Anti-infectious properties of the probiotic Saccharomyces cerevisiae CNCM I-3856 on enterotoxigenic E. coli (ETEC) strain H10407

Abstract

Enterotoxigenic Escherichia coli (ETEC) are major food-borne pathogens responsible for traveler's diarrhea. The production of adhesins and the secretion of enterotoxins constitute the major virulence traits of the bacteria. Treatments are mainly symptomatic and can involve antibiotherapy. However, given the rise of antibiotic resistance worldwide, there is an urgent need for the development of new preventive strategies for the control of ETEC infections. Among them, a promising approach is the use of probiotics. The aim of this study was to investigate, using complementary in vitro and in vivo approaches, the inhibitory potential of the yeast Saccharomyces cerevisiae CNCM I-3856 against the human ETEC reference strain H10407. In conventional culture media, S. cerevisiae significantly reduced ETEC growth and toxin production. The yeast also inhibited bacterial adhesion to mucin-agar and intestinal Caco-2/TC7 cells in a dose-dependent manner. Lastly, pre-treatment with S. cerevisiae inhibited interleukin-8 production by ETEC-infected intestinal cells. In streptomycin-treated mice, the probiotic yeast decreased bacterial colonization, mainly in the ileum, the main site of ETEC pathogenesis. For the first time, this study shows that the probiotic yeast S. cerevisiae CNCM I-3856 can exert an anti-infectious activity against a human ETEC strain through a multi-targeted approach, including inhibition of bacterial growth and toxin production, reduction of bacterial adhesion to mucins and intestinal epithelial cells, and suppression of ETEC-induced inflammation. Interestingly, the highest activity was obtained with a prophylactic treatment. Further studies will aim to assess the effect of the yeast on ETEC survival and virulence under human simulated digestive conditions.

Spatial and temporal modulation of enterotoxigenic E. coli H10407 pathogenesis and interplay with microbiota in human gut models

“…The mucus layer forms a natural habitat of intestinal symbionts and can serve as a nutrient-rich environment facilitating growth of both endosymbionts as pathogens. These observations complement our previous study where ETEC was also found to attach to mucin proteins yet in absence of microbiota [22]. While the nutritional role of the mucus layer for ETEC is unknown, it is noteworthy that ETEC's mucosal adhesion efficacy was higher (51%) than that of the adherent invasive E. coli (AIEC) pathotype (20%) [23].…”

Investigation into In Vitro and In Vivo Caenorhabditis elegans Models to Select Cheese Yeasts as Probiotic Candidates for their Preventive Effects against Salmonella Typhimurium

“…These results showed the inhibitory activity of the yeasts against the ST and were in accordance with Lima et al [ 55 ], who demonstrated that S. cerevisiae strains from Brazilian kefir-fermented milk presented an antagonistic activity against Gram-negative bacteria. Similar results were obtained by Roussel et al [ 56 ] with a S. cerevisiae strain on an enterotoxigenic E. coli . On the contrary, Binetti et al [ 57 ] showed that yeasts from autochthonal cheese starters did not inhibit the growth of Salmonella Enteritidis, E. coli, or Staphylococcus aureus .…”

Lactobacillus rhamnosus GG and Saccharomyces cerevisiae boulardii exert synergistic antipathogenic activity in vitro against enterotoxigenic Escherichia coli

“…Also, Buts et al (2006) reported that S. boulardii produces a protein phosphatase that inhibited E. coli endotoxins in the small intestine of rats. Furthermore, Roussel et al (2018) demonstrated that the probiotic yeast Saccharomyces cerevisiae CNCM I-3856 reduces ETEC toxin concentrations in culture media through active removal of the toxin by the yeast strain. The increased https://www.wageningenacademic.com/doi/pdf/10.3920/BM2019.0064 -Friday, February 21, 2020 3:02:14 AM -Universiteit Gent IP Address:157.193.240.3 ammonium and branched SCFA concentrations observed during the incubations with S. boulardii confirms the stimulation of proteolytic activity.…”