The effect of mifepristone on apoptosis and caspase-3 activation in human ovarian luteinized granulosa cells

ObjectiveTo investigate the effect of mifepristone, an oral contraceptive, on apoptosis in human ovarian luteinized granulosa cells.Study designHuman ovarian luteinized granulosa cells were treated in vitro with 1.25, 2.5, 5.0, 10.0, or 20.0 μM of mifepristone. Nuclear morphology, apoptosis ratio, and level of caspase-3 expression were determined with immunofluorescence microscopy, the terminal deoxynucleotidyl transferase mediated nick end labeling (TUNEL) assay, and flow cytometry.ResultsWe found that mifepristone-treated cells contained single condensed chromatin with multiple nuclear fragments, which is morphologic evidence of apoptosis. A significant difference was observed in the TUNEL assay between mifepristone-treated cells and control cells (P < 0.05). Consistent with the results of the TUNEL assay, the fluorescence intensity of caspase-3 in drug-treated cells was also significantly different (P < 0.05) from control cells; specifically, the difference between cells treated with different doses of drugs was much smaller and negligible.ConclusionFrom these results, we propose that mifepristone induces human ovarian luteinized granulosa cells to undergo apoptosis by activating caspase-3.