Effects of juglone on ROS production and mitochondrial transmembrane potential in SGC-7901 cells

To investigate the effects of juglone on ROS production and mitochondrial transmembrane potential (DeltaPsi_m) in SGC-7901 cells in vitro, further to elucidate the apoptosis mechanism. The apoptosis morphological changes of SGC-7901 cells were observed using fluorescence microscope. The level of ROS and DeltaPsi_m of cells were detected by FCM. The change of [Ca²⁺]_i in cells stained with Fluo-3/AM was observed by LCSM. Hoechst 33258 staining assay showed thick granulated fluorescence in condensed nuclei and cytoplasm, and the number of apoptotic bodies was increased with increasing of juglone concentration. The level of ROS at the dose of 5, 10, 15 and 20 muM of juglone was 34.83plusmn1.45%, 42.43plusmn1.36%, 53.73plusmn1.38% and 68.67plusmn1.33%, respectively, which were significantly higher than that in control group (P<0.01). The concentration of Ca²⁺ in cells exposed to juglone for 24 h was increased significantly in a dose dependent manner compared with control group (P<0.01). DeltaPsi_m of treatment groups was 85.53plusmn1.82%, 53.57plusmn2.48%, 46.33plusmn1.46%, 36.43plusmn2.64%, respectively, which were significantly lower than that in control group (P<0.01).Therefore, juglone can increase intracellular level of ROS and concentration of Ca²⁺, decrease DeltaPsi_m and induce the cells apoptosis.