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Journal of Agricultural and Food... Jan 2018δ-Tocopherol (δ-TOH) is a form of vitamin E with higher bioactivity. In this study, we studied the bioactivity of δ-TOH using the IC of δ-TOH on RAW264.7 (80 μM)...
δ-Tocopherol (δ-TOH) is a form of vitamin E with higher bioactivity. In this study, we studied the bioactivity of δ-TOH using the IC of δ-TOH on RAW264.7 (80 μM) and K562 (110 μM) cells. We compared the differential metabolites from the cell lines with and without δ-TOH treatment by H NMR metabonomics analysis. It was found that δ-TOH affected the protein biosynthesis, betaine metabolism, and urea cycle in various ways in both cell lines. Metabolic levels of the cell lines were changed after treatment with δ-TOH as differential metabolites were produced. The betaine level in RAW264.7 cells was reduced significantly, while the l-lactic acid level in K562 cells was significantly enhanced. The metabolic changes might contribute to the switch of the respiration pattern from aerobic respiration to anaerobic respiration in K562 cells. These results are helpful in further understanding the subtoxicity of δ-TOH.
Topics: Animals; Betaine; Humans; K562 Cells; Lactic Acid; Macrophages; Magnetic Resonance Spectroscopy; Metabolic Networks and Pathways; Metabolomics; Mice; Protein Biosynthesis; Proteins; RAW 264.7 Cells; Tocopherols; Urea
PubMed: 29313349
DOI: 10.1021/acs.jafc.7b04667 -
Plant Physiology Nov 2019Tocopherols are lipid-soluble antioxidants synthesized in plastids of plants and other photosynthetic organisms. The four known tocopherols, α-, β-, γ-, and...
Tocopherols are lipid-soluble antioxidants synthesized in plastids of plants and other photosynthetic organisms. The four known tocopherols, α-, β-, γ-, and δ-tocopherol, differ in number and position of methyl groups on their chromanol head group. In unstressed Arabidopsis () leaves, α-tocopherol constitutes the main tocopherol form, whereas seeds predominantly contain γ-tocopherol. Here, we show that inoculation of Arabidopsis leaves with the bacterial pathogen induces the expression of genes involved in early steps of tocopherol biosynthesis and triggers strong accumulation of γ-tocopherol, moderate production of δ-tocopherol, and generation of the benzoquinol precursors of tocopherols. The pathogen-inducible biosynthesis of tocopherols is promoted by the immune regulators ENHANCED DISEASE SUSCEPTIBILITY1 and PHYTOALEXIN-DEFICIENT4. In addition, tocopherols accumulate in response to bacterial flagellin and reactive oxygen species. By quantifying tocopherol forms in inoculated wild-type plants and biosynthetic pathway mutants, we provide biochemical insights into the pathogen-inducible tocopherol pathway. Notably, () mutant plants, which are compromised in both tocopherol and benzoquinol precursor accumulation, exhibit increased susceptibility toward compatible and possess heightened levels of markers of lipid peroxidation after bacterial infection. The deficiency of triunsaturated fatty acids in () quadruple mutants prevents increased lipid peroxidation in the background and restores pathogen resistance to wild-type levels. Therefore, the tocopherol biosynthetic pathway positively influences salicylic acid accumulation and guarantees effective basal resistance of Arabidopsis against compatible , possibly by protecting leaves from the pathogen-induced oxidation of trienoic fatty acid-containing lipids.
Topics: Arabidopsis; Arabidopsis Proteins; Carboxylic Ester Hydrolases; DNA-Binding Proteins; Gene Expression Regulation, Plant; Plant Immunity; Plant Leaves; Pseudomonas syringae; Tocopherols
PubMed: 31515446
DOI: 10.1104/pp.19.00618 -
Life Sciences Mar 2006In nature, eight substances have been found to have vitamin E activity: alpha-, beta-, gamma- and delta-tocopherol; and alpha-, beta-, gamma- and delta-tocotrienol. Yet,... (Review)
Review
In nature, eight substances have been found to have vitamin E activity: alpha-, beta-, gamma- and delta-tocopherol; and alpha-, beta-, gamma- and delta-tocotrienol. Yet, of all papers on vitamin E listed in PubMed less than 1% relate to tocotrienols. The abundance of alpha-tocopherol in the human body and the comparable efficiency of all vitamin E molecules as antioxidants, led biologists to neglect the non-tocopherol vitamin E molecules as topics for basic and clinical research. Recent developments warrant a serious reconsideration of this conventional wisdom. Tocotrienols possess powerful neuroprotective, anti-cancer and cholesterol lowering properties that are often not exhibited by tocopherols. Current developments in vitamin E research clearly indicate that members of the vitamin E family are not redundant with respect to their biological functions. alpha-Tocotrienol, gamma-tocopherol, and delta-tocotrienol have emerged as vitamin E molecules with functions in health and disease that are clearly distinct from that of alpha-tocopherol. At nanomolar concentration, alpha-tocotrienol, not alpha-tocopherol, prevents neurodegeneration. On a concentration basis, this finding represents the most potent of all biological functions exhibited by any natural vitamin E molecule. An expanding body of evidence support that members of the vitamin E family are functionally unique. In recognition of this fact, title claims in manuscripts should be limited to the specific form of vitamin E studied. For example, evidence for toxicity of a specific form of tocopherol in excess may not be used to conclude that high-dosage "vitamin E" supplementation may increase all-cause mortality. Such conclusion incorrectly implies that tocotrienols are toxic as well under conditions where tocotrienols were not even considered. The current state of knowledge warrants strategic investment into the lesser known forms of vitamin E. This will enable prudent selection of the appropriate vitamin E molecule for studies addressing a specific need.
Topics: Animals; Antioxidants; Humans; Tocotrienols; Vitamin E
PubMed: 16458936
DOI: 10.1016/j.lfs.2005.12.001 -
Plants (Basel, Switzerland) Nov 2021In vitro cultures have been used as an effective means to achieve a high level of secondary metabolites in various plants, including soy. In this study, the contents of...
In vitro cultures have been used as an effective means to achieve a high level of secondary metabolites in various plants, including soy. In this study, the contents of α-, γ-, and δ- tocopherol were quantified in soybean callus, and their amounts were compared to those of soybeans cultivated using the conventional tillage system with three weed controls (respectively without herbicide and with two variants of herbicide). Soybean callus was produced using Murashige and Skoog 1962 (MS) medium supplemented with 0.1 mg/L 6-Benzylaminopurine (BAP) and 0. 1 mg/L Thidiazuron (TDZ). The highest amount of fresh callus was obtained from soybeans from the conventional tillage system with second weed control (S-metolachlor 960 g/L, imazamox 40 g/L, and propaquizafop 100 g/L) respectively 13,652.4 ± 1177.62 mg. The analyzed tocopherols were in much higher content in soy dry callus than the soybean seeds (5.63 µg/g compared with the 0.35 α-toco in soybean, 47.57 µg/g compared with 18.71 µg/g γ-toco or, 5.56 µg/g compared with 1.74 µg/g β-toco). The highest content of the three analyzed tocopherols was γ -tocopherol, both in callus and soybeans. Furthermore, the data showed that herbicides used in soybean culture significantly influenced both the in vitro callus production and the tocopherol callus content ( ˂ 0.05). Altogether, soybean callus can be an important source of tocopherols, and herbicides significantly influence in vitro callus production and the tocopherol callus content.
PubMed: 34961042
DOI: 10.3390/plants10122571 -
Nutrition & Metabolism 2014Tocotrienols, members of the vitamin E family, are natural compounds found in a number of vegetable oils, wheat germ, barley, and certain types of nuts and grains. Like... (Review)
Review
Tocotrienols, members of the vitamin E family, are natural compounds found in a number of vegetable oils, wheat germ, barley, and certain types of nuts and grains. Like tocopherols, tocotrienols are also of four types viz. alpha, beta, gamma and delta. Unlike tocopherols, tocotrienols are unsaturated and possess an isoprenoid side chain. Tocopherols are lipophilic in nature and are found in association with lipoproteins, fat deposits and cellular membranes and protect the polyunsaturated fatty acids from peroxidation reactions. The unsaturated chain of tocotrienol allows an efficient penetration into tissues that have saturated fatty layers such as the brain and liver. Recent mechanistic studies indicate that other forms of vitamin E, such as γ-tocopherol, δ-tocopherol, and γ-tocotrienol, have unique antioxidant and anti-inflammatory properties that are superior to those of α-tocopherol against chronic diseases. These forms scavenge reactive nitrogen species, inhibit cyclooxygenase- and 5-lipoxygenase-catalyzed eicosanoids and suppress proinflammatory signalling, such as NF-κB and STAT. The animal and human studies show tocotrienols may be useful against inflammation-associated diseases. Many of the functions of tocotrienols are related to its antioxidant properties and its varied effects are due to it behaving as a signalling molecule. Tocotrienols exhibit biological activities that are also exhibited by tocopherols, such as neuroprotective, anti-cancer, anti-inflammatory and cholesterol lowering properties. Hence, effort has been made to compile the different functions and properties of tocotrienols in experimental model systems and humans. This article constitutes an in-depth review of the pharmacology, metabolism, toxicology and biosafety aspects of tocotrienols. Tocotrienols are detectable at appreciable levels in the plasma after supplementations. However, there is inadequate data on the plasma concentrations of tocotrienols that are sufficient to demonstrate significant physiological effect and biodistribution studies show their accumulation in vital organs of the body. Considering the wide range of benefits that tocotrienols possesses against some common human ailments and having a promising potential, the experimental analysis accounts for about a small fraction of all vitamin E research. The current state of knowledge deserves further investigation into this lesser known form of vitamin E.
PubMed: 25435896
DOI: 10.1186/1743-7075-11-52 -
Food Chemistry Nov 2017A normal-phase high performance liquid chromatography method for the simultaneous determination of tert-butylhydroquinone, tert-butylquinone, butylated hydroxytoluene,...
Simultaneous analysis of tert-butylhydroquinone, tert-butylquinone, butylated hydroxytoluene, 2-tert-butyl-4-hydroxyanisole, 3-tert-butyl-4-hydroxyanisole, α-tocopherol, γ-tocopherol, and δ-tocopherol in edible oils by normal-phase high performance liquid chromatography.
A normal-phase high performance liquid chromatography method for the simultaneous determination of tert-butylhydroquinone, tert-butylquinone, butylated hydroxytoluene, 2-tert-butyl-4-hydroxyanisole, 3-tert-butyl-4-hydroxyanisole, α-tocopherol, γ-tocopherol, and δ-tocopherol in edible oils was investigated. A silica column was used to separate the analytes with the gradient elution. An ultraviolet-visible detector was set at dual wavelengths mode (280 and 310nm). The column temperature was 30°C. The analytes were directly extracted with methanol. Results showed that the normal-phase high performance liquid chromatography method performed well with wide liner ranges (0.10∼500.00μg/mL, R>0.9998), low limits of detection and quantitation (below 0.40 and 1.21μg/mL, respectively), and good recoveries (81.38∼102.34% in soybean oils and 83.03∼100.79% in lard, respectively). The reduction of tert-butylquinone caused by the reverse-phase high performance liquid chromatography during the injection was avoided with the current normal-phase method. The two isomers of butylated hydroxyanisole can also be separated with good resolution.
Topics: Butylated Hydroxyanisole; Butylated Hydroxytoluene; Chromatography, High Pressure Liquid; Food Analysis; Plant Oils; Quinones; Tocopherols
PubMed: 28551227
DOI: 10.1016/j.foodchem.2017.04.176 -
Cancer Prevention Research... Mar 2017Estrogens have been implicated as complete carcinogens for breast and other tissues through mechanisms involving increased cell proliferation, oxidative stress, and DNA...
Estrogens have been implicated as complete carcinogens for breast and other tissues through mechanisms involving increased cell proliferation, oxidative stress, and DNA damage. Because of their potent antioxidant activity and other effects, tocopherols have been shown to exert antitumor activities in various cancers. However, limited information is available on the effect of different forms of tocopherols in estrogen-mediated breast cancer. To address this, we examined the effects of α-, γ-, and δ-tocopherols as well as a natural γ-tocopherol-rich mixture of tocopherols, γ-TmT, on estrogen-stimulated MCF-7 cells and For the studies, MCF-7 cells were injected into the mammary fat pad of immunodeficient mice previously implanted with estrogen pellets. Mice were then administered diets containing 0.2% α-, γ-, δ-tocopherol, or γ-TmT for 5 weeks. Treatment with α-, γ-, δ-tocopherols, and γ-TmT reduced tumor volumes by 29% ( < 0.05), 45% ( < 0.05), 41% ( < 0.05), and 58% ( < 0.01), as well as tumor weights by 20%, 37% ( < 0.05), 39% ( < 0.05), and 52% ( < 0.05), respectively. γ- and δ-tocopherols and γ-TmT inhibited the expression of cell proliferation-related genes such as cyclin D1 and c-Myc, and estrogen-related genes such as TFF/pS2, cathepsin D, and progesterone receptor in estrogen-stimulated MCF-7 cells Further, γ- and δ-tocopherols decreased the levels of estrogen-induced oxidative stress and nitrosative stress markers, 8-hydroxy-2'-deoxyguanosine and nitrotyrosine, as well as the DNA damage marker, γ-H2AX. Our results suggest that γ- and δ-tocopherols and the γ-tocopherol-rich mixture are effective natural agents for the prevention and treatment of estrogen-mediated breast cancer. .
Topics: Animals; Antioxidants; Breast Neoplasms; Cell Proliferation; Estrogens; Female; Humans; MCF-7 Cells; Mice, Nude; Oxidative Stress; Tocopherols; Xenograft Model Antitumor Assays; gamma-Tocopherol
PubMed: 28096236
DOI: 10.1158/1940-6207.CAPR-16-0223 -
Antioxidants (Basel, Switzerland) Dec 2021Scavenging of superoxide radical anion (O) by tocopherols (TOH) and related compounds was investigated on the basis of cyclic voltammetry and in situ electrolytic...
Electrochemical and Mechanistic Study of Reactivities of α-, β-, γ-, and δ-Tocopherol toward Electrogenerated Superoxide in ,-Dimethylformamide through Proton-Coupled Electron Transfer.
Scavenging of superoxide radical anion (O) by tocopherols (TOH) and related compounds was investigated on the basis of cyclic voltammetry and in situ electrolytic electron spin resonance spectrum in ,-dimethylformamide (DMF) with the aid of density functional theory (DFT) calculations. Quasi-reversible dioxygen/O redox was modified by the presence of TOH, suggesting that the electrogenerated O was scavenged by α-, β-, γ-TOH through proton-coupled electron transfer (PCET), but not by δ-TOH. The reactivities of α-, β-, γ-, and δ-TOH toward O characterized by the methyl group on the 6-chromanol ring was experimentally confirmed, where the methyl group promotes the PCET mechanism. Furthermore, comparative analyses using some related compounds suggested that the -oxygen-atom in the 6-chromanol ring is required for a successful electron transfer (ET) to O through the PCET. The electrochemical and DFT results in dehydrated DMF suggested that the PCET mechanism involves the preceding proton transfer (PT) forming a hydroperoxyl radical, followed by a PCET (intermolecular ET-PT). The O scavenging by TOH proceeds efficiently along the PCET mechanism involving one ET and two PTs.
PubMed: 35052513
DOI: 10.3390/antiox11010009 -
Plants (Basel, Switzerland) Mar 2023The seeds of 111 sp. different fruit use (dessert and cider apples) cultivars/genotypes developed in 18 countries were analysed to evaluate composition of tocopherol...
The seeds of 111 sp. different fruit use (dessert and cider apples) cultivars/genotypes developed in 18 countries were analysed to evaluate composition of tocopherol homologues and identify crop-specific profile, including diploid, triploid, and tetraploid apple cultivars with and without scab-resistance to ensure high genetic diversity. The percentage of individual tocopherols was as follows: alpha-tocopherol (alpha-T) (38.36%), beta-tocopherol (beta-T) (40.74%), gamma-tocopherol (gamma-T) (10.93%), and delta-tocopherol (delta-T) (9.97%), represented by average measurements of 17.48, 18.56, 4.98, and 4.54 mg/100 g dry weight, respectively. The values of the variation coefficient showed high variability for delta (0.695) and gamma (0.662) homologue content, whereas measurements of alpha-T and beta-T were less variable (coefficient of variation 0.203 and 0.256, respectively). The unweighted pair group method with arithmetic mean (UPGMA) revealed three main cultivar groups characterised by almost equal content of all four tocopherol homologues (Group I), high concentrations of alpha-T and beta-T, but very low content of gamma-T and delta-T (Group II), and relatively high average content of alpha-T and beta-T, but higher gamma-T and delta-T content (Group III). Specific tocopherol homologues showed association with certain valuable traits, such as harvesting time (total content of tocopherols) and resistance to apple scab (alpha-T and total content of tocopherols). This study represents the first large-scale tocopherol homologue (alpha, beta, gamma, and delta) screening in apple seeds. The dominant tocopherol homologues in cultivated apple cultivars are alpha-T and beta-T, with the prevalence of alpha-T or beta-T depending on genotype. It is a unique finding due to the rare occurrence of beta-T in the plant world and is considered a unique feature of the species.
PubMed: 36904029
DOI: 10.3390/plants12051169 -
Journal of Agricultural and Food... Jan 2008The reaction rates ( k s) of tocopherol metabolites (alpha-, gamma-, and delta-CEHC) and Trolox with aroxyl radical have been measured in ethanol and micellar solution...
Kinetic studies of the free radical-scavenging actions of tocopherol metabolites (alpha-, gamma-, and delta-carboxyethyl-6-hydroxychroman) and Trolox in ethanol and micellar solutions.
The reaction rates ( k s) of tocopherol metabolites (alpha-, gamma-, and delta-CEHC) and Trolox with aroxyl radical have been measured in ethanol and micellar solution by a stopped-flow spectrophotometer, and the k s values obtained were compared with those reported for tocopherols (alpha-, beta-, gamma-, and delta-tocopherol, TocH) and tocol. The rate constants ( k s) increased in the order of Tocol < delta-CEHC < delta-TocH < gamma-CEHC < Trolox approximately gamma-TocH approximately beta-TocH < alpha-CEHC < alpha-TocH in ethanol. The antioxidants that have lower oxidation potentials ( E p) showed higher reactivities. The k s values of alpha-, beta-, gamma-, and delta-tocopherol and tocol in micelle remained constant between pH 4 and pH 10 and decreased rapidly at pH 11~12 by increasing pH value. On the other hand, the k s values of alpha-CEHC, gamma-CEHC, and Trolox showed notable pH dependence. As a result of the detailed analysis of the pH dependence of the rate constants ( k s), the structure-activity relationship in the free radical-scavenging action of the tocopherol metabolites and Trolox has been clarified.
Topics: Chromans; Ethanol; Free Radical Scavengers; Kinetics; Micelles; Solutions; Spectrophotometry; Tocopherols
PubMed: 18069790
DOI: 10.1021/jf0720133