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Giroud S, Perret M, Stein P, Goudable J, Aujard F, Gilbert C, Robin JP, Le Maho Y, Zahariev A, Blanc S, Momken I. The grey mouse lemur uses season-dependent fat or protein sparing strategies to face chronic food restriction. PLoS One 2010; 5:e8823. [PMID: 20098678 PMCID: PMC2809095 DOI: 10.1371/journal.pone.0008823] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2009] [Accepted: 12/30/2009] [Indexed: 11/18/2022] Open
Abstract
During moderate calorie restriction (CR) the heterotherm Microcebus murinus is able to maintain a stable energy balance whatever the season, even if only wintering animals enter into torpor. To understand its energy saving strategies to respond to food shortages, we assessed protein and energy metabolisms associated with wintering torpor expression or summering torpor avoidance. We investigated body composition, whole body protein turnover, and daily energy expenditure (DEE), during a graded (40 and 80%) 35-day CR in short-days (winter; SD40 and SD80, respectively) and long-days (summer; LD40 and LD80, respectively) acclimated animals. LD40 animals showed no change in fat mass (FM) but a 12% fat free mass (FFM) reduction. Protein balance being positive after CR, the FFM loss was early and rapid. The 25% DEE reduction, in LD40 group was mainly explained by FFM changes. LD80 animals showed a steady body mass loss and were excluded from the CR trial at day 22, reaching a survival-threatened body mass. No data were available for this group. SD40 animals significantly decreased their FM level by 21%, but maintained FFM. Protein sparing was achieved through a 35 and 39% decrease in protein synthesis and catabolism (protein turnover), respectively, overall maintaining nitrogen balance. The 21% reduction in energy requirement was explained by the 30% nitrogen flux drop but also by torpor as DEE FFM-adjusted remained 13% lower compared to ad-libitum. SD80 animals were unable to maintain energy and nitrogen balances, losing both FM and FFM. Thus summering mouse lemurs equilibrate energy balance by a rapid loss of active metabolic mass without using torpor, whereas wintering animals spare protein and energy through increased torpor expression. Both strategies have direct fitness implication: 1) to maintain activities at a lower body size during the mating season and 2) to preserve an optimal wintering muscle mass and function.
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Affiliation(s)
- Sylvain Giroud
- Unité Mixte de Recherche 7178, Département d'Ecologie Physiologie Ethologie, Institut Pluridisciplinaire Hubert Curien, Centre National de la Recherche Scientifique, Université de Strasbourg, Strasbourg, France
- Mécanismes Adaptatifs et Evolution, Unité Mixte de Recherche 7179, Centre National de la Recherche Scientifique, Muséum National d'Histoire Naturelle, Brunoy, France
| | - Martine Perret
- Mécanismes Adaptatifs et Evolution, Unité Mixte de Recherche 7179, Centre National de la Recherche Scientifique, Muséum National d'Histoire Naturelle, Brunoy, France
| | - Peter Stein
- Department of Surgery, University of Medicine and Dentistry of New Jersey, Stratford, New Jersey, United States of America
| | - Joëlle Goudable
- Institut des Sciences Pharmaceutiques et Biologiques, Faculté de Pharmacie, Lyon 1, Fédération de Biochimie, Hôpital Edouard Herriot, Lyon, France
| | - Fabienne Aujard
- Mécanismes Adaptatifs et Evolution, Unité Mixte de Recherche 7179, Centre National de la Recherche Scientifique, Muséum National d'Histoire Naturelle, Brunoy, France
| | - Caroline Gilbert
- Unité Mixte de Recherche 7178, Département d'Ecologie Physiologie Ethologie, Institut Pluridisciplinaire Hubert Curien, Centre National de la Recherche Scientifique, Université de Strasbourg, Strasbourg, France
- Université Henri Poincaré, Nancy Université, Vandoeuvre-Les-Nancy, France
| | - Jean Patrice Robin
- Unité Mixte de Recherche 7178, Département d'Ecologie Physiologie Ethologie, Institut Pluridisciplinaire Hubert Curien, Centre National de la Recherche Scientifique, Université de Strasbourg, Strasbourg, France
| | - Yvon Le Maho
- Unité Mixte de Recherche 7178, Département d'Ecologie Physiologie Ethologie, Institut Pluridisciplinaire Hubert Curien, Centre National de la Recherche Scientifique, Université de Strasbourg, Strasbourg, France
| | - Alexandre Zahariev
- Unité Mixte de Recherche 7178, Département d'Ecologie Physiologie Ethologie, Institut Pluridisciplinaire Hubert Curien, Centre National de la Recherche Scientifique, Université de Strasbourg, Strasbourg, France
| | - Stéphane Blanc
- Unité Mixte de Recherche 7178, Département d'Ecologie Physiologie Ethologie, Institut Pluridisciplinaire Hubert Curien, Centre National de la Recherche Scientifique, Université de Strasbourg, Strasbourg, France
- * E-mail:
| | - Iman Momken
- Unité Mixte de Recherche 7178, Département d'Ecologie Physiologie Ethologie, Institut Pluridisciplinaire Hubert Curien, Centre National de la Recherche Scientifique, Université de Strasbourg, Strasbourg, France
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