Do different diets affect oxidative stress biomarkers and metal bioaccumulation in two snake species?

• Published in: Comparative biochemistry and physiology. Toxicology & pharmacology 2019-09, Vol.223, p.26-34
• Main Authors: Gavrić, Jelena, Despotović, Svetlana, Prokić, Marko, Gavrilović, Branka, Radovanović, Tijana, Anđelković, Marko, Tomović, Ljiljana, Borković-Mitić, Slavica, Pavlović, Slađan, Saičić, Zorica
• Format: Article
• Language: English
• Subjects: Animal Nutritional Physiological Phenomena; Animals; Antioxidants - metabolism; Bioaccumulation; Biomarkers - metabolism; Colubridae - physiology; Enzymes - metabolism; Female; Gastrointestinal Contents; Heavy metals; Liver - drug effects; Liver - metabolism; Metals, Heavy - analysis; Metals, Heavy - pharmacokinetics; Metals, Heavy - toxicity; Muscle, Skeletal - drug effects; Muscle, Skeletal - metabolism; N. tessellata; Natrix natrix; Oxidative Stress; Oxidative stress biomarkers; Predatory Behavior; Serbia; Species Specificity; Water Pollutants, Chemical - analysis; Water Pollutants, Chemical - pharmacokinetics; Water Pollutants, Chemical - toxicity
• ISSN: 1532-0456; 1878-1659
• DOI: 10.1016/j.cbpc.2019.05.010

In this study we examined possible differences in heavy metal accumulation and oxidative stress parameters in the liver and muscle of two semi-aquatic snakes: grass snake (Natrix natrix) and dice snake (N. tessellata), that inhabit the same environment but differ in prey diversity. The obtained results revealed some interspecies, inter-tissue, prey-snake and prey-prey differences in heavy metal concentrations. Grass snakes pray contained significantly higher concentrations of Al, Cr and Fe as compared to food of dice snakes. Both investigated snakes accumulated generally lower concentrations of metals than their prey, indicating that they are not at risk of contaminant biomagnification. A significant interspecies difference in accumulation was observed only for Cu and Mn concentrations. On the other hand, analysis of oxidative stress biomarkers showed clear differences between the investigated snake species and the two investigated tissues. The liver of grass snake had increased superoxide dismutase, glutathione reductase and glutathione-S-transferase activities in comparison to dice snake. In muscle, a reverse trend was observed for the activities of these three enzymes, as well as for glutathione peroxidase activity. The higher number of significant correlations observed between oxidative stress biomarkers and heavy metal concentrations in grass snake points to upregulation of the antioxidative system (AOS), which resulted in a lower TBARS concentration. Results show that while the investigated snake species did not differ significantly in the accumulated metals, their defense mechanisms were different. This reveals the complexity of the AOS and points to the cooperation of different AOS components in individuals from natural populations. [Display omitted] •Examined snakes accumulated generally lower concentrations of metals than their prey.•Oxidative stress biomarkers showed clear differences between the investigated snakes.•Species-specific responses determined the patterns of antioxidative defense enzymes.•Dice snake may be less tolerant to pollution exposure.