Effects of experimental weight perturbation on skeletal muscle work efficiency, fuel utilization, and biochemistry in human subjects
Effects of experimental weight perturbation on skeletal muscle work efficiency, fuel utilization, and biochemistry in human subjects
复制标题
DOI：
10.1152/ajpregu.00053.2009
复制
发表时间：
2010-01-01
影响因子：
2.8
通讯作者：
Rosenbaum, Michael
中科院分区：
文献类型：
--
作者：
Goldsmith, Rochelle;Joanisse, Denis R.;Rosenbaum, Michael
Goldsmith R、Joanisse DR、Gallagher D、Pavlovich K、Shamoon E、Leibel RL、Rosenbaum M。实验体重扰动对人体骨骼肌工作效率、燃料利用率和生物化学的影响。 Am J Physiol Regul Integr Comp Physiol 298：R79-R88，2010。首次发表于 2009 年 11 月 4 日； doi:10.1152/ajpregu.00053.2009.-将体重维持在瘦或肥胖个体“习惯”水平之上或之下 10% 会导致低水平体力活动消耗的能量（非静息能量消耗，NREE）分别增加或减少。这些变化大于体重或成分变化所能解释的变化，主要是由于低发电水平下骨骼肌工作效率的变化所致。我们对股外侧肌针活检样本进行了生化分析，以确定体重改变的维持是否与骨骼肌组织形态学的变化相关。我们发现，维持体重减轻 10% 与糖酵解（磷酸果糖激酶，PFK）酶活性显着下降相关，特别是糖酵解与氧化（细胞色素 C 氧化酶，COX）酶活性的比率，而与线粒体密度、呼吸链活性或燃料运输相关的酶活性没有显着变化；或骨骼肌纤维类型或糖原储备。减肥后受试者 PFK/COX 活性比率的分数变化与全身呼吸交换比 (RER) 的变化以及低工作负荷下骨骼肌机械效率的测量（踩自行车产生 10 或 25 W 的功率）显着相关。因此，全身骨骼肌生物化学的可预测变化伴随着体重改变的维持，并解释了体重减轻时骨骼肌工作效率和燃料利用率差异的很大一部分。
Goldsmith R, Joanisse DR, Gallagher D, Pavlovich K, Shamoon E, Leibel RL, Rosenbaum M. Effects of experimental weight perturbation on skeletal muscle work efficiency, fuel utilization, and biochemistry in human subjects. Am J Physiol Regul Integr Comp Physiol 298: R79-R88, 2010. First published November 4, 2009; doi:10.1152/ajpregu.00053.2009.-Maintenance of a body weight 10% above or below that "customary" for lean or obese individuals results in respective increases or decreases in the energy expended in low levels of physical activity (nonresting energy expenditure, NREE). These changes are greater than can be accounted for by the altered body weight or composition and are due mainly to altered skeletal muscle work efficiency at low levels of power generation. We performed biochemical analysis of vastus lateralis muscle needle biopsy samples to determine whether maintenance of an altered body weight was associated with changes in skeletal muscle histomorphology. We found that the maintenance of a 10% reduced body weight was associated with significant declines in glycolytic (phosphofructokinase, PFK) enzyme activity and, in particular, in the ratio of glycolytic to oxidative (cytochrome c oxidase, COX) enzyme activity without significant changes in the activities of enzymes relevant to mitochondrial density, respiratory chain activity, or fuel transport; or in skeletal muscle fiber type or glycogen stores. The fractional change in the ratio of PFK/COX activity in subjects following weight loss was significantly correlated with changes in the systemic respiratory exchange ratio (RER) and measures of mechanical efficiency of skeletal muscle at low workloads (pedaling a bicycle to generate 10 or 25 W of power). Thus, predictable changes in systemic skeletal muscle biochemistry accompany the maintenance of an altered body weight and account for a significant portion of the variance in skeletal muscle work efficiency and fuel utilization at reduced body weight.