The role of local iron homeostasis in inflammatory bowel disease

项目摘要 贫血是炎症性肠病（IBD）最常见的并发症。 IBD 相关贫血是 通常难以治疗，而且铁稳态失调在 IBD 病理学中的作用尚不清楚。 因此，更好地了解肠道铁稳态可能有助于新的治疗策略 IBD 和 IBD 相关贫血。贫血和炎症与铁调素激素直接相关，铁调素是一种激素。 通过铁转运蛋白铁转运蛋白严重抑制细胞内储存的铁释放。在新数据中，我 确定树突状细胞 (DC) 产生的铁调素对于肠后组织愈合至关重要 炎症，铁调素在儿科克罗恩病发炎组织中的树突状细胞中高表达 （CD）患者。此外，铁调素通过限制组织相关细菌的铁利用率来促进愈合 肠髓细胞中的铁螯合。本研究计划的重点是调查 假设在慢性肠道炎症和慢性肠道炎症中，肠道铁稳态由铁调素调节 儿科克罗恩病患者促进组织愈合。在目标 1 中，我将探讨铁调素和 铁转运蛋白在慢性肠道炎症、铁稳态和骨髓细胞生物学中的作用。在目标 2 中，我将定义 人类铁调素和铁转运蛋白表达的调节，我将探讨该轴之间的相关性， 铁稳态和 TNF 阻滞剂治疗儿科克罗恩病。我将采用创新的技术方法 来表征小鼠和 IBD 患者样本中的解剖铁水平，我将开发新的遗传工具来 研究铁调素和铁转运蛋白在骨髓细胞中的作用。总的来说，这些研究的结果将定义 IBD 中肠道铁稳态的调节和功能意义，有可能定义新的 儿科 CD 患者的治疗策略。

PROJECT ABSTRACT Anemia is the most common complication of inflammatory bowel disease (IBD). IBD-associated anemia is often refractory to treatment, and the role of dysregulated iron homeostasis in IBD pathology is unknown. Accordingly, a better understanding of intestinal iron homeostasis may facilitate new therapeutic strategies for IBD and IBD-associated anemia. Anemia and inflammation are directly linked by the hormone hepcidin, which critically inhibits iron release from intracellular stores via the iron transporter ferroportin. In new data, I've identified that hepcidin produced by dendritic cells (DCs) is critical for tissue healing after intestinal inflammation, and that hepcidin is highly expressed by DCs in inflamed tissues of pediatric Crohn's disease (CD) patients. Moreover, hepcidin promoted healing by limiting iron availability to tissue-associated bacteria via iron sequestration in intestinal myeloid cells. The focus of this research proposal is to investigate the hypothesis that intestinal iron homeostasis is regulated by hepcidin in chronic intestinal inflammation and in pediatric Crohn's patients to promote tissue healing. In Aim 1, I will interrogate the role of hepcidin and ferroportin in chronic intestinal inflammation, iron homeostasis, and myeloid cell biology. In Aim 2, I will define the regulation of hepcidin and ferroportin expression in humans, and I will probe correlations between this axis, iron homeostasis, and TNF blockers in pediatric Crohn's disease. I will employ innovative technical approaches to characterize anatomical iron levels in mice and IBD patient samples, and I will develop new genetic tools to study the role of hepcidin and ferroportin in myeloid cells. Collectively, results from these studies will define the regulation and functional significance of intestinal iron homeostasis in IBD, with the potential to define novel therapeutic strategies for pediatric CD patients.