Atheromas peroxidation

Overall, and contrary to others (Lyons, 1991), we feel that the weight of scientific evidence indicates that lipid peroxidation is increased in diabetes irrespective of whether complications are present or not. The presence of microangiopathy or severe atheroma is likely to increase the degree of peroxidation even further. 

Circulating lipid peroxides are markedly raised in patients with extensive atheroma... 

Body iron level and iron depletion play an important role in the gender differences seen in death from cardiac disease. There is a better correlation with heart disease mortality in iron levels compared with levels of cholesterol (5). It was found that risk of coronary heart disease (6) and carotid atherosclerosis (7) is associated with increased iron stores. However, impaired endothelium-derived nitric oxide activity may be without overt atherosclerosis in patients with risk factors and may be associated with the presence of atherosclerosis (4). Thus, endothelial dysfunction related to iron activity not only may be an early marker for cardiovascular risk but also may contribute to the pathogenesis of atherosclerosis (2) by the stimulation of low-density lipoproteins (LDL) and membrane lipid peroxidation (I) and may be a key to the understanding of early mechanism in the development of atheroma (7,8). Nakayama et al. (9) showed the role of heme oxygenase induction in the modulation of macrophage activation in atherosclerosis. However, Howes et al. (10) concludes that at the moment, the available evidence on iron hypothesis remains circumstantial. Moreover, Kiechl et al. (7) showed that the adverse effect of iron is hypercholesterolemia, In patients... 

Cardiovascular diseases are known to be accompanied by activation of lipid peroxidation processes in blood. The evidence that oxidative modification of LDL may play an important causative role in atherosclerosis has been increasing rapidly over the past several years. One of the important challenges that remains in this field of research is to go beyond the risk-factor concept to a comprehensive understanding of the biochemical mechanisms responsible for initiation and progression of lesions, and in particular to identity factors essential for atheroma development that might be susceptible to therapeutic intervention. 

Both LC-MS and MS/MS have permitted greatly improved analyses of various lipid oxidation products in the form of the intact neutral and polar lipid molecules or their partial degradation products, which was not possible by chromatographic methods alone. Thus, the hydroperoxides, epoxides, hydroxides, isoprostanes, and the core aldehydes and acids generated during nonenzymatic peroxidation have been identified in plasma lipoproteins and atheroma samples and have provided a new basis for hypotheses about the origin and progression of vascular disease. 

Saturated FAs cause an increase in LDL and cholesterol. Although cholesterol is important as a precursor to bile formation, it is also involved in atheroma formation. Cholesterol can be lowered by raising the intake of polyunsaturated FAs, however they should be taken with antioxidant nutrients to prevent FA peroxidation. 

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