Figure 4.

ERK inhibitor reversed effects of As₂O₃ on Bmp2 (A) and OCN (B) mRNA expression during osteoblast differentiation in BMSCs isolated from bones of control rats. BMSCs were cultured in differentiation medium (DM) with 0, 0.5, or 1 μM As₂O₃ in the presence (+) or absence (–) of the ERK inhibitor PD98059 (20 μM) for 5–14 days. mRNA expression was determined by real-time PCR. Data are presented as mean ± SD of three independent experiments in triplicate. (C) Effect of PD98059 (10 and 20 μM) alone on gene expression of Bmp2 and OCN. Results are representative of at least three independent experiments.

*p < 0.05, compared with the 0‑μM As₂O₃ + DM group. ^#p < 0.05, compared with the respective As₂O₃ group without PD98059.