Figure 6: Measurement of intracellular GSH and GSSG in control and alantolactone-treated HepG2 cells for various time points. Cells were cultured in 6 well plates and treated with or without 40 μM alantolactone for 3, 6, and 12 h. Intracellular GSH and GSSG were measured according to the instructions of kit. Data are expressed as mean ± SD ( ). Columns not sharing the same superscript letter differ significantly ( ).