Induction of HO-1 and Nrf2 expression by SHME in C2C12 cells. Cells were incubated with various concentrations of the SHME for 6 h (A) or for the indicated periods with 300 μg/mL SHME (B). The levels of HO-1 and Nrf2 proteins were determined by Western blot analyses, and representative blots of three independent experiments are shown. Actin was used as a loading control. The numbers represent the average densitometric analyses as compared with actin in, at a minimum, two or three different experiments.