No abstract available.
alpha-Tocopherol* ; beta Carotene* ; Humans ; Retinoids*

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

OBJECTIVES: Some antioxidants are believed to restore dentin bond strength after dental bleaching. This study was done to evaluate the influence of antioxidants on the bond strength of bleached bovine dentin. MATERIALS AND METHODS: Thirty incisors were randomly assigned to 10 groups (two unbleached control and eight bleached groups: immediate bonding IB, 4 wk delayed bonding DB, 10% sodium ascorbate treated SA, 10% alpha-tocopherol treated TP groups). Teeth in half of groups were subjected to thermal stress, whereas the remaining groups were not. Resin-dentin rods with a cross-sectional area of 2.25 mm2 were obtained and microtensile bond strength was determined at a crosshead speed of 1 mm/min. Fifteen specimens were prepared for SEM to compare the surface characteristics of each group. The change in dentin bond strength from thermal stress and antioxidant treatment was evaluated using two-way analysis of variance (ANOVA) and Sheffe's post hoc test at a significance level of 95%. RESULTS: The control group exhibited the highest bond strength values, whereas IB group showed the lowest value before and after thermocycling. The DB group recovered its bond strength similar to that of the control group. The SA and TP groups exhibited similar bond strength values with those of the control and DB groups before thermocycling. However, The TP group did not maintain bond strength with thermal stress, whereas the SA group did. CONCLUSIONS: Applying a 10% sodium ascorbate solution rather than 10% alpha-tocopherol solution for 60 sec is recommended to maintain dentin bond strength when restoring non-vitally bleached teeth.
alpha-Tocopherol ; Antioxidants* ; Ascorbic Acid ; Dentin* ; Incisor ; Tooth ; Tooth Bleaching

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

OBJECTIVE: Our purpose was to investigate lipid peroxide levels, total peroxyl radical-trapping antioxidative parameter (TRAP) values, and antioxidant vitamin levels in placental tissues of women with preeclampsia and to evaluate their roles in the pathophysiology of preeclampsia. STUDY DESIGN: Samples of placental tissue homogenates were obtained from 23 normal and 18 preeclamptic women between 33 and 40 weeks gestation. TNF-alpha was assayed by an enzyme-linked immunoassay. Lipid peroxide levels measured by thiobarbituric acid reaction. The TRAP values were measured by modified Wayners method. Ascorbic acid, uric acid, retinol, alpha-tocopherol, and gamma-tocopherol were measured by high performance liquid chromatography (HPLC) CoulArray detector. RESULTS: TNF-alpha levels in placental tissue homogenates of women with preeclampsia were significantly higher than that of women with preeclampsia (21.4+/-3.39 vs. 10.3+/-1.06 pg/ml, p<0.05). Lipid peroxide levels in placental tissue homogenates of women with preeclampsia were significantly higher than that of women with preeclampsia (6.65+/-0.57 vs. 4.98+/-0.37 nmol/mg protein, p<0.05). TRAP values in placental tissue homogenates of women with preeclampsia were significantly lower than that of women with normal pregnancy (0.24+/-0.02 vs. 0.31+/-0.03 mM, p<0.05). Ascorbic acid levels in placental tissue homogenates of women with preeclampsia were significantly lower than that of women with normal pregnancy (217.0+/-21.0 vs. 333.3+/-32.8 nmol/ml, p<0.05). CONCLUSION: The above results suggest that increased oxidative stress in placenta is involved in the pathophysiology of preeclampsia and ascorbic acid may act as an important preventive factor in the development of preeclampsia.
alpha-Tocopherol ; Ascorbic Acid ; Chromatography, Liquid ; Female ; gamma-Tocopherol ; Humans ; Immunoassay ; Oxidative Stress ; Placenta* ; Pre-Eclampsia* ; Pregnancy* ; Tumor Necrosis Factor-alpha ; Uric Acid ; Vitamin A ; Vitamins

OBJECTIVE: This study assesses the hypothesis that preeclampsia is associated with the change of oxidative system balance by measuring the lipid peroxidation and antioxidant activity in preeclampsia. METHOD: Venous blood samples were collected from twenty women with preeclampsia and twenty women with uncomplicated pregnancies. Total lipid peroxidation, total antioxidant activity, antioxidant enzyme activity and antioxidant concentration were measured using flow injection-chemiluminescent method. RESULTS: 1. Total lipid peroxidation(PCOOH) was higher in preeclampsia(717.22+/-93.08 pmol/ml) than in normal pregnant(486.86+/-43.15 pmol/ml) (P<0.05). 2. Total antioxidant activity was significantly higher in preeclampsia(46.02+/-5.95 % inhibition) than in normal pregnant(38.59+/-7.57 % inhibition) (P<0.05).3. Antioxidant enzyme, catalase activity in RBC was lower in preeclampsia(346.59+/-82.84 unit/gHb) than in normal pregnant(440.62+/-72.8 unit/gHb) (P<0.05).4. Antioxidant, alpha-tocopherol concentration in RBC was slightly lower in preeclampsia(33.21+/-7.82 ng/gHb) than in normal pregnant(36.06+/-6.86 ng/gH), but there was no statistically significant difference (P<0.05). CONCLUSION: This data seems to show that preeclampsia is associated with an imbalance between the lipid peroxidation and the antioxidant system.
alpha-Tocopherol ; Catalase ; Female ; Free Radicals ; Humans ; Lipid Peroxidation ; Pre-Eclampsia* ; Pregnancy

Generally, the postoperative failure of glaucoma filtrationsurgery(GFS) is caused by scarring of filtering site. Mitomycin C(MMC) has been commonly used for preventing the scarring of filtering site. Though the antifibroblastic effect of this drug is approved clinically, its cytotoxic side effect cannot be overlooked,. alpha-tocopherol is known to inhibit proliferation of fibroblast without cytotoxic complications. In this study, we used alpha-tocopherol in GFS of rabbits and investigated the maintenance of bleb formation, complications and inhibition of fibroblast proliferation compared with MMC. Thirty six rabbits were divided into 6 groups Negative control groups were the balanced salt solution soaked group and the 19% ethanol soaked group and positive control group was soaked with 0.2mg/ml MMC during GFS. As experimental groups, group I, II, III were soaked with 100micrometer, 1mM and 10mM alpha-tocopherol. The results were as follows: For the maintenance of bleb formation, at postoperative 2 weeks, all extinguished in negative control groups and each experimental groups from I to III showed 16.7%, 33.3%, 50%, with highest rate of 66.7% in MMC soaked group, but at 2 months, group III and MMC soaked group showed 33.3% equally. Various complications were present in MMC soaked group but rare in alpha-tocopherol soaked groups. On histologic examinations, proliferation of fibroblast and infiltration of lymphocyte in group II, III and MMC soaked group except group I were much less than those of negative control groups and the degree of inhibition was proportional to concentration of tocopherol. There was no statistic difference(P>0.05) in area of reticulin fibers between group III and MMC soaked group and antifibroblastic effects were also similar between these two groups. These result suggest when directlyconcentration(1mM<) as much as MMC. Moreover, it is expected to be used more safely during GFS withous serious cytotoxic complications. However, application method, dosageand possible long term complications.
alpha-Tocopherol* ; Blister ; Cicatrix ; Ethanol ; Fibroblasts* ; Filtering Surgery* ; Filtration* ; Glaucoma* ; Lymphocytes ; Mitomycin ; Rabbits* ; Reticulin ; Tocopherols

This work describes the pharmacological inhibition by KR 31378 and its acetyl metabolite, KR 31612, of the apoptotic cell death induced by H2O2 in the A7r5 cells. Exposure of A7r5 cells to H2O2 (0.5 mM) induced a concentration-dependent cytotoxicity in association with oligonucleosomal DNA fragmentation. H2O2-induced cell death was potently suppressed by KR 31378, KR 31612, alpha-tocopherol or trolox. Additionally, the apoptotic death of A7r5 cells (DNA ladders on electrophoresis) was also strongly suppressed by KR 31378 and KR 31612, but to a less degree by alpha-tocopherol and trolox. As a mechanistic study, incubation with H2O2 markedly showed a decreased Bcl-2 level and, in contrast, increased Bax protein and cytochrome C release, which were significantly and concentration-dependently reversed by KR 31378 and KR 31612 as well as by alpha-tocopherol and trolox. KR 31378 and alpha-tocopherol significantly reduced lipid peroxidation in accordance with reduced intracellular ROS and peroxyl radical. These results suggest that KR 31378 has a therapeutic potential against the apoptotic injury via mediation of antioxidative stress.
alpha-Tocopherol ; bcl-2-Associated X Protein ; Cell Death ; Cytochromes c ; DNA Fragmentation ; Lipid Peroxidation ; Negotiating

OBJECTIVE: The aim of this study was to evaluate the effects of vitamin E (alpha-tocopherol) administration on bone formation in response to expansion of the inter-premaxillary suture, in rats, histomorphometrically. METHODS: Thirty 50 - 60 day old Wistar rats were separated into five equal groups (one control and four experimental). All groups were subjected to inter-premaxilla expansion with 50-gram of force. Six control animals received saline solution (Group I) and three experimental groups were treated with a single dose of alpha-tocopherol injected into the inter-premaxillary suture after one day after appliance placement (Group II: 2 mg/kg; Group III: 10 mg/kg; and Group IV: 50 mg/kg). A further group of six animals received three injections of 10 mg/kg alpha-tocopherol, one each on days 3, 6, and 9 (Group V). Bone formation in the suture was evaluated by bone histomorphometry. Kruskal-Wallis rank and Mann-Whitney U tests were used for statistical evaluation at p<0.05 level. RESULTS: New bone area, bone perimeter, feret's diameter and newly formed bone measurements were significantly higher in the experimental groups than the control (p<0.001). Bone architecture in alpha-tocopherol administrated groups was improved, and bone formation during the expansion period was stimulated significantly, in a dose-dependent manner. CONCLUSIONS: The application of alpha-tocopherol during the early stages to orthopedically expanded inter-premaxillary suture areas may stimulate bone formation and shorten the retention period, in rats.
alpha-Tocopherol ; Animals ; Osteogenesis ; Rats ; Rats, Wistar ; Retention (Psychology) ; Sodium Chloride ; Sutures ; Vitamin E ; Vitamins