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: 8608431
• 负责人: JOHN A AUCHAMPACH
• 金额: $ 43.84万
• 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/8608431
• 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）是美国第一大死因，缺血性心脏病是 CVD 患者死亡率的首位。大多数缺血性心脏病患者的冠状动脉阻塞，心脏组织缺乏灌注（缺血），导致心肌损伤和再灌注后进一步损伤。花生四烯酸 (AA)、11,12- 和 14,15-环氧二十碳三烯酸 (EET) 的新型 CYP 环氧合酶代谢物在缺血期间，特别是在再灌注后增加。内源产生的 EET 和外源施用的 EET 对狗、大鼠和小鼠心脏产生显着的心脏保护作用；然而，造成这些有益作用的机制仍不清楚。根据有趣的初步数据，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两个主要参与者。这项研究将利用大鼠和一氧化氮合酶 (NOS) 亚型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来深入阐明 EET 诱导的心脏保护作用的关键因素。待检验的假设是，在缺血/再灌注时，心肌细胞和心脏成纤维细胞释放的 EET 是有效的心脏保护剂，可诱导内源性 NO 的进一步释放以产生其有益作用。具体来说，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 诱导的心脏保护作用的介质。大鼠和 NOS 敲除小鼠和心肌细胞（H9c2 细胞）将用于证明 EET 诱导的心脏保护作用是通过 NO 信号通路介导的。 NOS 亚型（eNOS、nNOS 或 iNOS）及其由 EET 激活的信号通路将被识别。 (2)确定心脏成纤维细胞在释放EETs和可能的NO作为调节因子中发挥作用，以保护心肌细胞免受缺氧/复氧损伤。 (3)确定EETs和阿片类药物这两种主要心脏保护因子在心脏保护中是否存在串扰。重要的是，EET 很容易被可溶性环氧化物水解酶 (sEH) 水解为二羟基二十碳三烯酸 (DHET)，这对心肌梗塞的大小没有影响。这一发现表明，具有优异药代动力学的新型合成 EET 类似物可能代表比 sEH 抑制剂和不稳定 EET 更好的治疗靶点。新合成的长效 EET 类似物将用于阐明 EET 的信号传导途径并减少梗塞面积。作为该领域的领导者，鉴定内源性 EET 的新型稳定类似物将是该项目的主要目标，并在心脏损伤的细胞和整体动物模型中展示其强大的抗缺血和抗炎作用。长期目标是更好地表征具有多个治疗靶点的新型内源性系统，这可能建议联合治疗以更好地治疗缺血/再灌注损伤。