FIGURE 1.

Pb inhibits osteogenesis, which is partially restored by co-treatment with Wnt3a. Mouse calvarial osteoblasts were differentiated to form bone nodules and treated with 0 (control (Ctrl)), 0.5, 2.0, and 5.0 μm Pb and in the presence of 50 ng/ml Wnt3a. A and C, mineralization was assessed by alkaline phosphatase staining (A) on day 10 and alizarin red staining (C) on day 20. Scl, sclerostin. B and D, images are representative of one trial; quantification of alkaline phosphatase (B) and alizarin red (D) staining was performed with ImageJ. Data represent mean ± S.E. for three trials. *, p < 0.05 versus control, #, p < 0.05 versus 2.0 μm Pb.