透骨消痛胶囊对兔膝骨关节炎形态学与OPG/RANKL表达的影响

he imbalance of subchondral bone remodeling is a common pathological feature in the progress of osteoarthritis. In this study, using a rabbit model of knee osteoarthritis, we determined the effects of Tougu Xiaotong capsule (TGXTC) on both cartilage and subchondral bone, and investigated osteoprotegerin (OPG), an inducer of bone formation, and receptor activator of nuclear factor-κB ligand (RANKL), a regulator of bone resorption in the subchondral bone, further exploring its protective role in subchondral bone remodeling. The rabbit model of knee osteoarthritis, which was induced by a modified Hulth' method, was treated with TGXTC or glucosamine hydrochloride for 4 or 8 weeks. Afterwards, the tibia and femur were harvested for observation of cartilage histology, and the subchondral bone was observed by scanning electron microscopy; respectively, the expression of OPG and RANKL at both the gene and protein levels was determined by real-time PCR and western blot. TGXTC and glucosamine hydrochloride were found to mitigate cartilage injury, reduce trabecular number and thickness, and accelerate trabecular separation. We also found that the decreased OPG mRNA and protein expression, and the increased RANKL mRNA and protein expression, as well as the lower OPG/RANKL ratio were observed in the both in TGXTC and hydrochloride group. Taken together, these results suggest that TGXTC could mitigate cartilage injury and the subchondral sclerosis, and delay the pathological development of osteoarthritis, partly through decreasing OPG expression and increasing RANKL expression, which reduces the OPG/RANKL ratio, suppressing excessive bone formation.