Lactobacillus reuteri alleviate the severity of chemicallyinduced colitis in mice

Abstract

Inflammatory bowel diseases (IBDs) are associated with reduced diversity and decreased contribution of probiotic bacteria within the comensal microbiota. A range of probiotic bacteria, including the genera Lactobacillus, could be protective in IBDs due to their capacity to trigger anti-inflammatory mechanisms 1. The aim of the study was to explore immunomodulatory impact of probiotic bacteria. Lactobacillus reuteri (LR) and its contribution to the alleviation of severity of a 2,4,6-trinitrobenzene sulfonic acid (TNBS)- induced colitis in mice. Colitis was induced in outbred Intor Swiss:Albino mice by a single administration of TNBS dissolved in 50% ethanol (day 0). LR in phosphate buffer solution (5x106 CFU/mL, p.o.) was given daily, 7 days prior and/or 7 days after day 0 (n=10 per treatment). Mice subjected to the induction of colitis without LR treatment were referent. A significant reduction in disease severity was noticed only in group treated by LR prior and upon colitis induction. The alleviation of disease severity correlated with lessening of local infiltration of leukocytes, a decrease in local inflammatory response (myeloperoxidase activity, production of superoxide ions, IL-6, a nd T NFα), a nd a n increase in local production of IL-10. Presented results show that LR triggers a regulatory mechanism which alleviates severity of TNBS-induced colitis in mice, implying that it is worth further evaluation in prevention and treatment of IBDs.