FIGURE 1.

ER stress plays an important role in bone formation and is regulated by salubrinal (SAL) concentration. A‐B, Osteogenic induction in POBs for 7 d with salubrinal administered at 0.2, 1 or 5 μmol/L in the presence of ER stress inducer tunicamycin (Tm; 100 ng/mL). After 48 h, ALP expression (black, 100×) decreased with Tm treatment, which was reversed by SAL. C, CCK8 assay for POBs showing the same trend. D‐E, Representative Western blots showing SAL’s protection of osteogenesis against ER stress. The expression of Runx2/β‐actin protein increased and the expression of p‐eIF2α/eIF2α decreased with recovery of the ER. Data were presented as the ratio with β‐actin and mean ± SD. The asterisks (*) represent P < .05. VC, vehicle control