Background: Leaky gut and microbiota dysbiosis have been linked to many chronic inflammatory diseases. Strengthening the gut epithelial barrier is a novel but overlooked strategy for management of gut microbiota-associated illnesses.
Results: Using the dextran sulfate sodium (DSS)-induced gut barrier injury-based colitis model, we found that DSS-induced weight loss, rectal bleeding, and colonic epithelium damage were ameliorated in dual-specificity phosphatase 6 (Dusp6)-deficient mice. These protective effects could be attributed to the enhanced colon barrier integrity conferred by Dusp6-deficiency. Consistently, DUSP6 mutation in Caco-2 cells elevated transepithelial electrical resistance, enhanced tight-junctions, and increased expression of microvilli-associated genes. DUSP6-deficient Caco-2 cells also showed increased mitochondrial oxygen consumption accompanied by altered glucose metabolism and decreased glycolysis. Remarkably, our microbiome analysis found that Dusp6-deficient mice harbored fewer pathobionts and facultative anaerobes and more obligate anaerobes than wild-type mice after DSS treatment. Our cohousing and fecal microbiota transplantation experiments demonstrated that the gut/fecal microbiota derived from Dusp6-deficient mice also conferred protection against colitis.
Conclusion: We have thus identified Dusp6 deficiency as beneficial in enhancing gut barrier integrity, elevating epithelial phosphoxidation, and maintaining the gut microbiota eubiosis necessary to protect against colitis.