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At least 19 recordsLinked to original sources
PubMed1996

Blood selenium, vitamin E, vitamin A, and beta-carotene concentrations and udder health, fertility treatments, and fertility.

We investigated the activity of glutathione peroxidase in whole blood; concentrations of vitamin E, vitamin A, and beta-carotene in serum; SCC; udder bacterial infections and the incidence of clinical mastitis; fertility treatments; and the success of first AI of 511 dairy cows for 1 yr. The mean Se content in whole blood and the concentrations of vitamin E, vitamin A, and beta-carotene concentrations in serum were 191 micrograms/L, 5.9 mg/L, 0.39 mg/L, and 12.9 mg/L, respectively. An increase in Se concentration in whole blood was associated with a decrease in all infections, including infections by Staphylococcus aureus, Actinomyces pyogenes, and Corynebacterium spp. (-17.7, -31.7, and -70.6%, respectively). There was no association among the different infections or SCC and concentrations of vitamin E, vitamin A, or beta-carotene, but an association existed between vitamin A concentration and SCC. The lower Se concentration in whole blood did not increase incidence of clinical mastitis. The Se concentration in whole blood (200 micrograms/L) was accepted as a target value to optimize udder health. The incidence of fertility disorders (anestrus, subestrus, cystic ovaries, or delayed ovulation) was 34.4%. The pregnancy rate following first insemination was 48.6%. No significant association was observed among Se in whole blood; concentrations of total vitamin E, vitamin A, or beta-carotene in serum; and fertility disorders or success of first AI.

Animals↗
PubMed1999

Relation of consumption of vitamin E, vitamin C, and carotenoids to risk for stroke among men in the United States.

BACKGROUND: Antioxidants increase the resistance of low-density lipoprotein to oxidation and may thereby reduce risk for atherosclerosis. OBJECTIVE: To determine whether intake of vitamin E, vitamin C, or carotenoids predict risk for total or ischemic stroke. DESIGN: Prospective observational study. SETTING: The Health Professionals Follow-up Study. PARTICIPANTS: 43,738 men 40 to 75 years of age who did not have cardiovascular disease or diabetes. MEASUREMENTS: Repeated and validated dietary assessments were done by using a self-administered 131-item food-frequency questionnaire, which included questions on dose and duration of vitamin supplement use. The follow-up period was 8 years. RESULTS: A total of 328 strokes occurred: 210 ischemic, 70 hemorrhagic, and 48 unclassified. After adjustment for age, smoking, hypertension, hypercholesterolemia, body mass index, physical activity, parental history of myocardial infarction, alcohol consumption, and total energy intake, the relative risk for ischemic stroke in the top quintile of vitamin E intake (median, 411 IU/d) compared with the bottom quintile (5.4 IU/d) was 1.18 (95% CI, 0.77 to 1.82). The relative risk for ischemic stroke in the top quintile of vitamin C intake (1167 mg/d) compared with the bottom quintile (95 mg/d) was 1.03 (CI, 0.66 to 1.59). Results for total stroke were similar. Associations of vitamin intake with hemorrhagic stroke were also nonsignificant, but the CIs were wide. Neither dose nor duration of vitamin E or vitamin C supplement use was related to risk for total or ischemic stroke. The relative risk for ischemic stroke was 1.16 (CI, 0.81 to 1.67) in men using 250 IU or more of vitamin E supplementation per day compared with men who used no vitamin E supplements and was 0.93 (CI, 0.60 to 1.45) in men using 700 mg or more of vitamin C supplementation per day compared with men who used no vitamin C supplements. A significant inverse relation between lutein intake and risk for ischemic stroke was seen but was not independent of other dietary factors. CONCLUSIONS: Vitamin E and vitamin C supplements and specific carotenoids did not seem to substantially reduce risk for stroke in this cohort. Modest effects, however, cannot be excluded.

Adult↗
PubMed1988

Vitamin E, vitamin B-6, vitamin B-12, and folate status of gastric bypass surgery patients.

The vitamin E, vitamin B-6, vitamin B-12, and folate status of 22 gastric bypass subjects aged 23 to 60 years was evaluated before surgery and at 6 and 12 months after surgery. Before surgery, 77% of subjects had adequate plasma vitamin E levels; 36%, adequate plasma pyridoxal phosphate levels; 100%, adequate plasma vitamin B-12 levels; and 45%, adequate plasma folate levels. The food intake of all subjects was sharply reduced after surgery. After surgery, subjects were classified into three vitamin supplement groups on the basis of average daily vitamin supplement intake. Subjects taking higher levels of supplements containing the vitamins in question had significantly higher plasma concentrations of the vitamins than those taking low or moderate levels. The mean plasma vitamin values in the moderate supplement group were indicative of adequate status for all vitamins, but plasma vitamin B-12 levels at 12 months post-surgery were significantly lower than pre-surgery levels. In the low supplement group, mean plasma vitamin levels were in or near marginal or deficient ranges. The majority of subjects consuming supplements of vitamin E, vitamin B-6, and folate near the US RDA maintained normal vitamin status. Subjects taking more than 100 micrograms vitamin B-12 daily had adequate vitamin B-12 status. Significant correlations (r = .67 to .94) were observed between vitamin supplement levels and the respective plasma vitamin concentrations.

Adult↗
PubMed2001

Individual and synergistic antioxidative actions of melatonin: studies with vitamin E, vitamin C, glutathione and desferrioxamine (desferoxamine) in rat liver homogenates.

The pharmacological effects of melatonin, vitamin E, vitamin C, glutathione and desferrioxamine (desferoxamine) alone and in combination on iron-induced membrane lipid damage in rat liver homogenates were examined by estimating levels of malondialdehyde and 4-hydroxyalkenals (MDA+4-HDA). Individually, melatonin (2.5-1600 microM), vitamin E (0.5-50 microM), glutathione (100-7000 microM) and desferrioxamine (1-8 microM) inhibited lipid peroxidation in a concentration-dependent manner. Vitamin C had both a pro-oxidative (25-2000 microM) and an antioxidative (2600-5000 microM) effect. The IC50 (concentration that reduces damage by 50%) values were 4, 10, 426, 2290 and 4325 microM for vitamin E, desferrioxamine, melatonin, glutathione and vitamin C, respectively. The synergistic actions of melatonin with vitamin C, vitamin E, and glutathione were systematically investigated. When melatonin was combined with vitamin E, glutathione, or vitamin C, the protective effects against iron-induced lipid peroxidation were dramatically enhanced. Even though melatonin was added at very low concentrations, it still showed synergistic effects with other antioxidants at certain concentrations. Furthermore, melatonin not only reversed the pro-oxidative effects of vitamin C, but its efficacy in reducing lipid peroxidation was improved when it was combined with pro-oxidative concentrations of vitamin C. The results provide new information in terms of the possible pharmacological use of the combination of melatonin and classical antioxidants to treat free radical-related conditions.

Animals↗
PubMed1994

Radical exchange reactions between vitamin E, vitamin C and phospholipids in autoxidizing polyunsaturated lipids.

Antioxidant reactions of mixtures of vitamin E, vitamin C and phospholipids in autoxidizing lipids at 90 degrees C have been studied by ESR spectroscopy. When the phospholipid contained a tertiary amine (e.g. phosphatidylcholine), the vitamin C and the vitamin E radicals were successively observed as these two vitamins were sequentially oxidised during lipid oxidation. In the presence of the primary amine contained in phosphatidylserine, the vitamin E oxidation was delayed for a few hours. In this case neither the vitamin C, nor the vitamin E radicals but a nitroxide radical derived from the phospholipid was observed. Similar results to those obtained with PS were obtained in the presence of either phosphatidylethanolamine or soybean lecithin. The participation in the radical reactions of phospholipids possessing a primary amine can therefore explain the synergistic effect of these phospholipids in a mixture of vitamins E and C.

Ascorbic Acid↗
PubMed1987

Effects of vitamin E, vitamin B2 and selenite on DNA single strand breaks induced by sodium chromate (VI).

The effects of vitamin E, vitamin B2 and selenite on DNA single strand breaks induced by Na2CrO4 were examined by alkaline elution. Incubation of Chinese hamster V-79 cells with alpha-tocopherol succinate (vitamin E) for 24 h prior to exposure to Na2CrO4 resulted in a decrease of DNA breaks produced by this compound. However, similar pretreatment with riboflavin (vitamin B2) or Na2SeO3 resulted in an enhanced formation of breaks induced by Na2CrO4. Pretreatment with Na2SeO3 resulted in increased levels of glutathione in these cells while levels of glutathione remained the same with vitamin E or vitamin B2. These results suggest that Na2CrO4 induced DNA breaks appear to be mediated by the formation of free radicals and/or cellular reductive metabolism.

Animals↗
PubMed2000

Chromate-induced human erythrocytes haemoglobin oxidation and peroxidation: influence of vitamin E, vitamin C, salicylate, deferoxamine, and N-ethylmaleimide.

In order to attenuate or to prevent chromate-induced human erythrocytes injury, the influence of vitamin E, vitamin C, salicylate, deferoxamine, and N-ethylmaleimide on chromate-induced human erythrocytes haemoglobin oxidation and peroxidation were investigated. It was observed that pretreatment of human erythrocytes with vitamin E (20 microM), vitamin C (1 mM), salicylate (3 mM), and deferoxamine (4 mM) significantly increased (P=0.0001) chromate-induced human erythrocytes haemoglobin oxidation in a time dependent manner, while it was significantly decreased (P=0.0001) by pretreatment with N-ethylmaleimide (1 mM). In contrast, pretreatment of human erythrocytes with deferoxamine (4 mM) immediately inhibited (P=0.0001) chromate-induced human erythrocytes peroxidation, while it was significantly increased (P=0.0001) by pretreatment with N-ethylmaleimide (1 mM) during the first 4 h of cells exposition to chromate. For time periods superior to 6 h pretreatment with N-ethylmaleimide (1 mM) significantly decreased (P=0.0001) chromate-induced human erythrocytes peroxidation. It was concluded that care must be taken as these drugs are used to prevent against toxicity induced by chromium(VI) compounds.

Ascorbic Acid↗
PubMed1995

Increase of singlet oxygen protection of erythrocytes by vitamin E, vitamin C, and beta carotene intakes.

Substantial evidence supports the theory that free radicals, especially oxygen radicals, are involved in the process of aging. The human organisms have two ways to fight them: an enzymatic way with enzymatic intervention like superoxide dismutase, catalase... and a chemical way with the intervention of scavengers such as vitamins, cysteine, methionine, gluthatione... The aim of this work was to determine that an intakes of vitamins association: vitamin E, vitamin C and beta carotene induce an increase of singlet oxygen protection of erythrocytes' subjects. The method was based on the haemolytic effect of singlet oxygen which is generated by irradiation of hematoporphyrine at 365 nm, in 22 p. cent suspension of erythrocytes' subjects. Results show that a supply of beta carotene (15 or 30 mg/day), vitamin E (15 mg/day) and vitamin C (30 mg/day) involves an increase of singlet oxygen protection of erythrocytes of subjects. This protection appears very quickly after 15 days of treatment.

Administration, Oral↗
PubMedDate not supplied

[E-vitamin activity of vitamin E derivatives with experimental encephalomalacia in chicks].

When adding pharmacopoeian alpha-tocopherylacetate, short-chain alpha-tocopherylacetate, alpha-tocopherylquinine, short-chain alpha-tocopherylquinone and alpha-tocopheronolactone to E-avitaminotic rations pharmacopoeian alpha-tocopherylacetate and alpha-tocopheronolactone manifest the highest E-vitamin activity in preventing encephalomalacia in chickens. The action of alpha-tocopheronolactone is not directly associated with changes in the content of vitamin E and ubiquinone in the brain and liver tissues. All the studied derivatives are effective in increasing resistance of erythrocytes to osmotic hemolysis. The data obtained evidence for a nonspecific function of vitamin E in preventing alimentary encephalomalacia in chickens as well as for the absence of disturbances in ubiquinone metabolism under conditions of the E-hypovitaminosis experimental model.

Animals↗
PubMed1995

Effect of vitamin E, vitamin C and beta-carotene on LDL oxidation and atherosclerosis.

OBJECTIVE: The oxidative modification of low density lipoprotein (LDL) may be an early step in atherogenesis. Furthermore, evidence of oxidized LDL has been found in vivo. The most persuasive evidence shows that supplementation of some animal models with antioxidants slows atherosclerosis. The purpose of this review is to examine the roles that vitamin E, vitamin C and beta-carotene may play in reducing LDL oxidation. DATA SOURCES: English language articles published since 1980, particularly from groups active in this field of research. STUDY SELECTION: In vitro, animal, and human studies on antioxidants, LDL oxidation, and atherosclerosis were selected. DATA SYNTHESIS: Vitamin E has shown the most consistent effects with regard to LDL oxidation. Beta-carotene appears to have only a mild or no effect on oxidizability. Ascorbate, although it is not lipophilic, can also reduce LDL oxidative susceptibility. CONCLUSIONS: LDL oxidizability can be reduced by antioxidant nutrients. However, more research is needed to establish their utility in the prevention of coronary artery disease.

Animals↗
PubMed2000

Long-term effects of vitamin E, vitamin C, and combined supplementation on urinary 7-hydro-8-oxo-2'-deoxyguanosine, serum cholesterol oxidation products, and oxidation resistance of lipids in nondepleted men.

We studied the long-term effects of vitamins E and C and their combination on lipid peroxidation in vivo and in vitro. The Antioxidant Supplementation in Atherosclerosis Prevention (ASAP) trial is a double-masked placebo-controlled randomized clinical trial to study the effects of vitamin C (500 mg of slow release ascorbate per day), vitamin E (182 mg of RRR-alpha-tocopherol acetate per day), and the combination of both antioxidants. Lipid peroxidation measurements were carried out for 48 male participants at entry and at 12 and 36 months. Compared with placebo, vitamin E and the vitamin combination increased plasma lipid-standardized alpha-tocopherol during the first 12 months by 68.2% and 65.2% (P:<0. 001 for both), respectively, and reduced serum 7beta-hydroxycholesterol by 50.4% (P:=0.013) and 44.0% (P:=0.041), respectively. The net change of lipid standardized alpha-tocopherol was 63.8% after 36 months of vitamin E supplementation and 43.3% for the combination. Vitamin C supplementation elevated plasma total ascorbate level by 30.1% (P:=0.043) in 12 months and by 91.1% (P:=0. 001) in 36 months. Neither vitamin E, vitamin C, nor the combination influenced the urinary excretion rate of 7-hydro-8-oxo-2'-deoxyguanosine or the antioxidative capacity of plasma. Vitamin E and the combination of vitamins E and C enhanced the oxidation resistance of isolated lipoproteins and total serum lipids. Our data indicate that long-term supplementation of nondepleted men with a reasonable dose of vitamin E alone or in combination with slow release vitamin C reduces lipid peroxidation in vitro and in vivo, whereas a relatively high dose of vitamin C alone does not.

8-Hydroxy-2'-Deoxyguanosine↗
PubMed2002

Photoprotective potential of lycopene, beta-carotene, vitamin E, vitamin C and carnosic acid in UVA-irradiated human skin fibroblasts.

The photoprotective potential of the dietary antioxidants vitamin C, vitamin E, lycopene, beta-carotene, and the rosemary polyphenol, carnosic acid, was tested in human dermal fibroblasts exposed to ultraviolet-A (UVA) light. The carotenoids were prepared in special nanoparticle formulations together with vitamin C and/or vitamin E. Nanoparticle formulations, in contrast to dimethylsulphoxide, stablized lycopene in the cell culture medium and allowed efficient cellular uptake. The presence of vitamin E in the formulation further increased the stability and cellular uptake of lycopene. UVA irradiation of the human skin fibroblasts led to a 10-15-fold rise in metalloproteinase 1 (MMP-1) mRNA. This rise was suppressed in the presence of low microM concentrations of vitamin E, vitamin C, or carnosic acid but not with beta-carotene or lycopene. Indeed, in the presence of 0.5-1.0 microM beta-carotene or lycopene, the UVA-induced MMP-1 mRNA was further increased by 1.5-2-fold. This increase was totally suppressed when vitamin E was included in the nanoparticle formulation. Heme-oxygenase 1 (HO-1) mRNA expression was strongly induced by UVA irradiation but none of the antioxidants inhibited this effect at the concentrations used in this study. Indeed, beta-carotene or lycopene (0.5-1.0 microM) led to a further 1.5-fold rise in the UVA-induced HO-1 mRNA levels. In conclusion, vitamin C, vitamin E, and carnosic acid showed photoprotective potential. Lycopene and beta-carotene did not protect on their own but in the presence of vitamin E, their stability in culture was improved and the rise in MMP-1 mRNA expression was suppressed, suggesting a requirement for antioxidant protection of the carotenoids against formation of oxidative derivatives that can influence the cellular and molecular responses.

Abietanes↗
PubMedDate not supplied

Copper status in rats fed diets supplemented with either vitamin E, vitamin A, or beta-carotene.

Copper status was measured in rats fed copper-adequate, purified diets supplemented with either vitamin E (250 IU/kg), vitamin A (40,000 IU/kg), or beta-carotene (2 g/kg). It was hypothesized that the extra intake of the antioxidants would spare vitamin C resulting in a decreased copper status as shown previously after supplementation with vitamin C. A significant increase in plasma ascorbate concentration was observed after beta-carotene supplementation, but not after supplemental vitamin E or vitamin A. Extra intake of either beta-carotene or vitamin A slightly, but significantly, raised plasma copper concentrations. Beta-carotene also slightly raised liver copper concentration. Supplemental vitamin E had no effect on plasma and liver copper concentrations. It is concluded that the observed relatively small effects of supplemental vitamin A and beta-carotene on copper status in rats are not mediated by changes in plasma vitamin C concentration.

Animals↗
PubMed2003

Levels of plasma vitamin E, vitamin C, TBARS, and cholesterol in male patients with colorectal tumors.

Vitamin E and vitamin C are involved in the defense of the body against free radical and reactive oxygen molecule induced damage. The best characterized biological damage caused by radicals is known as lipid peroxidation. Free radical formation is known to play a major role in the development of cancer. In this study, we measured plasma levels of thiobarbituric acid reactive substances (TBARS) as a marker of lipid peroxidation, cholesterol, and vitamins E and C as antioxidants in male patients with colorectal tumors (n = 20, 54.5 +/- 8.3 years). The patients had significantly higher plasma TBARS levels than age-matched healthy subjects (p < 0.001). Plasma vitamin C levels were significantly lower in the patients compared to the healthy subjects (p < 0.001). On the other hand, plasma vitamin E levels in the patients were similar to those of healthy subjects. Plasma cholesterol levels were also found to be significantly elevated in patients with colorectal tumors (p < 0.001). Our results suggest that there is an imbalance between oxidant and antioxidant status in tumor genesis.

Antioxidants↗
PubMed1992

Rates of interactions of superoxide with vitamin E, vitamin C and related compounds as measured by chemiluminescence.

The rate constants for the interactions of superoxide with vitamin E (alpha-tocopherol), vitamin C (ascorbic acid) and their related compounds have been measured by a chemiluminescence method. A strong chemiluminescence of a constant intensity was observed when xanthine oxidase was added to an aqueous solution of hypoxanthine and a Cypridina luciferin analog, 2-methyl-6-phenyl-3-7-dihydroimidazo[1,2-a]pyrazin-3-one (CLA). Vitamin E, vitamin C and their related compounds competed with CLA to react with superoxide and reduced the chemiluminescence intensity. From a kinetic analysis of the effect of addition of these compounds on the chemiluminescence intensity, the rate constants for their interactions with superoxide were measured at 25 degrees C and pH 7.8. The rate constants were obtained as 3.3 x 10(5) and 1.7 x 10(4) M-1 s-1 for ascorbate and 2-carboxy-2,5,7,8-tetramethyl-6-chromanol, respectively, and also as 4.9 x 10(3) and 4.5 x 10(3) M-1 s-1 for alpha-tocopherol incorporated into soybean and dimyristoyl phosphatidylcholine liposomal membranes, respectively. It has been shown that this method is a sensitive and a quick method which can be applied for measurement of the reactivities of various natural and synthetic compounds toward superoxide. In addition it has been shown that this method can also be applied to the heterogeneous system as well as homogeneous solution, which makes it more versatile and useful for the study in biochemistry.

Ascorbic Acid↗
PubMed2000

Vitamin E, vitamin C, and exercise.

Exercise increases the generation of oxygen free radicals and lipid peroxidation. Strenuous exercise in a person who is unconditioned or unaccustomed to exercise will induce oxidative damage and result in muscle injury. However, aerobic exercise training strengthens the antioxidant defense system by increasing superoxide dismutase. Vitamin C and, especially, vitamin E are shown to decrease the exercise-induced increase in the rate of lipid peroxidation. No ergogenic effects of either vitamin C or E have been shown. Vitamin E was shown to significantly increase circulating neutrophils in older, but not younger, subjects performing eccentric exercise that causes an increase in skeletal muscle damage. In addition to its effect in augmenting the neutrophil response to eccentric exercise, vitamin E causes a greater increase in circulating creatine kinase activity, perhaps indicating increased skeletal muscle repair. Increased vitamin E intake has been associated with enhanced glucose tolerance and insulin action as well as improved lipoprotein status. Future research should examine the combined effects of exercise training and vitamins E and C on these health-related outcomes.

Adult↗
PubMed2001

Comparison of antioxidant efficacy of vitamin E, vitamin C, vitamin A and fruits in coronary heart disease: a controlled trial.

OBJECTIVE: To determine the efficacy of various antioxidant vitamins and a major dietary source of antioxidants (fruits) we performed a randomized controlled trial. METHODS: 175 successive patients with coronary heart disease (CHD) presenting to our centre were recruited and using a Latin-square design divided into five groups of 35 each. The groups were matched for age, lifestyle and dietary variables, clinical diagnosis and drug treatment status. None of the patients was on lipid-lowering drugs. Supplemental vitamins were stopped for one month before study began and American Heart Association Step II dietary advice was given to all. At baseline, total cholesterol, triglycerides, HDL and LDL cholesterol and lipid peroxide measured as thiobarbaturic acid reactive substances (TBARS) were determined. Group I received placebo capsules; Group II vitamin E 400 units/day; Group III vitamin C 1,000 mg; Group IV vitamin A 25,000 IU; Group V received 400 gm of fruit daily. Lipids and lipid peroxide levels were determined at 30 days follow-up. RESULTS: Response rate in various groups varied form 86% to 91%. No significant changes in total, HDL, LDL cholesterol and triglyceride levels were seen in Groups I, II, III and IV (paired t-test p > 0.05). In Group V there was a significant decrease in total cholesterol (-7.8 +/- 11.1%), and LDL cholesterol (-11.2 +/- 25.4%) and increase in HDL cholesterol (+12.9 +/- 20.1%) (paired t-test p < 0.01). Lipid peroxide levels decreased significantly in all the treatment groups (p < 0.01). This decrease was the highest in Group II (vitamin E; -36.4 +/- 17.7%) as compared to Group III (vitamin C -19.8 -/+ 10.8%); Group IV (vitamin A -5.4 +/- 17%) and Group V (fruits -13.1 +/- 12.0%). CONCLUSIONS: All the antioxidant vitamins and fruits significantly decrease lipid peroxide levels and oxidant load in CHD patients. However, fruits are the best choice as they also favourably modify the lipid profile.

Antioxidants↗