Intestinal Homeostasis Induced by Commensals

摘要 而包括P-gp和MRP2在内的多药耐药转运体通常被研究为 在从细胞输出药物和外来化合物方面的作用，我们的研究表明这些外流 在肠上皮细胞顶端表面表达的泵在 粘膜屏障的前哨功能与免疫系统之间的联系。 了解P-gp/ECB抗炎分支是如何受到监管的，将提供至关重要的见解 研究功能障碍如何促进肠道炎症并帮助识别潜在的新的 治疗靶点。因为居住的微生物群已知有助于耐受性和 在健康的肠道中的动态平衡，我们旨在测试的中心假设是正常的 微生物群积极驱动P-gp/ECB轴，以防止不必要的炎症。我们的飞行员 研究表明，微生物区系确实影响P-gp的表达和功能，提供一种 为进一步的因果关系研究奠定了独特的基础。此前没有数据显示两者之间存在联系 在微生物区系和ECB或任何其他上皮脂信号之间，很可能提供很好的 对一个新系统的洞察。弥合这一差距有助于解释共生细菌如何 稳定耐受状态以及特定途径元件的基因修饰如何 易患炎症性肠病(IBD)。开始寻址 在本申请的目标1中，这些问题将在体外结合(包括人类结肠癌)和 体内小鼠模型系统，以及使用健康的和UC患者的粪便，以更深入地 了解共同最大化P-gp表达和功能的微生物联合体。目标 2旨在确定驱动P-gp表达和P-gp表达激活的微生物代谢产物 ECB分泌维持肠道上皮的抗炎基调。因此， 将进行转录和代谢物分析，以提供有关 微生物基因、基因簇及其代谢产物与维持抗病毒活性有关 通过调节P-gp/ECB轴调节肠上皮炎性张力。在AIM 3中 我们将使用新的计算方法Will来揭示微生物间的网络响应 以及能够诱导P-gp表达的稳定群落的生态结构。 总而言之，协调P-gp/ECB轴维护的途径的知识 需要对调节肠道内环境平衡的不同信号有全面的了解， 多种信号是如何在复杂的肠道环境中整合的，以及 调节宿主与微生物的相互作用。因此，这一提议将直接推动小说 生物学原理和新的治疗干预策略的指导。

ABSTRACT While multidrug-resistance transporters including P-gp and MRP2 are generally studied for their role in exporting drugs and foreign compounds from the cell, our studies indicate that these efflux pumps expressed at the apical surface of intestinal epithelial cells provide a critical link in communication between sentinel functions of mucosal barriers and the immune system. Understanding how this P-gp/eCB anti-inflammatory arm is regulated will provide crucial insight into how dysfunction may promote intestinal inflammation and help identify potential new therapeutic targets. Because the resident microbiota is known to contribute to tolerance and homeostasis in the healthy intestine, the central hypothesis we aim to test is whether the normal microbiota actively drives the P-gp/eCB axis to prevent unnecessary inflammation. Our pilot studies indicate that the microbiota does influence P-gp expression and function, providing a unique foundation for further cause-effect studies. No data have previously demonstrated a link between the microbiota and eCBs or any other epithelial lipid signals, and may well provide great insight into a novel system. Bridging this gap could help explain how commensal bacteria can stabilize a state of tolerance and how genetic modification of specific pathway elements might predispose individuals to conditions of inflammatory bowel disease (IBD). To begin addressing these questions, in Aim 1 of this application will combine in vitro (including human colonoids) and in vivo murine model systems, as well as use healthy and UC patient stool, to more deeply understand the microbial consortia that collectively maximize P-gp expression and function. Aim 2 is designed to identify the microbial metabolites that drive activation of P-gp expression and eCB secretion to maintain an anti-inflammatory tone in the intestinal epithelium. Thus, transcriptomics and metabolite analyses will be performed to provide new information regarding microbial genes, gene clusters, and their metabolic products implicated in maintaining an anti- inflammatory tone in the intestinal epithelium through regulation of the P-gp/eCB axis. In Aim 3 we will employ novel computational methods will to uncover the inter-microbial network responses and the ecological structure of a stable community that is able to induce P-gp expression. Collectively, knowledge of the pathways that coordinate the maintenance of the P-gp/eCB axis will require a comprehensive understanding of distinct signals regulating intestinal homeostasis, how multiple signals are integrated in the complex intestinal environment, and pathways that modulate host-microbe interactions. Consequently, this proposal will directly advance novel biological principles with guidance of new therapeutic intervention strategies.