【摘要】 目的 探讨大黄酸对转化生长因子β1(TGF-β1)诱导人脐静脉内皮细胞纤溶酶原激活物抑制物1(PAI-1)mRNA表达和蛋白合成的影响,以阐明大黄酸对内皮细胞的保护作用。方法 以人脐静脉细胞系ECV-304为研究对象,Northern blot检测PAI-1 mRNA的表达,流式细胞仪法检测PAI-1蛋白的合成,免疫沉淀法和Western blot检测p44/p42丝裂原活化蛋白激酶(MAPK)活性。结果 大黄酸可以快速抑制TGF-β1诱导的内皮细胞PAI-1 mRNA的表达,且呈明显的剂量依赖效应,如果作用时间延长,则对蛋白的合成同样具有明显抑制作用。进一步的研究还发现,大黄酸对TGF-β1激活的p44/p42 MAPK活性具有明显下调作用。结论 大黄酸对TGF-β1诱导的PAI-1高表达的抑制作用可能是其保护内皮细胞功能从而防治糖尿病及其血管并发症的作用机制之一。更多还原

【Abstract】 Objective To investigate the effect of rhein on endothelial plasminogen activator inhibitor-1 (PAI-1) mRNA expression and protein synthesis induced by transforming growth factor β1 (TGF-β1), and explore the protective mechanism of rhein on human endothelial cells. Methods A human umbilical endothelium derived cell line (ECV-304) from ATCC was used in this study. The endothelial PAI-1 mRNA expression and protein synthesis were detected by Northern blot and flowcytometry analysis respectively. The activity of phospho-p44/p42 MAPK induced by TGF-β1 was determined by immunoprecipitation analysis and Western blot. Results TGF-β1 (2μg/L) could increase rapidly endothelial PAI-1 mRNA expression and persist for 24 hours. The PAI-1 mRNA expression induced by TGF-β1 in endothelial cells was inhibited by incubating with rhein. Rhein could also inhibit the endothelial PAI-1 protein synthesis. Further study revealed rhein showed a significantly inhibitory effect on the activity of phospho-p44/p42 MAPK induced by TGF-β1 in human endothelial cells. Conclusions Rhein shows a protective action on endothelial cells by inhibiting PAI-1 overexpression, and this may provide beneficial effects on the treatment of diabetes mellitus and its complications.更多还原