Figure 8.

Screening for vitamin D (VD) analogs that reduce c-Fos protein and inhibit osteoclast differentiation more potently than 1α,25(OH)₂D₃. The effects of 1α,25(OH)₂D₃ (open circles) and its analogs (DD281, DD280, and DD208) on the c-Fos protein level in osteoclast precursor cells (A and B) and the formation of TRAP-positive multinucleate osteoclasts (C) at the indicated concentrations are shown. The lower bands in A show β-actin as an internal control for protein loading. Filled circles, rectangles, and triangles (B and C) represent DD281, DD280, and DD208, respectively. Data are expressed as a percentage of the value for vehicle-treated cultures.