RAGE and the host response to hypoxic stress

外周动脉疾病是糖尿病的主要并发症，也是截肢的主要原因。 指手指或四肢。在过去的15年里，我的实验室一直专注于基因的分子调控。 低氧应激。在前一个周期中，三个主要发现将愤怒与急性反应的调节联系在一起 低氧：首先，在培养的内皮细胞和单核/巨噬细胞中，急性暴露于低氧 导致AGE反应性表位在低氧应激几分钟内迅速释放。第二，在完好无损的 在原代培养的小鼠主动脉和人血管内皮细胞中，RAGE调节 EGR-1被RAGE和AGE抑制剂氨基胍的缺失或敲除所抑制。 第三，在与项目1的合作中，我们表明单核/巨噬细胞没有RAGE或 RAGE细胞质结构域结合伙伴Diaphanous-1或MDIA-1在急性白血病中不上调Egr-1 缺氧。为了解决这些发现与糖尿病相关的影响，我们采用了一种体内模型 单侧股动脉结扎所致后肢缺血。糖尿病严重损害血管修复 这一模型中的机制。我们的初步数据揭示了一种令人着迷的、意想不到的愤怒转变 急性缺氧症与慢性缺氧症的信号传递。而RAGE信号在急性发作时上调Egr-1 缺氧，在后肢缺血中，尤其是在糖尿病中，RAGE抑制Egr-1和in的适应性诱导 平行的，减少血管生成和血流恢复。在本应用程序中，我们将探讨 单核/巨噬细胞或内皮细胞RAGE的特异性缺失以剖析其机制 通过愤怒的作用抑制血管生成和血流恢复。连同项目1和项目3，我们 将辨别RAGE在常见心血管应激中的微调机制，这三种 项目将使用Affymetrix阵列来开发不同细胞类型中RAGE信号的集成图景 以及各种情况。我们将在该计划的所有五年中使用所有三个核心。

Peripheral arterial disease (PAD) is a major complication of diabetes and is a leading cause of amputations of digits or limbs. My laboratory has focused for the past 15 years on the molecular regulation of genes in hypoxic stress. In the previous cycle, three major discoveries linked RAGE to regulation of acute responses to hypoxia: First, in cultured endothelial cells and monocytes/macrophages, acute exposure to hypoxia resulted in rapid release of AGE-reactive epitopes within minutes of hypoxic stress. Second, in the intact heart and in primary murine aortic and human aoilic endothelial cells, RAGE regulated rapid upregulation of Egr-1 in a manner suppressed by deletion or knockdown of RAGE and by aminoguanidine, an AGE inhibitor. Third, in collaboration with Project 1, we showed that monocytes/macrophages devoid of RAGE orthe RAGE cytoplasmic domain binding partner, diaphanous-1 or mDia-1, did not upregulate Egr-1 in acute hypoxia. To address the diabetes-relevant implications of these findings, we employed an in vivo model of hind limb ischemia induced by unilateral femoral artery ligation. Diabetes significantly impairs vascular repair mechanisms in this model. Our preliminary data reveal a fascinating and unexpected switch in RAGE signaling in acute vs. chronic oxygen deprivation ... whereas RAGE signaling upregulates Egr-1 in acute hypoxia, in hind limb ischemia, particularly in diabetes, RAGE suppresses adaptive induction of Egr-1 and, in parallel, reduces angiogenesis and blood flow recovery. In this application, we will probe the effects of specific deletion of RAGE in either monocytes/macrophages or endothelial cells to dissect the mechanisms by which RAGE action suppresses angiogenesis and blood flow recovery. Together with Projects 1&3, we will discern the fine-tuning mechanisms by which RAGE acts in common cardiovascular stresses, as all three Projects will use Affymetrix arrays to develop an integrated picture of RAGE signaling in distinct cell types and situations. We will use all three Cores in all five years ofthe Program.