Role of macrophages in organophosphorus pesticide-induced airway hyperreactivity

巨噬细胞在有机磷农药引起的气道高反应性中的作用

• 批准号: 8272650
• 负责人: ALLISON Deborah FRYER
• 金额: $ 34.29万
• 依托单位: UNIVERSITY OF CALIFORNIA AT DAVIS
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-07-07 至 2015-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8272650
• 关键词: Acetylcholine; Acetylcholinesterase; Address; Agonist; Allergic; Alveolar Macrophages; Animals; Antigens; Asthma; Brain; Bronchoalveolar Lavage; Bronchoconstriction; Carbamates; Cavia; Cell Culture Techniques; Child; Cholinesterases; Coculture Techniques; Data; Dichloromethylene Diphosphonate; Dose; Encapsulated; Epidemiologic Studies; Exposure to; Functional disorder; Funding; Goals; Grant; Health; Human; Individual; Inflammation; Inflammatory; Insecticides; Interferons; Interleukin-5; Light; Link; Liposomes; Lung; Measurement; Measures; Mediating; Mediator of activation protein; Messenger RNA; Modeling; Molecular; Morphology; Muscarinic M2 Receptor; Nerve; Neuronal Plasticity; Neurons; Ozone; Parathion; Pesticides; Physiological; Pilocarpine; Prevalence; Preventive; Proteins; Public Health; Rattus; Reporting; Risk; Role; Saline; Site; Structure; Structure of parenchyma of lung; Symptoms; TNF gene; Testing; Therapeutic; Time; United States National Institutes of Health; Work; airway hyperresponsiveness; cytokine; eosinophil; exposed human population; functional loss; in vivo; macrophage; nerve agent; neuroblastoma cell; neurotoxicity; novel; pesticide exposure; public health relevance; pyrethroid; receptor expression; receptor function; respiratory smooth muscle; response

DESCRIPTION (provided by applicant): We have demonstrated that in a guinea pig model, organophosphorus pesticides (OPs) cause airway hyperreactivity that is dose-related and associated with the functional loss of autoinhibitory muscarinic M2 receptors that normally limit acetylcholine release from parasympathetic nerves that innervate airway smooth muscle. We recently reported that sensitization to antigen alters the mechanisms underlying OP-induced airway hyperreactivity to involve IL-5-dependent mechanisms in the sensitized but not the non-sensitized guinea pig. How OPs cause neuronal M2 dysfunction in the non-sensitized animal is not known but our preliminary data indicate that this effect is not mediated by cholinesterase inhibition or direct antagonistic interactions with neuronal M2 receptors. Rather, OPs appear to influence neuronal M2 receptor function indirectly via effects on macrophages since depletion of macrophages using liposome-encapsulated clodronate protects against OP-induced airway hyperreactivity. It is our hypothesis that OPs activate macrophages to upregulate expression and release of inflammatory cytokines previously shown to cause M2 receptor dysfunction in various models of airway hyperreactivity. We propose four Aims to test this hypothesis. In Aim 1, we will use in vivo physiological measurements to confirm that macrophages mediate airway hyperreactivity caused by OPs and determine whether their role changes over time, as has been observed for eosinophils in ozone-induced airway hyperreactivity. Aim 2 will utilize macrophages isolated from bronchoalveolar lavage collected from OP-treated versus untreated guinea pigs guinea pigs to examine the effect of OPs on macrophage expression and release of inflammatory cytokines implicated in airway hyperreactivity. In Aim 3, we will use primary nerve cell cultures to determine whether OP- induced macrophage mediators interact with nerves directly to alter M2 receptor expression or function or the structural plasticity of nerves. Aim 4 will confirm the in vivo physiological relevance of OP-induced macrophage mediators identified in aims 2 and 3. Mechanistic studies are critical to developing preventive and therapeutic approaches for OP-induced airway hyperreactivity, which are likely to differ between sensitized (allergic) and non-sensitized individuals, and for determining the risks to human health posed by OP exposures. The public health implications of these studies are significant in light of the increasing prevalence of asthma, the wide spread exposure of humans and especially children to OPs and the credible threat of terrorist use of OP pesticides and nerve agents. PUBLIC HEALTH RELEVANCE: Recent epidemiological studies suggest a link between exposure to organophosphorus pesticides (OPs) and asthma. Our previous work confirms this link by demonstrating that OPs cause airway hyperreactivity, a major symptom of asthma, in a guinea pig model. The goal of this project is to elucidate the mechanism(s) by which OPs cause airway hyperreactivity, which will be critical to developing effective preventive and therapeutic approaches to OP-induced airway hyperreactivity. Given the documented widespread exposure to OPs not only in the U.S. but worldwide, and the credible threat of terrorist use of OPs, the proposed work is of significant public health relevance.

描述(申请人提供)：我们已经证明，在豚鼠模型中，有机磷农药(OPs)引起的呼吸道高反应性与剂量相关，并与自身抑制性M_2受体的功能丧失有关，M_2受体通常限制支配呼吸道平滑肌的副交感神经释放乙酰胆碱。我们最近报道，在致敏的豚鼠中，对抗原的致敏改变了OP诱导的气道高反应性的潜在机制，涉及到IL-5依赖的机制，而不是非致敏的豚鼠。OPs如何导致非致敏动物神经元M2功能障碍尚不清楚，但我们的初步数据表明，这种作用不是通过胆碱酯酶抑制或与神经元M2受体的直接拮抗相互作用来介导的。相反，OPs似乎通过对巨噬细胞的作用间接影响神经元M2受体的功能，因为使用脂质体包裹的氯屈磷酸耗尽巨噬细胞可以保护Op诱导的呼吸道高反应性。我们的假设是，OPs激活巨噬细胞，上调炎症细胞因子的表达和释放，在各种气道高反应性模型中，炎性细胞因子可导致M2受体功能障碍。我们提出了四个目标来检验这一假说。在目标1中，我们将使用体内生理测量来证实巨噬细胞介导了OPs引起的气道高反应性，并确定它们的作用是否随着时间的推移而改变，就像已经观察到的嗜酸性粒细胞在臭氧诱导的气道高反应性中所观察到的那样。目的2利用从经OP治疗的豚鼠和未经OP治疗的豚鼠的支气管肺泡灌洗液中分离的巨噬细胞，研究OP对巨噬细胞表达和释放与呼吸道高反应性有关的炎性细胞因子的影响。在目标3中，我们将使用原代培养的神经细胞来确定OP诱导的巨噬细胞介质是否直接与神经相互作用以改变M2受体的表达或功能或神经的结构可塑性。AIM 4将确认AIMS 2和AIMS 3中确定的OP诱导的巨噬细胞介质在体内的生理学相关性。机制研究对于开发OP诱导的呼吸道高反应性的预防和治疗方法至关重要，致敏(过敏)和非致敏的个体可能有所不同，并且对于确定OP暴露对人类健康构成的风险至关重要。鉴于哮喘患病率不断上升，人类尤其是儿童广泛暴露于有机磷农药，以及恐怖分子使用有机磷农药和神经毒剂的可信威胁，这些研究对公共卫生的影响重大。 公共卫生相关性：最近的流行病学研究表明，接触有机磷杀虫剂(OPs)与哮喘之间存在联系。我们之前的工作证实了这种联系，在豚鼠模型中证明了OP引起呼吸道高反应性，这是哮喘的主要症状。本项目的目标是阐明OP引起呼吸道高反应性的机制(S)，这对于开发有效的预防和治疗OP诱导的气道高反应性的方法至关重要。鉴于记录在案的不仅在美国，而且在世界范围内广泛暴露于OPS，以及恐怖分子使用OPS的可信威胁，拟议的工作具有重大的公共卫生意义。