title: Effect of acute administration of L-tyrosine on oxidative stress parameters in brain of young rats.
abstract: Tyrosinemia type II, also known as Richner-Hanhart syndrome, is an autosomal recessive inborn error of metabolism caused by a deficiency of hepatic cytosolic tyrosine aminotransferase, and is associated with neurologic and development difficulties in numerous patients. Considering that the mechanisms underlying the neurological dysfunction in hypertyrosinemic patients are poorly known and that studies demonstrated that high concentrations of tyrosine provoke oxidative stress in vitro and in vivo in the cerebral cortex of rats, in the present study we investigate the oxidative stress parameters (enzymatic antioxidant defenses, thiobarbituric acid-reactive substances and protein carbonyl content) in cerebellum, hippocampus and striatum of 30-old-day rats after acute administration of L-tyrosine. Our results demonstrated that the acute administration of L-tyrosine increased the thiobarbituric acid reactive species levels in hippocampus and the carbonyl levels in cerebellum, hippocampus and striatum. In addition, acute administration of L-tyrosine significantly decreased superoxide dismutase activity in cerebellum, hippocampus and striatum, while catalase was increased in striatum. In conclusion, the oxidative stress may contribute, along with other mechanisms, to the neurological dysfunction characteristic of hypertyrosinemia and the administration of antioxidants may be considered as a potential adjuvant therapy for tyrosinemia, especially type II.
authors.affiliation: Laboratório de Bioenergética, Programa de Pós-graduação em Ciências da Saúde, Universidade do Extremo Sul Catarinense, Av. Universitária 1105, Criciúma, SC, 88806-000, Brazil.
authors.forename: Livia G R P
authors.initials: LG
authors.lastname: Macêdo
authors.forename: Milena
authors.initials: M
authors.lastname: Carvalho-Silva
authors.forename: Gabriela K
authors.initials: GK
authors.lastname: Ferreira
authors.forename: Júlia S
authors.initials: JS
authors.lastname: Vieira
authors.forename: Natália
authors.initials: N
authors.lastname: Olegário
authors.forename: Renata C
authors.initials: RC
authors.lastname: Gonçalves
authors.forename: Francieli S
authors.initials: FS
authors.lastname: Vuolo
authors.forename: Gustavo C
authors.initials: GC
authors.lastname: Ferreira
authors.forename: Patrícia F
authors.initials: PF
authors.lastname: Schuck
authors.forename: Felipe
authors.initials: F
authors.lastname: Dal-Pizzol
authors.forename: Emilio L
authors.initials: EL
authors.lastname: Streck
mesh_terms: D000818:Animals; D001921:Brain / Q000187:drug effects* / Q000201:enzymology / Q000378:metabolism; D002374:Catalase / Q000378:metabolism*; D008297:Male; D018384:Oxidative Stress / Q000187:drug effects*; D051381:Rats; D017208:Rats, Wistar; D013482:Superoxide Dismutase / Q000378:metabolism; D014443:Tyrosine / Q000008:administration & dosage* / Q000494:pharmacology
chemical_list: D014443:Tyrosine; D002374:Catalase; D013482:Superoxide Dismutase