Fig. 3

Metformin induced apoptosis, increased ROS production, and decreased the mitochondrial potential in vitro. a RSCL and RRCL were exposed to control or metformin (16 mM) for 48 h, and then the percentage of cells undergoing apoptosis (Annexin V + cells) was determined by flow cytometry. Asterisk indicates that the differences were significant at P < 0.05. b Oxidative stress induced by metformin was determined by comparing dihydrorhodamine-123 (DHR-123) fluorescence intensity at 24 h post-metformin exposure to DHR-123 fluorescence of controls. All data were normalized to the control cell as 100% ROS production. Data represented mean ± SD derived from 3 independent experiments. Asterisk means P < 0.05. c RSCL and RRCL were cultured for 48 h in the absence or presence of metformin (16 mM). Subsequently, cells were stained for 30 min at 37 °C with DiOC6 followed by flow cytometry analysis. Low DiOC6 population was gated for low mitochondrial outer membrane potential (∆Ψm-Low) and FCCP was used as a positive control. All data represented mean ± SD derived from 3 independent experiments