title: Influence of site and age on biochemical characteristics of the collagen network of equine articular cartilage.
abstract: OBJECTIVE
  To determine variations in biochemical characteristics of equine articular cartilage in relation to age and the degree of predisposition for osteochondral disease at a specific site.
  
  
  METHODS
  Articular cartilage specimens from 53 horses 4 to 30 years old.
  
  
  METHODS
  Healthy specimens were obtained from 2 locations on the proximal articular surface of the first phalanx that had different disease prevalences (site 1 at the mediodorsal margin and site 2 at the center of the medial cavity). Water, total collagen, and hydroxylysine contents and enzymatic (hydroxylysylpyridinoline [HP]) and nonenzymatic (pentosidine) crosslinking were determined at both sites. Differences between sites were analyzed by ANOVA (factors, site, and age), and age correlation was tested by Pearson's product-moment correlation analysis. Significance was set at P< 0.01.
  
  
  RESULTS
  Correlation with age was not found for water, collagen, hydroxylysine contents, and enzymatic cross-linking. Nonenzymatic crosslinking was higher in older horses and was linearly related to age (r = 0.94). Water and collagen contents and HP and pentosidine crosslinks were significantly higher at site 1. Hydroxylysine content was significantly lower at site 1.
  
  
  CONCLUSIONS
  Except for nonenzymatic glycation, the composition of articular cartilage collagen does not change significantly in adult horses. A significant topographic variation exists in biochemical characteristics of the articular cartilage collagen network in equine metacarpophalangeal joints. These differences may influence local biomechanical properties and, hence, susceptibility to osteochondral disease, as will greater pentosidine crosslinks in older horses that are likely to cause stiffer and more brittle cartilage.
authors: Department of General and Large Animal Surgery, Faculty of Veterinary Medicine, Utrecht, The Netherlands.
authors: P A
authors: PA
authors: Brama
authors: J M
authors: JM
authors: TeKoppele
authors: R A
authors: RA
authors: Bank
authors: P R
authors: PR
authors: van Weeren
authors: A
authors: A
authors: Barneveld
mesh_terms: D000375:Aging / Q000378:metabolism*; D000818:Animals; D002358:Cartilage, Articular / Q000378:metabolism*; D003094:Collagen / Q000378:metabolism*; D006734:Horse Diseases / Q000473:pathology; D006736:Horses / Q000033:anatomy & histology / Q000378:metabolism*; D010007:Osteochondritis / Q000473:pathology / Q000662:veterinary; D011499:Protein Processing, Post-Translational
chemical_list: D003094:Collagen