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São Paulo, Brazil

Dos Santos D.R.,Federal University of Parana | Yamamoto F.Y.,Federal University of Parana | Filipak Neto F.,Federal University of Parana | Randi M.A.F.,Federal University of Parana | And 6 more authors.
Environmental Science and Pollution Research | Year: 2016

The knowledge concerning associations between chronic chemical exposure and many disorders with complex etiology involving gene–environment interactions is increasing, and new methods must be developed to improve water quality monitoring. The complexity of chemical mixtures in polluted aquatic environments makes the evaluation of toxic potential in those sites difficult, but the use of biomarkers and bioindicators has been recognized as a reliable tool to assess risk of exposure to biota and also the human population. In order to evaluate the use of fish and biomarkers to assess toxic potential and bioavailability of chemicals in human-related hydric resources, an in situ experiment was accomplished in two water reservoirs designated for human supply, which were previously evaluated by the local environmental regulatory agency through a set of physical, chemical, and classical biological parameters. Molecular, biochemical, and morphological biomarkers were performed in caged Oreochromis niloticus kept for 6 months in the studied reservoirs to assess potentially useful biomarkers to evaluate the quality of water for human supply. Chemical analysis of toxic metals in liver and muscle and polycyclic aromatic hydrocarbons (PAHs) in bile was considered to assess the bioavailability of pollutants and highlight human activity impact. The reservoir previously classified by a governmental agency as less impacted presented more risk of exposure to biota. These results were supported by chemical analysis, vitellogenin expression, histopathological findings (gonads, liver, and gills), as well as indicators of neurotoxic effects and oxidative stress in liver. The inclusion of some biomarkers as parameters in regulatory monitoring programs in reservoirs designated for human supply is strongly suggested to evaluate the risks of exposure to the human population. Thus, a revision of the traditional biological and physicochemical analysis utilized to establish the conditions of water quality is necessary. © 2016 Springer-Verlag Berlin Heidelberg

Moura Costa D.D.,Federal University of Parana | Bozza D.A.,Federal University of Parana | Rizzo L.E.,Federal University of Parana | Garcia J.,Estacao de Piscicultura Panama | And 2 more authors.
Fish Physiology and Biochemistry | Year: 2016

Endocrine-disrupting chemicals (EDCs) are widespread used and can interfere on hormone regulation with adverse consequences for both biota and human. Vitellogenin (vtg) is a yolk precursor protein synthesized by the liver in response to estrogen. In order to characterize the vtg of tropical fish Rhamdia quelen and establish a molecular biomarker, adult male individuals were exposed to 17-β-estradiol (E2) for vtg induction and anti-R. quelen vtg polyclonal antibodies production. Vitellogenic female fish were used as positive control group. E2-induced vtg was characterized as a glycolipophosphoprotein of high molecular mass with peptide mass fingerprint very similar in E2-exposed male and vitellogenic female fish. A polyclonal serum containing anti-R. quelen vtg antibodies was produced and showed high specificity and sensibility to detect the vtg of three fish species: R. quelen, Piaractus mesopotamicus and Prochilodus lineatus. Wildlife and laboratory studies reported that EDCs released into the environment may alter the levels of plasma vtg in male fish, making this protein a valuable biomarker of xenoestrogens exposure. Then, we propose the use of anti-R. quelen vtg as a tool for biomonitoring studies and water quality assessment in Brazil and South American countries where the three fish species occur. © 2016 Springer Science+Business Media Dordrecht

Oliveira H.H.P.,Federal University of Parana | Liebel S.,Federal University of Parana | Rossi S.C.,Federal University of Parana | Azevedo A.C.B.,Federal University of Parana | And 6 more authors.
Ecotoxicology and Environmental Safety | Year: 2015

The effects of benzo(a)pyrene (BaP), dichlorodiphenyltrichloroethane (DDT) and tributyltin (TBT) association were investigated through a multi-biomarker approach. Ten Rhamdia quelen fish per group were exposed through intraperitoneal injections either to BaP (0.3; 3 or 30mgkg-1), DDT or TBT (0.03; 0.3 or 3mgkg-1) or BaP/DDT, BaP/TBT, DDT/TBT or BaP/DDT/TBT on their lowest doses. The experiments were divided in acute (one dose, 5-day) and sub-chronic (3 doses, 15-day). Control groups received an equal volume of PBS or canola oil (1mlkg-1). The three tested contaminants altered AChE activity in brain and muscle in similar ways; the mixtures antagonized the increase evoked by the contaminants alone. BaP and TBT increased GSH content and mixtures reduced it. GPx activity was increased by DDT and TBT in the 15-day experiment and reduced by the mixtures. BaP increased GST activity in sub-chronic experiment while TBT reduced it in the acute experiment. BaP/TBT increased GST activity compared to all groups; the other mixtures reduced it compared to BaP or DDT in the 5-day experiment. BaP, DDT and TBT increased δ-ALAd activity mainly in acute exposure; the mixtures also increased δ-ALAd compared to DDT or TBT in 5 and 15-day. BaP, TBT and BaP/DDT decreased LPO in the acute experiment. In the sub-chronic experiment DDT/TBT increased LPO when compared to TBT. None of the contaminants alone altered PCO, but all mixtures increased it compared to one or another contaminant. Contaminants isolated had a more acute effect in ALT plasma level; their lowest dose, which had no effect alone, in combination has led to an increase of this enzyme, especially after 15 days. DDT increased AST in the acute and sub-chronic experiments, while TBT did the same in the latter. DDT/TBT decreased AST opposing the effect of the contaminants alone in the 5-day experiment. Hepatic lesions index could be explained by a more acute effect of the contaminants alone or combined and by activation of cell defenses after the sub-chronic exposure. TBT increased melanomacrophages counting in the 5-day experiment and the mixtures increased it in the 5 and 15-day experiments. Overall, the majority of the biomarkers pointed to a more toxic effect when these contaminants were combined, leading to unexpected toxicities compared to individual exposure scenarios. These findings are relevant considering environmental exposure conditions, since organisms are often exposed to different combinations of contaminants. © 2015 Elsevier Inc.

Costa D.D.M.,Federal University of Parana | Neto F.F.,Federal University of Parana | Costa M.D.M.,Federal University of Parana | Morais R.N.,Federal University of Parana | And 3 more authors.
Comparative Biochemistry and Physiology - C Toxicology and Pharmacology | Year: 2010

This study investigated the effects of different doses of 17-β-estradiol (E2) in Rhamdia quelen. Groups of males exposed to different doses of E2 (0.1 mg kg- 1, 1 mg kg- 1 and 10 mg kg- 1) were compared with non-exposed male and female fish groups. Among the considered biomarkers, no significant differences were observed for micronuclei test, reduced glutathione concentration and lipid peroxidation. All E2-treated individuals had decreased glutathione S-transferase activity. Increased catalase and superoxide dismutase activities, increased vitellogenin expression and decreased metallothionein concentration were observed in males treated with the highest dose. Liver of all test groups showed necrotic areas, but cytoplasm vacuolization was again found only in the individuals exposed to highest dose. E2 causes deleterious hepatic effects to R. quelen, and vitellogenin expression, catalase and superoxide dismutase activity and metallothionein concentration represent appropriate biomarkers for studying E2 effects. Additionally, the response of some biomarkers was similar in males exposed to E2 and unexposed females, and therefore exposure to endocrine disruptors may cause consequences for fish populations. © 2009 Elsevier B.V. All rights reserved.

Oliveira H.H.P.,Federal University of Parana | Babin M.,Institute des Sciences de la Mer de Rimouski | Garcia J.R.E.,Estacao de Piscicultura Panama | Filipak Neto F.,Federal University of Parana | And 3 more authors.
Ecotoxicology and Environmental Safety | Year: 2013

In an attempt to explore complex metabolic interactions between toxicants present in polluted freshwater, hepatic metabolism of benzo(a)pyrene (BaP) and tributyltin (TBT) in fish was investigated when these compounds were administrated alone, mixed together and along with dichlorodiphenyltrichloroethane (DDT). Ten Rhamdia quelen per group were treated with a single intra-peritoneal (IP) dose (5-day experiment) or three successive doses (15-day experiment) either containing BaP (0.3; 3 or 30mgkg-1) or TBT (0.03; 0.3 or 3mgkg-1) or a combination of BaP+TBT, BaP+DDT, TBT+DDT and BaP+TBT+DDT under their respective lower doses, with DDT dose kept at 0.03mgkg-1. Tetrahydroxy-benzo(a)pyrene (BaP-tetrol-I), and dibutyltin (DBT) and monobutyltin (MBT) were analyzed to assess BaP and TBT hepatic metabolism, respectively. A significant difference in BaP-tetrol-I concentration was observed in liver and bile between the lowest and the highest doses of BaP in both 5 and 15-day experiments. In the 15-day experiment, the presence of TBT with BaP reduced the amount of BaP-tetrol-I in bile compared to the BaP alone. The time of exposure and the number of doses affected BaP-tetrol-I concentration in the bile of fish exposed to BaP 0.3mgkg-1 and BaP+DDT. TBT and its metabolites concentrations showed a dose-dependent increase in the liver in both experiments and in the bile in the 5-day experiment. TBT at its lowest dose was completely metabolized into DBT and MBT in the liver in the 15-day experiment. No TBT metabolites were detected in the bile of fish exposed to the mixtures in the 5-day experiment, except for a small MBT amount found in BaP+TBT+DDT. This study strengthens the hypothesis of a metabolic interaction between BaP and TBT in fish and suggests DDT as an important third player when present in the mixture. © 2013 Elsevier Inc.

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