A disturbance in microbial balance of the gastrointestinal tract is often associated with diarrhea. Therefore, probiotics, as beneficial microorganisms for host health, have attracted clinical attention for their potential therapeutic application in the treatment of diarrhea. This review focuses on new research findings relevant to the effects of probiotics on diarrhea prevention and treatment and potential mechanisms of action for this alternative therapy for diarrhea.
Clinical trials suggest potential beneficial effects of probiotic therapy for preventing and treating antibiotic-associated diarrhea, acute diarrhea including rotavirus-induced diarrhea, traveler's diarrhea, and diarrhea-predominant irritable bowel syndrome. The most extensively studied probiotics for diarrhea are Lactobacillus, Bifidobacterium and Saccharomyces, with potential mechanisms of therapeutic action based on the protection of intestinal epithelial cell and barrier function, prevention of enterotoxin binding to intestinal epithelial cells, and regulation of intestinal microbial environment.
Growing evidence suggests that probiotics may serve as a functional food in the treatment of diarrhea. Remaining challenges include identifying mechanisms of action to provide the basis of more refined hypothesis-driven clinical trials. The correct combination and concentration of probiotics applied to the appropriate gastrointestinal disorders may improve the efficacy of this approach for diarrhea and other diseases.
aDepartment of Pediatrics, Division of Gastroenterology, Hepatology and Nutrition
bDepartment of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
Correspondence to D. Brent Polk, MD, 2215 Garland Avenue, Building MRB IV, Room 1025, Nashville, TN 37232-0696, USA Tel: +1 615 322 7449; fax: +1 615 343 5232; e-mail: firstname.lastname@example.org
The work in the authors' laboratory is supported by NIH grants DK 065744 (FY), DK066176, DK56008, and DK54993 (DBP) and DK58404 (Vanderbilt University Digestive Disease Research Center).