Targeting Airway Inflammation from Concentrated Animal Feeding Operation Dust

描述(申请人提供)：集中饲养动物(CAFO)的农民和工人患有与工作有关的呼吸系统疾病，特别是慢性支气管炎和慢性阻塞性肺疾病(COPD)。尽管CAFO中的多种物质可能导致疾病，但来自这些设施的粉尘被公认为是一种重要的呼吸系统健康危害。我们之前的工作集中在确定CAFO粉尘导致肺部炎症的机制上。重要的是，我们已经确定了这种CAFO粉尘诱导的肺炎症机制的三个关键要素，我们认为它们是治疗这种重要的职业性肺部疾病的良好靶点：1)细胞因子的释放，重点是依赖肿瘤坏死因子α的气道上皮细胞释放IL-6和IL-8，随后依次激活呼吸道上皮蛋白激酶C亚型(PKC)，然后是α，然后是epsilon；2)cAMP依赖的蛋白激酶(PKA)的抗炎作用；以及3)CAFO粉尘中存在的促炎蛋白。这项提案概述了我们将如何使用临床前动物模型来破译靶向这三个可能抑制和/或逆转CAFO粉尘引起的肺部疾病的机械因素的相对价值。为此，我们在小鼠模型中证明了吸入粉尘提取物会在体内引起呼吸系统炎症，该模型具有在猪隔离设施中工作的人所见的所有肺部疾病的显著特征。在这次更新中，我们提出了一种策略，在临床前研究中利用这种小鼠模型，旨在确定上述哪些治疗靶点是可行和有效的。我们假设：CAFO粉尘诱导的肺部炎症可以通过阻断PKC亚型触发的呼吸道细胞因子释放、激活PKA和抑制粉尘衍生的蛋白水解酶及其细胞靶点来治疗。我们将通过三个特定的目标来检验这一假说：目标1：建立特异性靶向肿瘤坏死因子-α、白介素6和白介素8的药物如何在体内调节粉尘提取物诱导的肺部炎症。目的2：确定增强PKA的药物，特别是治疗性β-肾上腺素能激动剂，在体外和体内如何抑制粉尘提取物诱导的PKC亚型激活和减轻肺部炎症。目的：确定蛋白水解酶在粉尘提取物诱导的肿瘤坏死因子-α/白介素6/白介素8在体外和体内组织炎症中的重要性，寻找减轻粉尘提取物蛋白水解酶诱导的炎症变化的潜在靶点。我们的提案旨在提供临床前细胞、肺切片和动物数据，这些数据将促进旨在将潜在干预措施引入工作场所的转化性研究。) 公共卫生相关性：在我们之前的工作中，我们确定了猪限制饲养操作中的粉尘提取物会导致呼吸道内的细胞通过细胞内信号蛋白激酶C(PKC)释放特定的炎症介质，即TNF-1、IL-6和IL-8。我们还证明，这种粉尘提取物在小鼠模型中会引起炎症，其特征与工作人员的相似。在这项应用中，我们将使用我们的小鼠模型进行临床前研究，以确定靶向特定的介质(TNF-1、IL-6和IL-8)和通路(PKC和cAMP依赖的蛋白激酶)以及粉尘中的物质(蛋白水解酶)是否会减少肺部的炎症，长期目标是开发新的治疗策略，在呼吸道炎症导致工人疾病之前减少它。

DESCRIPTION (provided by applicant): Farmers and workers in concentrated animal feeding operations (CAFOs) experience work-related respiratory disease, particularly chronic bronchitis and chronic obstructive pulmonary disease (COPD). Although multiple substances in CAFOs may contribute to disease, dust from these facilities is well recognized as an important respiratory health hazard. Our previous work has been focused on defining mechanisms by which CAFO dust results in lung inflammation. Importantly, we have identified three critical elements of this CAFO dust-induced lung inflammation mechanism that we propose make excellent therapeutic targets for treatment of this important occupational lung disorder: 1) cytokine release, focusing on the TNF-alpha-dependent airway epithelial cell release of IL-6 and IL-8 with sequential activation of the airway epithelial protein kinase C isoforms (PKC), alpha followed by epsilon; 2) the anti-inflammatory effects of the cyclic AMP dependent protein kinase (PKA); and 3) pro-inflammatory proteases as triggers present in CAFO dust. This proposal outlines how we will use a pre-clinical animal model to decipher the relative value of targeting these three mechanistic elements that may dampen and/or reverse CAFO dust-induced lung disease. Toward this end, we have demonstrated that inhaled dust extract causes respiratory inflammation in vivo in a mouse model that has all of the prominent features of the pulmonary disorders seen in persons working in swine confinement facilities. In this renewal we propose a strategy to utilize this mouse model in preclinical studies aimed at determining which of the therapeutic targets outlined above are feasible and efficacious. We hypothesize that: CAFO dust-induced lung inflammation is treatable by blocking PKC isoform-triggered airway cytokine release, activating PKA and inhibiting dust-derived proteases and their cellular targets. We will test this hypothesis via three specific aims: Aim 1: Establish how agents that specifically target TNF-alpha, IL-6, and IL-8 modulate dust extract-induced lung inflammation in vivo. Aim 2: Determine how agents that augment PKA, especially therapeutic beta-adrenergic agonists, dampen dust extract-induced PKC isoform activation and attenuate lung inflammation in vitro and in vivo. Aim 3: Determine the importance of proteases in dust extract-induced TNF-alpha/IL-6/IL-8 in vitro and in tissue inflammation in vivo and identify potential targets for attenuating the dust extract protease-induced inflammatory changes. Our proposal is designed to provide pre-clinical cell, lung slice, and animal data that will facilitate translational studies aimed at bringing potential interventions into the workplace. ) PUBLIC HEALTH RELEVANCE: In our previous work, we determined that dust extract from swine confined animal feeding operations causes cells lining airways to release specific inflammatory mediators, namely TNF-1, IL-6, and IL-8 via the intracellular signal protein kinase C (PKC). We have also demonstrated that this dust extract causes inflammation in a mouse model that has features similar to that seen in workers. In this application, we will perform pre-clinical studies using our mouse model to determine if targeting specific mediators (TNF-1, IL-6, and IL-8) and pathways (PKC and cAMP dependent protein kinase) as well as substances in the dust (proteases) will decrease inflammation in the lungs, with a long-term goal of developing new treatment strategies to reduce airway inflammation before it causes disease in workers.