Lactobacillus fermentum attenuates the proinflammatory effect of Yersinia enterocolitica on human epithelial cells

• Published in: Inflammatory bowel diseases 2007-01, Vol.13 (1), p.83-90
• Main Authors: Frick, Julia‐Stefanie, Schenk, Katrin, Quitadamo, Matteo, Kahl, Frauke, Köberle, Martin, Bohn, Erwin, Aepfelbacher, Martin, Autenrieth, Ingo B.
• Format: Article
• Language: English
• Subjects: Bacterial Adhesion; Cell culture; Cells, Cultured; Culture Media, Conditioned; Data processing; Endopeptidase K - pharmacology; Epithelial cells; Epithelial Cells - metabolism; Epithelial Cells - microbiology; Glycerophospholipids - chemistry; Glycerophospholipids - pharmacology; HeLa Cells; Humans; IL‐8; Infection; Inflammation; Inflammation Mediators - metabolism; Inflammatory bowel diseases; Inflammatory diseases; Interleukin 8; Interleukin-8 - secretion; Intestine; Iron Compounds - pharmacology; Lactobacilli; Lactobacillus; Lactobacillus fermentum; Lactobacillus fermentum - physiology; Molecular weight; NF- Kappa B protein; NF-kappa B - metabolism; p38 Mitogen-Activated Protein Kinases - metabolism; Phospholipase C; Phospholipids; probiotics; rac1 GTP-Binding Protein - metabolism; Yersinia; Yersinia enterocolitica; Yersinia enterocolitica - pathogenicity; Yersinia Infections - metabolism
• ISSN: 1078-0998; 1536-4844
• DOI: 10.1002/ibd.20009

Background: Lactobacilli represent a major component of the human microbiota. In this study we investigated whether and how Lactobacillus fermentum inhibits the proinflammatory responses of human epithelial cells on Yersinia enterocolitica infection. Methods: Human epithelial cells were exposed to Y. enterocolitica pYV− or L. fermentum or to both strains, combinations of heat‐killed L. fermentum or supernatant of L. fermentum cultures and Y. enterocolitica. The modulation of Y. enterocolitica induced IL‐8 levels in the culture supernatants was determined and activation of Rac, p38, and NF‐κB was investigated. Results: Exposure of human epithelial cells to L. fermentum does not induce NF‐κB activation and subsequent IL‐8 secretion in HeLa cells, whereas Y. enterocolitica induces NF‐κB activation and high levels of IL‐8. Viable L. fermentum, supernatant of L. fermentum cultures, but not heat‐killed L. fermentum, inhibited IL‐8 secretion of HeLa cells triggered by Y. enterocolitica. Lactobacillus fermentum‐exposed HeLa cells showed decreased Rac, p38, and NF‐κB activation after Y. enterocolitica infection. Treatment of L. fermentum supernatants with phospholipase C abolished the inhibitory effect, indicating that a secreted phospholipid mediates the antiinflammatory properties of L. fermentum. Adhesion to or invasion of Y. enterocolitica into epithelial cells was not altered by coincubation with L. fermentum. Conclusion: Our results lead to the conclusion that L. fermentum inhibits the Y. enterocolitica‐induced IL‐8 production by a possibly secreted phospholipid of