Jacobs 2013b Exp Physiol
|Jacobs R, Díaz V, Meinild AK, Gassmann M, Lundby C (2012) The C57Bl/6 mouse serves as a suitable model of human skeletal muscle mitochondrial function. Exp Physiol 98:908-21.|
Abstract: There is disagreement whether i) differences in mitochondrial function exist across skeletal muscle types, and ii) mouse skeletal muscle mitochondrial function can serve as a valid model for human skeletal muscle mitochondrial function. The aims of this study were to first compare and contrast three different mouse skeletal muscles from one another, and second to identify the mouse muscle that most closely resembles human skeletal muscle respiratory capacity and control. Mouse quadricep (QUADM), soleus (SOLM), and gastrocnemius (GASTM) skeletal muscles were obtained from 8-10 week old healthy mice (n = 8) representing mixed, oxidative, and glycolytic muscle, respectively. Skeletal muscle samples were also collected from young, active, healthy human subjects (n = 8) from the m. vastis lateralis (QUADH). High-resolution respirometry was used to examine mitochondrial function in all skeletal muscle samples and mitochondrial content was quantified with citrate synthase (CS) activity. Mass-specific respiration was higher across all respiratory states in SOLM versus both GASTM and QUADH (p < 0.01). When controlling for mitochondrial content, however, SOLM respiration was actually lower than GASTM and QUADH (p < 0.05 and 0.01, respectively). When comparing respiration capacity across mouse muscle to human, QUADM only exhibited one different respiratory state when compared to QUADH. These results demonstrate that qualitative differences in mitochondria function exist between different mouse skeletal muscles types when respiratory capacity is normalized to mitochondrial content, and that skeletal muscle respiratory capacity in young, healthy QUADM does correspond well with that of young, healthy QUADH.
• Keywords: Comparative physiology, Mitochondrial content
Organism: Human, Mouse Tissue;cell: Skeletal muscle Preparation: Permeabilized tissue