血凝素样氧化低密度脂蛋白对单核巨噬细胞源泡沫细胞基质金属蛋白酶-9的调控作用

Effects of lectin-like oxidized low density lipoprotein on MMP-9 in human monocyte-macrophage-derived foam cells

目的观察氧化低密度脂蛋白(ox-LDL)对人单核巨噬细胞源泡沫细胞分泌的基质金属蛋白酶-9(MMP-9)的表达和活性的影响,以及此过程中血凝素样氧化低密度脂蛋白受体-1(LOX-1)的调控作用。方法体外原代培养人单核细胞来源的巨噬细胞,传至2～6代用于实验。依不同浓度ox-LDL(20、40、80mg/L)作用24h,以及ox-LDL40mg/L作用1、12、24h分组,另设LOX-1受体阻断剂多聚肌苷酸(PolyI)干预组。反转录-聚合酶链反应(RT-PCR)测定LOX-1和MMP-9mRNA表达,酶谱法分析MMP-9的活性。结果 ox-LDL作用后,LOX-1和MMP-9mRNA表达升高,MMP-9的分泌及活性升高(P<0.05),且诱导作用呈浓度-时间依赖性;多聚肌苷酸抑制后,MMP-9mRNA表达及活性明显下降(P<0.05)。结论 LOX-1作为ox-LDL的特异性受体,介导ox-LDL诱导的上调单核巨噬细胞LOX-1、MMP-9表达及活性的作用。

Objective To investigate how ox-LDL affects expression and activity of MMP-9 secreted by human monocyte-macrophage-derived foam cells and role of LOX-1 in this procedure. Methods The second to sixth passages of human monocyte-derived macrophages cultured in vitro were used in this experiment. The macrophages were allocated to several groups depending on incubation with 20, 40 or 80 mg/ L ox-LDL for 24 hours, or 40 mg/ L ox-LDL for 1, 12 or 24h. In addition, an intervention group was set where macrophages were incubated with polyinosinic acid （Poly I）, a LOX-1 blocker. The expressions of MMP-9 mRNA and Lox-1 mRNA were determined with RT-PCR, and the activity of MMP-9 by zymography. Results Expressions of LOX-1 and MMP-9 mRNA and secretion and activity of MMP-9 were increased by ox-LDL in a concentration-and time-dependent manner （P〈0.05）; Inhibition with polyinosinic acid was clearly associated with a decline in, expressions and activity of MMP-9 mRNA （P〈0.05）. Conclusion LOX-1 as a specific receptor of ox-LDL may be responsible for ox-LDL mediated up-regulation of LOX-1 and MMP-9 expressions and activity in monocyte/macrophages.