Chondroprotective Effect of Alendronate in a Rabbit Model of Osteoarthritis

The aim of this study was to determine how alendronate (ALN) alters cartilage degeneration and periarticular bone quality in a rabbit anterior cruciate ligament transection (ACLT) model of osteoarthritis (OA). Thirty rabbits underwent an ACLT on the left knee and a sham operation on the right knee. Fifteen rabbits received weekly subcutaneous injections of ALN (0.14 mg/kg) and 15 rabbits (the control [cont] group) received saline. Animal knees were divided into four groups: cont/sham, cont/ACLT, ALN/sham, and ALN/ACLT. Histological, radiological, and immunohistochemical indices were evaluated for each group. Bone volume ratios by micro-computed tomography showed that ALN prevented periarticular bone loss. Histologically, the cont/ACLT group had significantly worse cartilage damage than the cant/sham group 12 weeks after the surgery. However, the ALN/ACLT group had mild cartilage degeneration compared with that of the ALN/sham group. Immunohistochemical analysis showed that ALN suppressed the expression of matrix metalloproteinase-13, interleukin-1 beta, type-X collagen, vascular endothelial growth factor, and receptor activator of nuclear factor kappa B ligand in OA cartilage. ALN had a chondroprotective effect in an experimental rabbit model of OA. (C) 2011 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 29:1572-1577, 2011