主动脉夹层小鼠血管壁中微管相关蛋白1轻链3、Beclin1及骨桥蛋白的表达及意义

摘要

目的 探讨主动脉夹层小鼠血管壁中微管相关蛋白1轻链3(Microtubule-associated protein 1 light chain 3,LC3)、Beclin1及骨桥蛋白(Osteopontin,OPN)的表达及意义.方法 (1)急性主动脉夹层模型的建立:3周龄FVB小鼠随机分为β-氨基丙腈(β-aminopropionitrilemonofumarate,BAPN)联合人血管紧张素-Ⅱ(Angiotensin-Ⅱ,Ang-Ⅱ)组,单BAPN干预组和对照组,分别予以BAPN口服4周后联合Ang-Ⅱ皮下微泵48 h,单用BAPN 4周口服和正常喂养进行干预.(2) LC3、Beclin1及OPN的检测:采用RT-PCR、免疫组织化学染色法对小鼠主动脉血管壁中自噬相关蛋白LC3、Beclin1及合成型血管平滑肌细胞(vascular smooth muscle cell,VSMC)标志蛋白OPN等进行定量和半定量测定.结果 (1)BAPN联合Ang-Ⅱ干预组小鼠夹层发生比例为86.7％,单BAPN组夹层发生比例低于联合组,对照组夹层发生比例为0;(2)急性主动脉夹层小鼠主动脉壁中自噬相关蛋白LC3B、Beclin1及合成型VSMC标志蛋白OPN基因和蛋白含量明显高于正常对照组(P＜0.05),且LC3B、Beclin1及OPN蛋白表达主要定位于血管中层VSMC.结论 BAPN联合Ang-Ⅱ能够成功诱导FVB小鼠发生急性主动脉夹层,且该模型中发生了VSMC表型转化和自噬现象,两者可能具有相关性.%Objective To explore the expression of microtubule-associated protein 1 light chain 3 、Beclin1 and osteopontinin aortic tissue of aortic dissection mice and to discuss the relevance.Methods (1) The establishment of aortic dissection model:3 weeks old FVB mice were randomly divided intoβ-aminopropionitrilemonofumarate (BAPN) with Angiotensin-Ⅱ (Ang-Ⅱ) group,BAPN only group and control group.The BAPN-Ang-Ⅱ group was intervened by BAPN orally at first 4 weeks and infused with Ang Ⅱ subcutaneously using a micro-osmotic pump for 48 h.The BAPN only group was intervened by BAPN orallyfor 4 weeks,and the control was given a placebo respectively.(2) Detecting the expression of microtubule-associated protein 1 light chain 3 、Beclin1 and osteopontin:RT-PCR and Immunohistochemistry staining was performed to detect the expression of LC3 B,Beclin1 and OPN in the aortic tissue of aortic dissectionmice.Results (1) the incidence of aortic dissection in the BAPN-Ang-Ⅱ is 86.7％ and the BAPN only group is lower than the collaborategroup.No aortic dissection was found in the control group.(2)It was identified that the autophagy related gene was much highly expressed in the AD mice's aortic tissue verse the normal one.According to immunohistochemistry staining,the autophagy related protein is mainly located in the medial vascular wall.Conclusion These data for the first time demonstrates that autophagy related gene and protein highly expressed in the AAD mouse's aortic tissue and it will provide us an available method and fundamental for the further studying in the influences of autophagy to AAD.