LAUSR

OBJECTIVE This study explores the effects of fecal microbiota from children with vitamin A (VA) deficiency on colonic mucosal barrier function. METHODS The composition of gut microbes was identified in children with different VA levels, then feces from children with normal VA or VA deficiency was collected separately and transplanted into germ-free (GF) mice, respectively. Three weeks after transplantation, the colon morphology, colonic tight junction proteins, gut microbes, and metabolites were evaluated. RESULTS In children, Bifidobacterium and Bacteroides were positively correlated with VA levels. Colonization of VA deficiency fecal microbiota markedly impaired colonic development in GF mice, down-regulated colonic tight junction-related proteins occludin and claudin-1, and reduced immunoglobulin A secretion. Furthermore, fecal microbiota transplantation with different VA levels altered composition of gut microbes and bile acid metabolism pathways in GF mice. CONCLUSION These data suggest that fecal microbiota from children with VA deficiency attenuates colonic barrier function in GF mice, which may be achieved by changing the bile acid metabolic pathways.