Vitamin E has been a generic term for all tocopherol and tocotrienol derivatives. The most active form of vitamin E isoforms in vivo is regarded to be alpha-tocopherol which is the only form defined as vitamin E in the US Food and Nutrition Board, causing controversy over setting dietary reference intake (DRI) of vitamin E. However, most of the countries other than the US maintain the original concept that all isoforms are accepted as vitamin E but with different biopotency. The roles of the isoforms of vitamin E other than alpha-tocopherol have received continuous attention. Among them those of gamma-tocopherol and alpha-tocotrienol have been most studied in comparison with alpha-tocopherol, since gamma-tocopherol comprises major form of vitamin E in many plant seeds and those of the both vitamin E have been implicated in unique physiological functions. This review summarizes findings that have led a better understanding of vitamin E absorption, transport, tissue storage and various functions common and specific to vitamin E isoforms focusing alpha- and gamma-tocopherol as well as tocotrienols. It is expected to help redefining vitamin E and setting its DRI for Koreans.
Absorption ; alpha-Tocopherol ; gamma-Tocopherol ; Plants ; Protein Isoforms ; Seeds ; Tocopherols ; Tocotrienols ; Vitamin E ; Vitamins

The purpose of this project was to evaluate whether vitamin E supplementation could improve the antioxidant status and lymphocyte DNA damage in Korean postmenopausal women. This was double blinded, placebo-controlled trial. Thirty-five subject were randomized to receive either placebo 400 mg/capsule or natural alpha-tocopherol 400 IU/capsule, 2 times a day for 6 weeks. We measured plasma vitamin C, alpha-tocopherol, gamma-tocopherol, alpha-carotenoid, beta-carotenoid, lycopene concentration and tail length, %DNA in tail, tail moment in lymphocyte DNA damage index. Vitamin E supplementation group had significantly increased plasma vitamin C (p < 0.05), alpha-tocopherol (p < 0.000), whereas gamma-tocopherol (p < 0.000) and tail length (p < 0.05) were significantly decreased. However, placebo supplementation group also had significantly increased plasma vitamin C (p < 0.05). In conclusion, our study shows that vitamin E supplementation to Korean postmenopausal women may partially improve antioxidant status and lymphocyte DNA damage.
alpha-Tocopherol* ; Ascorbic Acid ; DNA Damage* ; DNA* ; Female ; gamma-Tocopherol ; Humans ; Lymphocytes* ; Plasma ; Vitamin E ; Vitamins

The elevated level of circulating estradiol increases the risk of breast tumor development. To gain further insight into mechanisms involved in their actions, we investigated the molecular mechanisms of 4-hydroxyestradiol (4-OHE2) to initiate and/or promote abnormal cell growth, and of alpha- or gamma-tocopherol to inhibit this process. MCF-10A, human breast epithelial cells were incubated with 0.1 microM 4-OHE2, either with or without 30 microM tocopherols for 96 h. 4-OHE2 caused the accumulation of intracellular ROS, while cellular GSH/GSSG ratio and MnSOD protein levels were decreased, indicating that there was an oxidative burden. 4-OHE2 treatment also changed the levels of DNA repair proteins, BRCA1 and PARP-1. gamma-Tocopherol suppressed the 4-OHE2-induced increases in ROS, GSH/GSSG ratio, and MnSOD protein expression, while alpha-tocopherol up-regulated BRCA1 and PARP-1 protein expression. In conclusion, 4-OHE2 increases oxidative stress reducing the level of proteins related to DNA repair. Tocopherols suppressed oxidative stress by scavenging ROS or up-regulating DNA repair elements.
alpha-Tocopherol ; Breast ; Breast Neoplasms ; DNA Damage ; DNA Repair ; Epithelial Cells ; Estradiol ; Estrogens, Catechol ; gamma-Tocopherol ; Humans ; Oxidative Stress ; Proteins ; Tocopherols

OBJECTIVE: This controlled trial investigated the effect of supplementation with vitamins C and E on the lipid peroxide, antioxidant ability, and antioxidant vitamin levels in full term maternal and umbilical venous plasma. METHODS: Forty pregnant women were randomized in this study. They were nulliparous or multiparous women with history of preeclampsia or preterm premature rupture of membranes (PPROM). Twenty women were given vitamin C (1,000 mg/day) and vitamin E (400 IU/day) from 15~20 gestational weeks to delivery. The others were not given, as a control group. Maternal venous blood was obtained before vitamin supplementation and just before delivery. Umbilical venous blood was obtained after delivery. Lipid peroxide level and oxygen-radical absorbance capacity (ORAC) were measured by thiobarbituric acid reaction and Cao's method, respectively. Ascorbic acid, uric acid, beta-carotene, retinol, alpha-tocopherol, and gamma-tocopherol were measured by high performance liquid chromatography. Results: Supplementation with vitamins C and E was associated with decrease in lipid peroxide levels and increase in ORAC values and alpha-tocopherol levels in maternal venous plasma. And it was also associated with decrease in lipid peroxide levels and increase in ORAC values and alpha-tocopherol levels in umbilical venous plasma. CONCLUSION: Supplementation with vitamins C and E may be beneficial in the prevention of oxidant-antioxidant imbalance origin diseases such as preeclampsia, PPROM. And it also may affect antioxidant ability of the fetus.
alpha-Tocopherol ; Ascorbic Acid ; beta Carotene ; Female ; Fetus ; gamma-Tocopherol ; Humans ; Membranes ; Plasma ; Pre-Eclampsia ; Pregnant Women ; Rupture ; Thiobarbiturates ; Uric Acid ; Vitamin A ; Vitamin E ; Vitamins

OBJECTIVE: This study was aimed to investigate lipid peroxide levels, oxygen-radical absorbance capacity (ORAC), and antioxidant vitamin levels in uterine venous plasma, umbilical venous and arterial plasma and to evaluate their roles in the pathophysiology of preeclampsia and effects of oxidative stress on fetus. METHODS: Samples of uterine venous plasma before and after delivery, umbilical venous and arterial plasma were collected from 18 normal and 16 preeclamptic women between 34 and 38 weeks gestation during Cesarean section. Lipid peroxide levels were measured by thiobarbituric acid reaction. The ORAC values were measured by Cao's method. Ascorbic acid, retinol, alpha-tocopherol, and gamma-tocopherol were measured by high performance liquid chromatography. RESULTS: 1. Lipid peroxide levels in uterine venous plasma before and after delivery of women with preeclampsia were significantly higher than that of women with normal pregnancy (5.56 +/- 0.57 vs. 3.48 +/- 0.29, p<0.01, 5.37 +/- 0.41 vs. 3.93 +/- 0.38 nmol/mg protein, p<0.01). 2. Lipid peroxide levels in umbilical venous and arterial plasma of women with preeclampsia were significantly higher than that of women with normal pregnancy (7.32 +/- 0.55 vs. 5.18 +/- 0.38, p<0.01, 8.21 +/- 0.81 vs. 5.14 +/- 0.39 nmol/mg protein, p<0.01). Lipid peroxide levels in umbilical arterial plasma were significantly higher than that of umbilical venous plasma of women with preeclampsia (8.21 +/- 0.81 vs. 7.32 +/- 0.55 nmol/mg protein, p<0.05). 3. The ORAC values in uterine venous plasma before delivery of women with preeclampsia were significantly lower than that of women with normal pregnancy (10993.8 +/- 622.2 vs. 12596.1 +/- 726.1 U/mL, p<0.05). 4. The ORAC values in umbilical venous plasma of women with preeclampsia were significantly lower than that of women with normal pregnancy (10515.1 +/- 683.4 vs. 12804.6 +/- 463.7 U/mL, p<0.05). 5. Ascorbic acid levels in uterine venous plasma before and after delivery of women with preeclampsia were significantly lower than that of women with normal pregnancy (419.2 +/- 64.6 vs. 551.4 +/- 57.6 nmol/mL, p<0.05, 398.1 +/- 45.2 vs. 450.8 +/- 33.6 nmol/mL, p<0.05). 6. Ascorbic acid levels in umbilical venous plasma of women with preeclampsia were significantly lower than that of women with normal pregnancy (401.8 +/- 47.8 vs. 561.4 +/- 53.1 nmol/mL p<0.05). Uric acid levels in umbilical venous plasma of women with preeclam psia were significantly higher than that of women with normal pregnancy (7789.2 +/- 551.7 vs. 6419.5 +/- 452.2 nmol/mL p<0.05). CONCLUSION: The above results suggest that increased oxidative stress in uteroplacental unit is involved in the pathophysiology of preeclampsia and ascorbic acid may act as an important preventive factor in the development of preeclampsia.
alpha-Tocopherol ; Antioxidants ; Ascorbic Acid ; Cesarean Section ; Chromatography, Liquid ; Female ; Fetal Blood ; Fetus ; gamma-Tocopherol ; Humans ; Oxidative Stress ; Plasma* ; Pre-Eclampsia* ; Pregnancy ; Uric Acid ; Vitamin A ; Vitamins*

OBJECTIVE: Our purpose was to investigate Interleukin-6 (IL-6), tumor necrotic factor-alpha (TNF-alpha), lipid peroxide levels, oxygen-radical absorbance capacity (ORAC), and antioxidant levels in umbilical venous blood plasma and to evaluate the roles of them in the pathophysiology of preeclampsia. STUDY DESIGN: Samples of umbilical venous plasma were obtained from 20 normal and 20 preeclamptic women between 33 and 40 weeks gestation. IL-6 and TNF-alpha was assayed by an enzyme-linked immunoassay. Lipid peroxide levels were measured by thiobarbituric acid reaction. The ORAC values were measured by Cao's method. Ascorbic acid, retinol, alpha-tocopherol, and gamma-tocopherol were measured by high performance liquid chromatography. RESULTS: There was no significant differences of IL-6 levels in umbilical venous plasma between women with normal and preeclampsia (2.79+/-0.21 vs. 2.94+/-0.17 ng/ml). TNF-alpha levels in umbilical venous plasma of women with preeclampsia were significantly higher than that of women with preeclampsia (3.04+/-0.01 vs. 1.40+/-0.01 ng/ml, p<0.01). Lipid peroxide levels in umbilical venous plasma of women with preeclampsia were significantly higher than that of women with normal pregnancy (7.32+/-0.09 vs. 5.18+/-0.14, p<0.01). The ORAC values in umbilical venous plasma of women with preeclampsia were significantly lower than that of women with normal pregnancy (12,836.5+/-249.4 vs. 10,490.2+/-276.9 U/ml, p<0.05). Ascorbic acid levels in umbilical venous plasma of women with preeclampsia were significantly lower than those of women with normal pregnancy (320.2+/-48.5 vs. 538.5+/-68.2 nmol/ml, p<0.05). CONCLUSION: The above results in umbilical venous plasma suggest that the imbalance of lipid peroxidation and antioxidant activity in placenta is involved in the pathophysiology of preeclampsia. Increased TNF-alpha in the umbilical venous plasma showed inflammatory reaction in the placenta would be one of the cause of preclampsia. An antioxidant vitamin, ascorbic acid, may act an important antioxidant factor in preeclampsia.
alpha-Tocopherol ; Ascorbic Acid ; Chromatography, Liquid ; Female ; gamma-Tocopherol ; Humans ; Immunoassay ; Interleukin-6* ; Lipid Peroxidation ; Placenta ; Plasma* ; Pre-Eclampsia* ; Pregnancy ; Tumor Necrosis Factor-alpha* ; Vitamin A ; Vitamins

BACKGROUND/OBJECTIVES: Vitamin E is a fat-soluble vitamin and functions primarily as a lipid antioxidant. Inadequate vitamin E status may increase risk of several chronic diseases. Thus, the objectives of this study were to estimate intake and plasma concentration of each tocopherol and to evaluate vitamin E status of Korean adults. SUBJECTS/METHODS: Three consecutive 24-h food recalls and fasting blood samples were collected from healthy 20- to 59-y-old adults (33 males and 73 females) living in the Seoul metropolitan area, South Korea. alpha-, beta-, delta-, and gamma-tocopherol intakes and plasma concentrations of tocopherols (alpha-, delta-, and gamma-tocopherol) were analyzed by gender. RESULTS: Dietary vitamin E and total vitamin E intake (dietary plus supplemental vitamin E) was 17.68 +/- 14.34 and 19.55 +/- 15.78 mg alpha-tocopherol equivalents, respectively. The mean daily alpha-tocopherol, and gamma-tocopherol intakes were 3.07 +/- 2.27 mg and 5.98 +/- 3.74 mg, respectively. Intakes of total vitamin E and each tocopherol of males were significantly higher than those of females (P < 0.05). Plasma alpha-tocopherol concentration was 15.45 +/- 10.16 of males and 15.00 +/- 4.54 micromol/L of females, respectively. There were no significant differences in plasma tocopherol concentrations by gender (P > or = 0.05). Plasma alpha-tocopherol was negatively correlated with gamma-tocopherol intake (P < 0.05). Twenty-three percent of the subjects had plasma alpha-tocopherol concentrations < 12 micromol/L indicating a biochemical deficiency of vitamin E. Approximately 8% and 9% of these participants had plasma alpha-tocopherol:total lipid ratio less than 1.59 micromol/mmol and plasma alpha-tocopherol:total cholesterol ratio less than 2.22 micromol/mmol, respectively, which are also indicative of vitamin E deficiency. CONCLUSIONS: Vitamin E intakes of Korean adults were generally adequate with the Korean Dietary Reference Intakes for vitamin E. However, alpha-tocopherol intake was lower than that reported in other countries, and 23% of the subjects in the current study were vitamin E deficient based on plasma alpha-tocopherol concentrations.
Adult* ; alpha-Tocopherol ; Cholesterol ; Chronic Disease ; Fasting ; Female ; gamma-Tocopherol ; Humans ; Korea ; Male ; Middle Aged* ; Plasma ; Recommended Dietary Allowances ; Seoul ; Tocopherols ; Vitamin E Deficiency ; Vitamin E* ; Vitamins*

BACKGROUND/OBJECTIVES: Vitamin E is a fat-soluble vitamin and functions primarily as a lipid antioxidant. Inadequate vitamin E status may increase risk of several chronic diseases. Thus, the objectives of this study were to estimate intake and plasma concentration of each tocopherol and to evaluate vitamin E status of Korean adults. SUBJECTS/METHODS: Three consecutive 24-h food recalls and fasting blood samples were collected from healthy 20- to 59-y-old adults (33 males and 73 females) living in the Seoul metropolitan area, South Korea. alpha-, beta-, delta-, and gamma-tocopherol intakes and plasma concentrations of tocopherols (alpha-, delta-, and gamma-tocopherol) were analyzed by gender. RESULTS: Dietary vitamin E and total vitamin E intake (dietary plus supplemental vitamin E) was 17.68 +/- 14.34 and 19.55 +/- 15.78 mg alpha-tocopherol equivalents, respectively. The mean daily alpha-tocopherol, and gamma-tocopherol intakes were 3.07 +/- 2.27 mg and 5.98 +/- 3.74 mg, respectively. Intakes of total vitamin E and each tocopherol of males were significantly higher than those of females (P < 0.05). Plasma alpha-tocopherol concentration was 15.45 +/- 10.16 of males and 15.00 +/- 4.54 micromol/L of females, respectively. There were no significant differences in plasma tocopherol concentrations by gender (P > or = 0.05). Plasma alpha-tocopherol was negatively correlated with gamma-tocopherol intake (P < 0.05). Twenty-three percent of the subjects had plasma alpha-tocopherol concentrations < 12 micromol/L indicating a biochemical deficiency of vitamin E. Approximately 8% and 9% of these participants had plasma alpha-tocopherol:total lipid ratio less than 1.59 micromol/mmol and plasma alpha-tocopherol:total cholesterol ratio less than 2.22 micromol/mmol, respectively, which are also indicative of vitamin E deficiency. CONCLUSIONS: Vitamin E intakes of Korean adults were generally adequate with the Korean Dietary Reference Intakes for vitamin E. However, alpha-tocopherol intake was lower than that reported in other countries, and 23% of the subjects in the current study were vitamin E deficient based on plasma alpha-tocopherol concentrations.
Adult* ; alpha-Tocopherol ; Cholesterol ; Chronic Disease ; Fasting ; Female ; gamma-Tocopherol ; Humans ; Korea ; Male ; Middle Aged* ; Plasma ; Recommended Dietary Allowances ; Seoul ; Tocopherols ; Vitamin E Deficiency ; Vitamin E* ; Vitamins*

OBJECTIVE: Our purpose was to investigate lipid peroxide levels, total peroxyl radical-trapping antioxidative parameter (TRAP) values, and antioxidant vitamin levels in the maternal venous blood plasma of preterm premature rupture of membranes (PPROM) and to evaluate their roles of pathophysiology in PPROM. METHODS: Samples of maternal blood were obtained from women with normal pregnancy (n=23) and PPROM (n=20). Lipid peroxide levels of maternal venous blood plasma were measured by thiobarbituric acid reaction. The TRAP value of maternal venous blood plasma was measured by Wayner's method, although some reaction conditions were modified. Ascorbic acid and uric acid were measured by high performance liquid chromatography (HPLC) CoulArray detector of water-soluble antioxidants. Retinol, alpha-tocopherol, and gamma-tocopherol were measured by HPLC-CoulArray detector of fat-soluble vitamins RESULTS: Lipid peroxide levels in the maternal venous blood plasma of PPROM were significantly higher than that of normal pregnancy (3.87 +/- 0.24 vs. 3.04 +/- 0.24 nmol/mg protein, p<0.05). TRAP values in the maternal venous blood plasma of PPROM were significantly lower than that of normal pregnancy (0.33 +/- 0.02 vs. 0.40 +/- 0.02 mM, p<0.05). Ascorbic acid levels in the maternal venous blood plasma of PPROM were significantly lower than that of normal pregnancy (383.8 +/- 47.5 vs. 563.3 +/- 73.8 nmol/mg, p<0.05). There were no significant differences in maternal venous blood plasma uric acid, retinol, alpha-tocopherol, and gamma-tocopherol levels between two groups. CONCLUSION: This findings suggest that the imbalance of increased lipid peroxidation and decreased antioxidant activity in maternal blood may be involved in the pathophysiology of PPROM. Low levels of ascorbic acid in maternal blood appears to be an important determinant of PPROM.
alpha-Tocopherol ; Antioxidants ; Ascorbic Acid ; Chromatography, Liquid ; Female ; gamma-Tocopherol ; Humans ; Lipid Peroxidation* ; Membranes* ; Plasma* ; Pregnancy ; Rupture* ; Uric Acid ; Vitamin A ; Vitamins*

OBJECTIVE: Our purpose was to investigate lipid peroxide levels, total peroxyl radical-trapping antioxidative parameter (TRAP) values, and antioxidant vitamin levels in the maternal venous blood plasma of preterm premature rupture of membranes (PPROM) and to evaluate their roles of pathophysiology in PPROM. METHODS: Samples of maternal blood were obtained from women with normal pregnancy (n=23) and PPROM (n=20). Lipid peroxide levels of maternal venous blood plasma were measured by thiobarbituric acid reaction. The TRAP value of maternal venous blood plasma was measured by Wayner's method, although some reaction conditions were modified. Ascorbic acid and uric acid were measured by high performance liquid chromatography (HPLC) CoulArray detector of water-soluble antioxidants. Retinol, alpha-tocopherol, and gamma-tocopherol were measured by HPLC-CoulArray detector of fat-soluble vitamins RESULTS: Lipid peroxide levels in the maternal venous blood plasma of PPROM were significantly higher than that of normal pregnancy (3.87 +/- 0.24 vs. 3.04 +/- 0.24 nmol/mg protein, p<0.05). TRAP values in the maternal venous blood plasma of PPROM were significantly lower than that of normal pregnancy (0.33 +/- 0.02 vs. 0.40 +/- 0.02 mM, p<0.05). Ascorbic acid levels in the maternal venous blood plasma of PPROM were significantly lower than that of normal pregnancy (383.8 +/- 47.5 vs. 563.3 +/- 73.8 nmol/mg, p<0.05). There were no significant differences in maternal venous blood plasma uric acid, retinol, alpha-tocopherol, and gamma-tocopherol levels between two groups. CONCLUSION: This findings suggest that the imbalance of increased lipid peroxidation and decreased antioxidant activity in maternal blood may be involved in the pathophysiology of PPROM. Low levels of ascorbic acid in maternal blood appears to be an important determinant of PPROM.
alpha-Tocopherol ; Antioxidants ; Ascorbic Acid ; Chromatography, Liquid ; Female ; gamma-Tocopherol ; Humans ; Lipid Peroxidation* ; Membranes* ; Plasma* ; Pregnancy ; Rupture* ; Uric Acid ; Vitamin A ; Vitamins*