ConProject-001

项目摘要 主动脉瘤(Aa)是一个重要的临床问题，主动脉破裂的高风险导致 猝死。目前，还没有治疗动脉瘤的药物疗法，也没有明确的 了解AA形成的病理生物学是开发治疗药理学方法的关键。 最近的研究表明，细胞可以通过pAnnexin 1(Panx1)以受控的方式释放ATP。 通过嘌呤能的P2X或P2Y受体传递信号的通道。三磷酸腺苷是一种大量释放的核苷酸。 在组织损伤后，如再生障碍性贫血，可作为一种“危险信号”来调节炎症。我们的数据表明 血管内皮细胞(ECs)上的Panx1是血管炎症的重要介质 腹型AA(AAA)，是细胞外ATP的主要来源。Panx1的表达水平最高 动脉网络，尤其是在主动脉内皮细胞。这项建议的科学前提集中在 主动脉内皮细胞、平滑肌细胞和相关免疫细胞之间的串扰来描绘Panx1- 介导AAA进展中的信号转导。因此，该提案将检验EC Panx1的总体假设 信号是信号级联的主要早期炎症介质，通过释放ATP导致 血管平滑肌细胞活化、白细胞浸润和血管炎症。使用新的可诱导细胞- 特定的基因敲除动物，特定的药理Panx1抑制剂和P2X/P2Y拮抗剂，我们将 阐明了这一以前未知的AAA病理生物学机制。目标1将确定EC Panx1是否 信号通过三磷酸腺苷的释放及其与主动脉平滑肌细胞的串扰以及 确定P2X7受体是否是AAA的主要决定因素。我们还将调查Panx1是否 抑制可以治疗小鼠模型中预先形成的AAA。Aim 2将确定Panx1信号是否在 急性再生障碍性贫血时白细胞的活化和浸润。Panx1和特异性嘌呤能受体在血管紧张素转换酶中的作用 巨噬细胞以及Panx1是否介导中性粒细胞跨内皮细胞迁移将被破译。 AIM 3将确定药物抑制Panx1或特定的P2受体是否可以治疗慢性AAA 炎症性、大动物猪AAA模型。我们的研究将为我们提供新的洞察机制 主动脉内皮细胞、平滑肌细胞和免疫细胞之间的分子信号相互作用 (巨噬细胞和中性粒细胞)，将Panx1定义为治疗再生障碍性贫血的新治疗靶点。

Project Summary Aortic aneurysms (AA) represent a significant clinical problem with a high risk of aortic rupture leading to sudden death. Currently, there are no medical therapies available to treat aneurysms and a clear understanding of the pathobiology of AA formation is key to develop therapeutic pharmacological approaches. Recent studies reveal that ATP can be released by cells in a controlled manner through pannexin 1 (Panx1) channels to signal through purinergic P2X or P2Y receptors. ATP is a nucleotide released in large amounts after tissue injury such as AA and serves as a “danger signal” to mediate inflammation. Our data suggest that Panx1 on endothelial cells (ECs) is an important mediator of vascular inflammation in a murine model of abdominal AA (AAA) and can be a major source of extracellular ATP. The expression of Panx1 is highest in the arterial network especially in the aortic endothelium. The scientific premise of this proposal focuses on the crosstalk between aortic endothelium, smooth muscle cells and relevant immune cells to delineate Panx1- mediated signaling in AAA progression. Thus, this proposal will test the overall hypothesis that EC Panx1 signaling is a major, early inflammatory mediator of the signaling cascade via release of ATP resulting in smooth muscle cell activation, leukocyte infiltration and vascular inflammation. Using novel inducible cell- specific genetic knockout animals, specific pharmacological Panx1 inhibitors and P2X/P2Y antagonists, we will delineate this previously unknown mechanism of AAA pathobiology. Aim 1 will determine if EC Panx1 signaling mediates AAA via ATP release and its crosstalk with aortic smooth muscle cells as well as to determine whether the P2X7 receptor is a major determinant of AAA. We will also investigate if Panx1 inhibition can treat preformed AAAs in the murine models. Aim 2 will determine if Panx1 signaling mediates leukocyte activation and infiltration during AAA. The role of Panx1 and specific purinergic receptors on macrophages will be deciphered as well as whether Panx1 mediates neutrophil transendothelial migration. Aim 3 will determine if pharmacologic inhibition of Panx1 or specific P2 receptors will treat AAA using a chronic inflammatory, large animal porcine AAA model. Our studies will provide novel insight into mechanisms of molecular signaling interactions between aortic endothelial cells, smooth muscle cells, and immune cells (macrophages and neutrophils), to define Panx1 as a novel therapeutic target for the treatment of AAs.