N核因子-κB活化参与Ox-LDL诱导人肾小球系膜细胞表达单核细胞趋化蛋白-1(英文)

Nuclear factor-κB activation is involved in MCP-1 expression in human mesangial cells 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<0.01vscontrol;P<0.05vs10,25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<0.01vscontrol;P<0.05vs30min or240min)。以50mg/L Ox-LDL刺激MCs1h后,细胞内IκBα蛋白水平最低(0.050±0.006,n=5,P<0.01vscontrol),作用24h MCP-1表达水平最高(0.331±0.016,n=5,P<0.01vscontrol)。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。

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 〈 0.01 vs control; P 〈 0.05 vs 10, 25 and 100mg/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 or240 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 in- hibitor pyrroledithiocarbomate （PI）TC） could inhibit these effects induced by Ox - LDL. CONCLUSION： Activation of NF- κB regulate the expression of MCP - 1 in HMCs induced by Ox - LDL.