Nondigestible oligosaccharides exert nonprebiotic effects on intestinal epithelial cells enhancing the immune response via activation of TLR4-NFκB

Mol Nutr Food Res. 2014 Feb;58(2):384-93. doi: 10.1002/mnfr.201300296. Epub 2013 Sep 3.


Scope: Prebiotic effects of non absorbable glucids depend mainly on digestion by the colonic microbiota. Our aim was to assess nonprebiotic, direct effects of 4 prebiotics, namely fructooligosaccharides, inulin, galactooligosaccharides, and goat's milk oligosaccharides on intestinal epithelial cells.

Methods and results: Prebiotics were tested in intestinal epithelial cell 18 (IEC18), HT29, and Caco-2 cells. Cytokine secretion was measured by ELISA and modulated with pharmacological probes and gene silencing. Prebiotics induced the production of growth-related oncogene, (GROα), monocyte chemoattractant protein 1 (MCP-1), and macrophage inflammatory protein 2 (MIP2) in IEC18 cells, with an efficacy that was 50-80% that of LPS. Prebiotics did not change RANTES expression, which was robustly induced by LPS in IEC18 cells. Cytokine secretion was suppressed by Bay11-7082, an inhibitor of IκB-α phosphorylation. The response was markedly decreased by Myd88 or TLR4 gene knockdown. Prebiotics also elicited cytokine production in HT29 but not in Caco-2 cells, consistent with reduced and vestigial expression of TLR4 in these cell lines, respectively. Prebiotic-induced MCP-1 secretion was reduced also in colonic explants from TLR4 KO mice compared with the controls.

Conclusions: We conclude that prebiotics are TLR4 ligands in intestinal epithelial cells and that this may be a relevant mechanism for their in vivo effects.

Keywords: Cytokines; Intestinal epithelial cells; NF-κB; Prebiotic; Toll-like receptor 4.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Caco-2 Cells
  • Chemokine CCL2 / genetics
  • Chemokine CCL2 / metabolism
  • Epithelial Cells / drug effects*
  • Female
  • Gene Knockdown Techniques
  • HT29 Cells
  • Humans
  • Intestines / cytology*
  • Intestines / drug effects
  • Intestines / microbiology
  • Inulin / pharmacology
  • Lipopolysaccharides / adverse effects
  • Male
  • Mice, Inbred C57BL
  • Microbiota
  • Myeloid Differentiation Factor 88 / genetics
  • Myeloid Differentiation Factor 88 / metabolism
  • NF-kappa B / genetics
  • NF-kappa B / metabolism*
  • Oligosaccharides / pharmacology*
  • Prebiotics*
  • Toll-Like Receptor 4 / genetics
  • Toll-Like Receptor 4 / metabolism*


  • Ccl2 protein, mouse
  • Chemokine CCL2
  • Lipopolysaccharides
  • Myd88 protein, mouse
  • Myeloid Differentiation Factor 88
  • NF-kappa B
  • Oligosaccharides
  • Prebiotics
  • TLR4 protein, human
  • Toll-Like Receptor 4
  • fructooligosaccharide
  • Inulin