Enolizable carbonyl and imino metabolites may act as endogenous sources of reactive oxygen species
Ciênc. cult. (Säo Paulo)
; 47(5/6): 346-57, Sept.-Oct. 1995. ilus
Article
em En
| LILACS
| ID: lil-186431
Biblioteca responsável:
BR1.1
RESUMO
Highly reactive oxyradicals and electronically excited triplet carbonyls can be generated in vitro by iron complexes and heme enzyme-catalyzed aerobic oxidation of synthetic or naturally occurring substances capable of enolization in aqueous medium. Monoenols and enamines, obtained by (alpha-methyne-carbonyl and -imine enolization, undergo dioxygen insertion and ultimately originate triplet species; e.g., isobutanal, 3-methylacetoacetone, Schiff bases. In turn, (alpha-hydroxy- and (alpha-aminocarbonyls (e.g., carbohydrates, 5-aminolevulinic acid) tautomerize to enediols and enolamines and yield oxyradicals, initiated by electron transfer to dioxygen, as polyphenols (e.g., 6-hydroxydopamine) and polyphenolamines do. Free radicals and excited species have been implicated in several normal and pathological processes. We here briefly review our contributions to this research area, emphasizing a possible in vivo prooxidant role for 5-aminolevulinic acid, the heme precursor accumulated in several porphyric disorders (e.g., lead poisoning, acut intermittent porphyria, tyrosinosis).
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Coleções:
01-internacional
Temas:
Geral
Base de dados:
LILACS
Assunto principal:
Técnicas In Vitro
/
Espécies Reativas de Oxigênio
/
Ácido Aminolevulínico
Limite:
Animals
/
Humans
Idioma:
En
Revista:
Ciênc. cult. (Säo Paulo)
Assunto da revista:
CIENCIA
Ano de publicação:
1995
Tipo de documento:
Article