Disease relevance of C14151

• Neither in the volunteers nor in the patients with acute respiratory failure were there any detectable amounts of beta-, gamma- or delta-tocopherol or of alpha-tocopherolquinone or alpha-tocotrienol [1].
• Results showed that administration of commercially available propofol provoked a time- and dose-dependent increment in serum gamma-tocopherol and delta-tocopherol in control animals and in the group receiving lungs subjected to 3 h of ischemia, but not in the group with 24 h of ischemia [2].
• At 1 microM, the delta-tocopherol efficiency in inhibiting radical-induced red blood cell hemolysis was three times as high as the alpha-tocopherol efficiency [3].

High impact information on C14151

• Vitamin E is present in plants in 8 different forms with more or less equal antioxidant potential (alpha-, beta-, gamma-, delta-tocopherol/tocotrienols); nevertheless, in higher organisms only alpha-tocopherol is preferentially retained suggesting a specific mechanism for the uptake for this analogue [4].
• In contrast, analogous metabolites of gamma and delta-tocopherol were detectable without any preconditioning, while corresponding metabolites of RRR-alpha-tocopherol could not be detected at all [5].
• The detection limit was at least 25-fold lower (0.004 mg/L) when fluorometry was used for measurement of delta-, gamma-, and alpha-tocotrienol and delta-tocopherol compared with ultraviolet detection [6].
• alpha- and delta-tocopherol induce expression of hepatic alpha-tocopherol-transfer-protein mRNA [7].
• Concentrations of alpha- and beta-carotene, lycopene, beta-cryptoxanthin, zeaxanthin, lutein, alpha-, gamma-, and delta-tocopherol, retinol, and retinyl palmitate have been determined in over 1400 human sera from two epidemiological studies [8].

Biological context of C14151

• The prooxidant order of vitamin E analogues in catalyzing hepatocyte cytotoxicity, lipid peroxidation, and GSH oxidation was troglitazone > Trolox C > delta-tocopherol > gamma-tocopherol > alpha-tocopherol > PMC [9].
• The cytotoxicity observed with delta-tocopherol (delta-Toc) was associated with 2 markers of apoptosis [10].
• In acute studies, 24-h exposure to 0-250 microM alpha-, gamma-, and delta-tocopherol had no effect, whereas similar treatment with 100-250 microM TRF, 140-250 microM alpha-, 25-100 microM gamma- or delta-tocotrienol significantly reduced cell viability [11].
• Growth-inhibitory doses of TRF, delta-tocopherol, and alpha-, gamma-, and delta-tocotrienol were shown to induce apoptosis in these cells, as indicated by DNA fragmentation [11].
• 107 human milk samples (23 colostral, 22 transitional and 62 mature) obtained from six healthy mothers throughout the lactation were found to contain all the tocopherols, although delta-tocopherol occurred only in traces [12].

Anatomical context of C14151

• This study indicates that a mixture of tocopherols has a stronger inhibitory effect on lipid peroxidation induced in human erythrocytes than alpha-tocopherol alone, due to higher uptake of gamma- and delta-tocopherol in the cells [13].
• At higher total lipid contents, achieved by adding exogenous triacylglycerols, the delta-tocopherol concentration in the membranes increased relative to that in the triacylglycerols [14].
• Increasing levels of alpha-, gamma-, and delta-tocopherol were found in blood plasma with increasing dietary levels of these tocopherols [15].
• Normal mammary epithelial cells isolated from midpregnant BALB/c mice were grown in primary culture, and maintained on serum-free media containing 10 ng/mL EGF as a mitogen, and treated with various doses (0-250 microm) of alpha-, gamma-, or delta-tocopherol or alpha-, gamma-, or delta-tocotrienol [16].
• Infusion of Intralipid, a product derived from fractionated soybean oil, caused a significant increase of gamma- and delta-tocopherol in blood serum [17].

Associations of C14151 with other chemical compounds

• A liquid chromatographic (HPLC) method has been developed for the quantitative determination of different forms of vitamin E (alpha-, gamma-, and delta-tocopherol) in aquatic organisms [18].
• The aim of this study was to investigate the cutaneous penetration and metabolism of the new vitamin E prodrug delta-tocopherol glucoside (delta-TG), as compared to those of common vitamin E acetate, in vitro, both in reconstituted human epidermis and in viable human skin [19].
• Coenzyme Q, alpha-, gamma- and delta-tocopherol, fatty acids and the total antioxidant capacity of the milk were analyzed [20].
• We found that the plasma levels of lycopene, delta-tocopherol, gamma-tocopherol and retinol of hemodialysis patients were lower than those of controls [21].
• The partitioning of exogenous delta-tocopherol, added dissolved in ethanol, between the neutral triacylglycerols and membranes of chicken leg muscles was investigated [14].

Gene context of C14151

• Ketoconozole (1.0 microM), a potent and selective inhibitor of CYP3A, substantially inhibited metabolism of gamma- and alpha-tocopherol in rat primary hepatocytes, and metabolism of gamma- and delta-tocopherol in HepG2/C3A cells [22].
• Refeeding a diet containing either alpha- or delta-tocopherol, or both, caused a steady increase of the expression of alpha-TTP mRNA [7].
• (sect. Trionychon Wallr.). All the other accessions of this section presented high delta-tocopherol content [23].
• Since platelet aggregation is intimately involved in thrombogenesis, the relative effects of alpha-, gamma-, and delta-tocopherol and their combination were examined on human platelet aggregation, lipid peroxidation, and constitutive nitric oxide synthase (cNOS) activity [24].

Analytical, diagnostic and therapeutic context of C14151

• Prostate and liver were analyzed by HPLC for lycopene isomers and alpha- and gamma, delta-tocopherol concentrations [25].
• Lipophilic gel chromatography using Sephadex LH-20 helps in separating alpha-, beta- + -gamma, and delta-tocopherol and also in separation of their oxidation products e.g. the tocopherolquinones or other oxidation products [26].
• METHODS: Total, alpha-, beta-, gamma- and delta-tocopherol and alpha-tocopherolquinone concentrations were determined by high-performance liquid chromatography with a redox detection mode using a series of four coulometric working electrodes [27].
• To test this hypothesis and compare the various radioprotective and non-radioprotective analogs, we measured serum cytokines using a sandwich ELISA, Luminex, and cytokine array in mice treated with various tocols (alpha-tocopherol succinate, alpha-tocopherol, delta-tocopherol, gamma- tocopherol, gamma-tocotrienol, and tocopherol acetate) [28].

References