The role of NFATc3 in altered hypoxic pulmonary vasoconstriction during acute lung injury

肺部炎症和低氧血症是急性呼吸道感染患者死亡的主要危险因素 窘迫综合症，一种以死亡率为特征的疾病，据估计可能会超过 40%。败血症是一种严重的炎症性疾病，是#年发病率和死亡率的主要原因 这些病人。气体交换受损和低氧血症定义了这种严重的呼吸系统疾病和 肺微环境中的通风和灌流的匹配是获得充足气体的关键 交换。受损的缺氧性肺血管收缩(HPV)导致通气性和 血流灌注不匹配导致低氧血症和HPV受损与多发性 与炎症相关的肺部疾病，包括败血症和急性肺损伤。 目前的建议集中在激活的T细胞核因子(NFAT)在 急性肺损伤和炎症期间受损的缺氧性肺血管收缩(HPV)。 NFAT是一种转录因子，在磷酸被切割后移位到细胞核 钙调神经磷酸酶，作为钙依赖的磷酸酶，它在转录上调节许多 基因靶标。NFAT与多种炎症性疾病过程有关，包括 脓毒症和ALI的实验动物模型。TRPC渠道是 对肺血管反应性至关重要的细胞内钙内流和信号转导。我们的 初步数据表明，内毒素诱导的肺损伤导致NFAT激活和受损 缺氧性肺血管收缩，可能是由于TRPC通道下调所致。我们 假设急性肺部炎症导致HPV受损和TRPC下调 通道表达和功能导致ARDS患者低氧血症。发炎- NFAT介导的表观遗传修饰导致TRPC通道下调 它可以作为实验动物模型和体内制剂的靶点。 我们将使用特定的目标来定义这种关系。在目标1中，我们将确定 肺组织炎症和NFAT激活对大鼠肺血管平滑肌细胞和细胞周期的影响 肺血管反应性。在目标2中，我们将确定负责 NFAT激活引起的PASMC和肺血管反应性的变化。在《目标3》中，我们将 确定炎症、NFAT激活和表观遗传修饰的影响 在体小鼠制备。 除了研究提案外，还提出了一项详细的培训计划，以便 促进作为一名内科科学家的成功职业发展。我们描述了如何 导师将培养研究方法、写作发展和职业发展方面的技能 通过受保护的研究时间、授课学习、同行认可、校内和校外 培训、著作权、合作和未来赠款发展。我们已经提出了一个分级的 最初至少占75%时间投入的研究活动的结构 非常重视课程作业和学习机会，这逐渐演变为 在研究项目、手稿出版和R01开发上花费了更多的时间。 我们的长期目标是明确HPV在肺部炎症中受损的机制。 为了寻找新的分子靶点以增强V/Q匹配和气体交换 阿龙。通过这项建议，我希望加强我在肺部疾病方面的知识和技能 血管疾病研究，以促进我作为独立调查员的发展 和成功的内科医生兼科学家。

Lung inflammation and hypoxemia are major risk factors for mortality in acute respiratory distress syndrome, a disorder characterized by mortality that by some estimates can exceed 40%. Sepsis, a severe inflammatory disorder, is the primary cause of morbidity and mortality in these patients. Impaired gas exchange and hypoxemia define this severe respiratory illness and matching of ventilation and perfusion in the lung microenvironment is crucial for adequate gas exchange. Impaired hypoxic pulmonary vasoconstriction (HPV) results in ventilation and perfusion mismatching leading to hypoxemia and impaired HPV has been implicated in multiple pulmonary diseases associated with inflammation, including sepsis and acute lung injury. The current proposal focuses on the role of nuclear factor of activated T-cells (NFAT) in impaired hypoxic pulmonary vasoconstriction (HPV) during acute lung injury and inflammation. NFAT is a transcription factor that translocates to the nucleus after phosphate cleavage by calcineurin, as calcium dependent phosphatase, where it transcriptionally regulates numerous gene targets. NFAT has been implicated in multiple inflammatory disease processes including experimental animal models of sepsis and ALI. TRPC channels are an essential factor in intracellular calcium influx and signaling that is crucial for pulmonary vasoreactivity. Our preliminary data suggests that LPS-induced lung injury leads to NFAT activation and impaired hypoxic pulmonary vasoconstriction, potentially due to downregulation of TRPC channels. We hypothesize that acute lung inflammation causes impaired HPV and downregulated TRPC channel expression and function leading to hypoxemia in ARDS patients. The inflammation- mediated TRPC channel downregulation is due to NFAT-mediated epigenetic modifications which can be targeted in experimental animal models and in vivo preparations. We will use specific aims in order to define this relationship. In Aim 1 we will determine the effects of lung inflammation and NFAT activation on pulmonary artery smooth muscle cells and pulmonary vasoreactivity. In Aim 2 we will determine the epigenetic mechanisms responsible for changes in the PASMC and pulmonary vasoreactivity due to NFAT activation. In Aim 3 we will determine the effects of inflammation, NFAT activation, and epigenetic modifications in a novel in vivo mouse preparation. In addition to the research proposal, a detailed training plan has been proposed in order to facilitate the development of a successful career as a physician-scientist. We describe how mentorship will foster skills in research methods, writing development, and career advancement through protected research time, didactic learning, peer recognition, intramural and extramural training, authorship, collaboration and future grant development. We have proposed a graded structure in which research activities which represent at least 75% time commitment initially have a strong emphasis on course work and learning opportunities which gradually evolves into more time spent on the research project, manuscript publication, and R01 development. Our long-term goals are to define the mechanisms of impaired HPV in lung inflammation in order to identify novel molecular targets to enhance V/Q matching and gas exchange in the lung. With this proposal I hope to strengthen my knowledge and technical skills in pulmonary vascular disease research in order to facilitate my development as an independent investigator and successful physician-scientist.