Brenmoehl Julia, Meyer Zianka, Walz Christina, Ohde Daniela, Hoeflich Andreas
Workgroup Endocrinology of Farm Animals, Research Institute for Farm Animal Biology (FBN), 18196 Dummerstorf, Germany.
Cells. 2024 Dec 21;13(24):2123. doi: 10.3390/cells13242123.
Metabolic flexibility describes the capability to switch between oxidative fuels depending on their availability during diet or exercise. In a previous study, we demonstrated that in response to training, marathon (DUhTP) mice, paternally selected for high treadmill performance, are metabolically more flexible than unselected control (DUC) mice. Since exercise-associated metabolic flexibility can be assessed by indirect calorimetry or partially by circulating lactate concentrations, we investigated these parameters in DUhTP and DUC mice. Therefore, males of both lines completed a three-week high-speed treadmill training or were physically inactive (sedentary) before being placed in a metabolic cage for three days (one day of acclimatization, two days with monitoring), measuring CO and O to calculate respiratory quotient (RQ) and fatty acid oxidation (FATox). Circulating blood lactate concentrations were determined. Training resulted in a lower RQ in DUhTP and an increased RQ in DUC mice compared to their sedentary counterparts. Increased FATox rates and lower lactate concentrations were observed in exercised DUhTP but not in DUC mice, indicating a shift to oxidative metabolism in DUhTP and a glycolytic one in DUC mice. Therefore, improved metabolic flexibility in DUhTP mice is verifiable up to three days after training.
代谢灵活性描述了根据饮食或运动期间氧化燃料的可用性在不同氧化燃料之间切换的能力。在之前的一项研究中，我们证明，因跑步机性能高而被父系选择的马拉松（DUhTP）小鼠，在接受训练后，其代谢灵活性比未经过选择的对照（DUC）小鼠更高。由于运动相关的代谢灵活性可以通过间接测热法或部分通过循环乳酸浓度来评估，我们在DUhTP和DUC小鼠中研究了这些参数。因此，两个品系的雄性小鼠在被置于代谢笼中三天（一天适应期，两天监测期）之前，都完成了为期三周的高速跑步机训练或处于不活动状态（久坐），期间测量二氧化碳和氧气以计算呼吸商（RQ）和脂肪酸氧化（FATox）。同时测定循环血乳酸浓度。与久坐的同系小鼠相比，训练使DUhTP小鼠的RQ降低，使DUC小鼠的RQ升高。在运动后的DUhTP小鼠中观察到FATox率增加和乳酸浓度降低，而在DUC小鼠中未观察到，这表明DUhTP小鼠向氧化代谢转变，而DUC小鼠向糖酵解代谢转变。因此，DUhTP小鼠代谢灵活性的改善在训练后三天内都是可验证的。
