Macrophage cholesterol accumulation and foam cell formation, the hallmark of early atherosclerosis, is the result of enhanced cellular uptake of plasma low density lipoprotein (LDL). Native LDL, has to undergo oxidative modifications in order to be taken up at an enhanced rate by macrophages, leading to foam cell formation. Macrophage uptake of oxidized LDL involves its binding to scavanger rec...

Hypothyroidism leads to an increase of plasma low-density lipoprotein (LDL) cholesterol levels. Oxidation of LDL particles changes their intrinsic properties, thereby enhancing the development of atherosclerosis. T4 has three specific binding sites on apolipoprotein B; furthermore it inhibits LDL oxidation in vitro. We therefore hypothesized that T4 deficiency not only results in elevated LDL-c...

Cholesterol metabolism alteration is a hot topic in the field of Alzheimer's disease (AD). However, data on plasma lipoproteins cholesterol distribution and oxidation in AD and their possible genetic determinants are lacking. The paraoxonase-1 (PON1) gene -107C/T promoter polymorphisms have been found associated with AD. One of the fundamental functions of PON1 enzyme is the inhibition of low-d...

Oxidative modification of low density lipoprotein (LDL) has been suggested as a causal step in atherosclerosis, and both redox-active transition metal ions and superoxide (O2.-) have been implicated in this process. In order to determine the mechanisms of metal ion-dependent oxidation of LDL in the presence of O2.-, LDL was exposed to hypoxanthine (HX) and purified xanthine oxidase (XO) without...

In patients with dementia, 29 diagnosed as probably suffering from Alzheimer's disease and 46 subjects with dementia of vascular origin, and in 41 non demented control subjects LDL oxidation in vitro was compared in carriers of various apolipoprotein E alleles. Restriction isotyping was performed by gene amplification and cleavage with Hhal, LDL oxidation was investigated by determination of co...

Oxidized low density lipoprotein (LDL) possesses several atherogenic properties. The mechanisms by which LDL becomes oxidized in vivo remain unknown, but previous studies have suggested that 15-lipoxygenase may be one of the factors involved in the initiation of LDL oxidation in the arterial wall. 3 wk after a retrovirus-mediated 15-lipoxygenase gene transfer into iliac arteries of normocholest...

Glycation of both protein and lipid components is believed to be involved in LDL oxidation. However, the relative importance of lipid and protein glycation in the oxidation process has not been established, and products of lipid glycation have not been isolated. Using glucosylated phosphatidylethanolamine (Glc PtdEtn) prepared synthetically, we have identified glycated diacyl and alkenylacyl sp...

High-density lipoprotein (HDL) cholesterol level is low in dialysis patients. The HDL that is present is dysfunctional, failing to protect low-density lipoprotein (LDL) from oxidation and reduce levels of oxidized LDL. Addition of the orally absorbable amphipathic peptide 4-F to LDL obtained from dialysis patients protects LDL from oxidation in vitro and reduces the capacity of oxidized LDL to ...

Hemodynamic forces on vasculature profoundly influence atherogenesis. We examined the effect of stretch force on the oxidation of low-density lipoprotein (LDL) by rat aortic smooth muscle cells (RASM) and superoxide production. Stretch force was imposed on RASM cultured on deformable dishes by stretching the dishes. Incubation of native LDL with static RASM for 24 h resulted in LDL oxidation as...

BACKGROUND The endothelial isoform of nitric oxide synthase (eNOS) has been considered to exert an antiatherosclerotic role through synthesis of NO. However, eNOS has been shown to generate superoxide, which could oxidize LDL and promote atherosclerosis. We sought to determine the role of eNOS in diet-induced fatty streak formation through the use of eNOS-deficient mice. METHODS AND RESULTS M...