Lactobacillus plantarum A3 attenuates ulcerative colitis by modulating gut microbiota and metabolism

Antibiotics are widely used to treat various diseases. However, growing evidence indicates that antibiotic therapy in human life increases the incidence of inflammatory bowel disease (IBD). Therefore, we need appropriate methods to reduce the incidence or symptoms of IBD. In this study, we used lincomycin hydrochloride to construct a gut microbial dysbiosis model in mice, and then, constructed an ulcerative colitis (UC) model. Meanwhile, we used Lactobacillus plantarum A3 from equine to treat UC in mice with gut microbial dysbiosis. The results showed that lincomycin hydrochloride had little effect on the small gut microbiota in mice, but had a more destructive effect on the large intestin. Lactobacillus plantarum A3 alleviated the symptoms of UC in mice, which was reflected in its significantly reduced spleen index and disease activity index (DAI) (p < 0.05), inhibited the shortening of colon and alleviated the invasion of inflammatory cells in the colon. Moreover, we found that it played a mitigatory role by inhibiting oxidative stress and regulating inflammatory cytokines in mice. At the same time, it restored the diversity and composition of the colonic microbiota and significantly increased the abundance of beneficial bacteria such as Blautia and Akkermansia (p < 0.05); Notably, it significantly increased the concentrations of arachidonoyl ethanolamide phosphate (AEA-P) and cortisone (p < 0.05) which have analgesic and anti-inflammatory effects. In conclusion, our study found that Lactobacillus plantarum A3 has the potential to regulate UC in mice with gut microbial dysbiosis.