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Genetic manipulation of cardiac Hsp72 levels does not alter substrate metabolism but reveals insights into high-fat feeding-induced cardiac insulin resistance

Citation

Henstridge, DC and Estevez, E and Allen, TL and Heywood, SE and Gardner, T and Yang, C and Mellett, NA and Kingwell, BA and Meikle, PJ and Febbraio, MA, Genetic manipulation of cardiac Hsp72 levels does not alter substrate metabolism but reveals insights into high-fat feeding-induced cardiac insulin resistance, Cell Stress and Chaperones, 20, (3) pp. 461-472. ISSN 1355-8145 (2015) [Refereed Article]

Copyright Statement

Copyright 2015 Cell Stress Society International

DOI: doi:10.1007/s12192-015-0571-6

Abstract

Heat shock protein 72 (Hsp72) protects cells against a variety of stressors, and multiple studies have suggested that Hsp72 plays a cardioprotective role. As skeletal muscle Hsp72 overexpression can protect against high-fat diet (HFD)-induced insulin resistance, alterations in substrate metabolism may be a mechanism by which Hsp72 is cardioprotective. We investigated the impact of transgenically overexpressing (Hsp72 Tg) or deleting Hsp72 (Hsp72 KO) on various aspects of cardiac metabolism. Mice were fed a normal chow (NC) or HFD for 12 weeks from 8 weeks of age to examine the impact of diet-induced obesity on metabolic parameters in the heart. The HFD resulted in an increase in cardiac fatty acid oxidation and a decrease in cardiac glucose oxidation and insulin-stimulated cardiac glucose clearance; however, there was no difference in Hsp72 Tg or Hsp72 KO mice in these rates compared with their respective wild-type control mice. Although HFD-induced cardiac insulin resistance was not rescued in the Hsp72 Tg mice, it was preserved in the skeletal muscle, suggesting tissue-specific effects of Hsp72 overexpression on substrate metabolism. Comparison of two different strains of mice (BALB/c vs. C57BL/6J) also identified strain-specific differences in regard to HFD-induced cardiac lipid accumulation and insulin resistance. These strain differences suggest that cardiac lipid accumulation can be dissociated from cardiac insulin resistance. Our study finds that genetic manipulation of Hsp72 does not lead to alterations in metabolic processes in cardiac tissue under resting conditions, but identifies mouse strain-specific differences in cardiac lipid accumulation and insulin-stimulated glucose clearance.

Item Details

Item Type:Refereed Article
Keywords:cardiac insulin resistance, glucose metabolism, heart, Hsp72, lipid, glucose, heat shock protein 72, palmitic acid, adverse effects, animal, Bagg albino mouse, body composition, C57BL mouse, feeding behavior, genetics, heart diseases, knockout mouse
Research Division:Biological Sciences
Research Group:Biochemistry and cell biology
Research Field:Cell metabolism
Objective Division:Health
Objective Group:Clinical health
Objective Field:Clinical health not elsewhere classified
UTAS Author:Henstridge, DC (Mr Darren Henstridge)
ID Code:133353
Year Published:2015
Web of Science® Times Cited:8
Deposited By:Health Sciences
Deposited On:2019-06-24
Last Modified:2019-07-22
Downloads:0

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