Limited Oxidative Stress Favors Resistance to Skeletal Muscle Atrophy in Hibernating Brown Bears (Ursus Arctos)

• Published in: Antioxidants
• Main Authors: Chazarin, Blandine, Ziemianin, Anna, Evans, Alina L., Meugnier, Emmanuelle, Loizon, Emmanuelle, Chery, Isabelle, Arnemo, Jon M., Swenson, Jon E., Gauquelin-Koch, Guillemette, Simon, Chantal, Blanc, Stéphane, Lefai, Etienne, Bertile, Fabrice
• Other Authors: Département Sciences Analytiques et Interactions Ioniques et Biomoléculaires (DSA-IPHC), Institut Pluridisciplinaire Hubert Curien (IPHC), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Centre National d'Etudes Spatiales, Department of Forestry and Wildlife Management Inland Norway University of Applied Sciences, Cardiovasculaire, métabolisme, diabétologie et nutrition (CarMeN), Institut National de la Recherche Agronomique (INRA)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Hospices Civils de Lyon (HCL)-Institut National de la Santé et de la Recherche Médicale (INSERM), Département Ecologie, Physiologie et Ethologie (DEPE-IPHC), Department of Wildlife, Fish and Environmental Studies, Swedish University of Agricultural Sciences = Sveriges lantbruksuniversitet (SLU), Faculty of Environmental Sciences and Natural Resource Management, Unité de Nutrition Humaine (UNH), Institut National de la Recherche Agronomique (INRA)-Université Clermont Auvergne 2017-2020 (UCA 2017-2020 ), ANR-16-IDEX-0001,CAP 20-25,CAP 20-25(2016)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2019
• Subjects: brown bears; hibernation; oxidative stress; skeletal muscle; cold response; NRF2; [SDE]Environmental Sciences; Ursus arctos
• Online Access: https://hal.science/hal-02274540; https://hal.science/hal-02274540/document; https://hal.science/hal-02274540/file/antioxidants-08-00334-v2.pdf; https://doi.org/10.3390/antiox8090334

International audience Oxidative stress, which is believed to promote muscle atrophy, has been reported to occurin a few hibernators. However, hibernating bears exhibit ecient energy savings and muscle proteinsparing, despite long-term physical inactivity and fasting. We hypothesized that the regulation ofthe oxidant/antioxidant balance and oxidative stress could favor skeletal muscle maintenance inhibernating brown bears. We showed that increased expressions of cold-inducible proteins CIRBPand RBM3 could favor muscle mass maintenance and alleviate oxidative stress during hibernation.Downregulation of the subunits of the mitochondrial electron transfer chain complexes I, II, and III,and antioxidant enzymes, possibly due to the reduced mitochondrial content, indicated a possiblereduction of the production of reactive oxygen species in the hibernating muscle. Concomitantly, theupregulation of cytosolic antioxidant systems, under the control of the transcription factor NRF2, andthe maintenance of the GSH/GSSG ratio suggested that bear skeletal muscle is not under a significantoxidative insult during hibernation. Accordingly, lower levels of oxidative damage were recorded inhibernating bear skeletal muscles. These results identify mechanisms by which limited oxidativestress may underlie the resistance to skeletal muscle atrophy in hibernatin