An integrated approach for assessing the in vitro and in vivo redox-related effects of nanomaterials.

Over the last few decades, nanotechnology has risen to the forefront of both the research and industrial interest, resulting in the manufacture and utilization of various nanomaterials and in their integration into a wide range of fields. However, the consequent elevated exposure to nanomaterials raises serious concerns regarding their effects on human health and safety. Existing scientific data indicate that the induction of oxidative stress, through the excessive generation of Reactive Oxygen Species (ROS), might be the principal mechanism of exerting their toxicity. Meanwhile, various nanomaterials exhibit antioxidant properties, either intrinsic or resulting from their functionalization with conventional antioxidants. Since their redox properties are implicated in the manifestation of their biological effects, we propose an integrated approach for the assessment of the redox-related activities of nanomaterials at three biological levels (in vitro-cell free systems, cell cultures, in vivo). Towards this direction, a battery of translational biomarkers is recommended, and the most reliable protocols in our opinion are presented in detail. The aim of the present approach is to acquire a better understanding concerning the biological actions of nanomaterials in the interrelated fields of redox biology and toxicology.