Connexin 43 gap junction dynamics in the diabetic heart

糖尿病心脏中的连接蛋白 43 间隙连接动态

• 批准号: 8220750
• 负责人: Joseph A. Palatinus
• 金额: $ 3.66万
• 依托单位: MEDICAL UNIVERSITY OF SOUTH CAROLINA
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-02-01 至 2014-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8220750
• 关键词: Accounting; Actin-Binding Protein; Affect; African American; Animal Model; Arrhythmia; Arterioloscleroses; Binding; Blood Glucose; Blood Pressure; Cardiac; Cardiomyopathies; Cardiovascular system; Cause of Death; Cessation of life; Complications of Diabetes Mellitus; Connexin 43; Connexins; Diabetes Mellitus; Disease; Down-Regulation; Dyes; Echocardiography; Electrocardiogram; Electron Microscopy; Energy Transfer; Exhibits; Functional disorder; Gap Junctions; General Population; Glucose; Health Care Costs; Heart; Heart Diseases; Hyperglycemia; Hypertension; Hypertrophic Cardiomyopathy; Immunoprecipitation; In Vitro; Injury; Lead; Life; Maps; Medical; Membrane; Metabolic Diseases; Molecular; Myocardial; Myocardial Ischemia; Optics; Pathologic; Peptides; Phosphorylation; Physiological; Population; Predisposition; Prevalence; Proteins; Rattus; Recovery; Risk; Rodent Model; Role; Severities; South Carolina; Streptozocin; Testing; Tight Junctions; United States; Universities; Ventricular Arrhythmia; Ventricular Dysfunction; Western Blotting; Work; base; cellular imaging; db/db mouse; design; diabetic; diabetic patient; in vitro Model; insight; new therapeutic target; protein crosslink; sudden cardiac death; tissue repair; voltage

SPACE PROVIDED. Diabetic patients exhibit an increased risk of fatal arrhythmias, decreased recovery after a myocardial insult, and a cardiomyopathy leading to ventricular dysfunction independent of arteriolosclerosis and hypertension. The mechanism leading to cardiac dysfunction is not known, however, recent studies have suggested involvement of cardiac gap junction remodeling. Zonula occludens-1 (ZO-1) binds Connexin 43 (Cx43), and this interaction is important for gapjunction remodeling. It is hypothesized that the interaction of these two proteins is a major contributor to the lethal downstream physiological consequences including ventricular dysfunction and arrhythmias in the diabetic heart. This hypothesis will be tested through the following aims: 1 A. Determine whether Cx43 gap junction size and cellular distribution are altered in the ventricle of rodent models of diabetes in a manner that correlates with changes in ZO-1 Cx43 binding. 1B. Determine the extent to which diastolic dysfunction and susceptibility to inducible arrhythmia correlate with changes in ZO-1 Cx43 binding in the ventricle of rodent models of diabetes. 2A. Determine the extent to which hyperglycemia induced changes in Cx43 gap junction size, cellular distribution, and phosphorylation correlate with ZO-1 binding Cx43 in vitro. 2B. Determine if hyperglycemia induced remodeling of Cx43 gap junctions are normalized by a membrane permanent peptide (ACT-1) designed to inhibit the interaction of ZO-1 with Cx43 in vitro. Several approaches will be used including immuno-confocal colocalization analysis, Western blotting, FRET (fluorescent resonance energy transfer), immunoprecipitation, protein-protein crosslinking, and electron microscopy. In addition cardiac function will be assessed using electrocardiography, echocardiography and optical mapping of fluorescent voltage sensitive dyes. Additionally in Aim 2, live cell imaging of fluorescently tagged constructs of Cx43 and ZO-1 in high and low glucose conditions will also be performed. Eighty percent of diabetics in the US die of cardiovascular complications resulting in over 50000 deaths/year. This project will provide a better understanding of the fundamental mechanism of diabetic heart disease and may lead to new treatments beyond blood pressure and sugar control.

提供的空间。 糖尿病患者表现出致命性心律不齐的风险增加，心肌侮辱后康复的恢复降低以及心肌病，导致心室功能障碍与无动脉粥样硬化和高血压无关。 导致心脏功能障碍的机制尚不清楚，但是，最近的研究表明心脏间隙连接重塑的参与。 Zonula occludens-1（ZO-1）结合了连接蛋白43（CX43），并且这种相互作用对于间隙重塑很重要。假设这两种蛋白质的相互作用是致命下游生理后果的主要原因，包括心室 糖尿病心脏的功能障碍和心律不齐。该假设将通过以下目的进行检验： 1 A.确定糖尿病啮齿动物模型的心室中CX43的间隙连接大小和细胞分布是否与ZO-1 CX43结合的变化相关的方式。 1B。确定与诱导性心律不齐相关的舒张功能障碍和易感性与糖尿病啮齿动物模型心室中ZO-1 CX43结合的变化相关的程度。 2a。确定高血糖在多大程度上诱导CX43间隙连接大小，细胞分布和磷酸化的变化与ZO-1结合CX43的体外程度。 2b。确定高血糖诱导的CX43间隙连接的重塑是否通过膜永久性肽（ACT-1）归一化，旨在抑制ZO-1与CX43体外的相互作用。 将使用几种方法，包括免疫共定位分析，蛋白质印迹，FRET（荧光共振能量转移），免疫沉淀，蛋白质 - 蛋白质交联和电子显微镜。另外，将使用心电图，超声心动图和荧光电压敏感染料的光学映射评估心脏功能。此外，在AIM 2中，活细胞成像的成像 还将在高葡萄糖条件下进行CX43和ZO-1的荧光标记构建体。 美国糖尿病患者的糖尿病患者中有80％死于心血管并发症，导致50000多人每年死亡。该项目将更好地了解糖尿病心脏病的基本机制，并可能导致血压和糖控制超出血压和糖的新疗法。