Tehran University of Medical Sciences Acta Medica Iranica 0044-6025 48 5 2010 10 15 289 294 EN Mohammad Ali Ghaffari Cellular and Molecular Research Center and Department of Biochemistry, School of Medical, Ahwaz Jundishapour University of Medical Sciences, Ahwaz, Iran. Taibeh Ghiasvand Cellular and Molecular Research Center and Department of Biochemistry, School of Medical, Ahwaz Jundishapour University of Medical Sciences, Ahwaz, Iran. 2015 09 28 We studied the effect of different concentrations of alpha-tocopherol on in vitro cupric ions induced oxidation of low density lipoproteins (LDL). Human native LDL (50 µg protein/ml) oxidation was induced by 10 µmol/L of CuSO4. Conjugated dienes were measured spectrophotometrically for up to 440 minutes. The length of the lag phase (Tlag), maximum velocity of the reaction (Vmax) and the maximum amount of generated dienes were obtained from kinetic data. Alpha-tocopherol increased Tlag and decreased Vmax with a dependence upon concentration (0-100 µmol/L). There was no difference between the Dmax obtained with cupric ions alone or in the presence of the various concentrations of alpha-tocopherol. The results suggest that alpha-tocopherol may decrease free radicals presence in LDL and thus decrease velocity of LDL oxidation by cupric ions. This mechanism may be a reason for alpha-tocopherol effect in ameliorating atherosclerosis. https://acta.tums.ac.ir/index.php/acta/article/view/4050 https://acta.tums.ac.ir/index.php/acta/article/download/4050/4025