Lacto- N -biose Improves Acute Colitis in Mice by Modulating Gut Microbiota and Metabolites

Lacto-N-biose (LNB) as the core structure among human milk oligosaccharides remained insufficiently characterized in terms of the potential to ameliorate colitis. This study investigated effects of LNB in colitis by using dextran sulfate sodium salt to induce mouse model. Results demonstrated that LNB significantly ameliorated the increase in disease activity index, suppressed immune factors TNF-α, F4/80, IL-6, and IFN-γ, increased factors IL-4 of colitis mice, and the high-dose group exhibited better efficacy. LNB also protected colonic architecture and repairing the intestinal mucosal barrier by facilitating the expression of Muc2, ZO-1, Occludin, and Claudin1. Furthermore, LNB restored gut microbial flora balance by promoting levels of Akkermansia and Lachnospiraceae bacterium UBA3282 while decreasing Prevotella and Cryptobacteroides. In fecal metabolomics, LNB downregulated the relative content of 7α-hydroxycholesterol, suggesting that its improvement of colitis may involve bile secretion and primary bile acid biosynthesis pathways. These findings provide new insights for the development and comprehensive utilization of LNB.