Effect of Arendronate on Proteoglycan Production and Cell Metabolism in Bovine Articular Chondrocytes in Alginate Culture

INTRODUCTION: Bisphosphonates are well known potent inhibitors of osteoclast activity and are widely used in the clinical treatment of osteoporosis and various systemic metabolic bone diseases. Alendronate, a nitrogen-containing bisphosphonate, is a potent inhibitor of bone resorption widely used for the treatment and prevention of osteoporosis. Recently, bisphosphonates have been demonstrated to have chondroprotective effects, to reduce the incidence and progression of osteophytes in animal models of osteoarthritis, and to modify osteoblast function in vitro. In an observational epidemiological study, compared to non-users, women on alendronate had less severe knee pain and less subchondral bone attrition and bone marrow lesions. Proteoglycan loss is one of the first signs of osteoarthritis. There is little information however on the effect of alendronate on the accumulation of glycosaminoglycan (GAG) in cartilaginous tissue. In this study, we examine how concentrations of alendronate influence the rate of GAG accumulation in cartilagious cells in a three-dimensional culture system.