Prooxidant activity of beta-carotene under 100% oxygen pressure in rat liver microsomes.
Free Radic Biol Med
; 19(6): 887-92, 1995 Dec.
Article
en En
| MEDLINE
| ID: mdl-8582664
ABSTRACT
The effects of the partial pressure of oxygen (pO2) on antioxidant efficiency of beta-carotene in inhibiting 2,2'-azobis(2-amindinopropane) (AAPH)-induced lipid peroxidation are investigated in rat liver microsomal membranes. The rate of peroxyl radicals generated by thermolysis of AAPH at 37 degrees C is markedly higher at 150 than 760 mm Hg pO2. At 150 mm Hg Po2 beta-carotene acts as an antioxidant, inhibiting 2,2'-azobis(2-amidinopropane) 9AAPH0-induced Malonidaldehyde (MDA) formation. At 760 mm Hg Po2, it loses its antioxidant activity and shows a prooxidant effect, increasing lipid peroxidation products. alpha-Tocopherol prevents the prooxidant effect of beta-carotene in a dose-dependent manner. Our data provide the first evidence of a prooxidant effect of beta-carotene under 100% oxygen pressure in a biological membrane model and point out the existence of cooperative interactions between beta-carotene and alpha-tocopherol.
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Colección:
01-internacional
Banco de datos:
MEDLINE
Asunto principal:
Oxígeno
/
Microsomas Hepáticos
/
Peroxidación de Lípido
/
Carotenoides
/
Antioxidantes
Límite:
Animals
Idioma:
En
Revista:
Free Radic Biol Med
Asunto de la revista:
BIOQUIMICA
/
MEDICINA
Año:
1995
Tipo del documento:
Article
País de afiliación:
Italia