Polycyclic Aromatic Hydrocarbons Potentiate High-Fat Diet Effects on Intestinal Inflammation

Toxicol Lett. 2010 Jul 15;196(3):161-7. doi: 10.1016/j.toxlet.2010.04.010. Epub 2010 Apr 20.

Abstract

We demonstrate that intestinal inflammation caused by high-fat diet is increased by the environmental contaminant benzo[a]pyrene. Our in vivo results indicate that a high-fat diet (HFD) induces a pre-diabetic state in mice compared with animals fed normal chow. HFD increased IL-1betamRNA concentration in the jejunum, colon, and liver, and TNFalpha was increased in the colon and strongly increased in the liver. HFD also increased the expression of other genes related to type 2 diabetes, such as the uncoupling protein UCP2, throughout the bowel and liver, but not in the colon. The treatment of HFD with BaP enhanced the expression of IL-1beta in the liver and TNFalpha throughout the bowel and in the liver. Adding BaP to the diet also caused a significant decrease in the expression of the incretin glucagon-like peptide 1, which plays an important role in insulin secretion. Our results suggest that intestinal inflammation may be involved in the onset of type 2 diabetes and that chronic exposure to environmental polycyclic aromatic hydrocarbons can increase the risk of type 2 diabetes by inducing pro-inflammatory cytokine production.

MeSH terms

  • Animals
  • Benzo(a)pyrene / toxicity*
  • Diabetes Mellitus, Type 2 / etiology*
  • Dietary Fats / toxicity*
  • Enteritis / etiology*
  • Glucagon-Like Peptide 1 / analysis
  • Insulin / blood
  • Interleukin-10 / analysis
  • Interleukin-1beta / genetics
  • Ion Channels / genetics
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Mitochondrial Proteins / genetics
  • Tumor Necrosis Factor-alpha / genetics
  • Uncoupling Protein 2
  • Weight Gain / drug effects

Substances

  • Dietary Fats
  • Insulin
  • Interleukin-1beta
  • Ion Channels
  • Mitochondrial Proteins
  • Tumor Necrosis Factor-alpha
  • Ucp2 protein, mouse
  • Uncoupling Protein 2
  • Interleukin-10
  • Benzo(a)pyrene
  • Glucagon-Like Peptide 1