Hibernating brown bears are protected against atherogenic dyslipidemia

• Published in: Scientific Reports
• Main Authors: Giroud, Sylvain, Chery, Isabelle, Arrivé, Mathilde, Prost, Michel, Zumsteg, Julie, Heintz, Dimitri, Evans, Alina L., Gauquelin-Koch, Guillemette, Arnemo, Jon M., Swenson, Jon E., Lefai, Etienne, Bertile, Fabrice, Simon, Chantal, Blanc, Stéphane
• Other Authors: University of Veterinary Medicine Vienna (Vetmeduni), Département Ecologie, Physiologie et Ethologie (DEPE-IPHC), Institut Pluridisciplinaire Hubert Curien (IPHC), Université de Strasbourg (UNISTRA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Institut de biologie moléculaire des plantes (IBMP), Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Recherche Appliquée Spiral Bourgogne (LARA SPIRAL), Inland Norway University of Applied Sciences - Høgskolen i Innlandet, Centre National d'Études Spatiales Toulouse (CNES), Norwegian University of Life Sciences (NMBU), Unité de Nutrition Humaine (UNH), Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Clermont Auvergne (UCA), Département Sciences Analytiques et Interactions Ioniques et Biomoléculaires (DSA-IPHC), Cardiovasculaire, métabolisme, diabétologie et nutrition (CarMeN), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Hospices Civils de Lyon (HCL)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2021
• Subjects: [SDV.BV]Life Sciences [q-bio]/Vegetal Biology; Ursus arctos
• Online Access: https://hal.archives-ouvertes.fr/hal-03360652; https://hal.archives-ouvertes.fr/hal-03360652/document; https://hal.archives-ouvertes.fr/hal-03360652/file/islandora_120670.pdf; https://doi.org/10.1038/s41598-021-98085-7

International audience To investigate mechanisms by which hibernators avoid atherogenic hyperlipidemia during hibernation, we assessed lipoprotein and cholesterol metabolisms of free-ranging Scandinavian brown bears (Ursus arctos). In winter- and summer-captured bears, we measured lipoprotein sizes and sub-classes, triglyceride-related plasma-enzyme activities, and muscle lipid composition along with plasma-levels of antioxidant capacities and inflammatory markers. Although hibernating bears increased nearly all lipid levels, a 36%-higher cholesteryl-ester transfer-protein activity allowed to stabilize lipid composition of high-density lipoproteins (HDL). Levels of inflammatory metabolites, i.e., 7-ketocholesterol and 11ss-prostaglandin F2 alpha, declined in winter and correlated inversely with cardioprotective HDL2b-proportions and HDL-sizes that increased during hibernation. Lower muscle-cholesterol concentrations and lecithin-cholesterol acyltransferase activity in winter suggest that hibernating bears tightly controlled peripheral-cholesterol synthesis and/or release. Finally, greater plasma-antioxidant capacities prevented excessive lipid-specific oxidative damages in plasma and muscles of hibernating bears. Hence, the brown bear manages large lipid fluxes during hibernation, without developing adverse atherogenic effects that occur in humans and non-hibernators.