title: Zinc alleviates mercury-induced oxidative stress in Pfaffia glomerata (Spreng.) Pedersen.
abstract: The possible role of zinc (Zn) to reverse the oxidative stress caused by mercury (Hg) was investigated in Pfaffia glomerata plantlets. Thirty-day-old acclimatized plantlets of P. glomerata were exposed to four treatments: control, 50 μM Zn, 50 μM Hg and 50 μM Zn + 50 μM Hg for 9 days. In Zn + Hg treatment, shoot and root Hg concentrations were 59 and 24% smaller than that plants exposed to 50 μM Hg added alone. An increase in the Zn concentration in the shoot of plants exposed to Zn + Hg occurred, although in the roots Zn concentration was not altered, when compared to the control. Fresh and dry weights, as well as the activity of δ-aminolevulinic acid dehydratase (δ-ALA-D) in Hg-treated plants were significantly reduced. Percentage survival, fresh and dry weights and δ-ALA-D activity of plants treated by 50 μM Zn + 50 μM Hg were greater than of that treated by Hg alone. Moreover, Zn treatment reduced the lipid peroxidation caused by Hg, being this effect related to increased root superoxide dismutase activity, and shoot catalase and ascorbate peroxidase activities. In conclusion, the presence of Zn in the substrate caused a significant reduction in the oxidative stress induced by Hg.
authors.affiliation: Departamento de Biologia, Centro de Ciências Naturais e Exatas, Universidade Federal de Santa Maria, Santa Maria, RS 97105-900, Brazil.
authors.forename: Nicéia Spanholi
authors.initials: NS
authors.lastname: Calgaroto
authors.forename: Denise
authors.initials: D
authors.lastname: Cargnelutti
authors.forename: Liana Veronica
authors.initials: LV
authors.lastname: Rossato
authors.forename: Júlia Gomes
authors.initials: JG
authors.lastname: Farias
authors.forename: Sibila Trojahn
authors.initials: ST
authors.lastname: Nunes
authors.forename: Luciane Almeri
authors.initials: LA
authors.lastname: Tabaldi
authors.forename: Fabiane Goldschmidt
authors.initials: FG
authors.lastname: Antes
authors.forename: Erico Marlon Moraes
authors.initials: EM
authors.lastname: Flores
authors.forename: Maria Rosa Chitolina
authors.initials: MR
authors.lastname: Schetinger
authors.forename: Fernando Teixeira
authors.initials: FT
authors.lastname: Nicoloso
mesh_terms: D027703:Amaranthaceae / Q000187:drug effects* / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D008628:Mercury / Q000494:pharmacology*; D018384:Oxidative Stress / Q000187:drug effects*; D018517:Plant Roots / Q000187:drug effects / Q000378:metabolism; D018520:Plant Shoots / Q000187:drug effects / Q000378:metabolism; D015032:Zinc / Q000494:pharmacology*
chemical_list: D008628:Mercury; D015032:Zinc