Indole and its derivatives are widespread across different life forms, functioning as signalling molecules in prokaryotes and with more diverse roles in eukaryotes. A majority of indoles found in the environment are attributed to bacterial enzymes converting tryptophan into indole and its derivatives. The involvement of indoles among lower organisms as an interspecies and intraspecies signal is well known, with many reports showing that inter-kingdom interactions involving microbial indole compounds are equally important as they influence defence systems and even the behaviour of higher organisms. This review summarizes recent advances in our understanding of the functional properties of indole and indole derivatives in diverse eukaryotes. Furthermore, we discuss current perspectives on the role of microbial indoles in human diseases such as diabetes, obesity, atherosclerosis, and cancers. Deciphering the function of indoles as biomarkers of metabolic state will facilitate the formulation of diet-based treatments and open unique therapeutic opportunities.

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微生物吲哚化合物在真核系统中的不同作用

吲哚及其衍生物广泛存在于不同的生命形式中，在原核生物中作为信号分子发挥作用，在真核生物中发挥更多样化的作用。在环境中发现的大多数吲哚归因于将色氨酸转化为吲哚及其衍生物的细菌酶。吲哚作为种间和种内信号在低等生物中的参与是众所周知的，许多报告表明，涉及微生物吲哚化合物的界际相互作用同样重要，因为它们影响防御系统甚至高等生物的行为。这篇综述总结了我们对不同真核生物中吲哚和吲哚衍生物功能特性的理解的最新进展。此外，我们讨论了目前关于微生物吲哚在人类疾病（如糖尿病、肥胖症、动脉粥样硬化和癌症）中作用的观点。破译吲哚作为代谢状态生物标志物的功能将有助于制定基于饮食的治疗方法并开辟独特的治疗机会。