Fig. 2

Gallic acid (GA) inhibits intracellular reactive oxygen species (ROS) production. a Green fluorescence indicates intracellular ROS in RAW264.7 with or without lipopolysaccharide (LPS). b Fluorescence statistics of RAW264.7 macrophages. c Flow cytometry assay quantified intracellular ROS in RAW264.7 cells. d Statistical results of flow cytometry. e Green fluorescence indicates intracellular ROS in human corneal epithelial cells (HCECs) with or without hypertonic stimulation. f Fluorescence data from (e). g Flow cytometry assay quantified intracellular ROS in HCECs. h Bar graphs of (g). RAW264.7 macrophages were pre-treated with GA (100 µM) for 16 h followed by the stimulation of LPS (1 µg/mL) for another 8 h. HCECs were pre-treated with GA (100 µM) for 23 h followed by the stimulation of sodium chloride solution (90 mM) for another 1 h. Data are presented as mean ± SD (n = 3). DCF, 2,7-dichlorofluorescein; FITC-A, fluorescein isothiocyanate-area; ****P < 0.001 compared to the LPS group