Name: respirometric oxidative phosphorylation assessment in saponin-permeabilized cardiac fibers
Uploaded: 2011-02-28T18:30:00
Description: Watch this Scientific Journal Video about Respirometric Oxidative Phosphorylation Assessment in Saponin-permeabilized Cardiac Fibers at JoVE.com

This study was supported by the Canadian Institutes of Health Research and Genome Canada. JS holds salary support awards from the Alberta Heritage Foundation for Medical Research, Heart and Stroke Foundation of Canada and the Canadian Diabetes Association. The laboratory would like to acknowledge the technical assistance of Oroboros Instruments during the acquisition of the saponin-permeabilized fiber technique.

1. Reagent Preparation
<ol>
<li>The relaxation and preservation solution (RP Solution) is prepared as previously described with minor modifications1. Briefly, the RP Solution consists of 2.77mM CaK2EGTA, 7.23mM K2EGTA, 20mM imidazole, 0.5mM dithiothreitol, 20mM taurine, 50mM K-MES, 6.56 MgCl2, 5.7mM ATP, 14.3mM phosphocreatine, pH 7.1, adjusted at room temperature (RT). Filter the solution through a 0.45-&mu;m filter to sterilize. Divide into 15 mL portions (Falcon polypr...

<ol>
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R., Winkler, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Use+of+saponin-permeabilized+muscle+fibers+for+the+diagnosis+of+mitochondrial+diseases.">Use of saponin-permeabilized muscle fibers for the diagnosis of mitochondrial diseases.</a> Biofactors. 7, 221-223 (1998).</li><li>Gnaiger, E., Dykens, J., Will, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Polarographic+oxygen+sensors,+the+oxygraph+and+high-resolution+respirometry+to+assess+mitochondrial+function.">Polarographic oxygen sensors, the oxygraph and high-resolution respirometry to assess mitochondrial function.</a> Drug-Induced Mitochondrial Dysfunction. , 327-352 (2008).</li></ol>

The saponin-permeabilized cardiac fiber technique offers a unique compromise between in vitro and in vivo assessment of mitochondrial OXPHOS oxygen consumption. Advantages of this technique include increased physiological relevance in comparison to isolated mitochondria as cellular architecture is preserved. While the plasma membrane is degraded, intracellular membrane structures including mitochondria12, 14, sarcoplasmic reticulum14, myofilaments and the cytoskeleton 1, 17<...

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		<div>
		<table border="1">
		<thead>
		<tr>
		<th>Material Name</th>
		<th>Type</th>
		<th>Company</th>
		<th>Catalogue Number</th>
		<th>Comment</th>
		</tr>
		</thead>
		<tbody>
		
<tr>
<td>100% Ethanol</td>
<td>&nbsp;</td>
<td>Fisher Scientific</td>
<td>HC600</td>
<td>&nbsp;</td>
<tr>
<td>70% Ethanol</td>
<td>&nbsp;</td>
<td>Fisher Scientific</td>
<td>HC-1000</td>
<td>&nbsp;</td>
<tr>
<td>Adenosine 5&#x2032;-diphosphate monopotassium salt dihydrate (ADP)</td>
<td>&nbsp;</td>
<td>Sigma</td>
<td>A5285</td>
<td>&nbsp;</td>
<tr>
<td>Albumin from bovine serum essentially fatty acid&#x2013;free</td>
<td>&nbsp;</td>
<td>Sigma</td>
<td>A-6003</td>
<td>&nbsp;</td>
<tr>
<td>Antimycin A</td>
<td>&nbsp;</td>
<td>Sigma</td>
<td>A8674</td>
<td>&nbsp;</td>
<tr>
<td>Ascobic acid</td>
<td>&nbsp;</td>
<td>Sigma</td>
<td>A4403</td>
<td>&nbsp;</td>
<tr>
<td>Adenosine 5&#x2032;-triphosphate disodium salt hydrate (ATP)</td>
<td>&nbsp;</td>
<td>Sigma</td>
<td>A2383</td>
<td>&nbsp;</td>
<tr>
<td>Atractyloside</td>
<td>&nbsp;</td>
<td>Sigma</td>
<td>A6882</td>
<td>&nbsp;</td>
<tr>
<td>Calcium carbonate</td>
<td>&nbsp;</td>
<td>Sigma</td>
<td>C4830</td>
<td>&nbsp;</td>
<tr>
<td>Carbonyl cyanide p-(trifluoromethoxy) phenylhydrazone (FCCP)</td>
<td>&nbsp;</td>
<td>Sigma</td>
<td>C2920</td>
<td>&nbsp;</td>
<tr>
<td>Cytochrome c</td>
<td>&nbsp;</td>
<td>Sigma</td>
<td>C7752</td>
<td>&nbsp;</td>
<tr>
<td>Digitonin</td>
<td>&nbsp;</td>
<td>Sigma</td>
<td>D141</td>
<td>&nbsp;</td>
<tr>
<td>Dithiothreitol</td>
<td>&nbsp;</td>
<td>Sigma</td>
<td>D9779</td>
<td>&nbsp;</td>
<tr>
<td>Ethylene glycol-bis-(2-aminoethylether)-N,N,N&#x2032;,N&#x2032;-tetraacetic acid (EGTA)</td>
<td>&nbsp;</td>
<td>Sigma</td>
<td>E4378</td>
<td>&nbsp;</td>
<tr>
<td>Glutamic acid</td>
<td>&nbsp;</td>
<td>Sigma</td>
<td>27647</td>
<td>&nbsp;</td>
<tr>
<td>HEPES</td>
<td>&nbsp;</td>
<td>Sigma</td>
<td>H4034</td>
<td>&nbsp;</td>
<tr>
<td>Imidazole</td>
<td>&nbsp;</td>
<td>Sigma</td>
<td>I5513</td>
<td>&nbsp;</td>
<tr>
<td>Ketamine</td>
<td>&nbsp;</td>
<td>Pfizer</td>
<td>&nbsp;</td>
<td>Ketaset</td>
</tr>
<tr>
<td>Lactobionic acid</td>
<td>&nbsp;</td>
<td>Sigma</td>
<td>153516</td>
<td>&nbsp;</td>
<tr>
<td>Magnesium chloride (MgCl2)</td>
<td>&nbsp;</td>
<td>Sigma</td>
<td>M9272</td>
<td>&nbsp;</td>
<tr>
<td>Magnesium chloride hexahydrate (MgCl2&#x2219;6H2O)</td>
<td>&nbsp;</td>
<td>Sigma</td>
<td>M9272</td>
<td>&nbsp;</td>
<tr>
<td>Malic acid</td>
<td>&nbsp;</td>
<td>Sigma</td>
<td>M1000</td>
<td>&nbsp;</td>
<tr>
<td>MES</td>
<td>&nbsp;</td>
<td>Sigma</td>
<td>M3671</td>
<td>&nbsp;</td>
<tr>
<td>N,N,N&#x2019;,N&#x2019;-Tetramethyl- pphenylenediamine Dihydrochloride (TMPD)</td>
<td>&nbsp;</td>
<td>Sigma</td>
<td>T3134</td>
<td>&nbsp;</td>
<tr>
<td>Oligomycin</td>
<td>&nbsp;</td>
<td>Sigma</td>
<td>O4876</td>
<td>&nbsp;</td>
<tr>
<td>Phosphocreatine</td>
<td>&nbsp;</td>
<td>Sigma</td>
<td>P7936</td>
<td>&nbsp;</td>
<tr>
<td>Potassium Chloride</td>
<td>&nbsp;</td>
<td>Sigma</td>
<td>P9541</td>
<td>&nbsp;</td>
<tr>
<td>Potassium Hydroxide</td>
<td>&nbsp;</td>
<td>Sigma</td>
<td>P5958</td>
<td>&nbsp;</td>
<tr>
<td>Potassium cyanide</td>
<td>&nbsp;</td>
<td>Fluka</td>
<td>60178</td>
<td>&nbsp;</td>
<tr>
<td>Potassium phosphate monobasic</td>
<td>&nbsp;</td>
<td>Sigma</td>
<td>P5655</td>
<td>&nbsp;</td>
<tr>
<td>Rotenone</td>
<td>&nbsp;</td>
<td>Sigma</td>
<td>R8875</td>
<td>&nbsp;</td>
<tr>
<td>Saponin</td>
<td>&nbsp;</td>
<td>Sigma</td>
<td>47036</td>
<td>&nbsp;</td>
<tr>
<td>Sodium Pentobarbital</td>
<td>&nbsp;</td>
<td>Ceva Sante Animale</td>
<td>1715 138</td>
<td>Conc. 54.7 mg/ml</td>
</tr>
<tr>
<td>Sodium pyruvate</td>
<td>&nbsp;</td>
<td>Sigma</td>
<td>P2256</td>
<td>&nbsp;</td>
<tr>
<td>Succinic acid</td>
<td>&nbsp;</td>
<td>Sigma</td>
<td>S3674</td>
<td>&nbsp;</td>
<tr>
<td>Sucrose</td>
<td>&nbsp;</td>
<td>Sigma</td>
<td>S7903</td>
<td>&nbsp;</td>
<tr>
<td>Taurine</td>
<td>&nbsp;</td>
<td>Sigma</td>
<td>T8691</td>
<td>&nbsp;</td>
<tr>
<td>Xylazine</td>
<td>&nbsp;</td>
<td>Bayer</td>
<td>&nbsp;</td>
<td>Rompun</td>
</tr>
<tr>
<td>ddH2O</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<tr>
<td>Ice</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<tr>
<td>Oroboros Oxygraph-2k</td>
<td>&nbsp;</td>
<td>Oroboros Instruments</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<tr>
<td>Kimwipes</td>
<td>&nbsp;</td>
<td>VWR</td>
<td>21905-026</td>
<td>&nbsp;</td>
<tr>
<td>15ml polypropylene centrifuge tubes</td>
<td>&nbsp;</td>
<td>VWR</td>
<td>89004-368</td>
<td>&nbsp;</td>
<tr>
<td>50ml polypropylene centrifuge tubes</td>
<td>&nbsp;</td>
<td>VWR</td>
<td>89004-364</td>
<td>&nbsp;</td>
<tr>
<td>Straight Jewelers Forceps</td>
<td>&nbsp;</td>
<td>George Tiemann &amp; Co.</td>
<td>160-50B</td>
<td>&nbsp;</td>
<tr>
<td>Curved Jewelers Forceps</td>
<td>&nbsp;</td>
<td>George Tiemann &amp; Co.</td>
<td>160-57B</td>
<td>&nbsp;</td>
<tr>
<td>Straight Surgery Scissors</td>
<td>&nbsp;</td>
<td>George Tiemann &amp; Co.</td>
<td>105-402</td>
<td>&nbsp;</td>
<tr>
<td>Sterile Surgical Blade</td>
<td>&nbsp;</td>
<td>VWR</td>
<td>BD371610</td>
<td>&nbsp;</td>
<tr>
<td>0.45-&mu;m Syringe filters</td>
<td>&nbsp;</td>
<td>VWR</td>
<td>CA28145-485</td>
<td>&nbsp;</td>
<tr>
<td>pH meter</td>
<td>&nbsp;</td>
<td>VWR</td>
<td>CA11388-308</td>
<td>&nbsp;</td>
<tr>
<td>Glass Petri dishes</td>
<td>&nbsp;</td>
<td>VWR</td>
<td>89000-300</td>
<td>&nbsp;</td>
<tr>
<td>12-well Polystyrene Tissue Culture Plates</td>
<td>&nbsp;</td>
<td>VWR</td>
<td>82050-926</td>
<td>&nbsp;</td>
<tr>
<td>Plate Stirrer</td>
<td>&nbsp;</td>
<td>VWR</td>
<td>97042-594</td>
<td>&nbsp;</td>
<tr>
<td>Fisherbrand Microbars</td>
<td>&nbsp;</td>
<td>Fisher Scientific</td>
<td>14-511-67</td>
<td>&nbsp;</td>
<tr>
<td>Weigh Scale</td>
<td>&nbsp;</td>
<td>VWR</td>
<td>CA11278-162</td>
<td>&nbsp;</td>
<tr>
<td>10&mu;l Hamilton Micro Syringe</td>
<td>&nbsp;</td>
<td>Fisher Scientific</td>
<td>14-815-1</td>
<td>&nbsp;</td>
<tr>
<td>25&#x03BC;l Hamilton Micro Syringe</td>
<td>&nbsp;</td>
<td>Fisher Scientific</td>
<td>14-824-7</td>
<td>&nbsp;</td>
<tr>
<td>50&mu;l Hamilton Micro Syringe</td>
<td>&nbsp;</td>
<td>Fisher Scientific</td>
<td>14-824-5</td>
<td>&nbsp;</td>
<tr>
<td>Nalgene Squeeze Bottles</td>
<td>&nbsp;</td>
<td>Wilkem Scientific</td>
<td>LNA2407-1000</td>
<td>&nbsp;</td>
<tr>
<td>Polystyrene Weighing Dishes</td>
<td>&nbsp;</td>
<td>VWR</td>
<td>89106-750</td>
<td>&nbsp;</td>
<tr>
<td>Dissecting Microscope</td>
<td>&nbsp;</td>
<td>Olympus</td>
<td>&nbsp;</td>
<td>&nbsp;</td>		</tbody>
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respirometric oxidative phosphorylation assessment in saponin-permeabilized cardiac fibers

Investigation of mitochondrial function represents an important parameter of cardiac physiology as mitochondria are involved in energy metabolism, oxidative stress, apoptosis, aging, mitochondrial encephalomyopathies and drug toxicity. Given this, technologies to measure cardiac mitochondrial function are in demand. One technique that employs an integrative approach to measure mitochondrial function is respirometric oxidative phosphorylation (OXPHOS) analysis.
The principle of respirometric OXPHOS assessment is centered around measuring oxygen concentration utilizing a Clark electrode. As the permeabilized fiber bundle consumes oxygen, oxygen concentration in the closed chamber declines. Using selected substrate-inhibitor-uncoupler titration protocols, electrons are provided to specific sites of the electron transport chain, allowing evaluation of mitochondrial function. Prior to respirometric analysis of mitochondrial function, mechanical and chemical preparatory techniques are utilized to permeabilize the sarcolemma of muscle fibers. Chemical permeabilization employs saponin to selectively perforate the cell membrane while maintaining cellular architecture.
This paper thoroughly describes the steps involved in preparing saponin-skinned cardiac fibers for oxygen consumption measurements to evaluate mitochondrial OXPHOS. Additionally, troubleshooting advice as well as specific substrates, inhibitors and uncouplers that may be used to determine mitochondria function at specific sites of the electron transport chain are provided. Importantly, the described protocol may be easily applied to cardiac and skeletal tissue of various animal models and human samples.

Watch this Scientific Journal Video about Respirometric Oxidative Phosphorylation Assessment in Saponin-permeabilized Cardiac Fibers at JoVE.com

Respirometric Oxidative Phosphorylation Assessment in Saponin-permeabilized Cardiac Fibers

Saponin-permeabilized fiber preparation in conjunction with respirometric oxidative phosphorylation analysis provides integrative assessment of mitochondrial function. Mitochondrial respiration in physiological and pathological states can reflect various regulatory influences including mitochondrial interactions, morphology and biochemistry.

Investigation of mitochondrial function represents an important parameter of cardiac physiology as mitochondria are involved in energy metabolism, ...

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