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Strasbourg, France

Bouitbir J.,CHRU of Strasbourg | Daussin F.,CHRU of Strasbourg | Charles A.-L.,CHRU of Strasbourg | Rasseneur L.,University of Strasbourg | And 5 more authors.
Muscle and Nerve | Year: 2012

Introduction: Statins are associated with adverse skeletal muscle effects. Our objective was to determine if muscular adaptations following exercise training prevented deleterious effects of atorvastatin in glycolytic skeletal muscle. Methods: Twenty rats were divided into 2 groups: a control group (n = 10; Cont) and a 10 days of training group (n = 10; Training). Using the permeabilized fibers technique, we explored mitochondrial function. Results: Exercise training increased V max and H 2O 2 production without altering the free radical leak, and mRNA expression of SOD2 and Cox1 were higher in trained muscle. In the Cont group, atorvastatin exposure increased H 2O 2 production and decreased skeletal muscle V max. The decreased V max effect of atorvastatin was dose dependent. Interestingly, the half-maximal inhibitory concentration (IC 50) was higher in the Training group. H 2O 2 production increased in trained muscle after atorvastatin exposure. Conclusions: These results suggest that improvements in mitochondrial respiratory and antioxidant capacities following endurance training protected mitochondria against statin exposure. © 2012 Wiley Periodicals, Inc.

Charton A.,University of Strasbourg | Peronnet F.,University of Montreal | Doutreleau S.,CHRU of Strasbourg | Doutreleau S.,University of Strasbourg | And 8 more authors.
Drug Design, Development and Therapy | Year: 2014

Background: Oral administration of oxygenated water has been shown to improve blood oxygenation and could be an alternate way for oxygen (O2) supply. In this experiment, tissue oxygenation was compared in anesthetized pigs receiving a placebo or water enriched in O2 by injection or a new electrolytic process. Methods: Forty-two pigs randomized in three groups received either mineral water as placebo or water enriched in O2 by injection or the electrolytic process (10 mL/kg in the stomach). Hemodynamic parameters, partial pressure of oxygen in the arterial blood (PaO2), skin blood flow, and tissue oxygenation (transcutaneous oxygen pressure, or TcPO2) were monitored during 90 minutes of general anesthesia. Absorption and tissue distribution of the three waters administered were assessed using dilution of deuterium oxide. Results: Mean arterial pressure, heart rate, PaO2, arteriovenous oxygen difference, and water absorption from the gut were not significantly different among the three groups. The deuterium to protium ratio was also similar in the plasma, skin, and muscle at the end of the protocol. Skin blood flow decreased in the three groups. TcPO2 slowly decreased over the last 60 minutes of the experiment in the three groups, but when compared to the control group, the values remained significantly higher in animals that received the water enriched in O2 by electrolysis. Conclusions: In this protocol, water enriched in O2 by electrolysis lessened the decline of peripheral tissue oxygenation. This observation is compatible with the claim that the electrolytic process generates water clathrates which trap O2 and facilitate O2 diffusion along pressure gradients. Potential applications of O2-enriched water include an alternate method of oxygen supply. © 2014 Charton et al.

Daussin F.N.,University of Lille Nord de France | Daussin F.N.,University of Montreal | Daussin F.N.,University of Strasbourg | Rasseneur L.,CHRU of Strasbourg | And 13 more authors.
Medicine and Science in Sports and Exercise | Year: 2012

Purpose: The objective of this study was to investigate the time course of the endurance training-induced adaptations in two major mitochondrial functions. Methods: Forty rats were divided into four groups: a control group and three training groups-a 1-d training group, a 5-d training group, and a 10-d training group. The training protocol consisted of 30 min of running on a motorized treadmill (26 mIminj1, 15% grade). Nuclear respiratory factor-1; transcription factor A, mitochondrial; superoxide dismutase-2; glutathione peroxidase-4; and citrate synthase (CS) messenger RNA levels were measured by qPCR. Mitochondrial respiration and H 2O 2 release were assessed using permeabilized fibers of white gastrocnemius in situ. Calculation of free radical leak was performed in two conditions where substrates were identical in both measurements. CS activity was assessed spectrophotometrically. Results: An early time-dependent modulation in messenger RNA levels was observed with training: nuclear respiratory factor-1 and superoxide dismutase- 2 levels increased after acute exercise, transcription factor A, mitochondrial and CS levels improved after 5 d, and glutathione peroxidase- 4 levels increased after 10 d. CS activity improved by 29% ± 8% (P < 0.01) after 5 d together with a 50% ± 7% reduction in the free radical leak (P < 0.05). Finally, 10 d of endurance training did not significantly alter mitochondrial H 2O 2 release but increased mitochondrial respiration rates in situ (P < 0.05). Conclusions: Our results demonstrate that mitochondrial adaptations follow a sequential program in which mitochondrial respiration and free radical leak adaptations occur according to a different timing. Collectively, these results suggest early mitochondrial qualitative adaptations in response to endurance training. Copyright © 2012 by the American College of Sports Medicine.

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