Essential requirement of reduced glutathione (GSH) for the anti-oxidant effect of the flavonoid quercetin.
We have analyzed the anti- or pro-oxidant effects of the flavonoid quercetin (QU) by evaluating, in U937 cell line, hydrogen peroxide (H(2)O(2)), superoxide anion reduced glutathione (GSH) content, mitochondrial membrane potential, DNA content, phosphatidylserine exposure on the outer face of the plasma membrane and cell viability. Polychromatic flow cytometry was used to evaluate in the same cells several functional parameters. For short periods of treatment QU exerted an anti-oxidant effect (decrease in H(2)O(2) levels), whereas for long periods it showed a pro-oxidant activity (increase in ). In these conditions, GSH content was reduced, and this correlated with a lack of anti-oxidant activity of QU, which in turn could be correlated with proapoptotic activity of this molecule. Thus, QU can exert different effects (anti-/prooxidant) depending on exposure times and oxidative balance, and in particular on stores of GSH.
Ferraresi
Roberta
R
University of Modena and Reggio Emilia School of Medicine, Department of Biomedical Sciences, Italy.
Troiano
Leonarda
L
Roat
Erika
E
Lugli
Enrico
E
Nemes
Elisa
E
Nasi
Milena
M
Pinti
Marcello
M
Fernandez
Maria I Garcia
MI
Cooper
Edwin L
EL
Cossarizza
Andrea
A
D000975:Antioxidants / Q000378:metabolism* / Q000494:pharmacology*; D002470:Cell Survival; D005419:Flavonoids / Q000737:chemistry; D005434:Flow Cytometry; D016166:Free Radical Scavengers; D005978:Glutathione / Q000378:metabolism*; D006801:Humans; D006861:Hydrogen Peroxide / Q000494:pharmacology; D015227:Lipid Peroxidation; D008564:Membrane Potentials; D008928:Mitochondria / Q000473:pathology; D016877:Oxidants / Q000737:chemistry; D018384:Oxidative Stress; D010718:Phosphatidylserines / Q000737:chemistry; D011794:Quercetin / Q000737:chemistry / Q000494:pharmacology*; D013481:Superoxides; D013997:Time Factors; D020298:U937 Cells
D000975:Antioxidants; D005419:Flavonoids; D016166:Free Radical Scavengers; D016877:Oxidants; D010718:Phosphatidylserines; D013481:Superoxides; D011794:Quercetin; D006861:Hydrogen Peroxide; D005978:Glutathione