Lipid-soluble Antioxidant Vitamin Research Articles

Impact of Heat Stress on the Balance between Oxidative Markers and the Antioxidant Defence System in the Plasma of Mid-Lactating Modicana Dairy Cows.

Animal health is affected during heat stress as a result of impaired immune responses, increased production of reactive oxygen species, and/or a deficiency of antioxidants. This leads to an imbalance between oxidants and antioxidants and results in oxidative stress. Heat stress is usually measured in dairy cattle via the temperature-humidity index (THI). In the present study, we aimed at assessing the influence of incremental THI on the balance between oxidative markers and the antioxidant defence system in the plasma of Modicana cows. Twenty-four multiparous, mid-lactating dairy cows were divided into two groups on the basis of different levels of mean THI reached in the period of the previous week up until the day of blood and milk sampling (April THI1:55, May THI2:68, June THI3:71, July THI4:80). The blood samples were collected to measure reactive oxygen metabolites (ROM) and antioxidant defense markers (ferric reducing ability of plasma (FRAP), paraoxonase (PON), advanced oxidation protein products (AOPP), plasma thiol groups (SHp), as well as lipid-soluble antioxidant pro-vitamin (β-carotene) and vitamins (tocopherol and retinol). Milk characteristics, haematological values, and plasma biochemical metabolites were also evaluated. Results showed a significant increase in ROM (p < 0.05) and a significant decrease in PON (p < 0.05), AOPP (p < 0.05), and β-carotene (p < 0.001). Incremental THI significantly decreased levels of milk fat content, red and white blood cells, plasma glucose, and non-esterified fatty acids, while significantly increasing monocytes and the concentrations of β-hydroxybutyrate and creatinine, but not fructosamine. The results of the study show that heat stress significantly affects reactive oxygen species production and antioxidant parameters. Carotenoid supplementation should be considered to alleviate the impact of these effects.

Total Lipids, Fatty Acid Composition, Total Cholesterol and Lipid-Soluble Antioxidant Vitamins in the longissimus lumborum Muscle of Water Buffalo (Bubalus bubalis) from Different Production Systems of the Brazilian Eastern Amazon.

Simple SummaryThe constant search for higher living standards and better health makes consumers more aware of the nutritional compositions of foods. Water buffalo meat has so far been poorly characterized. In this work, we have analyzed the influence of different production systems in the Eastern Amazon on meat nutritional quality parameters of water buffalo. Meat nutritional value was improved when buffaloes were reared in Marajó Island extensive system during the rainy season, as it had lower levels of cholesterol and higher amounts of α-tocopherol, associated with a higher h/H ratio and a lower index of atherogenic. Also, this meat had lower levels of saturated fatty acids and higher amounts of mono- and polyunsaturated fatty acids. Overall, meat from buffaloes raised in pasture production systems showed better lipid nutritional quality.The aim of this study was to analyze the influence of distinct production systems and seasonal variation in the Brazilian Eastern Amazon on the meat lipid composition of water buffaloes. Water buffaloes were reared in commercial farms in the Eastern Amazon either in extensive systems (Marajó Island, Nova Timboteua and Santarém locations), during rainy or dry seasons, or intensive (feedlot) systems. Animals reared in extensive systems were fed natural pastures, and those reared in feedlots were fed sorghum silage and commercial pellets. Buffaloes were slaughtered and ribeye muscle (longissimus lumborum) samples collected. Lipid-soluble antioxidant vitamins and fatty acids were analyzed. The nutritional value of meat from buffaloes reared in Marajó Island extensive system during the rainy season was higher than that of other systems, as it had lower levels of cholesterol and higher amounts of α-tocopherol associated with higher hypocholesterolaemic/hypercholesterolaemic ratio and lower index of atherogenic. Also, this meat had lower percentages of saturated fatty acids and higher proportions of mono- and polyunsaturated fatty acids (PUFA), particularly n-3 PUFA, with increased PUFA/saturated fatty acids ratio and decreased n-6/n-3 PUFA ratio. However, all extensive systems produced meat with a relatively low index of thrombogenicity values, which is advantageous for human health.

Vitamin E Supplementation and Mitochondria in Experimental and Functional Hyperthyroidism: A Mini-Review.

Mitochondria are both the main sites of production and the main target of reactive oxygen species (ROS). This can lead to mitochondrial dysfunction with harmful consequences for the cells and the whole organism, resulting in metabolic and neurodegenerative disorders such as type 2 diabetes, obesity, dementia, and aging. To protect themselves from ROS, mitochondria are equipped with an efficient antioxidant system, which includes low-molecular-mass molecules and enzymes able to scavenge ROS or repair the oxidative damage. In the mitochondrial membranes, a major role is played by the lipid-soluble antioxidant vitamin E, which reacts with the peroxyl radicals faster than the molecules of polyunsaturated fatty acids, and in doing so, protects membranes from excessive oxidative damage. In the present review, we summarize the available data concerning the capacity of vitamin E supplementation to protect mitochondria from oxidative damage in hyperthyroidism, a condition that leads to increased mitochondrial ROS production and oxidative damage. Vitamin E supplementation to hyperthyroid animals limits the thyroid hormone-induced increases in mitochondrial ROS and oxidative damage. Moreover, it prevents the reduction of the high functionality components of the mitochondrial population induced by hyperthyroidism, thus preserving cell function.

Relation between plasma antioxidant vitamin levels, adiposity and cardio-metabolic profile in adolescents: Effects of a multidisciplinary obesity programme

Invivo and invitro evidence suggests that antioxidant vitamins and carotenoids may be key factors in the treatment and prevention of obesity and obesity-associated disorders. Hence, the objective of the present study was to determine the relationship between plasma lipid-soluble antioxidant vitamin and carotenoid levels and adiposity and cardio-metabolic risk markers in overweight and obese adolescents participating in a multidisciplinary weight loss programme. A therapeutic programme was conducted with 103 adolescents aged 12-17 years old and diagnosed with overweight or obesity. Plasma concentrations of α-tocopherol, retinol, β-carotene and lycopene, anthropometric indicators of general and central adiposity, blood pressure and biochemical parameters were analysed at baseline and at 2 and 6 months of treatment. Lipid-corrected retinol (P<0.05), β-carotene (P=0.001) and α-tocopherol (P<0.001) plasma levels increased significantly, whereas lipid-corrected lycopene levels remained unaltered during the treatment. Anthropometric indicators of adiposity (P<0.001), blood pressure (P<0.01) and biochemical parameters (P<0.05) decreased significantly, whereas fat free mass increased significantly (P<0.001). These clinical and biochemical improvements were related to changes in plasma lipid-corrected antioxidant vitamin and carotenoid levels. The adolescents who experienced the greatest weight loss also showed the largest decrease in anthropometric indicators of adiposity and biochemical parameters and the highest increase in fat free mass. Weight loss in these adolescents was related to an increase in plasma levels of lipid-corrected α-tocopherol (P=0.001), β-carotene (P=0.034) and lycopene (P=0.019). Plasma lipid-soluble antioxidant vitamin and carotenoid levels are associated with reduced adiposity, greater weight loss and an improved cardio-metabolic profile in overweight and obese adolescents.

Effects of 8 weeks of CPAP on lipid‐based oxidative markers in obstructive sleep apnea: a randomized trial

Dyslipidaemia and increased oxidative stress have been reported in severe obstructive sleep apnea, and both may be related to the development of cardiovascular disease. We have previously shown in a randomized crossover study in patients with moderate to severe obstructive sleep apnea that therapeutic continuous positive airway pressure treatment for 8 weeks improved postprandial triglycerides and total cholesterol when compared with sham continuous positive airway pressure. From this study we have now compared the effect of 8 weeks of therapeutic continuous positive airway pressure and sham continuous positive airway pressure on oxidative lipid damage and plasma lipophilic antioxidant levels. Unesterified cholesterol, esterified unsaturated fatty acids (cholesteryl linoleate: C18:2; and cholesteryl arachidonate: C20:4; the major unsaturated and oxidizable lipids in low-density lipoproteins), their corresponding oxidized products [cholesteryl ester-derived lipid hydroperoxides and hydroxides (CE-O(O)H)] and antioxidant vitamin E were assessed at 20:30 hours before sleep, and at 06:00 and 08:30 hours after sleep. Amongst the 29 patients completing the study, three had incomplete or missing [CE-O(O)H] data. The mean apnea -hypopnoea index, age and body mass index were 38 per hour, 49 years and 32 kg m(-2) , respectively. No differences in lipid-based oxidative markers or lipophilic antioxidant levels were observed between the continuous positive airway pressure and sham continuous positive airway pressure arms at any of the three time-points [unesterified cholesterol 0.01 mm, P > 0.05; cholesteryl linoleate: C18:2 0.05 mm, P > 0.05; cholesteryl arachidonate: C20:4 0.02 mm, P = 0.05; CE-O(O)H 2.5 nm, P > 0.05; and lipid-soluble antioxidant vitamin E 0.03 μm, P > 0.05]. In this study, accumulating CE-O(O)H, a marker of lipid oxidation, does not appear to play a role in oxidative stress in obstructive sleep apnea.

Investigation of the phototoxic effect of ZnO nanorods on fibroblasts and melanoma human cells

Photocytotoxic effects of as-grown and zinc oxide (ZnO) nanorods coated with 5-aminolevulinic acid (ALA) have been studied on human cells, i.e. melanoma and foreskin fibroblast, under dark and ultraviolet light exposures. Zinc oxide nanorods have been grown on the very sharp tip (diameter = 700 nm) of borosilicate glass pipettes and then were coated by the photosensitizer for targeted investigations inside human cells. The coated glass pipette’s tip with photosensitizer has been inserted inside the cells with the help of a micro-manipulator and irradiated through ultraviolet light (UVA), which reduces the membrane potential of the mitochondria leading to cell death. Cell viability loss has been detected by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) reduction assay when exposed to the dissolved ZnO nanorods and the production of the reactive oxygen species (ROS) has been detected along with the enhanced cytotoxic effect under UVA irradiation. Additionally, the influence of the lipid soluble antioxidant vitamin E and water-soluble N-acetyl-cysteine toward the enhancement or reduction of the toxicity has been investigated. A comparative analysis of the toxic nature of ZnO nanorods has been drawn between normal human fibroblast and melanoma cells, which can be favorable for understanding the clinical setting for killing tumor cells.

Retinitis pigmentosa and macular degeneration in a patient with ataxia with isolated vitamin E deficiency with a novel c.717 del C mutation in the TTPA gene

Ataxia with isolated vitamin E deficiency (AVED) is a neurodegenerative disease caused by a mutation in the α-tocopherol transfer protein gene (TTPA). The clinical features of the disease resemble Friedreich's ataxia. However, AVED is associated with low plasma vitamin E levels, which results in compromised antioxidant function. Dysregulation of this lipid-soluble antioxidant vitamin plays a major role in the neurodegeneration observed in AVED. Some AVED patients experience decreased visual acuity. Retinitis pigmentosa is thought to be the main cause of this visual impairment. Although antioxidant levels are important for the prevention of macular degeneration, there have been no reports of macular degeneration in AVED. Here, we describe a patient with AVED with progressive macular degeneration, who carried a novel truncating mutation—c.717 del C (p.D239EfsX25)—in exon 5 of the TTPA gene. These findings suggest that this newly identified mutation results in severely low serum vitamin E levels, which may be associated with the development of retinitis pigmentosa and macular degeneration.

Aspartame induces alteration in electrolytes homeostasis of immune organs in wistar albino rats

Aspartame is rapidly and completely metabolized in humans and experimental animals to aspartic acid (40%), phenylalanine (50%) and methanol (10%). Methanol, a toxic metabolite is primarily metabolized by oxidation to formaldehyde and then to formate. These processes are accompanied by the formation of superoxide anion and hydrogen peroxide. This study is focused to understand whether the oral administration of Aspartame (40mg/kg bw) for 15 days, 30 days, and 90 days have any effect on immune organs. Damage to plasma membrane was assessed by levels of membrane-bound ATPases. Oxidative stress status was assessed by alterations in level of lipid peroxides, protein carbonyls, protein thiol and lipid-soluble antioxidant vitamin E. To mimic human methanol metabolism, folate-deficient animals were used. There was decrease in all membrane-bound ATPases activities in immune organs. Aspartame administration to rats inducing excess free radical generation is confirmed by increase in lipid peroxidation, obvious which is also again substantiated by the elevated protein carbonyl and decrease in protein thiol in this study. These excess free radical generations also decrease the cellularity (reduction in organ weight and cell count) of immune organs.

Of GIRK channels, vitamin E transfer, and a vertebrate fluorescent protein

Of GIRK channels, vitamin E transfer, and a vertebrate fluorescent protein

Supplementation of oil palm phenolics in normal healthy human volunteers

In comparison to the lipid‐soluble antioxidants (vitamin E and carotenoids), it has been less known that the oil palm fruit also contains potent water‐soluble antioxidants. MPOB has developed a breakthrough technology in harvesting a substantial amount of phenolic acids from the bio‐aqueous co‐product of oil palm fruit. Based on several emerging evidences from in‐vitro and animal studies postulating the antioxidant effectiveness of oil palm phenolics (OPP), a Phase 1 Clinical Trial was conducted to evaluate physiological effects of the OPP. In this single‐blind, cross‐over design trial, 25 healthy human volunteers were supplemented with 150 mL of control or OPP (concentration at 1500 ppm Gallic acid equivalent, GAE) treatments, twice per day for 60 days recruitment period. Fasting blood and urine samples were collected at day 1, 30 and 60, and medical examination was performed during the trial interventions. All clinical biochemistry profiles values observed throughout the OPP trial recruitment period were in normal range and no major adverse effect occurred. Additionally, OPP supplementation resulted in significantly improving total cholesterol and LDL‐C levels, compared to the control treatment. These current evidences have provided investigators with several outcomes that justify the needs to continue the investigation with the dose‐exploration and phase 2 clinical trials of OPP in the near future.

Nutritional Antioxidants and Lipid Profile in Newly Diagnosed Rheumatoid Arthritis Patients

Introduction: Rheumatoid arthritis (RA) is a chronic progressive autoimmune disorder characterized by symmetric erosive synovitis. The pathogenesis of bone erosion and joint deformities are not fully understood. The aim of this study was to find out vitamin C and E levels along with the lipid profile in newly diagnosed cases of RA. Materials and Methods: The patients for the study were selected from individuals attending the routine checkup in an Outpatient Department. Based on the criteria led by the American Rheumatism Association (ARA), the newly diagnosed patients were taken as cases and other normal individuals were taken as control group in the study. A total of 50 subjects were included in the study with the age group of 48 ± six years for both genders. Serum Vitamin-E was determined by the colorimetric method and serum Vitamin-C was estimated by the dinitro phenyl hydrazine method. Serum total cholesterol, HDL-cholesterol, triglycerides, and VLDL levels were estimated by the enzymatic method. LDL- cholesterol was calculated by the Friedewald's formula. Results: The levels of nutritional antioxidants vitamin E and C were different significantly in RA patients compared to control group. The lipid profile parameters were also different significantly in RA patients compared to the controls. Conclusion: Patients with RA presented with an imbalance in the oxidant-antioxidant system that markedly increased lipid peroxidation products and significantly decreased lipid soluble antioxidant vitamin E. These changes might play a role in the tissue damage and inflammation process in this disease.

Protective effect of vitamin E and epicatechin against nicotine-induced oxidative stress in rats

Nicotine is a major pharmacologically active and addictive component of tobacco smoke, which is regarded to be a primary risk factor in the development of cardiovascular and pulmonary diseases. Epicatechin is one of the most potent antioxidants present in the human diet. Particularly high levels of this compound are found in tea, apples and chocolate. It has been reported that tea extracts and/or its constituents have antibacterial, antiviral, antioxidative, antitumor and antimutagenic activities. Vitamin E is a major lipid-soluble antioxidant vitamin and free radical scavenger, presents as an integral component of cellular membranes and has important biological functions. The primary mechanism by which vitamin E is proposed to prevent cancer is through their antioxidant properties. The goal of this study is to evaluate the effect of epicatechin alone or combined with vitamin E in inhibiting the oxidative stress induced by nicotine in rats. Results obtained indicated that there was a significant elevation in the levels of malondialdhyde (MDA) in nicotine injected rats. The combined treatment (epicatechin + Vit E) group showed a potential reduction of these parameters more than individual treatment. The activities of superoxide dismutase, catalase and glutathione peroxidase were found significantly higher in combined treated than untreated rats. In nicotine group, a negative significant correlation between reduced glutathione and MDA (r = -0.92) was observed. In conclusion, these results suggested that the supplementation of diet with epicatechin and vitamin E provided antioxidant defense with strong chemopreventive activity against nicotine-induced carcinogenesis.

Seasonal changes and muscle type effect on the nutritional quality of intramuscular fat in Mirandesa-PDO veal

The influence of slaughter season and muscle type on the detailed fatty acid composition, including conjugated linoleic acid isomers, and contents of total cholesterol and lipid-soluble antioxidant vitamins (α-tocopherol and β-carotene) in Mirandesa-PDO veal was assessed. Mirandesa purebred calves (n=29) were raised in a traditional production semi-extensive system, slaughtered in late spring (June) or early autumn (October) and the longissimus lumborum and semitendinosus muscles were sampled for analysis. Although the lipid composition of PDO veal was only slightly affected by the slaughter season, it was markedly changed by the muscle type. However, PDO veal had values of pasture-fed cattle for lipid grass intake indicators, in both seasons and muscles. From a human health standpoint, intramuscular fat in Mirandesa-PDO veal has a high nutritional value throughout the year, with favorable ratios of n−6/n−3 and contents of n−3 PUFA and α-tocopherol, as a result of the beneficial effects of grass feeding.

Eight weeks of conjugated linoleic acid supplementation has no effect on antioxidant status in healthy overweight/obese Korean individuals

The aim of this study was to evaluate the effect of CLA supplementation on antioxidant metabolism in healthy overweight/obese Korean individuals. We performed a randomized, double-blind, placebo-controlled trial, where 29 healthy overweight/obese (BMI≥23kg/m(2)) participants (2 men and 27 women) were randomly selected to receive placebo (n=15, 2.4g olive oil/day) or 2.4g/day CLA mixture (n=14, 36.9% of cis-9, trans-11 and 37.9% of trans-10, cis-12) for 8weeks. There were no significant differences in plasma total radical-trapping antioxidant potential (TRAP), lipid peroxidation (conjugated dienes), lipid-soluble antioxidant vitamin concentration, erythrocyte antioxidant enzyme (superoxide dismutase, catalase, glutathione peroxidase) activities, and leukocyte DNA damage between the CLA and placebo groups. The data suggest that short-term supplementation (8weeks) with CLA (2.4g/day) might have no significant effects on lipid peroxidation and antioxidant metabolism.

Effects of Puffer (Sphoeroides rubripes) Supplementation on Disruption of Antioxidant Defense Systems in Ethanol-Treated Rats

We investigated the effects of puffer (Sphoeroides rubripes) supplementation on antioxidant metabolism in ethanol-treated rats. Sprague-Dawley rats were randomly assigned into 4 groups of 7 rats each and fed (1) an AIN-93G diet (NC), (2) 25% ethanol (E), (3) 25% ethanol and an AIN-93G diet containing 1% puffer flesh (E+F), or (4) 25% ethanol and an AIN-93G diet containing 1% puffer skin (E+S) for 5 wk. At the end of the experimental period, the rats were sacrificed and their blood and organs were collected. To evaluate the effect of puffer supplementation, lipid-soluble antioxidant vitamin and conjugated diene (CD) levels, DNA damage, and mRNA expression of heme oxygenase-1 (HO-1) were assessed. Animals that were fed ethanol showed reduced plasma levels of lipid-soluble antioxidant vitamin and significantly increased levels of lipid peroxides, DNA damage, and HO-1 expression. Dietary supplementation with puffer conferred an antioxidant effect by significantly increasing the levels of γ-tocopherol, a lipid-soluble antioxidant vitamin, and by significantly decreasing the plasma levels of CD, DNA damage, and HO-1 expression. These results suggest that consumption of puffer improves the antioxidant status of ethanol-treated rats.

Epigallocatechin-3-gallate (EGCG) affects the antioxidant and immune defense of the rainbow trout, Oncorhynchus mykiss

Epigallocatechin-3-gallate (EGCG), a very potent antioxidant derived from green tea, was compared with vitamin E in terms of its effects on antioxidant defense and immune response of rainbow trout, by means of a feeding trial of eight weeks. Two of the experimental diets were supplemented with EGCG at either 20 or 100 mg kg(-1) diet (which contained only 30% of the intended levels) and the third was provided with 100 mg kg(-1) vitamin E but not EGCG. The control diet was not supplemented with the test components. Observation of tissue levels indicated that the high amount of EGCG helped to increase the availability of the lipid-soluble antioxidant vitamin E. The lower levels of lipid hydroperoxide in the liver of fish fed the higher amount of EGCG suggested that it was an effective antioxidant. Considering the immune indices, EGCG and vitamin E at 100 mg (actual amounts 31.9 and 94.1 mg kg(-1) diet, respectively) had identical capabilities in improving phagocytic activity and controlling hydrogen peroxide production by leucocytes. However, EGCG could possibly be more effective at enhancing serum lysozyme activity and the alternative complement activity. This work revealed the potential of EGCG as an antioxidant and an immunostimulant for rainbow trout, at least at the inclusion level of 32 mg kg(-1) diet.

Engineering tocopherol biosynthetic pathway in Arabidopsis leaves and its effect on antioxidant metabolism

With genetic manipulation, five genes ( HPPD, VTE2, VTE3, VTE1, and VTE4), which encode enzymes involved in tocopherol biosynthesis, were over-expressed in model plant Arabidopsis thaliana, either alone or in couple combinations ( VTE2 + VTE4 and VTE3 + VTE4), to value and compare the roles of enzymes played in tocopherol biosynthetic pathway under the same genetic background. Our results suggested that, elevated expression level of biosynthetic pathway gene affected either total tocopherol content or composition, it is recommended to choose two or more enzymes with different functions for genetic manipulation. It was also found that metabolic engineering of tocopherol biosynthetic pathway affected endogenous ascorbate and glutathione pools in leaves. Further study suggested that expression levels of genes encoding enzymes of Halliwell–Asada cycle were up-regulated, such as APX, DHAR and MDAR. These findings provide hints on the relationship of lipid-soluble antioxidant vitamin E and water-soluble antioxidants vitamin C and glutathione, which will help to perfect theory in plant physiology and give practical instruction for metabolic engineering.

Free radical activity and lipid soluble antioxidant vitamin status in patients with long‐term ileal pouch‐anal anastomosis

OBJECTIVE: Ileal pouch-anal anastomosis (IPAA) is the operation of choice for patients with ulcerative colitis. Free radical activity and the status of lipid soluble antioxidant vitamins have not been previously assessed in patients with IPAA. The aim of the present study was to measure the plasma concentrations of lipophyllic antioxidants and free radical activity in IPAA patients and compare them with normal subjects. METHOD: Forty-eight IPAA patients and 50 healthy controls were studied. A dietary assessment of vitamin E (alpha-tocopherol) and carotene was undertaken and plasma antioxidant status was assessed. Plasma malondialdehyde (MDA) was measured to assess the extent of free radical damage. In IPAA patients, association between the degree of inflammation in the pouch mucosa and the plasma concentration of lipophyllic antioxidants and extent of free radical activity was investigated. RESULTS: The dietary intake of carotene was similar in both groups. Intake of vitamin E was significantly lower in patients than controls (P = 0.01). In the IPAA group plasma concentrations of alpha-carotene, beta-carotene and lycopene were significantly lower (P < 0.001) and alpha-tocopherol:cholesterol ratio significantly higher (P < 0.001). Free radical damage was significantly greater in patients than controls (P < 0.01). There were no significant correlations between the degree of inflammation in the pouch and plasma concentrations of MDA, carotenoids, alpha-tocopherol:cholesterol ratio or intake of vitamins. CONCLUSION: Compared with normal subjects, patients with IPAA have significantly lower plasma concentrations of lipophyllic antioxidants alpha-carotene, beta-carotene and lycopene and higher free radical activity suggesting increased oxidative stress. These differences do not appear to be related to diet and do not correlate with histological severity of pouch inflammation.

Common Variation in the β-Carotene 15,15′-Monooxygenase 1 Gene Affects Circulating Levels of Carotenoids: A Genome-wide Association Study

Low plasma levels of carotenoids and tocopherols are associated with increased risk of chronic disease and disability. Because dietary intake of these lipid-soluble antioxidant vitamins is only poorly correlated with plasma levels, we hypothesized that circulating carotenoids (vitamin A-related compounds) and tocopherols (vitamin E-related compounds) are affected by common genetic variation. By conducting a genome-wide association study in a sample of Italians (n = 1190), we identified novel common variants associated with circulating carotenoid levels and known lipid variants associated with alpha-tocopherol levels. Effects were replicated in the Women's Health and Aging Study (n = 615) and in the alpha-Tocopherol, beta-Carotene Cancer Prevention (ATBC) study (n = 2136). In meta-analyses including all three studies, the G allele at rs6564851, near the beta-carotene 15,15'-monooxygenase 1 (BCMO1) gene, was associated with higher beta-carotene (p = 1.6 x 10(-24)) and alpha-carotene (p = 0.0001) levels and lower lycopene (0.003), zeaxanthin (p = 1.3 x 10(-5)), and lutein (p = 7.3 x 10(-15)) levels, with effect sizes ranging from 0.10-0.28 SDs per allele. Interestingly, this genetic variant had no significant effect on plasma retinol (p > 0.05). The SNP rs12272004, in linkage disequilibrium with the S19W variant in the APOA5 gene, was associated with alpha-tocopherol (meta-analysis p = 7.8 x 10(-10)) levels, and this association was substantially weaker when we adjusted for triglyceride levels (p = 0.002). Our findings might shed light on the controversial relationship between lipid-soluble anti-oxidant nutrients and human health.

Free radical activity and lipid soluble anti‐oxidant vitamin status in patients with long‐term ileal pouch‐anal anastomosis

Ileal pouch-anal anastomosis (IPAA) is the operation of choice for patients with ulcerative colitis. Free radical activity and the status of lipid soluble antioxidant vitamins have not been previously assessed in patients with IPAA. The aim of the present study was to measure the plasma concentrations of lipophyllic antioxidants and free radical activity in IPAA patients and compare them with normal subjects. Forty-eight IPAA patients and 50 healthy controls were studied. A dietary assessment of vitamin E (alpha-tocopherol) and carotene was undertaken and plasma antioxidant status was assessed. Plasma malondialdehyde (MDA) was measured to assess the extent of free radical damage. In IPAA patients, association between the degree of inflammation in the pouch mucosa and the plasma concentration of lipophyllic antioxidants and extent of free radical activity was investigated. The dietary intake of carotene was similar in both groups. Intake of vitamin E was significantly lower in patients than controls (P = 0.01). In the IPAA group plasma concentrations of alpha-carotene, beta-carotene and lycopene were significantly lower (P < 0.001) and alpha-tocopherol:cholesterol ratio significantly higher (P < 0.001). Free radical damage was significantly greater in patients than controls (P < 0.01). There were no significant correlations between the degree of inflammation in the pouch and plasma concentrations of MDA, carotenoids, alpha-tocopherol:cholesterol ratio or intake of vitamins. Compared with normal subjects, patients with IPAA have significantly lower plasma concentrations of lipophyllic antioxidants alpha-carotene, beta-carotene and lycopene and higher free radical activity suggesting increased oxidative stress. These differences do not appear to be related to diet and do not correlate with histological severity of pouch inflammation.