Thymoquinone Reduces Bisphenol A-Induced Increases in Apoptosis and Oxidative Toxicity Through the Modulation of...

Bisphenol A (BPA) is an industrial and environmental toxin. Chronic BPA exposure-mediated apoptosis and Ca²⁺ influx have been linked to the development of certain reproductive problems and granulosa cell damage in humans by raising cytosolic (cROS) and mitochondrial (mROS) free reactive oxygen species. However, these effects were modulated by upregulating glutathione (GSH) and glutathione peroxidase (GSHPx), while downregulating the TRPM2 channel activity. In human KGN granulosa cells, we aimed to investigate the protective function of the antioxidant thymoquinone (TQ) against BPA-induced TRPM2 channel activation, oxidative, and apoptotic changes. Five experimental groups were established: control, TQ, BPA, BPA + TQ, and BPA + TRPM2 antagonist [2-aminoethoxydiphenyl borate (2APB) and (N-p-Amylcinnamoyl)anthranilic acid (ACA)]. TRPM2 agonists (H₂O₂ and ADP-ribose) and BPA-induced TRPM2 stimulations (Ca²⁺ influx and TRPM2 current density) were downregulated after incubation with TQ and ACA/2APB. BPA-mediated increases in Zn²⁺, Fe²⁺, oxidants (mROS and cROS), apoptotic markers (caspase-3, caspase-8, and caspase-9), and cell death were decreased by TQ and ACA therapy. On the other hand, BPA-induced decreases in GSH and GSHPx levels were reversed after the TQ and ACA incubations. In conclusion, TQ reduced the BPA-induced increase in Ca²⁺ influx, Fe²⁺, Zn²⁺, apoptosis, and oxidative granulosa cell injury via the suppression of TRPM2.