Extracellular matrix regulation of cellular crosstalk in cardiac fibrosis

心脏纤维化中细胞串扰的细胞外基质调节

基本信息

批准号：
10634954
负责人：
ALEXIS R. DEMONBREUN
金额：
$ 70.7万
依托单位：
NORTHWESTERN UNIVERSITY AT CHICAGO
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：
2023-04-01 至 2027-03-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10634954
关键词：
Alleles Amino Acids Antibodies Arrhythmia Binding Binding Proteins Cardiac Cardiac Myocytes Cardiomyopathies Cells Chronic Chronic Disease Cicatrix Communication Deposition Differentiation and Growth Disease Progression Extracellular Matrix Extracellular Matrix Proteins Family Fibroblasts Fibrosis Genes Genetic Genotype Goals Haplotypes Heart Heart Diseases Heart Injuries Human Human Engineering Impairment Injury Link Mechanics Mediating Modeling Mouse Strains Mus Muscular Dystrophies Myocardial dysfunction Pathogenesis Pattern Positioning Attribute Predisposition Proliferating Proteins Proteolysis Regulation Resistance Risk Role Sarcolemma Signal Transduction Skeletal Muscle Surface Testing Therapeutic Tissues Transforming Growth Factor beta Work cardiac tissue engineering cardioprotection cell growth cell growth regulation cell type coronary fibrosis heart function heart rhythm improved in vivo in vivo Model induced pluripotent stem cell derived cardiomyocytes injured migration novel risk variant scaffold transcriptome

项目摘要

Abstract: Cardiac fibrosis impairs heart function and increases risk for cardiac arrhythmias. The transforming growth factor beta (TGFβ) family is major driver of fibrosis, including cardiac fibrosis. Latent TGFβ binding proteins (LTBPs) are extracellular matrix proteins that restrict latent TGFβ release and activity. We previously identified LTBP4 as a genetic modifier of muscular dystrophy, where we showed that LTBP4’s ability to bind TGFβ was strongly linked to sarcolemmal stability and fibrosis. LTBP4 is found along the exterior surface of the sarcolemma in myofibers, and LTBP4 is similarly found on the exterior surface of cardiomyocytes in a striated pattern. Because LTBP4 is highly expressed in the heart, LTBP4 is well positioned to regulate latent TGFβ release in cardiac fibrosis. The LTBP4 genes in mice and humans have naturally occurring protective and deleterious forms which produce proteins associated with differential TGFβ activity and downstream TGFβ signaling. Mouse strains bearing the protective Ltbp4 allele have 12 amino acids inserted into LTBP4’s hinge region, rendering the protein more resistant to proteolysis and latent TGFβ release. Correspondingly, mouse strains harboring the deleterious allele of Ltbp4, lacking 12 amino acids, produce an LTBP4 protein that is more susceptible to proteolysis leading to excess latent TGFβ release, signaling and fibrosis. In chronic progressive cardiomyopathies, there is dysregulation of matrix remodeling, which can further enhance maladaptive matrix shifts and adversely alter heart function and promote arrhythmia risk. We will now study LTBP4 in the heart by probing TGFβ’s interaction with LTBP4 using three approaches. In Aim 1, we will use decellularized matrices, called dECMs, from mouse hearts to define components and activity necessary for cellular communication between cardiomyocytes and cardiac fibroblasts. In Aim 2, we will evaluate human induced pluripotent stem cell-derived cardiomyocytes, and we will also conduct in vivo assessment of blocking TGFβ release in mice using an anti-LTBP4 antibody to promote cardiac sarcolemmal stability and reduce cardiac fibrosis. In Aim 3, we will evaluate cellular crosstalk mediated by LTBP4 in human engineered heart tissues (EHTs). Through this work, we will expand the mechanistic understanding of LTBP’s regulation of TGFβ with the goal of therapeutically modifying the matrix.

抽象的：心脏纤维化会损害心脏功能并增加心律失常的风险。生长因子 β (TGFβ) 家族是纤维化的主要驱动因素，包括潜在的 TGFβ 结合。蛋白 (LTBP) 是限制潜在 TGFβ 释放和活性的细胞外基质蛋白。确定 LTBP4 是肌营养不良症的遗传修饰剂，我们证明 LTBP4 能够结合 TGFβ 与肌膜稳定性密切相关，并且沿着肌膜的外表面发现了 LTBP4。 LTBP4 类似地存在于心肌细胞的外表面。由于 LTBP4 在心脏中高表达，因此 LTBP4 能够很好地调节潜伏期。心脏纤维化中的 TGFβ 释放 LTBP4 基因在小鼠和人类中具有天然的保护作用。以及产生与差异 TGFβ 活性和下游 TGFβ 相关的蛋白质的有害形式带有保护性 Ltbp4 等位基因的小鼠品系在 LTBP4 铰链中插入了 12 个氨基酸。区域，使蛋白质对蛋白水解和潜在的 TGFβ 释放具有更强的抵抗力。含有 Ltbp4 有害等位基因（缺乏 12 个氨基酸）的菌株产生的 LTBP4 蛋白是更容易受到蛋白水解作用，导致潜在的 TGFβ 过度释放、信号转导和慢性纤维化。进行性心肌病，存在基质重塑失调，这可以进一步增强适应不良的基质变化会对心脏功能产生不利影响并增加心律失常的风险。通过使用三种方法探测 TGFβ 与 LTBP4 的相互作用来研究心脏中的 LTBP4。脱细胞基质，称为 dECM，来自小鼠心脏，用于定义必要的成分和活性在目标 2 中，我们将评估人类心肌细胞和心脏成纤维细胞之间的细胞通讯。诱导多能干细胞来源的心肌细胞，我们还将进行体内阻断评估使用抗 LTBP4 抗体释放小鼠体内的 TGFβ，以促进心脏肌膜稳定性并减少在目标 3 中，我们将评估人类工程心脏中 LTBP4 介导的细胞串扰。通过这项工作，我们将扩大对 LTBP 调节的机制的理解。 TGFβ 的目的是治疗性地改变基质。