Measurement of intracellular ROS level
The Caco2 and IEC-6 cells were plated in 24-well culture plates at a density of 5 × 104 cells·mL-1 and treated with diosmetin (25 and 50 μM) for 2h before challenge with LPS. Then the cells were added in 500 μL of DCFH-DA (10.0 μM) for the detection of ROS, which was photographed by using a confocal microscope (Nikon, Japan), with 400 × magnification. Mitochondrial ROS level determination
The Caco2 and IEC-6 cells were plated in 24-well culture plates at a density of 5 × 104 cells·mL-1 and treated with diosmetin (25 and 50 μM) for 2h before challenge with LPS. Then the cells were added in 1mL MitoSOX Red Mitochondrial Superoxide Indicator (Yesen, Shanghai), incubated at 37 °C in dark for 10 min, washing three times with washing buffer. Finally, the cells were photographed by using a confocal microscope (Nikon, Japan), with 400× magnification.