title: Cytokine and Antioxidant Regulation in the Intestine of the Gray Mouse Lemur (Microcebus murinus) During Torpor.
abstract: During food shortages, the gray mouse lemur (Microcebus murinus) of Madagascar experiences daily torpor thereby reducing energy expenditures. The present study aimed to understand the impacts of torpor on the immune system and antioxidant response in the gut of these animals. This interaction may be of critical importance given the trade-off between the energetically costly immune response and the need to defend against pathogen entry during hypometabolism. The protein levels of cytokines and antioxidants were measured in the small intestine (duodenum, jejunum, and ileum) and large intestine of aroused and torpid lemurs. While there was a significant decrease of some pro-inflammatory cytokines (IL-6 and TNF-α) in the duodenum and jejunum during torpor as compared to aroused animals, there was no change in anti-inflammatory cytokines. We observed decreased levels of cytokines (IL-12p70 and M-CSF), and several chemokines (MCP-1 and MIP-2) but an increase in MIP-1α in the jejunum of the torpid animals. In addition, we evaluated antioxidant response by examining the protein levels of antioxidant enzymes and total antioxidant capacity provided by metabolites such as glutathione (and others). Our results indicated that levels of antioxidant enzymes did not change between torpor and aroused states, although antioxidant capacity was significantly higher in the ileum during torpor. These data suggest a suppression of the immune response, likely as an energy conservation measure, and a limited role of antioxidant defenses in supporting torpor in lemur intestine.
authors.affiliation: Institute of Biochemistry & Department of Biology, Carleton University, Ottawa, ON K1S 5B6, Canada; Department of Surgery & Center for Engineering in Medicine, Massachusetts General Hospital & Harvard Medical School, Charlestown, MA 02129, USA.
authors.forename: Shannon N
authors.initials: SN
authors.lastname: Tessier
authors.affiliation: Institute of Biochemistry & Department of Biology, Carleton University, Ottawa, ON K1S 5B6, Canada; Department of Biology, University of Waterloo, Waterloo, ON N2L 3G1, Canada.
authors.forename: Barbara A
authors.initials: BA
authors.lastname: Katzenback
authors.affiliation: UMR 7179 Centre National de la Recherche Scientifique, Muséum National d'Histoire Naturelle, Brunoy 91800, France.
authors.forename: Fabien
authors.initials: F
authors.lastname: Pifferi
authors.affiliation: UMR 7179 Centre National de la Recherche Scientifique, Muséum National d'Histoire Naturelle, Brunoy 91800, France.
authors.forename: Martine
authors.initials: M
authors.lastname: Perret
authors.affiliation: Institute of Biochemistry & Department of Biology, Carleton University, Ottawa, ON K1S 5B6, Canada. Electronic address: kenneth_storey@carleton.ca.
authors.forename: Kenneth B
authors.initials: KB
authors.lastname: Storey
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000378:metabolism*; D016565:Cheirogaleidae / Q000378:metabolism*; D018925:Chemokines / Q000378:metabolism; D016207:Cytokines / Q000378:metabolism*; D004734:Energy Metabolism; D005260:Female; D007413:Intestinal Mucosa / Q000378:metabolism*; D018384:Oxidative Stress; D010088:Oxidoreductases / Q000378:metabolism; D064348:Torpor
chemical_list: D000975:Antioxidants; D018925:Chemokines; D016207:Cytokines; D010088:Oxidoreductases
keywords: Antioxidant enzymes; Chemokines; Cytokines; Gut immunology; Primate torpor