Vitamin E最新文献

CHAPTER 1. Vitamin E: Structure, Properties and Functions 第1章。维生素E:结构、性质和功能

Vitamin E Pub Date : 2019-02-04 DOI: 10.1039/9781788016216-00001

E. Niki, K. Abe

引用次数: 20

CHAPTER 4. Chemical Reactivity and Cellular Uptake of Tocopherols and Tocotrienols 第四章。生育酚和生育三烯醇的化学反应性和细胞摄取

Vitamin E Pub Date : 2019-02-04 DOI: 10.1039/9781788016216-00051

Yoshiro Saito, Y. Yoshida

引用次数: 4

CHAPTER 14. Metabolism of Vitamin E 第14章。维生素E的代谢

Vitamin E Pub Date : 2019-02-04 DOI: 10.1039/9781788016216-00189

R. Brigelius-Flohé

引用次数: 1

CHAPTER 6. Tocopheryl Phosphate 第六章。生育酚磷酸

Vitamin E Pub Date : 2019-02-04 DOI: 10.1039/9781788016216-00075

A. Azzi

{"title":"CHAPTER 6. Tocopheryl Phosphate","authors":"A. Azzi","doi":"10.1039/9781788016216-00075","DOIUrl":"https://doi.org/10.1039/9781788016216-00075","url":null,"abstract":"Older studies of the phosphoric acid ester of α-tocopherol (TP) in enzymes and animal models have given no conclusive results. More recently, the molecule has been the object of new scientific attention as an extension to the renewed popularity of vitamin E (α-tocopherol). α-Tocopherol is a micronutrient that is needed to prevent a form of cerebellar ataxia, but several alleged functions have been attributed to it, including protection against neurodegeneration, atherosclerosis, cancer and aging. Initially, the biological function of TP was seen as a pro-vitamin E capable of releasing α-tocopherol in the body. Subsequent studies have indicated that the nanomolar amount of TP in the body is not compatible with functioning as a reserve of vitamin E, whose concentration in plasma is in the micromolar order. On the other hand, its existence in humans, animals and plants has prompted studies on TP's molecular functions, and these have revealed that it can be synthesized and hydrolyzed in cells and in animals. The enzymes responsible for α-tocopherol kinase and tocopheryl phosphate phosphatase cellular activities have not been purified. TP inhibits cell proliferation and regulates gene expression more potently than α-tocopherol; furthermore, some genes are exclusively regulated by TP. These signaling effects of TP are in connection with phosphatidyl inositol kinase. In animal models, TP has shown more potency than α-tocopherol against atherosclerosis and inflammation. TP has been proposed to be an activated form of α-tocopherol.","PeriodicalId":23674,"journal":{"name":"Vitamin E","volume":"42 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-02-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88239177","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

CHAPTER 5. α-Tocopherol Transfer Protein 第五章。α-生育酚转移蛋白

Vitamin E Pub Date : 2019-02-04 DOI: 10.1039/9781788016216-00064

N. Kono, H. Arai

引用次数: 1

CHAPTER 12. Action of Vitamin E Against Lipid Peroxidation and Cell Death 第十二章。维生素E对脂质过氧化和细胞死亡的作用

Vitamin E Pub Date : 2019-02-04 DOI: 10.1039/9781788016216-00165

N. Noguchi

{"title":"CHAPTER 12. Action of Vitamin E Against Lipid Peroxidation and Cell Death","authors":"N. Noguchi","doi":"10.1039/9781788016216-00165","DOIUrl":"https://doi.org/10.1039/9781788016216-00165","url":null,"abstract":"It has been known that a major role of vitamin E is to inhibit lipid peroxidation by scavenging a lipid peroxyl radical by donating an electron and hydrogen from the phenol group on the chroman ring. The radical scavenging activity of tocopherols in solution is dependent on the methyl substituents on the chroman ring but not on the side chain at the C-2 position. Therefore, tocopherol (Toc) and tocotrienol (Toc3) show almost the same efficacy in the inhibition of lipid peroxidation in solution. However, the action of vitamin E in the cell is more complicated and is dependent on the efficacy of its incorporation, retention, and mobility, which in turn are affected by the nature of the side chains. Toc3 shows an advantage in the inhibition of oxidative-stress-involved alteration of a cell's function due to its higher uptake by the cell. The critical effect of the side chain of vitamin E has been implicated in the inhibition of cell death, depending on what causes the cell death. For example, the cell death induced by 24S-hydroxycholesterol was inhibited by Toc but not by Toc3. In this chapter, the efficacy of vitamin E homologues in the inhibition of lipid peroxidation under different conditions and against cell death caused by different stimuli is described.","PeriodicalId":23674,"journal":{"name":"Vitamin E","volume":"87 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-02-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78067001","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

CHAPTER 3. The Behaviour of Vitamin E in Membranes 第三章。维生素E在细胞膜中的行为

Vitamin E Pub Date : 2019-02-04 DOI: 10.1039/9781788016216-00032

J. Atkinson, D. Marquardt, T. Harroun

引用次数: 4

CHAPTER 13. Oxidation Products of Vitamin E with Lipid-derived Free Radicals 第13章。维生素E与脂质自由基的氧化产物

Vitamin E Pub Date : 2019-02-04 DOI: 10.1039/9781788016216-00175

R. Yamauchi

{"title":"CHAPTER 13. Oxidation Products of Vitamin E with Lipid-derived Free Radicals","authors":"R. Yamauchi","doi":"10.1039/9781788016216-00175","DOIUrl":"https://doi.org/10.1039/9781788016216-00175","url":null,"abstract":"Vitamin E is the most important lipophilic antioxidant in vivo and in vitro, which scavenges lipid-derived free radicals. This chapter has reviewed the oxidation products of two vitamin E compounds, α- and γ-tocopherols (αTH and γTH), during the degradation process of lipid hydroperoxides. Lipid hydroperoxides, the primary products of lipid peroxidation, are decomposed by transition metal ions or heme compounds to produce a wide range of secondary products, such as some toxic aldehydes. Since this process takes place via free radical reactions in lipophilic circumstances, THs can suppress the formation of such secondary products by trapping free-radical intermediates in micellar and liposomal systems. The oxidation products of αTH during the degradation process of lipid hydroperoxides are α-tocopherylquinone, 8a-(epoxylipid-dioxy)-α-tocopherones, 6-O-epoxylipid-αTHs, and αTH dimer. The products of γTH with lipid hydroperoxide-derived free radicals are tocored, γ-tocopherylquinone, 8a-(epoxylipid-dioxy)-γ-tocopherones, 6-O-epoxylipid-γTHs, and two γTH dimers. The produced γTH dimers are still effective in trapping lipid hydroperoxide-derived free radicals and form some addition products.","PeriodicalId":23674,"journal":{"name":"Vitamin E","volume":"28 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-02-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78955283","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

CHAPTER 8. Reactive Oxygen Species in Biological Systems 第八章。生物系统中的活性氧

Vitamin E Pub Date : 2019-02-04 DOI: 10.1039/9781788016216-00098

C. Winterbourn

引用次数: 3

CHAPTER 16. Essentiality, Bioavailability, and Health Benefits of α-Tocopherol Stereoisomers 第十六章。α-生育酚立体异构体的必要性、生物利用度和健康益处

Vitamin E Pub Date : 2019-02-04 DOI: 10.1039/9781788016216-00228

R. Bruno

{"title":"CHAPTER 16. Essentiality, Bioavailability, and Health Benefits of α-Tocopherol Stereoisomers","authors":"R. Bruno","doi":"10.1039/9781788016216-00228","DOIUrl":"https://doi.org/10.1039/9781788016216-00228","url":null,"abstract":"Vitamin E is the term that describes eight structurally-related vitamers, specifically four tocopherols (α-, β-, γ-, and δ-) and four tocotrienols (α-, β-, γ-, and δ-). Although each vitamer has antioxidant activity that prevents the cyclic progression of lipid peroxidation, α-tocopherol is the only form that is essential for humans because it prevents and reverses clinical deficiency of vitamin E. These vitamers also differ substantially in their bioavailability, which results in α-tocopherol accumulating to the greatest extent in the circulation and tissues in humans. In nature, α-tocopherol exists as a single stereoisomer (2R, 4′R, 8′R- or RRR-α-tocopherol) whereas most dietary supplements and fortified foods contain an all racemic mixture of eight α-tocopherol stereoisomers. Importantly, only 50% of these stereoisomers are appreciably bioavailable, and therefore capable of contributing to dietary α-tocopherol requirements in humans. This chapter will therefore focus on the bioavailability, metabolism, and trafficking of vitamin E forms along the gut–liver axis. It will also discuss their structure–function aspects concerning their ability to contribute to dietary vitamin E requirements and associated health benefits.","PeriodicalId":23674,"journal":{"name":"Vitamin E","volume":"21 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-02-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91005478","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2