NEW YORK (Reuters Heath) - Rabbits given glucosamine hydrochloride after induced osteoarthritis had lower rates of subchondral bone turnover afterwards, thereby slowing the process of bone demineralization, researchers report in the May issue of Arthritis and Rheumatism.

Dr. Suzanne X. Wang and associates at the University of Toronto in Ontario, Canada, performed anterior cruciate ligament (ACL) transection surgery to induce osteoarthritis in 16 rabbits. Ten healthy rabbits served as controls. Eight surgical rabbits and six controls were given glucosamine hydrochloride 100 mg daily.

Eight weeks after surgery, knee articular cartilage was examined macroscopically at necropsy, and bone mineral density (BMD) was measured in the dissected distal femur and proximal tibia. Subchondral trabecular bone turnover, architecture and connectivity were evaluated. Subchondral plate thickness and mineralization of tibial sections were also evaluated.

Dr. Wang and colleagues report that most of the transected joints had some degree of cartilage damage, and the animals with induced osteoarthritis "had significantly increased subchondral bone turnover and lower BMD, bone volume, connectivity and bone mineralization."

"The high bone turnover was significantly reduced in glucosamine-treated animals that underwent ACL transection," Dr. Wang and colleagues report. "In fact, there were no significant differences between the ACL transection/glucosamine group and the control/glucosamine group in most of the bone parameters studied."

The researchers conclude, "These inhibitory effects of glucosamine on subchondral bone change in the early phase of surgically-induced OA suggest a possible novel mechanism of glucosamine to partially protect cartilage from degeneration."