Figure 4. Paeoniflorin (PF) inhibits H₂O₂-induced reactive oxygen species (ROS) production in ARPE-19 cells. A: APRE-19 cells were treated with different concentrations of H₂O₂ (50–800 μM). For measuring H₂O₂ production, the cells were then labeled with 2’,7’-dichlorodihydrofluorescein diacetate (H₂DCFDA). Quantitative analysis was performed by measuring fluorescence intensity. Each value represents the mean±SEM of three independent experiments (n=3 experiments, *p<0.05). B: ARPE-19 cells were treated with 200 μM H₂O₂ and different concentrations of PF (50–200 μg/ml). For measuring H₂O₂ production, the cells were then labeled with H₂DCFDA. Quantitative analysis was performed by measuring the fluorescence intensity relative to the control. Each value represents the mean±SEM of three independent experiments (n=3 experiments, *p<0.05). C: For measuring H₂O₂ production, the cells were labeled with H₂DCFDA. Figures were selected as representative data from three independent experiments. Scale bar, 100 μm.