Anti-colitis effect of Lactobacillus sakei K040706 via suppression of inflammatory responses in the dextran sulfate sodium-induced colitis mice model

•K040706 attenuated DSS-induced colitis severity and epithelial injury.•K040706 suppressed the DSS-induced expression of pro-inflammatory mediators.•K040706 downregulated the DSS-induced activation of TLR4/NF-κB/STAT3 signaling.•K040706 improved the intestinal microbiota composition.•K040706 has potential as a treatment option for inflammatory bowel disease. Lactobacillus strains are used in the functional food industry as promising probiotics with purported beneficial effects. We recently reported on the immunostimulatory effects of Lactobacillus sakei K040706 (K040706) in macrophages and in a cyclophosphamide-induced immunosuppression model. And this study assessed the anti-inflammatory effects and molecular mechanisms involving K040706 in a mouse model of colitis with dextran sodium sulfate (DSS). K040706 significantly attenuated the clinical signs and histological characteristics in DSS-induced colitic mice, which are well-correlated with the restoration of tight junction protein expression and the significant reduction of immune cell infiltration and expression of ICAM-1 and VCAM-1. Moreover, K040706 reduced the abnormal expression of pro-inflammatory mediators, such as iNOS, TNF-α, IL-1β, and IL-6, and the activation of NF-κB, STAT3 and TLR4. K040706 also improved the composition of intestinal microbiota. These results suggest K040706 has shown significant anti-inflammatory effects in a DSS-induced colitis model and has the potential to treat IBD.