Beijing Advanced Innovation Center for Food Nutrition and Human Health, China Agricultural University, Beijing, P. R. China.
State Key Laboratory of Animal Nutrition, China Agricultural University, Beijing, P. R. China.
Eur J Immunol. 2022 Jun;52(6):856-868. doi: 10.1002/eji.202149401. Epub 2022 Apr 29.
The intestinal mucosal barrier is critical for the absorption of nutrients and the health of both humans and animals. Recent publications from clinical and experimental studies have shown the importance of the nutrients-bacteria-host interaction for the intestinal homeostasis. Dysfunction of these interactions has been reported to be associated with metabolic disorders and development of intestinal diseases such as the irritable bowel syndrome and inflammatory bowel diseases. Tryptophan and its metabolites, including kynurenine, kynurenic acid, and 5-hydroxytrptamine, can influence the proliferation of enterocytes, intestinal integrity, and immune response, as well as intestinal microbiota, therefore, regulating and contributing to the intestinal health. In this review, we highlight recent findings on the effect of tryptophan and its metabolites on the mucosal barrier and intestinal homeostasis and its regulation of innate immune response. Moreover, we present the signaling pathways related to Trp metabolism, such as mammalian target of rapamycin, aryl hydrocarbon receptor, and pregnane X receptor, which contribute to the intestinal homeostasis and discuss future perspectives on spontaneous interference in host tryptophan metabolism as potential clinical strategies of intestinal diseases.
肠道黏膜屏障对于人类和动物的营养吸收和健康都至关重要。来自临床和实验研究的最新出版物表明，营养物质-细菌-宿主相互作用对于肠道内环境稳态的重要性。这些相互作用的功能障碍已被报道与代谢紊乱和肠道疾病（如肠易激综合征和炎症性肠病）的发展有关。色氨酸及其代谢物，包括犬尿氨酸、犬尿喹啉酸和 5-羟色胺，能够影响肠细胞的增殖、肠道完整性和免疫反应以及肠道微生物群，从而调节和促进肠道健康。在这篇综述中，我们强调了色氨酸及其代谢物对黏膜屏障和肠道内环境稳态的影响，以及它们对固有免疫反应的调节作用。此外，我们还介绍了与 Trp 代谢相关的信号通路，如哺乳动物雷帕霉素靶蛋白、芳香烃受体和孕烷 X 受体，这些信号通路有助于肠道内环境稳态，并讨论了作为肠道疾病潜在临床策略的自发干扰宿主色氨酸代谢的未来前景。
