Effects of Icariin on osteoclastic bone resorption and apoptosis in vitro

Objective:To observe the effect of Icariin on osteoclastic bone resorption and apoptosis in vitro and explore the mechanism of Icariin in preventing osteoporosis.Methods: Osteoclasts were seperated from long-limb bones of new born rabbits,cultured with glass slices and bone slices,and treated by 10-7,10-6,5×10-6,10-5 mol/L Icariin.Osteoclasts were identified by observing live cells with phase contrast microscope,HE staining,TRAP staining and toluidine blue staining of bone resorption pits.The number of bone resorption pits were counted as well as the surface area of bone resorption on bone slice.Osteoclasts were stained with acridine orange.The rates of apoptotic osteoclasts were observed under fluorescence microscope.Results:Comparing with the blank control group,the rates of apoptotic osteoclasts increased obviously and the number and area of bone resorption pits decreased evidently with increasing dose in those groups treated by 10-6,5×10-6,10-5 mol/L Icariin.The differences between control group and those groups treated by 10-6,5×10-6,10-5 mol/L Icariin were significant if P0.05.Conclusion:Icariin can induce osteoclast apoptosis and inhibit bone resorption in dose-dependent manner.