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Journal articles
Threshold effect in the H2O2 production of skeletal muscle mitochondria during fasting and refeeding
Abstract : Under nutritional deprivation, the energetic benefits of reducing mitochondrial metabolism are often associated with enhanced harmful pro-oxidant effects and a subsequent long-term negative impact on cellular integrity. However, the flexibility of mitochondrial functioning under stress has rarely been explored during the transition from basal non-phosphorylating to maximal phosphorylating oxygen consumption. Here, we experimentally tested whether ducklings (Cairina moscnata), fasted for 6 days and subsequently refed for 3 days, exhibited modifications to their mitochondrial fluxes, i.e. oxygen consumption, ATP synthesis, reactive oxygen species generation (ROS) and associated ratios, such as the electron leak (% ROS/O) and the oxidative cost of ATP production (% ROS/ATP). This was carried out at different steady-state rates of oxidative phosphorylation in both pectoralis (glycolytic) and gastrocnemius (oxidative) muscles. Fasting induced a decrease in the rates of oxidative phosphorylation and maximal ROS release. These changes were completely reversed by 3 days of refeeding. Yet, the fundamental finding of the present study was the existence of a clear threshold in ROS release and associated ratios, which remained low until a low level of mitochondrial activity was reached (30-40% of maximal oxidative phosphorylation activity).
https://hal-univ-lyon1.archives-ouvertes.fr/hal-02067274
Contributor : Nathalie Lyvet Connect in order to contact the contributor
Submitted on : Friday, June 4, 2021 - 1:33:31 PM
Last modification on : Tuesday, January 4, 2022 - 6:14:55 AM
Long-term archiving on: : Sunday, September 5, 2021 - 7:21:57 PM
Contributor : Nathalie Lyvet Connect in order to contact the contributor
Submitted on : Friday, June 4, 2021 - 1:33:31 PM
Last modification on : Tuesday, January 4, 2022 - 6:14:55 AM
Long-term archiving on: : Sunday, September 5, 2021 - 7:21:57 PM
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