【摘要】 目的 :研究AngII对人单核 /巨噬细胞 (THP - 1细胞 )凝集素样氧化低密度脂蛋白受体 (LOX - 1 )蛋白表达和基因转录的影响 ,从细胞蛋白、分子水平探讨AngII和巨噬细胞LOX - 1相互之间的关系 ,以进一步了解两者在动脉粥样硬化中的地位。方法 :将不同浓度AngII(1× 1 0 - 9- 1× 1 0 - 5mol/L)与经 0 1 μmol/L佛波酯 (PMA)诱导分化后的THP - 1细胞共孵育 2 4h ,以及将 1× 1 0 - 6 mol/L浓度的AngII与诱导分化后的THP - 1细胞作用不同时间0、3、6、1 2、2 4、48h后 ,用细胞酶联免疫法和半定量RT -PCR分别检测LOX - 1蛋白和mRNA表达的情况。结果 :未经诱导的THP - 1细胞不表达LOX - 1mRNA ;而经PMA诱导后 ,THP - 1细胞停止增殖 ,由单核细胞分化成为巨噬细胞 ,并表达LOX - 1mRNA。不同浓度的AngII作用诱导分化后的THP - 1细胞 2 4h,细胞LOX - 1蛋白和mRNA的表达呈浓度依赖性显著增加。同一浓度的AngII作用THP - 1细胞 ,可呈时间依赖性诱导LOX - 1蛋白和mRNA表达 ,其趋势是 3h左右开始增加 ,2 4h左右至最高峰 ,之后逐渐减低。结论 :经PMA诱导分化后的THP - 1细胞表达LOX- 1 ;AngII能明显增强分化后的THP - 1细胞表达LOX - 1蛋白和mRNA ,并呈浓度和时间依赖性。AngII这种作用可能是促进动脉粥样硬化发生、发?更多还原

【Abstract】 AIM: Cross talk between oxidized low-density lipoprotein (ox-LDL) and angiotensin II(Ang-Ⅱ) may play an important role in the pathogenesis of atherosclerosis. In this study, we tested the hypothesis that AngⅡ can induce expression of lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1), a new receptor for ox-LDL, in cultured THP-1 cells. METHODS: Cultured THP-1 cells were treated with 0.1 μmol/L PMA for 48 hours at first .Then the cells were incubated with 10 -9 -10 -5 mol/L Ang II for 24 hours, or with 10 -6 mol/L Ang II for various time up to 48 hours. LOX-1 protein expression was examined by cell enzyme linked immunosorbent assay (ELISA), and LOX-1 mRNA was detected by quantitative competitive reverse transcription-polymerase chain reaction (RT-PCR) . RESULTS: PMA-untreated THP-1 cells didn’t express LOX-1 mRNA. After 48 h of PMA treatment, THP-1 cells differentiated and LOX-1 mRNA was detected. Incubation of AngII with THP-1 cells for 24 h significantly increased LOX-1 mRNA and protein expression in a concentration-dependent manner (10 -9 -10 -5 mol/L, P<0.05 ). Otherwise , after treatment with 1×10 -6 mol/L Ang II for 3 hours, LOX-1 protein and mRNA expression were elevated ( P <0.05), reaching the maximum at 24 hours, then it declined. CONCLUSIONS: PMA induces differentiation and LOX-1 mRNA expression in THP-1 cells. Ang II upregulates LOX-1 expression in a concentration-dependent and time-dependent manner, and this effect of Ang II may contribute to the pathogenesis of atherosclerosis.更多还原