Redox-mediated regulation of pattern-recognition-receptor signaling in intestinal epithelial cells

项目总结 肠上皮是一种重要的粘膜屏障，它调节肠道之间的沟通。 腔内环境和免疫系统。有几条证据表明，稳定的活性氧 物种(ROS)在调节粘膜表面的细胞信号方面发挥着重要作用，无论是对 微生物环境和肠道炎症。稳定的ROS，如过氧化氢(H2O2)可以 由上皮细胞通过NADPH氧化酶家族(例如NOX1)或从其他 环境来源，如细菌。H_2O_2通过氧化修饰调节细胞信号转导 靶向蛋白质上的半胱氨酸残基，改变下游功能。然而，到底是什么信号蛋白 炎症过程中受ROS影响的通路知之甚少，可能提供了关键 了解炎症性肠病的发病机制和发展的信息 追踪疾病活动的生物标记物。 我们最近的数据显示，NOX1产生的过氧化氢可以通过水通道(AQP3)转运 在调节上皮性环境反应中起重要作用。我们的研究还表明， 上皮细胞信号，响应模式识别-受体‘危险’信号，如白细胞介素1β (IL-1b)，也是依赖H_2O_2的。为了进一步研究在存在的情况下选择性氧化的蛋白质 在IL-1b方面，我们对小鼠原代肠道上皮细胞进行了氧化还原蛋白质组学研究。我们发现了几个 依赖于NOX1和AQP3的选择性氧化的候选蛋白质，包括 过氧化还蛋白6(PRDX6)--一种已知的多功能氧化还原敏感蛋白。本R03提案的目标1将 因此，检验PRDX6功能对上皮模式识别受体重要的假设 发信号。Aim 2采用蛋白质组学方法识别人类疾病中的关键氧化还原修饰蛋白 使用健康人和健康人来源的结肠素研究模式识别受体反应 患有炎症性肠病的个人。这些研究的主要目标是确定新的氧化还原- 炎性危险信号转导过程中肠上皮细胞依赖的信号转导途径及其应用 这一数据为开发治疗粘膜炎症性疾病的新方法提供了依据。

PROJECT SUMMARY The intestinal epithelium is a critical mucosal barrier that mediates communication between the intestinal luminal environment and the immune system. Several lines of evidence suggest that stable reactive oxygen species (ROS) play an important role in regulating cell signaling at mucosal surfaces, both in response to the microbial environment and in gut inflammation. Stable ROS such as hydrogen peroxide (H2O2) can be generated by epithelial cells through the NADPH oxidase enzyme family (e.g. NOX1) or from other environmental sources such as bacteria. H2O2 modulates cellular signaling via oxidative modifications of target cysteine residues on proteins, altering downstream functions. However, exactly what signaling proteins and pathways are impacted by ROS during inflammation is poorly understood and may provide key information in understanding the pathogenesis of inflammatory bowel diseases and the development of biomarkers to track disease activity. Our recent data shows that NOX1-generated H2O2 can be transported through aquaporin channels (AQP3) and is important in mediating epithelial environmental responses. Our studies have also shown that epithelial signaling, in response to pattern-recognition-receptor ‘danger’ signals such as interleukin-1 beta (IL-1b), is also H2O2-dependent. To further investigate proteins that are selectively oxidized in the presence of IL-1b we carried out redox proteomics of mouse primary intestinal epithelial cells. We discovered several candidate proteins that are selectively oxidized in a NOX1 and AQP3-dependent manner, including Peroxiredoxin 6 (PRDX6) - a known multifunctional redox-sensitive protein. Aim 1 of this R03 proposal will therefore test the hypothesis that PRDX6 function is important for epithelial pattern-recognition-receptor signaling. Aim 2 takes a proteomics approach to identify key redox-modified proteins in human disease by investigating pattern-recognition-receptor responses using colonoids derived from healthy individuals and individuals with inflammatory bowel disease. The main goals of these studies are to identify novel redox- dependent signaling pathways in intestinal epithelial cells during inflammatory danger signaling and to use this data to develop novel therapeutic approaches for mucosal inflammatory diseases.