engleski

The role of iron in reactions of free-radical induced modifications of unsaturated fatty acids

In this presentation the role of iron in the deleterious oxidation of unsaturated fatty acids will be discussed. The kinetics of iron(II) ion oxidation by an alkyl hydroperoxide, with a special attention given to the rate of oxidation of iron(II) as affected by the medium composition in solutions, were reexamined and somewhat revised. Since many medical aspects of cellular damage are related with the peroxidation of unsaturated lipids, iron-mediated peroxidation processes were studied in lipid model micelar systems. Together with lipid peroxidation processes radical-based lipid modifications could also be considered. Thiols are considered to be effective scavengers of reactive oxygen species and peroxyl radicals as the propagators of lipid peroxidation. On the other hand, the reactivity of thiols towards radical species generates thiyl radicals that are strongly connected with the isomerization of lipid double bonds with formation of the geometrical trans lipid isomers. The model micellar systems have been also evaluated for lipid isomerization caused by thiyl radicals generated from -mercaptoethanol by-radiolysis of these systems, under different oxidative conditions. Using the existing methods for the detection and quantitation of lipid peroxidation products the influence of iron ions on peroxidation of unsaturated fatty acid accompanied by the geometrical isomerization in lipid model systems was also studied.

iron; free radicals; lipid peroxidation; geometrical isomerization

nije evidentirano