RAGE and the host response to hypoxic stress

外周动脉疾病（PAD）是糖尿病的主要并发症，也是截肢的主要原因 手指或四肢的在过去的15年里，我的实验室一直专注于基因的分子调控， 低氧应激在上一个周期中，有三项重大发现将神经元与急性反应的调节联系起来 缺氧：首先，在培养的内皮细胞和单核细胞/巨噬细胞中，急性暴露于缺氧 导致在缺氧应激的几分钟内快速释放AGE反应性表位。第二，在完整的 在原代鼠主动脉和人动脉内皮细胞中， Egr-1以通过缺失或敲低Egr-1和通过氨基胍（AGE抑制剂）抑制的方式表达。 第三，在与项目1的合作中，我们发现缺乏巨噬细胞的单核细胞/巨噬细胞可以在细胞内表达。 RAGE胞质结构域结合伴侣diaphanous-1或mDia-1在急性期并没有上调Egr-1 缺氧为了解决这些发现的糖尿病相关影响，我们采用了一种体内模型， 结扎一侧股动脉造成后肢缺血。糖尿病严重损害血管修复 这个模型中的机制。我们的初步数据揭示了一个迷人的和意想不到的开关， 急性缺氧与慢性缺氧的信号传导而Egr-1信号在急性炎症中上调， 在后肢缺血中，特别是在糖尿病中，缺氧抑制Egr-1的适应性诱导， 平行，减少血管生成和血流恢复。在本应用程序中，我们将探讨 在单核细胞/巨噬细胞或内皮细胞中特异性缺失β-内酰胺酶，以剖析其机制 通过该作用，血管生成抑制血管生成和血流恢复。与项目1&3一起，我们 将辨别出微调机制，通过它，在共同的心血管压力，因为所有三个 项目将使用Affymbers阵列来开发不同细胞类型中BMPs信号传导的综合图片 和情况。我们将在整个五年的计划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.