Regular endurance exercise improves the diminished hepatic carnitine status in mice fed a high-fat diet

Mol Nutr Food Res. 2011 Sep;55 Suppl 2:S193-202. doi: 10.1002/mnfr.201100040. Epub 2011 Jul 19.

Abstract

Scope: Metabolic stress induced by chronic high-fat (HF) diet feeding or genetically induced diabetes impairs carnitine status. Herein, we tested the hypothesis that regular endurance exercise (EE) improves the HF diet-induced impairment of carnitine status through stimulating the expression of hepatic genes involved in carnitine synthesis and uptake.

Methods and results: Eighteen male C57BL/6 mice were assigned to three groups: group S received a standard diet, group HF received a HF diet, and group HF+EE received an HF diet and was regularly exercised on a treadmill. After 10 wk, mice of the HF and the HF+EE groups were highly obese and insulin resistant compared with mice of the S group (p<0.05), but mice of the HF+EE group were less insulin resistant than those of the HF group (p<0.05). The HF group had lower carnitine concentrations and mRNA and protein levels of genes involved in carnitine synthesis and uptake in the liver than the S group (p<0.05), whereas these parameters did not differ between the S group and the HF+EE group.

Conclusion: These findings indicate that regular EE reverses an HF diet-induced impairment of hepatic carnitine content by stimulating hepatic carnitine synthesis and uptake.

MeSH terms

  • Acetylcarnitine / blood
  • Animals
  • Body Weight
  • Carnitine / genetics
  • Carnitine / metabolism*
  • Diet, High-Fat*
  • Fatty Acids / metabolism
  • Gene Expression Regulation
  • Glucose Intolerance
  • Homeostasis
  • Insulin Resistance
  • Liver / metabolism*
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Muscle, Skeletal / metabolism
  • Obesity / metabolism
  • PPAR alpha / genetics
  • Physical Conditioning, Animal
  • Physical Endurance*
  • RNA, Messenger

Substances

  • Fatty Acids
  • PPAR alpha
  • RNA, Messenger
  • Acetylcarnitine
  • Carnitine