Gut mucosal and adipose tissues as health targets of the immunomodulatory mechanisms of probiotics

Immune balance and homeostasis at mucosal surfaces is a delicate process which could be modulated within the gut by introduced or resident probiotics. Consumption of probiotics is meant to augment the normal intestinal probiotic microbes in a commensal or symbiotic relationship via cellular and humoral immunomodulation, tissue-mediated resistance of pathogenic colonization, improvement of mucosal barrier integrity, and interaction with microbiota. To provide a critical perspective on the potential function of probiotics in gut associated immune disorders, this review gathers the latest literature of probiotics in immune-mediated chronic pathologies including inflammatory bowel disease, obesity, and diabetes, among others. Final thoughts on applications, safety, limitations and prospective research of probiotics as health-promoting agents over immune-mediated inflammatory diseases is approached. The interplay between probiotics, gut inflammation and metabolic events within the digestive system has revealed promising roles for probiotics in adipose tissue inflammation and gut microbiota modulation. In contrast to well-known effects on established cell/animal models, observations made on probiotics may not always be experienced in every human cohort. The interactions between the various probiotic mechanisms involved in human hosts have not been systematically characterized, except that hopes are highly placed at obtaining more robust data derived from controlled clinical trials along with the application of advanced “omics” needed to integrate multilayered data and elucidate these issues in the near future. •Description of probiotic immunomodulation at gut mucosa and adipose tissue levels.•The immunomodulatory mechanisms in hosts may target immune-mediated chronic disorders.•Probiotic prevention of inflammatory bowel disease, diabetes, obesity complications.•Limited evidence and variety of outcomes encourage design of controlled human trials.