Probiotic microorganisms may benefit the host by influencing diverse physiological processes, whose nature and underlying mechanisms are still largely unexplored. Animal models are a unique tool to understand the complexity of the interactions between probiotic microorganisms, the intestinal microbiota, and the host. In this regard, in this pilot study, we compared the effects of 5-day administration of three different probiotic bacterial strains (Bifidobacterium bifidum MIMBb23sg, Lactobacillus helveticus MIMLh5, and Lacticaseibacillus paracasei DG) on three distinct murine intestinal sites (ileum, cecum, and colon). All probiotics preferentially colonized the cecum and colon. In addition, probiotics reduced in the ileum and increased in the cecum and colon the relative abundance of numerous bacterial taxonomic units. MIMBb23sg and DG increased the inducible nitric oxide synthase (iNOS) in the ileum, which is involved in epithelial homeostasis. In addition, MIMBb23sg upregulated cytokine IL-10 in the ileum and downregulated the cyclooxygenase COX-2 in the colon, suggesting an anti-inflammatory/regulatory activity. MIMBb23sg significantly affected the expression of the main gene involved in serotonin synthesis (TPH1) and the gene coding for the serotonin reuptake protein (SERT) in the ileum and colon, suggesting a potential propulsive effect toward the distal part of the gut, whereas the impact of MIMLh5 and DG on serotonergic genes suggested an effect toward motility control. The three probiotics decreased the expression of the permeability marker zonulin in gut distal sites. This preliminary in vivo study demonstrated the safety of the tested probiotic strains and their common ability to modulate the intestinal microbiota. The probiotics affected host gene expression in a strain-specific manner. Notably, the observed effects in the gut were site dependent. This study provides a rationale for investigating the effects of probiotics on the serotonergic system, which is a topic still widely unexplored.
Valentina Taverniti, Valentina Cesari, Giorgio Gargari, Umberto Rossi, Cristina Biddau, Cristina Lecchi, Walter Fiore, Stefania Arioli, Ivan Toschi and Simone Guglielmetti
Part of the information contained in this website is exclusively addressed to healthcare professionals. Please confirm that you are a healthcare professional. Are you a healthcare professional?
This website contains links/references to third-party websites. By such links, SOFAR does not provide any guarantee nor gives its approval to their contents and quality. SOFAR does not have and does not accept any responsibility for the contents or the availability of such websites; SOFAR does not accept any liability for damage or injury resulting from the use of such contents, of whatever form. Users access such websites at their own risk. The information contained in this website is for information purposes only and not for diagnostic or therapeutic purposes. Thus, it does not substitute in any way medical and /or expert or other healthcare professionals or specialists ‘advice.