5脂氧合酶激活蛋白介导人脐静脉内皮细胞氧化损伤

目的探讨5脂氧合酶激活蛋白在人脐静脉内皮细胞氧化损伤中的机制。方法体外分离、培养人脐静脉内皮细胞,分别用10、50、100和200mg/L氧化型低密度脂蛋白处理细胞24h,采用酶联免疫吸附法检测细胞上清液白三烯C4水平,MTT法检测细胞活力,以及实时荧光定量PCR和Western blot检测细胞5脂氧合酶激活蛋白mRNA及蛋白表达的变化。结果100mg/L和200mg/L氧化型低密度脂蛋白作用人脐静脉内皮细胞24h细胞活力显著下降(P<0.01),白三烯C4分泌显著增加(P<0.01),回归分析显示白三烯C4释放量与氧化型低密度脂蛋白浓度显著相关(r=0.953,P<0.01)。PCR和Western blot分析发现,5脂氧合酶激活蛋白mRNA表达和蛋白表达均显著增强(P<0.01和P<0.05)。结论氧化型低密度脂蛋白促进人脐静脉内皮细胞分泌白三烯C4,导致人脐静脉内皮细胞氧化损伤可能与5脂氧合酶激活蛋白异常表达有关。

Five Lipoxygenase Activating Protein-Mediated Human Umbilical Vein Endothelial Cells Oxidation Injury Induced by Oxidized Low Density Lipoprotein

Aim To investigate whether five lipoxygenase activating protein(FLAP) is involved in the mechanism of human umbilical vein endothelial cells(hUVEC) oxidation injury induced by oxidized low density lipoprotein(ox-LDL). Methods Isolated and cultured hUVEC were used as experimental model.hUVEC were induced by ox-LDL at 10,50,100 and 200 mg/L for 24 hours.Leukotriene C4(LTC4) levels in the cell supernatant fluid were detected with enzyme-linked immunosorbent assay(ELISA),cell viability was detected by MTT assay,and FLAP mRNA and FLAP protein were detected with fluorescent quantitation PCR and Western blot. Results Ox-LDL at 100 and 200 mg/L significantly induced the release of LTC4(P<0.01),the decrease of cell viability in hUVEC(P<0.01) and upregulation of FLAP mRNA expression and FLAP protein expression.The regressive analysis showed that the amounts of released LTC4 had significantly positive correlation with the concentration of ox-LDL(r=0.953,P<0.01). Conclusion FLAP could be involved in the LTC4 secretion and oxidative injury induced by ox-LDL in hUVEC.