title: Strenuous running exacerbates knee cartilage erosion induced by low amount of mono-iodoacetate in rats.
abstract: It is still debated whether strenuous running in the inflammatory phase produces beneficial or harmful effect in rat knees. We examined (1) the dropout rate of rats during a 30-km running protocol, (2) influences of strenuous running and/or low amounts of mono-iodoacetate injection on cartilage, and (3) the effect of strenuous running on synovitis.
  
  
  
  Rats were forced to run 30 km over 6 weeks and the dropout rate was examined. One week after 0.1 mg mono-iodoacetate was injected into the right knee, rats were forced to run either 15 km or not run at all over 3 weeks, after which knee cartilage was evaluated. Synovium at the infrapatellar fat pad was also examined histologically.
  
  
  
  Even though all 12 rats run up to 15 km, only 6 rats completed 30 km of running. Macroscopically, 0.1 mg mono-iodoacetate induced erosion at the tibial cartilage irrespective of 15 km of running. Histologically, 0.1 mg mono-iodoacetate induced loss of cartilage matrix in the tibial cartilage, and an additional 15 km of strenuous running significantly exacerbated the loss. Synovitis caused by mono-iodoacetate improved after running.
  
  
  
  Only 50% of rats completed 30 km of running because of foot problems. Strenuous running further exacerbated tibial cartilage erosion but did not influence synovitis induced by mono-iodoacetate.
authors.affiliation: Department of Joint Surgery and Sports Medicine, Graduate School of Medicine, Tokyo Medical and Dental University, Tokyo, Japan.
authors.forename: Ryusuke
authors.initials: R
authors.lastname: Saito
authors.affiliation: Department of Joint Surgery and Sports Medicine, Graduate School of Medicine, Tokyo Medical and Dental University, Tokyo, Japan.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Muneta
authors.affiliation: Center for Stem Cell and Regenerative Medicine, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8510, Japan.
authors.forename: Nobutake
authors.initials: N
authors.lastname: Ozeki
authors.affiliation: Department of Joint Surgery and Sports Medicine, Graduate School of Medicine, Tokyo Medical and Dental University, Tokyo, Japan.|Center for Stem Cell and Regenerative Medicine, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8510, Japan.
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Nakagawa
authors.affiliation: Department of Joint Surgery and Sports Medicine, Graduate School of Medicine, Tokyo Medical and Dental University, Tokyo, Japan.
authors.forename: Mio
authors.initials: M
authors.lastname: Udo
authors.affiliation: Department of Joint Surgery and Sports Medicine, Graduate School of Medicine, Tokyo Medical and Dental University, Tokyo, Japan.
authors.forename: Katsuaki
authors.initials: K
authors.lastname: Yanagisawa
authors.affiliation: Department of Cartilage Regeneration, Graduate School of Medicine, Tokyo Medical and Dental University, Tokyo, Japan.
authors.forename: Kunikazu
authors.initials: K
authors.lastname: Tsuji
authors.affiliation: Clinical Research Center, Tokyo Medical and Dental University, Tokyo, Japan.
authors.forename: Makoto
authors.initials: M
authors.lastname: Tomita
authors.affiliation: Department of Joint Surgery and Sports Medicine, Graduate School of Medicine, Tokyo Medical and Dental University, Tokyo, Japan.
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Koga
authors.affiliation: Center for Stem Cell and Regenerative Medicine, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8510, Japan. sekiya.arm@tmd.ac.jp.
authors.forename: Ichiro
authors.initials: I
authors.lastname: Sekiya
mesh_terms: D000818:Animals; D002358:Cartilage, Articular / Q000187:drug effects / Q000473:pathology*; D007270:Injections, Intra-Articular; D007461:Iodoacetates / Q000008:administration & dosage / Q000633:toxicity*; D007719:Knee Joint / Q000187:drug effects / Q000473:pathology*; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D012420:Running / Q000639:trends*; D013314:Stress, Mechanical
chemical_list: D007461:Iodoacetates
keywords: Cartilage; Mono-iodoacetate (MIA); Osteoarthritis; Rat; Strenuous running; Synovitis