Quercetin and Innate Immune Responses in COPD

描述（由申请人提供）：槲皮素（3，3 '，4'，5，7-五羟基黄酮）是人类饮食中的主要类黄酮。它存在于洋葱、花椰菜、苹果、浆果和茶中，也存在于银杏和圣约翰草的提取物中，这两种都是流行的健康补充剂。黄酮类化合物具有共同的化学结构，由两个通过三个碳连接的酚环组成。槲皮素具有有效的抗氧化作用，与自由基物质结合形成反应性相当低的苯氧基自由基。槲皮素还对几种脂质、蛋白酪氨酸和丝氨酸/苏氨酸激酶具有抑制作用，包括磷脂酰肌醇（PI）3-激酶。 慢性阻塞性肺疾病（COPD）的特征在于具有杯状细胞增生的气道炎症、不可逆的气道阻塞、下气道的慢性细菌感染、粘膜纤毛清除减少、肺气肿;以及先天免疫受损。具有抗氧化和抗炎特性的黄酮可能会影响慢性炎症性疾病，如COPD。在荷兰COPD患者中，黄酮醇（黄酮类化合物的一个亚类，包括槲皮素和山奈酚）的饮食摄入量与肺功能（FEV 1）呈正相关，与慢性咳嗽和呼吸困难呈负相关（6）。此外，在三个欧洲国家，含多酚水果的摄入量与20年COPD死亡率呈负相关（7）。总之，这些研究表明，槲皮素和其他黄酮类化合物可能对COPD的预后产生积极影响。我们已经表明，槲皮素，通过灌胃针，阻断气道高反应性和单核细胞趋化蛋白（MCP-1/CCL 2）的表达在哮喘小鼠模型中通过衰减信号通过PI 3-激酶/Akt/核因子（NF）-？B途径。在后一项研究中，槲皮素也增加气道上皮细胞真核起始因子（eIF）-2？磷酸化是限制病毒蛋白合成和复制的抗病毒反应中的关键事件。此外，我们的初步研究结果表明，槲皮素抑制响应铜绿假单胞菌感染的气道上皮细胞和人单核细胞衍生的巨噬细胞的白细胞介素（IL）-8/CXCL8表达。槲皮素还降低了铜绿假单胞菌对上皮细胞的侵袭。槲皮素减少了脂多糖（LPS）和弹性蛋白酶处理的具有COPD典型生理和组织学变化的小鼠的肺部炎症和弹性回缩损失，以及这些“COPD”小鼠对不可分型H.流感。最后，槲皮素抑制鼻病毒（RV）在培养的气道上皮细胞的内化，并减少RV诱导的嗜肺炎症在体内。基于这些观察，我们提出了槲皮素调节COPD先天免疫反应的一般假设。为了验证这一假设，我们提出了以下具体目标。 具体目标1：确定槲皮素对COPD小鼠模型气道炎症和组织破坏的影响。我们假设：1）槲皮素减弱由弹性蛋白酶和LPS（香烟烟雾的一种成分）引起的气道炎症和肺气肿变化; 2）槲皮素通过抑制CD 14、细胞外信号调节激酶（ERK）和p38丝裂原活化蛋白（MAP）激酶向脂筏的募集来减少LPS诱导的肺泡巨噬细胞中的炎症反应; 3）LPS诱导的肿瘤坏死因子（TNF）-1表达的减少，进而减弱C-X-C趋化因子和粘蛋白糖蛋白的上皮细胞表达;和4）槲皮素防止巨噬细胞和气道上皮细胞中LPS诱导的氧化应激。具体目标2：确定槲皮素对COPD小鼠模型中细菌感染的先天性反应的影响。我们推测：1）感染H.例如，对于流感病毒或铜绿假单胞菌，槲皮素抑制LPS和弹性蛋白酶处理的“COPD小鼠”中的肺部炎症; 2）槲皮素抑制气道上皮细胞中Toll样受体（TLR）介导的促炎反应; 3）槲皮素减弱气道上皮细胞中PI 3-激酶依赖性细菌摄取;和4）槲皮素通过抑制上皮细胞中细菌诱导的氧化应激来降低细胞毒性作用。 具体目标3：确定槲皮素对COPD小鼠模型中鼻病毒感染的先天反应的影响。我们已经开发了一个动物模型的RV感染使用RV 1B，一个小集团RV结合低密度脂蛋白受体（LDL-R）。我们假设：1）槲皮素抑制RV感染的LPS和弹性蛋白酶处理的“COPD小鼠”中的嗜肺气道炎症; 2）槲皮素抑制RV在气道上皮细胞中的内化; 3）槲皮素降低气道上皮细胞C-X-C趋化因子表达;和4）槲皮素增加单个核细胞中干扰素（IFN）-3的表达，并增加真核起始因子（eIF）的磷酸化。a1，从而降低病毒载量。 了解槲皮素在COPD小鼠模型中调节炎症的基本机制可能会为这种毁灭性疾病带来新的治疗方法。 公共卫生部门：慢性阻塞性肺疾病（COPD）在美国是越来越常见的残疾和死亡原因，这种疾病的有效治疗方法很少。本研究旨在探讨槲皮素（一种具有抗氧化和抗炎作用的植物衍生物）对COPD小鼠模型先天免疫反应的影响。我们将研究槲皮素对COPD发病机制的影响，以及细菌和病毒感染引起的COPD恶化。基本的细胞和生化机制也将被检查。这一建议可能会导致一种新的COPD营养治疗。

DESCRIPTION (provided by applicant): Quercetin (3,3',4',5,7-pentahydroxyflavone) is the major flavonoid in the human diet. It is found in onions, broccoli, apples, berries and tea, and present in extracts from Ginko biloba and St. John's Wort, both popular health supplements. Flavonoids share a common chemical structure consisting of two phenol rings linked through three carbons. Quercetin has potent antioxidant effects, combining with free radical species to form considerably less reactive phenoxy radicals. Quercetin also has inhibitory effects on several lipid, protein tyrosine and serine/threonine kinases, including phosphatidylinositol (PI) 3-kinase. Chronic obstructive pulmonary disease (COPD) is characterized by airway inflammation with goblet cell hyperplasia, irreversible airway obstruction, chronic bacterial infection of the lower airways, reduced mucociliary clearance, emphysema; and impaired innate immunity. Flavonoids with antioxidant and anti-inflammatory properties may influence chronic inflammatory diseases such as COPD. Dietary intake of flavonols (a subclass of flavonoids including quercetin and kaempferol) has been positively associated with pulmonary function (FEV1) and inversely associated with chronic cough and breathlessness in Dutch COPD patients (6). Further, intake of polyphenol-containing fruit was inversely correlated with 20-yr COPD mortality in three European countries (7). Together these studies suggest that quercetin and other flavanoids may positively influence outcome in COPD. We have shown that quercetin, administered by gavage needle, blocks airways hyper-responsiveness and monocyte chemoattractant protein (MCP-1/CCL2) expression in a mouse model of asthma by attenuating signaling through a PI 3-kinase/Akt/nuclear factor (NF)-?B pathway. In the latter study, quercetin also increased airway epithelial cell eukaryotic initiation factor (eIF)-2? phosphorylation, a key event in the antiviral response which limits viral protein synthesis and replication. In addition, results from our pilot studies suggest that quercetin inhibits interleukin (IL)-8/CXCL8 expression from airway epithelial cells and human monocyte- derived macrophages in response to P. aeruginosa infection. Quercetin also decreased invasion of epithelial cells by P. aeruginosa. Quercetin reduced lung inflammation and loss of elastic recoil in lipopolysaccharide (LPS) and elastase-treated mice with physiologic and histologic changes typical of COPD, as well as the inflammatory response of these "COPD" mice to non-typeable H. influenzae. Finally, quercetin inhibited internalization of rhinovirus (RV) in cultured airway epithelial cells and reduced RV-induced neutrophilic inflammation in vivo. Based on these observations, we offer the general hypothesis that quercetin modulates innate immune responses in COPD. To test this hypothesis, we propose the following Specific Aims. Specific Aim 1: Determine the effects of quercetin on airway inflammation and tissue destruction in a mouse model of COPD. We hypothesize that: 1) quercetin attenuates airways inflammation and emphysematous changes caused by elastase and LPS, a constituent of cigarette smoke; 2) quercetin reduces LPS-induced inflammatory responses in alveolar macrophages by inhibiting recruitment of CD14, extracellular signal regulated kinase (ERK) and p38 mitogen-activated protein (MAP) kinase to lipid rafts; 3) reduction of LPS-induced tumor necrosis factor (TNF)-1 expression, in turn, attenuates epithelial cell expression of C-X-C chemokines and mucin glycoproteins; and 4) quercetin prevents LPS-induced oxidative stress in macrophages and airway epithelial cells. Specific Aim 2: Determine the effects of quercetin on the innate response to bacterial infection in a mouse model of COPD. We hypothesize that: 1) after infection with H. influenzae or P. aeruginosa, quercetin inhibits lung inflammation in LPS and elastase-treated "COPD mice;" 2) quercetin inhibits Toll-like receptor (TLR)-mediated pro-inflammatory responses in airway epithelial cells; 3) quercetin attenuates PI 3-kinase- dependent bacterial uptake in airway epithelial cells; and 4) quercetin reduces cytotoxic effects by inhibiting bacteria-induced oxidative stress in epithelial cells. Specific Aim 3: Determine the effects of quercetin on the innate response to rhinoviral infection in a mouse model of COPD. We have developed an animal model of RV infection using RV1B, a minor group RV which binds to the low-density lipoprotein receptor (LDL-R). We hypothesize that: 1) quercetin inhibits neutrophilic airway inflammation in RV-infected LPS- and elastase-treated "COPD mice;" 2) quercetin inhibits internalization of RV in airway epithelial cells; 3) quercetin decreases airway epithelial cell C-X-C chemokine expression; and 4) quercetin increases the expression of interferon (IFN)-3 in mononuclear cells and increases the phosphorylation of eukaryotic initiation factor (eIF)-a1 in airway epithelial cells, thereby reducing viral load. Understanding the basic mechanisms by which quercetin modulates inflammation in a mouse model of COPD may lead to a new treatment for this devastating disease. PUBLIC HEALTH REVELANCE: Chronic obstructive pulmonary disease (COPD) is increasingly common cause of disability and death in the U.S. There are few effective treatments for this disease. This proposal examines the effects of quercetin, a plant derivative with antioxidant and anti-inflammatory actions, on the innate immune response in a mouse model of COPD. We will examine the effects of quercetin on the pathogenesis of COPD, as well as exacerbations of COPD caused by bacterial and viral infections. Underlying cellular and biochemical mechanisms will also be examined. This proposal may lead to a new nutraceutical treatment for COPD.