Inhibitory effect of Kampo medicines on bone resorption in vitro and preventive effect on bone loss in vivo

Abstract

The inhibitory activities of 19 Chinese formulae on osteoclast formation and bone resorption in vitro were investigated. The inhibitory activity on osteoclast formation was evaluated using a mouse bone marrow cell culture in which osteoclast-like multinucleated cells were formed in the presence of parathyroid hormone (PTH). The inhibitory activity on bone resoption was evaluated using PTH-induced resorption of ⁴⁵Ca from ⁴⁵Ca-prelabeled neonatal mouse parietal bone. Among the 19 Chinese formulae, nine showed a strong inhibitory activity on osteoclast formation at a concentration of 50μg/ml, and three of the nine also showed a strong inhibitory activity on bone resorption. Among these three formulae, Bu-Shen-Jian-Gu-Tang showed the most promising activity in a dose-dependent manner on the inhibition of bone resorption. A further in vivo experiment in ovariectomized (OVX) model rats using peripheral quantitative computed tomography (pQCT) revealed its preventive effect on bone loss.