Protective effect of the chondroprotective agent Cosequin DS on bovine articular cartilage exposed in vitro to nonsteroidal antiinflammatory agents.

: Studies were conducted to test the hypothesis that exposure of articular cartilage to a combination of the "chondroprotective" agents glucosamine hydrochloride, low-molecular-weight chondroitin sulfate, and manganese ascorbate (Cosequin DS [CDS], Nutramax Laboratories, Inc.) prevents the potentially adverse effects of NSAIDs on cartilage. Articular cartilage proteoglycan synthesis and degradation were used to monitor in vitro cartilage activity following timed exposure to levels of NSAIDs routinely applied in veterinary medicine. Etodolac exposure for 144 hours induced significant inhibition of cartilage matrix synthesis and increased the rate of matrix breakdown. Addition of CDS reversed both activities. Cartilage metabolism was not affected by exposure to indomethacin and remained responsive to CDS with an increase in synthetic activity. Aspirin significantly stimulated chondrocyte synthetic activity in the presence and absence of CDS. Carprofen at therapeutic levels had a mild (15%) stimulatory effect on cartilage metabolism and reduced matrix breakdown. Addition of CDS significantly accelerated (30%) matrix synthesis. At higher levels carprofen was toxic, reducing cell activity by 80%. The data suggest that CDS may be a useful adjunct therapy for preservation of articular cartilage by reversing the adverse metabolic effects of etodolac and providing accelerated cartilage synthetic activity in the presence of therapeutic levels of carprofen.