The Role of Iron In Pulmonary Fibrosis

铁在肺纤维化中的作用

基本信息

批准号：
10838699
负责人：
LIN LIU
金额：
$ 1.71万
依托单位：
OKLAHOMA STATE UNIVERSITY STILLWATER
依托单位国家：
美国
项目类别：
财政年份：
2023
资助国家：
美国
起止时间：
2023-08-23 至 2026-11-30
项目状态：
未结题

项目摘要

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.

项目概要特发性肺纤维化 (IPF) 是一种慢性肺部疾病，诊断后中位生存期为 3 年。这种疾病无法治愈。尽管病因尚不清楚，但相关的主要危险因素之一 IPF 是吸入富含铁的颗粒物，如石棉和香烟烟雾。但具体作用铁在 IPF 发病机制中的作用尚待研究。该项目的长期目标是阐明 IPF 的发病机制，从而推动有效疗法的开发。当前的目标应用是为了了解铁对 IPF 发病机制的贡献及其潜在机制重点关注铁介导的肺成纤维细胞激活。有证据表明铁在肺部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。我们的初步研究确定了铁出口基因溶质载体家族 40 成员 1 (SLC40A1) 作为肺成纤维细胞铁积累的关键基因。我们还鉴定了两个新的铁调节基因，即含有 SH3 结构域的无名指 1 (SH3RF1)、E3 泛素蛋白连接酶和同源结构域相互作用蛋白激酶 2 (HIPK2)，一种共转录调节因子提供了这两个基因调节肺成纤维细胞活化的证据。根据我们的初步研究，我们总体假设是，由于 SLC40A1 减少，肺成纤维细胞中铁水平升高，导致通过下调 SH3RF1 表达和上调 HIPK2 激活肺成纤维细胞表达。该假设将通过使用原代人肺的体外研究组合进行检验使用药理学和遗传学研究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。目标 I 将确定铁通过 SLC40A1 在肺成纤维细胞中积累的机制以及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。目标 II 将定义铁激活肺的机制使用基因操作、免疫共沉淀、泛素化和分子信号转导通过 HIPK2 成纤维细胞路径分析。目标 III 将在两项临床前试验中确定铁和 HIPK2 对肺纤维化的体内影响使用成纤维细胞特异性基因缺失建立博来霉素和石棉诱导的肺纤维化小鼠模型 Hipk2 和药理学抑制剂。拟议的研究将建立铁的分子机制肺成纤维细胞中的积累以及 SH3RF1 和 HIPK2 在肺成纤维细胞激活中的新作用。