Lactobacillus casei DG and its postbiotic reduce the inflammatory mucosal response: an ex-vivo organ culture model of post-infectious irritable bowel syndrome

BMC Gastroenterol. 2017 Apr 14;17(1):53. doi: 10.1186/s12876-017-0605-x.


Background: The evidence on the role of gut microbiota in post-infectious irritable bowel syndrome (PI-IBS) is convincing. Lactobacillus spp. positively affect IBS symptoms, although the mechanisms through which probiotics exert their beneficial effects are largely unknown. The aim of the study is to evaluate the role of Lactobacillus casei DG (LC-DG) and its postbiotic (PB) in modulating the inflammatory/immune-response in PI-IBS in an ex-vivo organ culture model.

Methods: Ex vivo cultures of ileal and colonic mucosa from 10 PI-IBS, diarrhea predominant subtype (D) patients, and 10 healthy controls (HC) were treated with LPS, LC-DG and PB. Interleukin (IL)-1α, IL-6, IL-8 and IL-10 mRNA levels were assessed by real-time PCR and Toll like receptor 4 (TLR-4) protein expression by Western blotting.

Results: At baseline, IL-1α, IL-6 and IL-8 mRNA levels as well as TLR-4 protein expression were significantly higher while IL-10 mRNA levels were lower in PI-IBS D than in HC in both ileum and colon. LC-DG and PB significantly reduced the mRNA levels of pro-inflammatory cytokines and TLR-4 while increased that of IL-10 after LPS stimulation. The protective effect was more pronounced for PB than LC-DG treatment.

Conclusion: LC-DG and its PB attenuate the inflammatory mucosal response in an ex-vivo organ culture model of PI-IBS D.

Keywords: Post-infectious irritable bowel syndrome; Postbiotic; Probiotics.

MeSH terms

  • Blotting, Western
  • Case-Control Studies
  • Colon
  • Female
  • Gastrointestinal Microbiome / immunology
  • Humans
  • Ileum
  • In Vitro Techniques
  • Inflammation
  • Interleukin-10 / genetics
  • Interleukin-10 / immunology
  • Interleukin-1alpha / genetics
  • Interleukin-1alpha / immunology
  • Interleukin-6 / genetics
  • Interleukin-6 / immunology
  • Interleukin-8 / drug effects
  • Interleukin-8 / genetics
  • Interleukin-8 / immunology
  • Intestinal Mucosa / drug effects*
  • Intestinal Mucosa / immunology
  • Intestinal Mucosa / microbiology
  • Irritable Bowel Syndrome / immunology
  • Irritable Bowel Syndrome / microbiology*
  • Lacticaseibacillus casei*
  • Lipopolysaccharides / pharmacology*
  • Male
  • Middle Aged
  • Organ Culture Techniques
  • Probiotics / pharmacology*
  • RNA, Messenger / drug effects*
  • RNA, Messenger / metabolism
  • Real-Time Polymerase Chain Reaction
  • Toll-Like Receptor 4 / drug effects
  • Toll-Like Receptor 4 / metabolism


  • CXCL8 protein, human
  • IL10 protein, human
  • IL1A protein, human
  • IL6 protein, human
  • Interleukin-1alpha
  • Interleukin-6
  • Interleukin-8
  • Lipopolysaccharides
  • RNA, Messenger
  • TLR4 protein, human
  • Toll-Like Receptor 4
  • Interleukin-10