LEUKOCYTE ADHESION IN COPPER DEFICIENT MICROCIRCULATION

描述(申请人提供)：微血管对炎症刺激的反应的调节高度依赖于中性粒细胞和内皮细胞之间的相互作用。我们已经显示了膳食铜在炎症过程中的各种内皮相互作用中的重要作用，包括一氧化氮(NO)介导的血管扩张、大分子渗漏和血栓形成。最近，我们研究了膳食铜在微血管控制机制中的作用，重点是白细胞/内皮细胞的黏附。我们已经证明，饮食铜限制导致中性粒细胞/内皮细胞黏附和迁移的组织特异性变化。中性粒细胞聚集、黏附分子ICAM-1和转录因子NF-kappaB在缺铜大鼠肺中的表达均高于缺铜对照组。根据这些结果，我们推测，膳食铜缺乏对白细胞和肺血管内皮细胞具有启动作用，从而使肺对炎症刺激变得敏感，更容易发生急性肺损伤。因此，本研究的具体目的是：1)确定日粮铜在肺微循环中白细胞/内皮细胞相互作用中的作用；2)确定铜缺乏引发急性炎症细胞的机制；3)确定在体内动物微循环中，何种浓度的铜使炎症机制增强。目的1将使用体内和体外肺微循环模型来研究白细胞/内皮细胞的黏附和趋化作用。目的#2研究铜在核因子-kB信号通路和中性粒细胞启动中的作用。目标#3将在铜边缘饮食的条件下检查这些机制。这些实验具有特别的相关性，因为对典型西方饮食的分析表明，这些饮食中有1/3到1/2提供的铜可能低于900毫克/天的RDA。

DESCRIPTION (provided by applicant): Regulation of the microvascular response to inflammatory stimuli is highly dependent upon the interactions between neutrophils and the endothelium. We have shown a significant role for dietary copper in various endothelial interactions in the inflammatory process, including nitric oxide (NO)-mediated vasodilation, macromolecular leakage, and thrombosis. Recently, we have studied the role of dietary copper in microvascular control mechanisms with an emphasis on leukocyte/endothelial adhesion. We have demonstrated that dietary copper restriction causes tissue-specific changes in neutrophil/endothelial adhesion and transmigration. Neutrophil accumulation, the expression of the adhesion molecule ICAM-1 and the transcription factor NF-kappaB are all greater in the lungs of copper-deficient rats compared to copper-adequate controls. Based on these results, we hypothesize that dietary copper deficiency has a priming effect on leukocytes and pulmonary vascular endothelial ceils such that the lung becomes hypersensitive to inflammatory stimuli and more susceptible to the development of acute lung injury. Therefore the specific aims of this study are to: 1) determine the role of dietary copper in leukocyte/endothelial cell interactions in the lung microcirculation; 2) determine the mechanisms by which copper deficiency primes cells for acute inflammation and 3) determine at what concentration of dietary copper the inflammatory mechanisms become enhanced in the in vivo animal microcirculation. Aim #1 will use both in vivo and in vitro models of the lung microcirculation to study leukocyte/endothelial cell adhesion and chemotaxis. Aim #2 will study the role of copper in the NF-kB signaling pathway and in neutrophil priming. Aim #3 will examine these mechanisms under conditions of copper-marginal diets. These experiments have particular relevance since analysis of typical Western diets suggest that 1/3 to 1/2 of those diets may provide less than the RDA of 900mg Cu/day.