Changes in surface charge of low-density lipoproteins during oxidative modification.

ABSTRACT

The negative surface charge of low-density lipoproteins increased during their oxidative modification induced by autooxidation at 37 degrees C. The degree of changes depended on the time of autooxidation the surface charge remained practically unchanged after short-term oxidation (6-h incubation), but then progressively increased and after 24-h oxidation it 2-fold surpassed the initial level. Long-term incubation of low-density lipoproteins in the presence of EDTA inhibiting lipid peroxidation did not change their surface charge. These changes probably contribute to atherogenic activity of oxidized low-density lipoproteins. The degree of oxidative modification of low-density lipoproteins was precisely estimated using fluorescence probes.