Effect of temperature on fatty acid metabolism in skeletal muscle mitochondria of untrained and endurance-trained rats - Fig 2

<p><b>Determination of protein levels in skeletal muscle homogenates (A) and mitochondria (B) from control (</b>c<b>) and trained (t) rats. A</b>, Representative Western blots and analyses of the protein expression of PGC1α, mitochondrial marker (Mito marker), Nrf2, CD36, β-actin and GADPH. <b>B</b>, Representative Western blots and analyses of the protein expression of ACADS, CPT1A, CD36, COXII, (Mito marker). Expression levels were normalized for β actin or GADPH (<b>A</b>, <i>right panel</i>) and mito marker or COXII (<b>B</b>, <i>right panel</i>). The data (± SD, <i>n</i> = 6) is from six independent homogenate or mitochondrial preparations from six different animals from each group. ***<i>P</i> < 0.001, **<i>P</i> < 0.01, *<i>P</i> < 0.05 vs. value obtained for control rats.</p

Effect of temperature on fatty acid metabolism in skeletal muscle mitochondria of untrained and endurance-trained rats - Fig 1

<p><b>The influence of endurance training on mitochondrial oxidation of palmitoylcarnitine (A) and glycerol-3-phosphate (B) at 25</b>°<b>C, 35</b>°<b>C and 42</b>°<b>C.</b> Respiratory rates were measured in mitochondria isolated from control (c) and trained (<b>t</b>) rats in the presence of 150 μM ADP (state 3, phosphorylating respiration) with 0.5 mM palmitoyl-DL-carnitine (<b>A</b>) or 5 mM glycerol-3-phosphate (<b>B</b>). Mean values (± SD) for six mitochondria preparations from six different animals from each group (<i>n</i> = 6) are shown. ^###<i>P</i> < 0.001, ^##<i>P</i> < 0.01, ^#<i>P</i> < 0.05 vs value obtained at 35°C for a given group of animals, i.e., within control rats or trained rats. ***<i>P</i> < 0.001, **<i>P</i> < 0.01, *<i>P</i> < 0.05 vs. value obtained for control rats for a given assay temperature.</p

Respiratory rates and coupling parameters in control and trained rat skeletal muscle mitochondria at 25°C, 35°C and 42°C.

<p>Respiratory rates and coupling parameters in control and trained rat skeletal muscle mitochondria at 25°C, 35°C and 42°C.</p

Values of peak power output, selected cardio-respiratory variables and plasma lactate concentration obtained at exhaustion during the incremental exercise test performed before and after 20 weeks of endurance training.

<p>Values of peak power output, selected cardio-respiratory variables and plasma lactate concentration obtained at exhaustion during the incremental exercise test performed before and after 20 weeks of endurance training.</p

Physical performance (cycling and running) before and after the 20 weeks of cycling endurance training.

<p>Physical performance (cycling and running) before and after the 20 weeks of cycling endurance training.</p

Models fitted to subject 3 data collected during baseline-heavy-intensity exercise transition before training and the corresponding residuals.

<p>The arrow represents the size of the slow component, which is defined as the difference between the value reached at the end of the exercise, and the value of the first (fast) exponential component (represented with the broken line).</p

Oxygen uptake on-kinetics during high-intensity cycling exercise, before and after 20 weeks of training.

<p>Oxygen uptake on-kinetics during high-intensity cycling exercise, before and after 20 weeks of training.</p

Experimental V’O₂ and simulated muscle V’O₂, metabolite concentrations and ATP usage/supply fluxes during low-intensity (baseline) and high-intensity cycling exercise in untrained and trained muscle.

<p>(A) Experimental and simulated V’O₂, simulated ADP and pH. (B) Simulated PCr, P_i and ATP. (C) Simulated ATP usage (UT), ATP supply by OXPHOS (OX), ATP supply by anaerobic glycolysis (GL), ATP supply by creatine kinase (CK). Experimental baseline-heavy-intensity exercise transition: after 3 min. Simulated baseline-heavy-intensity exercise transition: after 3.4 min (the delay by 24 s corresponds to the cardio-dynamic phase of the pulmonary V’O₂ on-kinetics). The muscle V’O₂ is calculated based on the assumption that during baseline-intensity exercise (20 W) muscle V’O₂ constitutes ~75% and during heavy-intensity exercise ~85% of the pulmonary V’O₂ (see Ref. [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0154135#pone.0154135.ref040" target="_blank">40</a>]).</p

Mean (± SD) values of pulmonary oxygen uptake (V’O₂) for 12 subjects during baseline and during heavy-intensity transition.

<p>Note the training-induced attenuation of the slow component of the V’O₂ on-kinetics during high-intensity cycling.</p

Transverse section of human muscle fibers, preserved in epoxy resin.

<p>A representative area of a part of vastus lateralis muscle stained with the mixture of toluidine and methylene blue is showed. The arrows indicate the cross section of capillaries.</p