Lactobacillus plantarum C29 alleviates NF-κB activation and Th17/Treg imbalance in mice with TNBS-induced colitis

In this study, we examined whether Lactobacillus plantarum C29 could restore 2,4,6-trinitrobenzenesulfonic acid (TNBS)-induced T helper 17 (Th17)/regulatory T cells (Tregs) imbalance in mice. Treatment with C29 inhibited the differentiation of splenic T cells into Th17 cells and the expression of retinoic acid receptor-related orphan receptor gamma t (RORγt) and IL-17 in vitro, whereas promoting the differentiation into Tregs. Oral administration of Lactobacillus plantarum C29 in mice attenuated TNBS-induced colon shortening, myeloperoxidase (MPO) activity, inducible Nitric oxide (NO) synthase, and cyclooxygenase-2 expression, and activation of NF-κB in the colon of mice. C29 treatment downregulated TNF-α, IL-17, and IL-1β expression, while increasing IL-10 expression. C29 treatment suppressed TNBS-induced Th17 cell differentiation and reduced IL-17 and RORγt expression, while promoting the TNBS-suppressed Tregs differentiation and IL-10 and forkhead box P3 expression. These findings suggest that C29 can alleviate colitis by modulating NF-κB activation as well as Th17/Treg balance.