggregation via activation a7 nAChRs as well as upregulation endogenous Cryab. Methods Primary culture astrocytes were separated from neonatal SD rat cerebral cortex;Aβ1-42 oli- gomers were prepared in vitro. Astrocytes were divided into control, PNU, MLA, Aβ1-42, PNU ＋ Aβ1-42, PNU ＋ LY294002 ＋ Aβ1-42 groups. The protein levels of Cryab, phosphorylated-Akt （ ser473 ） and A[3 oligomers in the ceils were detected by Western blot. Results （ 1 ） PNU significantly increased endogenous Cryab in astrocytes（P〈0.05）. The effect of upregulation endogenous Cryab by PNU was significantly in- hibited by a7 nAChR antagonist-MLA （P〈0.05）. After PI3K signaling pathway was blocked by LY294002, the effect of upregulation endoge- nous Cryab by PNU was significantly inhibited（P〈0.01 ）. （2）PNU significantly increased phosphorylated-Akt in astrocytes （P〈0.05）. The effect of up regulation phosphorylated-Akt by PNU was significantly inhibited by a7 nAChR antagonist-MLA（P〈0. 01 ）. After PI3K signaling pathway was blocked by LY294002, the effect of upregulati0n phosphorylated-Akt by PNU was significantly inhibited （P〈0.01）. （3） In cell lysis solution and medium, PNU significantly enhanced astrocyte to inhibit Aβ aggregation （ P〈0.01 ）. After PI3K signaling pathway was blocked by LY294002, the effect of inhibition AI3 aggregation by PNU was significantly inhibited （P〈0.01）. Conclusions PNU could signif- icantly inhibit Aβ aggregation via activated a7 nAChRs as well as upregulation endogenous Cryab in astrocytes. PI3K/Akt signaling pathway is likely to be invoved in this process.

关 键 词：星形胶质细胞 阿尔茨海默病 a7胆碱能受体 PNU B-晶状体蛋白 β 淀粉样蛋白 

分 类 号：R34[医药卫生—基础医学]