Table 1.
Deleterious actions of pathogens in the gut and beneficial effects of S. boulardii CNCM I-745
| Deleterious actions of pathogens | Beneficial effects of S. boulardii CNCM I-745 | |
|---|---|---|
| Escherichia coli | ||
| Barrier integrity | Epithelium disruption: • MLC phosphorylation and PKC activation lead to TJ disruption21 |
Epithelium restoration: • Inhibition of MLC phosphorylation4 • Restoration of barrier integrity through TJ protection |
| Diarrhea | • Alterations in electrolyte transport • Chloride secretion41,42 |
• Reduction of intestinal permeability • Reduction of chloride secretion and mannitol flow46 |
| Inflammation | • IL-8 secretion mediated by MAPK and NF-κB activation45 | • Reduced levels of secreted pro-inflammatory cytokines4 • Decrease in TNF-α level47 |
| Invasion | • Pathogenic strains of attaching and effacing bacteria40 | • Modulation of bacterial attachment to enterocytes by secreting alkaline phosphatase47 |
| Shigella | ||
| Barrier integrity | Epithelium disruption: • Modification of phosphorylation status of TJ proteins27 • TJ disruption due to reduction in claudin-1 expression27 • AJ disruption induced by E-cadherin intracellular domain cleavage48 |
Epithelium restoration: • Partial restoration of claudin-1 expression49 • Restoration of barrier integrity through TJ protection |
| Inflammation | • IL-8 secretion | • Inhibition of IL-8 secretion mediated by NF-κB and ERK1/2 phosphorylation49 |
| Salmonella | ||
| Barrier integrity | TJ disruption due to: • Decrease in ZO-1 expression28 • Modified phosphorylation status of occludin28 • Activation of RhoGTPase28 |
Epithelium restoration: • Reduction of RhoGTPase preserves TJ50,51 |
| Diarrhea | Decrease in TER28 | Restoration of barrier integrity through TJ protection |
| Invasion | • Salmonella typhimurium invasion led by translocation of effector proteins28 | • Deviated trajectory of Salmonella and modified motility in the gastrointestinal tract by trapping of Salmonella by S. boulardii53,54 • Increase in bacterial elimination in feces53,54 |
| Inflammation | • NF-κB and IL-8 secretion50,51 | • Up-regulation of anti-inflammatory cytokines (IL-10 and TGF-α)50,51 • Reduction in activation of MAPK and reduced level of inflammatory cytokines50,51 |
| Vibrio cholerae | ||
| Barrier integrity | Epithelium disruption: • Zonula occludens toxin55 • 84 kDa cholera enterotoxin55 |
Epithelium restoration: • Reduction of intestinal damage and mucosal lesions58 |
| Diarrhea | Hydroelectrolytic diarrhea due to: • cAMP stimulation55 • Chloride secretion55 • Cell adhesion leakage55 |
Antidiarrheic effects by: • 120 kDa protein secretion, which decreases cAMP56,57 • Decrease in chloride secretion56,57 |
| Rotavirus | ||
| Barrier integrity | Epithelium disruption: • Drastic reduction in TER38 • Alteration in TJ protein localization (ZO-1, occludin and claudin-1)38,59 |
Epithelium restoration: • Restoration of glutathione, which inhibits ROS production60 • Decrease in intestinal permeability60 |
| Diarrhea | • Noxious substance penetration40 • Alteration of redox balance enhanced by ROS production leads to chloride secretion60 |
• Inhibition of chloride secretion and reduction of diarrhea60 |
Abbreviations: AJ, adherens junction; cAMP, cyclic adenosine monophosphate; MAPK, mitogen-activated protein kinase; MLC, myosin light chain; NF-κB, nuclear factor-κB; PKC, protein kinase C; S. boulardii, Saccharomyces boulardii; TER, transepithelial resistance; TJ, tight junction; ZO-1, zonula occludens-1.