AIM: To investigate the role of nuclear factor- κB (NF- κB) in the expression of monocyte chemoatractant protein- 1 (MCP- 1) in human mesangial cells (HMCs) induced by oxidized low- density lipoprotein (Ox- LDL).METHODS: HMCs were used as target cells. Inhibitory κBα (IκBα) and MCP- 1 protein level was measured by cell ELISA.Activities of transcriptional factors NF- κB were determined by electrophoresis mobility shift assay (EMSA). Immunohistochemistry was used to detect the translocation of Rel p65. RESULTS: NF - κB DNA - binding activation in MCs was observed when 10-100 mg/L Ox - LDL was added to the medium, and 50 mg/L Ox - LDL caused the strongest effect (8.50 ± 1.14, P ＜ 0.01vs control; P ＜ 0.05 vs 10, 25 and 100 mg/L Ox - LDL). The most optimal stimulation time was 60 min ( 11.0 ± 2.11, P ＜0.01 vs control; P ＜ 0.05 vs 30 min or 240 min). IκBα protein level in MC dropped down most obviously after 60 min incubation with 50 mg/L Ox - LDL (0.050 ± 0.006, n = 5, P ＜ 0.01 vs control), while MCP- 1 expression level was the highest (0.331± 0.016, n = 5, P ＜ 0.01 vs control). The translocation of Rel p65 from cytoplasm to nucleus was detected too. NF - κB inhibitor pyrroledithiocarbomate (PDTC) could inhibit these effects induced by Ox- DL. CONCLUSION: Activation of NF- κB regulate the expression of MCP- 1 in HMCs induced by Ox - LDL.%目的:研究核因子-κB(NF-κB)在氧化低密度脂蛋白(Ox-LDL)诱导的体外培养的人肾小球系膜细胞表达单核/巨噬细胞趋化蛋白-1(MCP-1)中的作用.方法:采用凝胶迁移率变动分析检测NF-κB的DNA结合活性变化,以免疫组化观测细胞内REL P65的核转位,用细胞ELISA法检测细胞内MCP-1及IκBα蛋白含量变化.结果:不同浓度(10、25、50、100mg/L)Ox-LDL刺激肾小球系膜细胞均可引起细胞NF-κB的DNA结合活性增强,50mg/L Ox-LDL活化MCs效果最明显(8.50±1.14,P＜0.01 vs control;P＜0.05 vs 10,25和100mg/L Ox-LDL).Ox-LDL刺激MCs30-240min均可以活化NF-κB,60min时相点活性最强(11.0±2.11,P＜0.01 vs control;P＜0.05 vs30 min or 240 min).以50 mg/L Ox-LDL刺激MCs 1 h后,细胞内IκBα蛋白水平最低(0.050±0.006,n=5,P＜0.01 vscontrol),作用24h MCP-1表达水平最高(0.331±0.016,n=5,P＜0.01 vs control).NF-κB活化的同时伴有RELP65核转位.上述效应可被NF-κB特异性抑制剂吡咯二硫氨基甲酸酯(PDTC)所抑制.结论:Ox-LDL刺激人肾小球系膜细胞产生MCP-1是由NF-κB调控,NF-κB参与了脂质肾损害的发病过程.
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