Tea polyphenols alleviate intestinal barrier injury, regulate ERK/NF-κB pathway, and restore gut microbiota in perfluorooctanoic acid-exposed mice.

Perfluorooctanoic acid (PFOA), a persistent environmental contaminant, has been found to induce intestinal damage. Dietary tea polyphenols (TPs) have been reported to alleviate gastrointestinal diseases, however, the underlying mechanism through which TPs alleviate PFOA-induced ileal barrier injury remains unclear. Here, the effects of TPs on oxidative stress, intestinal permeability, extracellular signal-regulated kinase (ERK) / nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) signaling pathway, and gut microbiota in mice were evaluated. The results showed that TPs alleviated oxidative stress by elevating the serum GSH and CAT activities, and reducing MDA levels. Moreover, TPs decreased intestinal permeability by reducing serum DAO and LPS levels, upregulating the expression of claudin-1 and occludin, and inhibiting the phosphorylation of ERK and NF-κB in the ileum. Additionally, 16S rRNA gene sequence analysis revealed that TPs reversed PFOA-induced gut dysbiosis by decreasing harmful bacteria of Desulfovibrio and Ileibacterium, and increasing beneficial bacteria of Lachnospiraceae_NK4A136_group and Ligilactobacillus. This study reveals positive effects of TPs as a potential dietary intervention against pollutant-induced enterotoxicity.