Importance of iron in lipid peroxidation in the tyrosinase/4-hydroxyanisole system: possible mechanism of killing of malignant melanoma cells by 4-hydroxyanisole.
Phospholipid peroxidation of unsaturated phospholipid liposomes in the tyrosinase(mushroom)-4-hydroxyanisole system was studied in both the presence and absence of Fe3+, as a model of melanocyte damage by this agent. Ferric ion is required for the lipid peroxidation, and maximal lipid peroxidation was achieved with a molar ratio of [Fe3+]/[4-hydroxyanisole] of about 1. The lipid peroxidation was significantly inhibited by ceruloplasmin (a ferroxidase), indicating that Fe3+, which would be coordinated with metabolites, catechols, should be reduced to express its oxidant property. Judging from the results obtained with inhibitors or scavengers of active oxygen species, O2-, H2O2, and .OH would not mainly involve in the lipid peroxidation.
Koga
S
S
Photon Medical Research Center, Hamamatsu University School of Medicine, Shizuoka, Japan.
Nakano
M
M
Ito
T
T
Tomita
Y
Y
D000818:Animals; D000840:Anisoles / Q000494:pharmacology*; D000970:Antineoplastic Agents / Q000494:pharmacology*; D002417:Cattle; D006801:Humans; D007501:Iron / Q000378:metabolism*; D007700:Kinetics; D015227:Lipid Peroxidation; D008081:Liposomes; D008545:Melanoma; D014442:Monophenol Monooxygenase / Q000378:metabolism*
D000840:Anisoles; D000970:Antineoplastic Agents; D008081:Liposomes; C009760:mequinol; D007501:Iron; D014442:Monophenol Monooxygenase