脂肪酸结合蛋白4诱导氧化低密度脂蛋白促进胆固醇在血管平滑肌细胞中沉积作用研究  

Fatty Acid Binding Protein 4 Induces Oxidized Low Density Lipoprotein to Promote Cholesterol Deposition in Vascular Smooth Muscle Cells

作　　者：侯苗苗 李桂忠 HOU Miaomiao;LI Guizhong(Ningxia Medical University,Yinchuan 750004;Department of Pathophysiology,Basic Medical School,Ningxia Medical University,Yinchuan 750004;Ningxia Key Laboratory of Vascular Injury and Repair Research,Yinchuan 750004)

机构地区：[1]宁夏医科大学,银川750004 [2]宁夏医科大学基础医学院病理生理学系,银川750004 [3]宁夏血管损伤与修复研究重点实验室,银川750004

出　　处：《宁夏医科大学学报》2018年第7期776-780,共5页Journal of Ningxia Medical University

基　　金：国家自然科学基金(81360059);西部一流学科建设项目

摘　　要：目的探讨转录因子FABP4在氧化低密度脂蛋白(ox-LDL)致血管平滑肌细胞(VSMCs)胆固醇沉积中的作用和机制。方法体外培养血管平滑肌细胞,分为4组:0μg·mL^(-1) ox-LDL组、50μg·mL^(-1) ox-LDL组、100μg·mL^(-1)ox-LDL组和50μg·mL^(-1) ox-LDL+脂肪酸结合蛋白4(FABP4)过表达病毒组(成功感染FABP4过表达病毒至平滑肌细胞细胞后,再给予50μg·mL^(-1) ox-LDL刺激)。各组ox-LDL刺激细胞时间为48h。刺激培养结束后收集各组细胞,用油红O染色验证脂质沉积模型复制是否成功,过氧化物酶法检测甘油三酯(TG)、总胆固醇(TC)含量的变化,qRT-PCR检测平滑肌细胞中FABP4 mRNA的表达,Western blot检测平滑肌细胞中FABP4蛋白的表达情况。结果 ox-LDL刺激细胞48h后,油红O染色显示平滑肌细胞质内充满了大量红染脂质颗粒,胞核呈蓝色,且50μg·mL^(-1) ox-LDL处理后细胞内TG、TC含量升高(P<0.05);qRT-PCR和Western blot结果显示,50μg·mL^(-1)ox-LDL干预平滑肌细胞后FABP4 mRNA与蛋白表达水平均上调(P<0.01)。转染FABP4过表达病毒至平滑肌细胞后,可见细胞中FABP4的表达水平升高(P<0.01),油红O染色显示平滑肌细胞质内红染脂质颗粒较单纯给予50μg·mL^(-1) ox-LDL组增多,细胞内TG、TC含量也升高(P<0.05)。结论 FABP4表达水平上调可能是ox-LDL致平滑肌细胞胆固醇沉积的机制之一。Objective To investigate th e role and mechanism of transcription factor FABP4 in cholesterol accumulation in vascular smooth muscle cells（VSMCs）induced by oxidized low density lipoprotein（ox-LDL）.Methods VSMCs were cultured in vitro and divided into four groups： 0 μg·mL^-1 ox-LDL group,50μg·mL^-1 ox-LDL group,100 μg·mL^-1 ox-LDL group,and 50 μg·mL^-1 ox-LDL＋ FABP4 overexpression virus group.Ox-LDL stimulated time in each group was 48 h. After the stimulation,the cells were collected,and oil red O staining was used to verify the success of lipid deposition model replication. The changes of total cholesterol（TG）and triglyceride（TC）contents were detected by peroxidase method,the expression of FABP4 m RNA in smooth muscle cells was detected by qRT-PCR,and the expression of FABP4 protein in smooth muscle cells was detected by Western blot. Results After 48 hours of ox-LDL stimulation,the cytoplasm was filled with a large number of red-stained lipid granules and the nucleus was blue,and the contents of TG and TC were increased after 50 μg·mL^-1 ox-LDL treatment（P0.05）;the results of qRT-PCR and Western blot showed that FABP4 m RNA and TC were increased after 50 μg·mL^-1 ox-LDL treatment. The level of protein expression was upregulated（P0.01）. After transfection of FABP4 overexpression virus into smooth muscle cells,the expression of FABP4 increased（P0.01）. Oil red O staining showed that the expression of red stained lipid granules in smooth muscle cells was higher than that in the 50μg·mL^-1 ox-LDL group,and the cholesterol content was also increased（P0.05）. Conclusion Up-regulation of FABP4 expression may be one of the mechanisms of cholesterol accumulation in ox-LDL-induced smooth muscle cells.

关 键 词：脂肪酸结合蛋白4 氧化低密度脂蛋白 血管平滑肌细胞 胆固醇沉积 

分 类 号：R543.1[医药卫生—心血管疾病]