糖化白蛋白对人脐静脉内皮细胞MCP-1表达的影响及其机制研究

Effects of glycated serum albumin on expression of MCP-1 in cultured human umbilical vein endothelial cells

目的:探讨糖化白蛋白对内皮细胞中单核细胞趋化蛋白-1(MCP-1)表达的影响及其机制。方法:将人脐静脉内皮细胞(HUVECs)与不同浓度的糖化白蛋白共同培养,并用糖基化产物抑制剂氨基胍(AG)和抗氧化剂N-乙酰半胱氨酸(NAC)干预。分别用免疫细胞化学和夹心ELISA方法测定细胞MCP-1的表达,硫代巴比妥酸法和黄嘌呤氧化酶法测定细胞内丙二醛含量和超氧化物歧化酶活性。结果:糖化白蛋白促进HUVECs合成和分泌MCP-1。免疫细胞化学显示,HUVECs暴露于50mg/L糖化白蛋白后,随作用时间的延长(4 h、8 h、12h),MCP-1的表达增高(P<0.01),分别为对照组的1.3、1.9和2.8倍(P<0.01);糖化白蛋白能引起细胞内超氧化物歧化酶活性下降(P<0.05)和丙二醛含量升高(P<0.01)。氨基胍和N-乙酰半胱氨酸能抑制糖化白蛋白刺激内皮细胞表达MCP-1(P<0.01),N-乙酰半胱氨酸能抑制糖化白蛋白对内皮细胞内超氧化物歧化酶和丙二醛的影响(P<0.05)。结论:糖化白蛋白可刺激人类内皮细胞表达MCP-1,糖化白蛋白刺激MCP-1表达与其诱导细胞内氧化应激有关。

AIM：To investigate the effects of glycated serum albumin（GSA） on the expression of monocyte chemoattratant protein-1（MCP-1） in endothelial cells.METHODS： Human umbilical vein endothelial cells（HUVECs） were cultured with GSA at different concentrations in the presence or absence of glycosylation-product inhibitor aminoguanidine（AG） and anti-oxidant N-acetylcysteine（NAC）.The expression of MCP-1 was evaluated by the methods of immunocytochemistry and sandwich ELISA.Malondialdehyde（MDA） content and superoxide dismutase（SOD） activity were determined by the technique of thiobarbituric acid（TBA） and xanthine oxidase（XOD）,respectively.RESULTS： GSA stimulated HUVECs to produce and release MCP-1.After HUVECs were treated with 50 mg/L GSA,the expression of MCP-1 at 4 h,8 h and 12 h was 1.3,1.9 and 2.8 folds higher than that in control group（P0.01）,respectiuely.The significant difference among the experiment groups（P0.01） was observed,indicating that GSA took effect in a concentration-dependent manner.The release of MCP-1 in cultured supernatants in the experiment groups with 3 different concentrations of GSA was 1.6,2.4 and 3.0 folds as much as that in control group（P0.01）,and the significant difference among the experiment groups（P0.01） was also observed.GSA decreased the activity of SOD（P0.05） and increased the content of MDA（P0.01）.AG and NAC obviously inhibited the upregulation of MCP-1 expression in HUVECs by GSA（P0.01）.NAC also inhibited the effect of GSA on SOD activity and MDA content in HUVECs（P0.05）.CONCLUSION： GSA stimulates the expression of MCP-1 by inducing oxidative stress in endothelial cells.