Department of Medicine, Diabetes Research Center, Albert Einstein College of Medicine, Bronx, New York, USA.
Diabetes. 2010 Jan;59(1):249-55. doi: 10.2337/db09-0801. Epub 2009 Oct 15.
RAGE interacts with the endogenous ligands S100 calgranulins and high mobility group box 1 (HMGB1) to induce inflammation. Since hyperglycemia-induced reactive oxygen species (ROS) activate many pathways of diabetic tissue damage, the effect of these ROS on RAGE and RAGE ligand expression was evaluated.
Expression of RAGE, S100A8, S100A12, and HMGB1 was evaluated in human aortic endothelial cells (HAECs) incubated in normal glucose, high glucose, and high glucose after overexpression of either uncoupling protein 1 (UCP1), superoxide dismutase 2 (SOD2), or glyoxalase 1 (GLO1). Expression was also evaluated in normal glucose after knockdown of GLO1. Expression was next evaluated in high glucose after knockdown of nuclear factor (NF)-kappaB p65 (RAGE) and after knockdown of activated protein-1 (AP-1) (S100A8, S100A12, and HMGB1), and chromatin immunoprecipitation (ChIP) was performed +/- GLO1 overexpression for NFkappaB p65 (RAGE promoter) and AP-1 (S100A8, S100A12, and HMGB1 promoters). Finally, endothelial cells from nondiabetic mice, STZ diabetic mice, and STZ diabetic mice treated with the superoxide dismutase mimetic Mn(III)tetrakis(4-benzoic acid)porphyrin chloride (MnTBAP) were evaluated.
High glucose increased RAGE, S100A8, S100A12, and HMGB1 expression, which was normalized by overexpression of UCP1, SOD2, or GLO1. GLO1 knockdown mimicked the effect of high glucose, and in high glucose, overexpression of GLO1 normalized increased binding of NFkappaB p65 and AP-1. Diabetes increased RAGE, S100A8, and HMGB1 expression, and MnTBAP treatment normalized this.
These results show that hyperglycemia-induced ROS production increases expression of RAGE and RAGE ligands. This effect is mediated by ROS-induced methylglyoxal, the major substrate of glyoxalase 1.
晚期糖基化终末产物（ RAGE ）与内源性配体 S100 钙结合蛋白和高迁移率族蛋白 1 （ HMGB1 ）相互作用，诱导炎症反应。由于高血糖诱导的活性氧（ ROS ）激活了许多糖尿病组织损伤途径，因此评估了这些 ROS 对 RAGE 和 RAGE 配体表达的影响。
在正常葡萄糖、高葡萄糖以及过表达解偶联蛋白 1 （ UCP1 ）、超氧化物歧化酶 2 （ SOD2 ）或甘油醛 3-磷酸脱氢酶 1 （ GLO1 ）后的人主动脉内皮细胞（ HAEC ）中，评估 RAGE 、 S100A8 、 S100A12 和 HMGB1 的表达。在正常葡萄糖中敲低 GLO1 后，再次评估表达情况。在高葡萄糖中敲低核因子（ NF ） -κB p65 （ RAGE ）和激活蛋白-1 （ AP-1 ）（ S100A8 、 S100A12 和 HMGB1 ）后，评估表达情况，并进行染色质免疫沉淀（ ChIP ），分别评估 GLO1 过表达对 NFkappaB p65 （ RAGE 启动子）和 AP-1 （ S100A8 、 S100A12 和 HMGB1 启动子）的影响。最后，评估非糖尿病小鼠、链脲佐菌素（ STZ ）糖尿病小鼠和 STZ 糖尿病小鼠用超氧化物歧化酶模拟物 Mn(III)四（ 4- 苯甲酸）卟啉氯化物（ MnTBAP ）治疗后的内皮细胞。
高葡萄糖增加了 RAGE 、 S100A8 、 S100A12 和 HMGB1 的表达，而过表达 UCP1 、 SOD2 或 GLO1 则使其恢复正常。 GLO1 敲低模拟了高葡萄糖的作用，而在高葡萄糖中， GLO1 的过表达使 NFkappaB p65 和 AP-1 的结合增加恢复正常。糖尿病增加了 RAGE 、 S100A8 和 HMGB1 的表达， MnTBAP 治疗使这种情况恢复正常。
这些结果表明，高血糖诱导的 ROS 产生增加了 RAGE 和 RAGE 配体的表达。这种作用是由 ROS 诱导的甲基乙二醛介导的，甲基乙二醛是甘油醛 3-磷酸脱氢酶的主要底物。
