Hispidulin Exerts Anti-osteoporotic Activity in Ovariectomized Mice via Activating AMPK Signaling Pathway

To investigate the effect of Hispidulin on ovariectomy (OVX)-induced bone loss in mice. Female mice subjected to OVX were treated with Hispidulin for 8 weeks. The total body bone mineral density was measured at the beginning and after the OVX at a time interval of 4 weeks. Micro-computed tomography of the tibia, bone histomorphometric analysis of the femur, and biomechanical analysis of tibia, vertebra, and femoral head were performed to fully evaluate the anti-osteoporotic effect of Hispidulin. Western blot analysis was performed to determine the level of activated AMPK. Hispidulin treatment effectively prevented OVX-induced body weight loss and attenuated OVX-induced bone loss. Hispidulin treatment also decreased trabecular spacing in OVX mice. The suppressing effect of Hispidulin on osteoclast surface and number was also found via histomorphometric analysis. Western blot analysis revealed that Hispidulin significantly elevated the activated AMPK levels. Our findings suggest that Hispidulin exerts anti-osteoporotic and bone resorption attenuating effects via activating the AMPK signaling pathway.