Prebiotics of Lactobacillus plantarum mitigate inflammation but compromise immunity

Inflammation serves as a crucial feedback mechanism in response to external stimuli, with severe inflammatory reactions leading to significant damage in the body. Evidence indicates that Lactobacillus plantarum can suppress inflammatory responses, effectively maintaining intestinal balance and stability, and are widely used in pig farming. Prebiotics, when compared to live bacteria, demonstrate a more pronounced probiotic function. In this study, lipopolysaccharides (LPS) was utilized as a stimulus for an inflammation model. Through in vitro cell experiments and in vivo pig trials, it was observed that oral administration of Lactobacillus plantarum prebiotics effectively inhibited inflammation. Moreover, the anti-inflammatory effect was improved with higher doses of prebiotics, without any observed intestinal damage. Additionally, flow cytometry analysis of peripheral blood mononuclear cells (PBMCs) and Peyer's patches (PPs) revealed alterations in various immune cell populations, including T cells, B cells, dendritic cells (DCs), and natural killer (NK) cells. Overall, the results showed an increase in T cell proportion during inflammation and a decrease upon resolution. B cells and DCs were suppressed during both inflammation and recovery periods. NK cells were unaffected by inflammation but their proportion decreased during the recovery phase. This study, for the first time, highlights that while Lactobacillus plantarum prebiotics alleviate clinical symptoms of inflammation, immune responses involving B cells and DCs are also suppressed, in addition to T cell immune responses. This finding not only enhances our understanding of the mechanisms of action of Lactobacillus plantarum prebiotics but also provides fundamental data for future therapeutic interventions and immunological applications.