Cholesterol and lipoprotein dynamics in a hibernating mammal. PLoS One 2011;6(12):e29111
Date
12/24/2011Pubmed ID
22195001Pubmed Central ID
PMC3240636DOI
10.1371/journal.pone.0029111Scopus ID
2-s2.0-83455168928 (requires institutional sign-in at Scopus site) 33 CitationsAbstract
Hibernating mammals cease feeding during the winter and rely primarily on stored lipids to fuel alternating periods of torpor and arousal. How hibernators manage large fluxes of lipids and sterols over the annual hibernation cycle is poorly understood. The aim of this study was to investigate lipid and cholesterol transport and storage in ground squirrels studied in spring, summer, and several hibernation states. Cholesterol levels in total plasma, HDL and LDL particles were elevated in hibernators compared with spring or summer squirrels. Hibernation increased plasma apolipoprotein A-I expression and HDL particle size. Expression of cholesterol 7 alpha-hydroxylase was 13-fold lower in hibernators than in active season squirrels. Plasma triglycerides were reduced by fasting in spring but not summer squirrels. In hibernators plasma β-hydroxybutyrate was elevated during torpor whereas triglycerides were low relative to normothermic states. We conclude that the switch to a lipid-based metabolism during winter, coupled with reduced capacity to excrete cholesterol creates a closed system in which efficient use of lipoproteins is essential for survival.
Author List
Otis JP, Sahoo D, Drover VA, Yen CL, Carey HVAuthor
Daisy Sahoo PhD Dean, Professor in the Medicine department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
3-Hydroxybutyric AcidAcyltransferases
Animals
Aryl Hydrocarbon Hydroxylases
Bile
Body Temperature
Cholesterol
Fatty Acids
Female
Gene Expression Regulation
Hibernation
Hydroxymethylglutaryl CoA Reductases
Lipoproteins
Male
Models, Biological
Organ Specificity
Sciuridae
Seasons
Steroid Hydroxylases
Triglycerides
