(A) Representative Western blot analysis of apoptosis-related protein C-caspase3, Bax and Bcl2 in HepG2 treated with PA with or without GUDCA for 24 h. β-Actin was used as loading control (n = 4/group). (B) Annexin V-FITC/PI double staining for apoptotic HepG2 treated with BSA, PA (300 μM), or PA (300 μM) + GUDCA (300 μM) for 24 h. Early apoptotic cells were marked only in green, whereas late apoptotic cells were presented in red with green (n = 3/group). (C) TUNEL assay for apoptotic HepG2 that were treated BSA, PA, or PA + GUDCA for 24 h. All apoptotic cells were marked in red (n = 3/group); scale bars: 100 µm. All data are presented as the mean ± SEM and analyzed by one-way ANOVA followed by the Bonferroni post hoc test; *P<0.05, **P<0.01 versus control.