Mechanisms of Asbestos-Induced CIca1 and Mucin in Lung Epithelium

气道粘液分泌过多是许多肺部病变的显著特征。确定其在以下方面的作用： 空气中颗粒物引起的肺部疾病恶化是这一应用的重点，也是未来的重点。 提案主要目标是揭示石棉改变的调节表达的信号通路。 hclcal/mclcaS和muc5ac，这两个基因参与粘蛋白的产生和/或分泌。这一假设将 在3个特定目标中进行测试，包括体内和体外方法以阐明信号传导 控制这些基因调节的途径，以及它们参与石棉诱导的粘液 化生我们的第一个假设是，mclcaS的表达和粘液产生的发展将是 与通过吸入接触温石棉的正常小鼠相比，CC10-dnMEK小鼠的抑郁程度更高。 此外，细支气管气道内的Clara细胞将获得产生和分泌粘液的能力 石棉污染后。为了验证这一假设，我们将观察石棉诱导的肺基因变化， 小鼠上皮细胞表达上皮细胞特异性dnMEK转基因，我们先前在 实验室第二种假说认为石棉纤维通过诱导hclcal和mucSac的表达， 改变表皮生长因子受体（EGFR）/丝裂原活化蛋白激酶激酶-1（MEK）/激活剂 蛋白-1（AP-1）信号通路通过产生活性氧（ROS）。我们的第三 假设石棉诱导的MucSac的产生需要存在和上调 hClcal，并且这种诱导依赖于通过EGFR/MEK/AP-1的信号传导。实验 对于目的2和3，将使用MARK信号传导抑制剂在人肺上皮细胞系中进行 途径和si（小干扰）-RNA构建体。肺损伤关键基因的研究 石棉暴露后，可以帮助制定治疗和预后策略， 与石棉有关的肺部疾病。这些研究的长期目标是阐明基因表达的机制。 致病性环境污染物的调节，以及这些事件如何导致疾病， 纤维化、哮喘、慢性阻塞性肺病（COPD）、肺气肿和癌症。希望在于 提高我们对这些疾病的基本认识将导致适当的风险评估和未来的 制定空气传播相关疾病的治疗策略。

Airway mucus hypersecretion is a prominent feature of numerous lung pathologies. Determining its role in exacerbation of lung disease by airborne particulates is the focus of this application, as well as future proposals. The primary goal is to unveil signaling pathways altered by asbestos that regulate the expression of hclcal/mclcaS and muc5ac, two genes involved in mucin production and/or secretion. This hypothesis will be tested in 3 specific aims which encompass both in vivo and in vitro approaches to elucidate signaling pathways that control the regulation of these genes, and their involvement in asbestos-induced mucus metaplasia. Out first hypothesis is that expression of mclcaS and development of mucus production will be depressed in CC10-dnMEK mice compared to normal mice exposed to chrysotile asbestosvia inhalation. Furthermore, Clara cells within the bronchiolar airways will acquire the ability to produce and secrete mucus following asbestos insult. To test this hypothesis, we will observe asbestos-induced gene changes in lung epithelial cells of mice expression an epithelial cell-specific dnMEK transgene previously characterized in our lab. The second hypothesis states that asbestos fibers induce the expression of hclcal and mucSac by altering epidermal growth factor receptor (EGFR)/mitogen activated protein kinase kinase-1 (MEK)/activator protein-1 (AP-1) signaling pathways through the generation of reactive oxygen species (ROS). Our third hypothesis is that the asbestos-induced production of MucSac requires the presence and up-regulation of hClcal, and that this induction is dependant upon signaling through the EGFR/MEK/AP-1. The experiments for Aims 2 and 3 will be carried out in human lung epithelial cell lines using inhibitors of MARK signaling pathways and si (small interference)-RNA constructs. Elucidation of critical genes involved in lung injury following asbestos exposure could aid in the development of therapeutic and prognostic strategies to treat asbestos-associated lung diseases. The long term goal of these studies is elucidating mechanisms of gene regulation by pathogenic environmental contaminants, and how these events lead to diseases such as fibrosis, asthma, chronic obstructive pulmonary disease (COPD), emphysema, and cancer. The hope is that enhancing our basic understanding of these diseases will lead to appropriate risk assessment and future development of therapeutic strategies for airborne related diseases.