Effects of probiotics, drugs and metallic ions on diarrhea and their mechanisms

Infection disease induces two mechanisms, ion secretion which results from secretion of chloride from the basolateral to apical side of enterocyte and osmotic diarrhea which is the consequence of massive flux of water from the basolateral to the luminal side upon the osmotic gradient originating by non absorbed intestinal nutrients. In both osmotic or secretory diarrhea, the intestine reacts with homeostatic mechanisms to increase ion absorption. These mechanisms can be effectively exploited to counteract fluid loss. A model of intestinal infections using rotavirus (RV) in epithelial cells was set up and used to define a model of secretory and osmotic diarrhea in intestinal cell line in vitro. Using this model, antidiarrheal drugs were tested, namely zinc , Thiorphan and probiotics. Zinc in vitro decreased the ion secretion induced by RV-induced enterotoxic activity. Thiorphan showed a potent and selective inhibition of active secretion, being particularly effective in the first phase of RV diarrhea. The probiotics, Lactobacillus GG and Saccharomyces boulardii, are able to reduce RV induced Teer decrease and RV cytotoxic effect with different mechanism by inducing cell growth and differentiation. The use of drugs selectively active at the intestinal level, therefore, provide an effective options to treat intestinal infections in childhood.