Dietary modulation of intestinal microbes prolongs survival in a Hirschsprung disease mouse model.

BACKGROUND & AIMS: Enterocolitis is a common, potentially deadly complication of Hirschsprung disease (HSCR), a congenital anomaly defined by absence of enteric neurons from distal bowel. Unexpectedly, we discovered diet dramatically affects lifespan of a HSCR mouse model (Piebald lethal, sl/sl). METHODS: We analyzed diet-dependent sl/sl survival, diet and stool composition by untargeted metabolomics, gut microbiome by 16S rDNA sequencing and culture on MacConkey agar, colon epithelial anatomy by light and electron microscopy, colon epithelial gene expression by bulk RNA sequencing, colon epithelial oxygen level by pimonidazole staining, intestinal permeability to 4kDa FITC-dextran, and the impact on sl/sl survival of antibiotic or tungstate treatment to broadly or selectively eliminate gut microbes. RESULTS: Detrimental diet-fed sl/sl mice had elevated colon epithelial oxygen, abnormal distal colon epithelial mitochondria, reduced distal colon epithelial mRNA encoding oxidative phosphorylation proteins, and increased Enterobacteriaceae. Protective diet promoted colon epithelial hypoxia, supported distal colon epithelial mitochondrial metabolism, elevated proximal colon anti-microbial peptides, improved epithelial barrier function, reduced Enterobacteriaceae, and tripled median sl/sl lifespan. Protective diet-fed sl/sl mice had higher fecal butyrate and other metabolites that may underlie these effects. Tungstate-mediated inhibition of Enterobacteriaceae anaerobic respiration also improved sl/sl survival. CONCLUSIONS: These observations suggest for the first time to our knowledge that dietary interventions (other than breastfeeding) might prevent Hirschsprung disease-associated enterocolitis.