Effect of vitamin E on the degradation of hydrogen peroxide in cultured human umbilical vein endothelial cells.
Vitamin E reacts with radicals such as lipid peroxyl radical (LOO*) and singlet oxygen ((1)O2), and plays a role in inhibiting lipid peroxidation in cell membranes and preventing the oxidation of low-density lipoproteins (LDL). However, only a few studies have investigated the effect of vitamin E on the degradation of hydrogen peroxide (H2O2). Therefore, we examined the effect of vitamin E on glutathione redox cycle-dependent H2O2 degradation activity in human umbilical vein endothelial cells (HUVEC). Confluent HUVEC were cultured for seven days in media containing various concentrations of vitamin E (alpha-tocopherol). The level of glutathione redox cycle-dependent H2O2 degradation activity and the intracellular glutathione level were determined. HUVEC that had been cultured in the presence of higher concentrations of vitamin E had a higher level of H2O2 degradation activity and a higher intracellular content of the reduced form of glutathione (GSH). Therefore, it is suggested that the vitamin E-induced increase in H2O2 degradation activity in HUVEC results from an increase in intracellular GSH level.
Shimpuku
H
H
Department of Pharmacology, Osaka Dental University, Hirakata, Japan.
Tachi
Y
Y
Shinohara
M
M
Ohura
K
K
D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D004730:Endothelium, Vascular / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D005978:Glutathione / Q000378:metabolism; D006801:Humans; D006861:Hydrogen Peroxide / Q000378:metabolism*; D013997:Time Factors; D014471:Umbilical Veins; D014810:Vitamin E / Q000494:pharmacology*
D014810:Vitamin E; D006861:Hydrogen Peroxide; D005978:Glutathione