Structure-function relationships of human milk oligosaccharides on the intestinal epithelial transcriptome in caco-2 cells and a murine model of necrotizing enterocolitis.

Scope. Necrotizing enterocolitis (NEC) is a devastating gastrointestinal emergency affecting preterm infants. Breastmilk protects against NEC, partly due to human milk oligosaccharides (HMOs). HMO compositions are highly diverse, and it is unclear if anti-NEC properties are specific to carbohydrate motifs. Here, this study compares intestinal epithelial transcriptomes of five synthetic HMOs (sHMOs) and examines structure-function relationships of HMOs on intestinal signaling. Methods and Results. This study interrogates the transcriptome of Caco-2Bbe1 cells in response to five synthetic HMOs (sHMOs) using RNA sequencing: 2′-fucosyllactose (2′-FL), 3-fucosyllactose (3FL), 6′-siallyllactose (6′-SL), lacto-N-tetraose (LNT), lacto-N-neotetraose (LNnT). Protection against intestinal barrier dysfunction and inflammation occurred in an HMO-dependent manner. Each sHMO exerts a unique set of host transcriptome changes and modulated unique signaling pathways. There is clustering between HMOs bearing similar side chains, with little overlap in gene regulation which is shared by all sHMOs. Interestingly, most sHMOs protect pups against NEC, exerting divergent mechanisms...