title: Effects of long-term resistance exercise training on autophagy in rat skeletal muscle of chloroquine-induced sporadic inclusion body myositis.
abstract: OBJECTIVE
  We examined whether resistance exercise training restores impaired autophagy functions caused by Chloroquine (CQ)-induced Sporadic Inclusion Body Myositis (sIBM) in rat skeletal muscle.
  
  
  METHODS
  Male wistar rats were randomly assigned into three groups: Sham (n = 6), CQ (n = 6), and CQ + Exercise (CE, n = 6). To create a rat model of sIBM, rats in the CQ and CE group were intraperitoneally injected with CQ 5 days a week for 16 weeks. Rats in the CE group performed resistance exercise training 3 times a week for 8 weeks in conjunction with CQ starting from week 9 to week 16. During the training period, maximal carrying load, body weight, muscle weight, and relative muscle weight were measured. Autophagy responses were examined by measuring specific markers.
  
  
  RESULTS
  While maximal carrying capacity for resistance exercise training was dramatically increased in the CE group, no significant changes occurred in the skeletal muscle weight as well as in the relative muscle weight of CE compared to the other groups. CQ treatment caused significant increases in the levels of Beclin-1 and p62, and decreases in the levels of LAMP-2 proteins. Interestingly, no significant differences in the LC3-II/I ratio or the LC3-II protein levels were observed. Although CQ-treatment groups suppressed the levels of the potent autophagy inducer, BNIP3, p62 levels were decreased in only the CE group.
  
  
  CONCLUSIONS
  Our findings demonstrate that sIBM induced by CQ treatment results in muscle degeneration via impaired autophagy and that resistance exercise training improves movable loading activity. Finally, regular exercise training may provide protection against sIBM by enhancing the autophagy flux through p62 protein.
authors.affiliation: Department of Exercise Science and Community Health, University of West Florida, Pensacola, USA.
authors.forename: Insu
authors.initials: I
authors.lastname: Kwon
authors.affiliation: Department of Exercise Science and Community Health, University of West Florida, Pensacola, USA.
authors.forename: Youngil
authors.initials: Y
authors.lastname: Lee
authors.affiliation: Department of Exercise Science and Community Health, University of West Florida, Pensacola, USA.
authors.forename: Ludmila M
authors.initials: LM
authors.lastname: Cosio-Lima
authors.affiliation: Exercise Biochemistry Laboratory, Korea National Sport University, Seoul, Republic of Korea.
authors.forename: Joon-Yong
authors.initials: JY
authors.lastname: Cho
authors.affiliation: Department of Physical Education, Korea National Sport University, Seoul, Republic of Korea.
authors.forename: Dong-Chul
authors.initials: DC
authors.lastname: Yeom
keywords: Resistance exercise; autophagy; chloroquine; sIBM; skeletal muscles