Determination of toxic effects of aluminium oxide and nickel nanoparticles on genetic structure of zebrafish (Danio rerio) larvae

Engineered nanoparticles can potentially generate adverse effects on tissue, organ, cellular, subcellular, DNA, and protein levels due to their unique physico-chemical properties. To date it is not yet completely understood, whether effects of nanoparticles are solely or partly due to dissolved ions. In the present study, it was investigated the potential toxic effects of aluminium oxide (Al2O3), and nickel (Ni) nanoparticles and their dissolved ions on larval (72 h post fertilization) zebrafish (Danio rerio) by analysing changes in expression levels of stress-related genes (p53, rad51, and mt2) by real-time quantitative PCR (RT-qPCR). Another objective was to assess genotoxicity of these two nanoparticles by Comet Assay technic. The lethal concentrations for 50% mortality (LC50) in larval zebrafish exposed (96 h) to 0-500 mg/L Al2O3 nanoparticles and 0-300 mg/L Ni nanoparticles were 130.19 ± 5.59 mg/L and 122.22 ± 6.33 mg/L, respectively. A concentration-dependent increase in DNA strand breaks was detected in blood cells from larvae exposed (96 h) to these two nanoparticles. DNA damages were determined as %21,82 for Al2O3 nanoparticles and %26,87 for Ni nanoparticles exposed larvae. Induction of stress-related genes in larvae was complex and not directly related to nanoparticle concentrations, although there was no significant difference in rad51 and p53 gene expression changes, there was statistically significant increase in mt2 gene expression of larvae exposed to nanoparticles relative to controls.