Fig. 7

ROS production in cells cultured in different types of medium. HT22 cells were cultured in normal glucose medium (25 mM d-glucose, I), high-glucose medium (50 mM d-glucose, II), high-glucose medium + 1.25 μm/L SFN (III), high-glucose medium + 2.5 μm/L SFN (IV) or high-glucose medium + 5 μm/L SFN (V) for 0 or 72 h. ROS were measured using the DCFH-DA fluorescent probe under a fluorescence microscope at a magnification of ×400. The fluorescence intensity was correlated with the ROS level. It was observed that the fluorescence intensity was significantly increased in HT22 cells cultured in high glucose medium without SFN (II) compared with the others (I, III, IV, and V) after culturing for 72 h. ROS, reactive oxygen species; DCFH-DA, dichlorodihydrofluorescein-diacetate