Flow cytometry for cell apoptosis analysis

For cell apoptosis analysis, Annexin V-FITC apoptosis detection kit (Abcam, UK) was used. Briefly, cells (HepG2 and SMMC-7721) were seeded at a density of 10⁶ cells/well in 12-well plates. After 48 h treatment with polydatin (1, 3, 10, 30, and 100 µM), the cells were washed with cold phosphate buffered saline, and then incubated with Annexin V-FITC/PI at room temperature for 5 min in the dark. The fluorescence of the cells was detected by flow cytometry by using a FITC signal detector and a PI signal detector (BD Biosciences, USA).