Embriotoxicity and neurotoxic effects on Danio rerio produced by the water of a Cutzamala reservoir: Villa Victoria dam

Abstract

The Cutzamala system is made up of several storage dams, one of them is the Villa Victoria Dam which, over time, has presented problems such as deforestation for agriculture, high demand for water, droughts, decline in aquatic population and water pollution. Due to this, the aim of this work was to evaluate the embryotoxicity and neurotoxic effects in Danio rerio produced by the water of this reservoir. Embryotoxicity was determined through the general morphological score, teratogenic index and % mortality. Oxidative damage was identified by the antioxidant enzymes activity and the degree of carbonylated protein content and lipoperoxidation in the larvae. Neurotoxic effects were assessed through acetylcholinesterase activity and ache and nrxn1 gene expression, in addition to behavioral changes in the larvae through basal locomotor activity, visual motor response, and thigmotaxis. A reduction in embryonic development, teratogenic alterations and a high percentage of embryo mortality were observed. Likewise, changes in the activity of antioxidant enzymes, as well as lipoperoxidation and carbonylated proteins, were identified. Finally, an increase in the enzymatic activity of acetylcholinesterase and overexpression of ache and nrxn1 was observed, which resulted in the reduction of basal locomotor activity, visual motor response and negative thigmotaxis in D. rerio larvae. These results demonstrate the effects of contamination in the Villa Victoria Dam and the risk that this and other problems affect the water quality of the reservoir.