Regulation of endothelial NADPH oxidase by the cytoskeleton

虽然血管和吞噬NADPH氧化酶之间的差异尚未确定，活性氧（ROS）已成为重要的调节分子，其作为关键的第二信使调节参与内皮细胞生长，迁移，粘附和屏障功能的信号转导途径。虽然肌动蛋白细胞骨架已被牵连在中性粒细胞的吞噬作用和氧化爆发，很少有人知道关于内皮NAD[P]H氧化酶组装和激活的肌动蛋白细胞骨架的作用。我们的初步研究表明，急性高氧介导的NAD[P]H氧化酶的激活和超氧化物的产生增强皮质肌动蛋白细胞骨架重排，磷酸化肌球蛋白轻链，小G蛋白和磷脂酸的调节。 我们假设急性高氧诱导的内皮NAD[P]H氧化酶激活是通过调节皮质肌动蛋白细胞骨架重塑的信号转导途径和促进氧化酶子组分的组装来介导的。以下具体目标将研究急性高氧，肌动蛋白细胞骨架重塑和NAD[P]H氧化酶组装和激活在人肺动脉内皮细胞在没有细胞毒性的情况下之间的关系。SA #1：将研究连接NAD[P]H氧化酶活化中肌动蛋白细胞骨架重塑的途径; SA#2：将表征肌球蛋白轻链磷酸化在NAD[P]H氧化酶活化中的作用; SA#3：将定义corneum和coronin在内皮NAD[P]H氧化酶活化中的作用，SA#4：将表征磷脂酶D / 内皮细胞NAD[P]H氧化酶活化中的磷脂酸信号传导。了解肌动蛋白细胞骨架重塑在NAD[P]H氧化酶组装和激活中的作用将有助于开发靶向治疗，以调节ROS诱导的信号传导，预防肺损伤和内皮功能障碍。

While differences between vascular and phagocytic NADPH oxidase are yet to be identified, reactive oxygen species (ROS) have emerged as important regulatory molecules which function as critical second messengers modulating signal transduction pathways involved in endothelial cell growth, migration, adhesion and barrier function. While actin cytoskeleton has been implicated in phagocytosis and oxidative burst in neutrophils, very little is known regarding the role of actin cytoskeleton in endothelial NAD[P]H oxidase assembly and activation. Our preliminary studies demonstrate that acute hyperoxia-mediated activation of NAD[P]H oxidase and enhanced production of superoxide is regulated by cortical actin cytoskeleton rearrangement, phosphorylated myosin light chain, small G-proteins and phosphatidic acid. We hypothesize that acute hyperoxia-induced endothelial NAD[P]H oxidase activation is mediated by signal transduction pathways regulating cortical actin cytoskeleton remodeling and by facilitating the assembly of the oxidase sub-components. The following specific aims will investigate the relationship between acute hyperoxia, actin cytoskeletal remodeling and NAD[P]H oxidase assembly and activation in human pulmonary artery endothelial cells in the absence of cytotoxicity. SA#1: Will investigate pathways linking actin cytoskeleton remodeling in NAD[P]H oxidase activation; SA#2: Will characterize the role of myosin light-chain phosphorylation in NAD[P]H oxidase activation; SA#3: Will define the role of cortactin and coronin in endothelial NAD[P]H oxidase activation and SA#4: Will characterize the role of phospholipase D / phosphatidic acid signaling in endothelial NAD[P]H oxidase activation. An understanding of the role of actin cytoskeletal remodeling in NAD[P]H oxidase assembly and activation will allow development of targeted therapies to modulate ROS-induced signaling and prevent lung injury and endothelial dysfunction.