Prooxidant activity of melatonin promotes fas-induced cell death in human leukemic Jurkat cells.
The antioxidant activity of melatonin (MEL) has been considered to constitute part of its physiological as well as pharmacological effects. However, as described herein we found a profound prooxidant activity of micro- to millimolar concentrations of MEL in the human leukemic Jurkat cell line. This prooxidant effect was increased in glutathione-depleted cells and counteracted by antioxidants. As a consequence MEL promoted fas-induced cell death. These data therefore indicate that MEL may be a modulator of the cellular redox status, but does not necessarily act as an intracellular antioxidant.
Wölfler
A
A
Department of Medicine, University of Graz, Austria.
Caluba
H C
HC
Abuja
P M
PM
Dohr
G
G
Schauenstein
K
K
Liebmann
P M
PM
D000975:Antioxidants / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects*; D002470:Cell Survival / Q000187:drug effects; D005978:Glutathione / Q000378:metabolism; D006801:Humans; D006861:Hydrogen Peroxide / Q000494:pharmacology; D007202:Indicators and Reagents; D019169:Jurkat Cells / Q000378:metabolism / Q000473:pathology*; D008550:Melatonin / Q000494:pharmacology*; D016877:Oxidants / Q000494:pharmacology; D010084:Oxidation-Reduction; D017382:Reactive Oxygen Species / Q000378:metabolism; D012235:Rhodamines; D019014:fas Receptor / Q000378:metabolism*
D000975:Antioxidants; D007202:Indicators and Reagents; D016877:Oxidants; D017382:Reactive Oxygen Species; D012235:Rhodamines; D019014:fas Receptor; D006861:Hydrogen Peroxide; D005978:Glutathione; D008550:Melatonin