Figure 2. Delineation of the mechanism underlying the enhancing effect of MCC-555 on the osteoblastic differentiation of C3H10T1/2 cells. (A) Western blot analyses. Confluent C3H10T1/2 cells were induced to undergo osteoblastic differentiation with either vehicle (Untreated) or MCC-555 co-treatment (5 μM, M5). Cells were harvested at the times as indicated for the preparation of nuclear fractions. β-catenin and Lamin B (as a normalizer) were detected and quantitated. Relative β-catenin levels were calculated by comparing the normalized signals of MCC-555-treated cells to that of the untreated cells at day 4 (to which a value of 1 was assigned). Data represent the mean ± S.D. from three experiments. One-way ANOVA plus Scheffe’s post hoc tests were used to analyze the differences. *, P<0.05 versus the untreated cells of day 4. Student’s t-test was used to analyze the difference between the untreated and M5-treated cells at day 20. (B) Osteoblastic induction. Confluent C3H10T1/2 cells were induced to undergo osteoblastic differentiation. Five μM MCC-555 (M5) was added at days 0, 5, 10, and 15 as indicated in the schematic presentation (upper), and was changed along with the media every 3 days. Cells were stained with Alizarin Red S at the 24th day. Representative photos are shown (lower). The stains were quantitated, and the signals of the MCC-555-treated cells were compared to that of the vehicle-untreated cells (U) (to which a value of 1 was assigned). One-way ANOVA plus Scheffe’s post hoc tests were used to analyze the differences. *, P<0.05 versus the untreated cells.