[A comparative study of the antioxidant properties of polyhydroxamic acids, desferal and other iron chelating agents]

The effects of different iron chelators on both OH.-generation in Fenton reaction and lipid peroxidation products accumulation in brain homogenate were studied. Intensity of luminol-dependent chemiluminescence was the measure of OH.-radical generation. The rate of lipid peroxidation was estimated as malondialdehyde accumulation. It was shown, that inhibition of chemiluminescence by the tested substances increased in next series: ADP, polyhydroxamic acid (PHA), EDTA, desferal, o-phenanthroline, ascorbate. Inhibition of lipid peroxidation by these substances increased in other order: ADP, Ascorbate, EDTA, PHA, desferal, o-phenanthroline. The results obtained allow to conclude, that antioxidant activity of ascorbate is due to the trapping of OH. radicals; in contrast, inhibition of the free radical processes by other tested substances is due to binding of iron ions. Antioxidant effect of PHA is almost as strong as effects of desferal, o-phenanthroline and EDTA. The lowest antioxidant activity was found in the presence of ADP.