摘要
目的探讨Rab4对氧化型低密度脂蛋白诱导的人脐静脉内皮细胞自噬的影响及其作用机制。方法不同浓度氧化型低密度脂蛋白孵育人脐静脉内皮细胞24 h,Western blot检测Beclin-1、微管相关蛋白1轻链3(LC3)表达,逆转录-聚合酶链反应及Western blot检测Rab4 mRNA及蛋白表达。75 mg/L氧化型低密度脂蛋白孵育Rab4基因转染人脐静脉内皮细胞(siRNA或Rab4质粒转染)24 h,Western blot检测Rab4、Beclin-1、LC3蛋白的表达。结果氧化型低密度脂蛋白孵育人脐静脉内皮细胞24 h后,Beclin-1蛋白表达以及LC3Ⅱ/LC3Ⅰ比值明显增加,而Rab4 mRNA以及蛋白的表达明显降低(P<0.05),并呈浓度依赖性。Rab4 siRNA进一步增加氧化型低密度脂蛋白诱导的Beclin-1蛋白表达量以及LC3Ⅱ/LC3Ⅰ比值(P<0.05),而Rab4质粒转染则下调氧化型低密度脂蛋白诱导的Beclin-1蛋白表达以及LC3Ⅱ/LC3Ⅰ比值增加(P<0.05)。结论氧化型低密度脂蛋白通过下调Rab4表达诱导血管内皮细胞自噬。
Aim To explore the effect of oxidized low density lipoprotein （ox-LDL） on human vascular umbilical vein endothelial cell （HUVEC） autophagy and its mechanism. Methods After treatment with ox-LDL for 24 h, Western blot was used to detect the protein expression of Beclin-1 and microtubule-associated protein 1 light chain 3 （ LC3 ） ; Reverse transcription polymerase chain reaction （RT-PCR） and Western blot were used to detect Rab4 mRNA and protein expression. After transfection with Rab4 siRNA and Rab4 plasmid, Western blot was used to measure the protein levels of Rab4, Beclin-1 and LC3 induced by 75 mg/L ox-LDL. Results After treatment with ox-LDL for 24 h, the protein expression of Beclin-1 and the ratio of LC3 II/LC3 I were increased. The levels of Rab4 mRNA and protein were obviously decreased with a concentration-dependent manner. When transfection with Rab4 siRNA, the protein level of Beclin-1 and the ratio of LC3 II/LC3 I induced by ox-LDL were further increased. When transfection with Rab4 plasmid, the increased protein level of Beclin-1 and the ratio of LC3 II/LC3 I induced by ox-LDL were attenuated. Conclusion ox-LDL increased HUVEC autophagy via down-regulation of Rab4 expression.
出处
《中国动脉硬化杂志》
CAS
CSCD
北大核心
2013年第6期518-522,共5页
Chinese Journal of Arteriosclerosis
