Genetics, Epigenetics, and Post-translational Modifications and the Development of Ventilator-Induced Lung Injury (VILI)

计划摘要 危重病患者急性呼吸衰竭的机械通气救命干预 呼吸窘迫综合征(ARDS)，也会造成过度的机械应激，加剧肺损伤， 被称为呼吸机诱导肺损伤(VILI)的综合征。VILI和ARDS的病理生物学有许多共同之处 炎症特征，包括内皮细胞(EC)丢失引起的肺血管通透性增加 屏障完整性。对Vili病理生物学的见解一直在增加，还没有实现可行的治疗方法。这个PPG 集中于增加我们对以下方面的理解：i)传递以下效应的转录因子 过度机械应激；ii)导致EC损伤的分子信号通路，包括最初的激活 一个机械敏感的钙调节受体，瞬时受体电位阳离子通道V亚家族成员4 (TRPV4)；iii)影响VILI中关键信号通路的翻译后修饰(PTM) 反应；iv)涉及VILI反应的关键目标基因的遗传和表观遗传影响；v)新颖 VILI的治疗策略。构成每个项目重点的关键新基因通过以下方式确定 我们的基因组密集型方法，并因其对VILI谱的贡献而被选择 对VILI诱导的肺部炎症、血管通透性增加和损伤的反应(项目1和2)； 恢复肺血管屏障完整性的VILI解决方案(项目3)。这些战略是综合的 涵盖我们的三个PPG项目，并代表了这个PPG的主题基础。研究将会是 由一群才华横溢、互动式的翻译科学家主持。项目1将检查核因子-κB- VILI下调SOX18表达的依赖机制(包括蛋白质硝化) 关键的肺血管屏障保护性转录因子(TF)和关键的紧密连接蛋白claudin 5。 机械敏感受体TRPV4对线粒体ROS和机械应激相关的影响 将探索诸如HIF2α之类的TFS。项目2将扩展关于Sected的关键作用的新见解 胞外NAMPT(ENAMPT)，一种烟酰胺磷酸核糖转移酶，在VILI和ARDS中。过份 机械应激诱导NAMPT表达及与Toll样受体4(Toll样受体4)连接诱导NF-κB的表达 信号转导与炎性肺损伤。项目2将询问NAMPT分泌的新机制， NAMPT/TLR4单核苷酸多态的影响，以NAMPT和TLR4为治疗靶点。项目3将审问 机械应激介导的神经鞘氨醇1-磷酸受体表达的遗传和表观遗传调控 (S1PR1，S1PR3)及VILI诱导的Rac1和RhoA GTP酶硝化在肺血管屏障中的作用 监管。从各个项目之间的互动中产生的协同效应，以及与我们的科学 拥有令人羡慕的分子生物学(B)、遗传流行病学(B)、临床前模型 疾病(C)和蛋白质化学和生物物理学(D)将推进我们的规划方法，并促进 开发新的个体化治疗方法以减轻VILI，特别是在ARDS高危人群中。

PROGRAM SUMMARY Mechanical ventilation, a life-saving intervention in critically ill patients with respiratory failure due to acute respiratory distress syndrome (ARDS), also creates excessive mechanical stress that augments lung injury, a syndrome known as ventilator-induced lung injury (VILI). The pathobiology of VILI and ARDS share many inflammatory features including increases in lung vascular permeability due to loss of endothelial cell (EC) barrier integrity. Insights into VILI pathobiology have been incremental with no viable therapies realized. This PPG intensely focuses on increasing our understanding of: i) the transcription factors that relay the effects of excessive mechanical stress; ii) the molecular signaling pathways that lead to EC injury, including initial activation of a mechanosensitive Ca2+-regulatory receptor, transient receptor potential cation channel subfamily V member 4 (TRPV4); iii) post translational modifications (PTMs) that influence key signaling pathways involved in VILI responses; iv) genetic and epigenetic influences in key target genes involved in VILI responses; and v) novel therapeutic strategies for VILI. The key novel genes that comprise the focus of each Project were identified by our genomic–intensive approaches and selected for their capacity to contribute to a spectrum of VILI responses from VILI-induced lung inflammation, increased vascular permeability and injury (Projects #1 and #2); to VILI resolution with restoration of lung vascular barrier integrity (Project #3). These strategies are integrated across our three PPG projects and represent the thematic underpinnings of this PPG. Studies will be conducted by an outstanding group of gifted and interactive translational scientists. Project #1 will examine the NF-κB- dependent mechanisms (including protein nitration) by which VILI downregulates expression of SOX18, a critical lung vascular barrier-protective transcription factor (TF), and the key tight junction protein, claudin 5. The influence of the mechanosensitive receptor, TRPV4 on mitochondrial ROS and mechanical stress-associated TFs such as HIF2α will be explored. Project #2 will extend novel insights regarding the critical role of secreted extracellular NAMPT (eNAMPT), a nicotinamide phosphoribosyltransferase, in VILI and ARDS. Excessive mechanical stress induces NAMPT expression and eNAMPT ligates TLR4 (Toll-like receptor 4) to induce NF-κB signaling and inflammatory lung injury. Project #2 will interrogate novel mechanisms of NAMPT secretion, the influence of NAMPT/TLR4 SNPs, and NAMPT and TLR4 as therapeutic targets. Project #3 will interrogate genetic and epigenetic regulation of mechanical stress-mediated sphingosine 1-phosphate receptor expression (S1PR1, S1PR3) and the role of VILI-induced nitration of Rac1 and RhoA GTPases in lung vascular barrier regulation. The synergy derived from the interaction between individual Projects, as well as with our scientific Cores, with enviable expertise in molecular biology (B), genetic epidemiology (B), pre-clinical models of disease (C), and protein chemistry & Biophyics (D), will advance our programmatic approaches and promote the development of novel, individualized therapies to attenuate VILI especially in populations at risk for ARDS.