Cinnamon induces apoptosis in SiHa cells through dysregulation of mitochondrial membrane potential. (A) SiHa cells were treated with different concentrations of ACE-c (0-80 μg/ml) followed by Annexin V-FITC and PI staining to analyze the effect of cinnamon in apoptosis. This was determined by FACS analysis showing the percentage of early (lower right quadrant) and late (upper right quadrant) apoptotic cells. (B) Flow cytometric analysis of the rapid calcium release in SiHa cells after treatment with cinnamon. Cells (5 × 103 cells) were treated with different doses (0-80 μg/ml) of ACE-c for 24 h. This was followed by loading the cells with Fluo-3/AM for 1 h before analyzing in calcium-free HBSS. Ionomycin was used as a positive control. Fluorescence intensities were measured with FACS Calibur flowcytometer. The data represents mean ± SD of five independent experiments. (C) Confocal images showing mitochondrial membrane depolarization induced by cinnamon. Control and cinnamon-treated SiHa cells were stained with JC-1 and the staining pattern was monitored by confocal laser scanning microscopy. For detection of J-aggregate form (red) (Panel II) and J-monomer alone (green) (Panel I), Argon-Krypton laser line was excited at 590 nm and 527 nm, respectively. Panel III represents the merge images. (D) Flow cytometric analysis with JC-1 dye showing decrease in red to green fluorescence ratio. Control (5 × 105) and cells treated with various concentrations (0-80 μg/ml) of ACE-c were stained with JC-1 dye for 30 min. Fluorescence intensities were measured with FACS Calibur flowcytometer. The data represents mean ± SD of five independent experiments.