Mechanisms of Action of Probiotics

Ko, Jae Sung

Abstract

There is scientific evidence that administration of probiotics is effective in the treatment of acute infectious diarrhea in children and the prevention of antibiotic associated diarrhea and nosocomial/ community acquired diarrhea. Probiotics prevent relapse of recurrent pouchitis and decrease the initial onset of pouchitis in ulcerative colitis. Probiotic organisms suppress growth of pathogens as well as their epithelial attachment and/or invasion either directly by secreting antimicrobial substances or by stimulating host expression of protective molecules. Additionally, probiotics enhance mucosal barrier function and can stimulate host production of immunosuppressive molecules that downregulate inflammatory responses or allergic immune response. Mechanisms of action explain therapeutic effects and randomized controlled trials are warranted before recommendations for therapeutic or preventive use can be given.