EET-Induced Cardioprotection: Role of Opioids and Nitric Oxide (NO)

EET 诱导的心脏保护作用：阿片类药物和一氧化氮 (NO) 的作用

• 批准号: 8431782
• 负责人: JOHN A AUCHAMPACH
• 金额: $ 42.66万
• 依托单位: MEDICAL COLLEGE OF WISCONSIN
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-02-21 至 2016-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8431782
• 关键词: Acids; Address; Agonist; Animal Model; Anti-Inflammatory Agents; Anti-inflammatory; Arachidonic Acids; Canis familiaris; Cardiac; Cardiac Myocytes; Cardiotonic Agents; Cardiovascular Diseases; Cause of Death; Cell model; Cells; Coculture Techniques; Combined Modality Therapy; Conditioned Culture Media; Coronary artery; Data; Drug Kinetics; Endogenous Factors; Epoxide hydrolase; Exhibits; Fibroblasts; Genetic; Goals; Heart; Hydrolysis; Hypoxia; Individual; Infarction; Injury; Ischemia; Knockout Mice; Knowledge; Laboratories; Lead; Life; Mediating; Mediator of activation protein; Mission; Mus; Myocardial; Myocardial Ischemia; Myocardium; Nitric Oxide; Nitric Oxide Signaling Pathway; Nitric Oxide Synthase; Opioid; Opioid Receptor; Oxidative Stress; Pathway interactions; Patients; Perfusion; Play; Production; Protein Isoforms; Rattus; Reperfusion Injury; Reperfusion Therapy; Research; Role; Signal Pathway; Small Interfering RNA; System; Testing; Tissues; United States; United States National Institutes of Health; analog; base; improved; inhibitor/antagonist; insight; knock-down; man; mortality; myocardial infarct sizing; novel; therapeutic target

DESCRIPTION (provided by applicant): Cardiovascular disease (CVD) is the number one cause of death in the United States and ischemic heart disease is the leader in mortality among patients with CVD. Most individuals with ischemic heart disease have blocked coronary arteries and cardiac tissue has a lack of perfusion (ischemia), resulting in myocardial damage and further injury following reperfusion. The novel CYP-epoxygenase metabolites of arachidonic acid (AA), 11,12- and 14,15-epoxyeicosatrienoic acids (EETs) are increased during ischemia and particularly following reperfusion. Endogenously produced EETs and exogenously administered EETs produce marked cardioprotective effects in dog, rat and mouse hearts; however, the mechanisms responsible for these beneficial effects remain unclear. Based on intriguing preliminary data, opioid receptors and nitric oxide (NO) release may be 2 major players in EET-mediated cardioprotection. This study will utilize rats and genetic knockout mice of nitric oxide synthase (NOS) isoforms as well as cellular models of cardiomyocytes and cardiac fibroblasts to elucidate in depth, the key contributing factors responsible for EET-induced cardioprotection. The hypothesis to be tested is that upon ischemia/reperfusion, EETs released from cardiomyocytes and cardiac fibroblasts are potent cardioprotective agents that induce the further release of endogenous NO to produce their beneficial effects. Specifically, we will (1) determine that nitric oxide (NO) is a mediator of EET-induced cardioprotection in intact rat and mouse hearts and cardiomyocytes. Both rats and NOS knockout mice and cardiomyocytes (H9c2 cells) will be used to demonstrate that EET-induced cardioprotection is mediated via a NO signaling pathway. NOS isoforms (eNOS, nNOS or iNOS) and their signaling pathways activated by the EETs will be identified. (2) Determine that cardiac fibroblasts play a role in releasing EETs and possibly NO as regulatory factor(s) to protect cardiomyocytes from hypoxia/reoxygenation injury. (3) Determine if cross-talk occurs between the two major cardioprotective factors, EETs and opioids, in cardioprotection. Importantly, EETs are readily hydrolyzed by soluble epoxide hydrolase (sEH) to dihydroxyeicosatrienoic acids (DHETs) which have no effect on myocardial infarct size. This finding suggests that novel synthetic EET analogs with superior pharmacokinetics may represent better therapeutic targets than sEH inhibitors and labile EETs. The newly synthesized longer-acting EET analogs will be used to elucidate signaling pathways of the EETs and to reduce infarct size. As leaders in the this field, identification of novel stable analogs of endogenous EETs will be a major goal of this project as well as demonstrating their powerful anti-ischemic and anti-inflammatory actions in cellular and whole animal models of cardiac injury. The long term goal is to obtain better characterization of a novel endogenous system with multiple therapeutic targets that may suggest combined therapy for better treatment of ischemia/reperfusion injury.

描述（由申请人提供）：心血管疾病（CVD）是美国死亡的第一名，缺血性心脏病是CVD患者死亡率的领导者。大多数缺血性心脏病的患者冠状动脉动脉阻塞，心脏组织缺乏灌注（缺血），导致心肌损伤和再灌注后进一步的损伤。新型的CYP-氧合酶代谢产物（AA），11,12-和14,15-环氧化酸酯（EET）在缺血期间增加，尤其是在再生后增加。内源性产生的EET和外源性的Eets在狗，大鼠和小鼠心中产生明显的心脏保护作用。但是，负责这些有益效应的机制尚不清楚。基于有趣的初步数据，阿片受体和一氧化氮（NO）释放可能是EET介导的心脏保护作用的2个主要参与者。这项研究将利用一氧化氮合酶（NOS）同工型的大鼠和遗传基因敲除小鼠以及心肌细胞和心脏成纤维细胞的细胞模型深度阐明，这是导致EET诱导的心脏保护的关键因素。要检验的假设是，在缺血/再灌注后，从心肌细胞释放的EET和心脏成纤维细胞是有效的心脏保护剂，可诱导内源性NO进一步释放以产生其有益作用。具体而言，我们将（1）确定一氧化氮（NO）是完整大鼠和小鼠心脏和心肌细胞中EET诱导的心脏保护的介体。大鼠和NOS敲除小鼠和心肌细胞（H9C2细胞）均可证明通过NO信号传导途径介导EET诱导的心脏保护。 NOS同工型（ENOS，NNOS或INOS）及其由EET激活的信号通路。 （2）确定心脏成纤维细胞在释放EET方面发挥作用，并且可能没有作为保护心肌细胞免受缺氧/雷氧损伤的调节因素的作用。 （3）确定在心脏保护中，在两个主要的心脏保护因素（EET和阿片类药物）之间是否发生串扰。重要的是，EET很容易被可溶性环氧化物水解酶（SEH）水解为二羟基甲酸酯（DHET），这对心肌梗塞大小没有影响。这一发现表明，具有优质药代动力学的新型合成EET类似物可能比SEH抑制剂和不稳定的EET代表更好的治疗靶标。新合成的较长的EET类似物将用于阐明EET的信号通路并降低梗塞大小。作为该领域的领导者，对内源性EET的新型稳定类似物的识别将是该项目的主要目标，并在心脏损伤的细胞和整个动物模型中展示了它们强大的抗异流和抗炎作用。长期目标是获得具有多种治疗靶点的新型内源系统的更好表征，这可能建议将治疗方法合并，以更好地治疗缺血/再灌注损伤。