Figure 4.

Nrf2-related signaling was activated by NAC and L-ascorbate in SCP-1 during osteogenic differentiation with CSE. SCP-1 cells were osteogenically differentiated with coincubation of antioxidants NAC 1 mM or L-Asc 200 μM and CSE 5%. After 14 days of treatment, phosphorylated Nrf2 (a), p38 MAPKinase (b), SOD-1 (c), and catalase (d) protein expression levels were detected by Western blot. GAPDH was used as internal control. Each experiment was conducted at least three times independently with triplicate. The statistical significance was determined by the Kruskal-Wallis H test followed by Dunn's posttest. Data are represented as the mean ± SEM, and the significance was represented as ^∗ p < 0.05, ^∗∗ p < 0.01, and ^∗∗∗ p < 0.001 vs the control group.