Institute of Nutritional Science, University of Giessen, Giessen, Germany.
Mol Nutr Food Res. 2015 Feb;59(2):355-64. doi: 10.1002/mnfr.201400160. Epub 2014 Nov 27.
Various biological effects have been postulated for human milk oligosaccharides (HMO), as deduced from in vitro, animal, and epidemiological studies. Little is known about their metabolic fate in vivo in the breast-fed infant, which is presented here.
Human milk and infant urine and feces were collected from ten mother-child pairs and analyzed by MALDI-TOF MS (/MS), accompanied by high-performance anion-exchange chromatography with pulsed amperometric detection. Previously, we detected intact small and complex HMO in infant urine, which had been absorbed from gut, as verified via intrinsic (13) C-labeling. Our current work reveals the presence of novel HMO metabolites in urine and feces of breast-fed infants. The novel metabolites were identified as acetylated HMOs and other HMO-like structures, produced by the infants or by their gut microbiota. The finding of secretor- or Lewis-specific HMO in the feces/urine of infants fed with nonsecretor or Lewis-negative milk suggested a correspondent modification in the infant.
Our study reveals new insights into the metabolism of neutral HMO in exclusively breast-fed infants and provides further indications for multiple factors influencing HMO metabolism and functions that should be considered in future in vivo investigations.
从体外、动物和流行病学研究中推断，人乳寡糖（HMO）具有各种生物学效应。关于其在母乳喂养婴儿体内的代谢命运知之甚少，本文对此进行了介绍。
从 10 对母婴对中收集母乳、婴儿尿液和粪便，并通过 MALDI-TOF MS（/MS）进行分析，同时进行高效阴离子交换色谱-脉冲安培检测。此前，我们通过内源性（13）C 标记验证了从肠道吸收的婴儿尿液中存在完整的小而复杂的 HMO。我们目前的工作揭示了母乳喂养婴儿尿液和粪便中存在新型 HMO 代谢物。新型代谢物被鉴定为乙酰化 HMO 和其他 HMO 样结构，由婴儿或其肠道微生物群产生。在喂食非分泌型或 Lewis 阴性母乳的婴儿的粪便/尿液中发现分泌型或 Lewis 特异性 HMO，提示婴儿发生相应的修饰。
本研究揭示了母乳喂养婴儿中性 HMO 代谢的新见解，并为影响 HMO 代谢和功能的多种因素提供了更多证据，这些因素在未来的体内研究中应加以考虑。
