Fletcher 2014 Med Sci Sports Exerc
| Fletcher JA, Meers GM, Linden MA, Kearney ML, Morris EM, Thyfault JP, Rector RS (2014) Impact of various exercise modalities on hepatic mitochondrial function. Med Sci Sports Exerc 46:1089-97. |
Fletcher JA, Meers GM, Linden MA, Kearney ML, Morris EM, Thyfault JP, Rector RS (2014) Med Sci Sports Exerc
Abstract: Hepatic mitochondrial adaptations to exercise are largely unknown. In this study, we sought to determine the effects of various exercise modalities on measures of hepatic mitochondrial function and metabolism.
Male Sprague-Dawley rats were randomly assigned (n = 8-10 per group) into sedentary (SED), voluntary wheel running (VWR), VWR with food pulled during the dark cycle (VMR-OF), treadmill endurance exercise (TM-END; 30 m·min, 12% gradient, 60 min·d, 5 d·wk), or treadmill interval sprint training (TM-IST; 50 m·min, 12% gradient, 6 × 2.5 min bouts, 5 d·wk) groups for a 4-wk intervention.
Hepatic mitochondrial state 3 and maximal uncoupled respiration were significantly (p< 0.05) increased in all four exercise groups compared with SED animals. In addition, hepatic mitochondrial [1-C] pyruvate oxidation to CO2, an index of pyruvate dehydrogenase (PDH) activity, was significantly increased in VWR-OF, TM-END, and TM-IST rats (p<0.05), whereas exercise-induced increases in [2-C] pyruvate oxidation and [1-C] palmitate oxidation to CO2 did not reach statistical significance. Hepatic mitochondrial sirtuin 3 protein content, which putatively increases activity of mitochondrial proteins, was elevated in the VWR, VWR-OF, and TM-END groups (p<0.05). In addition, only VWR-OF animals experienced increases in hepatic cytochrome c protein content and phosphoenolpyruvate carboxykinase mRNA, whereas PGC-1α mRNA expression and phospho-CREB protein content was increased in VWR-OF and TM-END groups.
Four weeks of exercise training, regardless of exercise modality, significantly increased hepatic mitochondrial respiration and evoked other unique improvements in mitochondrial metabolism that do not appear to be dependent on increases in mitochondrial content. • Keywords: Exercise, Hepatic mitochondria, Fatty acid oxydation, Mitochondrial function
• O2k-Network Lab: US MO Columbia Rector RS
Labels: MiParea: Respiration, Exercise physiology;nutrition;life style
Organism: Rat
Tissue;cell: Liver
Preparation: Isolated mitochondria
Coupling state: LEAK, OXPHOS, ET
Pathway: N, S, NS
HRR: Oxygraph-2k
