Silver Nanoparticles Induce Mitochondrial Protein Oxidation in Lung Cells Impacting Cell Cycle and Proliferation

Silver nanoparticles (AgNPs) are widely used nanomaterials in both commercial and clinical biomedical applications, due to their antibacterial properties. AgNPs are also being explored for the treatment of cancer in particular in combination with ionizing radiation. In this work, we studied the effects of AgNPs and ionizing radiation on mitochondrial redox state and function in a panel of lung cell lines (A549, BEAS-2B, Calu-1 and NCI-H358). The exposure to AgNPs caused cell cycle arrest and decreased cell proliferation in A549, BEAS-2B and Calu-1, but not in NCI-H358. The mitochondrial reactive oxygen species (ROS) and protein oxidation increased in a time- and dose-dependent manner in the more sensitive cell lines with the AgNP exposure, but not in NCI-H358. While ionizing radiation also induced changes in the mitochondrial redox profiles, in general, these were not synergistic with the effects of AgNPs with the exception of NCI-H358 and only at a higher dose of radiation.