Lactobacillus reuteri-mediated dietary xylooligosaccharides enhance jejunal cell survival via suppression of oxygen-dependent apoptotic processes in a pig model

Xylooligosaccharides (XOS), classified as non-digestible functional oligosaccharide, are conventionally regarded as passersbyin the small gut. However, this study has reframed the conventional paradigm by demonstrating that XOS interact with microbiota to regulate the survival of small intestinal epithelial cells. First, we found that XOS improved growth performance of piglets by enhancing nutrition utilization and promoting villus elongation in the small gut, concomitant with better intestinal morphology and barrier function. Then, our results demonstrated that the expression of jejunal nutrient transporters was significantly upregulated, correlating with enhanced nutrient utilization; the jejunal villus elongation was attributed to XOS-mediated inhibition of epithelial apoptosis rather than proliferation promotion, thereby prolonging epithelial cell survival. Next, the microbiome data revealed that XOS optimized microbiota composition of jejunal mucosa, and elevated L. reuteri abundance; while proteomics results demonstrated that XOS modulated epithelial energy metabolism by suppressing oxygen-dependent oxidative phosphorylation pathways.