Apoptosis kits

Lecithin and cholesterol were purchased from Aladdin (China). Ginsenoside, platycodin and glycyrrhizic acid were obtained from Shanghai Yuanye Biotechnology Co (Shanghai, China). Coumarin 6 fluorescent dye was purchased from Adamas (Shanghai, China). MTT kits and apoptosis kits were purchased from Shanghai Beyotime Biotechnology Co (Shanghai, China). The chemical reagents used in this experiment were purchased from Aladdin (China). The dialysis bag was purchased from Beijing Bailingwei Company (Beijing, China).

The cells were seeded in 6-well plates at a density of 2 × 10⁵ cells/well and cocultured with graded concentrations of phillyrin (5, 10 and 20 μM) for 24 hours. Then, 400 μM H₂O₂ was added to the cells, followed by incubation for 6 hours. The cells were washed with PBS and thoroughly mixed with 295 μL of binding buffer, in line with the instructions of apoptosis kits (Beyotime Biotechnology, Shanghai, China). Subsequently, the cells were stained with 5 μL of Annexin V-fluorescein isothiocyanate (FITC) and 10 μL of propidium iodide (PI) and left in the dark at room temperature for 25 minutes. Apoptosis was assessed using flow cytometry (BD Biosciences, New Jersey, USA).