血管平滑肌细胞自噬对小鼠主动脉夹层形成的影响

Impact of Autophagy in Vascular Smooth Muscle Cells on Mouse Aortic Dissection

【目的】研究血管平滑肌自噬对小鼠主动脉夹层形成的影响。【方法】①构建小鼠主动脉夹层模型:60只C57BL/6小鼠被随机分为三组:阴性对照组、实验(AD)组、氯喹(CQ)干预组,实验组与CQ组使用β-氨基丙腈(BAPN)喂养联合人血管紧张素-Ⅱ(Ang-Ⅱ)皮下注射16 d构建小鼠主动脉夹层的模型,同时干预组每天腹腔注射CQ,对照组给予生理盐水。②Yes相关蛋白(YAP)、自噬相关蛋白及血管平滑肌细胞相关标志蛋白的检测:采用蛋白质免疫印迹法、免疫组织化学染色法对小鼠主动脉样本中YAP、微管相关蛋白1轻链3(LC3)、P62及血管平滑肌细胞不同表型相关标志蛋白进行检测。【结果】①实验组主动脉夹层的发生率为60%,干预组小鼠未见明显主动脉夹层形成征象。②与对照组相比,实验组与干预组小鼠主动脉中合成型血管平滑肌细胞(VSMC)标志蛋白骨桥蛋白(OPN)、LC3含量明显增高,同时,收缩型VSMC标志蛋白α-SMA及YAP蛋白的表达下降(P<0.05)。【结论】在BAPN联合Ang-Ⅱ构建的小鼠主动脉夹层模型中,YAP蛋白调控VSMC表型转化,且该过程受到自噬的调节,自噬可能作为YAP蛋白调控VSMC表型转化致小鼠主动脉夹层形成的关键。

【Objective】To identify the role of autophagy in vascular smooth muscle cells(VSMC)and the formation of aortic dissection(AD)using a murine model.【Methods】①Sixty C57BL/6 mice were randomly divided into three groups:control group,model group and chloroquine(CQ)group.The model and CQ groups were fedβ-aminopropionitrile(BAPN)and injected with human angiotensin-Ⅱ(Ang-Ⅱ)for 16 days.The CQ group had chloroquine injected into the abdominal cavity of the mice daily while the control group was injected with normal saline using the same method.②YAP,LC3,p62 and different phenotype related marker proteins were measured by western blot and immunohistochemistry stain⁃ing.【Results】①The incidence of AD was 60%in the model group,while there was no case found in the CQ group.②LC3 and synthetic related marker proteins of VSMC were significantly and highly expressed in the model and CQ groups,whereas the expression of VSMC contractile phenotype proteins and YAP inversely decreased(P<0.05).【Conclusion】Results demonstrate that autophagy regulates the phenotypic transformation of VSMC via YAP protein pathways.