Antioxidant activity of aminoethylcysteine ketimine decarboxylated dimer on copper‐induced LDL oxidation

Abstract

Abstract Aminoethylcysteine ketimine decarboxylated dimer (AECK‐DD), a member of a family of natural cyclic sulfur‐containing aminoacids, recently detected in biological samples, protects low density lipoprotein (LDL) against copper‐mediated oxidation, as assessed by monitoring the kinetics of conjugated diene formation, thiobarbiturie acid‐reactive substances production and LDL‐tryptophan fluorescence quenching. Moreover, AECK‐DD exerts a protective effect also against metal‐independent, peroxyl radical‐induced lipoprotein oxidation. It is of note that the concentrations exerting a protective effect against LDL oxidation are similar to those found in biological samples.