Investigating pulmonary complications due to abnormal collagen/ER stress in Osteogenesis Imperfecta

研究成骨不全症中胶原蛋白/内质网应激异常引起的肺部并发症

基本信息

批准号：
10556308
负责人：
Jennifer Zieba
金额：
$ 39万
依托单位：
UNIVERSITY OF CALIFORNIA LOS ANGELES
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：
2023-02-15 至 2028-01-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10556308
关键词：
Address Affect Apoptosis Basement membrane Bleomycin Bone Diseases Cell Communication Cell Differentiation process Cell physiology Cell secretion Cells Chronic Clinical Coculture Techniques Collagen Collagen Gene Collagen Type I Communication Defect Deformity Development Disease Environment Epithelial Cells Exhibits Extracellular Matrix Fibroblasts Foundations Fracture Frequencies Functional disorder Future Gene Expression Gene Expression Profile Genes Histologic Homeostasis Impairment In Vitro Infection Knowledge Lead Lung Lung diseases Mesenchymal Methodology Methods Modeling Molecular Molecular Chaperones Morbidity - disease rate Morphology Mus Mutation Myofibroblast Organoids Osteoblasts Osteogenesis Imperfecta Patients Perinatal mortality demographics Phenotype Population Population Distributions Predisposition Proliferating Proteins Pulmonary Valve Insufficiency RNA Reaction Recovery Reporting Severities Signal Pathway Signal Transduction Structure Structure of parenchyma of lung Therapeutic Tissues Validation Work alveolar epithelium bone bone fragility cell injury defined contribution disability endoplasmic reticulum stress environmental stressor experimental study improved in vivo insight loss of function mutation lung development lung injury mortality mouse model mutant novel postnatal postnatal development pulmonary function single-cell RNA sequencing skeletal

项目摘要

Project Summary Osteogenesis imperfecta (OI) is a genetically heterogenous disorder characterized by increased bone fragility leading to fractures and primarily results from defects in the structure and/or the amount of secreted type I collagen. While bone fragility is the primary cause of morbidity in OI, pulmonary compromise is the leading cause of mortality. We and others showed that in OI there is an abnormal bone extracellular matrix (ECM) structure and type I collagen expressing cells manifest ER stress. Pulmonary mesenchymal derived cells also abundantly express type I collagen. We hypothesize that OI negatively impacts the lung through two mechanisms; secretion of an abnormal ECM and chronic ER stress. Using two OI mouse models representing major forms of OI (missense/loss of function mutations in type I collagen), this proposal will address the hypotheses that mutant type I collagen secretion and ER stress produces abnormal pulmonary morphology, affects lung cell differentiation, impairs lung damage recovery, and that altered ECM and ER stress negatively impact signaling pathways. We address these hypotheses via three aims: 1. Determine the effect of type I collagen mutations on lung postnatal homeostasis and cell differentiation/communication. Hypothesis: Mutations in type I collagen genes lead to alterations in OI lung morphology and cell differentiation. Strategy: Using Aga2 and Col1a1+/- mouse models, the lung will be studied at multiple stages of development via histological/immunohistochemical (IHC) for differentiation and ECM composition. Using in vitro epithelial cell/fibroblast co-culture organoid experiments we will define the contribution of abnormal ECM secretion to lung cell differentiation, proliferation, and apoptosis. 2. Determine the effect of ER stress due to type I collagen mutations on lung cell differentiation, tissue homeostasis, and reaction to damage. Hypothesis: ER stress in pulmonary type I collagen expressing cells affect lung cell differentiation and function. Strategy: Using the models from Aim 1, we will determine ER stress levels in pulmonary cells and whether modulating ER stress in vivo with the chaperone 4-PBA can influence cell differentiation and homeostasis. Using organoid experiments, we will define the contribution of chronic ER stress to lung cell differentiation, proliferation, and apoptosis. To study OI lung damage susceptibility, we will perform in vivo treatment of WT, Aga2, and Col1a1+/- mice with bleomycin to observe the effects of cellular damage on OI lung tissue in conjunction with the 4-PBA treatment; 3. Identify changes in lung cell population distribution and gene expression in the context of an abnormal ECM and ER stress. Hypothesis: Lungs with altered ECM and ER stress affect signaling pathways important in cell differentiation and function. Strategy: Using the Aga2 and Col1a1+/- mouse models, single-cell RNA-seq cells/tissues derived from lung will be performed to identify changes in cell development and gene expression correlated with signaling cascades localized to specific lung cell populations. Completion of these aims will reveal causative mechanisms while introducing novel treatment methods of OI pulmonary dysfunction, the major cause of mortality in OI.

项目摘要成骨不完美（OI）是一种遗传异源性疾病，其特征是骨骼脆弱性增加导致裂缝，主要是由于结构和/或分泌I型的缺陷而导致的胶原。虽然骨骼脆弱性是OI发病率的主要原因，但肺部折衷是主要原因死亡率。我们和其他人表明，在OI中有异常的骨外基质（ECM）结构和I型胶原蛋白表达细胞表现出ER应激。肺间充质衍生细胞也很多 Express I型胶原蛋白。我们假设OI通过两种机制对肺部产生负面影响。分泌 ECM异常和慢性ER应激。使用代表OI的主要形式的两个OI鼠标模型（I型胶原蛋白中的错义/功能突变丧失），该提案将解决突变体的假设 I型胶原蛋白分泌和ER应力产生异常的肺形态，影响肺部细胞分化，损害肺损伤恢复，并改变ECM和ER应力对信号产生负面影响途径。我们通过三个目标解决这些假设：1。确定I型胶原突变对肺产后稳态和细胞分化/通信。假设：I型胶原蛋白中的突变基因导致OI肺形态和细胞分化的改变。策略：使用AGA2和COL1A1 +/- 小鼠模型，将通过组织学/免疫组织化学研究肺部的多个发育阶段（IHC）用于分化和ECM组成。使用体外上皮细胞/成纤维细胞共培养器官实验我们将定义ECM分泌异常对肺细胞分化，增殖，，和凋亡。 2。确定因I型胶原突变对肺细胞分化而引起的ER应力的影响，组织稳态，对损伤的反应。假设：I型I胶原蛋白表达的ER应力细胞影响肺部细胞分化和功能。策略：使用AIM 1的模型，我们将确定ER 肺细胞中的应力水平以及与伴侣4-PBA体内的ER应力是否可以影响细胞分化和稳态。使用类器官实验，我们将定义慢性ER应力对肺细胞分化，增殖和凋亡。为了研究肺损伤易感性，我们将在体内对WT，AGA2和COL1A1 +/-小鼠的体内治疗，以观察细胞的影响与4-PBA治疗结合使用OI肺组织的损害； 3。确定肺部细胞种群的变化在异常的ECM和ER应激的背景下的分布和基因表达。假设：肺 ECM和ER应力的改变会影响信号通路在细胞分化和功能中很重要。战略：使用AGA2和COL1A1 +/-小鼠模型，衍生自肺的单细胞RNA-seq细胞/组织将是进行的以确定细胞发育和基因表达的变化与信号级联有关位于特定的肺部细胞群体。这些目的的完成将揭示原因机制引入了OI肺功能障碍的新型治疗方法，这是OI死亡率的主要原因。