Inhibitory activity on RANKL-mediated osteoclastogenesis of Glossogyne tenuifolia extract

Receptor activator of nuclear factor kappa B ligand (RANKL)-induced activation of NF-κB and MAPKs signaling pathways is critical to osteoclastogenesis. Glossogyne tenuifolia has been used as an antipyretic, detoxification and anti-inflammatory herb tea in Penghu Island, Taiwan. This study investigated the effects of G. tenuifolia ethanolic extract (GTE) on the formation of RANKL-activating osteoclasts and expression of signaling pathways using a RAW264.7 cells model. GTE significantly inhibited the RANKL-induced formation of TRAP-positive multinucleated osteoclasts in a dose-dependent manner. GTE inhibited RANKL-induced activation of nuclear factor of activated T-cells (NFATc1) and suppressed the phosphorylation of NF-κB/p65 and JNK. Additionally, GTE reduced the phosphorylated forms of osteoclast survival-related signaling molecules, including NF-κB, JNK, p38 and Akt. Taken together, these results reveal that GTE may have potential in the development of health food against osteoclast-related diseases such as osteoporosis.