Brain acetylcholinesterase of three perciformes: From the characterization to the in vitro effect of metal ions and pesticides

• Published in: Ecotoxicology and environmental safety Vol. 173; pp. 494 - 503
• Main Authors: Lopes, Danilo Francisco Corrêa, Assis, Caio Rodrigo Dias de, Sant’Anna, Mikele Cândida Sousa de, Silva, Janilson Felix da, Bezerra, Ranilson de Souza, Frédou, Flávia Lucena
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier Inc 30.05.2019
• Subjects: Acetylcholinesterase; Acetylcholinesterase - metabolism; Animals; Arsenic - toxicity; Biomarkers; Brain - drug effects; Brain - enzymology; Carbamates - toxicity; Cholinesterase Inhibitors - toxicity; Dichlorvos - toxicity; Fish; Fish Proteins - metabolism; Kinetics; Metal ions; Metals, Heavy - toxicity; Perciformes - metabolism; Pesticides; Pesticides - toxicity; Water Pollutants, Chemical - toxicity; Biomarkers; Fish; Acetylcholinesterase; Pesticides; Metal ions
• ISSN: 0147-6513; 1090-2414
• DOI: 10.1016/j.ecoenv.2019.02.047

Estuarine environments gather pollution from large regions including urban and industrial zones. The monitoring of environmental quality in these areas constitutes a real requirement for global sustainable development. Therefore, the aim of this study was to characterize the physicochemical and kinetic parameters of brain acetylcholinesterase (AChE) in the species Centropomus undecimalis, Diapterus auratus and Diapterus rhombeus and to assess the effects (in vitro) of pesticides and metal ions on their respective activities in order to investigate them as potential biomarkers. Physicochemical properties such as thermostability, optimal pH and temperature, as well as kinetic parameters were investigated. AChE was pointed as the predominant cholinesterase (ChE) in the brains of the species under study. The highest optimum pH value was observed for C. undecimalis (8.0), and the lowest for D. rhombeus and D. auratus, with 7.2 and 7.0, respectively. The optimal temperature was 35 °C for the three species. The AChEs of the three species presented moderate thermostability, since they retained 61%, 72% and 67% of the activity up to 45 °C (C. undecimalis, D. auratus and D. rhombeus, respectively). The carbamate carbofuran showed to be the strongest inhibitor even at very low concentrations (IC50: 0.182, 0.174 and 0.203 μmol/L - C. undecimalis, D. auratus and D. rhombeus, respectively), followed by dichlorvos and carbaryl. According to the findings, the AChE of these species may be proposed as in vitro biomarker of exposure to carbofuran and dichlorvos (all three species) and carbaryl (D. auratus and D. Rhombeus), as well as for exceeding limit concentrations of Hg2+ (D. rhombeus) and As3+ (D. auratus) in biomonitoring programs located or not at estuarine environments. •Brain AChEs from three estuarine Perciformes were physicochemical and kinetically characterized.•The species were selected from three different trophic guilds comprising different options of biomonitoring.•The enzymes were exposed to organophosphorus, carbamate pesticides and metal ions.•Inhibition of AChE by carbofuran occurred in concentrations below the USEPA Drinking Water Standards.•The enzymes may be promising biomarkers of carbofuran, carbaryl and dichlorvos exposure as well as of Hg2+ and As3+.