Effects of salvia miltiorrhiza on osteoblastic cell line of MC3T3-E1

Abstract

AIM: Orthodontic tooth movement is mediated by bone remodelling. Sufficient bone is essential for the success and effectiveness of orthodontic treatment. It has previously been found that salvia miltiorrhiza extract (SM), a commonly used Chinese herb in cardiac disease to enhance blood perfusion, could increase bone formation in vivo. The aim of this study was to investigate the effects of SM on bone cells in vitro, to obtain a better understanding on how SM can promote bone remodelling. MATERIALS AND METHOD: MC3T3-E1, an osteoblastic cell line, was cultured with SM for different time intervals (24, 48 and 72 hours), whereas the control group consisted of cells cultured without any intervention. The mRNA expressions of alkaline phosphatase (ALP), osteocalcin (OCN), osteoprotegerin (OPG) and the receptor activator of nuclear factor kappa β ligand (RANKL) were examined by real-time polymerase chain reaction. RESULTS: The expression of ALP showed an early increase at 24 and 48 hours by 50 and 13 per cent, respectively (P < 0.001). OCN was decreased by 22 per cent at 24 hours (P < 0.001) but increased by 50 and 88 per cent at 48 and 72 hours, respectively (P < 0.001). OPG was up-regulated by 10 per cent at 48 hours (P < 0.01) and 68 per cent at 72 hours (P < 0.001), while RANKL showed an early increase at 24 and 48 hours by 45 (P < 0.001) and 36 (P < 0.01) per cent, respectively. OPG/ RANKL was first down-regulated and then up-regulated. CONCLUSION: SM enhances bone remodelling by regulating the gene expressions of ALP, OCN, OPG and RANKL. It is a potential medicinal herb that could be utilized in the application that requires stimulation in bone cell activities.