Prooxidant activity of β-carotene under 100% oxygen pressure in rat liver microsomes

doi:10.1016/0891-5849(95)00094-E

Free Radical Biology and Medicine

Volume 19, Issue 6, December 1995, Pages 887-892

https://doi.org/10.1016/0891-5849(95)00094-E Get rights and content

Abstract

The effects of the partial pressure of oxygen (pO₂ on antioxidant efficiency of β-carotene in inhibiting 2,2′-azobis(2-amidinopropane) (AAPH)-induced lipid peroxidation are investigated in rat liver microsomal membranes. The rate of peroxyl radicals generated by thermolysis of AAPH at 37°C is markedly higher at 150 than 760 mm Hg pO₂. At 150 mm Hg pO₂ β-carotene acts as an antioxidant, inhibiting 2,2′-azobis(2-amidinopropane) (AAPH)-induced Malondialdehyde (MDA) formation. At 760 mm Hg pO₂, it loses its antioxidant activity and shows a prooxidant effect, increasing lipid peroxidation products, α-Tocopherol prevents the prooxidant effect of β-carotene in a dose-dependent manner. Our data provide the first evidence of a prooxidant effect of β-carotene under 100% oxygen pressure in a biological membrane model and point out the existence of cooperative interactions between β-carotene and α-tocopherol.

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Brief communicationProoxidant activity of β-carotene under 100% oxygen pressure in rat liver microsomes

Abstract

Eur. J. Cancer

Free Radic. Biol. Med.

Methods Enzymol.

Nutr.

J. Biol. Chem.

FEBS Lett.

Free Radic. Biol. Med.

Arch. Biochem. Biophys.

Free Radic. Biol. Med.

Anal. Biochem.

Methods Enzymol.

Chem. Phys. Lett.

Free Radic. Biol. Med.

Methods Enzymol.

Free Radic. Biol. Med.

Free Radic. Biol. Med.

Brief communication
Prooxidant activity of β-carotene under 100% oxygen pressure in rat liver microsomes