Accumulation of Zinc in Human Atherosclerotic Lesions Correlates With Calcium Levels But Does Not Protect Against Protein Oxidation

The Heart Research Institute, 114 Pyrmont Bridge Road, Camperdown, Sydney, NSW 2050, Australia.
Arteriosclerosis Thrombosis and Vascular Biology (Impact Factor: 6). 05/2008; 28(5):1024-30. DOI: 10.1161/ATVBAHA.108.162735
Source: PubMed

ABSTRACT Oxidized lipids and proteins, as well as decreased antioxidant levels, have been detected in human atherosclerotic lesions, with oxidation catalyzed by iron and copper postulated to contribute to lesion development. Zinc has been postulated to displace iron from critical sites and thereby protect against damage. In this study, metal ion and protein oxidation levels were quantified in human carotid and abdominal artery specimens containing early-to-advanced lesions, to determine whether zinc concentrations correlate inversely with iron levels and protein oxidation.
Metal ions were quantified by EPR and inductively coupled plasma mass spectroscopy. Native and oxidized protein side-chains were quantified by high-performance liquid chromatography. Elevated levels of zinc ( approximately 6-fold) were detected in advanced lesions compared to healthy tissue or early lesions. Zinc did not correlate negatively with iron or copper levels suggesting that zinc does not displace these metal ions. Highly significant positive correlations (P<0.005) were detected between zinc and calcium levels.
Zinc did not correlate with low iron levels and reduced protein oxidation. These data indicate that zinc does not prevent protein oxidation in advanced lesions. The reported protective effect of zinc accumulation is proposed to be associated with lesion calcification.

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Available from: Johannes Waltenberger, Sep 29, 2015
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    • "It is not possible to ascertain whether calcium and zinc accumulation occurs independently of iron and copper or whether all of these metal ions accumulate concurrently. Little is known about the requirements and functions of zinc in maintaining the integrity of the vasculature and the vascular endothelium [29]. In the case of arterial wall samples, the authors obtained significant differences between the concentration of Ca in the control group and its concentration in AO, and also between the concentration of Ca in the control group and Mg in the AO group. "
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    ABSTRACT: The study was aimed to evaluate the influence of the vascular disease, atherosclerotic obliterans (AO), on the location and concentration of elements in the arterial wall and serum. Use of a modern method for studying element’s concentration and distribution in samples of clinical material, i.e. laser ablation inductively coupled plasma mass spectrometry, is presented. Elements are not equally distributed between the inner (intima) and the outer (media + adventitia) layer of the arterial wall. Among the studied elements, calcium was found to have an unquestionable role in the calcification of the wall. Increased concentration of calcium found in the inner part of the atherosclerotic arterial wall and in the plaque, as compared to the control arterial wall samples, demonstrates the unquestionable role of this element in the calcification of the wall observed in AO. Applied chemometric methods were useful for demonstrating the differences in the element’s concentration in blood serum and the arterial wall samples between AO and the control group. Figure Image of the ruptured atherosclerotic plaque done while surgery
    Analytical and Bioanalytical Chemistry 02/2011; 399(9):3221-31. DOI:10.1007/s00216-011-4729-5 · 3.44 Impact Factor
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    • "Human atherosclerotic plaque contains oxidized lipids, proteins [48], hydroperoxides [49], cholesterol, oxidized cholesterol products [11], oxidized and aggregated LDL, and decreased antioxidant levels [50]. One of the most significant constituents related to early plaque development is the accumulation of lipid peroxides with plaque progression. "
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    ABSTRACT: The role of transition metal ions in atherogenesis is controversial; they may be involved in hydroxyl radical generation and can also catalyze the reactive oxygen species neutralization reaction as cofactors of antioxidant enzymes. Using EPR spectroscopy, we revealed that 70% of aorta specimens with atherosclerotic lesions possessed superoxide dismutase activity, 100% of the specimens initiated Fenton reaction and demonstrated the presence of manganese paramagnetic centers. The sodA gene encoding manganese-dependent bacterial superoxide dismutase was not found in the samples of atherosclerotic plaques by PCR using degenerate primers. The data obtained indicate prospects of manganese analysis as a marker element in the express diagnostics of atherosclerosis. Keywordsatherosclerosis–superoxide dismutase–manganese– sodA gene
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