Bioaccumulation, behavior changes and physiological disruptions with gender-dependent in lizards (Eremias argus) after exposure to glufosinate-ammonium and l-glufosinate-ammonium

Abstract

Reptiles, the most diverse taxon of terrestrial vertebrates, might be particularly vulnerable to soil pollution. Reptiles especially lizards have been rarely evaluated in ecotoxicological studies, and there is a very limited report for effects of soil pesticide contaminants on lizards. In this study, male and female lizards (Eremias argus) were exposed to Glufosinate-ammonium (GLA) and l- Glufosinate-ammonium (L-GLA) for 60 days. Slower sprint speed, higher frequency of turning back and reduced brain index were observed in treatment groups. The accumulation of GLA in the brain of lizard was higher than that of L-GLA. Moreover, the activities of neurotoxicity-related enzymes and biomarkers of oxidative stress were also investigated. In summary, the neurotoxic effects of lizards have been observed after exposure to GLA and L-GLA. Based on the result of the Integrated Biomarker Response (IBR), males were more sensitive to contaminants than females. On the other hand, the neurotoxic pathways by GLA and L-GLA triggered were slightly different: GLA mainly acted on glutamine synthetase (GS), acetylcholinesterase (AchE) and Catalase (CAT) and L-GLA aimed at AchE, Na+/K+-ATPase, Superoxide dismutase (SOD) and Malondialdehyde (MDA). In summary, the accumulation of GLA and L-GLA in lizard's brain induced neurotoxicity by altering the levels of enzymes related to nervous system and antioxidant activity and further resulted in the decrease of brain index and locomotor performance.