Schmidt A M, Hasu M, Popov D, Zhang J H, Chen J, Yan S D, Brett J, Cao R, Kuwabara K, Costache G
Department of Medicine, Columbia University, College of Physicians and Surgeons, New York, NY 10032.
Proc Natl Acad Sci U S A. 1994 Sep 13;91(19):8807-11. doi: 10.1073/pnas.91.19.8807.
The extended interaction of aldoses with proteins or lipids results in nonenzymatic glycation and oxidation, ultimately forming AGEs, the presence of which in the plasma and vessel wall is associated with diabetic vascular complications. We show here that AGE albumin in the intravascular space interacts with the vessel wall via binding to an integral membrane protein, receptor for AGE (RAGE), a member of the immunoglobulin superfamily, resulting in clearance from the plasma and induction of interleukin 6 mRNA. Intravenously infused 125I-AGE albumin showed a rapid phase of plasma clearance with deposition in several organs. Rapid removal of 125I-AGE albumin from the plasma was prevented by administration of a soluble, truncated form of RAGE, which blocked binding of 125I-labeled AGE albumin to cultured endothelial cells and mononuclear phagocytes, as well as by pretreatment with anti-RAGE IgG. Ultrastructural studies with AGE albumin-colloidal gold conjugates perfused in situ showed that in murine coronary vasculature this probe was taken up by endothelial plasmalemmal vesicles followed by transport either to the abluminal surface or by accumulation in intracellular vesicular structures reminiscent of endosomes and lysosomes. Consequences of AGE-RAGE interaction included induction of interleukin 6 mRNA expression in mice. These data indicate that RAGE mediates the interaction of AGEs with the vessel wall, both for removal of these glycated proteins from the plasma and for changes in gene expression.
醛糖与蛋白质或脂质的长期相互作用会导致非酶糖基化和氧化,最终形成晚期糖基化终末产物(AGEs),血浆和血管壁中AGEs的存在与糖尿病血管并发症相关。我们在此表明,血管内空间中的AGE白蛋白通过与一种整合膜蛋白——AGE受体(RAGE,免疫球蛋白超家族的一员)结合,与血管壁相互作用,从而导致其从血浆中清除并诱导白细胞介素6 mRNA的产生。静脉注射的125I-AGE白蛋白呈现出快速的血浆清除阶段,并在多个器官中沉积。给予可溶性截短形式的RAGE可阻止125I-AGE白蛋白从血浆中快速清除,这种截短形式的RAGE可阻断125I标记的AGE白蛋白与培养的内皮细胞和单核吞噬细胞的结合,抗RAGE IgG预处理也有同样效果。对原位灌注的AGE白蛋白-胶体金缀合物进行的超微结构研究表明,在小鼠冠状动脉血管系统中,该探针被内皮细胞质膜小泡摄取,随后转运至腔外表面,或积聚在类似于内体和溶酶体的细胞内囊泡结构中。AGE-RAGE相互作用的后果包括诱导小鼠白细胞介素6 mRNA表达。这些数据表明,RAGE介导了AGEs与血管壁的相互作用,既参与了从血浆中清除这些糖基化蛋白,也参与了基因表达的变化。