Tocopherol Supplementation Research Articles

Identification of hepatic molecular mechanisms of action of alpha-tocopherol using global gene expression profile analysis in rats.

The recent discovery that vitamin E (VE) regulates gene activity at the transcriptional level indicates that VE may exert part of its biological effects by mechanisms which may be independent of its well-recognised antioxidant function. The objective of this study was the identification of hepatic vitamin E-sensitive genes and examination of the effects of VE on their corresponding biological endpoints. Two groups of male rats were randomly assigned to either a VE-sufficient diet or to a control diet deficient in VE for 290 days. High-density oligonucleotide microarrays comprising over 7000 genes were used to assess the transcriptional response of the liver. Differential gene expression was monitored over a period of 9 months, at four different time-points, and rats were individually profiled. This experimental strategy identified several VE-sensitive genes, which were chronically altered by dietary VE. VE supplementation down-regulated scavenger receptor CD36, coagulation factor IX and 5-alpha-steroid reductase type 1 mRNA levels while hepatic gamma glutamyl-cysteinyl synthetase was significantly up-regulated. Measurement of the corresponding biological endpoints such as activated partial thromboplastin time, plasma dihydrotestosterone and hepatic glutathione substantiated the gene chip data which indicated that dietary VE plays an important role in a range of metabolic processes within the liver.

Effects of Feeding Methods (Feed vs. Water) of Vitamin E on Growth Performance and Meat Quality of Broilers

This research was conducted to compare the effects of vitamin E (VE) when supplemented in either feed or water on the performance and meat quality of broilers. For a six-week feeding trial, a total of 330 broiler chicks were allotted to five treatments. The treatments were 1) 0 ppm VE, 2) 10 ppm VE in feed, 3) 20 ppm VE in feed, 4) 5 ppm VE in water and 5) 10 ppm VE in water. During the starter phase (0-3 weeks) chicks on non-supplemented groups grew slower (p<0.05) than the supplemented ones and the same trend was followed during the finisher (4-6 weeks) and overall period (0-6 weeks). The feed intake was significantly higher in feed supplemented groups as compared with water-supplemented groups and at higher levels as compared with lower levels of supplementation. The nutrient digestibility studies conducted after 15 and 35 days on the feeding trial showed that the digestibility of all nutrients was significantly (p<0.05) higher in supplemented groups than the non-supplemented one. The dressing percentage was higher in supplemented groups, when fed in feed and at higher levels when compared with their respective counterparts. Similar trends were noticed with respect to bone resistance. The calcium and phosphorus contents in tibia were also significantly (p<0.05) higher in supplemented, feed fed groups at higher levels than other groups. The TBARS values measured after 5 and 10 days of storage, which reflect the degree of oxidation, showed significantly lower levels in supplemented diets. The plasma and muscle vitamin E levels also showed a positive linear correlation with the levels supplemented both in feed and water. Overall it can be inferred that supplementation of VE was beneficial and there was not much difference observed when fed either in feed or water at the levels measured in the present study. (Asian-Aust. J. Anim. Sci. 2004. Vol 17, No. 9 : 1260-1265)

Profile of chicken cytokines induced by lipopolysaccharide is modulated by dietary alpha-tocopheryl acetate

Previously, we found that 25 to 50 IU/kg of dietary vitamin E (VE) had very different immunoregulatory effects than high VE levels (200 IU/kg), and we hypothesized that this difference was due to different cytokine profiles. Chicks were fed 0, 30, or 200 IU/kg supplemental VE and percentages of CD4+CD8-, CD4-CD8+, CD4+CD8+, and CD4-CD8- lymphocytes, and the ratio of CD4+/CD8+ lymphocytes was determined. The expression of chicken splenic interleukin-1beta (IL-1beta), myelomonocytic growth factor (MGF), interferon (IFN-gamma), and transforming growth factor-beta (TGFbeta) mRNA was determined by reverse transcription (RT)-PCR after intravenous injection of lipopolysaccharide (LPS). Due to a tendency for increased CD4-CD8+ lymphocytes at 30 IU/kg VE (P=0.072), the CD4+/CD8+ ratio was significantly lower for 30 IU/kg VE compared with 0 IU/kg VE (P=0.041). The VE dose of 200 IU/kg decreased the constitutive (prior to LPS) expression of TGFbeta. The LPS caused an increase in IL-1beta, MGF, and IFNgamma expression at all VE concentrations and had no effect on IL-2 and TGFbeta mRNA expression. Dietary VE decreased MGF mRNA (P=0.049) in a dose-dependent manner but had no effect on the expression of other cytokines. The decreased expression of MGF could explain the immunomodulatory effect of VE in inflammation.

Supplementing Hen Diets with Vitamins A and E Affects Egg Yolk Retinol and α-Tocopherol Levels

Laying hens were fed a basal diet supplemented with increasing levels of retinyl acetate and α-tocopheryl acetate to investigate the effects of vitamin A and E supplementation upon egg yolk retinol and tocopherol concentrations. The high concentration of added vitamin E caused a decline in egg production and poor feed conversion. Egg quality was not affected by vitamin A and E levels. Yolk retinol concentration was enhanced by added vitamin A, from 24.6 IU/g for eggs from the control group, to 33.6 and 37.7 IU/g of yolk when hens were fed 15,000 and 30,000 IU/kg of diet. Yolk α-tocopherol was significantly increased by dietary tocopherol supplementation, ranging from 10.9 μg/g (control group) to 160.6, 264.1, and 383.2 μg/g of yolk, respectively, when 200, 400 and 600 mg/kg of ration were added, respectively. Yolk α-tocopherol was increased by 24.9 and 44.0% with increasing vitamin A supplementation at 15,000 and 30,000 IU/kg of diet, respectively. When correlation coefficients and regression equations were calculated, it was found that yolk α-tocopherol decreased (P < 0.05) as supplemental vitamin A increased, indicating the adverse effect of dietary vitamin A on yolk tocopherol deposition. The nutritional value of eggs, related to retinol and tocopherol, can be improved by dietary manipulation of hens diet, but attention must be focused on their inter-relationship.

α-Tocopherol protects against diet induced atherosclerosis in New Zealand white rabbits

In this study, we asked the question "does alpha-tocopherol supplementation prevent an increase in total plasma cholesterol (TPC) concentration and reduce the deposition of cholesterol in arterial plaques of rabbits fed atherogenic diets?" Isocaloric diets containing 0.1% cholesterol to induce atherosclerosis were enriched in one of three fats: saturated fats (SAT), monounsaturated fats (MONO), or n-6 polyunsaturated fats (POLY). Half of each of the three diets were supplemented with 2,500 IU alpha-tocopherol/kg-diet. Unsupplemented diets contained 25 IU alpha-tocopherol/kg-diet. Rabbits supplemented with alpha-tocopherol had plasma alpha-tocopherol concentrations 10-fold higher and an average TPC concentration 31% lower, P = 0.017, than rabbits fed unsupplemented diets. Among the three fat-fed groups, the difference was greatest for the POLY fat fed group (54%, P = 0.041). POLY fat-fed rabbits without alpha-tocopherol supplementation had plasma HDL cholesterol concentrations that were less than half that of rabbits fed other fats, P < or = 0.0001. In general, differences in mean esterified artery cholesterol concentrations among the three fat-fed groups, with and without alpha-tocopherol supplementation, paralleled differences in TPC concentration among the groups. This study suggests that for rabbits fed high pharmacological doses of alpha-tocopherol, atherosclerosis can be diminished in situations where the plasma cholesterol concentrations are also significantly lower.

Effect of mixed tocopherols on ecNOS, SOD and PKC in leukocytes in human subjects

Epidemiological studies have shown that intake of vitamin E derived from food decreases the risk of cardiovascular disease. However, recent clinical studies revealed no beneficial effect of α-tocopherol alone on cardiac death. Absence of other tocopherols in these latter studies may explain the conflicting results. This study was designed to compare the effects of mixed tocopherols with α-tocopherol alone on endothelial constitutive nitric oxide synthase (ecNOS), superoxide dismutase (SOD) and protein kinase C (PKC) in human leukocytes, which are known to be involved in cardiovascular disease. Sixty-four subjects were randomized into three groups: α-tocopherol, mixed tocopherols, and controls. After 8 weeks of tocopherol supplementation, SOD activity in plasma, ecNOS activation and SOD protein expression in leukocytes were increased, and PKC activation in leukocytes was decreased. Mixed tocopherols had a more potent effect than α-tocopherol alone on ecNOS activation, which may be of importance for the beneficial effects of mixed tocopherols on leukocyte function and cardiovascular disease.

Tocopherol isoforms in parenteral lipid emulsions and neutrophil activation

Background and Aims: Tocopherol is a lipid-soluble anti-oxidant that exists in several isoforms. Patients on total parenteral nutrition depend on lipid emulsions for their tocopherol intake. In the present study, we analysed the content of tocopherol isoforms in various lipid emulsions. We also tested the hypothesis that immune-modulating effects of lipid emulsions could be attributed to different concentrations of α-tocopherol (α-toc) or peroxidation products. Method: α-, β-, γ- and δ-toc were measured in emulsions containing long-chain triglycerides (LCT), mixed long- and medium-chain triglycerides (LCT/MCT), structured lipids (SL), olive oil (OO) or fish oil (FO). As a measure for cellular activation, neutrophil membrane adhesion markers were assessed after exposure to two LCT/MCT emulsions that differ only in α-toc content. Results: Various emulsions differed widely in tocopherol contents, especially with respect to the α- isoform. The latter isomer also was subject to considerable degradation despite adequate storage conditions. The previously observed activation of neutrophils by LCT/MCT was not influenced by the increased concentration of α-toc or the decreased concentration of lipid peroxidation products in a new LCT/MCT emulsion. Conclusions: Tocopherol supplementation by parenteral lipid emulsions strongly depends on the lipid source and the storage lifetime of the emulsion. The effects of LCT/MCT on the immune system are not modulated by α-toc or by lipid peroxidation products.

Tocopherol supplementation reduces markers of thrombosis

Tocopherol supplementation reduces markers of thrombosis

Immunomodulatory effects of high-dose α-tocopherol acetate on mice subjected to sidestream cigarette smoke

Several recent epidemiological investigations raise serious questions about the health effects of high-dose supplements of Vitamin E (VE) in cigarette smokers. To examine these findings, a total of 96 C57BL/6 mice were randomly assigned to eight groups in a 2×4 factorial design (smoke vs. sham smoke and normal diet vs. 3 VE supplements). The mice were exposed to sidestream cigarette smoke (SSCS), at 0.4 mg total particulate matter/m 3 air, from standard research cigarettes (1R4)/day or filtered room air at 30 min/day, 5 days/week, for 9 weeks through a nose-only exposure chamber. The American Institute of Nutrition 93G purified rodent diet was modulated with 75 (regular diet, 1-fold), 1050 (15-fold), 5550 (75-fold), and 11 175 (150-fold) IU dl-α-tocopherol acetate (α-TA)/kg as VE supplementation and provided ad libitum at an average intake rate of 4.11 g diet/mouse/day. This result demonstrated that SSCS exposure results in lung dysfunction, as indicated by a decrease of pulmonary dynamic compliance ( C dyn) and increase of lung resistance ( R L), and body weight loss in mice fed with regular diet. These changes accompanied with increases of bronchoalveolar lavage (BAL) concentrations of cytokines interleukin (IL)-1β, IL-4 and IFN-γ, as well as hepatic lipid peroxidation. However, supplemental α-TA at the doses of ⩾1050 IU/kg diet prevented the SSCS-induced body weight loss and lung dysfunction. α-TA at ⩾5550 IU/kg significantly increased BAL levels of IL-2 and IL-4 in both the sham SSCS and the SSCS groups. Given at 5550 IU α-TA/kg, but not higher, mice elevated BAL IL-1β level if they were exposed to SSCS. Hepatic lipid peroxidation was decreased in a dose-dependent fashion with different α-TA supplements in both the sham SSCS and SSCS groups. Neither SSCS nor α-TA had an effect on lung permeability, BAL IL-6, splenic T and B lymphocyte proliferation and their T helper (Th)1 and Th2 cytokines measured among all groups. Data suggest that supplemental α-TA may be needed to counteract SSCS-induced oxidative stress, but that potential side effects introduced by high dosage of this synthetic compound should be considered.

Serum Vitamin E and Lipid-adjusted Vitamin E Assessment in Friedreich Ataxia Phenotype Patients and Unaffected Family Members

Friedreich ataxia (FA) is an autosomal recessive spinocerebellar syndrome with onset before age 25, characterized by progressive cerebellar ataxia, dysarthria, areflexia, sensory loss in lower limbs, pyramidal weakness, and Babinski signs (1). It is caused by an intronic expanded unstable GAA repeat in the frataxin gene (2) located on chromosome 9q13-q21 (3). Investigating five Tunisian families with typical FA phenotype, Ben Hamida et al. (4) had excluded linkage to the locus of FA in two families and provided evidence for genetic heterogeneity of the disease. Patients belonging to families not linked to the locus of FA showed very low serum vitamin E (VE) with no evidence of lipid malabsorption. The role of VE in maintaining human nervous system function is established, and the role of VE deficiency in neurologic disorders of a-β-lipoproteinemia and biliary atresia is well accepted (5)(6). Several reports (4)(7)(8)(9)(10) have described patients with a progressive spinocerebellar syndrome associated with very low serum VE in the absence of fat malabsorption or a-β-lipoproteinemia. This disease, termed ataxia with VE deficiency (AVED), is inherited with an autosomal recessive pattern (3)(4). The abnormal gene was mapped to chromosome 8q (11) and identified as the gene encoding for α-tocopherol transfer protein (α-TTP) (12). Because it is difficult to distinguish on the basis of clinical features between AVED patients in whom VE supplementation may be beneficial (7)(13)(14) and those with classic FA, we assessed serum VE, total cholesterol (TC), and triglycerides (TGs) in our patients with FA clinical phenotype …

Antioxidant effects of alpha- and gamma-carboxyethyl-6-hydroxychromans.

Carboxyethyl-6-hydroxychromans (CEHC), the major metabolites of both tocopherols (Toc) and tocotrienols (Toc-3), have been found in human plasma. In the present study, the antioxidant properties of alpha- and gamma-CEHC were measured and compared with alpha- and gamma- tocopherols. Following results were obtained: (1)alpha- and gamma-CEHC have the same reactivities toward radicals and exert the same antioxidant activities against lipid peroxidation in organic solution as the corresponding parent tocopherols respectively; (2) the partition coefficient decreased in the order alpha-Toc (3.36) > gamma-Toc (3.14) > alpha-CEHC (2.26) > pentamethyl-6-chromanol (1.92) > gamma-CEHC (1.83) > 0 > Trolox (-0.97); (3) alpha- and gamma-CEHC scavenge aqueous radicals more efficiently but they inhibit the lipid peroxidation within the membranes less efficiently than the corresponding alpha- and gamma-Toc, respectively; (4) alpha-CEHC inhibits the oxidation synergistically with ascorbate; and (5) alpha- and gamma-CEHC reduce Cu(II) to give Cu(I) and corresponding quinones as major product, but the prooxidant effect of CEHC in the presence of cupric ion was small. These results imply that CEHC may act as an antioxidant in vivo especially for those who take tocopherol supplement.

Effect of supplemental vitamin E on the color and case-life of top loin steaks and ground chuck patties in modified atmosphere case-ready retail packaging systems

Retail packages ( n=384; 24 of each product in each treatment by storage combination) of ground chuck patties (GC) and top loin steaks (TL) were used to evaluate effects of dietary supplementation of Vitamin E (VITE) to cattle on product performance when packaged in a modified atmosphere case-ready packaging system (MAP). Products from control (CON) animals and cattle fed 500 IU animal −1 day −1 for 124 days were evaluated. Color properties, lipid oxidation, and α-tocopherol concentration were measured. Analysis revealed a higher concentration of α-tocopherol in VITE samples compared with control samples for top loin steaks and ground chuck patties. In comparison to CON cuts, maximum display life was improved by 3 and 0.9 days with VITE for top loin steaks and ground chuck patties, respectively. This study suggests that VITE supplementation would be beneficial in improving lipid and color stability of beef products stored in high oxygen MAP packaging systems.

Eggs and poultry meat as tocopherol sources in dependence on tocopherol supplementation of poultry diets

One feeding trial with broilers and three feeding experiments with layers were carried out to investigate the influence of various vitamin E supplementations on α-tocopherol concentration of foods of poultry origin. Vitamin E content of basal diets amounted to ≈20 mg per kg feed; 0, 100, 1000, 10 000 and 20 000 mg vitamin E per kg feed were added. Broilers were fed for 30 days and slaughtered, layers were kept for one laying year (13×28 days), eggs were collected daily. Vitamin E concentration was determined in muscle (breast, legs), liver, fat and eggs by HPLC. Tocopherol concentration increased with vitamin E supplementation in all samples. The highest tocopherol concentration was measurement in egg yolk (254.9) followed by liver (44.8) and muscle (12.2 mg/100 g). Vitamin E supply of poultry feed depends on costs of vitamin E and financial benefits for the farmer.

Relationship Between the Level of Dietary Vitamin E and the Immune Response of Broiler Chickens

The relationship between the dietary level of vitamin E (VE) and the immune response of broilers was studied in three experiments. Immunity was assessed as antibody production to infectious bronchitis virus (IBV), SRBC, and Brucella abortus (BA) antigens, mitogenic response to phytohemagglutinin A (PHA) and concanavalin A (Con A), cutaneous basophil hypersensitivity (CBH) to PHA, and lipopolysaccharide induction of acute-phase proteins (APP) and heterophilia. A range of VE (0, 10, 17.5, 25, 37.5, 50, 100, and 200 IU/kg) levels were supplemented to a basal diet (corn-soy) containing 10.2 IU of VE/kg. We found a dose-dependent increase in antibody production in response to attenuated IBV between 0 and 25 IU/kg of supplemented VE and no further increase at higher levels. Antibody levels to SRBC were higher in birds supplemented with 50 IU of VE/kg compared to those supplemented with 0 or 200 IU/kg of VE. Antibody production in response to BA antigens was not influenced by VE. Mitogenic responses were suppressed by supplemented VE in Experiment 1 for PHA (25 IU/kg diet) and Con A (25 and 50 IU/kg diets). CBH and APP levels were not affected by VE. Heterophilia was lowest at 50 IU/kg 6 h after lipopolysaccharide injection (Experiment 1). Our study showed that moderate (25 to 50 IU/kg) levels of VE supplementation were most immunomodulatory and that high levels were less effective.

Effects of oral vitamin E supplementation during late gestation in beef cattle that calved in late winter and late summer.

To determine effects of breed and oral vitamin E supplementation during late gestation on serum vitamin E and IgG concentrations in beef cows that calved in late winter and late summer and in neonatal calves. 73 Angus and 43 Hereford primiparous and multiparous cows and their calves. Cows in groups that were homogeneous regarding breed and age distribution were randomly allotted to groups that were orally supplemented (n = 59) or not supplemented (57) with vitamin E beginning 30 days prior to onset of 65-day calving seasons. Supplemental vitamin E was provided in a vitamin-mineral mix offered free-choice until parturition. Cows that calved in late winter and were supplemented orally with vitamin E had higher serum vitamin E concentrations at calving and after calving than did unsupplemented cows; differences between groups before calving were not significant. Calves from supplemented multiparous cows had higher vitamin E concentrations than did calves from unsupplemented cows. Winter-born calves from supplemented Hereford cows had heavier 205-day adjusted weaning weights than did winter-born calves from unsupplemented Hereford cows. Supplementation did not affect vitamin E or IgG concentrations in the herd that calved in late summer and did not affect calf growth. Oral vitamin E supplementation during late gestation may be economically beneficial in certain cow-calf operations in which late-gestation cows are consuming stored forages.

Failure to demonstrate a major anti-inflammatory effect with alpha tocopherol supplementation (400 IU/day) in normal subjects

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No beneficial effect of vitamin E on selective immunological responses in early stage of collagen-induced murine arthritis

We investigated whether vitamin E (VE) supplementation alleviates collagen-induced arthritis in its stages by altering immune functions in DBA/1J mice. Mice were divided into 4 groups; control (VE 30 IU/kg in diet), A-VE0, A-VE30 and A-VE500 (animals with induced arthritis given VE 0, VE 30, VE 500 IU/kg in diet respectively). Arthritis was induced with Type II Collagen (TIIC). The extent of arthritis in the joint did not decline in neither A-VE0 nor A-VE500 groups compared with A-VE30. The proliferation of splenocytes stimulated with ConA was suppressed in both A-VE0 and A-VE500 groups. The production of Th1 cytokine stimulated with TIIC was increased in both A-VE0 and A-VE500 groups, but production of Th2 cytokine was not changed. Our observations suggest that VE supplementation does not always improve the progress of arthritis. The influence of VE on cytokine balance in autoimmune (Th1 predominant) arthritis should be further investigated.

Association between alpha-tocopherol, gamma-tocopherol, selenium, and subsequent prostate cancer.

Selenium and alpha-tocopherol, the major form of vitamin E in supplements, appear to have a protective effect against prostate cancer. However, little attention has been paid to the possible role of gamma-tocopherol, a major component of vitamin E in the U.S. diet and the second most common tocopherol in human serum. A nested case-control study was conducted to examine the associations of alpha-tocopherol, gamma-tocopherol, and selenium with incident prostate cancer. In 1989, a total of 10,456 male residents of Washington County, MD, donated blood for a specimen bank. A total of 117 of 145 men who developed prostate cancer and 233 matched control subjects had toenail and plasma samples available for assays of selenium, alpha-tocopherol, and gamma-tocopherol. The association between the micronutrient concentrations and the development of prostate cancer was assessed by conditional logistic regression analysis. All statistical tests were two-sided. The risk of prostate cancer declined, but not linearly, with increasing concentrations of alpha-tocopherol (odds ratio (highest versus lowest fifth) = 0.65; 95% confidence interval = 0.32--1.32; P(trend) =.28). For gamma-tocopherol, men in the highest fifth of the distribution had a fivefold reduction in the risk of developing prostate cancer than men in the lowest fifth (P:(trend) =.002). The association between selenium and prostate cancer risk was in the protective direction with individuals in the top four fifths of the distribution having a reduced risk of prostate cancer compared with individuals in the bottom fifth (P(trend) =.27). Statistically significant protective associations for high levels of selenium and alpha-tocopherol were observed only when gamma-tocopherol concentrations were high. The use of combined alpha- and gamma- tocopherol supplements should be considered in upcoming prostate cancer prevention trials, given the observed interaction between alpha-tocopherol, gamma-tocopherol, and selenium.

Alpha tocopherol supplementation decreases serum C-reactive protein and monocyte interleukin-6 levels in normal volunteers and type 2 diabetic patients

Type 2 diabetic subjects have an increased propensity to premature atherosclerosis. Alpha tocopherol (AT), a potent antioxidant, has several anti-atherogenic effects. There is scanty data on AT supplementation on inflammation in Type 2 diabetic subjects. The aim of the study was to test the effect of RRR-AT supplementation (1200 IU/d) on plasma C-reactive protein (CRP) and interleukin-6 (IL-6) release from activated monocyte in Type 2 diabetic patients with and without macrovascular complications compared to matched controls. The volunteers comprised Type 2 diabetic subjects with macrovascular disease (DM2-MV, n = 23), Type 2 diabetic subjects without macrovascular complications (DM2, n = 24), and matched controls (C, n = 25). Plasma high sensitive CRP (Hs-CRP) and Monocyte IL-6 were assayed at baseline, following 3 months of supplementation and following a 2 month washout phase. DM2-MV subjects have elevated HsCRP and monocyte IL-6 compared to controls. AT supplementation significantly lowered levels of C-reactive protein and monocyte interleukin-6 in all three groups. In conclusion, AT therapy decreases inflammation in diabetic patients and controls and could be an adjunctive therapy in the prevention of atherosclerosis.

Effect of vitamin E supplementation on antibody levels against malondialdehyde modified LDL in hyperlipidemic hamsters.

The aim of this work was to investigate the effect of vitamin E (VE) supplementation on the formation of autoantibodies against oxidized low density lipoproteins (LDL) in a hyperlipidemic animal model. Thirty-four male hamsters (Mesocricetus auratus), (4 weeks old) were divided into three groups: Group A (n=9) was fed with standard rodent chow; group B (n=13) was fed with a standard rodent chow plus 2% cholesterol and 10% butter and group C (n=12) was fed with the same diet plus 0.2% (w/w) VE. Blood samples were collected by intracardiac puncture and antibody levels were determined in each animal at 4 weeks of age and after 20 weeks of experimental diet. A modified ELISA technique was used to analyze the modulation of autoantibody titers against an epitope of oxidized LDL in serum samples. Antigens prepared for the ELISA tests were characterized using spectrofluorimetry. Serum VE levels were determined in the lipidic fractions by HPLC. The groups fed with cholesterol-fat enriched diet presented a three-fold increase in total serum cholesterol and two-fold increase in serum triglycerides compared to the control group. VE supplementation played no role in serum cholesterol and serum triglyceride concentrations but led to a decreased autoantibody (anti-LDL-malondialdehyde) formation (P<0.05). Our results show that VE supplementation leads to a lower production of autoantibodies against oxidized LDL, suggesting a protective effect of VE against in vivo oxidation of LDL particles, in a dose-dependent manner.