title: Acute selenium selenite exposure effects on oxidative stress biomarkers and essential metals and trace-elements in the model organism zebrafish (Danio rerio).
abstract: Selenium (Se) is an essential trace-element that becomes toxic when present at high concentrations. Little is known regarding Se effects on parameters such as oxidative stress biomarkers. The aim of the present study was to investigate the effects of acute selenium exposure on oxidative stress biomarkers in a model organism, zebrafish (Danio rerio). Fish were exposed to selenium selenite at 1mgL(-1). Reduced glutathione (GSH), and metallothionein (MT) concentrations were determined in liver, kidney and brain, with MT also being determined in bile. Essential metals and trace-elements were also determined by inductively coupled mass spectrometry (ICP-MS) in order to verify possible metal homeostasis alterations. GSH concentrations in liver, kidney and brain increased significantly (1.05±0.03μmolg(-1) ww, 1.42±0.03μmolg(-1) ww and 1.64±0.03μmolg(-1) ww, respectively) in the Se-exposed group when compared to the controls (0.88±0.05μmolg(-1) ww, 0.80±0.04μmolg(-1) ww and 0.89±0.03μmolg(-1) ww for liver, kidney and brain, respectively). MT levels in Se-exposed liver (0.52±0.03μmolg(-1) ww) decreased significantly in comparison to the control group (0.64±0.02μmolg(-1) ww), while levels in bile increased, albeit non-significantly. This is in accordance with previous studies that indicate efficient biliary MT action, leading to a rapid metabolism and elimination of contaminants from the body. Levels in the brain increased significantly after Se-exposure (0.57±0.01μmolg(-1) ww) when compared to the control group (0.35±0.03μmolg(-1) ww) since this organ does not present a detoxification route as quick as the liver-gallbladder route. Several metal and trace-elements were altered with Se-exposure, indicating that excess of selenium results in metal dyshomeostasis. This is the first report on metal dyshomeostasis due to Se-exposure, which may be the first step in the mechanism of action of selenium toxicity, as is postulated to occur in certain major human pathophysiologies.
authors.affiliation: Pontifícia Universidade Católica-Rio de Janeiro (PUC-Rio), Chemistry Department, Rua Marquês de São Vicente, 225, Gávea, CEP, 22453-900 Rio de Janeiro, RJ, Brazil; Universidade Federal do Estado do Rio de Janeiro (UNIRIO), Programa de Pós-Graduação em Ciências Biológicas-Biodiversidade Neotropical, Av. Pasteur, 458-Urca, CEP, 22290-240 Rio de Janeiro, RJ, Brazil; Instituto de Química, Departamento de Química Analítica, Universidade Estadual de Campinas-UNICAMP, Grupo de Espectrometria, Preparo de amostras e Mecanização-GEPAM, Cx. Postal 6154, 13084-971Campinas, SP, Brazil. Electronic address: rachel.hauser.davis@gmail.com.
authors.forename: R A
authors.initials: RA
authors.lastname: Hauser-Davis
authors.affiliation: Universidade Federal do Estado do Rio de Janeiro (UNIRIO), Programa de Pós-Graduação em Ciências Biológicas-Biodiversidade Neotropical, Av. Pasteur, 458-Urca, CEP, 22290-240 Rio de Janeiro, RJ, Brazil.
authors.forename: J A N
authors.initials: JA
authors.lastname: Silva
authors.affiliation: Pontifícia Universidade Católica-Rio de Janeiro (PUC-Rio), Chemistry Department, Rua Marquês de São Vicente, 225, Gávea, CEP, 22453-900 Rio de Janeiro, RJ, Brazil.
authors.forename: Rafael C C
authors.initials: RC
authors.lastname: Rocha
authors.affiliation: Pontifícia Universidade Católica-Rio de Janeiro (PUC-Rio), Chemistry Department, Rua Marquês de São Vicente, 225, Gávea, CEP, 22453-900 Rio de Janeiro, RJ, Brazil.
authors.forename: Tatiana
authors.initials: T
authors.lastname: Saint'Pierre
authors.affiliation: Universidade Federal do Estado do Rio de Janeiro (UNIRIO), Programa de Pós-Graduação em Ciências Biológicas-Biodiversidade Neotropical, Av. Pasteur, 458-Urca, CEP, 22290-240 Rio de Janeiro, RJ, Brazil.
authors.forename: R L
authors.initials: RL
authors.lastname: Ziolli
authors.affiliation: Instituto de Química, Departamento de Química Analítica, Universidade Estadual de Campinas-UNICAMP, Grupo de Espectrometria, Preparo de amostras e Mecanização-GEPAM, Cx. Postal 6154, 13084-971Campinas, SP, Brazil; Instituto Nacional de Ciência e Tecnologia em Bioanalítica-INCTBio, Instituto de Química, Universidade Estadual de Campinas-UNICAMP, Cx. Postal 6154, 13084-971 Campinas, SP, Brazil.
authors.forename: M A Z
authors.initials: MA
authors.lastname: Arruda
mesh_terms: D000818:Animals; D015415:Biomarkers / Q000378:metabolism*; D001921:Brain / Q000187:drug effects / Q000378:metabolism; D005978:Glutathione / Q000378:metabolism; D007668:Kidney / Q000187:drug effects / Q000378:metabolism; D008099:Liver / Q000187:drug effects / Q000378:metabolism; D008668:Metallothionein / Q000378:metabolism; D023421:Models, Animal; D009928:Organ Specificity / Q000187:drug effects; D018384:Oxidative Stress / Q000187:drug effects*; D020887:Selenious Acid / Q000494:pharmacology*; D012643:Selenium / Q000494:pharmacology*; D013054:Spectrophotometry, Atomic; D014131:Trace Elements / Q000378:metabolism*; D015027:Zebrafish / Q000378:metabolism*
chemical_list: D015415:Biomarkers; D014131:Trace Elements; D008668:Metallothionein; D020887:Selenious Acid; D005978:Glutathione; D012643:Selenium
keywords: GSH; Metal dyshomeostasis; Metallothionein; Oxidative stress; Selenium; Zebrafish