Targeting Matrix Stiffness in Lung Fibrosis Associated with Aging

针对与衰老相关的肺纤维化的基质硬度

• 批准号: 9767855
• 负责人: YONG ZHOU
• 金额: $ 50.8万
• 依托单位: UNIVERSITY OF ALABAMA AT BIRMINGHAM
• 依托单位国家: 美国
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-09-01 至 2022-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9767855
• 关键词: Acetylation; Acids; Adult Respiratory Distress Syndrome; Advanced Glycosylation End Products; Affect; Aging; Animals; Apoptosis; Apoptotic; Bleomycin; Blood; CD95 Antigens; CX3CL1 gene; Cells; Cessation of life; Collagen; Collagen Fiber; Death Domain; Development; Diabetes Mellitus; Digestion; Double Minutes; Eating; Effector Cell; Elderly; Extracellular Matrix; Feedback; Fibrosis; Genes; Goals; Human; Impairment; Infiltration; Injury; Interstitial Collagenase; Lesion; Lung; Lung diseases; Mechanics; Mediating; Molecular; Mus; Myofibroblast; Oral Administration; Pathway interactions; Patients; Phagocytosis; Production; Pulmonary Fibrosis; Reporting; Repression; Resistance; Resolution; Risk Factors; Role; Signal Transduction; Slice; Solubility; Structure of parenchyma of lung; TP53 gene; Testing; Tissues; aged; chemokine; crosslink; effective therapy; glycation; idiopathic pulmonary fibrosis; immunogenic; inhibitor/antagonist; macrophage; mouse model; novel; novel therapeutic intervention; polyacrylamide hydrogels; programs; receptor; recruit; treatment strategy; Acetylation; Acids; Adult Respiratory Distress Syndrome; Advanced Glycosylation End Products; Affect; Aging; Animals; Apoptosis; Apoptotic; Bleomycin; Blood; CD95 Antigens; CX3CL1 gene; Cells; Cessation of life; Collagen; Collagen Fiber; Death Domain; Development; Diabetes Mellitus; Digestion; Double Minutes; Eating; Effector Cell; Elderly; Extracellular Matrix; Feedback; Fibrosis; Genes; Goals; Human; Impairment; Infiltration; Injury; Interstitial Collagenase; Lesion; Lung; Lung diseases; Mechanics; Mediating; Molecular; Mus; Myofibroblast; Oral Administration; Pathway interactions; Patients; Phagocytosis; Production; Pulmonary Fibrosis; Reporting; Repression; Resistance; Resolution; Risk Factors; Role; Signal Transduction; Slice; Solubility; Structure of parenchyma of lung; TP53 gene; Testing; Tissues; aged; chemokine; crosslink; effective therapy; glycation; idiopathic pulmonary fibrosis; immunogenic; inhibitor/antagonist; macrophage; mouse model; novel; novel therapeutic intervention; polyacrylamide hydrogels; programs; receptor; recruit; treatment strategy

Aging is associated with the development of nonresolving pulmonary fibrosis in both human and experimental animals. Stiffening of the extracellular matrix (ECM) is a prominent feature of lung fibrosis. Interactions between stiffened fibrotic ECM and effector cells of tissue fibrosis, known as myofibroblasts (MFBs), provide a feedforward mechanism that sustains/amplifies lung fibrosis. Targeting matrix stiffness to break the profibrotic feedback loop represents a promising strategy for treatment of persistent/progressive lung fibrosis. The current study aimed to test a proof-of-concept of matrix de-stiffening therapy against lung fibrosis associated with aging. Previous studies have shown that the formation of advanced glycation end-products (AGEs) accumulates with aging and occurs at an accelerated rate in lung fibrosis. The ECM, in particular collagen matrix, is highly susceptible to glycation due to its slow turnover rate. AGEs drives nonenzymatic crosslinking of collagen fibers. The formation of intra- and inter-molecular collagen crosslinks is a crucial factor that stiffens the ECM. In preliminary studies, we targeted AGE-mediated glycation crosslinking for matrix de-stiffening and potential anti-fibrotic therapy against aging-associated nonresolving lung fibrosis in a bleomycin injury-induced mouse model. We found that anti-AGE treatment reduces the amount of crosslinked lung collagens, decreases lung stiffness, and promotes the resolution of experimental lung fibrosis in aged mice. We identified mouse double minute 4 (MDM4), a major endogenous inhibitor of p53, as a matrix stiffness-regulated mechanosensitive molecule. Reducing matrix stiffness downregulates MDM4 expression, resulting in p53 de- repression/activation. Gain of p53 function sensitizes lung MFBs to apoptosis by upregulating Fas and induces immunogenic conversion of MFBs that release CX3CL1 chemokine to recruit macrophages and express Death Domain 1α (DD1α) engulfment receptor to facilitate macrophage-mediated phagocytosis of apoptotic MFBs. These findings suggest that matrix de-stiffening by targeting nonenzymatic AGE crosslinking activates a fibrosis resolution pathway. The central hypothesis of the current project is that matrix de-stiffening sensing by MDM4 promotes lung MFB clearance and the reversal of aging-associated nonresolving pulmonary fibrosis. Specific aims are: (1) determine the mechanisms by which matrix stiffness regulates MDM4 expression; (2) determine whether matrix stiffness sensing by MDM4 mediates the clearance of lung MFBs by activation of a p53-directed gene program involving Fas, CX3CL1 and DD1α; and (3) determine the role of mechanosensitive MDM4 in the fate decisions of lung MFBs and the reversal of aging-associated pulmonary fibrosis in mice. The proposed study will elucidate cellular and molecular mechanisms involved in the reversal of aging-associated lung fibrosis by targeting nonenzymatic AGE crosslinking. The hypothesis, if proven, will establish a proof-of- concept of matrix de-stiffening therapy against aging-associated nonresolving pulmonary fibrosis.

衰老与人类和实验性肺纤维化的发展有关 动物。细胞外基质（ECM）的僵硬是肺纤维化的重要特征。互动 在僵硬的纤维化ECM和组织纤维化的效应细胞之间，称为肌纤维细胞（MFB），提供了一个 自杀/放大肺纤维化的前馈机制。靶向基质刚度打破纤维化 反馈回路代表了治疗持续/进行性肺纤维化的有前途的策略。这 当前的研究旨在测试针对肺纤维化的基质去固化疗法的概念证明 随着衰老。先前的研究表明，高级糖基化终产（年龄）的形成 随着衰老而积聚，并以肺纤维化的加速速率发生。 ECM，特别是胶原蛋白 矩阵由于其缓慢的周转率而非常容易受到糖基化的影响。年龄驱动非酶联交联 胶原纤维。形成和分子间胶原蛋白交联的形成是至关重要的因素 ECM。在初步研究中，我们针对年龄介导的糖基化交联，用于矩阵去固化和 潜在的抗纤维化疗法，以抗老化相关的非分解肺纤维化，在博来霉素损伤引起的 鼠标模型。我们发现抗年龄治疗减少了交联的肺胶原蛋白的量 降低肺僵硬，并促进老年小鼠实验性肺纤维化的分辨率。我们确定了 小鼠双分钟4（MDM4）是p53的主要内源性抑制剂，作为基质刚度调节 机械敏感分子。降低基质刚度下调MDM4的表达，导致p53 de- 抑制/激活。通过上调FAS和影响 MFB的免疫原性转化释放CX3CL1趋化因子以募集巨噬细胞并表达死亡 结构域1α（DD1α）吞噬受体，以促进凋亡MFB的巨噬细胞介导的吞噬作用。 这些发现表明，通过靶向非酶年龄交联的矩阵去固化会激活A 纤维化分辨率途径。当前项目的核心假设是矩阵降低了敏感性 MDM4促进了肺MFB清除率，并反向与衰老相关的非分辨肺纤维化。 具体目的是：（1）确定基质刚度调节MDM4表达的机制； （2） 确定MDM4通过激活A介导肺MFB的清除的矩阵刚度是否介导 涉及FAS，CX3CL1和DD1α的p53定向基因程序； （3）确定机械敏感的作用 MDM4在肺MFB的脂肪决策中和小鼠衰老相关的肺纤维化的逆转。这 拟议的研究将阐明与衰老相关的逆转涉及的细胞和分子机制 通过靶向非酶年龄交联的肺纤维化。该假设（如果得到证明）将建立证明 针对衰老相关的非解析肺纤维化的基质去固化疗法的概念。