Polystyrene nanoparticles leads to dysfunction in DNA repair

MethodsWe exposed Caco-2 cells to various concentrations of PNPs and monitored cytotoxicity, ROS levels, PARP-1-dependent apoptosis, DNA damage, and changes in DNA damage response (DDR) gene expression.ResultsThe results indicated that although PNPs did not directly cause SSBs or DSBs, as evidenced by comet assays and γH2AX staining, they induced oxidative stress and significantly altered the expression of genes required for DDR. In particular, critical genes involved in the base excision repair (BER) pathway and DSBs repair were downregulated, suggesting a potential impairment of the cell’s ability to repair oxidative DNA damage.