Effect of alendronate-loaded bone cement on osteoblast

Objective: To determine the effect of bone cement, with different amounts of alendronate on osteoblast, and determine the cytotoxicity of alendronate-integrated bone cement from the viewpoint of cell biology. Methods: According to different additions (0, 10, 50, 100, 500, 1000 mg) of alendronate in 50 g Cemex®XL bone cement powder, the experiments were divided into 6 groups, namely G₀-G₅ groups. In all groups, the adhesive capacity of osteoblast-like cells MG-63 was evaluated by electron microscope, the optical density (OD) value of cells by MTT colorimetry method, the alkaline phosphatase activity (AKP) by AKP assay kit, the apoptosis rates by Annexin-V-FITC apoptosis detection kit, and the bone mineralization potentiality by phase contrast microscope. Results: The adhesive capacity of MG-63 was good in all groups. Compared with the G₀ group, the cell apoptosis was inhibited in G₁-G₄ groups while in G₅ group the cell apoptosis was promoted and cell proliferation was inhibited (P<0.05). In all groups, no significant difference was found in alkaline phosphatase activity and bone mineralization potentiality (P>0.05). Conclusion: Less than 500 mg alendronate added in Cemex®XL 50 g bone cement powder has no cytotoxicity on osteoblasts.