Assessment of cultured fish hepatocytes for studying cellular uptake and (eco)toxicity of nanoparticles

Abstract
Environmental context. The production and application of engineered nanoparticles is rapidly increasing, and development of suitable models for screening nanoparticles for possible toxic effects is essential to protect aquatic organisms and support the sustainable development of the nanotechnology industry. Here, the suitability of isolated rainbow trout hepatocytes was assessed for high through-put toxicity screening of nanoparticles and for studying uptake of nanoparticles into cells. Relatively little is known regarding the fate and possible toxic effects of engineered nanoparticles (ENPs) in the aquatic environment. We assessed the suitability of isolated trout hepatocytes for high throughput toxicity screening of ENPs, exposing them to a variety of metal and metal oxide nanoparticles and their bulk counterparts. We found no effects of the ENPs on cell viability, or on lipid peroxidation, with the exception of exposure to ZnO nanoparticles, or on glutathione-S-transferase (GST) levels, for exposure concentrations up to 500 μg mL–1. All ENPs, however, were internalised in the cultured hepatocytes, as shown by coherent anti-Stokes Raman scattering (CARS) as an imaging technique. Our findings suggest that fish hepatocyte cultures are suitable for studies investigating the cellular uptake of ENPs, but they do not appear to be sensitive to ENP exposure and thus not a good in vitro model for nanoparticle toxicity screening.