ARNT: A novel regulator of cardiac vascular endothelial barrier function in heart failure

ARNT：心力衰竭中心血管内皮屏障功能的新型调节剂

• 批准号: 10317071
• 负责人: Rongxue Wu
• 金额: $ 41.15万
• 依托单位: UNIVERSITY OF CHICAGO
• 依托单位国家: 美国
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-12-15 至 2023-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10317071
• 关键词: ARNT gene; Address; Adherens Junction; Attenuated; Binding; Biological Assay; Blood Vessels; Blood flow; CRISPR/Cas technology; Cardiac; Cardiac Edema; Cardiac Myocytes; Cell Death; Cells; Clinical; Coculture Techniques; Congestive Heart Failure; Consensus; Data; Development; Edema; Endothelial Cells; Endothelium; Evans blue stain; Extracellular Matrix; Fractionation; Functional disorder; Gene Expression; Gene Silencing; Genetic Transcription; Goals; Heart; Heart Diseases; Heart failure; Hemorrhage; Heterodimerization; Histologic; Homodimerization; Human; Hypoxia; Hypoxia Inducible Factor; Impairment; In Vitro; Inhibition of Matrix Metalloproteinases Pathway; Ischemia; Knock-out; Knockout Mice; Knowledge; Lead; Link; Luciferases; Magnetic Resonance; Matrix Metalloproteinase Inhibitor; Matrix Metalloproteinases; Measures; Mediating; Microarray Analysis; Microvascular Permeability; Molecular; Mus; Muscle Cells; Mutation; Myocardial Infarction; Myocardial Ischemia; Myocardial tissue; Myocardium; Nuclear Matrix; Pathway interactions; Patient-Focused Outcomes; Permeability; Pharmacology; Plasmids; Play; Proteins; Recovery; Reperfusion Injury; Reperfusion Therapy; Reporter; Role; Site; Small Interfering RNA; Stromelysin 1; System; Testing; Tight Junctions; Transcription Factor AP-1; Vascular Endothelium; Vascular Permeabilities; Visualization; cadherin 5; chromatin immunoprecipitation; cofactor; electric impedance; experimental study; heart function; hemodynamics; hypoxia inducible factor 1; improved; in vivo; inhibitor; interstitial; ischemic injury; mature animal; myocardial damage; new therapeutic target; novel; novel strategies; occludin; overexpression; prevent; promoter; transcription factor

Abstract After a heart attack, restoring blood flow to the heart (i.e., reperfusion) is critically necessary to limit the amount of myocardial tissue that is damaged by ischemic injury; however, reperfusion itself leads to its own type of myocardial damage (ischemia-reperfusion [IR] injury) for which there is no treatment and that can lead to chronic heart failure (HF). Thus, knowledge of the molecular mechanisms that are induced by cardiac reperfusion is urgently needed to identify novel strategies for preventing IR injury. Cardiac edema, which is mainly caused by an increase in cardiac vascular permeability, is one of the primary contributors to IR injury, and the results from my preliminary studies indicate that vascular permeability is limited by the expression of Aryl Hydrocarbon Receptor Nuclear Translocator (ARNT), also known as hypoxia-inducible factor 1β, in endothelial cells (ECs). I have recently generated a line of mice carrying an inducible, EC-specific ARNT knockout mutation (ecARNT–/–), and the results from experiments with these mice indicate that the loss of ecARNT expression during reperfusion leads to cardiac hemorrhage, and that when the ecARNT–/– mutation is induced in adult animals, cardiac edema develops and gradually progresses to HF. Thus, ecARNT appears to be a crucial regulator of endothelial barrier function, but the role of ecARNT in heart disease is not currently being investigated. The experiments described in this proposal address this unmet need by studying the mechanisms of ARNT-regulated endothelial barrier function after IR injury and their impact on the progression of HF. Furthermore, our preliminary studies suggest that ARNT also regulates the expression of matrix metalloproteinase 3 (MMP3), which cleaves proteins that form junctions between adjacent ECs; thus, we will conduct in-vitro experiments with cultured ECs to determine whether MMP3 inhibition can reverse the impaired endothelial barrier function associated with ecARNT deletion and if so, elucidate the mechanisms that support this observation. We will also use the MMP3 inhibitors in ecARNT–/– mice and generate a line of ecARNT/MMP3 double-knockout mice to determine whether MMP3 inhibition can restore vascular integrity and limit the progression of IR-induced HF. Upon completion, we expect the results from our studies to have identified new therapeutic targets and strategies for improving patient outcomes by reducing cardiac edema during the early stages of recovery from a heart attack and preventing (or delaying) the progression of heart disease.

抽象的 心脏病发作后，恢复心脏血流（即再灌注）对于限制血流量至关重要 因缺血性损伤而受损的心肌组织；然而，再灌注本身会导致其自身类型的 心肌损伤（缺血再灌注 [IR] 损伤），无法治疗，可能导致 慢性心力衰竭（HF）。因此，了解心脏引起的分子机制 迫切需要再灌注来确定预防 IR 损伤的新策略。心脏水肿，这是 主要由心脏血管通透性增加引起，是IR损伤的主要原因之一， 我的初步研究结果表明血管通透性受到表达的限制 芳基烃受体核转运蛋白（ARNT），也称为缺氧诱导因子 1β，在 内皮细胞（EC）。我最近培育了一系列携带可诱导的 EC 特异性 ARNT 的小鼠 敲除突变（ecARNT–/–），这些小鼠的实验结果表明， 再灌注期间 ecARNT 表达会导致心脏出血，当 ecARNT–/– 突变发生时 在成年动物中诱导，出现心脏水肿并逐渐进展为心力衰竭。因此，eCARNT 似乎 是内皮屏障功能的关键调节因子，但目前还不清楚 ecARNT 在心脏病中的作用 正在接受调查。本提案中描述的实验通过研究解决了这一未满足的需求 IR损伤后ARNT调节内皮屏障功能的机制及其对进展的影响 高频。此外，我们的初步研究表明 ARNT 还调节基质的表达 金属蛋白酶 3 (MMP3)，可切割形成相邻 EC 之间连接的蛋白质；因此，我们将 用培养的 EC 进行体外实验，以确定 MMP3 抑制是否可以逆转受损的细胞 内皮屏障功能与 ecARNT 缺失相关，如果是这样，请阐明支持的机制 这一观察。我们还将在 ecARNT–/– 小鼠中使用 MMP3 抑制剂，并产生一系列 ecARNT/MMP3 双敲除小鼠以确定 MMP3 抑制是否可以恢复血管完整性和 限制 IR 诱发的心力衰竭的进展。完成后，我们期望我们的研究结果 确定了新的治疗目标和策略，通过减少心脏水肿来改善患者的预后 在心脏病发作恢复的早期阶段并预防（或延缓）心脏病的进展 疾病。