[en] A new synthetic method was developed for the preparation of gram quantities of d,1-α-tocopheryl acetate labeled with deuterium to d₆ and d₁₁. Mannich reaction of phenol was followed by conversion to the corresponding acetate and bromide. Reduction with D₂ afforded deuterated 2,4,6-trimethylphenol which provided the key intermediate (trimethyl hydroquinone) on oxidation. Subsequent reactions to the desired product were carried out following literature procedures. A second procedure using the less expensive LiAlD₄ was also developed in which the ester was eventually converted to TMHQ-d₆. 4 refs

[en] Highlights: • DCVC induced apoptosis in a placental cell line in a concentration-dependent manner. • DCVC activated both intrinsic and extrinsic apoptotic pathways via tBID cross talk. • DCVC stimulated differential intrinsic and extrinsic pathway gene expression. • Cellular lipid peroxidation byproduct malondyaldehyde levels were increased by DCVC. • Antioxidant (±)-α-tocopherol attenuated DCVC-induced caspase activity. Trichloroethylene (TCE), a prevalent environmental contaminant, is a potent renal and hepatic toxicant through metabolites such as S-(1, 2-dichlorovinyl)-l-cysteine (DCVC). However, effects of TCE on other target organs such as the placenta have been minimally explored. Because elevated apoptosis and lipid peroxidation in placenta have been observed in pregnancy morbidities involving poor placentation, we evaluated the effects of DCVC exposure on apoptosis and lipid peroxidation in a human extravillous trophoblast cell line, HTR-8/SVneo. We exposed the cells in vitro to 10–100 μM DCVC for various time points up to 24 h. Following exposure, we measured apoptosis using flow cytometry, caspase activity using luminescence assays, gene expression using qRT-PCR, and lipid peroxidation using a malondialdehyde quantification assay. DCVC significantly increased apoptosis in time- and concentration-dependent manners (p < 0.05). DCVC also significantly stimulated caspase 3, 7, 8 and 9 activities after 12 h (p < 0.05), suggesting that DCVC stimulates the activation of both the intrinsic and extrinsic apoptotic signaling pathways simultaneously. Pre-treatment with the tBID inhibitor Bl-6C9 partially reduced DCVC-stimulated caspase 3 and 7 activity, signifying crosstalk between the two pathways. Additionally, DCVC treatment increased lipid peroxidation in a concentration-dependent manner. Co-treatment with the antioxidant peroxyl radical scavenger (±)-α-tocopherol attenuated caspase 3 and 7 activity, suggesting that lipid peroxidation mediates DCVC-induced apoptosis in extravillous trophoblasts. Our findings suggest that DCVC-induced apoptosis and lipid peroxidation in extravillous trophoblasts could contribute to poor placentation if similar effects occur in vivo in response to TCE exposure, indicating that further studies into this mechanism are warranted.

[en] Highlights: • PGC-1a and UCP1 gene expressions were significantly increased by d-tocopherol treatment in 3T3 L1 cells. • PGC-1a and UCP1 protein expressions were increased in d-tocopherol-treated cells. • Nuclear translocation of PGC-1a was enhanced in d-tocopherol-treated cells. • PGC-1a knockdown canceled the induction of UCP1 gene expression by d-tocopherol treatment. • Expression and activation of p38 MAPK was enhanced by d-tocopherol treatment. Activation of thermogenic adipocytes (brown and beige) has been considered an attractive target for weight loss and treatment of metabolic disease. Peroxisome proliferator-activated receptor γ co-activator-1 α (PGC1-α) is a master regulator of thermogenic gene expression in thermogenic adipocytes. We previously reported that α-tocopherol upregulated PGC-1α gene expression and promoted thermogenic adipocyte differentiation in mammalian adipocytes. In this study, we investigated the effects of the vitamin E analogs (α-, γ- and δ-tocopherol) on PGC-1α and uncoupling protein 1 (UCP1) gene expression in 3T3-L1 cells. The expression of PGC-1α and UCP1 increased significantly with the addition of δ-tocopherol. In δ-tocopherol-treated cells, nuclear translocation of PGC-1α increased, as did p38 mitogen-activated protein kinase (MAPK) expression and phosphorylation. Our results suggest that p38 MAPK activation by δ-tocopherol contributes to PGC-1α activation and UCP1 induction.

[en] Vitamin E with a ¹³C-labeled isoprenoid side chain, [4' a-¹³C]-all-rac-α-tocopherol, was synthesized by the coupling reaction of 6-4-methoxymethoxy-2-([methyl-¹³C]5-bromo-4-methyl-pent-1-yl)chroman (8) with 3,7-dimethyl-1-(thiazolin-2-yl)thio-2,6-octadiene. Compound 8 was prepared using 2-(4,4-di-ethoxycarbonylbut-1-yl)-6-methoxymethoxy-2,5,7,8-tetramethyl-chroman as a key intermediate and [¹³C]methyl iodide as a ¹³C source. The total yield of the labeled α-tocopherol based on [¹³C]methyl iodide was 58.7%. (author)

[en] The association of pentoxiphyllin and tocopherols allows to correct the failure of healing of radio necrosis, although the waiting period seems in proportion longer than the volume is more important. The results of this study encourage to realize a randomized test. (N.C.)

[en] Radiation-induced (RI) peripheral neuropathy is a rare and severe delayed complication of radiotherapy that is spontaneously irreversible, with no standard of treatment. We previously developed a successful antioxidant treatment in RI fibrosis and necrosis. Two patients with progressive worsening RI lumbosacral poly-radiculopathy experienced over several years a significant clinical improvement in their neurological sensori-motor symptoms with long-term pentoxifylline-tocopherol-clodronate treatment, and good safety. (authors)

[en] Ethenyl indoles exhibit antioxidant activity in a substituent dependent manner and through electron transfer mechanism. Ethenyls with strong electron withdrawing substituent show lower antioxidant properties, whereas ethenyls with electron donating substituent exhibit antioxidant properties comparable to vitamin E. (author)

No abstract available

[en] Selenium (Se) is an essential trace element in animal nutrition involved in the defense against the toxicity of reactive oxygen species and the oxidation state of cells, where its deprivation reduces activities of the Se-dependent enzymes. The signs in animals depend upon vitamin E status and appear only when both nutrients are limiting where they vary according to species. Estimating actual selenium intake is often difficult due to the specific housing and feeding conditions of sheep husbandry, which is mostly in extensive system in most part of the world and in Iran as well. Indirect indices such as Se concentration in blood, glutathione peroxidase activity and production are used to evaluate Se status. Correct levels of selenium supplementation at different growth stages of sheep are essential to maximize productivity, but few studies have been conducted to determine the composition of mineral supplements for sheep in Iran. This study was designed to monitor the health status of sheep grazing in a dry land zone and to test the response of ewes to selenium vitamin E injection. Three flocks each with 120 sheep, representative as sheep husbandry system of a district zone in Markazi province in central Iran, were considered. Sheep keeping in this area is mostly based on the extensive system depends on poor rangeland, crop residues and stubbles with supplement feeding of barley grain during cool winter when the ewes are at late stage of pregnancy. In each of the selected flock, 60 ewes were identified and divided in two groups including 1) control and 2) treatment, where the ewes in treatment group received selenium-vitamin E (each dose contained 0.5 mg sodium selenate and 50 mg vitamin E) supplement by subcutaneous injections. Each ewe injected by one dose of the supplement 2 weeks before mating and again 2 weeks before lambing. Blood samples were collected, one month post injection that was occurrence to autumn and spring seasons, and analysed for glutathione peroxidase activity (GSH-px). The reproductive parameters were recorded and lamb body weight measured at birth day and weaning time as well. Results of the enzyme activity showed that the treatment had significant effect on the GSH-px at different seasons for flock I and II where the injection of Se-vitamin E increased the enzyme activity comparing to the control but no significant differences were found between the control and treatment in flock II. There were also significant variations of GSH-px among the flocks where the highest amount was found in flock III and the lowest amount in flock I. It may be a realistic explanation that no response was found in flock III as a result of injection. This finding may be indicated the probability of selenium deficiency in the flock and correction of deficiencies by supplementation. These results support the finding of other workers where they reported an increase in erythrocyte glutathione peroxidase activity (139.5 vs. 86.3 U/ml) in dairy ewes by subcutaneous injection of vitamin E and Se. Furthermore supplementation had positive effects on the reproductive performance in all flocks where the lambing rate and final lambs obtained per 100 sheep significantly (P < 0.05) increased in the treatment ewes than the control (Table II). However no differences were found between the treatment and control for the live weight of lambs at birth or weaning times. There was a positive relation between glutathione peroxidase activity and reproductive performance in ewes. It is suggested that reduced fertility and increased mortality of lambs may be related to congenital muscular dystrophy, arising from Se deficiency. (author)

[en] The amount of selenium in onions and potatoes was measured by Pixe (particle Induced X-ray Emission) in the Nuclear Center at Bordeaux-Gradignan (CNBG). The goal of this work is to investigate the level of selenium concentration that may be consumed by different class of people