Institute of Animal Nutrition and Nutrition Physiology, Justus-Liebig-University Giessen, Giessen, Germany.
Mol Nutr Food Res. 2011 Sep;55 Suppl 2:S193-202. doi: 10.1002/mnfr.201100040. Epub 2011 Jul 19.
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.
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.
These findings indicate that regular EE reverses an HF diet-induced impairment of hepatic carnitine content by stimulating hepatic carnitine synthesis and uptake.
慢性高脂肪(HF)饮食喂养或遗传诱导的糖尿病引起的代谢应激会损害肉碱状态。在此,我们通过刺激参与肉碱合成和摄取的肝脏基因的表达来测试以下假设,即有规律的耐力运动(EE)可以改善 HF 饮食引起的肉碱状态受损。
18 只雄性 C57BL/6 小鼠被分为三组:S 组接受标准饮食,HF 组接受 HF 饮食,HF+EE 组接受 HF 饮食并在跑步机上定期运动。10 周后,HF 组和 HF+EE 组的小鼠与 S 组相比,肥胖和胰岛素抵抗程度更高(p<0.05),但 HF+EE 组的胰岛素抵抗程度低于 HF 组(p<0.05)。HF 组的肉碱浓度以及肝脏中参与肉碱合成和摄取的基因的 mRNA 和蛋白水平均低于 S 组(p<0.05),而 S 组和 HF+EE 组之间这些参数没有差异。
这些发现表明,有规律的 EE 通过刺激肝脏肉碱合成和摄取,可逆转 HF 饮食引起的肝肉碱含量降低。