Seasonal changes in oxidative stress biomarkers of the snail Viviparus acerosus from the Velika Morava River, Serbia

The river snail (Viviparus acerosus) from the Velika Morava River, Serbia was chosen in our study in order to determine seasonal changes in oxidative stress biomarkers between July (summer) and September (autumn). The activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px), glutathione reductase (GR) and the phase II biotransformation enzyme glutathione-S-transferase (GST), as well as the concentration of total glutathione (GSH), were examined in the whole body of the river snails. The obtained results show significantly higher activities of CAT, GSH-Px, GR and biotransformation phase II enzyme GST in September compared to July, while the GSH concentration was lower. There was no general trend in the seasonal changes in the activity of SOD. The presented data show that animals in their natural environment are exposed to constant fluctuations of environmental conditions that could cause antioxidants to exhibit seasonal variations. This fact should be considered as an important variable in the interpretation of results in biomonitoring studies. [Acknowledgments. This study was supported by the Ministry of Education and Science of the Republic of Serbia, Grants Nos. 173041 and 173025