Ectonucleotidases in ischemic heart disease

美国每年有超过100万人患有心肌梗死（MI）。心肌 心肌梗死（MI）引起强烈的炎症反应。旁分泌和自分泌释放细胞外ATP 通过嘌呤能P2受体（P2 X和P2 Y）进行信号传导的eATP是巨噬细胞的有效调节剂， 成纤维细胞功能细胞外ATP被跨膜蛋白Ectonucleoside triphosphate水解 二磷酸水解酶1（CD 39）产生腺苷一磷酸（AMP），从而阻止促炎性 ATP介导的信号传导。该项目的目标是确定巨噬细胞和成纤维细胞的作用- 在MI后心脏修复中表达CD 39。为实现这一目标，我们提出以下建议：目标1： 确定CD 39上调是否是限制自分泌ATP驱动的 炎症，防止过度的巨噬细胞反应，并保护心肌梗死后纤维化， 将：1）确定CD 39活性如何影响TLR-4依赖性和IL-4依赖性巨噬细胞功能， 2）确定CD 39活性对体内巨噬细胞表型从 3）确定巨噬细胞CD 39在心肌梗死后修复过程中的作用， 心肌梗死后修复纤维化。目的2：分析CD 39介导的抑制CD 39表达的嘌呤能通路， TGF-β1对心脏成纤维细胞的激活作用及CD 39上调对成纤维细胞的调节作用 功能和调节心肌梗死后的心脏修复，我们将1）确定下游靶点， CD 39减弱TGF-β1介导的心脏成纤维细胞炎症和纤维化反应，2）确定 在心脏修复过程中CD 39对体内心脏成纤维细胞表型的影响，以及3）确定 成纤维细胞CD 39对MI后修复期间体内细胞外基质重塑的影响。次要目的：确定 CD 39表达对细胞外基质重塑的影响，我们将使用最先进的MALDI成像 质谱以确定MI后心脏ECM重塑的早期和晚期生物特征， 确定CD 39对ECM重塑的影响。这些研究的结果将揭示基本的 CD 39调节MI后心肌修复的途径，并可能允许新的治疗方法 不仅用于治疗心脏的纤维变性疾病，而且用于治疗皮肤、肺、骨髓、肝或肾的纤维变性疾病， 从而提供重要的平移影响。

More than 1 million people in the United States suffer a myocardial infarction (MI) each year. Myocardial infarction (MI) evokes an intense inflammatory response. Paracrine and autocrine released extracellular ATP (eATP), signaling through purinergic P2 receptors (P2X and P2Y), is a potent modulator of macrophage and fibroblast function. Extracellular ATP is hydrolyzed by the transmembrane protein Ectonucleoside triphosphate diphosphohydrolase 1 (CD39) to yield adenosine monophosphate (AMP), thereby halting pro-inflammatory ATP-mediated signaling. This goal of the project is to define the role of the macrophage and fibroblast- expressed CD39 on post-MI cardiac repair. To accomplish this goal we propose the following: Aim 1: To determine whether CD39 up-regulation is a protective mechanism that constrains autocrine ATP-driven inflammation, preventing exaggerated macrophage responses, and protecting from adverse post-MI fibrosis we will: 1) determine how CD39 activity impacts TLR-4-dependent and IL-4-dependent macrophage functions in vitro, 2) determine the impact of CD39 activity on the in vivo macrophage phenotypic transition from inflammatory to profibrotic functions during post-MI repair, and 3) Determine the role of macrophage CD39 on post-MI repair fibrosis in vivo. Aim 2: To dissect the purinergic pathways involved in CD39-mediated restraint of TGF-β1 activation of cardiac fibroblasts and determine the role of CD39 upregulation in modulating fibroblast function and regulating cardiac repair following MI we will 1) determine the downstream targets through which CD39 attenuates TGF-β1-mediated cardiac fibroblast inflammatory and fibrotic responses, 2) determine the impact of CD39 on the in vivo cardiac fibroblast phenotype during cardiac repair and 3) determine the impact of fibroblast CD39 on in vivo extracellular matrix remodeling during post-MI repair. Secondary Aim: To determine the impact of CD39 expression extracellular matrix remodeling we will use state-of-the-art MALDI-imaging mass spectroscopy to define the early and late biosignatures of cardiac ECM remodeling post-MI and determine the impact of CD39 on ECM remodeling. The outcomes of these studies will reveal the fundamental pathways by which CD39 regulates post-MI myocardial repair and could allow novel therapeutic approaches not only to treat fibrotic disorders of the heart, but also of the skin, lungs, bone marrow, liver, or kidneys, thereby providing an important translational impact.