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HSP72 Is a Mitochondrial Stress Sensor Critical for Parkin Action, Oxidative Metabolism, and Insulin Sensitivity in Skeletal Muscle

Authors :
Mark A. Febbraio
Teo Soleymani
Jonathan Wanagat
Jamie A. Le
Laurent Vergnes
Zhenqi Zhou
Darren C. Henstridge
Vicente Ribas
Karen Reue
Andrea L. Hevener
Pedram Daraei
Jennifer Phun
Daniel Sitz
Brian G. Drew
Source :
Diabetes
Publication Year :
2014
Publisher :
American Diabetes Association, 2014.

Abstract

Increased heat shock protein (HSP) 72 expression in skeletal muscle prevents obesity and glucose intolerance in mice, although the underlying mechanisms of this observation are largely unresolved. Herein we show that HSP72 is a critical regulator of stress-induced mitochondrial triage signaling since Parkin, an E3 ubiquitin ligase known to regulate mitophagy, was unable to ubiquitinate and control its own protein expression or that of its central target mitofusin (Mfn) in the absence of HSP72. In wild-type cells, we show that HSP72 rapidly translocates to depolarized mitochondria prior to Parkin recruitment and immunoprecipitates with both Parkin and Mfn2 only after specific mitochondrial insult. In HSP72 knockout mice, impaired Parkin action was associated with retention of enlarged, dysmorphic mitochondria and paralleled by reduced muscle respiratory capacity, lipid accumulation, and muscle insulin resistance. Reduced oxygen consumption and impaired insulin action were recapitulated in Parkin-null myotubes, confirming a role for the HSP72-Parkin axis in the regulation of muscle insulin sensitivity. These data suggest that strategies to maintain HSP72 may provide therapeutic benefit to enhance mitochondrial quality and insulin action to ameliorate complications associated with metabolic diseases, including type 2 diabetes.

Details

ISSN :
1939327X and 00121797
Volume :
63
Database :
OpenAIRE
Journal :
Diabetes
Accession number :
edsair.doi.dedup.....429f0649af1d9168004a84c26cfb4972
Full Text :
https://doi.org/10.2337/db13-0665