Undersulfated chondroitin sulfate does not increase in osteoarthritic cartilage.
OBJECTIVE
To test whether there is undersulfation of chondroitin sulfate in osteoarthritic bovine articular cartilage to support the hypothesis that sulfate deficiency is involved with the development of osteoarthritis.


METHODS
Cartilage samples from bovine patellae (n = 32) were divided into 3 groups based on their osteoarthritic progression, as assessed by modified Mankin score. Uronic acid contents of the samples were determined. Fragmentation of the proteoglycans due to proteolytic processing was estimated with agarose gel electrophoresis. The molar ratios of chondroitin sulfate isoforms in the extracted proteoglycans were determined with fluorophore-assisted carbohydrate electrophoresis.


RESULTS
Loss of proteoglycans and accumulation of tissue water was evident in groups II and III, and progressive OA increased heterogeneity of aggrecan population in groups II and III. Importantly, the molar ratio of nonsulfated disaccharide was decreased in the osteoarthritic articular cartilage.


CONCLUSIONS
The structure of chondroitin sulfate in degenerated bovine cartilage did not support the hypothesis that sulfate depletion is present in osteoarthritic joint.
Lammi
Mikko J
MJ
Department of Anatomy, University of Kuopio, 70211 Kuopio, Finland. mikko.lammi@uku.fi
Qu
Cheng-Juan
CJ
Laasanen
Mikko S
MS
Saarakkala
Simo
S
Rieppo
Jarno
J
Jurvelin
Jukka S
JS
Töyräs
Juha
J
D000818:Animals; D015415:Biomarkers / Q000032:analysis; D002358:Cartilage, Articular / Q000473:pathology* / Q000648:ultrastructure*; D002417:Cattle; D002809:Chondroitin Sulfates / Q000032:analysis / Q000378:metabolism*; D004195:Disease Models, Animal; D018450:Disease Progression; D004587:Electrophoresis, Agar Gel; D006025:Glycosaminoglycans / Q000032:analysis / Q000378:metabolism*; D010329:Patella; D012016:Reference Values; D012680:Sensitivity and Specificity; D046509:Tissue Culture Techniques
D015415:Biomarkers; D006025:Glycosaminoglycans; D002809:Chondroitin Sulfates