Effects of the acute exposition to glyphosate-based herbicide on oxidative stress parameters and antioxidant responses in a hybrid Amazon fish surubim (Pseudoplatystoma sp) Valéria Dornelles Gindri Sinhorin a , Adilson Paulo Sinhorin a , Jhonnes Marcos dos Santos Teixeira b , Kelly Márcia Lazarotto Miléski b , Paula Carine Hansen b , Paula Sueli Andrade Moreira c , Nair Honda Kawashita d , Amanda Martins Baviera e , Vania Lúcia Loro f,n a Instituto de Ciências Naturais, Humanas e Sociais/Laboratórios Integrados de Pesquisas Químicas, Universidade Federal de Mato Grosso (UFMT), Câmpus de Sinop, MT, Brazil b Instituto de Ciências da Saúde, Universidade Federal de Mato Grosso (UFMT), Câmpus de Sinop, MT, Brazil C Instituto de Ciências Agrárias e Ambientais, Universidade Federal de Mato Grosso (UFMT), Câmpus de Sinop, MT, Brazil d Instituto de Ciências Exatas e da Terra, UFMT, Câmpus de Cuiabá, MT, Brazil e Departamento de Análises Clínicas, Faculdade de Ciências Farmacêuticas, Universidade Estadual Paulista (UNESP), Campus de Araraquara, SP, Brazil f Laboratório de Bioquímica Adaptativa e Toxicologia de Peixes, Universidade Federal de Santa Maria (UFSM), Santa Maria, RS, Brazil article info Article history: Received 26 December 2013 Received in revised form 23 April 2014 Accepted 25 April 2014 Keywords: Fish farmers Hybrid Amazon fish Pesticide Oxidative stress Soybean monoculture Roundup abstract The aim of this study was to investigate the effects of acute glyphosate (active ingredient) exposure on the oxidative stress biomarkers and antioxidant defenses of a hybrid surubim (Pseudoplatystoma sp). The fish were exposed to different herbicide concentrations for 96 h. The thiobarbituric acid-reactive substances (TBARS), protein carbonyls and antioxidant responses were verified. The 15 mg a.p L À1 of herbicide resulted in the death of 50% of the fish after 96 h. An increase in liver and muscle TBARS levels was observed when fish were exposed to the herbicide. The protein carbonyl content was also increased in the liver (4.5 mg a.p L À1 concentration) and brain (2.25 mg a.p L À1 concentration). The antioxidant activities decreased in the liver and brain after exposure to herbicide. Levels of ascorbic acid in the liver (2.25 mg a.p L À1 and 4.5 mg a.p L À1 concentrations) and brain (2.25 mg a.p L À1 concentration) were increased post-treatment. Levels of total thiols were increased in the liver and brain (2.25 mg L À1 and 7.5 mg a.p L À1 , respectively). Glyphosate exposure, at the tested concentrations affects surubim health by promoting changes that can affect their survival in natural environment. Some parameters as TBARS and protein carbonyl could be early biomarkers for Roundup exposure in this fish species. & 2014 Elsevier Inc. All rights reserved. 1. Introduction In recent years the frequent use of agricultural pesticides has been cited as one of the factors contributing to environmental contamination. Hundreds of pesticides of varying chemical struc- tures are extensively used to control a wide variety of agricultural pests and can contaminate aquatic habitats due to leaching and water runoff from treated areas. These pesticides may result in an immense disruption of the ecological balance causing widespread damage to non-target organisms, including fish of commercial importance (Oruç et al., 2004). Pesticide exposure can cause an increase in the production of reactive oxygen species (ROS) and also alter the antioxidant defenses. ROS are highly reactive substances that cause damage to lipids, proteins, carbohydrates, and nucleic acids (Monserrat et al., 2007). The oxidative damage involves the peroxidation of unsaturated fatty acids and the corresponding increase in tissue malondialdehyde levels, which serve as an indicator of possible damage to lipids. The reactive species may also cause damage to proteins, which is frequently measured by protein carbonyl levels. Protein carbonyl formation is a result of protein oxidation that can lead to the loss of sulfhydryl groups in addition to the modification of amino acids, ultimately contributing to the formation of carbonyls and other oxidized moieties (Parvez and Raisuddin, 2005). Some authors considered that both the levels of lipid peroxidation (LPO) and protein carbonyls have been used as biomarkers for fish species exposed to pesticides (Menezes et al., Contents lists available at ScienceDirect journal homepage: www.elsevier.com/locate/ecoenv Ecotoxicology and Environmental Safety http://dx.doi.org/10.1016/j.ecoenv.2014.04.040 0147-6513/& 2014 Elsevier Inc. All rights reserved. n Corresponding author. Fax: þ55 55 3220 8240. E-mail address: vania.loro@gmail.com (V.L. Loro). Ecotoxicology and Environmental Safety 106 (2014) 181–187