Resolution of inflammation in healing myocardial infarcts

缓解心肌梗塞中的炎症

基本信息

批准号：
10543996
负责人：
Nikolaos G Frangogiannis
金额：
$ 70.94万
依托单位：
ALBERT EINSTEIN COLLEGE OF MEDICINE
依托单位国家：
美国
项目类别：
财政年份：
2008
资助国家：
美国
起止时间：
2008-01-15 至 2025-12-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10543996
关键词：
Activins Acute Affect Anti-Inflammatory Agents Attenuated Binding Biological Assay Blood Vessels Bone Morphogenetic Proteins Cardiac Cardiac Myocytes Cells Characteristics Cicatrix Complex Cytokine Activation Data Development Differentiation and Growth Down-Regulation Endothelial Cells Event Family Fibroblasts Fibrosis Flow Cytometry Follistatin Functional disorder Geometry Growth Factor Heart failure Heterogeneity Hypertrophy Immune In Vitro Infarction Inflammation Inflammatory Response Integrins Ischemia Knockout Mice Ligand Binding Macrophage Mediating Molecular Myeloid Cells Myocardial Myocardial Infarction Myocardium Myofibroblast Pathway interactions Patients Pericytes Phagocytes Phenotype Play Property Protein Isoforms Proteomics Reactive Oxygen Species Regulation Reperfusion Therapy Resolution Role STAT6 gene Signal Transduction Stromal Cell-Derived Factor 1 TGF-beta type I receptor TGFB1 gene TGFBR2 gene TP53 gene Testing Time Transforming Growth Factor beta Transforming Growth Factor beta Receptors angiogenesis cardiac repair chemokine experimental study gain of function healing immune function in vitro Assay in vivo insight interstitial loss of function member morphogens mortality pharmacologic receptor recruit repair function repaired response restraint single nucleus RNA-sequencing single-cell RNA sequencing transcriptome sequencing transcriptomics transforming growth factor beta3

项目摘要

ABSTRACT: The members of the Transforming Growth Factor (TGF)-Beta superfamily (TGF-Betas, Bone Morphogenetic Proteins/BMPs, Growth differentiation factors/GDFs, activins, etc), play a central role in repair, remodeling and fibrosis of the infarcted heart. TGF-Betas signal through heterotetrameric complexes composed of two type II and two type I TGF-Beta receptors (TBetaRII and TBetaRI respectively). TBetaRI activation transduces signals through a family of intracellular effectors, the receptor-activated Smads (R-Smads: Smad1/2/3/5/8), or by stimulating non-Smad cascades. The profile of type 1 receptors activated by a specific TGF-Beta superfamily member determines which downstream signaling cascade will be activated. Traditional concepts suggest that the 3 TGF-Beta isoforms (TGF-Beta1, -Beta2 and -Beta3) signal through Smad2 or Smad3, whereas BMPs activate Smad1 and Smad5. Studies in endothelial cells have challenged this concept, suggesting that TGF-Betas may stimulate both Smad1 and Smad2/3 signaling, with the 2 pathways exerting antagonistic effects. We have previously demonstrated cell- specific actions of TGF-Beta/Smad3 signaling in myocardial infarction that contribute to myofibroblast activation, modulate cardiomyocyte survival and function, and regulate macrophage phagocytic activity, and anti-inflammatory transition. However, the role of the Smad1 cascade in repair, remodeling and fibrosis of the infarcted heart remains unknown, and the effects of Smad1 on phenotype and function of immune and reparative cells has not been investigated. Our proposal explores the role of Smad1 signaling in repair and remodeling of the infarcted heart. Our preliminary data show that Smad1 is activated predominantly in infarct myofibroblasts and macrophages, but also in border zone cardiomyocytes and in pericytes. In vitro, TGF-Beta isoforms potently activate Smad1 in cardiac reparative cells (macrophages and fibroblasts). In vivo, our cell-specific loss-of-function experiments, revealed unanticipated anti-fibrotic effects of Smad1 in myofibroblasts and showed that in myeloid cells, Smad1 regulates the angiogenic properties of macrophages. Accordingly, we will explore cell-specific actions of Smad1 in cardiac repair and we will dissect the molecular mechanisms of Smad1 effects in 4 specific aims: Specific aim 1: to investigate the role of Smad1 in regulation of fibroblast phenotype following MI and to explore the molecular basis for Smad1-mediated anti-fibrotic effects. RNA- seq analysis suggests that the antifibrotic effects of Smad1 may involve competition with Smad3 signaling, or interactions with STAT6 and p53 fibrogenic pathways. The role of these mechanisms will be investigated in vitro and in vivo. Specific aim 2: to study the role of macrophage Smad1 in repair and remodeling of the infarcted heart. Our preliminary data show that macrophage-specific Smad1 perturbs repair of the infarcted heart by restraining the angiogenic properties of macrophages through downregulation of the angiogenic chemokine CXCL12. We will explore the mechanisms for the angiogenesis-regulating actions of macrophage Smad1 in vitro and in vivo. Specific aim 3: to investigate the molecular basis for Smad1 vs Smad2/3 activation in fibroblasts and macrophages and to test the hypothesis that the TBetaRI profile may be a key determinant of the transcriptomic and functional heterogeneity of reparative cells. We will use flow cytometry and single nucleus RNA-seq in vivo, and cell biological assays in vitro, to study the role of specific TBetaRIs in regulation of the phenotype and functional properties of fibroblasts and macrophages. Specific aim 4: to study the role of the Smad1 pathway in cardiomyocytes and in pericytes in the infarcted and remodeling myocardium. The proposed studies will provide for the first time insights into the role of Smad1 in regulation of myocardial inflammation and fibrosis, will dissect the mechanisms for Smad1-mediated actions, and will explore the molecular basis for the functional and transcriptomic heterogeneity of immune and reparative cells in the infarcted myocardium.

抽象的：转化生长因子 (TGF)-Beta 超家族的成员（TGF-Betas、骨形态发生蛋白/BMP、生长分化因子/GDF、激活素等）在梗塞心脏的修复、重塑和纤维化。通过异四聚体的 TGF-β 信号由两种 II 型和两种 I 型 TGF-Beta 受体（分别为 TBetaRII 和 TBetaRI）组成的复合物。 TβRI 激活通过细胞内效应器家族（受体激活的 Smads）转导信号（R-Smad：Smad1/2/3/5/8），或通过刺激非 Smad 级联。 1 型受体概况由特定的 TGF-β 超家族成员激活决定了下游信号级联将被激活。传统概念认为 3 种 TGF-Beta 亚型（TGF-Beta1、-Beta2 和 -Beta3）信号通过 Smad2 或 Smad3，而 BMP 则激活 Smad1 和 Smad5。内皮细胞研究挑战了这一概念，表明 TGF-Beta 可能同时刺激 Smad1 和 Smad2/3 信号传导，这两种途径发挥拮抗作用。我们之前已经证明了细胞 TGF-Beta/Smad3 信号传导在心肌梗塞中对肌成纤维细胞的具体作用激活，调节心肌细胞的存活和功能，并调节巨噬细胞的吞噬活性，和抗炎转变。然而，Smad1 级联在修复、重塑和梗塞心脏纤维化的机制仍不清楚，Smad1 对心脏纤维化表型和功能的影响尚不清楚免疫和修复细胞尚未得到研究。我们的提案探讨了 Smad1 信号在神经细胞修复和重塑中的作用梗塞的心脏。我们的初步数据表明 Smad1 主要在梗塞中被激活肌成纤维细胞和巨噬细胞，而且也存在于边界区心肌细胞和周细胞中。体外， TGF-Beta 异构体可有效激活心脏修复细胞（巨噬细胞和成纤维细胞）中的 Smad1。在 vivo，我们的细胞特异性功能丧失实验揭示了 Smad1 意想不到的抗纤维化作用在肌成纤维细胞中，并表明在骨髓细胞中，Smad1 调节肌成纤维细胞的血管生成特性巨噬细胞。因此，我们将探索 Smad1 在心脏修复中的细胞特异性作用，并且我们将剖析 Smad1 作用的分子机制有 4 个具体目标：具体目标1：研究Smad1对成纤维细胞表型的调节作用 MI 后并探索 Smad1 介导的抗纤维化作用的分子基础。 RNA- seq分析表明Smad1的抗纤维化作用可能涉及与Smad3的竞争信号传导或与 STAT6 和 p53 纤维化途径的相互作用。这些机制的作用将进行体外和体内研究。具体目标2：研究巨噬细胞Smad1在巨噬细胞修复和重塑中的作用梗塞的心脏。我们的初步数据表明巨噬细胞特异性 Smad1 会干扰巨噬细胞的修复通过下调巨噬细胞的血管生成特性来抑制梗塞心脏血管生成趋化因子CXCL12。我们将探讨血管生成调节机制巨噬细胞 Smad1 的体外和体内作用。具体目标 3：研究 Smad1 与 Smad2/3 激活的分子基础成纤维细胞和巨噬细胞，并检验 TBetaRI 谱可能是关键的假设修复细胞转录组和功能异质性的决定因素。我们将使用体内流式细胞术和单核RNA-seq，以及体外细胞生物学测定，以研究其作用特定TBetaRIs在成纤维细胞表型和功能特性调节中的作用巨噬细胞。具体目标4：研究Smad1通路在心肌细胞和心肌细胞中的作用梗塞和重塑心肌中的周细胞。拟议的研究将首次深入了解 Smad1 在调节中的作用心肌炎症和纤维化，将剖析 Smad1 介导的作用机制，以及将探索免疫和转录组的功能和转录异质性的分子基础梗塞心肌中的修复细胞。