氧化型低密度脂蛋白对人脐静脉内皮细胞增殖及IL18分泌的影响

目的探讨氧化型低密度脂蛋白（ox-LDL）对人脐静脉内皮细胞（HUVECs）增殖及白介素18（IL18）分泌的影响，以阐明其在动脉粥样硬化发生中的作用。方法体外培养人脐静脉内皮细胞株，3～6代用于实验。实验分空白对照组和不同浓度ox-LDL组。将不同浓度的ox-LDL（10、20、50、100、200mg／L）与内皮细胞共同孵育12、24、36、48h。采用细胞酶联免疫吸附分析（ELISA）检测培养上清液中IL18含量；采用四唑盐比色法检测各孔的吸光值（0D），以评价增殖效果。结果10mg／L ox-LDL促进内皮细胞增殖，20～200mg／Lox-LDL呈剂量依赖性抑制内皮细胞增殖（P〈0．05，P〈0.01）。正常内皮细胞不分泌IL18。ox-LDL诱导HUVECs分泌IL18，呈浓度依赖性，100mg／L浓度时IL18分泌达高峰。ox-LDL诱导HUVECs分泌IL18亦呈时间依赖性，与12h比较，24、36、48h均有统计学意义（P〈0.05，P〈0.01）。结论ox-LDL诱导HUVECs分泌IL18，抑制HUVECs增殖，这可能与ox-LDL致动脉粥样硬化作用机制有关。

Effect of Oxidized Low Density Lipoprotein on the Production of Interleukin-18 in and the Proliferation of Cultured Human Umbilical Vein Endothelial Cells

Objective To investigate the effects of oxidized low density lipoprotein(ox-LDL) on the production of interleukin-18(IL18) and the proliferation in cultured human umbilical vein endothelial cells(HUVECs).Methods Cultured HUVECs at passage 3 to 6 were used for experiment.There were control group and ox-LDL groups with different concentration.HUVECs were incubated with different concentration(10,20,50,100,200 mg/L) of ox-LDL for different periods(12,24,36,48h).IL18 in supernatant medium was detected by cell ELISA and cell proliferation was measured by MTT colorimetric assay.Results Ox-LDL(10 mg/L) could enhance the proliferation of HUVECs,but ox-LDL(20~200 mg/L) could inhibit it in a dose-dependent manner(P<0.05,P<0.01).HUVECs didn't release IL18 without stimulation.The production of IL18 activated by Ox-LDL in HUVECs remarkably increased in a dose-dependent manner.Maximal levels of IL18 occurred at 100mg/L of LDL.The enhancing effect was also time-dependent.Compared with 12h,the levels of IL18 were significantly increased at 24,36,48 h of stimulation with Ox-LDL(P<0.05,P<0.01).Conclusion ox-LDL could obviously stimulate the production of IL18 in HUVECs and inhibit the proliferation of HUVECs,which may thereby influence the pathogenesis of atherosclerosis.