The human gut microbiota is a functioning endocrine organ and stands at the intersection between dietary components and health or disease. There are very many microbial metabolites with numerous structures and functions arising from the gut microbial fermentation of foods and become signals for biological communication in the human body. These small molecules can be absorbed and delivered to distant organs through the circulatory system to build the gut–systemic axis. The gut microbial metabolomes are thus believed to play important roles in regulating cardiometabolic health and provide opportunities in mechanistic research and new drug discovery. Measurement of these novel microbial metabolites in clinical samples may serve as a tool for investigating disease biomarkers. In the past decade, the development of untargeted and targeted metabolomics approaches using NMR, LC/MS, and GC/MS has contributed to the exploration of gut microbial metabolomes in cardiometabolic health and disease. Some important targets are currently being translated into clinical applications. In this review article, we introduce an oral carnitine challenge test developed as an example to demonstrate the potential applications in personalized nutrition based on the function of gut microbiota. It is a method taking the gut microbiota as a bioreactor and provides fermentable materials as inputs and measures the outputs of targeted microbial byproducts in the blood or urine. This challenge test may be extended to measure metabolites from microbial fermentation related to other endocrinological or inflammatory diseases. We review current gut metabolome research approaches and propose a gut microbial functional measurement using a challenge test. We suggest that the maturation in measuring gut microbial metabolites may provide an important piece to complete the puzzle of precision medicine.

中文翻译：

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肠道微生物代谢物在心脏代谢健康中的测定和转化研究

人体肠道菌群是功能正常的内分泌器官，位于饮食成分与健康或疾病之间的交汇处。食物的肠道微生物发酵会产生许多具有许多结构和功能的微生物代谢产物，并成为人体生物通讯的信号。这些小分子可以被吸收并通过循环系统传递到远处的器官，以建立肠道-全身轴。因此，认为肠道微生物代谢组在调节心脏代谢健康中起重要作用，并为机理研究和新药发现提供了机会。对临床样品中这些新型微生物代谢产物的测量可作为研究疾病生物标志物的工具。在过去的十年中 使用NMR，LC / MS和GC / MS进行无针对性和有针对性的代谢组学方法的发展，已为探索心脏代谢健康和疾病中的肠道微生物代谢组做出了贡献。一些重要的目标目前正在转化为临床应用。在这篇综述文章中，我们介绍了一个口服肉碱挑战试验，该试验以举例说明肠道菌群功能在个性化营养中的潜在应用。它是一种以肠道菌群为生物反应器，并提供可发酵物质作为输入，并测量血液或尿液中目标微生物副产物输出的方法。这项挑战测试可能会扩展到测量与其他内分泌或炎症性疾病相关的微生物发酵代谢产物。我们回顾了当前的肠道代谢组学研究方法，并提出了使用挑战性测试的肠道微生物功能测量方法。我们建议测量肠道微生物代谢产物的成熟度可能为完成精密医学难题提供重要的手段。