Micheliolide prevents estrogen deficiency-induced bone loss via inhibiting osteoclast bone resorption.

Osteoporosis is one of the major health problems characterized by decreased bone density and increased risk of fractures. Nowadays, the treating strategies against osteoporosis are efficient, but still have some drawbacks. Micheliolide, a guaianolide sesquiterpene lactone isolated from Michelia compressa and Michelia champac, has been reported to have anti-inflammatory effects. Here, our data suggest that Micheliolide could protect mice from ovariectomy induced bone loss. According to the Micro-CT scan and histomorphometry quantification data, Micheliolide treatment inhibits excessive osteoclast bone resorption without affecting bone formation in estrogen deficiency mice. Consistently, our data suggest that Micheliolide could inhibit osteoclastogenesis in vitro. Additionally, we confirmed that Micheliolide inhibits osteoclasts formation via inhibiting P38 MAPK signaling pathway, and P79350 (a P38 agonist) could rescue this effect. In summary, our data suggest that Micheliolide could ameliorate estrogen deficiency-induced bone loss via attenuating osteoclastogenesis. Hence, Micheliolide could be used as a novel anti-resorptive agent against osteoporosis.