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

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.