Dynamic Interaction Between Cardiac Fibroblasts, Myocytes and the ECM

描述（由申请人提供）：心脏的形成需要几种细胞类型的相互作用，包括肌细胞、成纤维细胞、平滑肌细胞和内皮细胞，以及细胞外基质（ECM）的成分。这些细胞和非细胞成分的组织对于响应成人的各种生理信号是必要的。心肌成纤维细胞与肌细胞和ECM的相互作用尚不清楚，这是拟议研究的主题。细胞成分的具体排列对化学、机械和电子信号的交流至关重要。三种不同的模型显示细胞数量、ECM含量和生理参数的变化，将用于检验在正常和适应情况下，肌细胞、成纤维细胞和ECM之间的相互作用对心脏生长和重塑的调节至关重要的假设。成纤维细胞和肌细胞之间的相互作用受机械和化学信号的调节，对心脏的正常形态和功能至关重要。解决这一假设的具体目标是：确定压力过载肥厚、il -6损失和骨膜蛋白损失对成纤维细胞-肌细胞相互作用的影响。将在体内和体外检测成纤维细胞与肌细胞和ECM的相互作用，以确定细胞数量是否随细胞因子（特别是IL-6）和骨膜蛋白表达的变化而变化。具体目标2。确定机械刺激如何影响肌细胞-成纤维细胞相互作用。利用独特的三维培养系统，机械信号和细胞因子刺激的影响将用于测量成纤维细胞增殖、凋亡、与肌细胞的相互作用和ECM表达。具体目标3。确定调节成纤维细胞和肌细胞相互作用的连接蛋白和ECM受体。这些研究将采用多种细胞和分子方法来检查正常新生儿生长过程中成纤维细胞与肌细胞和ECM的增殖、周转和相互作用，在骨膜素-/-小鼠和IL-6-/-小鼠中，压力过载肥厚和改变的心脏重塑，显示出改变的心脏生理和表型。此外，这些研究将利用三维培养系统显示体内样肌细胞-成纤维细胞- ecm表型。这些研究产生的数据将为心脏成纤维细胞及其与肌细胞的相互作用在心脏重塑调控中的作用提供重要的新信息，并为控制心脏重塑的不良影响提供新的治疗靶点。

DESCRIPTION (provided by applicant): Formation of the heart requires the interaction of several cell types including myocytes, fibroblasts, smooth muscle cells and endothelial cells, as well as the components of the extracellular matrix (ECM). Organization of these cellular and acellular components is necessary to respond to a variety of physiological signals in the adult. The interaction of cardiac fibroblasts with myocytes and the ECM is poorly understood and it is the main theme of the proposed studies. The specific arrangement the cellular components is critical for communication by chemical, mechanical and electrical signals. Three different models that show changes in cell number, ECM content and physiological parameters will be used to examine the hypothesis that interaction between myocytes, fibroblasts and the ECM is critical in the regulation of cardiac growth and remodeling during both normal and adaptive situations. The interaction between fibroblasts and myocytes, which is regulated by mechanical and chemical signals, is essential to the proper form and function of the heart. The specific aims that will address this hypothesis are: Specific Aim 1. Determine the effects of pressure overload hypertrophy, IL-6-loss and periostin-loss on fibroblast-myocyte interactions. The interactions of fibroblasts with myocytes and the ECM will be examined both in vivo and in vitro to determine if cell number varies with changes in the expression of cytokines (specifically IL-6) and periostin. Specific Aim 2. Determine how mechanical stimulation affects myocyte-fibroblast interactions. Using a unique 3-D culture system, the effects of mechanical signaling and cytokine stimulation will be used to measure fibroblast proliferation, apoptosis, interactions with myocytes and ECM expression. Specific Aim 3. Determine the junctional proteins and ECM receptors that regulate the interaction between fibroblasts and myocytes. These investigations will employ a variety of cellular and molecular approaches to examine cell characterization, proliferation, turnover and interaction of fibroblasts with myocytes and the ECM during normal neonatal growth, pressure overload hypertrophy and altered cardiac remodeling in periostin-/- mice and IL-6-/- mice, which display altered cardiac physiology and phenotype. Moreover, these studies will utilize a 3-D culture system that displays an in vivo-like myocyte-fibroblast-ECM phenotype. The data generated from these studies will lead to significant new information on the role of the cardiac fibroblast and its interactions with myocytes in the regulation of cardiac remodeling, as well as providing novel therapeutic targets to control the adverse affects of cardiac remodeling. PUBLIC HEALTH RELEVANCE: The proposed studies will examine the dynamic interaction between cardiac fibroblasts, myocytes and the extracellular matrix. Experimental approaches will be used to understand the chemical, mechanical and electrical signaling between these cell types and the ECM under normal growth and under pathophysiological conditions.