Lactobacillus plantarum BC299 can alleviate dextran sulphate sodium-induced colitis by regulating immune response and modulating gut microbiota

It is well known that probiotics are effective in relieving inflammatory bowel disease (IBD). However, their exact mechanism is still unclear. Herein, we evaluated the effect of novel Lactobacillus plantarum BC299 on dextran sodium sulphate (DSS)-induced colitis model mice and investigated the molecular mechanism. We found BC299 could regulate immune response and reduce immunosuppression by enhancing the expression of Th1 T cells in cyclophosphamide-induced immunosuppressive model mice. Meanwhile, DSS-induced colitis model mice were furtherly constructed. The results displayed BC299 can restore bodyweight and relieve colon morphology of colitis mice. Real-time quantitative polymerase chain reaction results demonstrated BC299 can regulate immune response by reducing the expression of TNF-alpha and IL-1 beta mRNA and increasing the expression of IL-10 and TGF-beta mRNA. Moreover, BC299 administration reshaped and increased the diversity of gut microbiota in IBD mice. Therefore, BC299 can alleviate colitis by regulating immune response and modulating gut microbiota.