Publication Details

Category Text Publication
Reference Category Journals
DOI 10.1074/jbc.M116.742916
Title (Primary) Biochemical foundations of health and energy conservation in hibernating free-ranging subadult brown bear Ursus arctos
Author Gjesing Welinder, K.; Hansen, R.; Toft Overgaard, M.; Brohus, M.; Sønderkær, M.; von Bergen, M.; Rolle-Kampczyk, U.; Otto, W.; Lindahl, T.L.; Arinell, K.; Evans, A.L.; Swenson, J.E.; Revsbech, I.G.; Frøbert, O.
Source Titel Journal of Biological Chemistry
Year 2016
Department MOLSYB
Volume 291
Page From 22509
Page To 22523
Language englisch
Keywords Antimicrobial proteins; blood constituents; coagulation factors; complement system; hibernation biochemistry; metabolomics; protein turnover; proteomics; sex hormone binding globulin SHBG
UFZ wide themes RU3;
Abstract Brown bears (Ursus arctos) hibernate for 5–7 months without eating, drinking, urinating, and defecating at a metabolic rate of only 25% of the summer activity rate. Nonetheless, they emerge healthy and alert in spring. We quantified the biochemical adaptations for hibernation by comparing the proteome, metabolome, and hematological features of blood from hibernating and active free-ranging subadult brown bears with a focus on conservation of health and energy. We found that total plasma protein concentration increased during hibernation, even though the concentrations of most individual plasma proteins decreased, as did the white blood cell types. Strikingly, antimicrobial defense proteins increased in concentration. Central functions in hibernation involving the coagulation response and protease inhibition, as well as lipid transport and metabolism, were upheld by increased levels of very few key or broad specificity proteins. The changes in coagulation factor levels matched the changes in activity measurements. A dramatic 45-fold increase in sex hormone-binding globulin levels during hibernation draws, for the first time, attention to its significant but unknown role in maintaining hibernation physiology. We propose that energy for the costly protein synthesis is reduced by three mechanisms as follows: (i) dehydration, which increases protein concentration without de novo synthesis; (ii) reduced protein degradation rates due to a 6 °C reduction in body temperature and decreased protease activity; and (iii) a marked redistribution of energy resources only increasing de novo synthesis of a few key proteins. The comprehensive global data identified novel biochemical strategies for bear adaptations to the extreme condition of hibernation and have implications for our understanding of physiology in general.
Persistent UFZ Identifier
Gjesing Welinder, K., Hansen, R., Toft Overgaard, M., Brohus, M., Sønderkær, M., von Bergen, M., Rolle-Kampczyk, U., Otto, W., Lindahl, T.L., Arinell, K., Evans, A.L., Swenson, J.E., Revsbech, I.G., Frøbert, O. (2016):
Biochemical foundations of health and energy conservation in hibernating free-ranging subadult brown bear Ursus arctos
J. Biol. Chem. 291 , 22509 - 22523 10.1074/jbc.M116.742916