Activation of TAZ by XMU-MP-1 inhibits osteoclastogenesis and attenuates ovariectomy-induced cancellous bone loss

Osteoporosis is a metabolic bone loss disorder usually accompanied by overactivated osteoclast formation and increased bone resorption. Transcriptional co-activator with PDZ-binding motif (TAZ) is an emerging potential target for the treatment of osteoporosis. Our previous research showed that TAZ overexpression inhibited osteoclast formation while TAZ silencing had the opposite effect. In addition, TAZ knockout in mouse osteoclasts induced osteoporosis in animal experiments. XMU-MP-1 (XMU) is a selective MST1/2 inhibitor that can theoretically activate TAZ; however, its effect on osteoporosis remains unknown. In this study, we found that XMU treatment significantly increased TAZ expression in osteoclasts and inhibited osteoclast formation in vitro; however, this inhibitory effect was eliminated after the deletion of TAZ. Furthermore, XMU treatment upregulated TAZ expression in osteoclasts and alleviated ovariectomy (OVX)-induced osteoporosis in bilateral OVX mouse models. These findings suggest that XMU can effectively activate TAZ and that pharmacological activation of TAZ may be a promising option for the treatment of osteoporosis.