Alpha1-Adrenoceptor Subtype Signaling in Preconditioning

预处理中的 Alpha1-肾上腺素受体亚型信号转导

• 批准号: 6757902
• 负责人: GREGG ROKOSH
• 金额: $ 32.07万
• 依托单位: UNIVERSITY OF LOUISVILLE
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-09-01 至 2007-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6757902
• 关键词: alpha adrenergic receptor; apoptosis; biological signal transduction; cytoprotection; epidermal growth factor; gene therapy; genetic transcription; genetically modified animals; heat shock proteins; immunoprecipitation; laboratory mouse; mitogen activated protein kinase; myocardial ischemia /hypoxia; phosphatidylinositol 3 kinase; protein isoforms; protein kinase C; protein tyrosine kinase; reperfusion; serine threonine protein kinase; thioredoxin; transfection /expression vector

DESCRIPTION (provided by applicant): Myocardial preconditioning (PC) protects the heart from the consequences of ischemic heart disease and ischemia - reperfusion injury. Catecholamines released during ischemia induce myocardial PC by activating alpha1-adrenoceptors(AR) in the heart. Two alpha1-AR subtypes are expressed in the heart. Recently, in alpha1-AR subtype knockout (KO) mice, each alpha1-AR subtype was found to activate different:signaling pathways. The broad objective of this project is to define the subtype(s) that are responsible for catecholamine induced PC, the mechanisms by which PC is induced, and ultimately whether therapeutics can be utilized to capitalize on subtype specific signaling to benefit cardiac health. The alpha1-AR subtype(s) responsible for catecholamine induced early and late PC will be determined using alpha1-AR subtype KO mice in loss of function studies. An in vivo mouse model of ischemic PC will be used to study the effect of alpha1-AR- and ischemia- induced PC on infarct size. An in vitro mouse Langendorf heart model will be used to study the effect of alpha1-AR- and ischemia- induced PC on myocardial stunning. Subtype specific signaling cascade studies will focus on antiapoptotic signaling via PI3K/AKT, reactive oxygen species, protein kinase C, mitogen activated protein kinases, and tyrosine kinase activation during preconditioning protocols. Signaling complexes formed at each subtype that can account for differences in subtype signaling will be studied using tagged alpha1A and alpha1B subtypes in immunoprecipitation experiments. Late PC requires gene transcription. We have identified several candidate genes that may participate in late PC. The regulation of gene expression and how these gene products contribute to PC will be studied. The ability to precondition the heart for prolonged periods would be an important contribution to many clinical applications where:the heart is exposed to or at risk during prolonged ischemic heart disease or with ischemia - reperfusion injury. The benefits of overexpressing and enhancing alpha1-AR subtype-specific signaling responsible for PC will be tested using a gene therapy approach. The subtype will be expressed in the heart acutely using an adenovirus vector.

描述（由申请人提供）：心肌预处理（PC）可保护心脏免受缺血性心脏病和缺血的后果 - 再灌注损伤。 缺血期间释放的儿茶酚胺通过在心脏中激活α1-肾上腺素受体（AR）诱导心肌PC。 在心脏中表达了两个alpha1-ar亚型。 最近，在Alpha1-AR亚型敲除（KO）小鼠中，发现每种alpha1-ar亚型都激活不同：信号通路。 该项目的广泛目标是定义负责儿茶酚胺诱导的PC的亚型，诱导PC的机制以及最终是否可以利用治疗剂来利用亚型特定信号传导以使心脏健康受益。 负责儿茶酚胺诱导的早期和晚期PC的α1-AR亚型将使用alpha1-ar亚型KO小鼠在功能研究损失中确定。 缺血性PC的体内小鼠模型将用于研究α1-AR-和缺血诱导的PC对梗死大小的影响。 体外小鼠Langendorf心脏模型将用于研究α1-AR-和缺血诱导的PC对心肌惊人的影响。 亚型特异性信号传导级联研究将通过PI3K/AKT，反应性氧，蛋白激酶C，有丝分裂原活化蛋白激酶和酪氨酸激酶激活在预处理方案过程中，将重点放在抗凋亡信号传导上。 在免疫沉淀实验中，将使用标记的alpha1a和alpha1b亚型研究在每个亚型上形成的可以解释亚型信号差异的信号复合物。 晚期PC需要基因转录。 我们已经确定了可能参与PC后期的几个候选基因。 将研究基因表达的调节以及这些基因产物如何对PC进行研究。 长时间前进的心脏的能力将是对许多临床应用的重要贡献：在长期缺血性心脏病或缺血 - 再灌注损伤的过程中，心脏会暴露于或面临风险。 过表达和增强负责PC的Alpha1-AR亚型特异性信号的好处将通过基因治疗方法测试。 亚型将在心脏中使用腺病毒载体敏锐地表达。