Erythrocyte lipid peroxidation, glutathione and vitamin E levels in cholesterol-fed rats

Erythrocyte cholesterol and phospholipid levels, the susceptibility of erythrocytes to lipid peroxidation as well as erythrocyte glutathione and vitamin E levels were determined in rats fed a high cholesterol (2%, w/w) and high cholic acid (0.5%, w/w) diet for 3 months. Cholesterol feeding caused an increase in erythrocyte cholesterol levels, but no change was observed in erythrocyte phospholipid levels. Dietary cholesterol did not alter the susceptibility of erythrocytes to lipid peroxidation as well as erythrocyte glutathione and vitamin E levels in rats.     

维生素C和维生素E对糖尿病大鼠非酶糖化和过氧化反应的影响

以链脲佐菌素腹腔注射ＳＤ大鼠建立糖尿病动物模型，在纯营养素饲料配方中补充维生素Ｃ和／或维生素Ｅ，喂饲周，观察单独或联合补充维生素Ｃ、维生素Ｅ对糖尿病非酶糖化及过氧化的干预作用。结果显示维生素Ｃ和Ｅ联合补充可显著减少糖尿病大鼠血红蛋白、低「密度脂蛋白及肾脏皮质的糖化终产物（ＡＧＥｓ）含量，同时显著降低脂质过氧化产物丙二醛（ＭＤＡ）水平，单独补充维生素Ｃ或维生素Ｅ能显著降低糖尿病鼠血清及肾脏ＭＤＡ含量     

核黄素缺乏大鼠红细胞维生素E水平的变化及脂质过氧化关系的研究

对两组大鼠分别喂饲核黄素缺乏（ＲＤ）膳和核黄素添加（Ｒ８，２２ｍｇ／ｋｇ饲料）膳８周后，测定了两组大鼠的红细胞维生素Ｅ（ＲＢＬＶｅ）、红细胞超氧化物歧化酶（ＳＯＤ）和红细胞丙二醛（ＭＤＡ）的水平。结果发现：ＲＤ组ＲＢＣＶｅ水平（４．７１７３±０．７７１０ｍｇ／ｇ蛋白质）显著低于ＲＳ组（５。３８６８±１．１５３７ｍｇ／ｇ蛋白质，Ｐ＜０．０５）。而ＲＤ组的ＲＢＣＳＯＤ（７７４５．２±６１０．１ｕ／ｇ蛋白质）和ＭＤＡ（０．６８６８±０．１３７２μｇ／ｇ蛋白质）则分别显著低于和高于ＲＳ组（８２６８．５±３０１．０ｎｕ／ｇ蛋白质，０．５５４８±０．０９８０，Ｐ＜０．０５）。研究提示，核黄素缺乏引起细胞膜脂质过氧化加重可能ＲＢＣＶｅ消耗增加。     

Vitamin E and vitamin C plasma levels in premature infants following supplementation of vitamin C

Our preliminary data suggest that supplementation of premature neonates with vitamin C is required to maintain adequate ascorbate plasma levels and may have a sparing effect on vitamin E metabolism. Further studies are required to validate our findings and evaluate the possible antioxidant advantage of ascorbic acid administration.     

Ⅱ型糖尿病患者维生素C、E营养状况及红细胞SOD活性的相关性

为了解非胰岛素依赖型糖尿病(Ⅱ型糖尿病,NIDDM)患VitC．E的摄入及营养状况,进一步观察血浆VitC、E含量及其与SOD的关系,对37例住院NIDDM患的膳食及血浆VitC、E营养状况进行调查,并对其血浆VitC、E含量及红细胞SOD活性进行相关分析。     

Effect of different vitamin E levels on lipid peroxidation in streptozotocin-diabetic rats.

Administration of streptozotocin is used to induce diabetes in experimental models, causing a selective destruction of pancreatic beta islet cells associated with generation of free radicals. Supplementation with antioxidant vitamins such as vitamin E is a protective factor against free radicals. The objective of this study was to determine the effect of administration of a diet supplemented with, or deficient in vitamin E to streptozotocin diabetic rats, controlled or not with insulin, on plasma glucose, hepatic vitamin E and hepatic thiobarbituric acid reactive substance (TBARS) levels before streptozotocin and 24 hours and one and two weeks after drug administration. Deficiency of vitamin E alone increased TBARS levels, and streptozotocin elevated TBARS two times in deficient groups, regardless of insulin control. In rats supplemented with vitamin E, a reduction of plasma glucose and liver vitamin E was observed two weeks after streptozotocin administration (p < 0.05). In conclusion, vitamin E supplementation probably protected against lipoperoxidation and contributed to the absence of elevation of plasma glucose levels, and vitamin E deficiency produced an increase in hepatic TBARS levels in streptozotocin diabetic rats.     

隧道作业人员脂质过氧化水平及口服维生素C和维生素E的防护效果

目的探讨隧道作业人员脂质过氧化水平,以及口服维生素C、维生素E降低脂质过氧化危害的效果。方法检测某在建铁路50名隧道作业人员(实验组)和50名桥梁作业人员(对照组)体内血浆维生素C、维生素E、过氧化脂质(PLPO)含量及红细胞过氧化脂质(ELPO)含量、红细胞超氧化物歧化酶(ESOD)活力、红细胞过氧化氢酶(ECAT)活力、红细胞谷胱甘肽过氧化物酶(EGSHPx)活力。结果实验组血浆维生素C、维生素E、ESOD、ECAT、EGSHPx的含量或活力分别为(40.320±4.699)、(11.174±1.558)μgml和(22996.77±2933.08)UgHb、(13.005±1.751)UmgHb、(65.193±8.531)UgHb,较对照组[分别为(43.596±5.080)、(13.165±2.901)μgml和(24321.05±2178.12)UgHb、(14.722±2.760)UmgHb、(69.000±8.452)UgHb]明显降低,差异有统计学意义(P<0.05),实验组PLPO、ELPO含量分别为(5.514±0.579)、(11.059±2.940)nmolml,较对照组[分别为(5.014±0.957)、(9.232±2.695)nmolml]明显升高,差异有统计学意义(P<0.05)。隧道作业人员服用维生素C、维生素E后,其体内ESOD、ECAT、EGSHPx活力分别较服用前明显升高,PLPO、ELPO含量分别较服用前明显降低,差异均有统计学意义(P<0.01)。结论隧道作业人员体内氧化和抗氧化平衡失调,过氧化和脂质过氧化加剧;补充一定剂量的维生素C、维生素E能有效降低隧道作业人员体内过氧化和脂质过氧化危害。     

Effects of vitamin C and vitamin E on in vivo lipid peroxidation: results of a randomized controlled trial

BACKGROUND: Lipid peroxidation may be important in the pathogenesis of atherosclerosis, particularly in its earliest stages. Evidence predominantly from in vitro studies suggests that antioxidant vitamins can prevent lipid peroxidation and that vitamin C and vitamin E have synergistic effects. However, in vivo evidence in support of these hypotheses is sparse. OBJECTIVE: The objective was to determine the effects of vitamin C and vitamin E, alone or in combination, on in vivo lipid peroxidation. DESIGN: We conducted a placebo-controlled, 2 x 2 factorial trial of vitamin C (500 mg ascorbate/d) and vitamin E (400 IU RRR-alpha-tocopheryl acetate/d) supplementation in 184 nonsmokers. The mean duration of supplementation was 2 mo. The outcome measures were changes from baseline in urinary 8-iso-prostaglandin F(2alpha), urinary malondialdehyde + 4-hydroxyalkenals, and serum oxygen-radical absorbance capacity. RESULTS: The within-group mean changes (and 95% CIs) in urinary 8-iso-prostaglandin F(2alpha) (pg/mg creatinine) were 9.0 (-125.1, 143.1), -150.0 (-275.4, -24.6), -141.3 (-230.5, -52.1), and -112.5 (-234.8, 9.8) in the placebo, vitamin C alone, vitamin E alone, and vitamins C + E groups, respectively. No synergistic effect of these 2 vitamins on urinary 8-iso-prostaglandin F(2alpha) was observed (P = 0.12). Neither vitamin had an effect on urinary malondialdehyde + 4-hydroxyalkenals. Vitamin C, but not vitamin E, increased serum oxygen-radical absorbance capacity (P = 0.01). CONCLUSIONS: Supplementation with vitamin C or vitamin E alone reduced lipid peroxidation to a similar extent. Supplementation with a combination of vitamins C and E conferred no benefit beyond that of either vitamin alone.     

Vitamin C, vitamin E, and beta-carotene in relation to common cold incidence in male smokers.

We evaluated the role of dietary vitamin C, vitamin E, and beta-carotene, as well as long-term vitamin E and beta-carotene supplementation, on the incidence of common cold episodes. A cohort of 21,796 male smokers was drawn from the Alpha-Tocopherol Beta-Carotene Cancer Prevention Study, which examined the effects of 50 mg per day vitamin E and 20 mg per day beta-carotene on lung cancer. Diet and background characteristics were recorded at the study entry, and subjects were queried three times per year on common cold episodes. We modeled the total number of colds during a 4-year follow-up period with Poisson regression, adjusting for covariates of dietary intake. Dietary vitamins C and E and beta-carotene had no meaningful association with common cold incidence. Long-term vitamin E and beta-carotene supplementation had no overall effect.Among subjects 65 years of age or older, the incidence of colds was slightly lower in the vitamin E group (RR = 0.95; 95% CI = 0.90-1.00); this reduction was greatest among older city dwellers who smoked fewer than 15 cigarettes per day (RR = 0.72; 95% CI = 0.62-0.83). In this male smoking population, vitamins C and E and beta-carotene had no overall association with the incidence of common cold episodes.     

Effects of dietary vitamin E and high supplementation of vitamin C on plasma glucose and cholesterol levels

Weanling male Sprague Dawley rats were fed ad libitum a purified basal diet free of vitamins E and C. In Experiment I (4 weeks), 24 rats were divided into four groups with 2×2 factorial design. They were supplemented with 0 or 45 IU/kg diet of vitamin E, and O or 2.0 g/kg diet of vitamin C. In Experiment II (16 weeks), 36 rats were divided into six groups with 2×3 factorial design. Vitamin E was supplemented at the level of O or 45 IU/kg diet, and vitamin C was supplemented at the level of O, 1.5, or 3.0 g/kg diet, respectively. Plasma glucose level and cholesterol level were determined in both experiments. The plasma levels of glucose and cholesterol were significantly and negatively correlated. Plasma glucose level was significantly increased and plasma cholesterol level significantly decreased by the high supplementation of vitamin C with or without vitamin E in the diet. Vitamin E deficiency decreased plasma glucose level and increased plasma cholesterol level significantly with or without vitamin C supplementation. The groups with adequate level of vitamin E (45 IU/kg diet) and no vitamin C showed moderate plasma glucose and cholesterol levels.     

Lung function and blood levels of copper, selenium, vitamin C and vitamin E in the general population

BACKGROUND: Increased dietary intake of antioxidants has been associated with higher lung function, but few studies have used biological markers of antioxidant intake. OBJECTIVE: This study aimed to determine if antioxidant status, as measured by blood levels, influences lung function. DESIGN: Using a random subsample of 479 participants, aged 18-65 y old, from a larger cross-sectional observational study, the association of forced expiratory volume in 1 s (FEV1) with plasma copper, vitamin C, vitamin E and serum selenium was assessed. RESULTS: An s.d. increase in blood copper level was associated with a difference in FEV1 of -48 ml (95% confidence intervals: -95, -2 ml, P = 0.04), vitamin C +49 ml (+4, +94, P = 0.03), vitamin E -15 ml (-62, +32, P = 0.53) and selenium +52 ml (+7, +96, P = 0.02). The sizes of association were not appreciably altered in a mutually adjusted model. CONCLUSIONS: Higher levels of serum vitamin C and selenium appear to be associated with higher FEV1. The association between higher serum copper and lower FEV1 requires further study in view of the ubiquitous exposure to this mineral.     

沥青烟作业工人脂质过氧化水平的观察

目的 探讨沥青烟作业工人脂质过氧化水平和红细胞膜ATP酶活力的改变.方法 选择炭素分厂生阳极车间接触沥青烟工人53名为观察组,选择该厂非沥青烟作业职工50名为对照组,检测血浆中脂质过氧化水平相关指标谷胱甘肽过氧化物酶(GSH-Px)、一氧化氮合酶(NOS)、总超氧化物歧化酶(T-SOD)活力和丙二醛(MDA)、一氧化氮(NO)含量及总抗氧化能力(T-AOC)、抑制羟自由基能力和红细胞膜Na~+-K~+-ATPase和Ca~(2+)-ATPase活力.结果 观察组抑制羟自由基能力为(786.03±227.54)U/ml,与对照组[(897.79±153.87)U/ml)]比较明显降低,差异有统计学意义(P<0.05).观察组MDA含量为(11.97±4.26)nmol/ml,明显高于对照组[(9.26±4.90)nmol/ml)],差异有统计学意义(P<0.05).观察组红细胞膜Na~+-K~+-ATPase活力为(18.83±9.97)U/ml,明显低于对照组[(27.06±11.62)U/ml)],差异有统计学意义(P<0.05).抑制羟自由基能力、GSH-Px活力与工龄呈负相关(r=-0.320,r=-0.347,P<0.05),MDA含量与工龄呈正相关(r=0.421,P<0.01).红细胞膜Na~+-K~+-ATPase和Ca~(2+)-ATPase活力与工龄均无明显相关性.结论 沥青烟可引起作业工人脂质过氧化水平和红细胞膜ATP酶活力的改变     

Serum vitamin E levels in very low-birth weight infants receiving vitamin E in parenteral nutrition solutions

Serum vitamin E levels were measured in 17 very low-birth weight infants in the first 2 wk of life, before and after the institution of intravenous vitamin E supplementation in a dosage of 4.5 mg/day, as a component of MVI Pediatric multivitamin preparation. Serum vitamin E levels were 0.22 +/- 0.16 (SD) mg/dl before supplementation, and rose to 2.55 +/- 0.65 (SD) mg/dl in nine infants more than 899 g birth weight, and rose to 3.68 +/- 0.70 (SD) mg/dl in six infants less than 900 g at birth. These postsupplementation serum vitamin E levels are in the range in which a reduction of incidence or severity of retinopathy of prematurity and intraventricular cerebral hemorrhage has been reported by others. No toxic effects of the preparation or of the increased vitamin E levels were found.     

Vitamin E status of northern Canadian newborns: relation of vitamin E to blood lipids

Vitamin E status was determined in two groups of Canadian newborns: a northern group, mainly aboriginal (Indian and Inuit), and a southern group, mainly nonnative. Serum vitamin E, cholesterol, and triglyceride levels were measured in cord blood and ratios of vitamin E to both cholesterol (E:chol) and cholesterol plus triglyceride (E:chol + TG) were calculated. For the combined groups the mean serum concentration of vitamin E (8.71 +/- 2.45 mumol/L), cholesterol (1.77 +/- 0.46 mmol/L), and triglyceride (0.65 +/- 0.30 mmol/L) as well as the ratios E:chol (5.00 X 10(-3) +/- 1.26 X 10(-3) and E:chol + TG (3.60 X 10(-3) +/- 0.77 X 10(-3) were within normal limits. Significant north-south differences were found only in the mean triglyceride concentration, which was lower (p = 0.03), and E:chol + TG, which was higher (p = 0.002), in the northern than in the southern group. No differences attributable to differences in race were found. Only one infant, an Inuit in the northern group, was found to be deficient in vitamin E.     

Differential response of plasma and immune cell's vitamin E levels to physical activity and antioxidant vitamin supplementation

OBJECTIVE: To assess the differential response of plasma, lymphocyte and neutrophil vitamin E levels to high-intensity physical activity and to vitamin C and E supplementation. SUBJECTS: In all, 14 male trained amateur runners (32-36 y old) were randomly divided in two groups (supplemented and placebo), and participated in a half marathon race. The subjects did not take any other supplements than the ones provided for this study. INTERVENTION: Vitamin C (152 mg/day) and E (50 mg/day) supplementation was administrated to athletes for a month, using a new almond-based isotonic and energetic beverage (supplemented group). The usual dietary habits of participants were assessed using a self-reported 7-day 24-h recall before the day of the study. To avoid the beverage influence, nonenriched vitamin C and E almond-based isotonic and energetic beverage was given to the placebo group. After 1 month, subjects participated in a half marathon race (21 km run). Vitamin E concentration was determined in plasma, neutrophils and lymphocytes before and immediately after the race, and 3 h after finishing the race. RESULTS: Daily energy intake and caloric profile of supplemented and placebo group were not different except for vitamin C and E supplementation. Vitamin supplementation and exercise had no effect on vitamins E levels in plasma. The exercise significantly (P<0.05) increased the lymphocyte vitamin E concentration both in the placebo (+119%) and supplemented groups (+128%), and neutrophil vitamin E content in the supplemented group (+88%). These levels remained significantly (P<0.05) high after the short recovery. After exercise, vitamin E levels in lymphocytes and neutrophils of supplemented subjects were practically twice the levels before exercise, whereas neutrophil vitamin E content of the placebo group was close to those in plasma. CONCLUSION: After endurance exercise, lymphocytes increased their vitamin E content in the supplemented and placebo subjects whereas this trend in neutrophils was just observed in the supplemented group. The determination of vitamin E content in lymphocytes and neutrophils after exercise is a useful tool to assess the functional status of vitamin E.     

亚慢性染毒2,3,7,8-四氯二苯并二(噁)英(TCDD)对大鼠血清维生素A、E的影响

目的了解亚慢性暴露于2，3，7，8-四氯二苯并二噁英（TCDD）对Wistar大鼠血清维生素A、E水平的影响。方法将64只实验Wistar大鼠按雌、雄随机分为染毒高（250ng／kg）、中（25ng／ks）、低（2．5ng／kg）剂量和空白对照共4组，每组8只，经口染毒。90d后对实验大鼠股动脉取血，离心后取上层血清，用无水乙醇沉淀蛋白，加环己烷萃取后，使用荧光分光光度仪在不同波长下测定其荧光值，计算出维生素A、E浓度，进行统计分析。结果与对照组比较，TCDD染毒大鼠血清维生素A和维生素E的平均水平降低，差别具有统计学意义（P〈0．05）。结论在实验条件下，TCDD亚慢性暴露可以对Wistar大鼠血清维生素A与维生素E的质量浓度水平有一定影响。