Cardiovascular Impact of Gata4 Loss in the c-Kit Lineage

c-Kit 谱系中 Gata4 缺失对心血管的影响

基本信息

批准号：
9768527
负责人：
Bryan D Maliken
金额：
$ 3.78万
依托单位：
CINCINNATI CHILDRENS HOSP MED CTR
依托单位国家：
美国
项目类别：
财政年份：
2017
资助国家：
美国
起止时间：
2017-09-30 至 2020-05-23
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9768527
关键词：
Address Adult Apoptosis Appearance Area Autologous Blood Vessels Bone Marrow Bone Marrow Transplantation Cardiac Cardiac Myocytes Cardiovascular system Cause of Death Cell Lineage Cell Therapy Cell Transplantation Cell Transplants Cells Cicatrix Clinical Clinical Trials Coronary Coronary artery Development Echocardiography Endothelial Cells Endothelium Enterobacteria phage P1 Cre recombinase Epidemic Evaluation Event Flow Cytometry GATA4 gene Gene Expression Generations Genetic Goals Heart Heart Injuries Homeostasis Human Immunofluorescence Immunologic In Vitro Incentives Individual Infarction Infiltration Infusion procedures Injury Investigation Ischemia Knock-in Mouse Knock-out Link Mediating Modeling Monitor Mus Myocardial Myocardial Infarction Myocardial Ischemia Myocardium Natural regeneration Physiological Population Prevention Proto-Oncogene Protein c-kit Public Health Publishing Receptor Protein-Tyrosine Kinases Recovery Reperfusion Injury Reperfusion Therapy Reporting Research Personnel Role Site Source Stem cells Supporting Cell Therapeutic Time Transcriptional Regulation Tube Vascular Endothelium Vascular Permeabilities Vascularization Vision Work angiogenesis artery infusion bone cardiac regeneration cardiac repair experimental study functional improvement global health heart dimension/size heart function improved in vivo insight migration neovascularization new therapeutic target novel prophylactic regenerative repaired stem transcription factor

项目摘要

Project Summary Ischemic heart disease is the leading cause of death worldwide. To approach this major public health epidemic, two prevailing areas of study have emerged: 1) Cell therapy aimed at delivering culture-expanded pluripotent cells by coronary artery infusion after an ischemic event, and 2) Endogenous cardiac progenitor cells (CPCs) and their potential role for in vivo renewal and regeneration of the myocardium. Initially these two topics seemed inextricably linked, but it is now becoming clear that while delivery of CPCs for therapy may provide some mechanistically-unexplained benefit, the retention of these cells into the myocardium is marginal and de novo cardiomyocyte differentiation is even less common. A population of putative CPCs, marked by the tyrosine kinase receptor, c-Kit, have been a common focus in both areas of study. Our lab recently published a genetic lineage tracing model demonstrating the cardiac contribution of the Kit lineage in the heart which showed conclusively that Kit-derived cells rarely become cardiomyocytes, but have a high propensity for the formation of vascular endothelium. Furthermore, this study demonstrated that approximately 80% of Kit lineage-traced cardiomyocytes were actually derived from fusion events and the sought-after de novo cardiomyocyte was even more rare than originally believed. To validate this study, we aimed to eliminate the ability of Kit-derived cells to make any de novo cardiomyocytes by knocking out essential cardiomyogenic transcription factor, Gata4, theoretically allowing only for lineage-traced cardiomyocytes derived from fusion. Interestingly, the appearance of Kit lineage-traced cardiomyocytes due to fusion increased dramatically with the loss of Gata4 in the Kit lineage, and, furthermore, we observed a dramatic increase of both Kit-lineage cells in the heart and total cardiac vascular endothelium. We now hypothesize that what is uniting these findings is a novel role for Gata4 in the adult vascular endothelium, and what initially appeared to be an interesting driver of innate fusigenic character with cardiomyocytes is most likely an incidental readout due to increased vascular permeability and neoangiogenesis. While many GATA transcription factors have had previously reported roles in vascular development, including Gata4, few studies have focused on adult vascular homeostasis. Better understanding of this Gata4-mediated transcriptional control of vascular expansion could provide meaningful insight into mechanisms of cardiac renewal and repair. To address this novel role of Gata4 in the cardiac vascular endothelium, we will pursue the following aims: (1) Determine whether endothelial-specific loss of Gata4 leads to increased vascular permeability and enhanced angiogenesis; (2) Assess changes in cardiac recovery after deletion of Gata4 in the adult cardiac endothelium.

项目概要缺血性心脏病是全世界死亡的主要原因。为应对这一重大公共卫生流行病，两个流行的研究领域已经出现：1）细胞疗法旨在提供培养扩增的多能性缺血事件后通过冠状动脉输注的细胞，以及 2) 内源性心脏祖细胞 (CPC) 及其对心肌体内更新和再生的潜在作用。最初这两个主题似乎密不可分地联系在一起，但现在越来越清楚的是，虽然递送 CPC 进行治疗可能会提供一些机械上无法解释的益处，这些细胞保留到心肌中的程度是微乎其微的，而且是从头开始的心肌细胞分化更不常见。由酪氨酸激酶标记的假定 CPC 群体受体 c-Kit 一直是这两个研究领域的共同焦点。我们的实验室最近发表了遗传谱系追踪模型展示了 Kit 谱系对心脏的贡献，这最终表明 Kit衍生的细胞很少成为心肌细胞，但具有高度形成血管的倾向内皮细胞。此外，这项研究表明，大约 80% 的 Kit 谱系追踪心肌细胞实际上源自融合事件，而广受欢迎的新生心肌细胞甚至比原本相信。为了验证这项研究，我们的目标是消除 Kit 衍生细胞进行任何 de 的能力。通过敲除必需的心肌生成转录因子 Gata4，理论上可以实现新生心肌细胞仅适用于融合衍生的谱系追踪心肌细胞。有趣的是，Kit的出现是有谱系的随着 Kit 谱系中 Gata4 的缺失，融合引起的心肌细胞急剧增加，而且，我们观察到心脏中的 Kit 谱系细胞和总心脏血管内皮细胞显着增加。我们现在假设，将这些发现结合起来的是 Gata4 在成人血管内皮细胞中的新作用，最初似乎是心肌细胞先天融合特征的一个有趣的驱动因素是可能是由于血管通透性增加和新血管生成导致的偶然读数。虽然很多GATA 先前报道过转录因子在血管发育中的作用，包括Gata4，但研究很少专注于成人血管稳态。更好地理解 Gata4 介导的转录控制血管扩张的研究可以为心脏更新和修复机制提供有意义的见解。到为了解决 Gata4 在心脏血管内皮细胞中的这一新作用，我们将追求以下目标：(1) 确定 Gata4 的内皮特异性缺失是否会导致血管通透性增加并增强血管生成； (2)评估成人心脏内皮细胞中Gata4缺失后心脏恢复的变化。