Plasma Alpha-tocopherol Levels Research Articles

Effect of combined treatment with Methotrexate and Non-steroidal anti-inflammatory drugs on plasma alpha-tocopherol level and Rheumatoid factor among Rheumatoid Arthritis patients

Background: Oxidative stress might play a significant role in the pathogenesis of Rheumatoid Arthritis. Traditional therapies of Rheumatoid Arthritis are governed by different NSAIDs which improve symptoms of Rheumatoid Arthritis. But addition of Methotrexate (MTX) to Non-steroidal anti-inflammatory drugs (NSAIDs) has been found to be extra beneficial by halting the disease process. Objectives: To evaluate the status of anti-oxidant alpha-tocopherol and rheumatoid factor before and after treatment with MTX and NSAIDs for two months in Rheumatoid Arthritis patients. Methods: This quasi-experimental study was carried out in the Department of Pharmacology and Therapeutics of Rajshahi Medical College, Rajshahi between the periods of January 2011 to December 2011. Total ten clinically diagnosed Rheumatoid Arthritis patients were enrolled in the study. Purposive sampling technique was used to select each study subject from medicine wards of Rajshahi Medical College Hospital. Alpha-tocopherol, an anti-oxidant in plasma was measured as marker of anti-oxidant defense. The patients were then treated with oral MTX at a dose of 10 mg weekly and Indomethacin 150 mg in three divided doses daily for 2 months. After 2 months of continuous aforementioned treatment, alpha-tocopherol levels were estimated again. Moreover qualitative assessment of rheumatoid factor was done. For statistical analysis, paired t-test was done. Results: After two months of treatment with Methotrexate and Indomethacin, plasma alpha-tocopherol levels were significantly higher (P<0.05) in Rheumatoid Arthritis patients. However no significant change was observed in qualitative assessment of rheumatoid factors. Conclusion: From the findings of this study, it can be concluded that the endogenous alpha-tocopherol level increases even without any supplementation of alpha-tocopherol by combined treatment with MTX and Indomethacin in Rheumatoid Arthritis patients and thereby reduces oxidative stress. So alpha-tocopherol level is a better marker for early assessment of prognosis of Rheumatoid arthritis than Rheumatoid factor test. Mediscope 2021;8(2): 80-86

Plasma Metabolomic Profiling Associates Bicuspid Aortic Valve Disease and Ascending Aortic Dilation with a Decrease in Antioxidant Capacity.

Background: The bicuspid aortic valve (BAV) is the most common cardiac congenital disease and is associated with an increased risk of developing ascending aorta dilation; which can have fatal consequences. Currently; no established risk biomarkers exist to facilitate the diagnosis and prognosis of BAV. Methods: Using an untargeted metabolomic approach; we identified the levels of metabolites in plasma samples and compared them depending on the bicuspid or tricuspid morphology of the aortic valve. Including those patients with ascending aortic dilation and/or aortic stenosis (n = 212), we analyzed the role possibly played by alpha-Tocopherol in BAV disease; considering its association with the pathophysiological characteristics of BAV and biomarkers related to inflammation, oxidative stress and endothelial damage, as well as characteristics related to alpha-Tocopherol functionality and metabolism. Results: We found that BAV patients; especially those with ascending aortic dilation; presented lower antioxidant capacity; as determined by decreased plasma levels of alpha-Tocopherol; paraoxonase 1 and high-density lipoprotein (HDL), as well as increased levels of C-reactive protein (CRP; a biomarker of inflammation) and endothelial microparticles (EMPs; an endothelial damage biomarker). By applying random forest analyses; we evaluated the significant screening capacity of alpha-Tocopherol; CRP and EMPs to classify patients depending on the morphology of the aortic valve. Discussion: Our findings support the role of decreased antioxidant capacity; increased inflammation and endothelial damage in the pathogenesis of BAV and the progression of aortic dilation. Moreover; determining the plasma levels of alpha-Tocopherol; CRP and EMPs could improve BAV diagnosis in large populations.

Postoperative Administration of Alpha-tocopherol Enhances Osseointegration of Stainless Steel Implants: An In Vivo Rat Model.

Alpha-tocopherol, a well-known antioxidative agent, may have a positive effect on bone formation during the remodeling phase of secondary fracture healing. Fracture healing and osseointegration of implants share common biological pathways; hence, alpha-tocopherol may enhance implant osseointegration. This experimental study in rats assessed the ability of alpha-tocopherol to enhance osseointegration of orthopaedic implants as determined by (1) pull-out strength and removal torque and (2) a histomorphological assessment of bone formation. In addition, we asked, (3) is there a correlation between the administration of alpha-tocopherol and a reduction in postoperative oxidative stress (as determined by malondialdehyde, protein carbonyls, reduced and oxidized glutathione and their ratio, catalase activity and total antioxidant capacity) that develops after implantation of an orthopaedic implant? This blinded study was performed in study and control groups, each consisting of 15 young adult male Wistar rats. On Day 0, a custom-designed stainless-steel screw was implanted in the proximal metaphysis of both tibias of all rats. On Day 1, animals were randomized to receive either alpha-tocopherol (40 mg/kg once per day intraperitoneally) or saline (controls). Animals were treated according to identical perioperative and postoperative protocols and were euthanized on Day 29. All animals completed the study and all tibias were suitable for evaluation. Implant pullout strength was assessed in the right tibias, and removal torque and histomorphometric evaluations (that is, volume of newly formed bone surrounding the implant in mm, percentage of newly formed bone, percentage of bone marrow surrounding the implant per optical field, thickness of newly formed bone in μm, percentage of mineralized bone in newly formed bone, volume of mature newly formed bone surrounding the implant in mm and percentage of mineralized newly formed bone per tissue area) were performed in the left tibias. The plasma levels of alpha-tocopherol, malondialdehyde, protein carbonyls, glutathione, glutathione disulfide, catalase, and the total antioxidant capacity were evaluated, and the ratio of glutathione to oxidized glutathione was calculated. All parameters were different between the alpha-tocopherol-treated and control rats, favoring those in the alpha-tocopherol group. The pullout strength for the alpha-tocopherol group (mean ± SD) was 124.9 ± 20.7 newtons (N) versus 88.1 ± 12.7 N in the control group (mean difference -36.7 [95% CI -49.6 to -23.9]; p < 0.001). The torque median value was 7 (range 5.4 to 8.3) versus 5.2 (range 3.6 to 6 ) N/cm (p < 0.001). The newly formed bone volume was 29.8 ± 5.7 X 10 versus 25.2 ± 7.8 X 10 mm (mean difference -4.6 [95% CI -8.3 to -0.8]; p = 0.018), the percentage of mineralized bone in newly formed bone was 74.6% ± 8.7% versus 62.1% ± 9.8% (mean difference -12.5 [95% CI -20.2 to -4.8]; p = 0.003), the percentage of mineralized newly formed bone per tissue area was 40.3 ± 8.6% versus 34.8 ± 9% (mean difference -5.5 [95% CI -10.4 to -0.6]; p = 0.028), the glutathione level was 2 ± 0.4 versus 1.3 ± 0.3 μmol/g of hemoglobin (mean difference -0.6 [95% CI -0.9 to -0.4]; p < 0.001), the median glutathione/oxidized glutathione ratio was 438.8 (range 298 to 553) versus 340.1 (range 212 to 454; p = 0.002), the catalase activity was 155.6 ± 44.6 versus 87.3 ± 25.2 U/mg Hb (mean difference -68.3 [95% CI -95.4 to -41.2]; p < 0.001), the malondialdehyde level was 0.07 ± 0.02 versus 0.14 ± 0.03 μmol/g protein (mean difference 0.07 [95% CI 0.05 to 0.09]; p < 0.001), the protein carbonyl level was 0.16 ± 0.04 versus 0.27 ± 0.08 nmol/mg of protein (mean difference -0.1 [95% CI 0.05 to 0.15]; p = 0.002), the alpha-tocopherol level was 3.9 ± 4.1 versus 0.9 ± 0.2 mg/dL (mean difference -3 [95% CI -5.2 to -0.7]; p = 0.011), and the total antioxidant capacity was 15.9 ± 3.2 versus 13.7 ± 1.7 nmol 2,2-diphenyl-1-picrylhydrazyl radical/g of protein (mean difference -2.1 [95% CI -4.1 to -0.18]; p = 0.008). These results using an in vivo rat model support that postoperatively administered alpha-tocopherol can enhance the osseointegration of an orthopaedic implant, although a cause and effect relationship between the administration of alpha-tocopherol and a reduction in postoperative stress cannot be securely established. These findings suggest that postoperative administration of alpha-tocopherol is a promising approach to enhance osseointegration of orthopaedic implants in patients. Further studies with different animal models and/or different implants and those evaluating the alpha-tocopherol dose response are needed before performing clinical trials that will examine whether these promising, preliminary results can be extrapolated to the clinical setting as well.

Daily consumption of a dark-roast coffee for eight weeks improved plasma oxidized LDL and alpha-tocopherol status: A randomized, controlled human intervention study

Abstract Scope Coffee consumption is widely recognized to improve the antioxidant status. We hypothesized a dark-roast coffee to reduce plasma oxidized LDL (oxLDL) and to improve alpha-tocopherol concentrations. Methods and results After a 4 week, coffee-free run-in period, 86 healthy, randomized volunteers completed either a control (CTRL) or coffee (COFF) intervention in which either 750 mL water (CTRL) or coffee (COFF) were consumed daily for 8 weeks. Blood samples were taken at the begin and after the intervention. Mean changes in oxidized LDL concentrations after coffee consumption (−0.47 ± 15.4 U/L) differed from those of the CTRL-G (5.69 ± 18.8 U/L, p Conclusion Improved plasma alpha-tocopherol levels and reduced levels of plasma oxLDL after 8 week consumption of a dark-roast coffee rich in N-methylpyridinium are hypothesized to be caused by coffee-induced lipolysis, resulting in increased alpha-tocopherol mobilisation.

Delineation of the Individual Effects of Vitamin E Isoforms on Early Life Incident Wheezing

To test the hypothesis that maternal plasma alpha-tocopherol levels are associated with protection from childhood wheeze and that this protection is modified by gamma-tocopherol. We conducted a prospective nested study in the Infant Susceptibility to Pulmonary Infections and Asthma Following Respiratory Syncytial Virus Exposure birth cohort of 652 children with postpartum maternal plasma vitamin E isoforms used as a surrogate for pregnancy concentrations. Our outcomes were wheezing and recurrent wheezing over a 2-year period, ascertained using validated questionnaires. We assessed the association of alpha- and gamma-tocopherol with wheezing outcomes using multivariable adjusted logistic regression, and tested for interaction between the isoforms with respect to the risk for wheezing outcomes. Children with wheezing (n = 547, n = 167; 31%) and recurrent wheezing (n = 545, n = 55; 10.1%) over a 2-year period were born to mothers with significantly lower postpartum maternal plasma concentrations of alpha-tocopherol, P = .016 and P = .007, respectively. In analyses of IQR increases, alpha-tocopherol was associated with decreased risk of wheezing (aOR 0.70 [95% CI 0.53,0.92]) and recurrent wheezing (aOR 0.63 [95% CI 0.42,0.95]). For gamma-tocopherol, the aOR for wheezing was 0.79 (95% CI 0.56-1.10) and the aOR for recurrent wheezing was 0.56 (95% CI 0.33-0.94, with nonmonotonic association). The association of alpha-tocopherol with wheezing was modified by gamma-tocopherol (P interaction = .05). Increases in postpartum maternal plasma alpha-tocopherol isoform concentrations were associated with decreased likelihood of wheezing over a 2-year period. Gamma-tocopherol modified this association.

Self-reported adherence and biomarker levels of CoQ10 and alpha-tocopherol.

PurposeWomen with breast cancer were randomized to receive coenzyme Q10 (CoQ10) plus Vitamin E or placebo in a clinical trial. The objective of this evaluation is to examine the association between participant self-reported adherence to the study supplements and changes in plasma biomarker levels.Patients and methodsCorrelation coefficients quantified the association between changes in alpha-tocopherol and CoQ10 levels and the association between self-reported adherence and changes in biomarkers. Participants were categorized by self-reported adherence; Kruskal– Wallis tests compared changes in alpha-tocopherol and CoQ10 levels between self-reported adherence groups.ResultsWomen (N=155) provided baseline and post-treatment biomarkers; 147 completed at least one diary. While changes in alpha-tocopherol and CoQ10 levels were moderately correlated, correlations ranged from 0.40 to 0.48, association between self-reported adherence and plasma alpha-tocopherol or CoQ10 levels was weak; correlations ranged from 0.10 to 0.29 at weeks 8, 16, and 24. Some participants with high self-reported adherence actually had decreases in their biomarker levels.ConclusionThese findings support that self-reported adherence is likely to be overestimated. Biological and other measures of adherence that can better identify true adherence to study pills provided in clinical trials are greatly needed as they may assist in improving the interpretation of findings of future clinical trials.

Whole-food phytochemicals antioxidative potential in alloxan-diabetic rats.

The importance of whole-food antioxidants in terms of promoting antioxidant recycling in the body in complex human diseases is not fully understood. We aim to discuss the benefits of whole-food antioxidants in ameliorating the diabetic complications in vivo and to address the effect of germination versus heat processing or drying on the potential therapeutic effect of whole grains and legumes. We studied the antioxidant status of alloxan-diabetic (AD) male Spargue Dawley rats, injected intraperitoneally with alloxan dose of 150 mg/kg body weight, and fed on experimental diets based on the flour of soybean, broadbean and whole-wheat for five weeks. Diabetes-induced oxidative stress in liver was manifested by significant increase in hepatic malondialdehyde (MDA), erythrocytes superoxide dismutase (eSOD) and plasma alpha-tocopherol (α-T) levels, reduction in hepatic glutathione (GSH) levels and catalase (CAT) activity. Consumption of soybean and whole-wheat both had beneficial effects on the oxidative status of AD rats more than broadbean. Feeding dried wheat was effective in improving MDA, GSH and α-T levels. Soybeans and wheat lowered triacylglycerols (TAGs) and tended to lower total cholesterol. Germination enhanced the effect of soybeans on TAGs and in the case of soy and wheat enhanced the effect on total cholesterol. Whole foods containing naturally occurring phytochemicals and antioxidant vitamins such as legumes and whole grains are recommended, alongside medication, for controlling hyperglycaemia, blood lipids and oxidative status in diabetes.

Plasma alpha-tochopherol determined by HPLC in dogs at different stages of chronic kidney disease: a retrospective study.

The aim of the present study was to investigate retrospectively the plasma concentration of alpha-tocopherol in dogs with naturally acquired chronic kidney disease (CKD), at different stages of severity. Forty dogs (CKD group) with different stages of CKD (IRIS 1 n=12, IRIS 2 n=8, IRIS 3 n=11, IRIS 4 n=9) and 20 clinically healthy dogs were considered. Plasma alpha-tocopherol was assessed in both groups through high performance liquid chromatography (HPLC). Dogs of CKD group showed significantly lower (p=0.0002) levels of plasma alpha-tocopherol compared with clinically healthy dogs. A significant difference (p<0.04) in the number of patients with plasma alpha-tocopherol > or ≤ 21.5 ppm was found in CKD patients at different stages of severity. No significant correlation between plasma levels of alpha-tocopherol and plasma creatinine was found. In the present study, dogs affected by spontaneous CKD showed significantly lower plasma concentrations of alpha-tocopherol compared with clinically healthy dogs. Plasma alpha-tocopherol deficiency seems to be more severe in IRIS stage 1 and 4, compared with IRIS stage 2 and 3. The finding of marked alpha-tocopherol deficiency in patients in IRIS stage 1 should encourage further studies on the early use of prescription renal diet and antioxidant in this group of patients.

In Vitro Assessment of Tobacco Smoke Toxicity at the BBB: Do Antioxidant Supplements Have a Protective Role?

BackgroundTobacco smoke (TS) contains highly reactive oxygen species (such as hydrogen peroxide, peroxynitrite, etc), which cause oxidative damage in vascular tissue and may exacerbate inflammatory events leading to the blood-brain barrier damage (BBBD) which accompanies the development of a variety of neurological disorders. Smokers often have elevated leukocyte counts (primarily neutrophils and monocytes), and significant decreases in plasma alpha-tocopherol (vitamin E) and ascorbic acid (vitamin C) levels due to increased anti-oxidative mobilization in response to oxidative stress evoked by TS. For this purpose, using static culture systems and a well-established dynamic in vitro BBB model (DIV-BBB) we tested the hypothesis that antioxidant vitamin supplementation (E and/or C) can protect the BBB during exposure to whole soluble TS.ResultsTS exacerbates inflammatory events and leads to endothelial overexpression of vascular adhesion molecules (VCAM-1, P-selectin and E-selectin), release of pro-inflammatory cytokines (TNF-α and IL-6) and nitric oxide (NO), release and activation of matrix metalloproteinases (MMP-2 and MMP-9), monocytic maturation into macrophages, and adhesion to the vascular endothelium. Furthermore, TS altered the normal glucose metabolic behaviour of in vitro BBB capillaries and caused a period of transient anaerobic respiration to meet the cellular bioenergetic demand. Pre-treatment with antioxidant vitamins (C and/or E) effectively reduced the pro-inflammatory activity associated with TS, protecting the viability and functions of the BBB.ConclusionOur results have shown that loss of endothelial viability as well as BBB function and integrity caused by TS exposure can be prevented or at least reduced by normal physiologic concentrations of antioxidant vitamins in vitro.

Down syndrome and dementia: A randomized, controlled trial of antioxidant supplementation

Individuals with Down syndrome over age 40 years are at risk for developing dementia of the Alzheimer type and have evidence for chronic oxidative stress. There is a paucity of treatment trials for dementia in Down syndrome in comparison to Alzheimer disease in the general (non-Down syndrome) population. This 2-year randomized, double-blind, placebo-controlled trial assessed whether daily oral antioxidant supplementation (900 IU of alpha-tocopherol, 200 mg of ascorbic acid and 600 mg of alpha-lipoic acid) was effective, safe and tolerable for 53 individuals with Down syndrome and dementia. The outcome measures comprised a battery of neuropsychological assessments administered at baseline and every 6 months. Compared to the placebo group, those individuals receiving the antioxidant supplement showed neither an improvement in cognitive functioning nor a stabilization of cognitive decline. Mean plasma levels of alpha-tocopherol increased ~2-fold in the treatment group and were consistently higher than the placebo group over the treatment period. Pill counts indicated good compliance with the regimen. No serious adverse events attributed to the treatment were noted. We conclude that antioxidant supplementation is safe, though ineffective as a treatment for dementia in individuals with Down syndrome and Alzheimer type dementia. Our findings are similar to studies of antioxidant supplementation in Alzheimer disease in the general population. The feasibility of carrying out a clinical trial for dementia in Down syndrome is demonstrated.

Protective effects of plasma alpha-tocopherols on the risk of inorganic arsenic-related urothelial carcinoma

Arsenic plays an important role in producing oxidative stress in cultured cells. To investigate the interaction between high oxidative stress and low arsenic methylation capacity on arsenic carcinogenesis, a case–control study was conducted to evaluate the relationship among the indices of oxidative stress, such as urinary 8-hydroxydeoxyquanine (8-OHdG), as well as plasma micronutrients and urinary arsenic profiles on urothelial carcinoma (UC) risk. Urinary 8-OHdG was measured using high-sensitivity enzyme-linked immunosorbent assay kits. The urinary arsenic species were analyzed using high-performance liquid chromatography and hydride generator-atomic absorption spectrometry. Plasma micronutrient levels were analyzed using reversed-phase high-performance liquid chromatography. The present study showed a significant protective effect of plasma alpha-tocopherol on UC risk. Plasma alpha-tocopherol levels were significantly inversely related to urinary total arsenic concentrations and inorganic arsenic percentage (InAs%), and significantly positively related to dimethylarsinic acid percentage (DMA%). There were no correlations between plasma micronutrients and urinary 8-OHdG. Study participants with lower alpha-tocopherol and higher urinary total arsenic, higher InAs%, higher MMA%, and lower DMA% had a higher UC risk than those with higher alpha-tocopherol and lower urinary total arsenic, lower InAs%, lower MMA%, and higher DMA%. These results suggest that plasma alpha-tocopherol might modify the risk of inorganic arsenic-related UC.

Vitamin E in human serum and colostrum under fasting and postprandial conditions

To evaluate alpha-tocopherol concentrations in maternal serum and colostrum under fasting and postprandial conditions. Thirty healthy childbearing women were recruited in a public maternity hospital, and samples of blood, fasting colostrum, and postprandial colostrum were collected from them up to 12 hours after delivery. The serum alpha-tocopherol concentration was 1,939.8+/-766.0 microg/dL. Alpha-tocopherol levels in fasting colostrum (1,603.4+/-911.0 microg/dL) and in postprandial colostrum (1,515.0+/-890.9 microg/dL) did not demonstrate a statistically significant difference (p > 0.05). There was correlation between alpha-tocopherol levels in fasting and postprandial colostrum (p < 0.05), but not between serum and colostrum. The lack of correlation between alpha-tocopherol levels in plasma and in colostrum, and the correlation between alpha-tocopherol concentrations in fasting and postprandial colostrum support the existence of a mechanism that controls the transfer of this nutrient, regardless of dietary intake.

Vitamina E no soro e colostro humanos em condições de jejum e pós-prandial

OBJETIVO: Avaliar a concentração de alfa-tocoferol no soro e colostro maternos, seja em condições de jejum ou pós-prandial. MÉTODOS: Trinta parturientes saudáveis atendidas em uma maternidade pública foram recrutadas para o estudo, e amostras de sangue, colostro em jejum e colostro pós-prandial foram coletadas até 12 horas pós-parto. RESULTADOS: A concentração sérica de alfa-tocoferol foi de 1.939,8±766,0 μg/dL. O alfa-tocoferol no colostro em jejum, 1.603,4±911,0 μg/dL, e após a refeição, 1.515,0±890,9 μg/dL, não apresentaram diferença significativa (p > 0,05). Houve correlação entre o alfa-tocoferol do colostro na condição de jejum e no pós-prandial (p < 0,05), mas não entre o soro e o colostro. CONCLUSÃO: A falta de correlação entre o alfa-tocoferol no plasma e no colostro e a correlação entre o alfa-tocoferol no colostro em jejum e no pós-prandial reforçam a hipótese de um mecanismo de controle na passagem desse micronutriente, independente do aporte dietético.

Conjugated Linoleic Acid Causes a Marked Increase in Liver α-Tocopherol and Liver α-Tocopherol Transfer Protein in C57BL/6 J Mice

Conjugated linoleic acid (CLA) is a collective term for the positional and geometric isomers of a conjugated diene of linoleic acid (C18:2, n-6). The aims of the present study were to evaluate whether levels of hepatic alpha-tocopherol, alpha-tocopherol transfer protein (alpha-TTP), and antioxidant enzymes in mice were affected by a CLA-supplemented diet. C57BL/6 J mice were divided into the CLA and control groups, which were fed, respectively, a 5 % fat diet with or without 1 g/100 g of CLA (1:1 mixture of cis-9, trans-11 and trans-10, cis-12) for four weeks. alpha-Tocopherol levels in plasma and liver were significantly higher in the CLA group than in the control group. Liver alpha-TTP levels were also significantly increased in the CLA group, the alpha-TTP/beta-actin ratio being 2.5-fold higher than that in control mice (p<0.01). Thiobarbituric acid-reactive substances were significantly decreased in the CLA group (p<0.01). There were no significant differences between the two groups in levels of three antioxidant enzymes (superoxide dismutase, glutathione peroxidase, and catalase). The accumulation of liver alpha-tocopherol seen with the CLA diet can be attributed to the antioxidant potential of CLA and the ability of alpha-TTP induction. The lack of changes in antioxidant enzyme protein levels and the reduced lipid peroxidation in the liver of CLA mice are due to alpha-tocopherol accumulation.

Alpha-tocopherol supplementation decreases electronegative low-density lipoprotein concentration [LDL(-)] in haemodialysis patients

Oxidative stress is a significant contributor to cardiovascular diseases (CVD) in haemodialysis (HD) patients, predisposing to the generation of oxidized low-density lipoprotein (oxLDL) or electronegatively charged LDL subfraction. Antioxidant therapy such as alpha-tocopherol acts as a scavenger of lipid peroxyl radicals attenuating the oxidative stress, which decreases the formation of oxLDL. The present study was designed to investigate the influence of the alpha-tocopherol supplementation on the concentration of electronegative low-density lipoprotein [LDL(-)], a minimally oxidized LDL, which we have previously described to be high in HD patients. Blood samples were collected before and after 120 days of supplementation by alpha-tocopherol (400 UI/day) in 19 stable HD patients (50 +/- 7.8 years; 9 males). The concentrations of LDL(-) in blood plasma [using an anti-LDL- human monoclonal antibody (mAb)] and the anti-LDL(-) IgG auto-antibodies were determined by ELISA. Calculation of body mass index (BMI) and measurements of waist circumference (WC), triceps skin folds (TSF) and arm muscle area (AMA) were performed. The plasma alpha-tocopherol levels increased from 7.9 microM (0.32-18.4) to 14.2 microM (1.22-23.8) after the supplementation (P = 0.02). The mean concentration of LDL(-) was reduced from 570.9 microg/mL (225.6-1241.0) to 169.1 microg/mL (63.6-621.1) (P < 0.001). The anti-LDL(-) IgG auto-antibodies did not change significantly after the supplementation. The alpha-tocopherol supplementation also reduced the total cholesterol and LDL-C levels in these patients, from 176 +/- 42.3 mg/dL to 120 +/- 35.7 mg/dL (P < 0.05) and 115.5 +/- 21.4 mg/dL to 98.5 +/- 23.01 mg/dL (P < 0.001), respectively. The oral administration of alpha-tocopherol in HD patients resulted in a significant decrease in the LDL(-), total cholesterol and LDL-C levels. This effect may favour a reduction in cardiovascular risk in these patients, but a larger study is required to confirm an effect in this clinical setting.

Plasma vitamins E and A and risk of bladder cancer: a case–control analysis

Current results on the association between serum micronutrients and bladder cancer risk have been inconsistent. We assessed plasma vitamin E (alpha-tocopherol, and gamma-tocopherol), vitamin A (retinol), and bladder cancer risk using data collected from a case-control study. Epidemiologic data were collected via in-person interview. Plasma concentrations of alpha-tocopherol, gamma-tocopherol, and retinol were determined by a high-performance liquid chromatography assay. Multivariate logistic regression analyses were used to estimate bladder cancer risk in association with plasma vitamins E and A. 386 bladder cancer patients and 389 age-, gender-, and ethnicity-matched controls were included in the study. The mean plasma alpha-tocopherol and retinol were significantly lower in cases than in controls (alpha-tocopherol: 23.93 microg/ml vs. 27.48 microg/ml, P < 0.001; retinol: 1.41 microg/ml vs. 1.53 microg/ml, P < 0.001). There was a significant reduction in bladder cancer risk associated with increasing plasma alpha-tocopherol level (Adjusted OR: 0.91; 95% CI: 0.85-0.97). In quartile analysis, using subjects with the lowest alpha-tocopherol level as the reference group, the adjusted ORs and 95% CIs for the second, third, and fourth quartiles were 0.75 (0.50-1.14), 0.69 (0.46-1.05), and 0.50 (0.32-0.78), respectively (P for trend = 0.003). Increased retinol level was also associated with reduced risk with OR of 0.57 (95% CI: 0.40-0.81). The ORs and 95% CIs for the second, third, and fourth quartiles were 0.92 (0.61-1.39), 0.66 (0.43-1.01), and 0.62 (0.40-0.95), respectively, with significant dose-response trend (P for trend = 0.01). Finally, there were significant correlations between plasma levels and dietary intakes for the three micronutrients. Our results suggest potential protective effect of alpha-tocopherol and retinol on bladder cancer risk. Future large prospective studies are needed to confirm the findings.

Gamma Tocopherol alone and in Combination with Alpha Tocopherol Decreases Biomarkers of Oxidative Stress and Inflammation in Subjects with Metabolic Syndrome

Metabolic syndrome (MetS) is associated with increased incidence of diabetes and cardiovascular disease (CVD). Prospective clinical trials with alpha tocopherol (AT) have been equivocal. AT supplementation decreases circulating gamma tocopherol (GT), thus, we tested supplementation with GT (800 mg/day), AT ( 800 mg/day), the combination or placebo for 6 weeks on AT and GT concentrations, biomarkers of oxidative stress and inflammation in MetS subjects (n=20/group). Plasma AT and GT levels increased following supplementation with AT alone, GT alone or in combination. AT supplementation significantly decreased GT levels. Urinary alpha and gamma CEHC, metabolites of the respective Ts also increased correspondingly, with the combination resulting in significant increases in both compared to placebo. HsCRP significantly decreased in the combined AT +GT group (p&lt;0.05). There was a significant decrease in TNF with AT alone or in combination with GT. Plasma MDA/HNE and lipid peroxides were significantly decreased with AT, GT alone or in combination (p&lt;0.01). Nitrotyrosine levels were significantly decreased only with GT or GT+AT but not with AT (p&lt;0.01). Thus, the combination of AT and GT supplementation appears to be superior to either alone on biomarkers of oxidative stress and inflammation and needs to be tested in prospective clinical trials to elucidate its utility in CVD prevention.

Supplementation of coenzyme Q10 and α-tocopherol lowers glycated hemoglobin level and lipid peroxidation in pancreas of diabetic rats

The importance of nutritional supplementation in diabetes remains an unresolved issue. The present study was undertaken to examine the effects of alpha-tocopherol and CoQ(10), powerful antioxidants, on metabolic control and on the pancreatic mitochondria of GK rats, a model of type 2 diabetes. We also evaluated the efficacy of these nutrients in preventing the diabetic pancreatic lesions observed in GK rats. Rats were divided into 4 groups, a control group of diabetic GK rats and 3 groups of GK rats administered with alpha-tocopherol and CoQ(10) alone or both in association, during 8 weeks. Fasting blood glucose levels were not significantly different between the groups, nor were blood glucose levels at 2 hours after a glucose load. HbA1c level was significantly reduced in the group supplemented with both antioxidants. Diabetes induced a decrease in coenzyme Q plasma levels that prevailed after treatment with antioxidants. In addition, the plasma alpha-tocopherol levels were higher after treatment with the antioxidants. An increment in some components of the antioxidant defense system was observed in pancreatic mitochondria of treated GK rats. Moreover, the antioxidants tested either alone or in association failed to prevent the pancreatic lesions in this animal model of type 2 diabetes. In conclusion, our results indicate that CoQ(10) and alpha-tocopherol decrease glycated HbA1c and pancreatic lipid peroxidation. These antioxidants increase some components of the antioxidant defense system but do not prevent pancreatic lesions. Thus, we cannot rule out the potential benefit of antioxidant treatments in type 2 diabetes in the prevention of their complications.

Oxidative stress status in liver mitochondria and lymphocyte DNA damage of atherosclerotic rabbits supplemented with water soluble coenzyme Q10

The effects of the administration of water soluble coenzyme Q10 (25 mg/kg per day) over 30 days, after 50 days feeding on a high-fat diet (3% lard + 1.3% cholesterol), were investigated in the plasma and liver mitochondria of rabbits. Results showed that this atherogenic diet enhanced lipid levels both in plasma and liver mitochondria, reduced plasma and mitochondrial concentrations of retinol and coenzyme Q10, led to higher DNA damage in peripheral blood lymphocytes and reactive oxygen species concentration in liver mitochondria. The treatment of animals with coenzyme Q10 reduced (to the healthy group levels) lipid concentration in liver mitochondria with no effect on plasma lipids, increased mitochondrial levels of alpha-tocopherol, restored mitochondrial coenzyme Q10 and improved alpha-tocopherol levels in plasma. Moreover, coenzyme Q10 supplementation reduced mitochondrial reactive oxygen species levels and decreased DNA damage in peripheral blood lymphocytes. The findings suggest that antioxidant therapy with coenzyme Q10 may be used in the treatment of liver pathologies associated to the intake of high-fat, atherogenic, diets.

Gamma-tocopherol supplementation alone and in combination with alpha-tocopherol alters biomarkers of oxidative stress and inflammation in subjects with metabolic syndrome

Metabolic syndrome (MetS) is associated with increased incidence of diabetes and cardiovascular disease (CVD). Prospective clinical trials with alpha-tocopherol (AT) have not yielded positive results. Because AT supplementation decreases circulating gamma-tocopherol (GT), we evaluated supplementation with GT (800 mg/day), AT (800 mg/day), the combination or placebo for 6 weeks alone AT and GT concentrations, biomarkers of oxidative stress, and inflammation in subjects with MetS ( n = 20/group). Plasma AT and GT levels increased following supplementation with AT alone or GT alone or in combination. AT supplementation significantly decreased GT levels. Urinary alpha- and gamma-CEHC, metabolites of the respective Ts, also increased correspondingly, i.e., alpha-CEHC with AT and gamma-CEHC with GT supplementation, compared to placebo. HsCRP levels significantly decreased in the combined AT+GT group. LPS-activated whole blood release of IL-1 and IL-6 did not change. There was a significant decrease in TNF with AT alone or in combination with GT. Plasma MDA/HNE and lipid peroxides were significantly decreased with AT, GT, or in combination. Nitrotyrosine levels were significantly decreased only with GT or GT+AT but not with AT compared to placebo. Thus, the combination of AT and GT supplementation appears to be superior to either supplementation alone on biomarkers of oxidative stress and inflammation and needs to be tested in prospective clinical trials to elucidate its utility in CVD prevention.