In vivo chondroprotection and metabolic synergy of glucosamine and chondroitin sulfate

Supplements of glucosamine hydrochloride, low molecular weight chondroitin sulfate, and manganese ascorbate were tested separately and in combination for their ability to retard progression of cartilage degeneration in a rabb it instability model of osteoarthrosis. Computerized quantitative histologi c evaluation of safranin O stained sections of the medial femoral condyles measured the grade and extent of tissue involvement of lesions. Severe lesi ons (Mankin grade greater than 7) were absent in all animals supplemented w ith a dietary mixture of glucosamine, chondroitin sulfate, and manganese as corbate, Total linear involvement (mm of lesioned surface) and total grade (mean grade x number of lesions per animal) were reduced significantly in a nimals given the combination compared with controls (59% and 74% respective ly), Animals supplemented with glucosamine, chondroitin sulfate, or mangane se ascorbate alone had less moderate and severe tissue involvement than con trols but not to the extent of the combined group. In vitro, a combination of glucosamine hydrochloride and chondroitin sulfate acted synergistically in stimulating glycosaminoglycan synthesis (96.6%). Chondroitin sulfate and manganese ascorbate but not glucosamine were effective in inhibiting degra dative enzyme activity. These data suggest that the disease modifying effec t (the ability to retard progression of cartilage degeneration) of a mixtur e of glucosamine, chondroitin sulfate, and manganese ascorbate is more effi cacious than either agent alone.