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1.
S. elik
. Yilmaz T. Aan M. Nazirolu M. ay M. Aksakal 《Cell biochemistry and function》1999,17(2):115-121
In this study, the effects of dietary vitamin E, selenium, and their combination on the levels of fatty acid composition of the brain and liver tissues were examined. In brain tissue, the amounts of most fatty acids increased in vitamin E, combination and selenium groups compared with control group values. While the proportions of myristic, pentadecanoic, palmitic, linoleic, and total saturated fatty acids were decreased in vitamin E, Se and combination groups, eicosapentaenoic, total unsaturated and MUFA were increased in the same groups. In addition, the proportions arachidonic, eicosapentaenoic, total unsaturated, ω6 and MUFA in the combination group were higher than in the control group. In liver tissue, the amounts of myristic, pentadecanoic, palmitic, eicosedienoic, eicosapentaenoic, docosahexaenoic, ω3 and PUFA were higher in the combination group than in the control group. Also the proportions of eicosapentaenoic, docosahexaenoic acids in supplemented groups were higher than those in the control group. We conclude that dietary vitamin E and selenium have an influence on the levels of fatty acids in the brain and liver. Copyright © 1999 John Wiley & Sons, Ltd. 相似文献
2.
Experiments were conducted to determine whether the increased glutathione S-transferase (GSH-T) activity associated with selenium
(Se) deficiency is necessarily related to losses in the activity of Se-dependent glutathione peroxidase (SeGSHpx) in chicks.
Nutritional Se status was altered in two ways: by treatment with an antagonist of Se utilization, aurothioglucose (AuTG),
and by feeding diets containing excess Se. Chicks given AuTG (10–30 mg AU/kg, sc) had growth rates and hepatic GSH concentrations
that were comparable to those of saline-treated controls; however, their plasma GSH levels exceeded those of either Se-deficient
(6-fold) or-adequate (3-fold) saline-treated chicks. Hepatic SeGSHpx activities of AuTG-treated chicks were hals those of
controls under conditions of Se-adequacy; however, this effect was not detected when Se was deficient. Hepatic GSH-TCDNB (assayed with 1-chloro-2,4-dinitrobenzene) activities of AuTG-treated chicks were significantly greater than those of controls
when Se was deficient (i.e., when SeGSHpx activity was 12% of the Se-adequate level); however, deprivation of Se did not affect
GSH-TCDNB activity in the absence of AuTG. chicks fed excess Se (6–20 ppm as Na2SeO3) in diets containing either low (2 IU/kg) or adequate (100 IU/kg) VE, showed hepatic GSH-TCDNB activities and GSH concentrations greater than those of Se-adequate (0.2 ppm Se) chicks by 100% and 40%, respectively. That
increased hepatic GSH-TCDNB activity can occur because of either AuTG or excess Se status under conditions wherein SeGSHpx activity is not affected indicates
that the transferase response is not directly related to changes in the peroxidase. 相似文献
3.
The effect of vitamin B6 on the levels of tissue selenium (Se) and glutathione peroxidase (GSH-Px) was studied. Male Wistar 4-week-old rats were fed a vitamin B6-Se-deficient basal diet for 2 weeks, then divided into 10 groups of five or six rats and fed their respective diets for 4 weeks. The experimental design was a 2×2×2 factorial with two levels of vitamin B6, two forms of Se, and two levels of Se, plus two extra groups (vitamin B6-supplemented and deficient without Se). Vitamin B6 was 0 and 250 μg pyridoxine-HCl/100 g of diet; Se forms were Na2SeO3 and DL-selenomethionine; Se levels were 0.5 and 5.0 mg Se/kg of diet. Regardless of form or level of Se, vitamin B6-deficient rats had lower body weights and organ weights than vitamin B6-supplemented rats. At 5.0 mg Se/kg of diet, Na2SeO3 caused a further depression. Vitamin B6 deficiency resulted in a higher Se level and GSH-Px activity in plasma of rats fed selenomethionine. However, Se content an GSH-Px activity in erythrocytes were significantly elevated in vitamin B6-supplemented rats compared with vitamin B6-deficient rats. Se levels in muscle and heart were significantly lower in vitamin B6-deficient groups fed Na2SeO3 than in vitamin B6-supplemented groups. Vitamin B6-deficient rats fed selenomethionine had higher Se levels in muscle, heart, spleen, liver, and kidneys than vitamin B6-supplemented rats. Activity of GSH-Px in muscle, heart, and spleen was significantly lower in vitamin B6-deficient groups than in vitamin B6-supplemented groups, regardless of form of Se. A significant decrease of GSH-Px in liver was observed in vitamin B6-deficient rats fed selenomethionine compared with vitamin B6-supplemented rats, whereas no significant decrease was observed in those fed Na2SeO3. These results suggest that vitamin B6 is involved in the distribution and transportation of Se in body and the metabolism of selenomethionine in liver. 相似文献
4.
5.
Xin Gen Lei Deborah A. Ross John E. Parks Gerald F. Combs 《Biological trace element research》1997,59(1-3):195-206
Phospholipid hydroperoxide glutathione peroxidase (PHGPX) is the second intracellular selenium (Se)-dependent glutathione
peroxidase (GSH-Px) identified in mammals. Our objectives were to determine the effect of dietary vitamin E and Se levels
on PHGPX activity expression in testis, epididymis, and seminal vesicles of pubertal maturing rats, and the relationship of
PHGPX expression with testicular development and sperm quality. Forty Sprague-Dawley male weanling rats (21-d old), were initially
fed for 3 wk a torula yeast basal diet (containing 0.05 mg Se/kg) supplemented with marginal levels of Se (0.1 mg/kg as Na2SeO3) and vitamin E (25 IU/kg as all-rac-α-tocopheryl acetate). Then, rats were fed the basal diets supplemented with 0 or 0.2
mg Se/kg and 0 or 100 IU vitamin E/kg diet during the 3-wk period of pubertal maturing. Compared with the Se-supplemented
rats, those fed the Se-deficient diets retained 31, 88, 67, and 50% of Se-dependent GSH-Px activities in liver, testis, epididymis,
and seminal vesicles, respectively. Testes and seminal vesicles had substantially higher (5-to 20-fold) PHGPX activity than
liver. Dietary Se deficiency did not affect PHGPX activities in the reproductive tissues, but reduced PHGPX activity in liver
by 28% (P < 0.0001). Dietary vitamin E supplementation did not affect PHGPX activity in liver, whereas it raised PHGPX activity
in seminal vesicles by 43% (P < 0.005). Neither dietary vitamin E nor Se levels affected body weight gains, reproductive organ
weights, or sperm counts and morphology. In conclusion, expression of PHGPX activity in testis and seminal vesicles was high
and regulated by dietary Se and vitamin E differently from that in liver. 相似文献
6.
M. C. Santos H. Rodrigues S. Vasconcelos V. Andrade M. J. Lança A. M. Viegas Crespo 《Biological trace element research》1995,47(1-3):257-261
Two age groups, 3 and 15 mo, were used to investigate whether age-associated changes in some parameters related to lipid peroxidation
occur in the liver of male Wistar rats and to observe possible effects of dietary selenium supplementation (0.25 and 0.50
ppm) for 12 mo on the same parameters. At these experimental conditions, the most important observation was that peroxidation
did not change by aging, at least until 15 mo of age. In addition, the activity of Sedependent glutathione peroxidase (GSH-Px,
EC 1.11.1.9) was higher in the liver of the older animals. It is suggested that the enzyme could have a role in the unchanged
hepatic peroxidation observed in aged male rats. On the other hand, an effect of dietary selenium supplementation on those
parameters was not observed, probably because the selenium levels were still at an adequate plateau. 相似文献
7.
Peter Surai Inna Kostjuk Graham Wishart Allan Macpherson Brian Speake Raymond Noble Igor Ionov Evgeny Kutz 《Biological trace element research》1998,64(1-3):119-132
The phospholipids of avian spermatozoa are characterized by high proportions of arachidonic (20:4n-6) and docosatetraenoic
(22:4n-6) fatty acids and are therefore sensitive to lipid peroxidation. α-Tocopherol and glutathione peroxidase [GSH-Px]
are believed to be the primary components of the antioxidant system of the spermatozoa. The present study evaluates the effect
of vitamin E and vitamin E plus Se supplementation of the cockerel diet on GSH-Px activity, vitamin E accumulation, and lipid
peroxidation in the spermatozoa, testes, and liver. At the beginning of the experiment 75 Rhode Island Red cockerels were
divided into five groups, kept in individual cages, and fed a wheat-barley-based ration balanced in all nutrients. Supplements
fed to the different groups were as follows: vitamin E, 0, 20, 200, 20, and 200 mg/kg to groups 1–5, respectively, with groups
4 and 5 also receiving 0. 3 mg Se/kg. The vitamin E supplementation produced increased levels of α-tocopherol in semen, testes,
and liver. The inclusion of the Se into the cock diet had a significant (P < 0.01) stimulating effect on GSH-Px activity in
seminal plasma, spermatozoa, testes, and liver. The increased vitamin E concentration in the spermatozoa was associated with
a reduction in their susceptibility to lipid peroxidation. Similarly, the increased GSH-Px activity provided enhanced protection
against lipid peroxidation. 相似文献
8.
The aim of this work was to determine the effects of dietary intake vitamin E and selenium (Se) on lipid peroxidation as thiobarbituric
acid reactive substances (TBARS) and on the antioxidative defense mechanisms in the liver of rats treated with high doses
of prednisolone. Two hundred fifty adult male Wistar rats were randomly divided into five groups. The rats were fed a normal
diet, but groups 3, 4, and 5 received a daily supplement in their drinking water of 20 mg vitamin E, 0.3 mg Se, and a combination
of vitamin E and Se, respectively, for 30 d. For 3 d subsequently, the control group (group 1) was treated with a placebo,
and the remaining four groups were injected intramuscularly with 100 mg/kg body weight (BW) prednisolone. After the last administration
of prednisolone, 10 rats from each group were killed at 4, 8, 12, 24, and 48 h and the activities of glutathione peroxidase
(GSH-Px), superoxide dismutase (SOD), and catalase (CAT) enzymes and the levels of glutathione (GSH) and TBARS in their livers
were measured. GSH-Px, SOD, and CAT enzyme activities and GSH levels in prednisolone-treatment group (group 2) began to decrease
gradually at 4 h, falling respectively to 38%, 55%, and 40% of the control levels by 24 h, and recovering to the control levels
at 48 h. In contrast, prednisolone administration caused an increase in the hepatic TBARS, reaching up to four times the levels
of the control at 24 h. However, supplementation with vitamin E and Se had a preventive effect on the elevation of the hepatic
TBARS and improved the diminished activities of the antioxidative enzymes and the levels of GSH. Therefore, the present study
demonstrates the effectiveness of vitamin E and Se in reducing hepatic damage in glucocorticoid-treated rats and suggests
that reductions in increased TBARS as a result of prednisolone may be an important factor in the action of vitamin E and Se. 相似文献
9.
Abdurrahim Kocyigit Ozcan Erel Mehmet S. Gurel Senel Avci Necmeddim Aktepe 《Biological trace element research》1998,65(3):271-281
The aim of this study was to measure the alterations in serum selenium (Se), copper (Cu), zinc (Zn), and iron (Fe) concentrations
and their carrier proteins, ceruloplasmin (Cp), transferrin (Tf) albumin, and related antioxidant enzyme activities, erythrocyte
Cu-Zn Superoxide dismutase (Cu-Zn SOD), glutathione peroxidase (GSH-Px), and catalase (CAT) activities in patients with cutaneous
leishmaniasis (CL). Erythrocyte Cu-Zn SOD activities, serum Cu concentrations, and Cp levels were found to be significantly
higher in the patients group than those of controls. However, GSH-Px and CAT activities and Se, Zn, Fe, and Tf levels were
lower in patients than in the control subjects. There were positive important correlation’s between Cu-Zn SOD and Cp, Cu-Zn
SOD and Cu, Cp and Cu, GSH-Px and Se, and Fe and CAT in the patients group. Our results showed that serum essential trace
elements Se, Zn, Cu, and Fe concentrations and their related enzymes Cu-Zn SOD, GSH-Px, and CAT activities change in CL patients.
The changes may be a part of defense strategies of organism and are induced by the hormonelike substances. 相似文献
10.
Twenty-four weanling male Wistar rats were divided into four groups fed diets containing adequate or deficient levels of selenium
(0.5 ppm [+ Se] or <0.02 ppm [−Se] and protein (15% [+Pro] or 5% [−Pro]), but adequate levels of all other nutrients for 4
wk to determine the effects of Se deficiency and protein deficiency on tissue Se and glutathione peroxidase (GSHPx) activity
in rats. Plasma, heart, liver, and kidney Se and GSHPx were significantly lower in Se-deficient groups in relation to Se-sufficient
groups. In Se-deficient groups, Se and GSHPx were significantly higher in −Se−Pro rats in heart, liver, and kidney. Data analysis
showed that there were significant interaction effects between dietary Se and protein on Se and GSHPx of rats. It is assumed
that under the condition of Se deficiency. a low level of protein may decrease Se and GSHPx utilization, increase GSHPx synthesis,
and result in Se redistribution. This could account for high levels of Se and GSHPx in the −Se−Pro rats compared to −Se+Pro
rats. 相似文献
11.
The effects of dietary intake of vitamin E and selenium on arginase activity in the liver, kidneys, and heart of rats treated with high doses of prednisolone were investigated. Rats were divided into five groups. Groups 3, 4, and 5 received a daily supplement in their drinking water of vitamin E, Se, and a combination of vitamin E and Se, respectively, for 30 days. For 3 days subsequently, the control group (group 1) was given a placebo, and the remaining four groups were injected intramuscularly with prednisolone. The tissue samples were collected from each group at 4, 8, 12, 24, and 48 h after the last administration of prednisolone. In the group treated with prednisolone alone, arginase activity in the liver was found to have increased at all the time periods, whereas it had decreased significantly in the heart at 48 h. Arginase activity in the kidneys was not affected by prednisolone. Compared to the control and prednisolone groups, arginase activity in the kidneys and heart of the vitamin E- and Se-supplemented groups was found to be significantly increased at all time periods, however, no difference was seen in the combination group. Arginase activity in the liver of the vitamin E-supplemented group was found to have decreased at all time periods, however, in the Se group compared to the prednisolone group it had reduced at 24 and 48 h only. In the combination group compared to the prednisolone group, liver arginase activity increased constantly up to 12 h returning to normal values at 48 h. Vitamin E and Se in combination may prevent the changes in arginase activity in various tissues caused by prednisolone. 相似文献
12.
This study was conducted to determine the effects of vitamin E and selenium (Se) on lipid peroxidation (MDA), serum and liver
concentration of antioxidant vitamins, and some minerals of Japanese quails reared under heat stress (34°C). One hundred twenty
10-d-old Japanese qualis (60 males, 60 females) were randomly assigned to 4 treatment groups, 3 replicates of 10 birds each.
The experiment was designed in a 2×2 factorial arrangement using two levels of vitamin E (125 and 250 mg/kg of diet) and two
levels of selenium (0.1 and 0.2 mg/kg of diet). Greater dietary vitamin E and selenium inclusions resulted in a greater (p=0.001) serum vitamin E and vitamin A, but lower (p=0.001) MDA concentrations. Liver vitamin E and vitamin A concentrations increased (p=0.001) and MDA concentrations decreased (p=0.001) when both dietary vitamin E and selenium increased. No interactions between vitamin E and selenium were detected (p≥0.11) for any parameters. Increasing both dietary vitamin E and selenium caused an increase in serum concentrations of Fe
and Zn (p=0.001), but a decrease in serum concentration of Cu (p=0.001). Results of the present study showed that dietary vitamin E and selenium have synergistic effects and that supplementing
a combination of dietary vitamin E (250 mg/kg of diet) and selenium (0.2 mg/kg of diet) offers a good management practice
to reduce heat stress-related depression in performance of Japanese quails. 相似文献
13.
K. Charalabopoulos S. Karkabounas A. K. Charalabopoulos V. Papalimneou E. Ioachim X. Giannakopoulos 《Biological trace element research》2003,93(1-3):201-211
The reduction on peroxidation caused by benzopyrenes by some naturally occurring antineoplastic agents was studied in this
experimental work. Inhibition/reduction of experimental carcinogenesis induced by benzo(a)pyrene by vitamin C alone and by vitamin C/vitamin E and selenium/glutathione was attempted in 224 female Wistar rats divided
in four groups. Injected with 10.08 mL benzo(a)pyrene, the animals were treated with some naturally occurring substances like vitamin C alone and a combination of anticarcinogens.
By calculating the carcinogenic potency of benzo(a)pyrene and the anticarcinogenic potency of substances used as well as histological examination of developed tumors and survival
time of treated animals, it was found that vitamin C exerts a significant anticarcinogenic effect of 8.3 units and that the
combination of the two anticarcinogens used produced a significant prolongation of the animals survival time with anticarcinogenic
potency of 22.1 and 22.2 units, respectively. This is considered a potent anticarcinogenic effect. The question of an additional
supportive administration of such agents complementary to the conventional cancer chemotherapy in humans is raised. Of course,
further studies are needed. 相似文献
14.
选用200羽14日龄健康AA肉鸡,以电子自旋共振(ESR)捕集法和生物化学法对肉仔鸡血液和组织器官的不同自由基进行直接或间接测定,探讨VE和Se对肉鸡不同自由基代谢的作用及其动态变化.结果表明:组织一氧化氮(NO)自由基水平随日粮VE含量升高而降低,二者呈负相关关系,日粮高水平Se有诱导产生NO自由基的倾向;高VE和Se日粮显著提高血清和肝脏中SOD和GSH-Px的活性,但随处理时间的延长,组织SOD活性逐渐降低,而GSH-Px活性逐渐升高,说明日粮VE和/或Se不足均会诱导机体产生O.2-、H2O2自由基,且O2.-自由基会持续大量产生,而H2O2自由基仅在缺乏初期大量产生,而后趋于缓和;低VE和/或低Se均显著提高组织MDA含量,且低Se比低VE更为显著.VE和Se对肉鸡NO、O.2-和H2O2自由基代谢的作用存在协同效应. 相似文献
15.
Andreas S. Müller Josef Pallauf 《Journal of trace elements in medicine and biology》2003,17(3):183-192
Primary rabbit hepatocytes from 6 week old female New Zealand White rabbits (3.0 x 10(6) viable hepatocytes per treatment) were incubated for 24 h or 48 h with two basic variants of the selenium and vitamin E free DMEM/F12-HAM nutrition medium containing 2.5% or 10% fetal calf serum (FCS). Selenium and vitamin E concentrations of the media were varied by the addition of 0, 10, 50 and 100 ng Se/mL medium as sodium selenite and 100 microg alpha-tocopheryl acetate/mL. Lactic dehydrogenase (LDH) leakage of the hepatocytes was not influenced by the various selenium concentrations of the media, whereas vitamin E addition significantly inhibited LDH release. The activity of cellular glutathione peroxidase (GPx1) was markedly induced by increasing the selenium supplementation of the culture media. Vitamin E supply further enhanced GPx1 induction. In hepatocytes cultivated at the lower serum concentration (2.5% FCS), increasing the selenite concentration of the media raised GPx1 and reduced the intracellular levels of the reduced tripeptide glutathione (GSH). No vectored relation between the selenium concentration of the media and the activity of superoxide dismutase (SOD) could be observed. After both incubation periods (24 h and 48 h) SOD activity was significantly higher in the cytosol of hepatocytes grown in media containing 10% FCS as compared to cells incubated at the 2.5% FCS level. Furthermore, SOD activity was reduced by the addition of vitamin E to the media. In conclusion the results indicate an effective metabolism of rabbit hepatocytes for selenite even in amounts as low as nanograms. A general cytoprotective role for vitamin E can be shown by its ability to decrease LDH leakage and by the reduction of SOD activity. 相似文献
16.
Exposure of cells to ionizing radiation leads to the formation of reactive oxygen species (ROS) that are associated with radiation-induced
cytotoxicity. Because of the serious damaging potential of ROS, cells depend on the elaboration of the antioxidant defense
system (AODS), both enzymatic and nonenzymatic oxidant defense mechanisms. The deficiency in important components of the endogenous
AODS leads to the accumulation of oxidative stress inducing oxidative damage. The antioxidant enzymes superoxide dismutase
and glutathione peroxidase are key intracellular antioxidants in the metabolism of ROS.
In the current study, we investigated the potential role of these antioxidant enzymes in radioresistance during the evaluation
of the compensatory role of some exogenous micronutrients against oxidative stress
Animals were categorized into eight groups, receiving vitamin E (α-tocopherol) and/or selenium (Se) with or without whole-body
γ-irradiation (6.5 Gy).
The results indicate that antioxidant pretreatments before irradiation may have some beneficial effects against irradiation-induced
injury. The results also indicate that selenium and vitamin E act alone and in an additive fashion as radioprotecting agents.
The results further suggest that selenium confers protection in part by inducing or activating cellular free-radical scavenging
systems and by enhancing peroxide breakdown, whereas vitamin E appears to confer its protection by an alternate complementary
mechanism. 相似文献
17.
Monocrotaline (MCT) is a hepatotoxic pyrrolizidine alkaloid that is derived from plants; exposure may occur by consumption of contaminated grains, herbal teas and medicines. MCT can cause liver damage. We investigated the antioxidant effects of selenium (Se) and vitamin E against the toxic effects of MCT. Female Wistar albino rats were divided into four groups: a control group, an MCT group, an MCT + Se group, and an MCT + vitamin E group. Liver tissues were harvested, fixed, processed to paraffin and sections were cut. Anti-von Willebrand factor (vWF) immunohistochemistry, terminal deoxynucleotidyl transferase dUTP nick end-labeling (TUNEL), and hematoxylin and eosin staining were performed. Serum and liver tissue glutathione (GSH), catalase (CAT), and glutathione peroxidase (GPx) levels were measured. Histopathological and TUNEL data showed significantly increased liver damage in the MCT group compared to controls. Histopathological and TUNEL staining indicated significant improvements in the MCT + vitamin E and MCT + Se groups compared to the MCT group. MCT significantly reduced the serum GSH level and GPx activity, and liver GPx activity. Biochemical data indicated a significant improvement in serum GSH level in the MCT + vitamin E group compared to the MCT group. We suggest that vitamin E and Se afford limited protection against MCT hepatotoxicity. 相似文献
18.
《Animal : an international journal of animal bioscience》2013,7(4):562-570
The objective of this study was to determine the concentration of total selenium (Se) and the proportions of total Se comprised as selenomethionine (SeMet) and selenocysteine (SeCys) in the postmortem tissues of female pheasants (Phasianus Colchicus Torquator) offered diets that contained graded additions of selenised-enriched yeast (SY) or a single comparative dose of sodium selenite (SS). Thiobarbituric acid reactive substances (TBARS) and tissue glutathione peroxidase (GSH-Px) activity of breast (Pectoralis Major) were assessed at 0 and 5 days postmortem. A total of 216 female pheasant chicks were enrolled into the study. Twenty-four birds were euthanased at the start of the study, and samples of blood, breast muscle, leg muscle (M. Peroneus Longus and M. Gastrocnemius), heart, liver, kidney and gizzard were collected for determination of total Se. Remaining birds were blocked by live weight and randomly allocated to one of four dietary treatments (n = 48 birds/treatment) that either differed in Se source (SY v. SS) or dose (control (0.17 mg total Se/kg), SY-L and SS-L (0.3 mg/kg total Se as SY and SS, respectively) and SY-H (0.45 mg total Se/kg)). Following 42 and 91 days of treatment, 24 birds per treatment were euthanased, and samples of blood, breast muscle, leg muscle, heart, liver, kidney and gizzard were retained for determination of total Se and the proportion of total Se comprised as SeMet or SeCys. Whole blood GSH-Px activity was determined at each time point. Tissue GSH-Px activity and TBARS were determined in breast tissue at the end of the study. There were increases in both blood and tissues to the graded addition of SY to the diet (P < 0.001), but the same responses were not apparent with the blood and tissues of selenite-supplemented birds receiving a comparable dose (SY-L v. SS-L). Although there were differences between tissue types in the distribution of SeMet and SeCys, there were few differences between treatments. There were effects of treatment on erythrocyte GSH-Px activity (P = 0.012) with values being higher in treatments SY-H and SS-L when compared with the negative control and treatment SY-L. There were no effects of treatment on tissue GSH-Px activity, which is reflected in the overall lack of any treatment effects on TBARS. 相似文献
19.
Effect of physical restraint on oxidative stress in mice fed a selenium and vitamin E deficient diet
Physical restraint has been associated with increased oxidative damage to lipid, protein, and DNA. The purpose of this experiment
was to determine whether physical restraint would further exacerbate oxidative stress in mice fed a selenium (Se) and vitamin
E (VE) deficient diet. Three-week-old mice were fed a Torula yeast diet containing adequate or deficient Se and VE. Menhaden
oil was added to the deficient diet to impose an additional oxidative stress. After 4 wk feeding, half the mice in each group
were restrained for 5 d in well-ventilated conical tubes for 8 h daily. Mice fed the Se and VE deficient diets had increased
liver thiobarbituric acid-reactive substance (TBARS) levels and decreased liver glutathione peroxidase (GPX1) activity and
α-tocopherol levels. Plasma corticosterone levels were elevated in restrained mice fed the deficient diet compared to unrestrained
mice fed the adequate diet. Restraint had no effect on liver TBARS or α-tocopherol levels. Liver GPX1 activity, however, was
lower in restrained mice fed the adequate diet. In addition, liver superoxide dismutase (SOD) activity was lower in the restrained
mice fed the adequate or deficient diet. Thus, under our conditions, Se and VE deficient diet, but not restraint, increased
lipid peroxidation in mice. Restraint, however, decreased antioxidant protection in mice due to decreased activities of GPX1
and SOD enzymes. 相似文献
20.
Modulation of the platelet thromboxane A2 and aortic prostacyclin synthesis by dietary selenium and vitamin E 总被引:1,自引:0,他引:1
Mohsen Meydani 《Biological trace element research》1992,33(1-3):79-86
Vitamin E and selenium (Se) interact synergistically as an important antioxidant defense mechanism. Se, an essential component
of glutathione peroxidase (GSH-Px) and vitamin E decompose fatty acid hydroperoxides and hydrogen peroxides generated by free
radical reactions. Vitamin E and GSH-Px may modulate arachidonic acid metabolism and the activity of cyclooxygenase enzymes
by affecting peroxide concentration. The balance between arterial wall prostacyclin (PGI2) production and platelet thromboxane (TX)A2 directly influences platelet activity. In order to elucidate the differential role of dietary vitamin E and Se in aortic
PGI2 and platelet TXA2 synthesis, 1-mo-old F344 rats were fed semipurified diets containing different levels of vitamin E (0, 30, 200 ppm) and Se
(0, 0.1, 0.2 ppm) for 2 mo. Thromboxane B2 (TXB2) and 6-keto-PGF1α, were measured by radioimmunoassay (RIA) after incubation of whole blood and aortic rings at 37°C for 10 and 30 min, respectively.
Vitamin E deficiency reduced plasma vitamin E to 5–17% of control-fed rats, and supplementation increased it to 53% of the
control-fed rats. Se supplementation in vitamin E-supplemented animals increased plasma GSH-Px by 17%, compared to vitamin
E-deficient rats. Se and vitamin E supplementation did not have a similar effect on TXB2 and PGI2 synthesis. Se deficiency did not alter platelet TXB2 synthesis, but significantly decreased aortic PGI2 synthesis. It was necessary to supplement with both antioxidants in order to increase, PGI2 synthesis. Se and vitamin E deficient groups had a higher TXB2/PGI2 ratio (0.17±0.08) compared to Se- and vitamin E-supplemented groups (0.03±0.01). These results confirm previous reports in
humans and animals and are in accordance with epidemiological data indicating an inverse relationship between plasma Se and
platelet aggregation. Thus, further suggesting that vitamin E and Se may have a specific role in controlling TXA2 and PGI2 synthesis. 相似文献