Respiratory Endothelial Injury by Xanthine Oxide

描述(申请人提供)：肺上皮细胞功能障碍-a 肺泡的关键成分--毛细血管屏障--是发育的中心 急性肺损伤(ARDS)。细胞因子，如白介素1(IL-1)，氧化 应激与FasL在ARDS患者肺组织中的表达及其相互关系 ARDS是未知的。急性呼吸窘迫综合征的氧化应激源 患者也是未知的，但乙醛氧化酶(AOX)和黄嘌呤 ARDS患者体内升高的氧化还原酶(XOR)是细胞内的 氧自由基(O2*)产生酶，其调节可能有益于 阿兹。 我们的数据显示：1.给药后大鼠肺渗漏和炎症增加 体内实验前5h气管内注射IL-1。2.异或表达式， 别嘌醇抑制的02*的产生和上皮细胞的凋亡增加 大鼠在体气管内注射IL-1前24小时肺组织中的细胞。3. 喂钨减少的上皮细胞对肺XOR/AOX活性的抑制 大鼠气管内注射IL-1后24小时肺组织细胞凋亡的变化。 4.XOR/AOX表达和别嘌醇抑制02*的产生，但不是 IL-1作用24小时后肺上皮细胞凋亡率增加 体外培养。5.IL-1和02*可促进体外培养的肺上皮细胞Fas的表达。 6.含FasL前24小时气管内注射IL-1的大鼠肺灌洗 并在体外诱导Fas增加的肺上皮细胞凋亡 IL-1作用前24小时的水平。7.异或和AOX基因 IL-1/IL-6诱导大鼠肺上皮细胞表达上调 体外培养。 我们的特定假设是，增加IL-1会增加XOR和/或AOX 肺上皮细胞活性增加肺上皮细胞O2* 产生和Fas的表达。肺组织中伴随的IL-1依赖增加 炎症增加肺组织FasL水平并导致上皮细胞凋亡 这有助于肺损伤卡)。 我们的具体目标是确定IL-1诱导的机制 肺上皮细胞XOR和/或AOX的表达、02*的产生和上皮细胞 体内细胞凋亡(AIM 1)和体外细胞凋亡(AIM 2)及其影响 IL-1对肺上皮细胞XOR和/或AOX基因表达的调节 体外培养细胞(目标3)。 这种方法的意义将是确定基本的生理学， 关于XOR和AOX的细胞和分子方面，以深入了解 XOR和/或AOX是否有助于ARDS，并评估抑制是否 XOR和/或AOX具有治疗或预防以下事件的任何潜力 为急性呼吸窘迫综合征做出贡献。

DESCRIPTION (provided by applicant): Dysfunction of lung epithelial cells - a key component of the alveolar-capillary barrier - is central to the development of acute lung injury (ARDS). Cytokines, such as interleukin-1 (IL-1), oxidative stress and FasL are increased in lungs of ARDS patients but their relationship to each other and ARDS is unknown. The sources of oxidative stress in ARDS patients are also unknown but aldehyde oxidase (AOX) and xanthine oxidoreductase (XOR), which is increased in ARDS patients, are intracellular oxygen radical (O2*) generating enzymes whose regulation might be of benefit in ARDS. Our data shows that: 1. Leak and inflammation increased in lungs of rats given IL-1 intratracheally 5h before in vivo. 2. XOR expression, allopurinol-inhibitable 02* production, and apoptosis increased in epithelial cells in lungs of rats given IL-1 intratracheally 24h before in vivo. 3. Inhibition of lung XOR/AOX activity by tungsten feeding decreased epithelial cell apoptosis in lungs of rats given IL-1 intratracheally 24h before in vivo. 4. XOR/AOX expression and allopurinol-inhibitable 02* production, but not apoptosis, increased in lung epithelial cells treated with IL-1 24h before in vitro. 5. IL-1 and 02* increased lung epithelial cell Fas expression in vitro. 6. Lung lavage from rats given IL-1 intratracheally 24h before contained FasL and caused apoptosis of lung epithelial cells in vitro that had increased Fas levels following IL-1 treatment 24h before in vitro. 7. XOR and AOX gene expression was increased in lung epithelial cells treated with IL-1/IL-6 in vitro. Our specific hypothesis is that increased IL-1 increases XOR and/or AOX activity in lung epithelial cells increasing lung epithelial cell O2* production and Fas expression. Concomitant IL-1 dependent increases in lung inflammation increase lung FasL levels and produce epithelial cell apoptosis which contributes to lung injury CARDS). Our specific aims are to determine the mechanisms responsible for IL-1 induced lung epithelial cell XOR and/or AOX expression, 02* production and epithelial cell apoptosis in vivo (Aim 1) and in vitro (Aim 2) and to determine the effect of IL-1 on the regulation of XOR and/or AOX gene expression in lung epithelial cells in vitro (Aim 3). The significance of this approach will be to determine basic physiologic, cellular and molecular aspects regarding XOR and AOX, to gain insight into whether XOR and/or AOX contribute to ARDS, and to evaluate whether inhibiting XOR and/or AOX holds any potential for treating or preventing events that contribute to ARDS.