Functional evaluation of a prebiotic-human milk oligosaccharide complex in alleviating necrotizing enterocolitis in neonatal rats

Neonatal necrotizing enterocolitis (NEC) remains a major cause of morbidity and mortality in newborns, highlighting the need for safe nutritional interventions. We evaluated a prebiotic complex containing GOS, FOS, and LAU in combination with the human milk oligosaccharides 2′-FL and LNnT in a neonatal rat model of NEC. Forty-eight pups were allocated to eight groups ( n = 6 per group). Mix2-L, Mix2-H, and Mix2N-H increased baseline-adjusted body weight on D7–D9 relative to the model group, and the interventions improved colon morphology, histopathology, inflammatory and barrier-related measures, goblet-cell features, and mucin composition, with Mix2N-H showing the broadest response. Gut microbial community composition differed among groups (PERMANOVA pseudo-F = 3.819, R² = 0.455, P = 0.0001), and all eight cecal SCFAs showed significant overall group effects after FDR correction. In the 24 animals with exact microbiota–SCFA matching, Veillonella abundance was positively associated with butyrate (ρ = 0.663, q = 0.015) and propionate, whereas Ralstonia , Achromobacter , and Chryseobacterium showed negative associations with selected SCFAs. Mix2N-H also had higher butyrate than the model group. p-AKT/AKT and p-mTOR/mTOR differed among groups and were higher in several intervention groups than in the model group. These findings support a coordinated microbiota–SCFA–AKT/mTOR-associated response to prebiotic–HMO supplementation. These findings are based on a preclinical neonatal rat model.