Dietary flavonoid tectochrysin ameliorates dextran sodium sulfate-induced intestinal barrier dysfunction relevant to MAPK-NF-κB-MLCK signaling pathway

Intestinal barrier exerts a fundamental role in homeostasis and loss of barrier integrity is often implicated in diseases. In this study, we investigated the protective effect of tectochrysin (TEC), a flavonoid broadly existing in dietary plants, on the intestinal barrier dysfunction in DSS-induced colitis mice. TEC treatment significantly improved DSS-induced clinical performances and intestinal pathological alterations including high scores of disease activity index (DAI), shortened colon length, apoptosis of intestinal epithelial cells and loss of tight junction (TJ) molecules. As for the mechanism, TEC suppressed pro-inflammatory cytokines (TNF-α, IFN-γ), alleviated macrophage infiltration, and shifted macrophage polarization from the pro-inflammatory M1 phenotype to the anti-inflammatory M2 phenotype. Furthermore, TEC targeted DSS-induced MAPK-NF-κB-MLCK signal cascade in inflamed intestine. Consequently, our findings suggested that administration of dietary flavonoid TEC effectively ameliorated DSS-induced intestinal barrier damage and offered a potential therapeutic strategy for intestinal barrier dysfunction.