Fig. 5.

OA treatment inhibits responses of activated intestinal epithelial cells. Caco-2 monolayers were treated for 24 h with the indicated doses of OA and viability was measured (a). Caco-2 monolayers, pretreated for 30 min with different doses of OA, were incubated with the indicated stimuli. b After 24 h, cells were stained with DHE and superoxide anion accumulation was analyzed by fluorescence microscopy. Representative microphotographs (objective lens × 40) and quantification. c After 1 h, cells were stained with DCFH-DA and intracellular ROS-production was analyzed in a microplate reader. d After 24 h, IL-8 concentration in the cell-culture supernatant was measured by commercial ELISA. The assays were performed in duplicates, n = 3. Results were expressed as the mean ± SEM. *p < 0.001 and **p < 0.01 vs control; and ^‡p < 0.001, ^‡‡p < 0.01, and ^‡‡‡p < 0.05 vs stimuli without OA