31
views
0
recommends
+1 Recommend
0 collections
    0
    shares
      • Record: found
      • Abstract: found
      • Article: found
      Is Open Access

      Membrane Phospholipid Fatty Acid Composition Regulates Cardiac SERCA Activity in a Hibernator, the Syrian Hamster ( Mesocricetus auratus)

      research-article

      Read this article at

      Bookmark
          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

          Abstract

          Polyunsaturated fatty acids (PUFA) have strong effects on hibernation and daily torpor. Increased dietary uptake of PUFA of the n-6 class, particularly of Linoleic acid (LA, C18:2 n-6) lengthens torpor bout duration and enables animals to reach lower body temperatures (T b) and metabolic rates. As previously hypothesized, this well-known influence of PUFA may be mediated via effects of the membrane fatty acid composition on sarcoplasmic reticulum (SR) Ca 2+−ATPase 2a (SERCA) in the heart of hibernators. We tested the hypotheses that high proportions of n-6 PUFA in general, or specifically high proportions of LA (C18:2 n-6) in SR phospholipids (PL) should be associated with increased cardiac SERCA activity, and should allow animals to reach lower minimum T b in torpor. We measured activity of SERCA from hearts of hibernating and non-hibernating Syrian hamsters ( Mesocricetus auratus) in vitro at 35°C. Further, we determined the PL fatty acid composition of the SR membrane of these hearts. We found that SERCA activity strongly increased as the proportion of LA in SR PL increased but was negatively affected by the content of Docosahexaenoic acid (DHA; C22:6 n-3). SR PL from hibernating hamsters were characterized by high proportions of LA and low proportions of DHA. As a result, SERCA activity was significantly higher during entrance into torpor and in torpor compared to inter-bout arousal. Also, animals with increased SERCA activity reached lower T b during torpor. Interestingly, a subgroup of hamsters which never entered torpor but remained euthermic throughout winter displayed a phenotype similar to animals in summer. This was characterized by lower proportions of LA and increased proportions of DHA in SR membranes, which is apparently incompatible with torpor. We conclude that the PUFA composition of SR membranes affects cardiac function via modulating SERCA activity, and hence determines the minimum T b tolerated by hibernators.

          Related collections

          Author and article information

          Contributors
          Role: Editor
          Journal
          PLoS One
          PLoS ONE
          plos
          plosone
          PLoS ONE
          Public Library of Science (San Francisco, USA )
          1932-6203
          2013
          1 May 2013
          : 8
          : 5
          : e63111
          Affiliations
          [1 ]Research Institute of Wildlife Ecology, Department of Integrative Biology and Evolution, University of Veterinary Medicine, Vienna, Austria
          [2 ]University Medical Center Groningen, Departments of Chronobiology & Molecular Neurobiology, University of Groningen, Groningen, The Netherlands
          [3 ]Department of Chronobiology, University of Groningen, Groningen, The Netherlands
          [4 ]Wildlife Management, University of Applied Sciences Van Hall Larenstein, Leeuwarden, The Netherlands
          [5 ]University Medical Center Groningen, Nuclear Medicine and Molecular Imaging, University of Groningen, Groningen, The Netherlands
          Max Delbrueck Center for Molecular Medicine, Germany
          Author notes

          Competing Interests: The authors have declared that no competing interests exist.

          Provided the tissues: AS AB. Conceived and designed the experiments: WA TR. Performed the experiments: SG CF. Analyzed the data: SG CF TR. Wrote the paper: SG.

          [¤]

          Current address: Institute of Arctic Biology, University of Alaska Fairbanks, Fairbanks, Alaska, United States of America

          Article
          PONE-D-12-38460
          10.1371/journal.pone.0063111
          3641109
          23650545
          fc85fc3e-d458-4ca4-afbb-3550199726ee
          Copyright @ 2013

          This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

          History
          : 7 December 2012
          : 28 March 2013
          Page count
          Pages: 9
          Funding
          SG and this research work were financially supported by a postdoctoral fellowship of the University of Veterinary Medicine Vienna (Austria). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
          Categories
          Research Article
          Biology
          Biochemistry
          Lipids
          Fatty Acids
          Proteins
          Transmembrane Transport Proteins
          Cryobiology
          Ecology
          Ecophysiology
          Model Organisms
          Animal Models
          Zoology
          Animal Physiology
          Medicine
          Cardiovascular
          Arrhythmias
          Heart Failure

          Uncategorized
          Uncategorized

          Comments

          Comment on this article