Herba epimedii flavonoids suppress osteoclastic differentiation and bone resorption by inducing G2/M arrest and apoptosis

►Icariin could induce apoptosis and G2/M cell cycle arrest in RAW 264.7 cells. ► Herba epimedii flavonoids could regulate the formation and activity of osteoclasts. ► TRAP, CA II, CTSK and MMP-9 were significantly down-regulated by the treatment of HEF. ► The free hydroxyl group at C-7 of baohuoside-1 played an important role in the SAR. ► The above changes are probably mediated by interaction with estrogen receptors.