Protective effects of lactic acid bacteria on gut epithelial barrier dysfunction are Toll like receptor 2 and protein kinase C dependent

Food Funct. 2020 Feb 26;11(2):1230-1234. doi: 10.1039/c9fo02933h.

Abstract

Lactic acid bacteria (LAB) are recognized for support of host gut homeostasis but the precise mechanisms remain to be identified. LABs interact with Toll-like receptors (TLRs) which might stimulate barrier function of gut epithelial cells. We previously identified six TLR2-signalling LAB strains. As TLR2 is involved in barrier-function enhancement in gut-epithelium, the epithelial barrier-protective effect of these TLR2-signalling strains was studied by using T84 human colorectal cancer cell monolayer as an in vitro gut epithelial barrier model. The protein kinase C (PKC) dependent barrier disruptor A23187 and mitogen-activated protein kinase dependent barrier stressor deoxynivalenol were tested to determine which pathways LAB influenced. We found that exclusively the PKC dependent disruption was prevented by the selected TLR2-signalling LAB strains. This study suggests that TLR2 is a pivotal epithelial barrier modulator, and provides novel insight in the molecular mechanisms by which LAB contribute to intestinal health.

MeSH terms

  • Calcimycin / pharmacology
  • Cell Line, Tumor
  • Electric Impedance
  • Humans
  • Intestinal Mucosa / cytology
  • Intestinal Mucosa / drug effects*
  • Lactobacillales / physiology*
  • Models, Biological
  • Probiotics / pharmacology*
  • Protein Kinase C / metabolism*
  • Toll-Like Receptor 2 / metabolism*
  • Trichothecenes / pharmacology

Substances

  • TLR2 protein, human
  • Toll-Like Receptor 2
  • Trichothecenes
  • Calcimycin
  • Protein Kinase C
  • deoxynivalenol