Bone Abstracts

This study examined the anti-osteoclastogenic effect of n-butanol extracts of Panax notoginseng on the receptor activator of NF-kB ligand (RANKL) induced RAW264.7 cells. Panax notoginseng is commonly used to treat chronic liver disease. Notoginseng has many beneficial effects, such as the suppression of liver fibrosis and anti-cancer activities. Notoginseng contains several biologically active components, such as ginsenosides Rb₁, Rg₁, Rd and Re and notoginsenoside R1.The effects of n-butanol extract of Panax notoginseng (bPN) on osteoclasts were examined by measuring the following: the cell viability, the formation of tartrate-resistant acid phosphatase (TRAP) (+) multinucleated cells, RANK/RANKL signaling pathways and mRNA expression of osteoclast-associated genes. bPN inhibited the formation of RANKL-stimulated TRAP (+) multinucleated cells. bPN also inhibited the RANKL-stimulated activation of ERK signaling, and inhibited the RANKL-stimulated degradation of I?B in the RAW264.7 cells. In addition, the RANKL-stimulated induction of NFATc1 transcription factors was abrogated by bPN. bPN decreased the mRNA expression of osteoclast-associated genes, including TRAP and cathepsin K in the RAW264.7 cells. Our data demonstrate that bPN inhibits osteoclastogenesis by inhibiting RANKL-induced activation of signaling molecules and transcription factor in osteoclast precursors.