Evaluating the effect of zonulin-mediated intestinal trafficking on gastrointestinal macrophages and their function on gastric motility

项目摘要/摘要 胃动力障碍影响40%-80%的危重儿童，并与显著的发病率和更多的 致命性。关于危重病儿童胃动力障碍的机制存在知识空白， 限制这一队列的治疗选择。胃肠(GI)巨噬细胞调节胃运动和 已被证明对它们的功能具有微生物组依赖的变化。依赖微生物组的变化 巨噬细胞的激活是由微生物产物的跨上皮肠道运输所介导的。佐林市是 一种蛋白质，可增加微生物产品的跨上皮运输。Zonrin的表达模式包括- 在Zonlin转基因小鼠(Ztm)中，具有促炎症巨噬细胞的代谢紊乱和激活作用。最重要的是- 在表达zonlin的CALY患病儿童中，我们已经在ZTM小鼠中发现了胃动力障碍。我们的中央- 假说是佐林在炎症条件下上调，增加了跨上皮转运 来自改变的微生物群的微生物产物，它激活与胃运动障碍相关的巨噬细胞。 在目标1中，我们评估了zonlin介导的跨上皮肠道转运的增加是否由于系统- IC炎症导致与胃动力障碍相关的巨噬细胞的功能失调和激活。我们会 在Ztm小鼠身上完成目标1，并使用zonlin抑制剂。在目标2a中，我们将确定MI-2中的差异 肠道跨上皮转运指标与胃动力关系的研究 有无产生zonlin的等位基因的人。胃肠道巨噬细胞差异的直接检测 TITENS是不可行的。因此，在目标2b中，我们使用了粪便材料移植的翻译小鼠模型。 来自AIM 2a的患者，以检查患有和不患有小带的患者的微生物区系是否存在差异- LIN产生等位基因和胃动力障碍导致小鼠巨噬细胞激活和胃动力障碍。 这一建议填补了我们对危重疾病胃动力障碍机制的理解的知识空白。 我们的长期目标是寻找新的诊断标记物和治疗靶点。 Cal疾病，这可能会影响这一队列的临床结果。这份提案详细说明了一个为期四年的项目，在这个项目中 马丁内斯博士将在临床翻译研究方面获得经验，并在胃肠道生理学、粘膜免疫和胃肠道疾病方面获得专业知识。 动物学、宿主-微生物组相互作用和神经-肠道系统。这些教育机会， 围绕着理想的研究环境和与马丁内斯博士合作的成熟的指导团队将 为她申请NIH R01拨款做好准备，并促进她成为一名独立学者 职业生涯。

Project Summary/ Abstract Gastric dysmotility affects 40-80% of critically ill children and is associated with significant morbidity and mor- tality. There are knowledge gaps regarding the mechanisms for gastric dysmotility in critically ill children, which limit the therapeutic options for this cohort. Gastrointestinal (GI) macrophages regulate gastric motility and have been shown to have microbiome-dependent changes on their function. Microbiome-dependent changes on macrophage activation are mediated by trans-epithelial intestinal trafficking of microbial products. Zonulin is a protein that increases trans-epithelial trafficking of microbial products. Models of zonulin expression, includ- ing a Zonulin transgenic mouse (Ztm), have dysbiosis and activation of pro-inflammatory macrophages. In criti- cally ill children who express zonulin and in Ztm mice we have identified gastric dysmotility. Our central hy- pothesis is that zonulin upregulation under conditions of inflammation, increases trans-epithelial trafficking of microbial products from an altered microbiome which activate macrophages associated with gastric dysmotility. In Aim 1 we evaluate whether zonulin-mediated increases in trans-epithelial intestinal trafficking due to system- ic inflammation result in dysbiosis and activation of macrophages associated with gastric dysmotility. We will complete Aim 1 with Ztm mice and the use of a zonulin inhibitor. In Aim 2a, we will identify differences in mi- crobiome composition and markers of trans-epithelial intestinal trafficking in relation to gastric motility in pa- tients with and without the zonulin-producing allele. Direct examination of GI macrophage differences in pa- tients is not feasible. Therefore, in Aim 2b, we employ a translational mouse model of fecal material transplant from patients in Aim 2a to examine whether differences in microbiota from patients with and without the zonu- lin-producing allele and gastric dysmotility result in macrophage activation and gastric dysmotility in the mice. This proposal fills a knowledge gap in our understanding of mechanisms for gastric dysmotility in critical illness. Our long-term goal is to identify novel diagnostic markers and therapeutic targets for gastric dysmotility in criti- cal illness, which can impact clinical outcomes for this cohort. This proposal details a four-year project in which Dr. Martinez will gain experience in clinical-translational research and expertise in GI physiology, mucosal im- munology, host-microbiome interactions and the neuro-enteric system. These educational opportunities, the surrounding ideal research environment and established mentoring team that is working with Dr. Martinez will prepare her to apply for a NIH R01 grant and promote her advancement towards an independent academic career.