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Maternal reproductive health: Expression patterns of antioxidant enzyme selenoproteins of post-implantation embryos conceived by ethanol-treated murine mothers supplemented with α-tocopherol

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Asian pacific Journal of Reproduction 2017年第1期6卷 21-25页

作者： Gliceria B Ramos Noel F Alfonso Glenn G Oyong Aleli Jillian L Sia Biology Department De La Salle UniversityTaft AvenueManilaPhilippines1004 University Science Foundation-University Research Coordination Office (USF-URCO)De La Salle UniversityManilaPhilippines Molecular Biology Unit CENSERDe La Salle UniversityTaft AvenueManilaPhilippines Department of Biology College of Arts and SciencesUniversity of the Philippines-Manila

Objective:To investigate if the protective effect ofα-tocopherol against the impact of ethanol on brain morphogenesis involved the activity of the selenoproteins phospholipid hydroperoxide glutathione peroxidase (PHGPx;GPx4) and selenoprotein P (SelPP) that have roles against oxidative ***:Forty female mice were randomly assigned into natural control (CON), positive control (ETOH), low-, medium-, and high-α-tocopherol-supplemented-ethanol groups (LTOC, MTOC, HTOC, respectively). CON received drinking water without ethanol while ETOH, LTOC, MTOC and HTOC groups received 20% ethanol in drinking water. The supplemented groups were given respective dosages ofα-tocopherol, 0.410, 0.819, and 1.640 mg/g body weight, at day 14 before mating onwards to the day 9 of gestation. At 10.5 ED of gestation (1100 h), the pregnant females were sacrificed by cervical dislocation and the embryos were harvested. Total RNA were extracted, cDNA synthesis and qRT- PCR analyses were carried ***: The level of expression of PHGPx in the positive control was significantly lower than that of the natural control. Among the threeα-tocopherol-supplemented groups, only the medium dose- group was significantly higher than the positive control. The level of expression of SelPP in the positive control was significantly lower than those of the natural control, the low- and medium- dose -tocopherol supplemented groups. In the high dose-α-tocopherol supplemented group, the level of expression was not significantly different from the positive control but significantly lower than the natural ***: The activity of the selenoproteins PHGPx and SelPP are involved in the internetwork of antioxidative enzymes with vitamin E when given up to a medium dose only and is one of the possible pathways of shielding embryonic development against the impact of ethanol on brain morphogenesis. This study strengthens the impact of dietaryα-tocopherol and Selenium supplement during the criti

关键词： α-tocopherol Dysmorphogenesis Ethanol PHGPx Postimplantation embryos Selenoproteins SelPP

α-tocopherol苯并二氢吡喃骨架的不对称合成

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α-Tocopherol苯并二氢吡喃骨架的不对称合成

作者：王豪重庆大学

学位级别：硕士

Vitamin E化合物家族包括tocopherols和Tocotrienols两类共八种异构体。1922年,Evans和同事研究发现Vitamin E对生殖过程有很重要的作用。之后Evans教授从麦胚油中分离得到了Vitamin E家族中的α-tocopherol并由Fernholz教授鉴定了其结... 详细信息

Vitamin E化合物家族包括tocopherols和Tocotrienols两类共八种异构体。1922年,Evans和同事研究发现Vitamin E对生殖过程有很重要的作用。之后Evans教授从麦胚油中分离得到了Vitamin E家族中的α-tocopherol并由Fernholz教授鉴定了其结构。α-tocopherol具有许多重要的生理活性,包括促进生殖、保护红细胞、保护淋巴细胞、抗自由基氧化以及抑制血小板聚集等。由于其显著的生理活性,科学家们近几十年来一直致力于其不对称全合成研究,但是如何高效的构建其2位手性季碳中心仍旧是现在研究的热点和难点。本论文研究内容:以不对称烯丙基烷基化反应高效构建其2位手性季碳中心,然后经过修饰得到α-tocopherol的关键苯并二氢吡喃双环骨架。以三甲基氢醌10为原料,经常规的保护基修饰得到单保护酚57。利用钯催化的不对称烯丙基烷基化反应(Asymmetric Allylic Alkylation reaction,AAA reaction),57和单氧化异戊二烯51偶联生成高烯丙醇56。在综合考察了溶剂、温度、配体、酸以及各种季胺盐的影响后,56的产率达到了90%,且ee值从43%提高到92%,从而高对映选择性的构建了2位手性季碳中心。在成功制得56后,经保护、硼羟基化、Dess-Martin氧化和酸作用下环化得到烯烃67,最后经催化氢化完成了α-tocopherol的关键苯并二氢吡喃双环骨架54的合成。54与类异戊二烯侧链缩合可方便的完成α-tocopherol的不对称全合成。在整个合成路线当中,我们以三甲基氢醌10为原料,经8步反应以21%的总收率完成苯并二氢吡喃骨架54的不对称合成,该策略不仅可用于α-tocopherol的全合成,而且也为Vitamin E家族其他化合物的合成提供了一条可行的方法。

关键词： Vitamin E α-tocopherol 不对称烯丙基烷基化反应不对称合成

Protective Effects of α-tocopherol against Brain Tissue Damage Induced by Intracerebral Hemorrhage in SD Rats

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World Journal of Neuroscience 2016年第1期6卷 62-74页

作者： Zhiyong Chen Jinfu Yang Fuyin Ren Weiwei Ye Guangyong Wu Department of Neurosurgery The Third Xiangya Hospital of Central South University Changsha China

Lipid peroxidation mediated by oxygen radical is one of the main mechanisms underlying secondary brain injury. Among all vitamin E compounds, α-tocopherol shows the most prominent antioxidative effects. It plays an important role in cell aging and injury. However, there has been no report regarding the effects of α-tocopherol on changes in brain tissue morphology after intracerebral hemorrhage (ICH), cerebral edema, or the expression of Bax and Bcl-2 proteins. We use SD rats to carry out the related studies;based on the atlas of SD rats, the caudate nucleus was positioned using a stereotaxic apparatus, and 50 μl autologous tail artery blood was injected to caudate nucleus in the ICH and α-tocopherol groups to establish ICH model. Rats in the sham surgery group received the same volume of saline in the caudate nucleus. Rats in the α-tocopherol group received intraperitoneal injections of α-tocopherol at 600 mg/kg every day. Rats in the ICH group and sham surgery group received the same amount of saline at the same times as those in the α-tocopherol group. We observed some interesting results: comparisons of brain tissue sections of rats from different groups showed that brain tissue damage and functional neurological deficits among rats from the α-tocopherol group were less pronounced than in the ICH group. Wet weight/ dry weight measurement showed that rats from the α-tocopherol group exhibited less cerebral edema than those in the ICH group. Rats from the α-tocopherol group showed less Bax expression and more Bcl-2 expression than those in the ICH group.

关键词： α-tocopherol Intracerebral Hemorrhage (ICH) Cerebral Edema Bax Bcl-2

A Methodological Approach to Study Almond Oil Stability in Relation to <i>α</i>-tocopherol Supplementation

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Food and Nutrition Sciences 2012年第12期3卷 1710-1715页

作者： Lizette Auezova Chawki Saliba Elie Hajj-Moussa Leina El Hosry Said Yammine Ramez Chahine Department of Chemistry Faculty of Sciences II Lebanese University Fanar Jdaidet el Matn Lebanon Faculty of Agriculture and Veterinary Sciences Lebanese University Dekwaneh Beirut Lebanon Faculty of Medical Sciences Lebanese University Hadath Campus Beirut Lebanon Faculty of Pharmacy Lebanese University Hadath Campus Beirut Lebanon

The objectives of the present study were to identify a suitable parameter to assess the oil oxidation and to study the possibilities of delaying the oxidation of moderately oxidized unrefined almond oil by adding supplementary amounts of α-tocopherol. Three oil samples, with initial peroxide values of 13.3, 19.5 (moderately oxidized oils), and 28.9 (oxidized oil), were supplemented with 100, 250 and 500 ppm of α-tocopherol and subjected to the oxidation at 50°C for 9 days. The level of oxidation was determined by measuring peroxide value (PV), conjugated dienes (CD) and thiobarbituric acid reactive substances (TBARS). Chemometric analysis indicated that, under the conditions of the present study, PV was the most suitable indicator of oil oxidation. The results have shown that the α-tocopherol could have an anti- oxidant or pro-oxidant effects, depending on its concentration and initial level of oil oxidation. Results also show that α-tocopherol addition at all the concentrations tested resulted in pro-oxidation of the moderately oxidized oils;hence additional supplementation with α-tocopherol could not be recommended to delay oxidation of unrefined almond oil.

关键词： Almond Oil Oxidative Stability α-tocopherol PV CD TBARS Chemometrics

Effect of Polysaccharide Species on Storage Stability of Alginate Capsules Containing <i>α</i>-tocopherol

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Journal of Encapsulation and Adsorption Sciences 2015年第3期5卷 111-120页

作者： Yusuke Sato Yoshinari Taguchi Masato Tanaka Graduate School of Science and Technology Niigata University Niigata-shi Japan

Alginate capsules containing α-tocopherol were prepared adding polysaccharide species such as κ-carrageenan, gellan gum, pectin, curdlan and ghatti gum. The effects of polysaccharide species and the diameters of α-tocopherol on storage stability of the capsules were investigated and characterized in detail. As the contact angle of α-tocopherol to the capsule shell strongly affected storage stability, the contact angle was measured on the model sheet made of calcium alginate with polysaccharide species. The leakage ratio decreased with the contact angle and increased with the diameter of α-tocopherol. The capsules made of calcium alginate with gellan gum showed the largest contact angle and the highest storage stability. The capsules made of calcium alginate with curdlan, ghatti gum and pectin were harder than other capsules and showed higher storage stability. All the capsules showed the almost similar swelling ratio in the acidic solution with pH 4, but showed the different swelling ratios according to the polysaccharide species in the alkali solution with pH 9. The tablets were prepared with the wet and the dried capsules. The tablets prepared with the dried capsules showed higher storage stability.

关键词： Calcium Alginate Capsules α-tocopherol Gelling in Liquid Method Polysaccharides Storage Stability pH-Responsible Capsules

Alpha-tocopherol supplementation on chromium toxicity: a study on rat liver and kidney cell membrane

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Journal of Environmental Sciences 2003年第3期15卷 356-359页

作者： Sankar Kumar Dey Prasunpriya Nayak Somenath Roy Department of Human Physiology with Community Health Vidyasagar UniversityDepartment of Human Physiology with Community Health Vidyasagar UniversityDepartment of Human Physiology with Community Health Vidyasagar University Midnapore-721 102 West Bengal IndiaMidnapore-721 102 West Bengal IndiaMidnapore-721 102 West Bengal India

Membrane damage is one of the important consequence of chromium, an environmental toxicant, to produce cytotoxicity. α-tocopherol, a membrane protectant can be used to reduce the chromium-induced membrane damage. In the present study, the impact of chromium in presence and absence of α-tocopherol was studied on plasma membrane of liver and kidney in male Wistar rats (80—100 g body weight). Significant increase in membrane cholesterol level as well as significant decrease in membrane phospholipid level in chromium exposed ( 0.8 mg /100 g body weight/d, i.p., for 4 weeks) animals suggest structural alteration of both liver and kidney plasma memebrane. The alkaline phosphatase, total ATPase and Na +-K +-ATPase activities of plasma membrane were significantly decreased in both liver and kidney after chromium treatment. However, α-tocopherol (30 mg/100 g diet) supplementation can restrict the changes in these membrane-bound enzyme activities. Thus, the usefulness of dietary supplementation of α-tocopherol to restrain the chromium-induced membrane damage is suggested.

关键词： chromium liver kidney membrane α-tocopherol

Influence of Glutaraldehyde on the Properties and Release Kinetic of α-tocopherol from Chitosan-based Film

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Agricultural Biotechnology 2020年第1期9卷 85-88,95页

作者： Thanakorn YEAMSUKSAWAT Jun LIANG State Key Laboratory of Food Nutrition and Safety Tianjin University of Science and Technology

A crosslinked chitosan film with α-tocopherol was produced by a solution casting method. The appearance, mechanical properties, morphology, barrier properties and release kinetics of the α-tocopherol were evaluated. The addition of glutaraldehyde and α-tocopherol decreased the lightness and greenness and increased the yellowness of the chitosan-based film. Moreover, it also affected the compatibility of the film due to a decrease in the opacity values. The elongation at break(EB) and tensile strength(TS) values of the film decreased when the glutaraldehyde and α-tocopherol were added. In contrast, the Young’s modulus(YM) values increased. SEM micrographs showed coarse spots and pores on the surface and cross-section of the film when compared with the chitosan film. Based on the results, it was indicated that the chitosan structure was disconnected by the α-tocopherol, and the glutaraldehyde as a crosslinking agent generated a link between the chitosan network, which could be the cause of the reduced flexibility and the increased surface roughness of the film. However, the glutaraldehyde and α-tocopherol did not result in a significant difference in water vapour permeability(WVP) values. The glutaraldehyde influenced the release kinetics of the α-tocopherol as seen by the decrease of the diffusion coefficient values that were calculated using the Fickian diffusion model.

关键词： Release kinetic Glutaraldehyde α-tocopherol Chitosan Active film

Neuroprotective effects of low-concentration alpha-tocopherol Confocal laser microscopy observations

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Neural Regeneration Research 2009年第2期4卷 135-138页

作者： Weilun Liang Huiling Huang Qiaoli Wu Chen Wang Wenzhi Zhang Xin Su Dashi Zhi Department of Neurosurgery Tianjin Huanhu Hospital Tianjin 300072 China Institute of Neurosurgery Tianjin Huanhu Hospital Tianjin 300071 China

BACKGROUND： Alpha-tocopherol （ α-tocopherol） can effectively relieve neuronal damage induced by oxygen-centered free radicals. However, the effective dose remains controversial. OBJECTIVE： To evaluate the protective effects of low-concentration α-tocopherol on neuronal membranes. DESIGN, TIME AND SETTING： Contrast observation and in vitro study, performed at Laboratory of Neurosurgery, Tianjin Huanhu Hospital between April and September 2006. MATERIALS： Fetal cortical neurons were derived from two 14-day pregnant SD rats, and α-tocopherol was provided by Sigma, USA. METHODS： The neurons were randomly assigned to six groups：（1） normal： neurons were cultured under normal conditions; （2） oxidative damage： oxidative free radicals was damaged using the Fenton reaction; （3） α-tocopherol： neurons were cultured in different concentrations of -tocopherol 10, 20, 40, and 80 mg/L for 2 hours, respectively. MAIN OUTCOME MEASURES： Neuronal membrane damage was observed using a confocal laser microscope, and malonaldehyde production was detected using the thiobarbituric acid method. RESULTS： At normal, biological concentrations （10 mg/L）, α-tocopherol induced no change in the damaged neurons （P 〉 0.05）. However, at a concentration of 80 mg/L, the number of damaged neurons was significantly reduced, compared with the damage group （P 〈 0.05）. Malonaldehyde levels following 80 mg/L α-tocopherol treatment were less than the oxygen free radical damage group （P 〈 0.05）, but greater than the control group （P 〈 0.01）. CONCLUSION： A concentration of 80 mg/L α-tocopherol can effectively protect the neuronal cell membrane from oxidative damage

关键词： α-tocopherol confocal laser microscopy cell membrane low-concentration

GmTMT2a from soybean elevates the a-tocopherol content in corn and Arabidopsis

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GmTMT2a from soybean elevates the a-tocopherol content in co...