Induction and adaptation of chaperone-assisted selective autophagy CASA in response to resistance exercise in human skeletal muscle

Autophagy. 2015;11(3):538-46. doi: 10.1080/15548627.2015.1017186.


Chaperone-assisted selective autophagy (CASA) is a tension-induced degradation pathway essential for muscle maintenance. Impairment of CASA causes childhood muscle dystrophy and cardiomyopathy. However, the importance of CASA for muscle function in healthy individuals has remained elusive so far. Here we describe the impact of strength training on CASA in a group of healthy and moderately trained men. We show that strenuous resistance exercise causes an acute induction of CASA in affected muscles to degrade mechanically damaged cytoskeleton proteins. Moreover, repeated resistance exercise during 4 wk of training led to an increased expression of CASA components. In human skeletal muscle, CASA apparently acts as a central adaptation mechanism that responds to acute physical exercise and to repeated mechanical stimulation.

Keywords: BAG3; CASA, chaperone-assisted selective autophagy; CK, creatine kinase; HSPB8; TBS, tris-buffered saline; autophagy; chaperone; exercise; human subjects; mechanical tension; muscle; proteostasis; stress.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adaptation, Physiological*
  • Adaptor Proteins, Signal Transducing / metabolism
  • Adult
  • Apoptosis Regulatory Proteins / metabolism
  • Autophagy / physiology*
  • Biopsy
  • Creatine Kinase / metabolism
  • Cytoskeleton / metabolism
  • Filamins / metabolism
  • Humans
  • Male
  • Microfilament Proteins / metabolism
  • Microscopy, Electron
  • Molecular Chaperones / physiology*
  • Muscle Contraction
  • Quadriceps Muscle / pathology
  • Quadriceps Muscle / physiology*
  • Quadriceps Muscle / ultrastructure
  • Young Adult


  • Adaptor Proteins, Signal Transducing
  • Apoptosis Regulatory Proteins
  • BAG3 protein, human
  • FLNC protein, human
  • Filamins
  • Microfilament Proteins
  • Molecular Chaperones
  • SYNPO2 protein, human
  • Creatine Kinase