Oxidized Graphene Alleviates Benzo[a]pyrene-Induced Cytotoxicity by Suppressing Mitochondrial Apoptosis Pathways

Environmental carbon nanomaterials such as multi-walled carbon nanotubes (MWCNTs) and graphene oxides (GOs) may interact with aromatic hydrocarbon pollutants, such as benzo[a]pyrene (BaP), in the environment, causing adverse effects on ecosystems and human health. However, the impact of the joint toxicity of carbon nanomaterials and BaP is still unknown. Among all six carbon nanomaterials investigated, MWCNTs-NH2, p-GO, and GO-COOH exhibited some alleviation of the BaP-induced cytotoxicity, while GO-COOH has the most potent inhibitory effect on the cytotoxicity of BaP. Mechanistically, GO-COOH alleviated BaP-induced cell apoptosis and cytotoxicity by down-regulating pro-apoptotic proteins, up-regulating anti-apoptotic proteins, and maintaining the mitochondrial membrane potential. These findings indicate that the physicochemical properties of carbon nanomaterials play a crucial role in modulating BaP’s cytotoxicity.