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

Abstract

Objective To investigate the effect of mifepristone, an oral contraceptive, on apoptosis in human ovarian luteinized granulosa cells. Study design Human 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. Results We 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. Conclusion From these results, we propose that mifepristone induces human ovarian luteinized granulosa cells to undergo apoptosis by activating caspase-3.