Mature human atherosclerotic plaque contains peroxidized phosphatidylcholine as a major lipid peroxide

Qualitative distribution of endogenous phosphatidylcholine and sphingomyelin in serum using LC-MS/MS based profiling

PCs and SMs are the major types of glycerophospholipids and sphingophospholipids, the two main categories of phospholipids (PLs). To study the qualitative distribution of serum phosphatidylcholine (PC) and sphingomyelin (SM) in human and three rodent species, liquid chromatography-Orbitrap mass spectrometry (LC-Orbitrap-MS/MS) was used to identify them comprehensively through the accurate mass measurement of both precursor ions and their corresponding product ions. Based on the fragmentation rules of standards, the product ions at m/z 184.0733 were filtered to maximally screen possible PC and SM molecules. For PC, the fatty acid at sn-1 and sn-2 of the glycerol backbone was identified based on the product ions in negative mode. A total of 91 PCs and 31 SMs molecular species, consisting of 166 PCs and 39 SMs regioisomers, were detected in human serum, which is the most comprehensive identification of PC and SM species in serum. The qualitative distributions of PC in rat and SM in golden hamster, respectively, were more similar with that of human from an overall perspective. Those results provided guidance regarding to the animal model selection for mimicking lipid related-syndromes or diseases in human.

Direct Separation of the Diastereomers of Cholesterol Ester Hydroperoxide Using LC-MS/MS to Evaluate Enzymatic Lipid Oxidation

Cholesterol ester hydroperoxide (CEOOH) is one of the main lipid oxidation products contained in oxidized low-density lipoprotein (LDL). Previous studies suggest that CEOOH in oxidized LDL is closely related to several diseases. Of the oxidation mechanisms of cholesterol ester (CE) in vivo, it has been suggested that enzymatic oxidation induced by lipoxygenase (LOX) plays an important role. Thus, we attempted to develop a method that can evaluate the enzymatic oxidation of CE via the diastereoselective separation of CEOOH bearing 13RS-9Z,11E-hydroperoxy-octadecadienoic acid (13(RS)-HPODE CE). Firstly, we synthesized the standard of 13(RS)-HPODE CE. Using this standard, the screening of analytical conditions (i.e., column, mobile phase, and column temperature) was conducted, and separation of the diastereomers of 13(RS)-HPODE CE was achieved. The diastereoselective separation of 13(RS)-HPODE CE was also confirmed by LC-MS/MS. The developed method (column, CHIRALPAK IB N-3; mobile phase, hexane:ethanol (100:1, v/v); column temperature, 0 °C) can distinguish between enzymatic oxidation and other oxidation mechanisms of CE. Thus, the method can be expected to provide a greater understanding of the biochemical oxidation mechanisms in vivo. Such information will be essential to further elucidate the involvement of CEOOH in various diseases.

Nutrients, Nutraceuticals, and Xenobiotics Affecting Renal Health

Chronic kidney disease (CKD) affects 8–16% of the population worldwide. In developed countries, the most important risk factors for CKD are diabetes, hypertension, and obesity, calling into question the importance of educating and acting on lifestyles and nutrition. A balanced diet and supplementation can indeed support the maintenance of a general health status, including preservation of renal function, and can help to manage and curb the main risk factors for renal damage. While the concept of protein and salt restriction in nephrology is historically acknowledged, the role of some nutrients in renal health and the importance of nutrition as a preventative measure for renal care are less known. In this narrative review, we provide an overview of the demonstrated and potential actions of some selected nutrients, nutraceuticals, and xenobiotics on renal health and function. The direct and indirect effects of fiber, protein, fatty acids, curcumin, steviol glycosides, green tea, coffee, nitrates, nitrites, and alcohol on kidney health are reviewed here. In view of functional and personalized nutrition, understanding the renal and systemic effects of dietary components is essential since many chronic conditions, including CKD, are related to systemic dysfunctions such as chronic low-grade inflammation.

Catechins Blunt the Effects of oxLDL and its Primary Metabolite Phosphatidylcholine Hydroperoxide on Endothelial Dysfunction Through Inhibition of Oxidative Stress and Restoration of eNOS in Rats

BACKGROUND/AIMS

We explored the effects of catechins (decaffeinated green tea extracts containing (-)-epicatechin, (-)-epigallocatechin, (-)-epicatechin gallate and (-)-epigallocatechin gallate) on atherosclerosis risk factors, oxidized low-density lipoprotein (oxLDL) and its primary metabolite, phosphatidylcholine hydroperoxide (PCOOH) induced oxidative injury in cultured endothelial cell line and rats.

METHODS

We used endothelial cell line and male Wistar rats to determine the effect of catechins on oxLDL or PCOOH induced oxidative injury including apoptosis, H2O2 level, vascular responses and urinary 8-isoprostane and nitrite/nitrate concentration. Plasma catechins concentration was determined by a CoulArray HPLC. Responses of aortic and renal vasoconstriction were evaluated by a transonic meter and a full-field laser perfusion imager.

RESULTS

PCOOH administration significantly increased H2O2 amounts and cell apoptosis and decreased endothelial nitric oxide synthase (eNOS) expression in the cultured endothelial cells. Catechins pretreatment significantly reduced PCOOH-elevated H2O2 amounts, endothelial cell apoptosis and partly recovered eNOS expression. Intravenous administration of oxLDL, PCOOH or H2O2, not native LDL, significantly decreased renal and aortic blood flow associated with enhanced ICAM-1 expression and 4-hydroxynoneal (4-HNE) accumulation, and decreased eNOS expression in the male Wistrar rats. One hour after oral intake of green tea extracts, 4 peaks of catechins were found in the rat plasma. The increased plasma catechins significantly inhibited oxLDL-, PCOOH- or H2O2-induced renal and aortic vasoconstriction, decreased urinary 8-isoprostane levels, renal ICAM-1 expression and 4-HNE accumulation, and restored nitrite/nitrate amounts and eNOS activity.

CONCLUSIONS

Our data suggests that catechins pretreatment decrease PCOOH-induced endothelial apoptosis and arterial vasoconstriction through the action of H2O2 inhibition and eNOS restoration.

Nature and nurture in atherosclerosis: The roles of acylcarnitine and cell membrane-fatty acid intermediates

Macrophages recycle components of dead cells, including cell membranes. When quantities of lipids from cell membranes of dead cells exceed processing capacity, phospholipid and cholesterol debris accumulate as atheromas. Plasma lipid profiles, particularly HDL and LDL cholesterol, are important tools to monitor atherosclerosis risk. Membrane lipids are exported, as triglycerides or phospholipids, or as cholesterol or cholesterol esters, via lipoproteins for disposal, for re-use in cell membranes, or for fat storage. Alternative assays evaluate other aspects of lipid pathology. A key process underlying atherosclerosis is backup of macrophage fatty acid catabolism. This can be quantified by accumulation of acylcarnitine intermediates in extracellular fluid, a direct assay of adequacy of β-oxidation to deal with membrane fatty acid recycling. Further, membranes of somatic cells, such as red blood cells (RBC), incorporate fatty acids that reflect dietary intake. Changes in RBC lipid composition occur within days of ingesting modified fats. Since diets with high saturated fat content or artificial trans-fatty acids promote atherosclerosis, RBC lipid content shifts occur with atherosclerosis, and can show cellular adaptation to pathologically stiff membranes by increased long-chain doubly unsaturated fatty acid production. Additional metabolic changes with atherosclerosis of potential utility include inflammatory cytokine production, modified macrophage signaling pathways, and altered lipid-handling enzymes. Even after atherosclerotic lesions appear, approaches to minimize macrophage overload by reducing rate of fat metabolism are promising. These include preventive measures, and drugs including statins and the newer PCSK9 inhibitors. New cell-based biochemical and cytokine assays provide data to prevent or monitor atherosclerosis progression.

Imaging of oxidation-specific epitopes with targeted nanoparticles to detect high-risk atherosclerotic lesions: progress and future directions

Oxidation-specific epitopes (OSE) within developing atherosclerotic lesions are key antigens that drive innate and adaptive immune responses in atherosclerosis, leading to chronic inflammation. Oxidized phospholipids and malondialdehyde-lysine epitopes are well-characterized OSE present in human atherosclerotic lesions, particularly in pathologically defined vulnerable plaques. Using murine and human OSE-specific antibodies as targeting agents, we have developed radionuclide and magnetic resonance based nanoparticles, containing gadolinium, manganese or lipid-coated ultrasmall superparamagnetic iron oxide, to non-invasively image OSE within experimental atherosclerotic lesions. These methods quantitate plaque burden, allow detection of lesion progression and regression, plaque stabilization, and accumulation of OSE within macrophage-rich areas of the artery wall, suggesting they detect the most active lesions. Future studies will focus on using "natural" antibodies, lipopeptides, and mimotopes for imaging applications. These approaches should enhance the clinical translation of this technique to image, monitor, evaluate efficacy of novel therapeutic agents, and guide optimal therapy of high-risk atherosclerotic lesions.

Elaidate, an 18-carbon trans-monoenoic fatty acid, inhibits β-oxidation in human peripheral blood macrophages

Consumption of trans-unsaturated fatty acids promotes atherosclerosis, but whether degradation of fats in macrophages is altered by trans-unsaturated fatty acids is unknown. We compared the metabolism of oleate (C18:1Δ9-10 cis; (Z)-octadec-9-enoate), elaidate (C18:Δ9-10 trans; (E)-octadec-9-enoate), and stearate (C18:0, octadecanoate) in adherent peripheral human macrophages. Metabolism was followed by measurement of acylcarnitines in cell supernatants by MS/MS, determination of cellular fatty acid content by GC/MS, and assessment of β-oxidation rates using radiolabeled fatty acids. Cells incubated for 44 h in 100 µM elaidate accumulated more unsaturated fatty acids, including both longer- and shorter-chain, and had reduced C18:0 relative to those incubated with oleate or stearate. Both C12:1 and C18:1 acylcarnitines accumulated in supernatants of macrophages exposed to trans fats. These results suggested β-oxidation inhibition one reaction proximal to the trans bond. Comparison of [1-(14)C]oleate to [1-(14)C]elaidate catabolism showed that elaidate completed the first round of fatty acid β-oxidation at rates comparable to oleate. Yet, in competitive β-oxidation assays with [9,10-(3)H]oleate, tritium release rate decreased when unlabeled oleate was replaced by the same quantity of elaidate. These data show specific inhibition of monoenoic fat catabolism by elaidate that is not shared by other atherogenic fats.

Release and capture of bioactive oxidized phospholipids and oxidized cholesteryl esters during percutaneous coronary and peripheral arterial interventions in humans

OBJECTIVES

This study sought to assess whether oxidized lipids are released downstream from obstructive plaques after percutaneous coronary and peripheral interventions using distal protection devices.

BACKGROUND

Oxidation of lipoproteins generates multiple bioactive oxidized lipids that affect atherothrombosis and endothelial function. Direct evidence of their role during therapeutic procedures, which may result in no-reflow phenomenon, myocardial infarction, and stroke, is lacking.

METHODS

The presence of specific oxidized lipids was assessed in embolized material captured by distal protection filter devices during uncomplicated saphenous vein graft, carotid, renal, and superficial femoral artery interventions. The presence of oxidized phospholipids (OxPL) and oxidized cholesteryl esters (OxCE) was evaluated in 24 filters using liquid chromatography, tandem mass spectrometry, enzyme-linked immunosorbent assays, and immunostaining.

RESULTS

Phosphatidylcholine-containing OxPL, including (1-palmitoyl-2-[9-oxo-nonanoyl] PC), representing a major phosphatidylcholine-OxPL molecule quantitated within plaque material, [1-palmitoyl-2-(5-oxo-valeroyl)-sn-glycero-3-phosphocholine], and 1-palmitoyl-2-glutaroyl-sn-glycero-3-phosphocholine, were identified in the extracted lipid portion from all vascular beds. Several species of OxCE, such as keto, hydroperoxide, hydroxy, and epoxy cholesteryl ester derivatives from cholesteryl linoleate and cholesteryl arachidonate, were also present. The presence of OxPL was confirmed using enzyme-linked immunoassays and immunohistochemistry of captured material.

CONCLUSIONS

This study documents the direct release and capture of OxPL and OxCE during percutaneous interventions from multiple arterial beds in humans. Entrance of bioactive oxidized lipids into the microcirculation may mediate adverse clinical outcomes during therapeutic procedures.

Phosphatidylcholine hydroperoxide promotes VEGF-induced angiogenesis in endothelial cells and rat aorta ring cultures

BACKGROUND

Phosphatidylcholine hydroperoxide (PCOOH) is a primary oxidation product of PC, and is markedly accumulated in blood plasma and arterial walls in atherosclerotic animals and humans. The role of PCOOH in the induction of angiogenesis is unknown.

METHODS

In this study, we investigated whether PCOOH stimulated angiogenic responses (e.g., vascular endothelial growth factor (VEGF)-induced cell proliferation, migration, and tube formation, and angiogenesis-related gene/protein expression) in human umbilical vein endothelial cells (HUVEC) and in an ex vivo rat aorta model.

RESULTS

VEGF induced proliferation, migration, and tube formation of HUVEC, and these angiogenic responses were all enhanced by PCOOH but not by native (nonoxidized) PC. The angiogenic effects of PCOOH are considered to be mediated via generation of reactive oxygen species and activation of both PI3K/AKT and MAPK pathways. The angiogenic activities of PCOOH were also confirmed by the rat aortic ring assay.

CONCLUSIONS

These results indicate that PCOOH can elicit several angiogenic responses.

GENERAL SIGNIFICANCE

The present study implies an important role of PCOOH in atherosclerosis progression and plaque instability.

Phosphatidylcholine hydroperoxide-induced THP-1 cell adhesion to intracellular adhesion molecule-1

The accumulation of phosphatidylcholine hydroperoxide (PCOOH), a primary oxidation product of phosphatidylcholine (PC), in blood plasma and tissues has been observed in various pathological conditions, including atherosclerosis. However, the biological roles of PCOOH in these conditions remain unknown. To estimate the atherogenicity of PCOOH, we evaluated the effect of PCOOH on THP-1 monocytic cell adherence to immobilized vascular endothelial cell adhesion molecules. THP-1 cell adhesion to intracellular adhesion molecule-1 (ICAM-1) was dose-dependently increased by addition of PCOOH. Phosphatidylcholine hydroxide (a hydroxyl analog of PCOOH) also induced THP-1 cell adhesion to ICAM-1, whereas nonoxidized PC, sn-2 truncated PCs, and other hydroperoxide compounds did not affect the adhesion. In the PCOOH-treated cells, obvious protruding F-actin-rich membrane structures were formed, and lymphocyte function-associated antigen-1 (LFA-1) was localized to the protruding structures. Cytochalasin D, an actin polymerization inhibitor, suppressed the PCOOH-induced cell adhesion to ICAM-1 and the membrane protrusions. These results indicate that PCOOH evokes LFA-1-mediated cell adhesion to ICAM-1 via actin cytoskeletal organization, and the mechanism may participate in monocyte adherence to the arterial wall in the initiation of atherosclerosis.

Chronic green tea extract supplementation reduces hemodialysis-enhanced production of hydrogen peroxide and hypochlorous acid, atherosclerotic factors, and proinflammatory cytokines

BACKGROUND

Oxidative stress increases in patients with end-stage renal disease and exaggerates the related comorbidities.

OBJECTIVE

The aim of the study was to evaluate the effects of supplementation with decaffeinated green tea extract (catechins) on hemodialysis-induced reactive oxygen species, atherosclerotic disease risk factors, and proinflammatory cytokines.

DESIGN

We enrolled 6 healthy subjects and 54 hemodialysis patients for the study. First, the pharmacokinetics of one oral dose of catechins was compared between healthy subjects (n = 6) and hemodialysis patients (n = 10). Second, in the 10 hemodialysis patients, we compared the antioxidant effects of 3 different doses (0, 455, and 910 mg) of oral catechins with that of oral vitamin C (500 mg) during a hemodialysis session. Third, the other 44 hemodialysis patients participated in a 7-mo interventional study, in which 30 patients received placebo throughout and 14 patients received catechins (455 mg/d) from the third to the fifth month.

RESULTS

After one oral dose, the hemodialysis patients (n = 10) had later peaks and slower decay of plasma catechins than did the healthy subjects. In the 10 hemodialysis patients, catechin supplementation reduced hemodialysis-enhanced plasma hypochlorous acid activity more effectively than did placebo or vitamin C. Between treatments with 455 or 910 mg catechins, no significant difference was found in the reduction of plasma hypochlorous acid activity. Catechins also significantly reduced proinflammatory cytokine expression enhanced by hemodialysis. In the 7-mo interventional study, the 14 patients who received daily supplementation of catechins for 3 mo had less predialysis plasma hydrogen peroxide activity, lower hypochlorous acid activity, and lower phosphatidylcholine hydroperoxide, C-reactive protein, and proinflammatory cytokine concentrations than did the 30 hemodialysis patients who received placebo.

CONCLUSION

Catechins reduce hemodialysis-induced production of hydrogen peroxide and hypochlorous acid, atherosclerotic disease risk factors, and proinflammation.

Studies of phospholipid oxidation by electrospray mass spectrometry: from analysis in cells to biological effects

The oxidation of lipids is important in many pathological conditions and lipid peroxidation products such as 4-hydroxynonenal (HNE) and other aldehydes are commonly measured as biomarkers of oxidative stress. However, it is often useful to complement this with analysis of the original oxidized phospholipid. Electrospray mass spectrometry (ESMS) provides an informative method for detecting oxidative alterations to phospholipids, and has been used to investigate oxidative damage to cells, and low-density lipoprotein, as well as for the analysis of oxidized phosphatidylcholines present in atherosclerotic plaque material. There is increasing evidence that intact oxidized phospholipids have biological effects; in particular, oxidation products of 1-palmitoyl-2-arachidonoyl-sn-glycerophosphocholine (PAPC) have been found to cause inflammatory responses, which could be potentially important in the progression of atherosclerosis. The effects of chlorohydrin derivatives of lipids have been much less studied, but it is clear that free fatty acid chlorohydrins and phosphatidylcholine chlorohydrins are toxic to cells at concentrations above 10 micromolar, a range comparable to that of HNE and oxidized PAPC. There is some evidence that chlorohydrins have biological effects that may be relevant to atherosclerosis, but further work is needed to elucidate their pro-inflammatory properties, and to understand the mechanisms and balance of biological effects that could result from oxidation of complex mixtures of lipids in a pathophysiological situation.

Fructose Ingestion Enhances Atherosclerosis and Deposition of Advanced Glycated End-products in Cholesterol-fed Rabbits

This study was performed to investigate whether the plasma concentration of phosphatidylcholine hydroperoxide (PCOOH), which is a marker of oxidized stress in the blood, increased in cholesterol-fed rabbits, and fructose ingestion promoted this process and aggravated atherosclerosis. Male Japanese white rabbits (age: 12 weeks, and body weight: around 2.0 kg, n = 15) were divided into three groups, (1) a NN group as a normal control fed a standard diet (n = 5), (2) a CN group fed 1.0% cholesterol, and (3) a CF group given both 1.0% cholesterol and 10% fructose-containing tap water. During 8 weeks, plasma PCOOH levels increased significantly in the CN and CF groups compared to the NN group and fructose further raised the PCOOH level. The atherosclerosis was significantly promoted and the deposition of advanced glycation end products (AGEs) was marked in the CF group compared to the CN group. Fructose worsened the atheromatous lesions caused by cholesterol feeding. The mechanism is most likely through lipid peroxidation, which was increased by cholesterol feeding-induced hyperlipidemia, and the formation of AGEs.

Phospholipids and oxophospholipids in atherosclerotic plaques at different stages of plaque development

We identified and quantified the hydroperoxides, hydroxides, epoxides, isoprostanes, and core aldehydes of the major phospholipids as the main components of the oxophospholipids (a total of 5-25 pmol/micromol phosphatidylcholine) in a comparative study of human atheroma from selected stages of lesion development. The developmental stages examined included fatty streak, fibrous plaque, necrotic core, and calcified tissue. The lipid analyses were performed by normal-phase HPLC with on-line electrospray MS using conventional total lipid extracts. There was great variability in the proportions of the various oxidation products and a lack of a general trend. Specifically, the early oxidation products (hydroperoxides and epoxides) of the glycerophosphocholines were found at the advanced stages of the plaques in nearly the same relative abundance as the more advanced oxidation products (core aldehydes and acids). The anticipated linear accumulation of the more stable oxidation products with progressive development of the atherosclerotic plaque was not apparent. It is therefore suggested that lipid infiltration and/or local peroxidation is a continuous process characterized by the formation and destruction of both early and advanced products of lipid oxidation at all times. The process of lipid deposition appears to have been subject to both enzymatic and chemical modification of the normal tissue lipids. Clearly, the appearance of new and disproportionate old lipid species excludes randomness in any accumulation of oxidized LDL lipids in atheroma.

Non-invasive imaging of vulnerable plaques by molecular targeting of oxidized LDL with tagged oxidation-specific antibodies

The concept of the "vulnerable" plaque has recently emerged to explain how quiescent atherosclerotic lesions evolve to cause clinical events. Vulnerable plaques are generally non-obstructive, asymptomatic lesions that may abruptly rupture and induce thrombotic occlusion leading to tissue ischemia and its attendant sequelae. They are responsible for over 50% of cases of sudden death and acute myocardial infarction. The lipid component of vulnerable plaques, which is abundant and highly enriched in oxidized low-density lipoprotein (OxLDL), strongly contributes to their propensity to rupture through physical, inflammatory, and thrombogenic properties. We hypothesized that OxLDL would serve as an ideal target to detect vulnerable plaques. In a series of experimental studies, we have shown that oxidation-specific antibodies (Ox-AB) specifically accumulate in vivo within lipid-rich atherosclerotic lesions but not normal arteries, provide a quantitative measure of the content of OxLDL, allow detection of atherosclerosis progression and regression in the context of enhanced or reduced OxLDL content and non-invasively image atherosclerotic lesions. Ox-AB may be tagged with appropriate labels for use in nuclear scintigraphy, magnetic resonance, or ultrasound imaging. Potential research and clinical applications include studying the natural history of atherosclerosis in animal models and humans, evaluating novel drug or genetic therapies on progression and regression of atherosclerosis, evaluating plaque stability, screening and serial follow-up of high-risk individuals, non-invasive imaging of vulnerable plaques, and assessing the clinical efficacy of new treatments of atherosclerosis.

Lipid composition in atheromatous plaque: evaluation of the lipid three-phase percentage

There is a renewed interest in the study of plaque lipid composition because it is recognized that it, rather than the luminal narrowing, influences the plaque stability and determines patient symptoms. At this purpose, we quantitatively evaluated in the carotid plaque of different categories of patients the expression of triglycerides, phospholipids, cholesterol, free cholesterol, esters of cholesterol, and the percentages of the three-phases (cholesterol, esters of cholesterol, phospholipids) by using the "Roozeboom triangle". Significant differences in the content of specific lipid and the percentage of the three-phases were detected among the different types of plaque evaluated in this study. The analysis of the three-phases by "Roozeboom triangle" may open a new approach in the study of atheromatous plaque and give new information on development of the disease.

Circulating autoantibodies to oxidized LDL correlate with arterial accumulation and depletion of oxidized LDL in LDL receptor-deficient mice

Autoantibodies to oxidized low density lipoprotein (OxLDL) are elevated in some human populations with increased risk of atherosclerosis. To determine whether autoantibody levels to epitopes of OxLDL reflect the extent of aortic atherosclerosis and the content of OxLDL, we measured IgG and IgM autoantibody titers to malondialdehyde (MDA)-LDL and copper-oxidized LDL (Cu-OxLDL) in 43 LDL receptor-deficient mice consuming atherogenic and regression diets. Antibody titers were correlated to percent atherosclerotic surface area, aortic weight, and aortic OxLDL content, measured as the in vivo uptake of (125)I-MDA2, a monoclonal antibody to MDA-LDL. All mice were fed an atherogenic diet for 6 months, and 1 group was euthanized. The other 3 groups were fed an atherogenic diet (fat/CHOL group), normal mouse chow (chow group), or mouse chow supplemented with vitamins E and C (chow+VIT group) for an additional 6 months. After dietary intervention, compared with their own baseline, autoantibody titers to MDA-LDL and Cu-OxLDL increased significantly in the fat/CHOL group, whereas they did not change or decreased significantly in the chow and chow+VIT groups. Aortic weight and surface area showed significant progression in the fat/CHOL group, mild progression in the chow group, and no progression in the chow+VIT group (P<0.001), whereas OxLDL content actually decreased in the latter 2 groups (P<0.001). Significant correlations were seen with MDA-LDL autoantibody titers and OxLDL content (IgM, R=0.64 and P=0.0009; IgG, R=0.52 and P=0.009), as well as with percent surface area and aortic weight. These data support the hypothesis that autoantibody titers to OxLDL reflect changes in OxLDL content in atherosclerotic lesions of LDL receptor-deficient mice. Whether autoantibody titers to OxLDL will provide similar valuable insights into the extent of human atherosclerosis, particularly anatomic measurements of plaque burden and OxLDL content, remains to be determined.

Vitamins E plus C and interacting conutrients required for optimal health. A critical and constructive review of epidemiology and supplementation data regarding cardiovascular disease and cancer

Antioxidants are crucial components of fruit/vegetable rich diets preventing cardiovascular disease (CVD) and cancer: plasma vitamins C, E, carotenoids from diet correlate prevalence of CVD and cancer inversely, low levels predict an increased risk of individuals which is potentiated by combined inadequacy (e.g., vitamins C + E, C + carotene, A + carotene); self-prescribed rectification of vitamins C and E at adequacy of other micronutrients reduce forthcoming CVD, of vitamins A, C, E, carotene and conutrients also cancer; randomized exclusive supplementation of beta-carotene +/- vitamin A or E lack benefits except prostate cancer reduction by vitamin E, and overall cancer reduction by selenium; randomized intervention with synchronous rectification of vitamins A + C + E + B + minerals reduces CVD and counteracts precancerous lesions; high vitamin E supplements reveal potentials in secondary CVD prevention. Plasma values desirable for primary prevention: > or = 30 mumol/l lipid-standardized vitamin E (alpha-tocopherol/cholesterol > or = 5.0 mumol/mmol); > or = 50 mumol/l vitamin C aiming at vitamin C/vitamin E ratio > 1.3-1.5; > or = 0.4 mumol/l beta- (> or = 0.5 mumol/l alpha+ beta-) carotene.

CONCLUSIONS

In CVD vitamin E acts as first risk discriminator, vitamin C as second one; optimal health requires synchronously optimized vitamins C + E, A, carotenoids and vegetable conutrients.