A SIMPLE METHOD FOR ASSESSING COPPER-MEDIATED OXIDATION OF VERY-LOW-DENSITY LIPOPROTEIN ISOLATED BY RAPID ULTRACENTRIFUGATION

The association of very-low-density lipoprotein (VLDL) with atheroscle rosis remains controversial. However, studies have shown that oxidativ e modification of VLDL can promote foam cell formation, leading to the development of atherosclerosis. A rapid method is described which wil l allow the significance of VLDL oxidation to be assessed in clinical studies. VLDL was isolated from heparinized plasma by a 1-h, single sp in ultracentrifugation. Total protein was standardized to 25 mg/L. Oxi dation was promoted by the addition of copper ions (17.5 mu mol/L, fin al concentration) incubated at 37 degrees C. Conjugated diene producti on was followed at 234 nm. Total assay preparation time was 2 h. Urate greatly inhibited the oxidation of VLDL and was successfully removed by size exclusion chromatography. VLDL isolated from frozen plasma (-7 0 degrees C) was stable for 15 weeks. This simple, rapid method for th e isolation of VLDL may be applied to assess the significance of VLDL oxidation in disease.