A simple method for assessing copper-mediated oxidation of very-low-density lipoprotein isolated by rapid ultracentrifugation.

Department of Clinical Biochemistry, Queen's University, Belfast, UK.
Annals of Clinical Biochemistry (Impact Factor: 2.08). 08/1998; 35 ( Pt 4):504-14. DOI: 10.1177/000456329803500404
Source: PubMed

ABSTRACT The association of very-low-density lipoprotein (VLDL) with atherosclerosis remains controversial. However, studies have shown that oxidative modification of VLDL can promote foam cell formation, leading to the development of atherosclerosis. A rapid method is described which will allow the significance of VLDL oxidation to be assessed in clinical studies. VLDL was isolated from heparinized plasma by a 1-h, single spin ultracentrifugation. Total protein was standardized to 25 mg/L. Oxidation was promoted by the addition of copper ions (17.5 mumol/L, final concentration) incubated at 37 degrees C. Conjugated diene production 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 (-70 degrees C) was stable for 15 weeks. This simple, rapid method for the isolation of VLDL may be applied to assess the significance of VLDL oxidation in disease.

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