The intestinal epithelium serves as a dynamic barrier to the environment and integrates a variety of signals, including those from metabolites, commensal microbiota, immune responses and stressors upon ageing. The intestine is constantly challenged and requires a high renewal rate to replace damaged cells in order to maintain its barrier function. Essential for its renewal capacity are intestinal stem cells, which constantly give rise to progenitor cells that differentiate into the multiple cell types present in the epithelium. Here, we review the current state of research of how metabolism and ageing control intestinal stem cell function and epithelial homeostasis. We focus on recent insights gained from model organisms that indicate how changes in metabolic signalling during ageing are a major driver for the loss of stem cell plasticity and epithelial homeostasis, ultimately affecting the resilience of an organism and limiting its lifespan. We compare findings made in mouse and Drosophila and discuss differences and commonalities in the underlying signalling pathways and mechanisms in the context of ageing.

中文翻译：

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衰老，新陈代谢和肠道。

肠上皮是对环境的动态屏障，并整合了各种信号，包括来自代谢产物，共生微生物，免疫反应和衰老时的应激源的信号。肠道不断受到挑战，需要很高的更新率来替换受损的细胞，以维持其屏障功能。肠干细胞对其更新能力至关重要，它会不断产生分化为上皮细胞的多种细胞的祖细胞。在此，我们回顾了代谢和衰老如何控制肠道干细胞功能和上皮稳态的研究现状。我们关注从模型生物中获得的最新见解，这些研究表明衰老过程中代谢信号的变化是干细胞可塑性和上皮稳态丧失的主要驱动力，最终影响了生物的弹性并限制了其寿命。我们比较在老鼠和果蝇并讨论了衰老过程中潜在信号通路和机制的差异和共性。