Disease relevance of alpha-Tocopherol

• Vitamin E repletion was achieved in all, either by large oral doses (up to 120 IU per kilogram of body weight per day) or by intramuscular administration of dl-alpha-tocopherol (0.8 to 2.0 IU per kilogram per day) [1].
• Intraluminal total bile acid concentrations were markedly depressed in group A compared with age-matched controls (0.50 vs. 7.00 mM, p less than 0.001), whereas concentrations were low normal in group B. Intramuscular dl-alpha-tocopherol was well absorbed in 4 group A subjects and corrected abnormal hydrogen peroxide hemolysis [2].
• In vitro enzyme assays confirmed that VTE3 is the plant functional equivalent of the previously characterized MPBQ/MSBQ MT (Sll0418) from Synechocystis sp PCC6803, although the two proteins are highly divergent in primary sequence [3].
• Arachidonic acid stimulated protein kinase C activity of erythroleukemia cells and promoted their adhesion, an effect that was also inhibited by dl-alpha-tocopherol [4].
• Effect of antioxidant therapy with dl-alpha-tocopherol on cardiovascular structure in experimental renal failure [5].

Psychiatry related information on alpha-Tocopherol

• In order to study effects of cigarette smoking and smoking cessation on plasma constituents and enzyme activities related to oxidative stress, 1255 smokers and 524 healthy non-smokers were investigated in terms of plasma levels of lipoperoxides (LPO), nitric oxide (NO), vitamin C (VC), vitamin E (VE) and beta-carotene (beta-CAR) [6].

High impact information on alpha-Tocopherol

• Intestinal absorption of dl-alpha-tocopherol (assessed by an oral tolerance test) was markedly impaired (p less than 0.001) in group A compared with groups B and C, which did not differ from each other [2].
• To test whether tocopherols (vitamin E) are essential in the protection against oxidative stress in plants, a series of Arabidopsis thaliana vitamin E (vte) biosynthetic mutants that accumulate different types and levels of tocopherols and pathway intermediates were analyzed under abiotic stress [7].
• Intriguingly, the only prokaryotic genomes that contain VTE3-like sequences are those of two species of archea, suggesting that, in contrast to all other enzymes of the plant tocopherol pathway, the evolutionary origin of VTE3 may have been archeal rather than cyanobacterial [3].
• VTE3 orthologs are present in all vascular and nonvascular plant databases and in C. reinhardtii but absent from cyanobacterial genomes [3].
• We therefore investigated the effect of 400 mg DL-alpha-tocopherol acetate daily for 4 wk on ADP- and collagen-induced platelet aggregation and platelet TXA2 production in 22 type I (insulin-dependent) diabetic patients without macroangiopathy and with no or only minimal microangiopathy by a double-blind placebo-controlled crossover study [8].

Chemical compound and disease context of alpha-Tocopherol

• Oxidation and toxicity were inhibited by DL-alpha-tocopherol (200 microM) and probucol (50 microM) [9].
• In further trials, daily im injections of sodium ascorbate with Dl-alpha tocopherol, desferrioxamine and oral butylated-hydroxyanisole prevented adrenal damage and induced adrenocortical hypertrophy of the zona fasciculata [10].
• Effect of dietary dl-alpha-tocopherol on tissue alpha- and gamma-tocopherol and pulmonary hypertension syndrome (ascites) in broilers [11].
• In contrast, none of the controls (vinpocetine and DL-alpha-tocopherol nicotinate) exerted effects on chorioretinal blood flow in the hypertension group [12].

Biological context of alpha-Tocopherol

• The results of this study indicate that plasma kinetics of alpha-tocopherol are similar when supplements of 440, 880, or 1320 mg dl-alpha-tocopherol are given to normal, healthy individuals [13].
• DL-alpha-Tocopherol completely inhibited lipid peroxidation induced by the ferriprotoporphyrin IX-chloroquine complex [14].
• The LD50/30 of CD-1 female mice increased from 6.6 Gy to 7.0 Gy when 2.5 mg of dl-alpha-tocopherol was injected immediately post irradiation [15].
• dl-alpha-tocopherol induces apoptosis in erythroleukemia, prostate, and breast cancer cells [16].
• Fanconi anemia lymphocytes: effect of DL-alpha-tocopherol (Vitamin E) on chromatid breaks and on G2 repair efficiency [17].

Anatomical context of alpha-Tocopherol

• In testis, the lipid peroxide levels were not as high as expected from the peroxidizability index, even in rats fed a high DHA diet containing the normal level of VE [18].
• Cholesteryl oleate/bovine serum albumin, which is taken up by macrophages but is not oxidized, was not toxic. dl-Alpha tocopherol was itself toxic in higher concentrations [19].
• We have studied the effect of dl-alpha-tocopherol (vitamin E) on a series of well-established cancer cell lines that included two erythroleukemia cell lines and a hormone-responsive breast and prostate cancer cell line [16].
• Similar results have been obtained with CHO cells treated with nonactivated BP and DL-alpha-tocopherol [20].
• In infested sheep, intramuscular (im) injections of Dl-Alpha tocopherol induced wool shedding and Desferrioxamine im prevented declines in white blood cells (WBC) [10].

Associations of alpha-Tocopherol with other chemical compounds

• In addition, in testis, VE and ascorbic acid, which act as antioxidants, were retained at higher levels in rats with particularly poor and normal VE nutriture than those of liver and kidney [18].
• The effects of the vitamins dl-alpha-tocopherol, ascorbic acid and beta-carotene, free radical scavengers and lipid peroxidation inhibitors, were analyzed in male Wistar rats made goitrous by feeding a low iodine diet (< 20 micrograms iodine/kg) and perchlorate (1% in drinking water) for 4, 8, 16, and 32 days [21].
• The effects of DL-alpha-tocopherol and DL-alpha-tocopherol succinate on neuroblastoma N1E 115 cells were studied [22].
• Dietary supplementation of VE and CLA increased their concentrations in turkey breast [23].
• Irradiation off-aroma of raw meat was not pleasant for most consumers, and dietary supplementation of VE and VE + Se improved consumer acceptance of irradiated raw meat [24].

Gene context of alpha-Tocopherol

• The administration of HYA and C4S starting at the onset of arthritis (day 11) for 20 days, limited inflammation and the clinical signs in the knee and paw, reduced OH* production, decreased CD levels, partially restored the endogenous antioxidants VE and CA, reduced MIP-2 serum levels and limited PMNs infiltration [25].
• The value of VC, VE and beta-CAR in plasma and that of SOD, CAT and GSH-Px in erythrocytes of PCg gradually decreased (P < 0.0001), representing a significant linear negative correlation [26].
• RESULTS: Baseline GSH and VE levels were significantly lower in the COPD group when compared with the control subjects [27].
• To determine if cancer can originate in utero, a high dietary dose of the antioxidant vitamin E (VE) (10% dl-alpha-tocopherol-acetate) was given to cancer-prone p53 knockout mice throughout pregnancy [28].
• Synthetic vitamin E, dl-alpha-tocopherol, added to a human erythroleukemia HEL and a megakaryoblastic leukemia, Meg-01, cell culture produced potent dose-dependent inhibition of phorbol ester-induced adhesion and of the morphologic changes accompanying it [4].

Analytical, diagnostic and therapeutic context of alpha-Tocopherol

• The treatment group received intramuscular injections of vitamin E (dl-alpha-tocopherol) on days 1, 2, 4, and 6 of life [29].
• The capacity of topical vitamin E (dl-alpha-tocopherol) to prevent photocarcinogenesis or the immunosuppression induced by UV irradiation were assessed [30].
• Thirty-five diabetics(D) were supplemented with DL-alpha-tocopherol (E) capsule (orally, 100 IU/d) or placebo (P) for three months in double-blind clinical trials [31].
• Oral administration of a single pharmacologic dose of dl-alpha-tocopherol (5 g) to sheep caused a slow increase of this vitamin in the blood plasma [32].
• Follow-up cardiac catheterization was obtained in 83% of the patients receiving placebo and in 86% of the patients receiving dl-alpha-tocopherol [33].

References