Synergistic Antioxidant and Anti-Apoptotic Effects of Captopril and Spironolactone in Streptozotocin-Induced Damage to Human Granulosa-Like KGN Cells

Background: Diabetes mellitus causes ovarian granulosa cells to undergo oxidative stress, inflammation, and apoptosis, all of which have a negative impact on female reproductive health. Although there are currently few treatment options, granulosa dysfunction under hyperglycemia contributes to infertility. This study evaluates the cytoprotective potential of captopril and spironolactone, individually and in combination, against Streptozotocin (STZ)-induced damage in human granulosa-like KGN cells. Materials and Methods: Following a 24-hr exposure to STZ (5 mM), KGN cells were treated with either 50 μM captopril, 25 μM spironolactone, or both. Hoechst 33258 staining and the TUNEL assay were used to measure apoptosis. Western blot analysis was used to examine the expression of Nrf2, cytochrome c, and cleaved caspase-3. One-way ANOVA and Tukey's post hoc test (p<0.05) were used for statistical analysis. Results: Exposure to STZ markedly decreased Nrf2 levels while increasing nuclear condensation, DNA fragmentation, and pro-apoptotic protein expression. Separately, captopril and spironolactone decreased apoptotic indices and partially restored antioxidant defences. Interestingly, the combination treatment had a synergistic effect, increasing Nrf2 expression and significantly decreasing apoptotic markers (p<0.001). Conclusion: Combined treatment with captopril and spironolactone confers enhanced protection against STZ-induced apoptosis in granulosa cells, primarily by modulating oxidative stress and apoptosis pathways. This supports the potential for drug repurposing in preserving ovarian function under diabetic conditions.