Activity of antioxidant defense enzymes in the Mediterranean Sea shrimp (Parapenaeus longirostris): relation to the presence of PCBs and PAHs in the south Adriatic Sea

Abstract

Background and Purpose: In order to assess exposure to effects of environmental pollutants on aquatic oiganisms, several different biochemical and physiological parameters were studied. The activity of antioxidant defense enzymes was measured in the Mediterranean Sea shrimp (Parapenaeus longirostris) and compared with the presence of polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs) in their sea water environment. Materials and Methods: The activity of the antioxidant defence enzymes superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and glutathione reductase (GR), as well as glutathione-S transferase (GST) as a phase II detoxification enzyme, was measured in the abdominal muscle of the shrimp in winter and spring at four different locations in the Montenegrine costal region of the Adriatic Sea. The results were correlated to the presence of PCBs and PAHs in the sea water at the time of sampling. Results and Conclusions: There was no obvious direct correlation between antioxidant defense activity and the presence and concentration of PCBs and PAHs in the sea water: The activities of SOD, GSH-Px and GR showed seasonal changes and therefore seasonality should be incorporated into the interpretation of antioxidant changes in future biomonitoring studies. Generally, SOD and GR activities were lower and GSH-Px was higher in winter when compared to spring. However these effects were not uniform and statistical trends were influenced by local environment. There were no seasonal changes in GST activity, but it's activity varied depending on the location, but without correlation to the presence of PCBs and PAHs.