title: Erythrocyte glutathione peroxidase activity and plasma selenium concentration are reduced in maple syrup urine disease patients during treatment.
abstract: Maple syrup urine disease (MSUD) is an inherited disorder caused by a deficiency of the branched-chain alpha-keto acid dehydrogenase complex activity. In the present study we evaluated selenium levels in plasma from MSUD patients at diagnosis and under treatment and the activities of glutathione peroxidase, catalase and superoxide dismutase in erythrocytes from treated patients. We verified that MSUD patients present a significant selenium deficiency at diagnosis, which becomes more pronounced during treatment, as well as a decrease of erythrocyte glutathione peroxidase activity during treatment. In contrast, erythrocyte catalase and superoxide dismutase activities were not altered in these patients. Our present results suggest that the reduction of an important antioxidant enzyme activity may be partially involved in the pathomechanisms of this disorder and that plasma selenium levels must be corrected through dietary supplementation in MSUD patients.
authors.affiliation: Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, and Serviço de Genética Médica, Hospital de Clínicas de Porto Alegre, Porto Alegre, RS, Brazil. aletheagatto@terra.com.br
authors.forename: Alethéa G
authors.initials: AG
authors.lastname: Barschak
authors.forename: Angela
authors.initials: A
authors.lastname: Sitta
authors.forename: Marion
authors.initials: M
authors.lastname: Deon
authors.forename: Amanda T
authors.initials: AT
authors.lastname: Barden
authors.forename: Graziela O
authors.initials: GO
authors.lastname: Schmitt
authors.forename: Carlos S
authors.initials: CS
authors.lastname: Dutra-Filho
authors.forename: Moacir
authors.initials: M
authors.lastname: Wajner
authors.forename: Carmen R
authors.initials: CR
authors.lastname: Vargas
mesh_terms: D002374:Catalase / Q000097:blood; D002648:Child; D002675:Child, Preschool; D004912:Erythrocytes / Q000201:enzymology*; D005260:Female; D005979:Glutathione Peroxidase / Q000097:blood*; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007532:Isoleucine / Q000097:blood; D007930:Leucine / Q000097:blood; D008297:Male; D008375:Maple Syrup Urine Disease / Q000097:blood* / Q000201:enzymology; D012643:Selenium / Q000097:blood*; D013482:Superoxide Dismutase / Q000097:blood; D014633:Valine / Q000097:blood
chemical_list: D007532:Isoleucine; D002374:Catalase; D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase; D007930:Leucine; D012643:Selenium; D014633:Valine