Effects of Beta-Naphthoflavone and 3-Methylcholantheren on Biochemical Markers in Sturgeon Fish, Huso huso

Polycyclic aromatic hydrocarbons (PAHs) are a predominant group of contaminants that have been shown to accumulate and persist in marine organisms. We evaluated the dose-dependent induction of the cytochrome P4501A (CYP1A) system in the Sturgeon fish, Huso huso after after exposure to PAHs, beta-naphthoflavone (BNF) and 3- methylcholantheren.

The fish were treated by i.p. injections of beta–naphthoflavone and 3- methylcholantheren dissolved in corn oil at three doses 35, 70 and 105 mg/kg wet-body weight respectively for 72 h every day. Similarly, the control fish received injections of only corn oil. Microsomal fraction was prepared and ethoxy resorufin-O-deethylase activity (EROD) was measured in the fish liver. Cytochrome P4501A1 (CYP1A1) content was estimated by ELISA based on monoclonal anti-cod P4501A1.

Beta-naphthoflovone and 3-methylcholantheren treated-fish developed 15-32 fold increase in Ethoxyresorufin-O-deethylase activity in liver microsomes. The results of ELISA showed higher levels of cytochrome P4501A content in treated fish as compared to controls.

A parallel increase of the CYP1A immunochemically assay and an increase in EROD activity could be recorded for beta –naphthoflavone and 3- methylcholantheren in injected fish. Dose-response relationships on the induction of EROD and CYP1A immunodetectable protein were recorded. Therefore, EROD activity and CYP1A content can be used as a biomarker of polycyclic aromatic hydrocarbons.