title: Gene expression and biochemical responses in brain of zebrafish Danio rerio exposed to organic nanomaterials: carbon nanotubes (SWCNT) and fullerenol (C60(OH)18-22(OK4)).
abstract: Nanomaterials (NM) industry had grown in the last decade, although there are few studies concerning its potential toxicity effects on aquatic organisms. In this study the freshwater zebrafish (Danio rerio) was exposed to two kinds of carbon NM, single-wall carbon nanotubes (SWCNT) and fullerenol [C60(OH)18-22(OK4)] to analyze oxidative stress responses on fish brain. Adult zebrafish (mean mass: 0.52±0.01g) were submitted to intraperitoneal injections of SWCNT suspension and fullerenol solution (30mg/kg of fish), receiving one or two doses with a time interval of 24h. Results showed that total antioxidant capacity was lowered in brains of fish exposed 24h to fullerenol when compared to those from SWCNT treatment (p<0.05). After 48h, fullerenol induced higher expression of both catalytic and regulatory subunits of enzyme glutamate cysteine ligase when compared to control group (p<0.05), indicating an antioxidant behavior. In vitro assays showed a dual effect of SWCNT, since a pro-oxidant behavior was observed at low concentrations (0.1 and 1.0mg/L) and an antioxidant one at the highest concentration (10.0mg/L). Few biological responses were altered by this NM: decrease in total antioxidant capacity and induction of the expression of the transcription factor Nrf2 when compared to control group.
authors.affiliation: Instituto de Ciências Biológicas (ICB) - Universidade Federal do Rio Grande-FURG, RS, Brazil.
authors.forename: Alessandra Martins
authors.initials: AM
authors.lastname: da Rocha
authors.forename: Josencler Ribas
authors.initials: JR
authors.lastname: Ferreira
authors.forename: Daniela Marti
authors.initials: DM
authors.lastname: Barros
authors.forename: Talita Carneiro Brandão
authors.initials: TC
authors.lastname: Pereira
authors.forename: Mauricio Reis
authors.initials: MR
authors.lastname: Bogo
authors.forename: Sérgio
authors.initials: S
authors.lastname: Oliveira
authors.forename: Viviany
authors.initials: V
authors.lastname: Geraldo
authors.forename: Rodrigo Gribel
authors.initials: RG
authors.lastname: Lacerda
authors.forename: André Santarosa
authors.initials: AS
authors.lastname: Ferlauto
authors.forename: Luiz Orlando
authors.initials: LO
authors.lastname: Ladeira
authors.forename: Mauricio Veloso Brant
authors.initials: MV
authors.lastname: Pinheiro
authors.forename: José Maria
authors.initials: JM
authors.lastname: Monserrat
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000378:metabolism*; D001921:Brain / Q000187:drug effects*; D020134:Catalytic Domain; D037741:Fullerenes / Q000008:administration & dosage* / Q000633:toxicity; D005786:Gene Expression Regulation / Q000187:drug effects; D005721:Glutamate-Cysteine Ligase / Q000378:metabolism; D051267:NF-E2-Related Factor 2 / Q000096:biosynthesis; D037742:Nanotubes, Carbon / Q000737:chemistry*; D018384:Oxidative Stress; D017382:Reactive Oxygen Species; D015027:Zebrafish / Q000235:genetics / Q000378:metabolism; D029961:Zebrafish Proteins / Q000096:biosynthesis
chemical_list: D000975:Antioxidants; D037741:Fullerenes; D051267:NF-E2-Related Factor 2; D037742:Nanotubes, Carbon; D017382:Reactive Oxygen Species; D029961:Zebrafish Proteins; C495638:nfe2l2a protein, zebrafish; C108127:fullerenol; D005721:Glutamate-Cysteine Ligase