RHO-ASSOCIATED KINASE-DEPENDENT CYTOSKELETAL AND TIGHTJUNCTION DYSREGULATION IN NECROTIZING ENTEROCOLITIS

项目摘要/摘要： 坏死性小肠结肠炎(NEC)是新生儿最常见的胃肠道急症，影响7%的新生儿 住进新生儿重症监护室的病人。尽管进行了多年的研究，但在理解上仍存在差距 疾病的基本病理生理学，以及缺乏新的治疗方法。Rho激酶(摇滚) 是丝氨酸/苏氨酸激酶，参与多种细胞过程，包括调节紧密连接 功能，肌动蛋白细胞骨架收缩，炎性细胞因子和细胞死亡。我们和其他人，之前 证实了这些通路与NEC的病理生理学相关。本R03的目标 建议确定岩石活化的机制(S)，确定岩石在 实验NEC，并确定岩石抑制限制NEC进展的机制。这个 中心假设是氧化应激和内毒素诱导ROCK激活，导致细胞骨架收缩 紧密连接降解，增强粘膜和全身炎症及上皮细胞凋亡。如果这个 假设是正确的，那么摇滚抑制将保护这些影响和NEC。为了测试这一点 假设，我们将研究通过ROCK通路的信号对紧密连接蛋白、上皮细胞的影响 实验性NEC的通透性、炎症和细胞凋亡。此应用程序的目标是定义 岩石介导的分子相互作用，直接上皮细胞功能在NEC。这些研究将有 强大的力量，因为它们将在体外、肠道、NEC的体内模型以及人类体内进行 患有和不患有NEC的婴儿的肠道样本。我们将确定是否抑制岩石途径 (通过药物和遗传方法)可以稳定紧密的连接，最大限度地减少炎症，减少 细胞死亡，并影响实验性NEC的转归和存活。这些发现将建立在我的 目前的研究，并对人类健康有重大的积极影响，通过提供一个新的理解 NEC过程中肠上皮屏障功能的调控机制。

PROJECT SUMMARY/ ABSTRACT: Necrotizing enterocolitis (NEC) is the most common gastrointestinal emergency of newborns, and affects 7% of patients admitted to a neonatal intensive care unit. Despite years of research there is a gap in the understanding of the underlying pathophysiology of disease, and a lack of novel therapeutic approaches. Rho kinases (ROCK) are serine/ threonine kinases and are involved in multiple cellular processes including regulating tight junction function, actin cytoskeleton contraction, inflammatory cytokines and cell death. We and others, have previously demonstrated the relevance of these pathways to the pathophysiology of NEC. The objectives of this R03 proposal are to define mechanism(s) of ROCK activation, identify molecular pathways targeted by ROCK during experimental NEC and to determine the mechanisms by which ROCK inhibition limits NEC progression. The central hypothesis is that oxidative stress and LPS induce ROCK activation, resulting in cytoskeletal contraction and tight junction degradation that enhances mucosal and systemic inflammation and epithelial apoptosis. If this hypothesis is correct then ROCK inhibition will be protective against these effects and NEC. To test this hypothesis, we will examine the effects of signaling through ROCK pathway on tight junction proteins, epithelial permeability, inflammation and apoptosis during experimental NEC. The objective of this application is to define the ROCK-mediated molecular interactions that direct epithelial function during NEC. These studies will have great power since they will be performed in vitro, in enteroids, and in vivo models of NEC as well as in human intestinal samples from infants with and without NEC. We will determine whether inhibition of the ROCK pathway (by pharmacological and genetic approaches) can stabilize tight junctions and minimize inflammation, decrease cell death, and influence the outcomes and survival in experimental NEC. These findings will build upon my current studies, and have a significant positive impact on human health by providing a new understanding of the mechanisms governing epithelial intestinal barrier function during NEC.