Effect of Adenosine A2 receptor activation on the mitochondrial death pathway

腺苷A2受体激活对线粒体死亡途径的影响

基本信息

批准号：
7842054
负责人：
ZHELONG XU
金额：
$ 22.38万
依托单位：
UNIV OF NORTH CAROLINA CHAPEL HILL
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/7842054
关键词：
1-Phosphatidylinositol 3-Kinase Accounting Acute myocardial infarction Adenosine Adenosine A2 Receptors Adenosine-5&apos -(N-ethylcarboxamide)Agonist Agreement Apoptosis Apoptotic Attenuated Biological Cardiac Myocytes Cellular biology Cessation of life Chelating Agents Cyclic AMP-Dependent Protein Kinases Cyclic GMP Data Gene Targeting Generations Genes Genetic Glycogen Synthase Kinase 3 Glycogen Synthase Kinases Goals Heart Heart Block Heat-Shock Proteins 90 Infarction Ischemia Ischemic Preconditioning Knock-out Knockout Mice Lead Measures Mediating Membrane Potentials Mitochondria Molecular Biology Myocardial Ischemia Myocardium Necrosis Nitric Oxide Oxidants Pathway interactions Patients Pharmacology Phosphorylation Physiology Pilot Projects Play Prevention Preventive Protein Tyrosine Kinase Rattus Receptor Activation Reperfusion Injury Reperfusion Therapy Reporting Role Signal Pathway Signal Transduction Techniques Testing Work Zinc clinically significant design indexing inhibitor/antagonist insight knockout gene mitochondrial dysfunction mitochondrial membrane mitochondrial permeability transition pore myocardial infarct sizing novel overexpression prevent protective effect receptor

项目摘要

DESCRIPTION (provided by applicant): A large number of recent studies have associated a mitochondrial death pathway at reperfusion with both necrosis and apoptosis. Preventing the mitochondrial death pathway, therefore, is a prerequisite for successful cardioprotection at reperfusion. Although adenosine A2 receptor activation at reperfusion has been proposed to protect the heart, its mechanisms are still not clear. The objective of this proposal is to determine the effects of A2 receptor activation on the mitochondrial death pathway and to elucidate the signaling mechanisms underling the effects of A2 receptor activation. We hypothesize that stimulation of A2 receptor activation by NECA at reperfusion interdicts the mitochondrial death pathway through a signal cascade involving eNOS, NO, PKG, zinc, and GSK-3. We will test these hypotheses by using diverse techniques of cell biology, molecular biology, physiology, pharmacology, and gene targeting. Aim 1 will determine the effects of A2 receptor activation at reperfusion on the mitochondrial death pathway by measuring mitochondrial function, infarct size, and indexes of apoptosis. Aim 2 will determine the mechanisms by which A2 receptor activation produces NO by defining the roles of PKA, tyrosine kinase, and HSP90 in activation of eNOS. Aim 3 will determine the role of PKG in the protective action of A2 receptor activation. We will define the role of PKG by overexpressing or knocking out the PKG gene. Aim 4 will ascertain the downstream targets of PKG activation that lead to the preventive effects of A2 receptor activation on the mitochondrial death pathway. Towards this goal we will characterize the roles of intracellular free zinc, mitochondrial KATP channels, and GSK-3. The successful execution of this proposal should produce important new insights into the signaling mechanisms underlying the protective effects of A2 receptor activation at reperfusion against ischemia/reperfusion injury, and have great clinical significance for treating patients with acute myocardial infarction.

描述（由申请人提供）：大量最近的研究将再灌注时的线粒体死亡途径与坏死和凋亡均相关。因此，防止线粒体死亡途径是在再灌注时成功进行心脏保护的先决条件。尽管已经提出了在再灌注时腺苷A2受体激活以保护心脏，但其机制仍然尚不清楚。该建议的目的是确定A2受体激活对线粒体死亡途径的影响，并阐明A2受体激活作用的信号机制。我们假设NECA在再灌注中刺激A2受体激活的刺激通过涉及eNOS，NO，PKG，锌和GSK-3的信号级联反应的线粒体死亡途径。我们将通过使用细胞生物学，分子生物学，生理学，药理学和基因靶向的各种技术来检验这些假设。 AIM 1将通过测量线粒体功能，梗塞大小和凋亡指数来确定A2受体激活对再灌注对线粒体死亡途径的影响。 AIM 2将通过定义PKA，酪氨酸激酶和HSP90在ENOS激活中的作用来确定A2受体激活产生NO的机制。 AIM 3将确定PKG在A2受体激活的保护作用中的作用。我们将通过过表达或淘汰PKG基因来定义PKG的作用。 AIM 4将确定PKG激活的下游靶标，从而导致A2受体激活对线粒体死亡途径的预防作用。为了实现这一目标，我们将表征细胞内游离锌，线粒体KATP通道和GSK-3的作用。该提案的成功执行应产生重要的新见解，以对反对缺血/再灌注损伤时A2受体激活的保护作用的信号传导机制产生重要的作用，并且对于治疗急性心肌梗死患者的临床意义很高。