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Tocopherol Levels (tocopherol + level)
Selected Abstracts,-tocopherol, an exogenous factor of adult hippocampal neurogenesis regulationJOURNAL OF NEUROSCIENCE RESEARCH, Issue 4 2003Tiziana Cecchini Abstract In previous work, we found that adult hippocampal neurogenesis in rat is affected by vitamin E deficiency. Because vitamin E deficiency is a complex condition involving numerous biological systems, it is possible that its effect on postnatal new neuron production could be mediated by unknown changes in different factors that in turn play a role in this process. To clarify if vitamin E plays a direct role in regulating hippocampal neurogenesis, we studied the neurogenesis in adult control rats and in adult rats under supplementation with ,-tocopherol, the most important compound of vitamin E. The ,-tocopherol level in control and supplemented rats was monitored. Qualitative and quantitative analysis of cell proliferation and death was carried out and expression of immature neuron markers PSA-NCAM, TUC 4, and DCX was investigated in hippocampus dentate gyrus. ,-Tocopherol levels increased significantly in both plasma and brain after supplementation. Cell proliferation was inhibited in ,-tocopherol-supplemented rats, the number of dying cells was reduced, and the number of cells expressing the immature neuron markers was increased. The results obtained confirm and extend the idea that vitamin E is an exogenous factor playing a direct role in regulation of different steps of adult hippocampal neurogenesis. Some hypotheses about the possible mechanisms underlying the complex action of ,-tocopherol, related to its antioxidant and molecule-specific non-antioxidant properties, are proposed and discussed. © 2003 Wiley-Liss, Inc. [source] Effects of different dietary phytase activities on the concentration of antioxidants in the liver of growing broilersJOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 4 2010F. Karadas Summary One-hundred and fifty male chickens were used to evaluate the effects of different activities (0, 250, 500, 12 500 FTU/kg) of phytase on their performance and antioxidant concentration in the liver. The chicks were housed in 30 cages and were allocated to six replicates of five dietary treatments. All diets were formulated to be adequate in energy and protein (12.90 MJ/kg metabolizable energy, 214 g/kg crude protein), however, the negative control (NC) was lower in available P compared with the positive control (PC) (2.5 vs. 4.5 g/kg diet). The other three diets were the NC supplemented with phytase at 250, 500 and 12 500 FTU/kg (NC + 250, NC + 500 and NC + 12 500 FTU respectively). The concentration of antioxidants in the liver of the birds was determined using HPLC at 21 days of age. Low P diets (NC) reduced weight gain, however, supplementation with phytase improved weight gain to the extent that it was better than the PC at the 12 500 FTU treatment (p < 0.05). Feed conversion ratio was also improved by the high level of phytase supplement more than other treatments (p < 0.05). Feed consumption was not affected either by dietary phosphorus concentration or by different phytase supplementation. The antioxidant data showed that the unsupplemented diet with low phosphorus (NC) decreased the concentration of coenzyme Q10 and retinol-linoleate in the liver compared with that of birds on the adequate phosphorus treatment (PC). Phytase supplementation, especially at the higher doses (500 and 12 500 FTU) increased the level of coenzyme Q10 to the same level as the PC treatment. In addition, the highest dose (12 500 FTU) of phytase increased retinol concentration in the liver of chickens compared with those on the NC treatment. The highest inclusion level of phytase increased the ,-tocopherol level in the liver compared with the lower levels of phytase (NC + 250 and NC + 500 FTU). [source] FACTORS AFFECTING LIPID OXIDATION IN BREAST AND THIGH MUSCLE FROM CHICKEN, TURKEY AND DUCKJOURNAL OF FOOD BIOCHEMISTRY, Issue 4 2010Y. GONG ABSTRACT Lipid oxidation occurred rapidly in turkey muscle, intermediate in duck and slowest in chicken. pH was lowest in turkey muscle. Chicken muscle had a lower content of polyunsaturated fatty acids compared with turkey and duck muscles. The aqueous fraction of duck breast inhibited hemoglobin-mediated lipid oxidation in washed muscle more effectively than aqueous fractions from turkey and chicken muscle. ,-Tocopherol content was highest in duck muscle, intermediate in chicken and lowest in turkey. Depletion of tocopherols during frozen storage was more rapid in turkey and duck compared with chicken. It was thought that the elevated tocopherol level in chicken muscle may be caused by less efficient catabolism via the omega hydroxylation pathway. However, tocopherol hydroxylase activity was similar in chicken compared with turkey liver microsomes. Heme pigment content was around sixfold higher in duck breast compared with chicken and turkey breast. Duck thigh had especially elevated pH. PRACTICAL APPLICATIONS This work describes a number of factors that explain the wide variation in oxidative stability (chicken > duck > turkey) when comparing muscle tissues from the three avian species. These factors include muscle pH, concentration of heme pigments, fatty acid unsaturation, inhibitors of lipid oxidation in the aqueous fraction of the muscle, tocopherol content in lipid phases and depletion rates of tocopherol. These factors should be considered when developing strategies to inhibit lipid oxidation in muscle foods. The relatively high content of ,-tocopherol in chicken muscle compared with turkey should be a subject of further research to better understand the mechanisms by which certain animal species preferentially deposit the molecule into muscle. [source] ,-tocopherol, an exogenous factor of adult hippocampal neurogenesis regulationJOURNAL OF NEUROSCIENCE RESEARCH, Issue 4 2003Tiziana Cecchini Abstract In previous work, we found that adult hippocampal neurogenesis in rat is affected by vitamin E deficiency. Because vitamin E deficiency is a complex condition involving numerous biological systems, it is possible that its effect on postnatal new neuron production could be mediated by unknown changes in different factors that in turn play a role in this process. To clarify if vitamin E plays a direct role in regulating hippocampal neurogenesis, we studied the neurogenesis in adult control rats and in adult rats under supplementation with ,-tocopherol, the most important compound of vitamin E. The ,-tocopherol level in control and supplemented rats was monitored. Qualitative and quantitative analysis of cell proliferation and death was carried out and expression of immature neuron markers PSA-NCAM, TUC 4, and DCX was investigated in hippocampus dentate gyrus. ,-Tocopherol levels increased significantly in both plasma and brain after supplementation. Cell proliferation was inhibited in ,-tocopherol-supplemented rats, the number of dying cells was reduced, and the number of cells expressing the immature neuron markers was increased. The results obtained confirm and extend the idea that vitamin E is an exogenous factor playing a direct role in regulation of different steps of adult hippocampal neurogenesis. Some hypotheses about the possible mechanisms underlying the complex action of ,-tocopherol, related to its antioxidant and molecule-specific non-antioxidant properties, are proposed and discussed. © 2003 Wiley-Liss, Inc. [source] Plasma , -tocopherol level in diabetes mellitusBIOFACTORS, Issue 1-2 2000Hiroshi Tamai No abstract is available for this article. [source] Dietary supplementation of ,-tocopheryl acetate on ,-tocopherol levels in duck tissues and its influence on meat storage stabilityINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 3 2004Elizabeth Anne Russell Summary The effect of feeding three levels of ,-tocopheryl acetate on quality and stability of duck meat was studied. Day-old white Peking ducklings (n = 75) were assigned to three dietary treatments (n = 25) 20 mg , -tocopheryl acetate per kg feed (E20, control), 400 mg , -tocopheryl acetate per kg feed (E400) and 1000 mg , -tocopheryl acetate per kg feed (E1000). , -Tocopherol concentrations in breast, thigh, liver and heart tissues were significantly (P < 0.05) increased, in a dose-dependent manner. Supplementation also enhanced oxidative stability of duck muscle. Breast muscle was more susceptible to lipid oxidation than thigh muscle for all groups studied, even though breast muscle contained higher , -tocopherol levels than thigh muscle. These findings are significant because previous studies using chickens and turkeys showed that breast meat was always more stable than thigh meat and that thigh meat always had higher , -tocopherol levels than breast meat. Supplementation with , -tocopheryl acetate did not improve the colour stability of duck meat. [source] Effect of dietary oregano oil and , -tocopheryl acetate supplementation on iron-induced lipid oxidation of turkey breast, thigh, liver and heart tissuesJOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 9-10 2003G. Papageorgiou Summary Twenty-five 12-week-old turkeys randomly divided into five groups were given a basal diet, or a basal diet supplemented with 200 mg , -tocopheryl acetate/kg, or 100 mg oregano oil/kg or 200 mg oregano oil/kg, or 100 mg oregano oil plus 100 mg , -tocopheryl acetate/kg diet, for 4 weeks prior to slaughter. Breast, thigh, liver and heart tissues were subjected to iron-induced lipid oxidation, the extent of which was determined by third-order derivative spectrophotometry. Results showed that dietary oregano oil at the inclusion level of 200 mg oregano oil/kg diet was more effective in delaying lipid oxidation compared with the inclusion level of 100 mg/kg, but equivalent to the inclusion of 200 mg , -tocopheryl acetate/kg diet, which in turn was inferior to the combined inclusion of 100 mg oregano oil plus 100 mg , -tocopheryl acetate/kg, which was superior to all dietary treatments. Thigh tissue was more susceptible to oxidation than breast tissue, although it contained , -tocopherol at higher concentrations. Also, lipid oxidation in heart was relatively high, although it contained the highest , -tocopherol levels. This indicates that tissue , -tocopherol is one important factor influencing the level of lipid oxidation, but the distribution of lipids, iron and oregano oil in tissues must also be taken into consideration. Tissue , -tocopherol levels responded to dietary intake of 30,200 mg , -tocopheryl acetate/kg in the order heart > liver > thigh > breast. Breast, thigh and heart tissues from the oregano groups presented significantly (p < 0.05) higher levels of , -tocopherol compared with the control, the increase being positively correlated with the supplementation level. The increased levels of , -tocopherol in these tissues indicated that the dietary oregano oil exerted a protective action on , -tocopherol. [source] Dose-response efficacy of caraway (Carum carvi L.) on tissue lipid peroxidation and antioxidant profile in rat colon carcinogenesisJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 8 2006Muthaiyan Kamaleeswari Colon cancer is a leading cause of cancer death and its prevention is of great interest throughout the world. This study was conducted to examine the efficacy of different doses of dietary caraway (Carum carvi L.) on tissue lipid peroxidation (LPO) and antioxidant profile in rat colon carcinogenesis. Wistar male rats were divided into 6 groups and were fed a modified pellet diet for the whole of 30 weeks. To induce colon cancer, rats were given a weekly subcutaneous injection of 1,2-dimethylhydrazine (DMH) at a dose of 20 mg kg,1 (based on body weight) for the first 15 weeks. Caraway was supplemented every day orally at doses of 30, 60 and 90 mg kg,1 for different groups of rats for the total period of 30 weeks. All rats were sacrificed at the end of 30 weeks, the colons were examined visually for masses and were subsequently evaluated histologically. The results showed diminished levels of intestinal, colonic and caecal LPO products, such as conjugated dienes (CD), lipid hydroperoxides (LOOH) and thiobarbituric acid reactive substances (TBARS) and also the antioxidants superoxide dismutase (SOD), catalase (CAT), reduced glutathione (GSH) and glutathione reductase (GR) in DMH treated rats, which were significantly reversed (P < 0.05) on caraway supplementation. Moreover, enhanced activity of intestinal, colonic and caecal glutathione peroxidase (GPx), glutathione S-transferase (GST) and colonic ascorbic acid and ,-tocopherol levels were observed in carcinogen-treated rats, which were significantly (P < 0.05) reduced on caraway supplementation. Thus, our study showed that caraway supplementation at a dose of 60 mg kg,1 had a modulatory role on tissue LPO, antioxidant profile and prevented DMH-induced histopathological lesions in colon cancer rats. [source] A survey of sesamin and composition of tocopherol variability from seeds of eleven diverse sesame (Sesamum indicum L.) genotypes using HPLC-PAD-ECDPHYTOCHEMICAL ANALYSIS, Issue 4 2008Kelly S. Williamson Abstract The objective of this study was to determine the composition and content of sesamin and desmethyl tocopherols such as , -tocopherol (,T), , -tocopherol (,T) and , -tocopherol (,T) in seeds of sesame (Sesamum indicum L.) for 11 genotypes conserved in the United States Department of Agriculture (USDA), Agricultural Research Service (ARS) and Plant Genetic Resources Conservation Unit (PGRCU) in Griffin, Georgia, USA. Seed accessions studied were collections from eight countries worldwide, including one landrace from Thailand and two cultivars from Texas, USA. Novel methodologies and analytical techniques described herein consisted of reverse-phase high-performance liquid chromatography (HPLC) connected in series with two detection systems specific for each analyte class. Photodiode array detection was employed for sesamin analysis and electrochemical array detection was used in the determination of tocopherols. A preliminary study was conducted to assess sesamin levels in 2003 and tocopherol levels in 2004 from sesame seed samples conserved at the USDA, ARS and PGRCU. In 2005, sesame seed samples were grown, harvested and evaluated for sesamin as well as tocopherol levels. The overall results (n = 3) showed that sesamin, ,T, ,T and ,T levels were 0.67,6.35 mg/g, 0.034,0.175 µg/g, 0.44,3.05 µg/g and 56.9,99.3 µg/g respectively, indicating that the sesame seed accessions contained higher levels of sesamin and ,T compared with ,T and ,T. Statistical analysis was conducted and significant differences were observed among the 11 different sesame genotypes. This suggests that genetic, environmental and geographical factors influence sesamin and desmethyl tocopherol content. Copyright © 2007 John Wiley & Sons, Ltd. [source] Influence of Lactation History on Breast Nipple Aspirate Fluid Yields and Fluid CompositionTHE BREAST JOURNAL, Issue 2 2005Zora Djuric PhD Abstract: Analysis of nipple aspirate fluid (NAF) can be useful for understanding the impact that various lifestyle factors have on the biology of the breast. In this study, breast NAF was obtained at baseline from premenopausal women who volunteered for a dietary intervention trial. The influence of lactation history on both fluid yields and fluid composition was explored. We examined the levels of fat-soluble micronutrients (tocopherols, carotenoids, retinol), one lipid oxidation product (8-isoprostane), cholesterol, and protein in NAF. Roughly half of the women in the trial had never lactated, but this did not affect fluid yields appreciably. Carotenoid and tocopherol levels were significantly higher in NAF from women who lactated 6 months or more versus women who had lactated for shorter periods of time or never, but 8-isoprostane, protein, and cholesterol levels were not affected appreciably by lifetime lactation history. Longer times after weaning were associated with higher cholesterol levels, and there also was a suggestion the fat-soluble micronutrients declined with time after weaning. This is of interest since high cholesterol levels in breast fluid have been associated with an increased breast cancer risk, while carotenoids and tocopherols are thought to be protective. The results of this study provide further evidence of the potential benefits of prolonged lactation via its influence on NAF composition., [source] Effects of dietary vitamin E supplementation on growth performance, lipid peroxidation and tissue fatty acid composition of black sea bream (Acanthopagrus schlegeli) fed oxidized fish oilAQUACULTURE NUTRITION, Issue 3 2009S. PENG Abstract A 9-week feeding experiment was conducted to evaluate the effects of dietary vitamin E supplementation on growth, lipid peroxidation and fatty acid composition of black sea bream fed oxidized oil. The FL and OL diets contained fresh fish oil and oxidized oil, respectively, without additional vitamin E supplementation. Another four ,-tocopherol levels (150, 250, 450 and 800 mg kg,1 diet) were used within the OL diet, giving a total of six experimental diets. Fish were hand-fed to apparent satiation twice daily. At end of the trial, the weight gain and survival rate of fish were significantly reduced by diets with oxidized oil, whereas hepatosomatic index was remarkably high in fish fed oxidized oil diet. However, vitamin E supplementation to diet significantly improved growth performance and increased vitamin E content in the liver. Although, liver thiobarbituric acid reactive substances and docosahexaenoic acid were significantly increased by dietary oxidized oil, their levels were reduced by dietary vitamin E supplementation. Our results indicate that the fish were performing the best at intermediate concentrations of ,-tocopherol and a dose of >150 mg ,-tocopherol kg,1 diet could reduce lipid peroxidation and improve fish growth performance when oxidized oils exist in diet. [source] High remnant lipoprotein levels in patients with variant anginaCLINICAL CARDIOLOGY, Issue 6 2004Kunihisa Miwa M.D. Doctor-in-Chief Abstract Background: Dyslipidemia with increased oxidative stress but without elevation of low-density lipoprotein cholesterol has been recently implicated in the pathogenesis of coronary vasospasm. Hypothesis: Disordered triglyceride-rich lipoprotein metabolism may be linked to the genesis of coronary artery spasm. Methods: Both serum remnant lipoprotein (RLP) and ,-tocopherol levels were determined in 18 patients with the active stage of variant angina (VA), in 16 patients with the inactive stage of variant angina (IVA), and in 19 control subjects (CONTROL). Results: The RLP levels were significantly (p < 0.05) higher in VA (6.4 ± 2.7 mg/dl) than in IVA (4.4 ± 1.5 mg/dl). In contrast, ,-tocopherol levels were significantly lower in VA than that in CONTROL. Serum trigyceride levels were not significantly different among the study groups, although serum high-density lipoprotein cholesterol levels were significantly lower in VA than in CONTROL. Smoking was significantly (p < 0.05) more prevalent in VA (72%) than in IVA (25%) and CONTROL (37%). Serum RLP levels correlated positively with triglyceride levels (R = 0.73) and correlated inversely with ,-tocopherol levels (R = - 0.31) significantly in all study subjects. Conclusions: Patients with active stage of variant angina had higher RLP levels than inactive patients with variant angina and lower ,-tocopherol levels than control subjects. Disordered triglyceride-rich lipoprotein metabolism with increased oxidative stress appears to be linked to the activity of coronary vasospasm, suggesting a possible role in its pathogenesis. [source] | ||||||||||||||||