Effects of mercury on glutathione and glutathione-dependent enzymes in hares (Lepus europaeus Pallas)

Abstract

The aim of this study was to analyze and evaluate risks of long-term exposure to mercury in hares (Lepus europaeus Pallas), with a chemical-analytical approach evaluating median mass fraction of toxic mercury in the hares organs (liver, kidney, muscle and brain). To obtain better insight into possible effects of mercury, the study included screening of the oxidative status after long term exposure to low concentrations of mercury. Hares organs were analyzed for total mercury concentration by AAS. Glutathione and glutathione-dependent enzymes status was also investigated. The median mercury concentrations (wet weight) in the liver, kidney, muscle and brain of the hares ranged from 0.058–0.189, 0.138–0.406, 0.013–0.046 and 0.022–0.102 μg/g respectively. Concentration of the glutathione (GSH), glutathione-peroxidase (GPx), and glutathione-reductase (GR) activity increased with the mercury concentration. However, glutathione S-transferase (GST) and superoxide-dismutase (SOD) activity decreased with the mercury concentration. The results of this study show the impact of environmentally absorbed mercury on the antioxidant status of the examined hares. Further research on long-term exposure to low concentrations of mercury is needed.

Keywords:

• Mercury
• enzymes
• oxidative stress
• hares

Acknowledgments

This work was supported by a grant from the Croatian Ministry of Science (Project Nos. 053-0532400-2362 and 062-0621341-0061) and from the Program of the European Community for Research and Technological Development (Project No. FOOD-CT-2006-016253).