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CYTOPROTECTIVE EFFECTS OF INFLAMMATION MEDIATED MEMBRANE REPAIR

炎症介导的膜修复的细胞保护作用

基本信息

批准号：
8984902
负责人：
Douglas L Mann
金额：
$ 38.75万
依托单位：
WASHINGTON UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2012
资助国家：
美国
起止时间：
2012-01-01 至 2017-12-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8984902
关键词：
Acute Anterior Apoptotic Arteries Blood flow Cardiac Cardiac Myocytes Cell Death Cell Membrane Permeability Cell membrane Cells Chest Cytokine Signaling Cytoprotection DYSF gene Defect Dermal Development Dominant-Negative Mutation Emergency response Exocytosis Fibroblasts Figs - dietary Gene Expression Profiling Genes Goals Heart Heart Injuries Human Hypoxia In Vitro Infarction Inflammation Injury Ischemia Laboratories Laboratory Study Lead Left Ligation Maintenance Mechanics Mediating Membrane Modeling Mus Myocardial Myocardial Infarction Myocardial Ischemia Myocardial Reperfusion Necrosis Neonatal Pathway interactions Patients Pluripotent Stem Cells Rattus Receptors, Tumor Necrosis Factor, Type II Reperfusion Injury Reperfusion Therapy Research Resolution Role Series Signal Pathway Signal Transduction Signaling Molecule Signaling Protein TNF Receptor-Associated Factors TNF gene TNFRSF1A gene TRAF2 gene Testing Time Tissues Transgenic Mice Tumor Necrosis Factor Receptor comparative cytokine design dysferlinopathies in vivo myocardial damage novel novel therapeutics overexpression receptor repaired research study response restoration

项目摘要

The long-term goal of this research initiative is to delineate the cytoprotective role of proinflammatory cytokines in myocardial ischemia reperfusion (I/R) injury. We have previously shown that the cytoprotective effects of tumor necrosis factor (TNF) are conveyed by both the type 1 (TNFR1) and type 2 (TNFR2) TNF receptors. Noting that TRAF2 (tumor necrosis factor receptor associated factor 2) was the only signaling protein that was common to both receptors, we have performed experiments in isolated cardiac myocytes, as well as transgenic mice with cardiac restricted overexpression of TRAF2 (MHC-TRAF2 mice) and a dominant negative TRAF2 (MHC-TRAF2-DN mice) that have identified an indispensable role for TRAF2 in TNF mediated cytoprotective signaling. To further identify the mechanisms for the cytoprotective effects of TRAF2 we performed comparative gene expression profiling in the hearts of MHC-TRAF2 and MHC-TRAF2-DN mice and identified a unique "emergency response gene" termed dysferlin, that is responsible for maintaining Ca++ dependent cardiac myocyte plasma membrane integrity. Accordingly, we propose to focus the present application on delineating the role of TRAF2 mediated membrane repair as a novel cytoprotective mechanism in I/R injury, by determining whether dysferlin is necessary and/or sufficient for mediating these effects. Specific Aim 1 will test the hypothesis that the cytoprotective effects of TRAF2 in I/R injury ex vivo are mediated, at least in part, through dysferlin-mediated maintenance of cardiac myocyte plasma membrane integrity. Specific Aim 2 will test whether (1) the cytoprotective effects of TRAF2 in I/R injury in vivo are mediated, at least in part, through dysferlin-mediated maintenance of cardiac myocyte plasma membrane integrity (2) and whether the beneficial effects of TRAF2 and dysferlin with respect to delimiting tissue injury in vivo are accompanied by faster time of resolution of myocardial inflammation. Specific Aim 3 will test whether (1) the cytoprotective effects of TRAF2 are mediated, at least in part, through enhanced exocytotic membrane repair and enhanced membrane integrity in isolated rat neonatal cardiac myocytes; and (2) inducible pluripotent stem cells (iPSCs) derived human cardiac myocytes generated from dermal fibroblasts from patients with dysferlinopathy have impaired exocytosis and increased cell death following hypoxia reoxygenation injury in vitro. We expect that the results of Specific Aims 1 - 3 will provide definitive information with respect to the mechanisms for TRAF2-mediated cytoprotection in the heart, as well as allow us to determine whether dysferlin, a novel Ca++ dependent emergency response gene, is necessary and/or sufficient to mediate the cytoprotective effects of TRAF2 following I/R injury.

该研究计划的长期目标是阐明促炎细胞因子的细胞保护作用心肌缺血再灌注（I/R）损伤。我们之前已经证明了细胞保护作用肿瘤坏死因子 (TNF) 由 1 型 (TNFR1) 和 2 型 (TNFR2) TNF 受体传递。注意到 TRAF2（肿瘤坏死因子受体相关因子 2）是唯一的信号蛋白这两种受体共有，我们在分离的心肌细胞以及转基因细胞中进行了实验心脏限制性 TRAF2 过度表达的小鼠（MHC-TRAF2 小鼠）和显性失活 TRAF2 （MHC-TRAF2-DN 小鼠）已确定 TRAF2 在 TNF 介导中发挥着不可或缺的作用细胞保护信号传导。为了进一步确定 TRAF2 细胞保护作用的机制，我们对 MHC-TRAF2 和 MHC-TRAF2-DN 小鼠心脏进行比较基因表达谱分析鉴定出一种独特的“紧急反应基因”，称为 Dysferlin，负责维持 Ca++ 依赖心肌细胞质膜的完整性。因此，我们建议重点关注当前应用描述 TRAF2 介导的膜修复作为一种新型细胞保护机制的作用在 I/R 损伤中，通过确定 Dysferlin 是否对于介导这些作用是必要和/或充分的。具体目标 1 将检验以下假设：TRAF2 在离体 I/R 损伤中的细胞保护作用是至少部分地通过 Dysferlin 介导的心肌细胞质膜维持介导正直。具体目标 2 将测试 (1) TRAF2 在体内 I/R 损伤中的细胞保护作用是否至少部分地通过 Dysferlin 介导的心肌细胞质膜维持介导完整性 (2) 以及 TRAF2 和 Dysferlin 在界定组织损伤方面是否具有有益作用体内伴随着心肌炎症的更快消退时间。具体目标 3 将测试是否 (1) TRAF2 的细胞保护作用至少部分是通过增强的胞吐膜介导的修复并增强离体大鼠新生心肌细胞的膜完整性； (2)诱导型多能干细胞 (iPSC) 源自人心肌细胞，由真皮成纤维细胞产生铁蛋白病患者的胞吐作用受损，缺氧后细胞死亡增加体外复氧损伤。我们预计具体目标 1 - 3 的结果将提供明确的结果有关 TRAF2 介导的心脏细胞保护机制的信息，以及允许我们来确定 Dysferlin（一种新型 Ca++ 依赖性紧急反应基因）是否必要和/或足以介导 I/R 损伤后 TRAF2 的细胞保护作用。