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Bampidis V, Azimonti G, Bastos MDL, Christensen H, Dusemund B, Fašmon Durjava M, Kouba M, López-Alonso M, López Puente S, Marcon F, Mayo B, Pechová A, Petkova M, Ramos F, Sanz Y, Villa RE, Woutersen R, Aquilina G, Dierick N, Padovani A, Anguita M, Galobart J, Casanova JO, Tarrés-Call J. Safety and efficacy of a feed additive consisting of tocopheryl phosphate mixture (TPM) for all animal species (Avecho biotechnology limited). EFSA J 2022; 20:e07438. [PMID: 35873723 PMCID: PMC9301928 DOI: 10.2903/j.efsa.2022.7438] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Following a request from the European Commission, the Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) was asked to deliver a scientific opinion on the safety and efficacy of tocopheryl phosphate mixture (TPM) as nutritional feed additive for all animal species. The additive has not been authorised for use in animal nutrition. TPM is produced by chemical synthesis and is a mixture of two different phosphorylated tocopheryl compounds in approximate 2:1 weight ratio: all‐rac‐α‐tocopheryl di‐hydrogen phosphate (TP) and all‐rac‐di‐α‐tocopheryl hydrogen phosphate (T2P). It is intended to be used as nutritional additive (as a source of vitamin E) in feed for all animal species and categories. Considering the limited information on the ADMER for the components of the additive and the uncertainties on the potential aneugenicity and clastogenicity of the additive, the Panel cannot conclude on the safety of the additive for the target species and for the consumer. TPM is not a skin irritant nor a skin sensitiser but should be considered irritant to the eyes and the upper respiratory tract. Owing to the uncertainty on the potential aneugenicity and clastogenicity of the additive, it is not possible to conclude on safety for the user. The FEEDAP Panel cannot conclude on the safety of TPM for the environment due to lack of data on environmental impact of T2P. TPM is a bioavailable source of α‐tocopherol. The data available, however, do not allow the Panel to establish the relative bioequivalence of TPM as vitamin E. Therefore, the Panel is not in the position to conclude on the efficacy of TPM for all animal species.
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Zingg JM, Stamatiou C, Montalto G, Daunert S. Modulation of CD36-mediated lipid accumulation and senescence by vitamin E analogs in monocytes and macrophages. Biofactors 2022; 48:665-682. [PMID: 35084073 DOI: 10.1002/biof.1821] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/27/2021] [Accepted: 12/14/2021] [Indexed: 01/10/2023]
Abstract
The CD36/FAT scavenger receptor/fatty acids transporter regulates cellular lipid accumulation important for inflammation, atherosclerosis, lipotoxicity, and initiation of cellular senescence. Here we compared the regulatory effects of the vitamin E analogs alpha-tocopherol (αT), alpha-tocopheryl phosphate (αTP), and αTP/βCD (a nanocarrier complex between αTP and β-cyclodextrin [βCD]) and investigated their regulatory effects on lipid accumulation, phagocytosis, and senescence in THP-1 monocytes and macrophages. Both, αTP and αTP/βCD inhibited CD36 surface exposition stronger than αT leading to more pronounced CD36-mediated events such as inhibition of DiI-labeled oxLDL uptake, phagocytosis of fluorescent Staphylococcus aureus bioparticles, and cell proliferation. When compared to βCD, the complex of αTP/βCD extracted cholesterol from cellular membranes with higher efficiency and was associated with the delivery of αTP to the cells. Interestingly, both, αTP and more so αTP/βCD inhibited lysosomal senescence-associated beta-galactosidase (SA-β-gal) activity and increased lysosomal pH, suggesting CD36-mediated uptake into the endo-lysosomal phagocytic compartment. Accordingly, the observed pH increase was more pronounced with αTP/βCD in macrophages whereas no significant increase occurred with αT, alpha-tocopheryl acetate (αTA) or βCD. In contrast to αT and αTA, the αTP molecule is di-anionic at neutral pH, but upon moving into the acidic endo-lysosomal compartment becomes protonated and thus is acting as a base. Moreover, it is expected to be retained in lysosomes since it still carries one negative charge, similar to lysosomotropic drugs. Thus, treatment with αTP or αTP/βCD and/or inhibition of conversion of αTP to αT as it occurs in aged cells may counteract CD36-mediated overlapping inflammatory, senescent, and atherosclerotic events.
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Affiliation(s)
- Jean-Marc Zingg
- Department of Biochemistry and Molecular Biology, Miller School of Medicine, University of Miami, Miami, Florida, USA
- Dr. JT Macdonald Foundation Biomedical Nanotechnology Institute, University of Miami, Miami, Florida, USA
| | - Christina Stamatiou
- Department of Biochemistry and Molecular Biology, Miller School of Medicine, University of Miami, Miami, Florida, USA
- Dr. JT Macdonald Foundation Biomedical Nanotechnology Institute, University of Miami, Miami, Florida, USA
| | - Giulia Montalto
- Department of Biochemistry and Molecular Biology, Miller School of Medicine, University of Miami, Miami, Florida, USA
- Section of General Pathology, Department of Experimental Medicine, University of Genoa, Genoa, Italy
| | - Sylvia Daunert
- Department of Biochemistry and Molecular Biology, Miller School of Medicine, University of Miami, Miami, Florida, USA
- Dr. JT Macdonald Foundation Biomedical Nanotechnology Institute, University of Miami, Miami, Florida, USA
- University of Miami Clinical and Translational Science Institute, University of Miami, Miami, Florida, USA
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Garg A, Lee JCY. Vitamin E: Where Are We Now in Vascular Diseases? Life (Basel) 2022; 12:life12020310. [PMID: 35207597 PMCID: PMC8874674 DOI: 10.3390/life12020310] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Revised: 02/07/2022] [Accepted: 02/14/2022] [Indexed: 12/19/2022] Open
Abstract
Vitamin E is one of the most popular fat-soluble vitamins in pathological research and has been under scrutiny since the 1980s as a vital dietary component of food. The antioxidant effect of vitamin E has been widely studied due to its benefits in the prevention of various cardiovascular diseases. In recent years, alternative effects of vitamin E, in terms of anti-inflammatory pathways and gene regulation, have also been of interest to researchers. This review examines the role of dietary vitamin E (α-tocopherol) as an antioxidant and bioactive molecule in promoting vascular health. While the antioxidant effect of vitamin E is well established, knowledge about its capacity as a promising regulatory molecule in the control of the vascular system is limited. The aim of this review is to discuss some of these mechanisms and summarize their role in the prevention of cardiovascular diseases (CVD). Here, we also briefly discuss foods rich in vitamin E, and deliberate some potential toxicological effects of excessive supplemental vitamin E in the body.
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Azzi A. Reflections on a century of vitamin E research: Looking at the past with an eye on the future. Free Radic Biol Med 2021; 175:155-160. [PMID: 34478835 DOI: 10.1016/j.freeradbiomed.2021.07.042] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Revised: 07/15/2021] [Accepted: 07/25/2021] [Indexed: 12/30/2022]
Abstract
The name vitamin E, was given by Barnett and Sure who suggested that the factor proposed by Evans and Bishop as substance "X," be termed vitamin "E" as the next vitamin after the A, B, C and D vitamins had been already described. The identification of vitamin E with a-tocopherol was made in 1936 by Evans' group. One year later β-tocopherol and 11 years later δ-tocopherol were isolated. Tocotrienol (named zetatocopherol) was first described in 1957 and later isolated in 1961. The antioxidant property of tocopherols was reported by Olcott and Emerson in 1937. Inherited vitamin E deficiency, AVED, characterized by a form of neuromyopathy was first described in 1981. The disease, was localized to chromosome 8q and found to be caused by a mutation of the a-TTP gene. The subsequent paragraphs are not a comprehensive review but only critical reflections on some important aspects of vitamin E research.
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Affiliation(s)
- Angelo Azzi
- School of Graduate Biomedical Pharmacology and Drug Development Program, Tufts University, Boston, MA, 02116, USA.
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Sozen E, Demirel T, Ozer NK. Vitamin E: Regulatory role in the cardiovascular system. IUBMB Life 2019; 71:507-515. [PMID: 30779288 DOI: 10.1002/iub.2020] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Accepted: 01/24/2019] [Indexed: 12/22/2022]
Abstract
Cardiovascular disease (CVD) is one of the major causes of morbidity and mortality, all around the world. Vitamin E is an important nutrient influencing key cellular and molecular mechanisms as well as gene expression regulation centrally involved in the prevention of CVD. Cell culture and animal studies have focused on the identification of vitamin E regulated signaling pathways and involvement on inflammation, lipid homeostasis, and atherosclerotic plaque stability. While some of these vitamin E functions were verified in clinical trials, some of the positive effects were not translated into beneficial outcomes in epidemiological studies. In recent years, the physiological metabolites of vitamin E, including the liver derived (long- and short-chain) metabolites and phosphorylated (α-, γ-tocopheryl phosphate) forms, have also provided novel mechanistic insight into CVD regulation that expands beyond the vitamin E precursor. It is certain that this emerging insight into the molecular and cellular action of vitamin E will help to design further studies, either in animal models or clinical trials, on the reduction of risk for CVDs. This review focuses on vitamin E-mediated preventive cardiovascular effects and discusses novel insights into the biology and mechanism of action of vitamin E metabolites in CVD. © 2019 IUBMB Life, 71(4):507-515, 2019.
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Affiliation(s)
- Erdi Sozen
- Department of Biochemistry, Faculty of Medicine, Genetic and Metabolic Diseases Research and Investigation Center (GEMHAM), Marmara University, Istanbul, Turkey
| | - Tugce Demirel
- Department of Biochemistry, Faculty of Medicine, Genetic and Metabolic Diseases Research and Investigation Center (GEMHAM), Marmara University, Istanbul, Turkey
| | - Nesrin Kartal Ozer
- Department of Biochemistry, Faculty of Medicine, Genetic and Metabolic Diseases Research and Investigation Center (GEMHAM), Marmara University, Istanbul, Turkey
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6
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Zingg JM. Vitamin E: Regulatory Role on Signal Transduction. IUBMB Life 2018; 71:456-478. [PMID: 30556637 DOI: 10.1002/iub.1986] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Revised: 11/20/2018] [Accepted: 11/21/2018] [Indexed: 01/02/2023]
Abstract
Vitamin E modulates signal transduction pathways by several molecular mechanisms. As a hydrophobic molecule located mainly in membranes it contributes together with other lipids to the physical and structural characteristics such as membrane stability, curvature, fluidity, and the organization into microdomains (lipid rafts). By acting as the main lipid-soluble antioxidant, it protects other lipids such as mono- and poly-unsaturated fatty acids (MUFA and PUFA, respectively) against chemical reactions with reactive oxygen and nitrogen species (ROS and RNS, respectively) and prevents membrane destabilization and cellular dysfunction. In cells, vitamin E affects signaling in redox-dependent and redox-independent molecular mechanisms by influencing the activity of enzymes and receptors involved in modulating specific signal transduction and gene expression pathways. By protecting and preventing depletion of MUFA and PUFA it indirectly enables regulatory effects that are mediated by the numerous lipid mediators derived from these lipids. In recent years, some vitamin E metabolites have been observed to affect signal transduction and gene expression and their relevance for the regulatory function of vitamin E is beginning to be elucidated. In particular, the modulation of the CD36/FAT scavenger receptor/fatty acids transporter by vitamin E may influence many cellular signaling pathways relevant for lipid homeostasis, inflammation, survival/apoptosis, angiogenesis, tumorigenesis, neurodegeneration, and senescence. Thus, vitamin E has an important role in modulating signal transduction and gene expression pathways relevant for its uptake, distribution, metabolism, and molecular action that when impaired affect physiological and patho-physiological cellular functions relevant for the prevention of a number of diseases. © 2018 IUBMB Life, 71(4):456-478, 2019.
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Affiliation(s)
- Jean-Marc Zingg
- Department of Biochemistry and Molecular Biology, Miller School of Medicine, University of Miami, Miami, Florida, USA
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7
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Khadangi F, Azzi A. Vitamin E - The Next 100 Years. IUBMB Life 2018; 71:411-415. [PMID: 30550633 DOI: 10.1002/iub.1990] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2018] [Revised: 11/13/2018] [Accepted: 11/24/2018] [Indexed: 12/16/2022]
Abstract
α-Tocopherol is the only tocopherol that has been shown to prevent the human deficiency disease Ataxia with Isolated Vitamin E Deficiency (AVED), and thus it is the only one that, for humans, can be called vitamin E. Vitamin E in addition to preventing AVED has documented immune boosting properties and an activity against nonalcoholic hepatosteatosis and low-grade inflammation. Epidemiological studies indicating that vitamin E could prevent cardiovascular events, neurodegenerative disease, macular degeneration, and cancer were in general not confirmed by clinical intervention studies. Vitamin E and some of its metabolites modulate cell signaling and gene transcription. Future research is needed to achieve a better understanding of the molecular events leading to gene regulation by vitamin E, especially in its phosphorylated form. Isolation and characterization of the vitamin E kinase and vitamin E phosphate phosphatase will help in the understanding of cell regulation processes modulated by vitamin E. A clarification of the pathogenesis of AVED remains an important goal to be achieved. © 2018 IUBMB Life, 71(4):411-415, 2019.
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Affiliation(s)
| | - Angelo Azzi
- Vascular Biology Laboratory, JM USDA-HNRCA at Tufts University, Boston, Massachusetts
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8
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Abstract
The hydrophobicity of vitamin E poses transport and metabolic challenges to regulate its bioavailability and to prevent its accumulation in lipid-rich tissues such as adipose tissue, brain, and liver. Water-soluble precursors of vitamin E (α-tocopherol, αT), such as its esters with acetate (αTA), succinate (αTS), or phosphate (αTP), have increased solubility in water and stability against reaction with free radicals, but they are rapidly converted during their uptake into the lipid-soluble vitamin E. Therefore, the bioavailability of these precursors as intact molecules is low; nevertheless, at least for αTS and αTP, the recent research has revealed unique regulatory effects on signal transduction and gene expression and the modulation of cellular events ranging from proliferation, survival/apoptosis, lipid uptake and metabolism, phagocytosis, long term potentiation, cell migration, telomere maintenance, and angiogenesis. Moreover, water-soluble derivatives of vitamin E including some based on αTP are increasingly used as components of nanocarriers for enhanced and targeted delivery of drugs and other molecules (vitamins, including αT and αTP itself, vitamin D3, carnosine, caffeine, docosahexaenoic acid (DHA), insulin) and cofactors such as coenzyme Q10. In this review, the chemical characteristics, transport, metabolic pathways, and molecular mechanisms of action of αTP in cells and tissues are summarized and put into perspective with its possible role in the prevention of a number of diseases.
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Affiliation(s)
- Jean-Marc Zingg
- Miller School of Medicine, University of Miami, Miami, FL, United States.
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Libinaki R, Vinh A, Tesanovic-Klajic S, Widdop R, Gaspari T. The effect of tocopheryl phosphates (TPM) on the development of atherosclerosis in apolipoprotein-E deficient mice. Clin Exp Pharmacol Physiol 2017; 44 Suppl 1:107-116. [PMID: 28744946 DOI: 10.1111/1440-1681.12821] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2016] [Revised: 07/17/2017] [Accepted: 07/18/2017] [Indexed: 12/21/2022]
Abstract
α-Tocopheryl phosphate (TP) is a naturally occurring form of vitamin E found in the body. In the present study we compared the ability of an α-TP mixture (TPM) against a standard vitamin E supplement, α-tocopherol acetate (TA) on the development of atherosclerotic lesions in ApoE-deficient mice. Mice were maintained on either a normal chow diet for 24 weeks (Normal Diet), vs a group in which the final 8 weeks of the 24-week period mice were placed on a high fat (21%), high cholesterol (0.15%) challenge diet (HFHC), to exacerbate atherosclerotic lesion development.. The difference in these two control groups established the extent of the diet-induced atherosclerotic lesion development. Mice in the various treatment groups received either TA (300 mg/kg chow) or TPM (6.7-200 mg/kg chow) for 24 weeks, with TPM treatment resulting in dose-dependent significant reductions in atherosclerotic lesion formation and plasma levels of pro-inflammatory cytokines. TA-treated mice, with the tocopherol equivalent TPM dose (200 mg/kg chow), showed no significant reduction in plasma lipid levels or evidence for aortic lesion regression. At this TPM equivalent TA dose, a 44% reduction in aortic lesion formation was observed. In addition, these TPM treated mice, also showed a marked reduction in aortic superoxide formation and decreased circulating plasma levels of known pro-inflammatory markers IL-6, MCP-1, IL-1β, IFN-γ and TNF-α. These findings indicate that TPM treatment slows progression of atherosclerotic lesions in ApoE-deficient mice with this effect potentially involving reduced oxidative stress and decreased inflammation.
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Affiliation(s)
- Roksan Libinaki
- Phosphagenics R& D Laboratory, Clayton, Melbourne, Victoria, Australia
| | - Antony Vinh
- Department of Pharmacology, Monash University, Clayton, Melbourne, Victoria, Australia
| | | | - Robert Widdop
- Department of Pharmacology, Monash University, Clayton, Melbourne, Victoria, Australia
| | - Tracey Gaspari
- Department of Pharmacology, Monash University, Clayton, Melbourne, Victoria, Australia
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10
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Abstract
Four tocopherols are available in nature and are absorbed with the diet, but only one RRR-α-tocopherol satisfies the criteria of being a vitamin. The biological activity of the different tocopherols studied in the rat by the resorption-gestation test has been inconsistently extrapolated to human beings where the tocopherols have no influence on a successful pregnancy. Diminution of RRR-α-tocopherol intake results in diseases characterized by ataxia, whose pathogenetic mechanism, despite vigorous claims, has not been clarified. The calculation of the Daily Reference Intake (DRI), necessary to prevent disease, is based on an obsolete test, the peroxide-induced erythrocyte hemolysis, called the gold standard, but of highly questioned validity. If many epidemiological studies have given positive results, showing prevention by high vitamin E containing diets of cardiovascular events, neurodegenerative disease, macular degeneration and cancer, the clinical confirmatory intervention studies were mostly negative. On the positive side, besides preventing vitamin E deficiency diseases, vitamin E has shown efficacy as anti-inflammatory and immune boosting compound. It has also shown some efficacy in protecting against nonalcoholic hepato-steatosis. At a molecular level, vitamin E and some of its metabolites have shown capacity of regulating cell signaling and modulating gene transcription.
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Affiliation(s)
- Angelo Azzi
- Vascular Biology Laboratory, JM USDA-HNRCA at Tufts University, Boston, MA 02111, USA.
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Galli F, Azzi A, Birringer M, Cook-Mills JM, Eggersdorfer M, Frank J, Cruciani G, Lorkowski S, Özer NK. Vitamin E: Emerging aspects and new directions. Free Radic Biol Med 2017; 102:16-36. [PMID: 27816611 DOI: 10.1016/j.freeradbiomed.2016.09.017] [Citation(s) in RCA: 256] [Impact Index Per Article: 36.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/16/2016] [Revised: 09/11/2016] [Accepted: 09/22/2016] [Indexed: 12/30/2022]
Abstract
The discovery of vitamin E will have its 100th anniversary in 2022, but we still have more questions than answers regarding the biological functions and the essentiality of vitamin E for human health. Discovered as a factor essential for rat fertility and soon after characterized for its properties of fat-soluble antioxidant, vitamin E was identified to have signaling and gene regulation effects in the 1980s. In the same years the cytochrome P-450 dependent metabolism of vitamin E was characterized and a first series of studies on short-chain carboxyethyl metabolites in the 1990s paved the way to the hypothesis of a biological role for this metabolism alternative to vitamin E catabolism. In the last decade other physiological metabolites of vitamin E have been identified, such as α-tocopheryl phosphate and the long-chain metabolites formed by the ω-hydroxylase activity of cytochrome P-450. Recent findings are consistent with gene regulation and homeostatic roles of these metabolites in different experimental models, such as inflammatory, neuronal and hepatic cells, and in vivo in animal models of acute inflammation. Molecular mechanisms underlying these responses are under investigation in several laboratories and side-glances to research on other fat soluble vitamins may help to move faster in this direction. Other emerging aspects presented in this review paper include novel insights on the mechanisms of reduction of the cardiovascular risk, immunomodulation and antiallergic effects, neuroprotection properties in models of glutamate excitotoxicity and spino-cerebellar damage, hepatoprotection and prevention of liver toxicity by different causes and even therapeutic applications in non-alcoholic steatohepatitis. We here discuss these topics with the aim of stimulating the interest of the scientific community and further research activities that may help to celebrate this anniversary of vitamin E with an in-depth knowledge of its action as vitamin.
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Affiliation(s)
- Francesco Galli
- Department of Pharmaceutical Sciences, University of Perugia, Laboratory of Clinical Biochemistry and Nutrition, Via del Giochetto, 06126 Perugia, Italy.
| | - Angelo Azzi
- USDA-HNRCA at Tufts University, 711 Washington St., Boston, MA 02111, United States.
| | - Marc Birringer
- Department of Nutritional, Food and Consumer Sciences, Fulda University of Applied Sciences, Leipziger Straße 123, 36037 Fulda, Germany.
| | - Joan M Cook-Mills
- Allergy/Immunology Division, Northwestern University, 240 E Huron, Chicago, IL 60611, United States.
| | | | - Jan Frank
- Institute of Biological Chemistry and Nutrition, University of Hohenheim, Garbenstr. 28, 70599 Stuttgart, Germany.
| | - Gabriele Cruciani
- Department of Chemistry, Biology and Biotechnology, University of Perugia, Italy.
| | - Stefan Lorkowski
- Institute of Nutrition, Friedrich Schiller University Jena, Dornburger Str. 25, 07743 Jena, Germany; Competence Cluster for Nutrition and Cardiovascular Health (nutriCARD), Halle-Jena-Leipzig, Germany.
| | - Nesrin Kartal Özer
- Department of Biochemistry, Faculty of Medicine, Genetic and Metabolic Diseases Research Center (GEMHAM), Marmara University, 34854 Maltepe, Istanbul, Turkey.
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Gianello R, Hall WC, Kennepohl E, Libinaki R, Ogru E. Subchronic Oral Toxicity Study of Mixed Tocopheryl Phosphates in Rats. Int J Toxicol 2016; 26:475-90. [DOI: 10.1080/10915810701620556] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Rats were fed diets containing 0%, 1 %, 3%, or 5% mixed tocopheryl phosphates for 90 days. No abnormal clinical signs related to treatment appeared. Some statistically significant changes in hematology and clinical chemistry parameters appeared, but the majority were not dose dependent, occurred in only one sex or group, and/or remained within the historical control range for this strain of rat. A statistically significant apparent reduction in blood protein was observed in animals treated with the tocopheryl phosphates, but further investigation showed that the test substance interfered with the protein assay. Repeat analysis using a method unaffected by plasma test substance levels showed no difference in plasma proteins among all groups. Gross necropsy revealed no abnormalities; reduced relative heart and epididymal weights were observed, but were not dose dependent and were considered incidental. Histopathological changes occurred only in the mesenteric lymph node and small intestine. Foreign material in a crystal-like form appeared in macrophages in both organs, and increased in a dose-related fashion. In the lymph node, sinus histiocytosis increased with dose, but the severity was similar between the control and low-dose groups. Foreign-body granulomatous inflammation, associated with Maltese cross birefringence of the crystals was seen in the mid- and high-dose animals, but not the low-dose group. Similarly, the small intestine showed increasing amounts of foreign material and inflammation in the mid- and high-dose but not in the 1 % diet. The 1 % diet (equivalent to 587 and 643 mg mixed tocopheryl phosphates/kg body weight/day for male and female rats, respectively) was considered the no observed adverse effect level.
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Affiliation(s)
- R. Gianello
- Monash University, Department of Biochemistry and Molecular Biology, Clayton, Victoria, Australia
| | - W. C. Hall
- Hall Consulting, Inc., Mt. Airy, Maryland, USA
| | - E. Kennepohl
- Write-Tox Consulting, Spruce Grove, Alberta, Canada
| | - R. Libinaki
- Monash University, Department of Biochemistry and Molecular Biology, Clayton, Victoria, Australia
| | - E. Ogru
- Phosphagenics Ltd., Melbourne, Australia
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The rise, the fall and the renaissance of vitamin E. Arch Biochem Biophys 2016; 595:100-8. [PMID: 27095224 DOI: 10.1016/j.abb.2015.11.010] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Revised: 05/26/2015] [Accepted: 10/14/2015] [Indexed: 12/22/2022]
Abstract
This review deals with the expectations of vitamin E ability of preventing or curing, as a potent antioxidant, alleged oxidative stress based ailments including cardiovascular disease, cancer, neurodegenerative diseases, cataracts, macular degeneration and more. The results obtained with clinical intervention studies have highly restricted the range of effectiveness of this vitamin. At the same time, new non-antioxidant mechanisms have been proposed. The new functions of vitamin E have been shown to affect cell signal transduction and gene expression, both in vitro and in vivo. Phosphorylation of vitamin E, which takes place in vivo, results in a molecule provided with functions that are in part stronger and in part different from those of the non-phosphorylate compound. The in vivo documented functions of vitamin E preventing the vitamin E deficiency ataxia (AVED), slowing down the progression of non-alcoholic steato-hepatitis (NASH), decreasing inflammation and potentiating the immune response are apparently based on these new molecular mechanisms. It should be stressed however that vitamin E, when present at higher concentrations in the body, should exert antioxidant properties to the extent that its chromanol ring is unprotected or un-esterified.
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Affiliation(s)
- Jean-Marc Zingg
- Department of Biochemistry and Molecular Biology, University of Miami, Miami, Florida 33136-6129;
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Ghayour-Mobarhan M, Saghiri Z, Ferns G, Sahebkar A. α-Tocopheryl Phosphate as a Bioactive Derivative of Vitamin E: A Review of the Literature. J Diet Suppl 2014; 12:359-372. [PMID: 25238486 DOI: 10.3109/19390211.2014.952859] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
α-Tocopheryl phosphate (α-TP) is a naturally occurring derivative of α-tocopherol (α-T), one of the eight isoforms of vitamin E. α-TP is present at very low intracellular concentrations, traffics across plasma membranes, and affects many important cellular functions. In addition to being a signaling molecule, α-TP has also been shown to possess antioxidant and potentially antiatherosclerotic properties that are more potent than its parent compound (α-T). However, there is little published data on the clinical effects of α-TP supplements, the mechanisms involved in its metabolism and cellular function, and reliable methods for its determination in plasma.
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Affiliation(s)
- Majid Ghayour-Mobarhan
- a 1 Cardiovascular Research Center , Mashhad University of Medical Sciences Mashhad, Iran.,b 2 Biochemistry of Nutrition Research Center , Mashhad University of Medical Sciences Mashhad, Iran
| | - Zahra Saghiri
- c 3 Department of Biology, Faculty of Basic Sciences, Payame Noor University of Mashhad , Mashhad . Iran
| | - Gordon Ferns
- d 4 Division of Medical Education, Mayfield House , University of Brighton BN1 9PH, United Kingdom
| | - Amirhossein Sahebkar
- e 5 Neurogenic Inflammation Research Center, Department of Medical Biotechnology , Mashhad University of Medical Sciences Mashhad, Iran.,f 6 Biotechnology Research Center , Mashhad University of Medical Sciences Mashhad, Iran.,g 7 Metabolic Research Centre, Royal Perth Hospital, School of Medicine and Pharmacology , University of Western Australia Perth, Australia
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16
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Zingg JM, Libinaki R, Meydani M, Azzi A. Modulation of phosphorylation of tocopherol and phosphatidylinositol by hTAP1/SEC14L2-mediated lipid exchange. PLoS One 2014; 9:e101550. [PMID: 24983950 PMCID: PMC4077815 DOI: 10.1371/journal.pone.0101550] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2014] [Accepted: 06/09/2014] [Indexed: 11/18/2022] Open
Abstract
The vitamin E derivative, alpha-tocopheryl phosphate (αTP), is detectable in cultured cells, plasma and tissues in small amounts, suggesting the existence of enzyme(s) with α-tocopherol (αT) kinase activity. Here, we characterize the production of αTP from αT and [γ-32P]-ATP in primary human coronary artery smooth muscle cells (HCA-SMC) using separation by thin layer chromatography (TLC) and subsequent analysis by Ultra Performance Liquid Chromatography (UPLC). In addition to αT, although to a lower amount, also γT is phosphorylated. In THP-1 monocytes, γTP inhibits cell proliferation and reduces CD36 scavenger receptor expression more potently than αTP. Both αTP and γTP activate the promoter of the human vascular endothelial growth factor (VEGF) gene with similar potency, whereas αT and γT had no significant effect. The recombinant human tocopherol associated protein 1 (hTAP1, hSEC14L2) binds both αT and αTP and stimulates phosphorylation of αT possibly by facilitating its transport and presentation to a putative αT kinase. Recombinant hTAP1 reduces the in vitro activity of the phosphatidylinositol-3-kinase gamma (PI3Kγ) indicating the formation of a stalled/inactive hTAP1/PI3Kγ heterodimer. The addition of αT, βT, γT, δT or αTP differentially stimulates PI3Kγ, suggesting facilitated egress of sequestered PI from hTAP1 to the enzyme. It is suggested that the continuous competitive exchange of different lipophilic ligands in hTAPs with cell enzymes and membranes may be a way to make these lipophiles more accessible as substrates for enzymes and as components of specific membrane domains.
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Affiliation(s)
- Jean-Marc Zingg
- Vascular Biology Laboratory, JM USDA-Human Nutr. Res. Ctr. On Aging, Tufts University, Boston, Massachusetts, United States of America
- * E-mail:
| | - Roksan Libinaki
- Dept. Biochem. and Mol. Biology, Monash University, Melbourne, VIC, Australia
| | - Mohsen Meydani
- Vascular Biology Laboratory, JM USDA-Human Nutr. Res. Ctr. On Aging, Tufts University, Boston, Massachusetts, United States of America
| | - Angelo Azzi
- Vascular Biology Laboratory, JM USDA-Human Nutr. Res. Ctr. On Aging, Tufts University, Boston, Massachusetts, United States of America
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Zingg JM, Meydani M, Azzi A. α-Tocopheryl phosphate--an activated form of vitamin E important for angiogenesis and vasculogenesis? Biofactors 2012; 38:24-33. [PMID: 22281871 DOI: 10.1002/biof.198] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/16/2011] [Accepted: 12/22/2011] [Indexed: 12/13/2022]
Abstract
Vitamin E was originally discovered as a dietary factor essential for reproduction in rats. Since then, vitamin E has revealed many important molecular properties such as the scavenging of reactive oxygen and nitrogen species or the modulation of signal transduction and gene expression in antioxidant and nonantioxidant manners. A congenital disease, ataxia with vitamin E deficiency, which is characterized by impaired enrichment of α-tocopherol (αT) in plasma due to mutations in the α-tocopherol transfer protein gene, has been discovered. An effect of vitamin E on angiogenesis and vasculogenesis has been observed in several studies, and recently, it has been demonstrated in the placenta of pregnant ewes, possibly involving the stimulation of vascular endothelial growth factor (VEGF) expression. We recently observed that the phosphorylated form of αT, α-tocopheryl phosphate (αTP), increases the expression of VEGF. We propose that the stimulatory effect of αT on angiogenesis and vasculogenesis is potentiated by phosphorylation to αTP, which may act as a cofactor or active lipid mediator increasing VEGF expression. Increased VEGF expression and consequent enhanced angiogenesis and vasculogenesis induced by αTP may explain not only the essential roles of vitamin E on reproduction, but also its beneficial effects against pre-eclampsia, ischemia/reperfusion injury, and during wound healing. It may also serve as a survival factor for brain and muscle cells. The finding that αTP may regulate vasculogenesis may indicate potential, important pathophysiological implications.
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Affiliation(s)
- Jean-Marc Zingg
- Vascular Biology Laboratory, JM USDA-Human Nutrition Research Center on Aging, Tufts University, Boston, MA, USA.
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Sodium dl-α-tocopheryl-6-O-phosphate inhibits PGE2 production in keratinocytes induced by UVB, IL-1β and peroxidants. Bioorg Med Chem 2011; 19:6348-55. [DOI: 10.1016/j.bmc.2011.08.067] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2011] [Revised: 08/30/2011] [Accepted: 08/31/2011] [Indexed: 11/20/2022]
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Crouzin N, de Jesus Ferreira MC, Cohen-Solal C, M'Kadmi C, Bernad N, Martinez J, Barbanel G, Vignes M, Guiramand J. α-tocopherol and α-tocopheryl phosphate interact with the cannabinoid system in the rodent hippocampus. Free Radic Biol Med 2011; 51:1643-55. [PMID: 21843633 DOI: 10.1016/j.freeradbiomed.2011.07.012] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/04/2011] [Revised: 07/08/2011] [Accepted: 07/14/2011] [Indexed: 10/17/2022]
Abstract
α-Tocopherol (α-TOH), a dietary component of vitamin E, is well known for its antioxidant capacity. Nevertheless, recent studies have pointed out non-anti-radical properties including cellular and genomic actions. Decreased levels of α-tocopherol in the brain are associated with neuronal dysfunctions ranging from mood disorders to neurodegeneration. All these behavioral effects of α-tocopherol deficiency probably do not rely simply on its anti-radical properties, but could also be reminiscent of a not-yet characterized neuromodulatory action. We have thus measured the direct actions of α-tocopherol and of its natural phosphate derivative, α-tocopheryl phosphate (α-TP), on synaptic transmission in rodent hippocampus. These compounds had opposite actions on both glutamatergic and GABAergic transmission: whereas α-TOH potentiated these transmissions, α-TP inhibited them. Interestingly, these effects were both mediated by cannabinoid receptors (CB1Rs), because they were blocked by the CB1R antagonist AM251. Although α-tocopherol and α-tocopheryl phosphate did not directly bind CB1R, both α-TP and CB1R agonists inhibited forskolin-evoked Erk1/2 phosphorylation in a nonadditive manner. Furthermore, both α-tocopherol and α-tocopheryl phosphate attenuated depolarization-induced suppression of excitation and CB1R agonist-mediated hypothermia. Therefore, we identify α-tocopherol as new lipid modulator of the cannabinoid system in the rodent hippocampus, i.e., a novel "non-anti-radical" action of vitamin E, which may have some preeminent impact in neuronal disorders associated with vitamin E deficiency.
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Affiliation(s)
- Nadine Crouzin
- Institut des Biomolécules Max Mousseron, UMR 5247–CNRS–Université Montpellier 1–Université Montpellier 2, 34095 Montpellier Cedex 5, France
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20
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Nishio K, Ishida N, Saito Y, Ogawa-Akazawa Y, Shichiri M, Yoshida Y, Hagihara Y, Noguchi N, Chirico J, Atkinson J, Niki E. α-Tocopheryl phosphate: uptake, hydrolysis, and antioxidant action in cultured cells and mouse. Free Radic Biol Med 2011; 50:1794-800. [PMID: 21443945 DOI: 10.1016/j.freeradbiomed.2011.03.021] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/06/2010] [Revised: 03/01/2011] [Accepted: 03/21/2011] [Indexed: 02/05/2023]
Abstract
α-Tocopheryl phosphate (α-TP), a water-soluble analogue of α-tocopherol, is found in humans, animals, and plants. α-TP is resistant to both acid and alkaline hydrolysis and may exert its own function in this form in vivo. In this study, the uptake, hydrolysis, and antioxidant action of α-TP were measured using α-TP with a deuterated methyl group, CD(3), at position 5 of the chroman ring (α-TP(CD3)). The hydrolysis of α-TP(CD3) was followed by measuring α-tocopherol containing the CD(3) group, α-T(CD3), in comparison to unlabeled α-tocopherol, α-T(CH3). α-TP(CD3) was incubated with cultured cells, and the intracellular α-T(CD3) formed was measured with HPLC-ECD and GC-MS. α-TP(CD3) was also administered to mice for 4 weeks by mixing in the diet, and α-T(CD3) was measured in plasma, liver, brain, heart, and testis to compare with endogenous unlabeled α-T(CH3). It was found that α-TP(CD3) was taken in and hydrolyzed readily to α-T(CD3) in cultured cells and in mice. The hydrolysis of α-TP(CD3) in cell culture medium was not observed. α-TP protected primary cortical neuronal cells from glutamate-induced cytotoxicity, and α-TP given to mice reduced the levels of lipid peroxidation products in plasma and liver. These results suggest that α-TP is readily hydrolyzed in vivo to α-T, which acts as an antioxidant, and that α-TP may be used as a water-soluble α-T precursor in intravenous fluids, in eye drops, or as a dietary supplement.
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Affiliation(s)
- Keiko Nishio
- Health Research Institute, National Institute of Advanced Industrial Science & Technology, Ikeda, Osaka 563-8577, Japan
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Zingg JM, Libinaki R, Lai CQ, Meydani M, Gianello R, Ogru E, Azzi A. Modulation of gene expression by α-tocopherol and α-tocopheryl phosphate in THP-1 monocytes. Free Radic Biol Med 2010; 49:1989-2000. [PMID: 20923704 DOI: 10.1016/j.freeradbiomed.2010.09.034] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/16/2010] [Revised: 09/09/2010] [Accepted: 09/27/2010] [Indexed: 11/16/2022]
Abstract
The natural vitamin E analog α-tocopheryl phosphate (αTP) modulates atherosclerotic and inflammatory events more efficiently than the unphosphorylated α-tocopherol (αT). To investigate the molecular mechanisms involved, we have measured plasma levels of αTP and compared the cellular effects of αT and αTP in THP-1 monocytes. THP-1 cell proliferation is slightly increased by αT, whereas it is inhibited by αTP. CD36 surface expression is inhibited by αTP within hours without requiring transport of αTP into cells, suggesting that αTP may bind to CD36 and/or trigger its internalization. As assessed by gene expression microarrays, more genes are regulated by αTP than by αT. Among a set of confirmed genes, the expression of vascular endothelial growth factor is induced by αTP as a result of activating protein kinase B (PKB/Akt) and is associated with increased levels of reactive oxygen species (ROS). Increased Akt(Ser473) phosphorylation and induction of ROS by αTP occur in a wortmannin-sensitive manner, indicating the involvement of phosphatidylinositol kinases. The induction of Akt(Ser473) phosphorylation and ROS production by αTP can be attenuated by αT. It is concluded that αTP and αT influence cell proliferation, ROS production, and Akt(Ser473) phosphorylation in an antagonistic manner, most probably by modulating phosphatidylinositol kinases.
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Affiliation(s)
- Jean-Marc Zingg
- Jean Mayer USDA Human Nutrition Research Center on Aging, Tufts University, Boston, MA 02111, USA.
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Abstract
Vitamin E is known as the most important lipid antioxidant and is widely used to prevent age-associated diseases. Despite increasing knowledge about human vitamin E metabolism, little is known to justify its widespread use. As meta-analyses revealed even harmful effects of high vitamin E doses, a profound understanding of vitamin E metabolism is mandatory. By recent advances in analytical methodology, new metabolites with distinct physicochemical and biological properties were discovered. This review covers current methods to analyze vitamin E metabolites in biological samples. Special emphasis is laid on analytical applications for the identification and quantification of metabolites with a modified hydroxychromanol ring or a truncated side chain.
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Affiliation(s)
- Marc Birringer
- Department of Human Nutrition, Institute of Nutrition, Friedrich Schiller University, Jena, Germany.
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Abstract
Vitamin E is an essential fat-soluble micronutrient for higher mammals and functions as an antioxidant for lipids and also as a regulator of gene expression and a modulator of cell signaling and proliferation. To exert its physiological functions, vitamin E must achieve an appropriate disposition throughout the body via several processes, such as intestinal absorption, uptake and efflux in peripheral tissues and biliary secretion. In this review, we mainly discuss membrane proteins involved in these transport processes (ATP-binding cassette transporter A1, scavenger receptor class B type I, Niemann-Pick C1-like 1 and multidrug resistance 3) and vitamin E-mediated regulation of their expression.
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Affiliation(s)
- Tappei Takada
- Department of Pharmacy, The University of Tokyo Hospital, Faculty of Medicine, The University of Tokyo, Tokyo, Japan.
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Zingg JM, Meydani M, Azzi A. alpha-Tocopheryl phosphate--an active lipid mediator? Mol Nutr Food Res 2010; 54:679-92. [PMID: 20169583 DOI: 10.1002/mnfr.200900404] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The vitamin E (alpha-tocopherol, alphaT) derivative, alpha-tocopheryl phosphate (alphaTP), is detectable in small amounts in plasma, tissues, and cultured cells. Studies done in vitro and in vivo suggest that alphaT can become phosphorylated and alphaTP dephosphorylated, suggesting the existence of enzyme(s) with alphaT kinase or alphaTP phosphatase activity, respectively. As a supplement in animal studies, alphaTP can reach plasma concentrations similar to alphaT and only a part is dephosphorylated; thus, alphaTP may act both as pro-vitamin E, but also as phosphorylated form of vitamin E with possibly novel regulatory activities. Many effects of alphaTP have been described: in the test tube alphaTP modulates the activity of several enzymes; in cell culture alphaTP affects proliferation, apoptosis, signal transduction, and gene expression; in animal studies alphaTP prevents atherosclerosis, ischemia/reperfusion injury, and induces hippocampal long-term potentiation. At the molecular level, alphaTP may act as a cofactor for enzymes, as an active lipid mediator similar to other phosphorylated lipids, or indirectly by altering membrane characteristics such as lipid rafts, fluidity, and curvature. In this review, the molecular and cellular activities of alphaTP are examined and the possible functions of alphaTP as a natural compound, cofactor and active lipid mediator involved in signal transduction and gene expression discussed.
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Affiliation(s)
- Jean-Marc Zingg
- JM USDA-Human Nutr. Res. Ctr. On Aging, Tufts University, Boston, MA, USA
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DietaryRRR-α-tocopherol succinate attenuates lipopolysaccharide-induced inflammatory cytokines secretion in broiler chicks. Br J Nutr 2010; 104:1796-805. [DOI: 10.1017/s0007114510002801] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
The anti-inflammatory effects of two esters of α-tocopherol (α-TOH),all-rac-α-TOH acetate (dl-α-TOA) andRRR-α-TOH succinate (d-α-TOS), on broilers repeatedly challenged with lipopolysaccharide (LPS) were investigated. Three hundred and twenty 1-d-old broiler chicks were allotted into four treatment groups and fed on a control diet (30 mg/kgdl-α-TOA) or diets containing 10, 30, 50 mg/kgd-α-TOS. Half of the birds from each treatment group were challenged with 0·9 % NaCl solution or LPS (250 μg/kg body weight) at 16, 18 and 20 d of age. The results indicated that the pretreatment of birds with 50 mg/kgd-α-TOS markedly reduced serum PGE2secretion and increased the concentrations of serum or hepatic α-TOH. When LPS-challenged birds were pretreated with 30 or 50 mg/kgd-α-TOS, the increases of plasma and splenic concentrations of interferon-γ, IL-1β, IL-2, IL-6, IL-4 and IL-10 were dramatically attenuated. Also, a significant decrease of hepatic reactive oxygen species (ROS) and hepatic or splenic phosphokinase C (PKC) activities was found in birds pretreated with 30 or 50 mg/kgd-α-TOS. Furthermore,d-α-TOS inhibited the activation of NF-κB by preventing the degradation of inhibitory-κBα. In conclusion, D-α-TOS is able to prevent LPS-induced inflammation responsein vivo.The beneficial effect may depend on suppressing the secretion of various plasma and splenic inflammatory mediators through inhibiting NF-κB activation and by blocking ROS signalling, in which PKC may play an assistant role.
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Lobato KR, Cardoso CC, Binfaré RW, Budni J, Wagner CLR, Brocardo PS, de Souza LF, Brocardo C, Flesch S, Freitas AE, Dafré AL, Rodrigues ALS. alpha-Tocopherol administration produces an antidepressant-like effect in predictive animal models of depression. Behav Brain Res 2010; 209:249-59. [PMID: 20144659 DOI: 10.1016/j.bbr.2010.02.002] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2009] [Revised: 01/27/2010] [Accepted: 02/01/2010] [Indexed: 11/30/2022]
Abstract
This study investigated the antidepressant potential of alpha-tocopherol, the most active and abundant form of vitamin E, in the forced swim test (FST) and tail suspension test (TST). The acute oral treatment with alpha-tocopherol at the doses of 30 and 100mg/kg reduced the immobility time in the FST and in the TST. A single i.c.v. administration of alpha-tocopheryl phosphate, a water-soluble analogue of alpha-tocopherol, also reduced the immobility time in the FST (0.1 and 1 nmol/site) and in the TST (0.1 nmol/site). In addition, the long-term treatment (28 days) with alpha-tocopherol (10mg/kg, p.o.) significantly reduced the immobility time in the FST. Moreover, a subeffective dose of alpha-T (10mg/kg, p.o.) potentiated the effect of fluoxetine (10mg/kg, p.o.) in the FST. The long-term treatment with alpha-T was able to increase the glutathione (GSH) antioxidant defense system, while the acute treatment was not. The long-term treatment with alpha-tocopherol (10mg/kg) increased the GSH levels in the hippocampus and in the prefrontal cortex and increased the glutathione peroxidase and glutathione reductase activity in the hippocampus (10mg/kg) and in the prefrontal cortex (10-100mg/kg). The long-term treatment with fluoxetine (10mg/kg, p.o.), a positive control, was also able to increase the GSH levels in the hippocampus, but failed to alter the activity of both enzymes. Besides the specific antidepressant-like effect, long-term, but not the acute treatment with alpha-T, especially in the doses that produced an antidepressant-like effect (10mg/kg), improved the antioxidant defenses in the mouse hippocampus and prefrontal cortex, two structures closely implicated in the pathophysiology of depression.
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Affiliation(s)
- Kelly R Lobato
- Departamento de Bioquímica, Centro de Ciências Biológicas, Universidade Federal de Santa Catarina, Campus Universitário-Trindade, 88040-900 Florianópolis, SC, Brazil
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Ulrich-Merzenich G, Zeitler H, Vetter H, Kraft K. Synergy research: vitamins and secondary plant components in the maintenance of the redox-homeostasis and in cell signaling. PHYTOMEDICINE : INTERNATIONAL JOURNAL OF PHYTOTHERAPY AND PHYTOPHARMACOLOGY 2009; 16:2-16. [PMID: 19118991 DOI: 10.1016/j.phymed.2008.11.007] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2008] [Accepted: 11/20/2008] [Indexed: 05/27/2023]
Abstract
The maintenance of the redox-homeostasis is an essential task of antioxidants. Reactive oxygen species (ROS) formed during oxidative stress can potentially damage the normal cellular functions and support pathological processes like atherosclerosis in vessels or malignant growth in other tissues, but also the aging process. However, recent findings link ROS also to cell survival and/or proliferation, which revolutionises the age-old dogmatic view of ROS being exclusively involved in cell damage and death. Low concentrations of hydrogenperoxide e.g. are involved in cell signaling and can activate mitogen-activated kinases (MAPK) to initiate cell growth. Nutritional antioxidants like vitamin C or E can promote endothelial cell growth, but can also inhibit growth of muscle cells, and influence MAPK. Thus, keeping the redox-homeostasis in a steady state especially in the context of tissue regeneration appears to be more important than previously known and seems to be a controlled synergistic action of antioxidants and ROS. The present review summarizes the properties and functions of ROS and nutritional antioxidants like the vitamins C and E, and polyphenols in redox-homeostasis. Their relevance in the treatment of various diseases is discussed in the context of a multitarget therapy with nutraceuticals and phytotherapeutic drugs.
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Zingg JM, Azzi A, Meydani M. Genetic polymorphisms as determinants for disease-preventive effects of vitamin E. Nutr Rev 2008; 66:406-14. [DOI: 10.1111/j.1753-4887.2008.00050.x] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
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Mukherjee S, Lekli I, Das M, Azzi A, Das DK. Cardioprotection with alpha-tocopheryl phosphate: amelioration of myocardial ischemia reperfusion injury is linked with its ability to generate a survival signal through Akt activation. Biochim Biophys Acta Mol Basis Dis 2008; 1782:498-503. [PMID: 18555028 DOI: 10.1016/j.bbadis.2008.05.002] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2008] [Revised: 05/05/2008] [Accepted: 05/06/2008] [Indexed: 02/07/2023]
Abstract
The emerging potential of alpha-tocopheryl phosphate, a phosphoric acid ester of alpha-tocopherol, in health benefits was tested gavaging this compound (5 mg/kg body wt) to a group of rats for a period of thirty days while the control rats were given water only. After thirty days, the rats were sacrificed, the hearts excised, and the isolated hearts were perfused by working mode. Both control and experimental hearts were subjected to 30-min global ischemia followed by 2 h of reperfusion. The tocopheryl phosphate fed rats exhibited significant cardioprotection as evidenced by improved ventricular performance and reduced myocardial infarct size and cardiomyocyte apoptosis. Supplementation with alpha-tocopheryl phosphate converted MAP kinase-induced death signal into a survival signal by enhancing anti-apoptotic p42/44 ERK kinase and p38 MAPKbeta and reducing pro-apoptotic proteins p38 MAPKalpha and JNK. In concert, the phosphorylation of pro-apoptotic c-Src was also reduced. Tocopheryl phosphate increased the DNA binding of the redox-sensitive transcription factor NFkappaB and potentiated the activation of anti-death protein Bcl-2 and survival signaling protein Akt. The results of this study demonstrated for the first time that tocopheryl phosphate could ameliorate myocardial ischemic reperfusion injury by converting ischemia/reperfusion-mediated death signal into a survival signal by modulating MAP kinase signaling.
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Affiliation(s)
- Subhendu Mukherjee
- Cardiovascular Research Center, University of Connecticut School of Medicine, Farmington, CT 06030-1110, USA
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Ito S, Mori T, Kanazawa H, Sawaguchi T. Differential effects of the ascorbyl and tocopheryl derivative on the methamphetamine-induced toxic behavior and toxicity. Toxicology 2007; 240:96-110. [PMID: 17875351 DOI: 10.1016/j.tox.2007.07.022] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2007] [Revised: 07/24/2007] [Accepted: 07/25/2007] [Indexed: 01/24/2023]
Abstract
A previous study showed that high doses of methamphetamine induce self-injurious behavior (SIB) in rodents. Furthermore, the combination of methamphetamine and morphine increased lethality in mice. We recently surmised that the rise in SIB and mortality induced by methamphetamine and/or morphine may be related to oxidative stress. The present study was designed to determine whether an antioxidant could inhibit SIB or mortality directly induced by methamphetamine and/or morphine. The SIB induced by 20mg/kg of methamphetamine was abolished by the administration of Na L-ascorbyl-2-phosphate (APS: 300 mg/kg), but not Na DL-alpha-tocopheryl phosphate (TPNa: 200mg/kg). In contrast, APS (300 mg/kg) and TPNa (200mg/kg) each significantly attenuated the lethality induced by methamphetamine and morphine. The present study showed that the signal intensity of superoxide adduct was increased by 20mg/kg of methamphetamine in the heart and lungs, and methamphetamine plus morphine tended to increase superoxide adduct in all of the tissues measured by ESR spin trap methods. Adduct signal induced in brain by methamphetamine administration increased in significance, but in mouse administrated methamphetamine plus morphine. There are differential effects of administration of methamphetamine and coadministration of methamphetamine plus morphine on adduct signal. These results suggest that APS and TPNa are effective for reducing methamphetamine-induced toxicity and/or toxicological behavior. While APS and TPNa each affected methamphetamine- and/or morphine-induced toxicology and/or toxicological behavior, indicating that both drugs have antioxidative effects, their effects differed.
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Affiliation(s)
- Shinobu Ito
- Department of Legal Medicine, Tokyo Women's Medical University, 8-1 Kawada-cho, Shinjuku-ku, Tokyo 162-8666, Japan
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Zingg JM. Vitamin E: An overview of major research directions. Mol Aspects Med 2007; 28:400-22. [PMID: 17624418 DOI: 10.1016/j.mam.2007.05.004] [Citation(s) in RCA: 116] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2007] [Accepted: 05/23/2007] [Indexed: 02/07/2023]
Abstract
During the last 90 years since the discovery of vitamin E, research has focused on different properties of this molecule, the focus often depending on the specific techniques and scientific knowledge present at each time. Originally discovered as a dietary factor essential for reproduction in rats, vitamin E has revealed in the meantime many more important molecular properties, such as the scavenging of reactive oxygen and nitrogen species with consequent prevention of oxidative damage associated with many diseases, or the modulation of signal transduction and gene expression in antioxidant and non-antioxidant manners. Research over the last 30 years has also resolved the biosynthesis and occurrence of vitamin E in plants, the proteins involved in the cellular uptake, tissue distribution and metabolism, and defined a congenital recessive neurological disease, ataxia with vitamin E deficiency (AVED), characterized by impaired enrichment of alpha-tocopherol in plasma as a result of mutations in the liver alpha-tocopherol transfer gene. This review is giving a brief introduction about vitamin E by following the major research directions since its discovery with a historical perspective.
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Affiliation(s)
- Jean-Marc Zingg
- Institute of Biochemistry and Molecular Medicine, University of Bern, Bühlstrasse 28, 3012 Bern, Switzerland.
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Munteanu A, Zingg JM. Cellular, molecular and clinical aspects of vitamin E on atherosclerosis prevention. Mol Aspects Med 2007; 28:538-90. [PMID: 17825403 DOI: 10.1016/j.mam.2007.07.001] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2007] [Accepted: 07/23/2007] [Indexed: 02/07/2023]
Abstract
Randomised clinical trials and epidemiologic studies addressing the preventive effects of vitamin E supplementation against cardiovascular disease reported both positive and negative effects, and recent meta-analyses of the clinical studies were rather disappointing. In contrast to that, many animal studies clearly show a preventive action of vitamin E in several experimental settings, which can be explained by the molecular and cellular effects of vitamin E observed in cell cultures. This review is focusing on the molecular effects of vitamin E on the cells playing a role during atherosclerosis, in particular on the endothelial cells, vascular smooth muscle cells, monocytes/macrophages, T cells, and mast cells. Vitamin E may act by normalizing aberrant signal transduction and gene expression in antioxidant and non-antioxidant manners; in particular, over-expression of scavenger receptors and consequent foam cell formation can be prevented by vitamin E. In addition to that, the cellular effects of alpha-tocopheryl phosphate and of EPC-K1, a composite molecule between alpha-tocopheryl phosphate and l-ascorbic acid, are summarized.
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Affiliation(s)
- Adelina Munteanu
- Physiology Department, Faculty of Medicine, University of Medicine and Pharmacy Bucharest, Romania
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Negis Y, Meydani M, Zingg JM, Azzi A. Molecular mechanism of α-tocopheryl-phosphate transport across the cell membrane. Biochem Biophys Res Commun 2007; 359:348-53. [PMID: 17537406 DOI: 10.1016/j.bbrc.2007.05.094] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2007] [Accepted: 05/15/2007] [Indexed: 01/08/2023]
Abstract
alpha-Tocopheryl-phosphate (alpha-TP) is synthesized and hydrolyzed in animal cells and tissues where it modulates several functions. alpha-TP is more potent than alpha-T in inhibiting cell proliferation, down-regulating CD36 transcription, inhibiting atherosclerotic plaque formation. Administration of alpha-TP to cells or animals requires its transfer through membranes, via a transporter. We show here that alpha-TP is passing the plasma membrane via a system that is inhibited by glibenclamide and probenecid, inhibitors of a number of transporters. Glibenclamide and probenecid prevent dose-dependently alpha-TP inhibition of cell proliferation. The two inhibitors act on ATP binding cassette (ABC) and organic anion transporters (OAT). Since ABC transporters function to export solutes and alpha-TP is transported into cells, it may be concluded that alpha-TP transport may occur via an OAT family member. Due to the protection by glibenclamide and probenecid on the alpha-TP induced cell growth inhibition it appears that alpha-TP acts after its uptake inside cells.
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Affiliation(s)
- Yesim Negis
- Vascular Biology Laboratory, The Jean Mayer USDA Human Nutrition Center at Tufts University, Boston, MA 02111, USA
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Azzi A. Molecular mechanism of alpha-tocopherol action. Free Radic Biol Med 2007; 43:16-21. [PMID: 17561089 DOI: 10.1016/j.freeradbiomed.2007.03.013] [Citation(s) in RCA: 241] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/19/2006] [Revised: 03/01/2007] [Accepted: 03/19/2007] [Indexed: 12/22/2022]
Abstract
The inability of other antioxidants to substitute for alpha-tocopherol in a number of cellular reactions, the lack of a compensatory antioxidant response in the gene expression under conditions of alpha-tocopherol deficiency, the unique uptake of alpha-tocopherol relative to the other tocopherols and its slower catabolism, and the striking differences in the molecular function of the different tocopherols and tocotrienols, observed in vitro, unrelated to their antioxidant properties, are all data in support of a nonantioxidant molecular function of alpha-tocopherol. Furthermore, in vivo studies have also shown that alpha-tocopherol is not able, at physiological concentrations, to protect against oxidant-induced damage or prevent disease allegedly caused by oxidative damage. Alpha-tocopherol appears to act as a ligand of not yet identified specific proteins (receptors, transcription factors) capable of regulating signal transduction and gene expression.
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Affiliation(s)
- Angelo Azzi
- Vascular Biology Laboratory, Office 622, JM USDA-HNRCA at Tufts University, 711 Washington Street, Boston, MA 02111, USA.
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Neuzil J, Tomasetti M, Zhao Y, Dong LF, Birringer M, Wang XF, Low P, Wu K, Salvatore BA, Ralph SJ. Vitamin E analogs, a novel group of "mitocans," as anticancer agents: the importance of being redox-silent. Mol Pharmacol 2007; 71:1185-99. [PMID: 17220355 DOI: 10.1124/mol.106.030122] [Citation(s) in RCA: 111] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
The search for a selective and efficient anticancer agent for treating all neoplastic disease has yet to deliver a universally suitable compound(s). The majority of established anticancer drugs either are nonselective or lose their efficacy because of the constant mutational changes of malignant cells. Until recently, a largely neglected target for potential anticancer agents was the mitochondrion, showing a considerable promise for future clinical applications. Vitamin E (VE) analogs, epitomized by alpha-tocopheryl succinate, belong to the group of "mitocans" (mitochondrially targeted anticancer drugs). They are selective for malignant cells, cause destabilization of their mitochondria, and suppress cancer in preclinical models. This review focuses on our current understanding of VE analogs in the context of their proapoptotic/anticancer efficacy and suggests that their effect on mitochondria may be amplified by modulation of alternative pathways operating in parallel. We show here that the analogs of VE that cause apoptosis (which translates into their anticancer efficacy) generally do not possess antioxidant (redox) activity and are prototypical of the mitocan group of anticancer compounds. Therefore, by analogy to Oscar Wilde's play The Importance of Being Earnest, we use the motto in the title "the importance of being redox-silent" to emphasize an essentially novel paradigm for cancer therapy, in which redox-silence is a prerequisite property for most of the anticancer activities described in this communication.
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Affiliation(s)
- Jiri Neuzil
- Apoptosis Research Group, Heart Foundation Research Centre, School of Medical Science, Griffith University Gold Coast Campus, Southport, Queensland, Australia.
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Libinaki R, Ogru E, Gianello R, Bolton L, Geytenbeek S. Evaluation of the safety of mixed tocopheryl phosphates (MTP)—A formulation of α-tocopheryl phosphate plus α-di-tocopheryl phosphate. Food Chem Toxicol 2006; 44:916-32. [PMID: 16337325 DOI: 10.1016/j.fct.2005.10.013] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2005] [Revised: 10/04/2005] [Accepted: 10/22/2005] [Indexed: 11/28/2022]
Abstract
The safety of a formulation of mixed tocopheryl phosphates, (MTP) was evaluated in a series of toxicological tests in vivo using rats, mice and rabbits and in vitro using bacterial and mammalian cell cultures. The tests conducted included an oral LD(50) study, three 28-day oral repeat-dose studies, two dermal toxicity tests, an ocular irritation test, mutagenic potential tests, and chromosomal aberrations tests. MTP consists of mono alpha-tocopheryl phosphate (TP) and di-tocopheryl phosphate (T(2)P) and is intended for use as a dietary supplement and for dermal applications in humans and animals. The dermal and oral LD(50) values of MTP were determined to be >1130 mg/kg bw (918 mg tocopherol equivalents/kg bw) in rabbits and rats, respectively. MTP was not a dermal or eye irritant in rabbits and showed no allergenic potential in mice. In the mutagenicity and genotoxicity studies, MTP did not increased the number of revertants in Salmonella typhimurium or Escherichia coli and did not induce chromosomal aberrations in cultured Chinese hamster ovary (CHO) cells. When administered daily for 28 days by gavage at doses up to 955 mg/kg bw/day (780 mg tocopherol equivalents/kg bw/day), MTP produced no consistent, dose-dependent adverse effects in rats.
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Affiliation(s)
- R Libinaki
- Department of Biochemistry and Molecular Biology, Monash University, Building 13D, Melbourne 3800, Australia
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Negis Y, Aytan N, Ozer N, Ogru E, Libinaki R, Gianello R, Azzi A, Zingg JM. The effect of tocopheryl phosphates on atherosclerosis progression in rabbits fed with a high cholesterol diet. Arch Biochem Biophys 2006; 450:63-6. [PMID: 16579956 DOI: 10.1016/j.abb.2006.02.027] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2006] [Revised: 02/13/2006] [Accepted: 02/16/2006] [Indexed: 11/18/2022]
Abstract
The effect of tocopheryl phosphate on atherosclerosis progression has been studied in rabbits, fed with a 2% cholesterol diet and compared with an equivalent amount of alpha-tocopheryl acetate. The results show that the atherosclerotic-preventing effect of the phosphate derivative was more pronounced than that of the acetate derivative. alpha-Tocopheryl phosphate was also more potent in diminishing the expression of CD36 than the acetate derivative.
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Affiliation(s)
- Yesim Negis
- Department of Biochemistry, Faculty of Medicine, Marmara University, 81326 Haydarpasa, Istanbul, Turkey
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Frank J, Teresa SDP, Rimbach G. Nutrigenomics ? new frontiers in antioxidant research. ACTA ACUST UNITED AC 2006. [DOI: 10.1616/1476-2137.14276] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Gianello R, Libinaki R, Azzi A, Gavin PD, Negis Y, Zingg JM, Holt P, Keah HH, Griffey A, Smallridge A, West SM, Ogru E. Alpha-tocopheryl phosphate: a novel, natural form of vitamin E. Free Radic Biol Med 2005; 39:970-6. [PMID: 16140216 DOI: 10.1016/j.freeradbiomed.2005.05.016] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/15/2005] [Revised: 05/12/2005] [Accepted: 05/12/2005] [Indexed: 10/25/2022]
Abstract
We have detected alpha-tocopheryl phosphate in biological tissues including liver and adipose tissue, as well as in a variety of foods, suggesting a ubiquitous presence in animal and plant tissue. Alpha-tocopheryl phosphate is a water-soluble molecule that is resistant to both acid and alkaline hydrolysis, making it undetectable using standard assays for vitamin E. A new method was therefore developed to allow the extraction of both alpha-tocopheryl phosphate and alpha-tocopherol from a single specimen. We used ESMS to detect endogenous alpha-tocopheryl phosphate in biological samples that also contained alpha-tocopherol. Due to the significance of these findings, further proof was required to unequivocally demonstrate the presence of endogenous alpha-tocopheryl phosphate in biological samples. Four independent methods of analysis were examined: HPLC, LCMS, LCMS/MS, and GCMS. Alpha-tocopherol phosphate was identified in all instances by comparison between standard alpha-tocopheryl phosphate and extracts of biological tissues. The results show that alpha-tocopheryl phosphate is a natural form of vitamin E. The discovery of endogenous alpha-tocopheryl phosphate has implications for the expanding knowledge of the roles of alpha-tocopherol in biological systems.
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Affiliation(s)
- Robert Gianello
- Department of Biochemistry and Molecular Biology, Monash University, Clayton 3800, Australia
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Azzi A, Zingg JM. Vitamin E: Textbooks require updating. BIOCHEMISTRY AND MOLECULAR BIOLOGY EDUCATION : A BIMONTHLY PUBLICATION OF THE INTERNATIONAL UNION OF BIOCHEMISTRY AND MOLECULAR BIOLOGY 2005; 33:184-187. [PMID: 21638573 DOI: 10.1002/bmb.2005.494033032451] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Vitamin E was discovered in 1922, but in more than 60 years many new findings have added to the early one. However, its description in many textbooks has not been proportionally updated. The result is an inaccurate, incomplete, and often incorrect description of the function of this vitamin. In some other textbooks, vitamin E is absolutely neglected. In almost all books the existence of vitamin E deficiency diseases is ignored. Recent findings on vitamin E molecular functions and its related diseases are described in this article.
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Affiliation(s)
- Angelo Azzi
- Institute of Biochemistry and Molecular Biology, University of Bern, 3012 Bern, Switzerland.
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