The influence of alendronate on the expression of osteoclast associated genes in an osteoblast-osteoclast co-culture system

Objective: To study the influence of alendronate on osteoclastogenesis,bone resorption and expression of osteoclast-associated genes in an osteblast-osteoclast co-culture system.Methods: Mice calvarial osteoblasts were harvested by trypsin digestion and bone marrow cells were obtained.The cells were co-cultured in α-MEM,PGE2(10-6 M) and VitD3(10-8 M) were added in the cultures to induce osteoclastogenesis.The cells treated by ALN(10-6 mol/L) were in ALN group,and those without ALN in control group.Osteoclastogenesis and their resorption function were examined by TRAP staining and scanning electron microscope(SEM) observation of dentin resorption lacunaes.Gene expressions of NFATc1,c-Fos,RANKL and OPG were detected by Real-time PCR.Results: TRAP positive multinuclear cells and resorption lacunaes were observed in both groups.However,control group showed more TRAP positive multinuclear cells and more resorption lacunaes than ALN group.Real-time PCR detection showed that gene expressions of NFATc1,c-Fos,RANKL and OPG were higher in control group than in ALN group.Conclusion: ALN can inhibit osteoclastogenesis,resorption function,and gene expression of osteclast-associated genes in the osteoblast-osteoclast co-culture system.