Fig. 4.

U0126 attenuates the activations of Erk1/2, CREB and CRE. Cultured SH-SY5Y cells were pre-treated with 10 µM U0126 for 3 h before the herbal treatment (0.5 mg/mL) for different duration. a Total Erk1/2 (T-Erk1/2) and phosphorylated Erk1/2 (P-Erk1/2) and b total CREB (T-CREB) and phosphorylated CREB (P-CREB) were investigated by specific antibodies (left panel). TPA (100 nM) and FSK (10 µM) served as positive control for activation of Erk1/2 and CREB, respectively. The band density was measured by densitometer (right panel). c In pCRE-Luc transfected cultures, cells were pre-treated with fresh medium/U0126 (10 µM) for 3 h before the treatment of DBT (0.125, 0.25, 0.5 mg/mL) for 48 h. Cells were collected to determine the luciferase activity. FSK (10 µM) served as a positive control. **p < 0.01; ***p < 0.001 compared with control