title: Effect of selenium on expression of selenoproteins in mouse fibrosarcoma cells.
abstract: Selenium (Se), an essential trace element, is incorporated into selenoproteins as selenocysteine using insertion machinery, including UGA codon and selenocysteine insertion sequence (SECIS) element in the 3'-untranslated region (3'-UTR) of mRNA. To assess the biological effects of tumor cells exposed to the elevated, but nontoxic Se level on glutathione peroxidase (GPx1 [cellular] and GPx3 [extracellular]), thioredoxin reductase (TrxR), and selenoprotein P (SeP) mRNA expression, we introduced a semiquantitative reverse transcription-polymerase chain reaction technique for each selenoprotein transcript using beta-actin as a reference housekeeping gene in mouse fibroblasts (WEHI 164). Cell lines were cultured with 1.0, 2.5, and 5.0 ng of Se in 1 mL of medium for 3 and 7 d, apart from the control cell line with standard medium. It was found that Se exerts a statistically significant (p<0.05) effect only on GPx3 mRNA, referred to as the optical density (OD) ratio (GPx3/beta-actin). Moreover, the lowest Se level affected GPx3 mRNA expression more strongly than its highest concentrations. In an in vitro model applied in this study, GPx3 gene expression is most specific for Se supplementation.
authors.affiliation: Department of Toxicology and Carcinogenesis, Nofer Institute of Occupational Medicine, Lodz, Poland.
authors.forename: Edyta
authors.initials: E
authors.lastname: Reszka
authors.forename: Jolanta
authors.initials: J
authors.lastname: Gromadzinska
authors.forename: Malgorzata
authors.initials: M
authors.lastname: Stanczyk
authors.forename: Wojciech
authors.initials: W
authors.lastname: Wasowicz
mesh_terms: D000199:Actins / Q000096:biosynthesis; D000818:Animals; D005354:Fibrosarcoma; D015870:Gene Expression / Q000187:drug effects; D005979:Glutathione Peroxidase / Q000096:biosynthesis*; D051379:Mice; D011506:Proteins / Q000378:metabolism*; D012643:Selenium / Q000494:pharmacology*; D017279:Selenocysteine / Q000378:metabolism; D051149:Selenoprotein P; D051140:Selenoproteins; D054481:Thioredoxin Reductase 1; D013880:Thioredoxin-Disulfide Reductase / Q000096:biosynthesis; D014407:Tumor Cells, Cultured; D000094765:Glutathione Peroxidase GPX1
chemical_list: D000199:Actins; D011506:Proteins; D051149:Selenoprotein P; D051140:Selenoproteins; D017279:Selenocysteine; C116888:Gpx3 protein, mouse; D005979:Glutathione Peroxidase; D054481:Thioredoxin Reductase 1; D013880:Thioredoxin-Disulfide Reductase; C516125:Txnrd1 protein, mouse; D012643:Selenium; D000094765:Glutathione Peroxidase GPX1; C000722068:Gpx1 protein, mouse