Mechanisms for Stem Cell Differentiation into Cardiac Myocytes

干细胞分化为心肌细胞的机制

基本信息

批准号：
7661180
负责人：
Margaret Loewy Kirby
金额：
$ 64.88万
依托单位：
DUKE UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2009
资助国家：
美国
起止时间：
2009-07-15 至 2011-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7661180
关键词：
Action Potentials Adult Binding Calcium Calmodulin Cardiac Cardiac Myocytes Cell Nucleus Cell fusion Cells Clinical Trials Coculture Techniques Collaborations Communication Connexin 43 Contracts Coupling Cytoplasm DsRed Environment Epigenetic Process Equipment Event Figs - dietary Gap Junctions Gene Expression Gene Proteins Genes Grant Hand Heart Heart failure Human ITPR1 gene In Vitro Inositol Lymphoid Cell Mediating Mesenchymal Stem Cells Methods Modeling Monitor Mus Myocardium Neonatal Neurons North Carolina Nuclear Nuclear Envelope Patients Phenotype Process Property Protein Isoforms Publishing Reagent Research Personnel Role Route Sarcomeres Severities Shapes Signal Transduction Skeletal Muscle Small Interfering RNA Stem cells Structural Protein Testing To specify Transcription Coactivator Translating United States United States National Institutes of Health Universities Up-Regulation Work base cell dimension embryonic stem cell gene therapy in vivo inhibitor/antagonist insight knock-down overexpression programs prototype public health relevance receptor stem cell differentiation stem cell therapy transcription factor

项目摘要

DESCRIPTION (provided by applicant): Five million patients suffer from heart failure in the United States. Clinical trials of stem cell therapy, initiated because of the severity of this problem, have yielded modest results. Understanding the epigenetic programs that induce differentiation of a naive somatic adult-derived stem cell into a cardiomyocyte is an important step in developing stem cell therapy. Our application tests components of this epigenetic process in human mesenchymal stem cells (hMSCells), because of their potential use in clinical trials and the ability to generate them from the patient. The proposed studies are based on our ongoing successful collaboration between investigators at Duke University, University of North Carolina at Chapel Hill, and East Carolina University. This collaboration has led to our General Hypothesis: Nuclear Ca2+ oscillations induce hMSCells to differentiate into cardiomyocytes. More specifically, shared cytosolic conduits, gap junctions, between adult-derived stem cells and adjacent contracting cardiomyocytes provide the route by which a signal from the cardiomyocyte enters the stem cell. This signal is translated into de novo nuclear Ca2+ oscillations in the stem cell and activation of a cardiac gene program. We propose that the following sequential events drive naive stem cell differentiation into a cardiomyocyte: shared functional connexin 43 (Cx43)-derived gap junctions develop between the stem cell and an adjacent contracting cardiomyocyte (Cx43 is the dominant isoform in cardiomyocytes and hMSCells); de novo Ca2+ oscillations develop in the stem cell cytoplasm ([Ca2+]c) and nucleus ([Ca2+]n) that are synchronous with the cardiomyocyte cytosolic calcium ([Ca2+]i) transients. The [Ca2+]n oscillations are mediated by inositol trisphosphate receptor 1 (the hMSCell nuclear envelope IP3R is IP3R1); the expression of Ca2+- signaling dependent effectors, CaMKIV and the newly described regulator of cardiac gene expression, calmodulin binding transcription factor (CAMTA1), and cardiac genes become up-regulated and the stem cell acquires a cardiomyocyte phenotype. We will use in vitro and in vivo studies to test our hypothesis. PUBLIC HEALTH RELEVANCE: In the proposal, we attempt to understand the epigenetic basis underlying the process that induces a naive somatic adult-derived stem cell to differentiate into a cardiomyocyte. Our general hypothesis is nuclear Ca2+ oscillations induce hMSCells to differentiate into cardiomyocytes. We study this in co-cultures with neonatal cardiomyocytes in vitro and in vivo in the mouse heart.

描述（由申请人提供）：500万患者在美国患心力衰竭。由于此问题的严重程度，启动的干细胞疗法的临床试验产生了适度的结果。了解将天真的躯体成人衍生干细胞分化为心肌细胞的表观遗传学程序是开发干细胞疗法的重要一步。我们的应用测试在人间充质干细胞（HMSCELLS）中的这种表观遗传过程的组成部分，因为它们在临床试验中的潜在使用以及从患者中产生它们的能力。拟议的研究基于我们在杜克大学，北卡罗来纳大学教堂山和东卡罗来纳大学的调查人员之间的持续成功合作。这种合作导致了我们的一般假设：核CA2+振荡诱导HMSCELLS分化为心肌细胞。更具体地说，成人衍生的干细胞和邻近收缩的心肌细胞之间的共享胞质导管，间隙连接，提供了从心肌细胞进入干细胞信号的途径。该信号在干细胞中转化为从头核CA2+振荡和心脏基因程序的激活。我们提出，以下顺序事件将幼稚的干细胞分化为心肌细胞：共享功能性连接蛋白43（CX43）衍生的间隙连接在干细胞与邻近收缩的心肌细胞之间发展（CX43是心肌细胞和HMSCELLS中的主要同工型）；在干细胞细胞质（[Ca2+] C）和核（[Ca2+] N）中，从头CA2+振荡与心肌细胞胞质钙（[[CA2+] I）瞬变同步。 [Ca2+] N振荡是由肌醇三磷酸受体1介导的（HMSCELL核包膜IP3R是IP3R1）； CA2+ - 信号依赖性效应子，CAMKIV和新描述的心脏基因表达调节剂，钙调蛋白结合转录因子（CAMTA1）和心脏基因被上调，干细胞获得心肌细胞表型。我们将使用体外和体内研究来检验我们的假设。公共卫生相关性：在提案中，我们试图理解诱导幼稚的躯体成人衍生的干细胞分化为心肌细胞的过程的表观遗传基础。我们的一般假设是核CA2+振荡诱导HMSCELLS分化为心肌细胞。我们在体外和小鼠心脏的体内与新生儿心肌细胞的共同培养中研究了这一点。