Oxidized low density lipoprotein (LDL), formed in vivo from presently unknown reactions, may play a role in atherogenesis. In vitro, transition metals such as iron and copper will facilitate LDL oxidation, but these metals are unlikely to exist in free form in normal body fluids. We have explored the possibility that LDL oxidation may be promoted by heme, a physiologically ubiquitous, hydrophob...

Deposition of oxidized-LDL in vascular walls is essential in the initiation of atherosclerosis. Oxidation of LDL has been attributed to myeloperoxidase as its generation of potent oxidants. However, the exact mechanism of LDL oxidation and foam cell formation in atherosclerosis remains to be elucidated. Vascular peroxidase-1 (VPO1), a newly-identified heme-containing peroxidase, is primarily ex...

Coenzyme Q(10), a lipid soluble benzoquinone, has excellent antioxidant and membrane stabilizing properties in the cardiac tissue. The present study quantitatively investigated the effects of coenzyme Q(10) on in vitro LDL oxidation. The formation of conjugated dienes, malondialdehyde (MDA) and electrophoretic mobility were monitored as markers of the oxidation of LDL, respectively. Coenzyme Q(...

Oxidative modification of low density lipoprotein (LDL) has been suggested to play a casual role in human atherosclerosis, and prevention of LDL oxidation may be an effective strategy to prevent or slow the progression of this disease. It is important, therefore, to identify the factors that determine LDL's susceptibility to oxidation. We have analyzed 62 human LDL samples for content of antiox...

Low-density lipoprotein (LDL) has recently been shown to be oxidized by iron within the lysosomes of macrophages, and this is a novel potential mechanism for LDL oxidation in atherosclerosis. Our aim was to characterize the chemical and physical changes induced in LDL by iron at lysosomal pH and to investigate the effects of iron chelators and α-tocopherol on this process. LDL was oxidized by i...

The effect of fish oil and corn oil supplementation on plasma lipids and lipoproteins and on low density lipoprotein (LDL) oxidation was examined in 20 treated hypertensive subjects. The randomized double-blind crossover study consisted of two 6-week interventions with 4 g/day of a highly purified fish oil or corn oil. Fish oil significantly (-24%, P < 0.01) reduced plasma triglyceride, and inc...

BACKGROUND We studied the antioxidant effects of fresh juice and peel extract of Citrus aurantifolia (Christm). METHODS Low density lipoprotein (LDL) was separated from one hypercholesterolemic human serum by modified Bronzert and Brewer procedure. Oxidation of LDL was measured at 234 nm against 0, 5, 10, 20, 25, 30 and 40 μl of fresh lime juice and 0, 5, 10, 15 and 20 μl of peel polyphenolic...

Recent data suggest that treatment with n-3 fatty acids could enhance the susceptibility of plasma low-density-lipoprotein (LDL) to oxidation. Twelve hypertriacylglycerolemic, hemodialyzed patients were treated with 2.5 g n-3 fatty acids/d for 2 mo. Treatment was then withdrawn for 2 mo (washout phase). Plasma total cholesterol and LDL cholesterol increased significantly (9% and 28%) and plasma...

Damage to apoB100 on low density lipoprotein (LDL) has usually been described in terms of lipid aldehyde derivatisation or fragmentation. Using a modified FOX assay, protein hydroperoxides were found to form at relatively high concentrations on apoB100 during copper, 2,2'-azobis(amidinopropane) dihydrochloride (AAPH) generated peroxyl radical and cell-mediated LDL oxidation. Protein hydroperoxi...

There have been suggestions that oxidation of low density lipoproteins (LDL) might increase their atherogenic potential. Because changes in intracellular free calcium concentration [Ca2+]i have been linked to atherogenesis, we compared the influence of oxidized LDL (Ox-LDL) and native LDL (N-LDL) on [Ca2+]i in vascular smooth muscle cells cultured from rat aortas. For determination of [Ca2+]i, ...