Inhibitory effects of Lactobacillus casei subsp. rhamnosus on Salmonella lipopolysaccharide-induced inflammation and epithelial barrier dysfunction in a co-culture model using Caco-2/peripheral blood mononuclear cells

J Med Microbiol. 2010 May;59(Pt 5):573-579. doi: 10.1099/jmm.0.009662-0. Epub 2010 Jan 28.

Abstract

In this study, we investigated the anti-inflammatory and reinforcing barrier effects of Lactobacillus casei subsp. rhamnosus (Lcr35) on Caco-2 intestinal epithelial cells already exposed to Salmonella LPS. Using the Transwell co-culture model, Salmonella LPS was apically added to polarized Caco-2 cells co-cultured with peripheral blood mononuclear cells (PBMCs) in the basolateral compartment. LPS-stimulated Caco-2 cells were incubated with Lcr35 for 1, 6, 24 or 48 h. Apical inoculation of Lcr35 after 48 h significantly inhibited the basolateral secretion of interleukin-8 (IL-8) in the Caco-2/PBMC co-culture. The PCR analysis showed that Lcr35 significantly downregulated mRNA expression of monocyte chemoattractant protein 1 (MCP-1) (P<0.05) and had a trend of decreasing mRNA expression of IL-8 (P=0.05), but did not alter mRNA expression of transforming growth factor-beta1 in LPS-stimulated Caco-2 cells at 48 h after addition of Lcr35. Compared to non-LPS-pretreated controls, transepithelial electrical resistance (TEER) of the polarized Caco-2 cell monolayers pretreated with LPS for 48 h was decreased by 9.9 % (P<0.05). Additionally, compared to those cells only treated with LPS, apical co-incubation with Lcr35 showed biphasic TEER levels increased by 12.1 % (P<0.001), 5.7 % (P<0.05) and 86.8 % (P<0.001) in the Caco-2 cell monolayers compared to those without Lcr35 treatment after 1, 6 and 48 h, respectively. In conclusion, Lcr35 can exert anti-inflammatory effects and ameliorate barrier dysfunction in the Salmonella LPS-pretreated inflamed intestinal epithelium in vitro.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Caco-2 Cells
  • Chemokine CCL2 / biosynthesis
  • Coculture Techniques
  • Down-Regulation
  • Electric Impedance
  • Epithelial Cells / drug effects
  • Epithelial Cells / immunology*
  • Epithelial Cells / microbiology*
  • Gene Expression
  • Humans
  • Inflammation*
  • Interleukin-8 / metabolism
  • Lacticaseibacillus casei / physiology*
  • Leukocytes, Mononuclear / immunology
  • Lipopolysaccharides / immunology
  • Lipopolysaccharides / isolation & purification
  • Lipopolysaccharides / toxicity*
  • Salmonella / chemistry*
  • Transforming Growth Factor beta1 / biosynthesis

Substances

  • CCL2 protein, human
  • Chemokine CCL2
  • Interleukin-8
  • Lipopolysaccharides
  • Transforming Growth Factor beta1