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

• 批准号: 9325868
• 负责人: Bryan D Maliken
• 金额: $ 4.65万
• 依托单位: CINCINNATI CHILDRENS HOSP MED CTR
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-09-30 至 2021-09-29
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9325868
• 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; 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; 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

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.

项目摘要 缺血性心脏病是世界范围内死亡的主要原因。为了应对这一重大公共卫生流行病， 已经出现了两个流行的研究领域：1）旨在递送培养扩增的多能细胞的细胞疗法， 细胞，和2）内源性心脏祖细胞（CPC） 以及它们在心肌的体内更新和再生中的潜在作用。最初，这两个主题似乎 这是不可分割的联系，但现在越来越清楚的是，虽然用于治疗的CPC的递送可以提供一些 机械上无法解释的益处，这些细胞保留在心肌中是边缘性的和新生的。 心肌细胞分化更不常见。一群假定的CPC，以酪氨酸激酶为标志， 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一个基因谱系 示踪模型证明了Kit谱系在心脏中的心脏贡献， Kit衍生的细胞很少成为心肌细胞，但具有形成血管内皮细胞的高倾向。 内皮细胞此外，这项研究表明，大约80%的Kit谱系示踪心肌细胞 实际上是来自融合事件，而所寻求的新生心肌细胞甚至比 最初相信。为了验证这项研究，我们的目标是消除Kit衍生细胞产生任何凋亡的能力， 通过敲除必需的心肌转录因子Gata 4，从理论上允许 仅用于源自融合的谱系示踪心肌细胞。有趣的是，基特血统的出现 由于融合引起的心肌细胞数量随着Kit谱系中Gata 4的丢失而显著增加，此外， 我们观察到心脏中Kit谱系细胞和总心脏血管内皮细胞的显著增加。 我们现在假设，将这些发现结合起来的是Gata 4在成人血管内皮中的新作用， 最初似乎是心肌细胞先天融合特性的一个有趣驱动因素， 可能是由于增加的血管渗透性和新血管生成引起的偶然读出。虽然许多加塔 转录因子在血管发育中的作用，包括Gata 4，很少有研究 一直专注于成人血管内稳态的研究更好地理解这种Gata 4介导的转录控制 血管扩张可以提供有意义的洞察心脏更新和修复的机制。到 为了解决Gata 4在心脏血管内皮中的这种新作用，我们将追求以下目标：（1） 确定Gata 4的内皮特异性损失是否导致血管通透性增加和增强 （2）评估在成人心脏内皮中Gata 4缺失后心脏恢复的变化。