Modulatory role of copper on β-naphthoflavone-induced DNA damage in European eel (Anguilla anguilla L.)

Gill and kidney DNA integrity (alkaline unwinding assay) was assessed in Anguilla anguilla exposed for 24-h to copper (Cu: 1 or 2.5 mu M), with or without 24-h pre-exposure to a polycyclic aromatic hydrocarbon (PAH)-like compound-beta-naphthoflavone (BNF: 2.7 mu M). Gill showed DNA integrity loss in all the exposure conditions, reflecting a dual mode of BNF-Cu interaction depending on the metal concentration. Thus, antagonistic or additive effects were observed for BNF + Cu 1 mu M or BNF + Cu 2.5 mu M, respectively. Kidney showed decreased DNA integrity for single exposures (BNF, Cu 1 mu M), whereas sequential exposures displayed higher DNA integrity than BNF alone, revealing a Cu antagonistic effect at both the concentrations. The results also demonstrated that (i) both organs are receptive For Cu inhibitory role against BNF genotoxicity; (ii) kidney is more resistant to Cu individual exposures; and (iii) under multipollution conditions genotoxicity cannot be predicted on the basis of individual chemicals responses. (C) 2008 Elsevier Inc. All rights reserved.