Celecoxib prevents juxta-articular osteopenia and growth plate destruction adjacent to inflamed joints in rats with collagen-induced arthritis.

The effect of celecoxib, a selective cyclooxygenase-2 inhibitor, on juxta-articular osteopenia and growth plate destruction adjacent to inflamed joints was investigated in rats with collagen-induced arthritis. Forty rats were assigned to the following six groups: (1) an untreated arthritis group; (2-5) arthritis rats receiving indomethacin (3 mg/kg per day), dexamethasone (0.2 mg/kg per day), or celecoxib (5 or 50 mg/kg per day), and (6) normal control rats. Drugs were administered for 2 weeks from the onset of arthritis. Then the hind paws were measured. Juxta-articular osteopenia and growth plate destruction adjacent to inflamed joints were also assessed using plain radiography, bone mineral density measurement, histology, and histomorphometry. Each treatment reduced inflammation, but only dexamethasone and high-dose celecoxib prevented bone loss adjacent to inflamed joints and significantly decreased bone resorption. In contrast, no treatment affected bone formation parameters. Growth plate destruction adjacent to inflamed joints was prevented by indomethacin, dexamethasone, and high-dose celecoxib. Although dexamethasone abolished inflammation, growth plate destruction was still observed. In conclusion, among the various drugs tested, only celecoxib had a preventive effect on both growth plate destruction and bone loss adjacent to inflamed joints in this arthritis model.