PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “VITAMIN E”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 37 records · Page 2Linked to original sources
PubMed2005

Intake of vitamin E, vitamin C, and carotenoids and the risk of Parkinson's disease: a meta-analysis.

We studied the effect of vitamin C, vitamin E, and beta carotene intake on the risk of Parkinson's disease (PD). We did a systematic review and meta-analysis of observational studies published between 1966 and March 2005 searching MEDLINE, EMBASE, and the Cochrane Library. Eight studies were identified (six case-control, one cohort, and one cross-sectional). We found that dietary intake of vitamin E protects against PD. This protective influence was seen with both moderate intake (relative risk 0.81, 95% CI 0.67-0.98) and high intake (0.78, 0.57-1.06) of vitamin E, although the possible benefit associated with high intake of vitamin E was not significant. The studies did not suggest any protective effects associated with vitamin C or beta carotene. We conclude that dietary vitamin E may have a neuroprotective effect attenuating the risk of PD. These results require confirmation in randomised controlled trials.

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↗
PubMed2001

Hyperlipidemia and reproductive failure in captive-reared alligators: vitamin E, vitamin A, plasma lipids, fatty acids, and steroid hormones.

Blood samples were collected from 26 captive-reared alligators (25 females; one male) and 12 (seven females and five males) wild "nuisance" alligators collected by wildlife personnel in south Louisiana in May 1995. The captive alligators, hatched from artificially incubated eggs in 1972-1973, had received vitamin E supplements during the 3 weeks before the blood sample was collected. Each sample was analyzed for vitamin E (alpha-tocopherol), vitamin A (retinol), total lipid, triacylglycerol, phospholipid, cholesterol, cholesteryl ester, free fatty acids, steroid hormones and a standard clinical blood panel. The fatty acid composition of the plasma lipid fraction was also analyzed. Results indicated that 18 of the captive females and three of the seven wild females were undergoing vitellogenesis, i.e. had elevated plasma estradiol and elevated plasma calcium. Vitellogenic females had higher vitamin E than non-vitellogenic females (77.4 microg/ml vs. 28.6 microg/ml in captive females; 24.0 microg/ml vs. 21 microg/ml in wild females). Plasma retinol was similar in all groups, ranging from 0.5 to 1.4 microg/ml and close to values reported in birds. All lipid fractions, with the exception of cholesteryl ester, were higher in captive alligators than in wild alligators. There were also significant differences in the fatty acid composition of wild and captive alligators. Plasma eicosapentaenoic and docasahexaenoic acid were higher in wild than in captive alligators, whereas linoleic was higher in captive than in wild.

Alligators and Crocodiles↗
PubMed1998

Inhibition of oxidative DNA damage, 8-OHdG, and carbonyl contents in smokers treated with antioxidants (vitamin E, vitamin C, beta-carotene and red ginseng).

The chemopreventive effects of antioxidants (vitamin E, beta-carotene, vitamin C and red ginseng) on oxidative DNA and protein (globin) damages were comparatively investigated in the peripheral blood of smokers (> or = 20 cigarettes/day). Smokers showed a lower baseline level of plasma micronutrients (vitamin C and beta-carotene) (P < 0.01) and higher baseline level of oxidative DNA or protein damage than non-smokers (N = 5; P < 0.05). During daily supplementation of antioxidants (200 IU vitamin of E, 9 mg of beta-carotene, 500 mg of vitamin C, or 1.8 g of red ginseng) for 4 weeks, smokers plasma antioxidant concentrations increased linearly, while their mean levels of 8-hydroxydeoxyguanosine (8-OHdG) and carbonyl contents decreased compared with those in smokers supplemented with a placebo (P < 0.05). Levels of urinary and plasma cotinine remained steady in smokers regardless of supplementation with antioxidants. 8-OHdG and carbonyl content decreased in a time-dependent manner (as the total intake dose increased) after supplementation with vitamin E (8-OHdG, 33.8%; carbonyl content, 43.6%) or red ginseng (8-OHdG, 31.7%; carbonyl content, 21.3%). These preliminary data suggest that supplementation with antioxidants might protect smokers from oxidative damages and could reduce cancer risk or other diseases caused by free radicals associated with smoking.

8-Hydroxy-2'-Deoxyguanosine↗
PubMed1993

Glycosylated hemoglobin concentrations and vitamin E, vitamin C, and beta-carotene intake in diabetic and nondiabetic older adults.

Studies indicate that large doses of all-rac-alpha-tocopherol in people with diabetes or ascorbic acid in nondiabetic subjects reduces protein glycosylation. The mechanisms by which these nutrients influence glycosylation are poorly understood but may be related to their ability to function as antioxidants. We examined the relationship between glycosylated hemoglobin (GHb) and intake of vitamins E and C and beta-carotene in a population-based sample of middle-aged and older adults participating in the Beaver Dam Eye Study. In people with diabetes, no significant associations were observed between GHb and intake of vitamins E and C and beta-carotene. In people without diabetes, energy-adjusted vitamin C intake was negatively associated with GHb after age and sex were controlled for (dietary, P = 0.02; total, P = 0.04). No significant relationships between GHb and intake of vitamin E and beta-carotene were observed.

Adult↗
PubMed1995

Serum beta-carotene, vitamin E, vitamin C and malondialdehyde levels in several types of cancer.

We measured the levels of serum carotenoids (beta-carotene), total tocopherol (vitamin E), ascorbic acid and malondialdehyde (MDA) in newly diagnosed cancer cases. Levels of the antioxidants and MDA in serum samples from 208 subjects with cancer affecting different sites (59 breast, 38 head and neck, 46 genitourinary, 12 lung, 20 gastrointestinal and 33 other sites) were compared with levels in 156 controls. Cases and controls were compared with respect to a number of potentially confounding factors: age, sex, smoking status, Quetelet index (kg/m2), diet and alcohol intake. Mean (+/- SD) levels of beta-carotene, vitamin E and vitamin C were significantly lower among the cases than the controls (49.35 +/- 36.55 micrograms/l, 0.60 +/- 0.14 mg/dl, 0.40 +/- 0.27 mg/dl and 75.31 +/- 28.59 mg/dl, 0.98 +/- 0.13 mg/dl, 0.88 +/- 0.47 mg/dl, respectively) (P < 0.05). On the other hand, mean levels of MDA were significantly higher among the cases than the controls (6.79 +/- 1.22 nmol/ml and 3.52 +/- 0.97 nmol/ml, respectively) (P < 0.05). The results obtained suggest that measurement of serum antioxidants and MDA levels may provide further useful information when evaluating cancer patients.

Adult↗
PubMed2002

Diet supplementation with vitamin E, vitamin C and beta-carotene cocktail enhances basal neutrophil antioxidant enzymes in athletes.

Exercise increases oxygen consumption and causes a disturbance of intracellular pro-oxidant-antioxidant homeostasis. Few data are available as to the cumulative effects of exercise on the antioxidant defenses of the neutrophil. We studied the effects of 90 days' supplementation with placebo or an antioxidant cocktail of vitamin E (500 mg/day) and beta-carotene (30 mg/day) and the last 15 days also with vitamin C (1 g/day) on sportsmen's basal neutrophil antioxidant defenses. We analyzed the activities of catalase, glutathione peroxidase, glutathione reductase and the activities and levels of superoxide dismutase, glutathione and glutathione disulfide in neutrophils purified from antecubital vein blood of sportsmen before and after diet supplementation. Plasma vitamin E, beta-carotene and vitamin C concentrations in the antioxidant-supplemented group were approximately 1.6, 10, and 1.2 times higher respectively than those of the placebo group. The antioxidant-supplemented group presented a significantly higher glutathione versus glutathione disulfide ratio in neutrophils (about 20%) than the placebo one. Antioxidant supplementation enhances the antioxidant enzyme activity of superoxide dismutase and catalase in neutrophils.

Adult↗
PubMed1987

Routine clinical determination of carotene, vitamin E, vitamin A, 25-hydroxy vitamin D3 and trans-vitamin K1 in human serum by straight phase HPLC.

A universal extraction procedure is described for fat-soluble vitamins in human serum. Methods are presented for routine quantitative analysis by isocratic straight phase HPLC with UV-detection of (alpha + beta)-carotene, vitamin E (alpha-tocopherol) and vitamin A (all-trans-retinol) in one single run, and of vitamin K1 (trans-phylloquinone) and 25-hydroxy vitamin D3 after sample clean-up using disposable reversed-phase cartridges. The limits of detection, precisions and selectivities of the developed assays are shown to be satisfactory after more than three years' experience. The routine clinical determination of fat-soluble vitamins can be performed in less than 5 mL of serum. Analyses of external quality control and randomly taken outpatient samples are shown to be of great value in assessing laboratory performance.

Calcifediol↗
PubMed1985

Vitamin E, vitamin A and essential fatty acid status of patients hospitalized for anorexia nervosa.

A group of 17 patients hospitalized for anorexia nervosa was assessed for nutritional status with respect to the essential fatty acids and vitamins E and A. Plasma aliquots available from blood drawn upon hospital admission were frozen and later extracted for total lipids. The total lipids were then fractionated by thin layer chromatography to isolate the phospholipids (PL). The fatty acid profile of both total plasma and PLs was determined by gas chromatography. High pressure liquid chromatography was used to quantitate the tocopherol isomers and retinol (vitamins E and A, respectively). The anorexic patients showed below normal weight-for-height, decreased percent body fat, and a high incidence of secondary amenorrhea. Of the four tocopherol isomers measured, only the beta + gamma fraction was significantly lower than the normal value (0.16 +/- .06 mg/dl vs 0.25 +/- 0.51 mg/dl, p less than .001). The essential fatty acids, linoleate and linolenate, were lower in the PL fraction of the anorexic group (linoleate, 19.35 +/- 5.65 vs 24.96 +/- 2.24, p less than .01); linolenate, none detected vs 0.16 +/- 0.13, p less than .05). Other indicators of essential fatty acid status differed from the normal group in the direction of deficiency (total omega 6, 31.44 +/- 7.41 vs 37.42 +/- 3.40, p less than .05; 20:4 omega 6/18:2 omega 6, 0.49 +/- 0.14 vs 40 +/- 0.02, mean +/- standard deviation, p less than .01). Eicosatrienoic acid, however, was not detected in either group.(ABSTRACT TRUNCATED AT 250 WORDS)

Adipose Tissue↗
PubMedDate not supplied

Influence of cigarette smoking on vitamin E, vitamin A, beta-carotene and lycopene concentrations in human pre-ovulatory follicular fluid.

Increasing evidence suggests that fat soluble vitamins and micronutrients have the potential for local modulation of follicular development. Cigarette smoking has been associated with accelerated follicular depletion and derangement of reproductive functions. The present study was initiated to investigate the impact of cigarette smoking on follicular and plasma concentrations of vitamin A, vitamin E, lycopene and beta-carotene. Samples were collected from 17 smokers and 43 non-smoking women undergoing assisted reproduction techniques. Assays were carried out by a reverse-phase high-pressure liquid chromatography (HPLC) method. Smokers had significantly (P < 0.05) lower levels of follicular fluid beta-carotene in comparison to non-smokers (0.02 +/- 0.02 vs. 0.09 +/- 0.02, respectively). No other significant influences on follicular and plasma concentrations were noted. Smokers showed a significantly (P < 0.05) lower fertilization rate in comparison to non-smokers, (55.9 % vs. 71.5 % , respectively). It is postulated that follicular depletion of the antioxidant beta-carotene occurs in response to oxidative stress imposed by cigarette smoke.

Adult↗
PubMed1998

Enhancement of nitroxide-reducing activity in rats after chronic administration of vitamin E, vitamin C, and idebenone examined by an in vivo electron spin resonance technique.

Rats were given vitamin E (Vit-E), idebenone (ID), or vitamin C (Vit-C) in their food for 2 or 4 weeks. After feeding, the ability of rats to reduce 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl (Tempol) in terms of the half-life of Tempol was examined as a specific marker. Tempol was repeatedly injected intravenously, and its half-life was serially evaluated by an in vivo electron spin resonance (ESR) technique. The radical-reducing ability in rats was enhanced differently by Vit-E, ID, and Vit-C, i.e., slow onset of the ability after Vit-E and ID (lipid-soluble antioxidants) and fast onset after Vit-C (a water-soluble antioxidant).

Animals↗
PubMed2005

Effects of triple antioxidant combination (vitamin E, vitamin C and alpha-lipoic acid) with insulin on lipid and cholesterol levels and fatty acid composition of brain tissue in experimental diabetic and non-diabetic rats.

The aim of this research was to examine the effects of a triple antioxidant combination (vitamins E (VE) and C (VC) plus alpha-lipoic acid (LA)) on the total lipid and cholesterol levels and the fatty acid composition of brain tissues in experimental diabetic and non-diabetic rats. VE and LA were injected intraperitoneally (50 mg/kg) four times per week and VC was provided as a supplement dissolved in the drinking water (50 mg/kg). In addition, rats in the diabetes 1 and D+VELAVC groups were given daily by subcutaneous insulin injections (8 IU/kg), but no insulin was given to rats in the diabetes 2 group. The results indicate that the brain lipid levels in the D+VELAVC, diabetes 1 and diabetes 2 groups were higher than in the control group (P<0.01). Total lipid was also higher in the non-diabetic rats treated with LA and VC. Total cholesterol was higher in the diabetes 1 and diabetes 2 groups (P<0.05) than in controls. Cholesterol levels were similar in the D+VELAVC and LA groups but lower in the VC, VE and VELAVC groups of non-diabetic rats (P<0.05 and P<0.01). In respect of fatty acid composition, palmitic acid levels were lower in the diabetes 2 and non-diabetic VE groups than the control group (P<0.05), but higher in the non-diabetic LA group (P<0.05). Oleic acid (18:1 n-9) levels were lower in the diabetic and non-diabetic groups than the control group (P<0.01), but higher in the non-diabetic LA group. Arachidonic acid (20:4 n-6) levels were similar in the diabetes 1, D+VELAVC and control groups (P>0.05) but higher in the non-diabetic VE, VC, LA and VEVCLA groups (P<0.05) and lower in the diabetes 2 group (P<0.05). Docosahexaenoic acid (22:6 n-3) was elevated in the diabetes 2 and VEVCLA groups (P<0.01, P<0.05). In conclusion, the current study confirmed that treatment with a triple combination of VE, VC and LA protects the arachidonic acid level in the brains of diabetic and non-diabetic rats.

Animals↗
PubMed1994

The relationship between micronuclei in human lymphocytes and plasma levels of vitamin C, vitamin E, vitamin B12 and folic acid.

The cytokinesis-block micronucleus assay is increasingly being applied to the study of spontaneous or induced genetic damage in human lymphocytes, but little is known about dietary and other lifestyle factors that could influence this index. As part of a larger study investigating the role of dietary factors on baseline genetic damage in human lymphocytes from 152 non-smoking females and 113 non-smoking males evenly distributed between the ages of 20 and 87 years, we have measured (a) the micronucleus (MN) frequency and (b) the plasma level of the anti-oxidant vitamins C and E and the B vitamins folic acid and B12. Multiple regression analysis indicated that age (beta value = 0.598, P < 0.0001) was the most important factor influencing the variance of micronucleus frequency in females, while micronutrient levels had no apparent significant effects on genetic damage. In males age was also the predominant factor (beta value = 0.505, P < 0.0001) influencing genetic damage, but vitamin-C level also contributed positively and significantly to the observed MN frequency (beta value = 0.220, P < 0.0228). To avoid the potential confounding effect of collinearity between variables we also performed separate simple regression analysis for each plasma micronutrient in relation to age-adjusted micronucleus frequency; the results from this analysis again showed a significant and positive effect of plasma vitamin C on age-adjusted micronucleus frequency in males only (beta value = 0.188, P = 0.0503), while no effect was observed for the other micronutrients in both sexes. In view of the predominant age effect, we also focused on the data obtained in the youngest age groups of both sexes. In view of the predominant age effect, we also focused on the data obtained in the youngest age groups of both sexes (i.e. 20-30 years olds) and found (a) that the MN frequency in young males is significantly and positively correlated with plasma vitamin C levels (r = 0.823, P < 0.001) but negatively correlated with plasma vitamin B12 status (r = -0.799, P < 0.001) and (b) in females the only significant correlation was an inverse relationship between MN frequency and the combined folate and vitamin B12 plasma levels (r = -0.4632, P < 0.030).(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗