Inflammatory bowel disease (IBD) is a chronic inflammatory disorder of the gastrointestinal tract resulting from the homeostasis imbalance of intestinal microenvironment, immune dysfunction, environmental and genetic factors, and so on. This disease is associated with multiple immune cells including regulatory T cells (Tregs). Tregs are a subset of T cells regulating the function of various immune cells to induce immune tolerance and maintain intestinal immune homeostasis. Tregs are correlated with the initiation and progression of IBD; therefore, strategies that affect the differentiation and function of Tregs may be promising for the prevention of IBD-associated pathology. It is worth noting that tryptophan (Trp) metabolism is effective in inducing the differentiation of Tregs through microbiota-mediated degradation and kynurenine pathway (KP), which is important for maintaining the function of Tregs. Interestingly, patients with IBD show Trp metabolism disorder in the pathological process, including changes in the concentrations of Trp and its metabolites and alteration in the activities of related catalytic enzymes. Thus, manipulation of Treg differentiation through Trp metabolism may provide a potential target for prevention of IBD. The purpose of this review is to highlight the relationship between Trp metabolism and Treg differentiation and the role of this interaction in the pathogenesis of IBD.

中文翻译：

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色氨酸代谢，调节性T细胞和炎症性肠病：小型回顾。

炎症性肠病（IBD）是由肠道微环境的动态平衡失衡，免疫功能障碍，环境和遗传因素等导致的胃肠道慢性炎症性疾病。该疾病与包括调节性T细胞（Tregs）在内的多种免疫细胞有关。Treg是T细胞的子集，调节各种免疫细胞的功能，以诱导免疫耐受并维持肠道免疫稳态。Tregs与IBD的发生和发展相关。因此，影响Tregs分化和功能的策略对于预防IBD相关病理可能是有希望的。值得注意的是，色氨酸（Trp）代谢可有效地通过微生物群介导的降解和犬尿氨酸途径（KP）诱导Treg的分化，这对于维持Treg的功能很重要。有趣的是，IBD患者在病理过程中显示出Trp代谢紊乱，包括Trp及其代谢产物浓度的变化以及相关催化酶活性的改变。因此，通过Trp代谢操纵Treg分化可能为预防IBD提供潜在的靶点。这篇综述的目的是强调Trp代谢和Treg分化之间的关系，以及这种相互作用在IBD发病机理中的作用。通过Trp代谢控制Treg分化可能为预防IBD提供潜在的靶点。这篇综述的目的是强调Trp代谢和Treg分化之间的关系，以及这种相互作用在IBD发病机理中的作用。通过Trp代谢控制Treg分化可能为预防IBD提供潜在的靶点。这篇综述的目的是强调Trp代谢和Treg分化之间的关系，以及这种相互作用在IBD发病机理中的作用。