Targeting myofibroblast activation in chronic fibrotic disease

靶向慢性纤维化疾病中的肌成纤维细胞激活

• 批准号: 7741692
• 负责人: ARTHUR ROGER STRAUCH
• 金额: $ 37.5万
• 依托单位: OHIO STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-12-05 至 2011-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7741692
• 关键词: 1-Phosphatidylinositol 3-Kinase; Affect; Animal Model; Attenuated; Biochemical; Biochemical Pathway; Biology; COL1A2 gene; Cardiac; Cardiac Myocytes; Cell Line; Cell Nucleus; Cells; Cessation of life; Chronic; Chronic Disease; Cicatrix; Collagen; Collagen Gene; Complex; Complication; Connective Tissue Cells; Contractile Proteins; DNA; DNA binding protein B; Deformity; Deposition; Diagnosis; Disease; Dominant-Negative Mutation; Endothelin-1; Feedback; Fibroblasts; Fibrosis; Gene Expression; Gene Expression Regulation; Genetic Transcription; Growth Factor; Heart; Hypertrophic Cicatrix; In Vitro; Individual; Interleukin-13; Intervention; Lung; Manuscripts; Mediating; Messenger RNA; Modeling; Molecular; Mus; Muscle Cells; Myofibroblast; Nuclear; Operative Surgical Procedures; Outcome; Output; Peptides; Pharmacotherapy; Phosphotransferases; Play; Principal Investigator; Process; Property; Proteins; Published Comment; Publishing; Pulmonary Heart Disease; Pur-1 protein; Quality of life; RNA-Binding Proteins; Reading; Receptor Signaling; Regulation; Reperfusion Injury; Repressor Proteins; Research; Role; Signal Transduction; Staging; Structure of parenchyma of lung; Therapeutic; Thrombin; Time; Tissues; Transcription Coactivator; Transcription Regulatory Protein; Translations; Transplant Recipients; Vascular Smooth Muscle; Werdnig-Hoffmann Disease; Wound Healing; alpha Actin; autocrine; base; cell type; cytokine; design; improved; in vivo; inhibitor/antagonist; interstitial; interstitial cell; loss of function; novel; open wound; polypeptide; programs; promoter; research study; small hairpin RNA; small molecule

DESCRIPTION (provided by applicant): Chronic accumulation of myofibroblasts in healing wounds is associated with hypercontractility, excessive deposition of interstitial collagens, and destructive tissue remodeling. Vascular smooth muscle alpha-actin (SMalphaA) is a contractile protein transiently expressed by differentiated myofibroblasts for generating tensile force required to close open wounds. In chronic fibrotic disease, myofibroblast differentiation is dysfunctional and we discovered that molecular signaling required for activation of both the SMaA and type I collagen genes in these cells also provides negative feedback that could potentially limit the recruitment of hyperactive myofibroblasts during wound healing and destructive remodeling. Studies outlined in this proposal are expected to reveal novel forms of functional interplay of the DNA- and mRNA-binding proteins YB-1, Pur alpha, and Pur beta with the SMalphaA and type I collagen promoters and clarify how these proteins are affected by pro-fibrotic agents such as TGFbeta1 and thrombin that, if unchecked, may cause myofibroblast progression to hypertrophic scarring. Experiments are designed to initiate, amplify, or attenuate myofibroblast differentiation to better understand strategies for controlling SMalphaA and type I collagen gene output at the transcriptional and translation levels as well as reveal novel interventional strategies that might be useful for minimizing aberrant wound healing outcomes. Aim 1 will examine TGFbeta1-regulated interaction of YB-1 and Pur protein repressors with SMalphaA and collagen promoter DNA and the transcriptional activators Sp1, SRF, and Smads 2,3, delineate regions of repressor polypeptide chains required for this functional interplay, and attempt to disrupt complex formation and disable pathobiologic myofibroblast differentiation using peptide decoys and small molecule pharmacologic inhibitors. Aim 2 will determine if thrombin potentiates myofibroblast differentiation at the level of translational control thus functioning as a TGFbeta1 supplement or instead antagonizes this growth factor by blocking transcription and myofibroblast recruitment by inducing the anti-fibrotic transcriptional regulatory protein, Egr-1. Aim 3 studies will explore alternative, Smad-independent mechanisms of myofibroblast differentiation and fibrosis. Loss-of-function approaches based on pharmacologic inhibition of TGFbeta1/Smad kinase- or phosphatidylinositol-3-kinase (PI3K)/Akt kinase signaling will be used to evaluate their possible suppressive effect on myofibroblast activation in vitro and cardiac fibrosis in mice after ischemia/reperfusion injury. The ability of TGFbeta1 and thrombin to exploit the unique DNA-, RNA-, and protein-binding properties of YB-1 and Pur proteins adds a new dynamic perspective to control of gene expression during myofibroblast differentiation that may reveal optimum strategies for therapeutic management of chronic fibrotic diseases.

描述（由申请方提供）：愈合伤口中肌成纤维细胞的慢性蓄积与过度收缩、间质胶原过度沉积和破坏性组织重塑相关。血管平滑肌α-肌动蛋白（SMalphaA）是一种由分化的肌成纤维细胞瞬时表达的收缩蛋白， 闭合开放性伤口所需的力量。在慢性纤维化疾病中，肌成纤维细胞分化功能障碍 我们发现激活SMaA和I型胶原基因所需的分子信号 在这些细胞中也提供了负反馈，可能会限制招募过度活跃的 肌成纤维细胞在伤口愈合和破坏性重塑期间。本提案中概述的研究包括 有望揭示DNA和mRNA结合蛋白YB-1，Pur α， 和Pur β与SMalphaA和I型胶原启动子的关系，并阐明这些蛋白质如何受到促纤维化的影响。 因子如TGF β 1和凝血酶，如果不加检查，可能导致肌成纤维细胞进展为 增生性疤痕设计实验以启动、扩增或减弱肌成纤维细胞分化， 更好地理解控制SMalphaA和I型胶原蛋白基因在转录水平输出的策略， 翻译水平，并揭示了新的干预策略，可能有助于最大限度地减少异常 伤口愈合结果。目的1将研究TGF β 1调节的YB-1和Pur蛋白阻遏物的相互作用 与SMalphaA和胶原启动子DNA以及转录激活因子Sp1、SRF和Smads 2，3一起， 这种功能相互作用所需的阻遏物多肽链的区域，并试图破坏复合物 使用肽诱饵和小分子形成并使病理生物学肌成纤维细胞分化失活 药理学抑制剂。目的2将确定凝血酶是否在一定水平上增强肌成纤维细胞分化 因此作为TGF β 1补充剂起作用，或者相反通过以下方式拮抗这种生长因子： 通过诱导抗纤维化转录调节因子阻断转录和肌成纤维细胞募集， 蛋白质，Egr-1。目的3研究将探索肌成纤维细胞的替代性、非Smad依赖性机制， 分化和纤维化。基于TGF β 1/Smad药理学抑制的功能丧失方法 激酶或磷脂酰肌醇-3-激酶（PI 3 K）/Akt激酶信号传导将用于评估它们可能的 对心肌缺血再灌注后成肌纤维细胞活化及心肌纤维化抑制作用 损伤TGF β 1和凝血酶利用TGF β 1独特的DNA、RNA和蛋白质结合特性的能力， YB-1和Pur蛋白为肌成纤维细胞中基因表达的调控提供了新的动态视角 分化，可能揭示慢性纤维化疾病的治疗管理的最佳策略。