Probiotics: progress toward novel therapies for intestinal diseases

Abstract
Purpose of review As the beneficial effects of probiotics on health and disease prevention and treatment have been well recognized, the demand for probiotics in clinical applications and as functional foods has significantly increased in spite of limited understanding of the mechanisms. This review focuses on the most recent advances in probiotic research from genetics to biological consequences regulated by probiotics and probiotic-derived factors. Recent findings Genomic and proteomic studies reveal genes and proteins involved in probiotic adaptation in the host and while exerting their beneficial effects. Recent studies in cell culture and in animal models emphasize probiotic functions in intestinal development, nutrition, host microbial balance, cytoprotection, barrier function, innate immunity, and inflammation. Most importantly, several novel and known probiotic-derived factors have been characterized, which regulate host-signaling pathways and mediate probiotic function. Summary Progress in understanding probiotic mechanisms of action will increase our basic understanding of biological crosstalk and provide the rationale to support the development of new hypothesis-driven studies to define the clinical efficacy of probiotics for intestinal disorders.