Effects of ACS6 on the activation of caspase-3 in PC12 cells. After pretreated with 16 μmol/L ACS6 for 30 min, PC12 cells were exposed to 5 mmol/L homocysteine (Hcy) for 24 h. The activation of caspase-3 in PC12 cells was analyzed by Western blot using an anti-cleaved caspase-3 antibody. Western blot images show representative results from three independent experiments. In all blots, staining for β-actin was used as a loading control. The level of cleaved caspase-3 expression obtained in each experimental condition was calculated as a fold of the control. Values are the mean ± SEM (n= 3). ***P <0.001, versus control; ###P< 0.001, versus 5 mmol/L homocysteine-treated alone group.