A Korean Poly-Herbal Medicine, SMO16, Regulates the RANKL/OPG Bone Remodeling in OVX Rat Model

Bone mass is regulated by bone resorption(osteoclast) and bone formation(osteoblast), and an imbalance be-tween both processes results in osteoporosis. Osteoporosis is characterized by a loss of bone density and regula-tion of bone remodeling is crucial for the treatment of osteoporosis. In this study, we investigated whether SMO16, a Korean polyherbal medicine containing 5 herbal components, could regulate bone remodeling in an ovariectomized(OVX) rat model. To test the effect of SMO16 in the OVX model, the rats were divided into 3 groups: a control group, OVX group, and OVX + SMO16(2.25 g/kg) for 8 weeks(ST group). The expression of osteocalcin(OPC), receptor activator of nuclear factor kappa-B ligand(RANKL), and osteopro-tegerin(OPG) were measured in the femur using specific antibodies. The bone mass was analyzed using dual-energy X-ray absorptiometry. In the OVX group, protein expression of OPC was decreased; however, in the ST group, OPC expression was significantly increased when compared with the OVX group. SMO16 significantly reduces RANKL-positive cells in the OVX rat femur. Additionally, SMO16 increased OPG ex-pression levels. Importantly, SMO16 significantly increased bone density. These data suggest that SMO16 increases bone remodeling by regulating OPC, RANKL, and OPG signaling. SMO16 could be a potential alternative treatment for osteoporosis.