Flavonoids can replace alpha-tocopherol as an antioxidant.
Endogenous antioxidants such as the lipid-soluble vitamin E protect the cell membranes from oxidative damage. Glutathione seems to be able to regenerate alpha-tocopherol via a so-called free radical reductase. The transient protection by reduced glutathione (GSH) against lipid peroxidation in control liver microsomes is not observed in microsomes deficient in alpha-tocopherol. Introduction of antioxidant flavonoids, such as 7-monohydroxyethylrutoside, fisetin or naringenin, into the deficient microsomes restored the GSH-dependent protection, suggesting that flavonoids can take over the role of alpha-tocopherol as a chain-breaking antioxidant in liver microsomal membranes.
van Acker
F A
FA
Department of Medical Oncology, BR-232, University Hospital Vrije Universiteit, De Boelelaan 1117, 1081 HV, Amsterdam, The Netherlands. f.vanacker@azvu.nl
Schouten
O
O
Haenen
G R
GR
van der Vijgh
W J
WJ
Bast
A
A
D000818:Animals; D000975:Antioxidants / Q000494:pharmacology*; D044950:Flavanones; D005419:Flavonoids / Q000494:pharmacology*; D044948:Flavonols; D005978:Glutathione / Q000494:pharmacology; D006896:Hydroxyethylrutoside / Q000494:pharmacology; D015227:Lipid Peroxidation / Q000187:drug effects; D008297:Male; D008862:Microsomes, Liver / Q000187:drug effects / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D014810:Vitamin E / Q000378:metabolism / Q000494:pharmacology*
D000975:Antioxidants; D044950:Flavanones; D005419:Flavonoids; D044948:Flavonols; D006896:Hydroxyethylrutoside; D014810:Vitamin E; D005978:Glutathione; C005273:naringenin; C017875:fisetin