LDL apheresis reduces the susceptibility of LDL to in vitro oxidation in a diabetic patient with hemodialysis treatment

OBJECTIVE - We studied whether LDL apheresis would alter the susceptibility of LDL to in vitro oxidative modification induced by copper ion in a diabetic patient undergoing hemodialysis treatment. RESEARCH DESIGN AND METHODS - Isolated LDL was dialyzed against phosphate-buffered saline and resuspended at a concentration of 0.3 mg cholesterol mass/ml buffer. LDL oxidation was then initiated by addition of 1.66 mu mol/l CuSO4, and the formation of conjugated dienes was continuously monitored spectrophotometrically at 234 nm. RESULTS - The duration of the lag phase of LDL obtained after LDL apheresis was markedly longer than that of LDL obtained before LDL apheresis. The propagation rate and the maximum conjugated diene formation of LDL oxidation were not changed after LDL apheresis. CONCLUSIONS - A LDL subfraction that was susceptible to oxidation was removed by LDL apheresis, resulting in reduction of susceptibility of LDL to in vitro oxidation remaining in plasma. LDL apheresis may be of clinical importance for preventing atherosclerotic disease in diabetic patients undergoing hemodialysis.