Effects of fullerene C60 nanoparticles on A549 cells

• C60 NPs could readily enter A549 cells and showed no significant toxicity.
• C60 NPs could lead to an increase of intracellular ROS.
• More GSH were generated to maintain cellular oxidation–reduction equilibrium.
• Cell autophagy was found to be activated to keep the cell safe.

Fullerene C60 nanoparticles (C60 NPs) have been widely applied in many fields due to their excellent physical and chemical properties. As production and applications of C60 NPs expand, public concern about the potential risk to human health has also risen. The toxicity of C60 NPs was evaluated by the CCK-8 assay using the cultured human epithelial cell line A549. Cellular uptake of the C60 NPs was observed by TEM imaging. In our findings, C60 NPs could readily enter A549 cells and showed no significant toxicity. Exposure of cultured A549 cells to C60 NPs led to an increase of intracellular reactive oxygen species (ROS) while glutathione reductase activity was probably activated to generate more GSH to maintain a cellular oxidation–reduction equilibrium. The A549 cells responded to the ROS increases through the inauguration of autophagic responses, aimed at restoring cellular health and equilibrium.