氧化型低密度脂蛋白对RAW264.7细胞Siglec-1表达及分泌细胞因子的影响

目的 通过氧化型低密度脂蛋白(oxidized low-density lipopretein,ox-LDL)活化巨噬细胞系对Siglec-1(sialic acid-binding immunoglobuhn-like herin 1,唾液酸黏附素)表达及细胞因子分泌的影响探讨对动脉粥样硬化(atherosclerosis,AS)发病的可能作用.方法 制备ox-LDL,并用不同浓度ox-LDL刺激小鼠巨噬细胞株RAW264.7,48 h后收集细胞和上清,分别用流式细胞仪和RT-PCR检测不同浓度ox-LDL刺激后细胞表面Siglec-1蛋白和基因表达水平,并测定培养上清液中巨噬细胞炎性蛋白-1α(MIP-1α)、单核细胞趋化蛋白-1(MCP-1)和IL-8的浓度.结果 与对照组相比,ox-LDL能刺激RAW264.7细胞表面Siglec-1蛋白和mRNA表达升高(P<0.01),培养上清液中MIP-1α、MCP-1和IL-8的表达升高(P<0.01),并呈浓度依赖性.结论 ox-LDL可呈剂量依赖性刺激RAW264.7巨噬细胞诱导Siglec-1表达及分泌炎性细胞因子增加,在动脉粥样硬化的发生发展中可能起一定作用.

Increased expression of Siglec-1 and cytokines by stimulation of oxidized low-density lipoprotein on RAW264.7 cells

Objective To explore the role of sialic acid-binding immunoglobulin-like lectin-one (Siglec-1) in the process of atherosclerotic inflammation induced by oxidized low-density hpepmtein (ox-LDL). Methods Ox-LDL was synthesized by oxidization of native LDL and different concentration of ox-LDL was added to the culture medium of RAW264.7. Forty-eight hours later, cells and supernatants were collected separately. The expression of Siglec-1 protein and mRNA were measured by flow cytometry(FCM) and real-time quantitative RT-PCR, respectively. The levels of monocyte chemotactic protein-1 (MCP-1), macrophage inflammatory protein-1α(MIP-1α) and IL-8 in supernatants were determined by ELISA. Re-sults By the stimulation of ox-LDL, Siglec-1 protein and mRNA on RAW264.7 cells were significantly in-creased, meanwhile, the cytokines levels in culture supematants were significantly higher than that in the control group. And both Siglec-1 expression and cytokine secretion were ox-LDL dose-dependent. Conclu-sion Ox-LDL can increase Siglec-1 protein and mRNA expression and some inflammatory cytokines secre-tion on RAW264.7 cells in a dose-dependent manner. Manifested by enhanced Siglec-1 expression, the acti-vated macmphages may take a part in the development and progression of atherosclerosis.