Nuclear staining to evaluate the anti-apoptotic effect of ACS6. After pretreated with 16 μmol/L ACS6 for 30 min, PC12 cells were exposed to 5 mmol/L homocysteine (Hcy) for 24 h and incubated with 5 mg/L Hoechst 33258 for 30 min. (A) Representative morphology visualized under a fluorescence microscope (10 × objective, BX50-FLA, Olympus). Cells with brightly fluorescent and fragmented nuclei were apoptotic. (B) Quantitative analysis of the percentage of apoptotic cells. Values are the mean ± SEM (n= 5). ***P< 0.001, versus control group; ###P< 0.001, versus 5 mmol/L homocysteine-treated alone group.