title: Decrease in oxidative stress and histological changes induced by physical exercise calibrated in rats with osteoarthritis induced by monosodium iodoacetate.
abstract: OBJECTIVE
  The purpose of this study was to evaluate the effects of impact exercise on the joint cartilage of rats with osteoarthritis (OA) induced by monosodium iodoacetate (MIA).
  
  
  METHODS
  Eighteen male rats were divided into three groups of six animals each: control, OA, and OA plus exercise (OAE). The OAE group trained on a treadmill for 8 weeks. Afterward, the right joints of the animals were washed with saline solution and joint lavage was used for biochemical analyses of myeloperoxidase (MPO) and enzyme superoxide dismutase (SOD) activities and total thiol content. The same limb provided samples of the articular capsule for analyses of MPO activity and total thiol content. The left joint was used for histological analysis.
  
  
  RESULTS
  Our results indicate that MPO activity was increased in both OA groups in the lavage as well as the articular capsule, regardless of exercise status. SOD activity was increased in animals with OA, especially in the animals that had run on the treadmill. On the other hand, thiol content in the articular capsule and joint lavage decreased in the OA group, while the OAE group had values similar to those of the control group. The histological data indicate that animals that were submitted to running exercise showed a higher preservation rate of proteoglycan content in the superficial and intermediate areas of the joint cartilage.
  
  
  CONCLUSIONS
  Our results show that physical training contributes to the preservation of joint cartilage in animals with OA and to increase the defense mechanism against oxidative stress.
authors.affiliation: Exercise Biochemistry and Physiology Laboratory, Postgraduate Program in Health Sciences, Health Sciences Unit, Universidade do Extremo Sul Catarinense, Criciúma, SC, Brazil.
authors.forename: D J
authors.initials: DJ
authors.lastname: Cifuentes
authors.forename: L G
authors.initials: LG
authors.lastname: Rocha
authors.forename: L A
authors.initials: LA
authors.lastname: Silva
authors.forename: A C
authors.initials: AC
authors.lastname: Brito
authors.forename: C R
authors.initials: CR
authors.lastname: Rueff-Barroso
authors.forename: L C
authors.initials: LC
authors.lastname: Porto
authors.forename: R A
authors.initials: RA
authors.lastname: Pinho
mesh_terms: D000818:Animals; D002358:Cartilage, Articular / Q000187:drug effects; D004791:Enzyme Inhibitors / Q000009:adverse effects*; D015444:Exercise; D006801:Humans; D007461:Iodoacetates / Q000009:adverse effects*; D007596:Joints; D008297:Male; D010003:Osteoarthritis / Q000139:chemically induced*; D018384:Oxidative Stress / Q000187:drug effects*; D051381:Rats; D017208:Rats, Wistar
chemical_list: D004791:Enzyme Inhibitors; D007461:Iodoacetates