Ferric(III) ions inhibits copper(II)/hydrogen peroxide-catalyzing lipid peroxidation in human erythrocyte membranes.
1. Effect of ferric ions (Fe3+) on the lipid peroxidation catalyzed by copper ions (Cu2+) and hydrogen peroxide (H2O2) was studied in human erythrocyte membranes. 2. The formation of thiobarbituric acid-reactive products elicited by CuCl2/H2O2 was inhibited by FeCl3 in a concentration-dependent manner; 0.25 mM FeCl3 were enough to cause 50% inhibition of the formation of peroxides. 3. The inhibitory effect of FeCl3 is not due to competition against Cu2+. 4. FeCl3 inhibited the initiation, but did not inhibit the propagation of Cu2+/H2O2-catalyzing lipid peroxidation. 5. In the heat- or trypsin-treated erythrocyte membranes, FeCl3 had no inhibitory effect on Cu2+/H2O2-catalyzing lipid peroxidation. 6. Sodium azide, an inhibitor of catalase, had no effect on the inhibitory effect of FeCl3. 7. These results suggest that a protein factor(s), which is not catalase, is involved in the inhibition of Cu2+/H2O2-catalyzing lipid peroxidation by Fe3+.
Nagashima
K
K
Department of Endodontics, Nihon University School of Dentistry, Chiba, Japan.
Yamazaki
M
M
Sugiya
H
H
Sawada
M
M
Furuyama
S
S
D003300:Copper / Q000097:blood*; D004910:Erythrocyte Membrane / Q000378:metabolism*; D005290:Ferric Compounds / Q000494:pharmacology*; D006801:Humans; D006861:Hydrogen Peroxide / Q000097:blood*; D066298:In Vitro Techniques; D007700:Kinetics; D015227:Lipid Peroxidation / Q000187:drug effects*
D005290:Ferric Compounds; D003300:Copper; D006861:Hydrogen Peroxide