Picard 2011 PLoS One

Has title::Picard M, Taivassalo T, Ritchie D, Wright KJ, Thomas MM, Romestaing C, Hepple RT (2011) Mitochondrial structure and function are disrupted by standard isolation methods. PLoS One 6:e18317.

» [[Has info::PMID: 21512578 Open Access]]

Was written by::Picard M, Was written by::Taivassalo T, Was written by::Ritchie D, Was written by::Wright KJ, Was written by::Thomas MM, Was written by::Romestaing C, Was written by::Hepple RT (Was published in year::2011) Was published in journal::PLoS One

Abstract: [[has abstract::Mitochondria regulate critical components of cellular function via ATP production, reactive oxygen species production, Ca2+ handling and apoptotic signaling. Two classical methods exist to study mitochondrial function of skeletal muscles: isolated mitochondria and permeabilized myofibers. Whereas mitochondrial isolation removes a portion of the mitochondria from their cellular environment, myofiber permeabilization preserves mitochondrial morphology and functional interactions with other intracellular components. Despite this, isolated mitochondria remain the most commonly used method to infer in vivo mitochondrial function. In this study, we directly compared measures of several key aspects of mitochondrial function in both isolated mitochondria and permeabilized myofibers of rat gastrocnemius muscle. Here we show that mitochondrial isolation i) induced fragmented organelle morphology; ii) dramatically sensitized the permeability transition pore sensitivity to a Ca2+ challenge; iii) differentially altered mitochondrial respiration depending upon the respiratory conditions; and iv) dramatically increased H₂O₂ production. These alterations are qualitatively similar to the changes in mitochondrial structure and function observed in vivo after cellular stress-induced mitochondrial fragmentation, but are generally of much greater magnitude. Furthermore, mitochondrial isolation markedly altered electron transport chain protein stoichiometry. Collectively, our results demonstrate that isolated mitochondria possess functional characteristics that differ fundamentally from those of intact mitochondria in permeabilized myofibers. Our work and that of others underscores the importance of studying mitochondrial function in tissue preparations where mitochondrial structure is preserved and all mitochondria are represented.]] • Keywords: has publicationkeywords::Isolated mitochondria, has publicationkeywords::Permeabilized myofibers, has publicationkeywords::ROS

• O2k-Network Lab: Was published by MiPNetLab::CA Montreal Hepple RT, Was published by MiPNetLab::FR Villeurbanne Romestaing C, Was published by MiPNetLab::US FL Gainesville Hepple RT

Labels:

Stress:Injury and adaptation::Oxidative stress;RONS  Organism: Organism::Rat  Tissue;cell: tissue and cell::Skeletal muscle  Preparation: Preparation::Permeabilized tissue, Preparation::Isolated mitochondria 

HRR: Instrument and method::Oxygraph-2k 

• See discussion: Talk:Permeabilized muscle fibers