The influence of different plasma triglyceride concentrations on the heterogeneity of low density lipoprotein (LDL) and on the susceptibility of LDL to copper oxidation was investigated. By density gradient ultracentrifugation, LDL subfractions were isolated from the plasma of 10 normolipidemic control subjects and 12 hypertriglyceridemic patients both before and after clofibrate treatment. In ...

Although sphingomyelin (SPH) is a major constituent of all lipoproteins, its physiological function in plasma is not known. In this study, we tested the hypothesis that SPH inhibits lipid peroxidation in low density lipoproteins (LDL) because of its effects on surface fluidity and packing density and that the relative resistance of the buoyant LDL to oxidation, compared with the dense LDL, is p...

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...

BACKGROUND Postmenopausal estrogen replacement therapy (ERT) has an antioxidant effect that opposes the oxidation of LDL particles. Oral ERT-induced increases in plasma triglyceride, however, decrease LDL particle size, which may counteract this antioxidant effect. Because transdermal ERT decreases plasma triglyceride, it may not decrease LDL particle size and may preserve estrogen's antioxidan...

The regulation of macrophage lipoprotein lipase (LPL) secretion and mRNA expression by atherogenic lipoproteins is of critical relevance to foam cell formation. LPL is present in arterial lesions and constitutes a bridging ligand between lipoproteins, proteoglycans, and cell receptors, thus favoring macrophage lipoprotein uptake and lipid accumulation. We investigated the effects of native and ...

OBJECTIVES The purpose of this study was to investigate the susceptibility of estrogen-induced small low density lipoprotein (LDL) particles to oxidation. BACKGROUND Estrogen replacement therapy in postmenopausal women has an antioxidant effect that opposes oxidation of LDL particles. Estrogen-induced increases in plasma triglyceride concentrations, however, decrease LDL particle size, which ...

A randomized, double-masked, placebo-controlled cross-over trial was carried out to evaluate whether ubiquinone supplementation (180 mg daily) corrects impaired defence against initiation of oxidation of low density lipoprotein (LDL) related to effective (60 mg daily) lovastatin treatment. Nineteen men with coronary heart disease and hypercholesterolemia received lovastatin with or without ubiq...

The exposure of proteins to high concentrations of glucose in vitro is widely considered a relevant model of the functional degeneration of tissue occurring in diabetes mellitus. In particular, the enhanced atherosclerosis in diabetes is often discussed in terms of glycation of low-density lipoprotein (LDL), the non-enzymic attachment of glucose to apolipoprotein amino groups. However, glucose ...