Enteral Nutrition Is Associated with a Distinct Gut Microbiome Composition and Fermentation Capacity Profile After Acute Colonic Injury in Rats.

Abstract

Enteral nutrition (EN) is known to promote mucosal healing in inflammatory bowel disease, and multi-omics data suggest that the gut microbiome mediates its therapeutic effects. However, the impact of EN and its components on the gut community during recovery from acute epithelial injury remains incompletely understood. We used whole-genome metagenomic sequencing to investigate the effect of an EN formula based on extruded amaranth flour and pea protein on the gut microbiome in a dextran sulfate sodium (DSS) rat model of acute colonic injury. Three groups were compared, as follows: an unchallenged control (n = 9) with standard chow, a colonic injury (5% DSS; n = 9) group with standard chow, and a colonic injury (5% DSS; n = 9) group with EN. Injury was confirmed histologically (median MCHI score was 2, indicating epithelial damage without inflammation). DSS caused significant weight loss. Animals receiving EN regained baseline weight faster, by day 14, whereas animals on standard chow achieved recovery only by day 21. Differences in energy intake should be further investigated to validate the effect of EN on body weight recovery. At day 21, both injury groups demonstrated higher relative abundances of Bacteroidaceae and Erysipelotrichaceae, including the mucin-degrader Allobaculum mucilyticum, compared with the control group. Conversely, Lactobacillus abundance, notably Lactobacillus acidophilus, was higher in the EN group than in both other groups, as was the inferred capacity for lactate-producing fermentation. These findings suggest that EN is associated with a distinct microbial composition and inferred metabolic profile during the post-injury period, with lactobacilli as one of the potential mediators of its effects.