The Role of Iron In Pulmonary Fibrosis

项目总结 特发性肺纤维化(IPF)是一种慢性肺部疾病，确诊后中位生存期为3年。 这种疾病没有治愈的方法。虽然病因尚不清楚，但与此相关的主要风险因素之一 与IPF一起吸入的是富含铁的颗粒物，如石棉和香烟烟雾。然而，具体的角色是 铁在特发性肺纤维化发病机制中的作用是一个研究较少的领域。这个项目的长期目标是阐明 从而为IPF的发病机制及有效治疗的发展提供新的思路。当前的目标是 应用于了解铁在特发性肺纤维化发病机制中的作用及其机制 重点是铁介导的肺成纤维细胞的激活。 有证据表明，铁在肺中积聚，并导致肺纤维化。然而， 这两个过程的分子机制尚不清楚。我们的初步研究已经确定了铁的出口 基因溶质载体家族40成员1(SLC40A1)是肺成纤维细胞铁蓄积的关键基因。我们 我们还鉴定了两个新的铁调控基因，SH3结构域环指1(SH3RF1)，一个E3 泛素蛋白连接酶和同源结构域相互作用蛋白激酶2(HIPK2)，共转录调节因子和 提供了这两个基因调节肺成纤维细胞激活的证据。根据我们的初步研究，我们的 总体假设是，由于SLC40A1减少导致肺成纤维细胞中铁水平升高导致 SH3RF1表达下调和HIPK2上调激活肺成纤维细胞 表情。这一假说将通过使用原代人肺的体外研究相结合的方式进行验证。 两种小鼠肺纤维化模型中的成纤维细胞和体内策略 干预措施。目的研究SLC40A1在肺成纤维细胞中蓄积铁的机制。 以及SH3RF1在铁介导的肺成纤维细胞活化中的调节和功能作用 功能获得和诱变方法。AIM II将定义铁激活肺的机制 利用基因操作、免疫共沉淀、泛素化和分子信号转导HIPK2的成纤维细胞 通径分析。目的III将确定铁和HIPK2对两个临床前肺纤维化的体内影响 利用成纤维细胞特异性基因缺失建立博莱霉素和石棉诱导的小鼠肺纤维化模型 Hipk2和药理抑制剂。拟议的研究将建立铁的分子机制。 肺成纤维细胞的蓄积及SH3RF1和HIPK2在肺成纤维细胞激活中的新作用。

PROJECT SUMMARY Idiopathic pulmonary fibrosis (IPF) is a chronic lung disease with a median survival of 3 years after diagnosis. There are no cures for this disease. Although the etiology is still unclear, one of the major risk factors associated with IPF is inhaled iron-rich particulate matter, such as asbestos and cigarette smoke. However, the specific role of iron in the pathogenesis of IPF is an understudied area. The long-term goal of this project is to elucidate the pathogenesis of IPF and thus to advance the development of effective therapies. The objective of the current application is to understand the contribution of iron to the pathogenesis of IPF and the underlying mechanisms with a focus on the iron-mediated activation of lung fibroblasts. There is evidence showing that iron accumulates in the lung and contributes to lung fibrosis. However, the molecular mechanisms for both processes are unclear. Our preliminary studies have identified the iron export gene solute carrier family 40 member 1 (SLC40A1) as a key gene for iron accumulation in lung fibroblasts. We have also identified two novel iron-regulated genes, SH3 domain-containing ring finger 1 (SH3RF1), an E3 ubiquitin protein ligase, and homeodomain-interacting protein kinase 2 (HIPK2), a cotranscriptional regulator and provided evidence that both genes regulate lung fibroblast activation. Based on our preliminary studies, our overall hypothesis is that an elevated level of iron in lung fibroblasts due to reduced SLC40A1 leads to the activation of lung fibroblasts via the downregulation of SH3RF1 expression and the upregulation of HIPK2 expression. The hypothesis will be tested by a combination of in vitro studies using primary human lung fibroblasts and in vivo strategies in two mouse lung fibrosis models using pharmacological and genetic interventions. Aim I will determine the mechanisms by which iron accumulates in lung fibroblasts via SLC40A1 and the regulation and functional roles of SH3RF1 in iron-mediated lung fibroblast activation using loss- and gain-of-function and mutagenesis approaches. Aim II will define the mechanisms by which iron activates lung fibroblasts via HIPK2 using gene manipulation, coimmunoprecipitation, ubiquitination and molecular signaling pathway analyses. Aim III will determine the in vivo effects of iron and HIPK2 on lung fibrosis in two preclinical mouse models of bleomycin- and asbestos-induced lung fibrosis using fibroblast-specific genetic deletion of Hipk2 and pharmacological inhibitors. The proposed studies will establish the molecular mechanisms of iron accumulation in lung fibroblasts and novel roles for SH3RF1 and HIPK2 in lung fibroblast activation.