title: Direct and indirect markers of cartilage metabolism in synovial fluid obtained from dogs with hip dysplasia and correlation with clinical and radiographic variables.
abstract: OBJECTIVE
  To compare activities of interleukin (IL)-1beta, IL-6, tumor necrosis factor (TNF)-alpha, and matrix metalloproteinase (MMP)-3 and contents of sulfated glycosaminoglycan (S-GAG) in joint fluid obtained from dogs with hip dysplasia (HD) and clinically normal dogs, evaluate correlations among these markers in joint fluid obtained from dogs with HD, and evaluate correlations between each marker and clinical and radiographic variables. Animals-26 dogs with HD (clinical group) and 43 clinically normal Beagles (control group).
  
  
  METHODS
  Joint fluid was aseptically collected from the hip joints of all dogs. For each dog in the clinical group, age, duration of lameness, radiographic osteoarthritis (OA) score, and Norberg angle in each affected joint were recorded. Activities of IL-1beta, IL-6, TNF-alpha, and MMP-3 and S-GAG contents were measured. Values were compared between groups by use of Mann-Whitney U tests, and the Spearman rank correlation test was used to evaluate correlations among markers and between each marker and clinical or radiographic variables.
  
  
  RESULTS
  Values of all markers were significantly higher for the clinical group, compared with values for the control group. There was a moderate positive correlation between lameness duration and IL-6 activity and a strong negative correlation between the Norberg angle and IL-1beta activity.
  
  
  CONCLUSIONS
  Analysis of our results indicated that there was a significant increase in markers of OA in dogs with HD. Activities of IL-1beta and IL-6 in joint fluid of dogs with HD may be influenced by the severity of laxity in the hip joint and lameness duration, respectively.
authors.affiliation: Division of Veterinary Surgery, Department of Veterinary Science, Faculty of Veterinary Medicine, Nippon Veterinary and Animal Science University, 1-7-1 Kyonan-cho, Musashino-shi, Tokyo 180-8602, Japan.
authors.forename: Yukihiro
authors.initials: Y
authors.lastname: Fujita
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Hara
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Nezu
authors.forename: Shinya
authors.initials: S
authors.lastname: Yamaguchi
authors.forename: Kurt S
authors.initials: KS
authors.lastname: Schulz
authors.forename: Masahiro
authors.initials: M
authors.lastname: Tagawa
mesh_terms: D000367:Age Factors; D000818:Animals; D001681:Biological Assay / Q000662:veterinary; D015415:Biomarkers / Q000378:metabolism; D002356:Cartilage / Q000378:metabolism*; D045744:Cell Line, Tumor; D004285:Dogs; D006025:Glycosaminoglycans / Q000378:metabolism; D006619:Hip Dysplasia, Canine / Q000000981:diagnostic imaging / Q000378:metabolism* / Q000473:pathology; D006801:Humans; D007375:Interleukin-1 / Q000378:metabolism; D015850:Interleukin-6 / Q000378:metabolism; D019278:Matrix Metalloproteinase 3 / Q000378:metabolism; D051379:Mice; D011859:Radiography; D018709:Statistics, Nonparametric; D013582:Synovial Fluid / Q000378:metabolism*; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
chemical_list: D015415:Biomarkers; D006025:Glycosaminoglycans; D007375:Interleukin-1; D015850:Interleukin-6; D014409:Tumor Necrosis Factor-alpha; C013786:A73025; D019278:Matrix Metalloproteinase 3