Perry 2014 Abstract MiP2014
|Evaluation of critical experimental parameters for assessing mitochondrial bioenergetics in permeabilized myofibers.|
Respirometric and fluorometric approaches for assessing the regulation of submaximal and maximal (‘capacity’) oxidative phosphorylation and mitochondrial oxidant emission respectively, in permeabilized myofibers, have been documented extensively [1-3 and other]. Optimizing such bioenergetic measurements requires control of critical experimental parameters including partial pressure of oxygen (pO2), temperature and assay media composition (ionic balance, oxidant scavenging capacity, etc.) [1-4]. Recently, myofiber contraction, analogous to ADP-induced rigor, has also been reported to alter respiratory sensitivity to ADP (K’m) and maximal respiration in a temperature-sensitive manner which can be prevented with myosin-ATPase inhibitors [3,4].
The purpose of this presentation is to stimulate debate regarding the need for standardizing specific parameters throughout the field vs the value of customizing certain parameters to each hypothesis. An emphasis will be placed on the manner by which each factor affects mitochondrial bioenergetics in permeabilized myofibers.
Labels: MiParea: Respiration, Instruments;methods
Organism: Human Tissue;cell: Skeletal muscle Preparation: Permeabilized tissue
Regulation: ADP, Oxygen kinetics, Temperature Coupling state: OXPHOS
HRR: Oxygraph-2k, O2k-Fluorometer Event: B1, Oral MiP2014
1-School Kinesiology Health Sc, Muscle Health Res Centre, York Univ, Toronto, ON; 2-Dep Human Kinetics, St. Francis Xavier Univ, Antigonish, NS; Canada; 3-Dep Physiol, East Carolina Diabetes Obesity Inst, Greenville, NC, USA. – [email protected]
References and acknowledgements
Supported by: National Institute of Health (USA) and National Science and Engineering Research Council (Canada).
- Gnaiger E (2009) Capacity of oxidative phosphorylation in human skeletal muscle: new perspectives of mitochondrial physiology. Int J Biochem Cell Biol 41:1837–45.
- Pesta D, Gnaiger E (2012) High-resolution respirometry. OXPHOS protocols for human cells and permeabilized fibers from small biopsies of human muscle. Methods Mol Biol 810:25-58.
- Perry CGR, Kane DA, Lanza I, PD Neufer (2013) Methods for assessing mitochondrial function in diabetes. Diabetes 62:1041-52.
- Perry CGR, Kane DA, Lin CT, Kozy R, Cathey B, Lark DS, Kane CL, Brophy PM, Gavin TP, Anderson EJ, Neufer PD (2011) Inhibiting myosin-ATPase reveals a dynamic range of mitochondrial respiratory control in skeletal muscle. Biochem J 437:215-22.