Frequent biphasic cellular responses of permanent fish cell cultures to deoxynilvalenol (DON)

Contamination of animal feed with mycotoxins is a major problem for fish feed mainly due to usage ofcontaminated ingredients for production and inappropriate storage of feed. The use of cereals for fish foodproduction further increases the risk of a potential contamination. Potential contaminants include themycotoxin deoxynivalenol (DON) which is synthesized by globally distributed fungi of the genus Fusarium.The toxicity of DON is well recognized in mammals. In this study, we confirm cytotoxic effects of DON inestablished permanent fish cell lines. We demonstrate that DON is capable of influencing the metabolicactivity and cell viability in fish cells as determined by different assays to indicate possible cellular targets ofthis toxin. Evaluation of cell viability by measurement of membrane integrity, mitochondrial activity andlysosomal function after 24 h of exposure of fish cell lines to DON at a concentration range of 0–3000 ng ml−1shows a biphasic effect on cells although differences in sensitivity occur. The cell lines derived from rainbowtrout are particularly sensitive to DON. The focus of this study lies, furthermore, on the effects of DON atdifferent concentrations on production of reactive oxygen species (ROS) in the different fish cell lines. Theresults show that DON mainly reduces ROS production in all cell lines that were used. Thus, our comparativeinvestigations reveal that the fish cell lines show distinct species-related endpoint sensitivities that alsodepend on the type of tissue from which the cells were derived and the severity of exposure.