Intestinal Homeostasis Induced by Commensals

摘要 虽然包括P-gp和MRP 2在内的多药耐药转运蛋白通常被研究其在肿瘤中的作用， 在输出药物和外来化合物的细胞的作用，我们的研究表明，这些流出 在肠上皮细胞顶端表面表达的泵提供了一个关键环节， 粘膜屏障和免疫系统的前哨功能之间的通信。 了解P-gp/eCB抗炎臂是如何调节的将提供重要的见解 功能障碍如何促进肠道炎症，并帮助识别潜在的新的 治疗目标因为已知常驻微生物群有助于耐受性， 为了在健康的肠道中维持内稳态，我们旨在检验的中心假设是， 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，微生物群确实影响P-gp的表达和功能， 为进一步的因果研究奠定了独特的基础。此前没有数据表明 在微生物群和eCB或任何其他上皮脂质信号之间， 深入了解一个新系统。弥合这一差距可以帮助解释肠道细菌如何 稳定耐受状态以及特定途径元件的遗传修饰如何 使个体易患炎性肠病（IBD）。开始寻址 在本申请的目的1中，这些问题将在体外（包括人类结肠）结合联合收割机， 在体内鼠模型系统中，以及使用健康和UC患者粪便， 了解共同最大化P-gp表达和功能的微生物财团。目的 2旨在鉴定驱动P-gp表达活化的微生物代谢物， eCB分泌以维持肠上皮中的抗炎性。因此，在本发明中， 将进行转录组学和代谢物分析，以提供有关 微生物基因、基因簇及其代谢产物参与维持抗- 通过调节P-gp/eCB轴，在肠上皮中调节炎性张力。在目标3 我们将采用新的计算方法来揭示微生物间的网络反应， 以及能够诱导P-gp表达的稳定群落的生态结构。 总体而言，了解协调P-gp/eCB轴维持的途径 需要全面了解调节肠道内稳态的不同信号， 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-微生物相互作用。因此，这一建议将直接推动新的 生物学原理与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.