Binding and uptake of {sup 125}iodine-labelled, oxidized low density lipoprotein by macrophages: Comparison of the effects of {alpha}-tocopherol, probucol, pyridoxal-5`-phosphate and magnesium-pyridoxal-5`-phosphate-glutamate

Energy Technology Data Exchange (ETDEWEB)

Selmer, D. [Technische Univ. Muenchen, Freising-Weihenstephan (Germany). Lehrstuhl fuer Phytopathologie; Senekowitsch-Schmidtke, R. [Technische Univ. Muenchen (Germany). Nuklearmedizinische Klinik; Schneider, W. [Steigerwald Arzneimittel, Darmstadt (Germany); Elstner, E.F. [Technische Univ. Muenchen, Freising-Weihenstephan (Germany). Lehrstuhl fuer Phytopathologie

1997-01-01

Specific and unspecific binding and uptake (internalization) by macrophages of {sup 125}iodine-labelled, copper-oxidized human low density lipoprotein is differently influenced by the anti-oxidants {alpha}-tocopherol ({alpha}-Toc), probucol (Prob), pyridoxal-5`-phosphate (PP) and the magnesium-pyridoxal-5`-phosphate glutamate complex (MPPG). Binding as well as internalization, mediated by the so-called `scavenger receptor` is lower in the presence of MPPG whereas both specific binding and internalization are enhanced. The comparison of the effects in vitro allows a rating of the potentially anti-atherogenic and thus protective effects of the tested substances as follows: MPPG>PP>{alpha}-Toc>Prob. (orig.)

Supplemental and highly-elevated tocopherol doses differentially regulate allergic inflammation: reversibility of α-tocopherol and γ-tocopherol's effects

OpenAIRE

McCary, Christine A.; Abdala-Valencia, Hiam; Berdnikovs, Sergejs; Cook-Mills, Joan M.

2011-01-01

We have reported that supplemental doses of the α- and γ-tocopherol isoforms of vitamin E decrease and increase, respectively, allergic lung inflammation. We have now assessed whether these effects of tocopherols are reversible. For these studies, mice were treated with antigen and supplemental tocopherols in a first phase of treatment followed by a 4 week clearance phase and then the mice received a second phase of antigen and tocopherol treatments. The pro-inflammatory effects of supplement...

δ-Tocopherol Is More Active than α- or γ-Tocopherol in Inhibiting Lung Tumorigenesis In Vivo

Science.gov (United States)

Li, Guang Xun; Lee, Mao-Jung; Liu, Anna Ba; Yang, Zhihong; Lin, Yong; Shih, Weichung Joe; Yang, Chung S.

2011-01-01

In contrast to strong epidemiologic, preclinical, and secondary clinical evidence for vitamin E (tocopherols) in reducing cancer risk, large-scale clinical cancer-prevention trials of α-tocopherol have been negative. This vexing contrast helped spur substantial preclinical efforts to better understand and improve the antineoplastic activity of tocopherol through, for example, the study of different tocopherol forms. We previously showed that the γ-tocopherol–rich mixture (γ-TmT) effectively inhibited colon and lung carcinogenesis and the growth of transplanted lung-cancer cells in mice. We designed the present study to determine the relative activities of different forms of tocopherol in a xenograft model, comparing the anticancer activities of δ-tocopherol with those of α- and γ-tocopherols. We subcutaneously injected human lung cancer H1299 cells into NCr nu/nu mice, which then received α-, γ-, or δ-tocopherol or γ-TmT in the diet (each at 0.17% and 0.3%) for 49 days. δ-Tocopherol inhibited tumor growth most strongly. γ-Tocopherol and γ-TmT (at 0.3%) also inhibited growth significantly, but α-tocopherol did not. δ-Tocopherol also effectively decreased oxidative DNA damage and nitrotyrosine formation and enhanced apoptosis in tumor cells; again, γ-tocopherol also was active in these regards but less so, and α-tocopherol was not. Each supplemented diet increased serum levels of its tocopherol—up to 45 µM for α-tocopherol, 9.7 µM for γ-tocopherol, and 1.2 µM for δ-tocopherol; dietary γ- or δ-tocopherol, however, decreased serum α-tocopherol levels, and dietary α-tocopherol decreased serum levels of γ-tocopherol. Each dietary tocopherol also increased its corresponding side-chain–degradation metabolites, with concentrations of δ-tocopherol metabolites greater than γ-tocopherol and far greater than α-tocopherol metabolites in serum and tumors. The present study is the first in vivo assessment of δ-tocopherol in tumorigenesis and

Roselle (Hibiscus sabdariffa) seed oil is a rich source of gamma-tocopherol.

Science.gov (United States)

Mohamed, R; Fernández, J; Pineda, M; Aguilar, M

2007-04-01

The antioxidant potential of roselle (Hibiscus sabdariffa L.) extracts was studied. Different plant organs, including seeds, stems, leaves, and sepals, were analyzed with respect to their water-soluble antioxidant capacity, lipid-soluble antioxidant capacity, and tocopherol content, revealing that roselle seeds are a good source of lipid-soluble antioxidants, particularly gamma-tocopherol. Roselle seed oil was extracted and characterized, and its physicochemical parameters are summarized: acidity, 2.24%; peroxide index, 8.63 meq/kg; extinction coefficients at 232 (k(232)) and 270 nm (k(270)), 3.19 and 1.46, respectively; oxidative stability, 15.53 h; refractive index, 1.477; density, 0.92 kg/L; and viscosity, 15.9 cP. Roselle seed oil belongs to the linoleic/oleic category, its most abundant fatty acids being C18:2 (40.1%), C18:1 (28%), C16:0 (20%), C18:0 (5.3%), and C19:1 (1.7%). Sterols include beta-sitosterol (71.9%), campesterol (13.6%), Delta-5-avenasterol (5.9%), cholesterol (1.35%), and clerosterol (0.6%). Total tocopherols were detected at an average concentration of 2000 mg/kg, including alpha-tocopherol (25%), gamma-tocopherol (74.5%), and delta-tocopherol (0.5%). The global characteristics of roselle seed oil suggest that it could have important industrial applications, adding to the traditional use of roselle sepals in the elaboration of karkade tea.

A practical study on the feasibility of alpha and gamma-tocopherol quantification for distinguishing Iberian pig feeding systems

Directory of Open Access Journals (Sweden)

García-Casco, J.

2013-04-01

Full Text Available This study was undertaken to test the feasibility of using alpha and gamma-tocopherol quantification in fat and muscle to establish a correct classification of Iberian pigs according to their feeding background in practical situations. Samples were obtained over three different seasons from the four categories of pigs described in the Industry Quality Policy (FREE-OUT “bellota”; FREE-OUT-FEED “recebo”; FEEDOUT “campo”; and FEED-IN “cebo”. Linear discriminant functions were calculated with data obtained from seasons 1 and 2 and validated. The classification of fat and muscle samples from season 3 in the four feeding categories according to the calculated discriminant functions achieved an average of 76% success rate in distinguishing the true origin of pig samples. Quantification in muscle seemed to have higher prediction ability. Regression equations to quantify weight gained depending on the gamma-tocopherol concentration had higher R2 values for muscle than for fat (R2= 0.81 vs. 0.62. Merging of the feeding categories established by the Quality Policy could raise the accuracy of the alpha and gamma-tocopherol quantification method to up to between 89% and 98%.Este estudio se llevó a cabo para comprobar la fiabilidad del uso de la cuantificación de alfa y gamma-tocoferol en grasa y músculo para establecer una clasificación correcta de los cerdos ibéricos de acuerdo a su alimentación. Las muestras se obtuvieron durante tres campañas diferentes procedentes de cuatro categorías de cerdos según se describe en la norma de calidad (FREE-OUT: «bellota», FREEOUT- FEED: «recebo», FEED-OUT: «campo» y FEED-IN: «cebo». Se calcularon funciones discriminantes con los datos obtenidos de las campañas 1 y 2 y se validaron. La clasificación de las muestras de grasa y músculo obtenidas de la tercera campaña en las cuatro categorías de acuerdo a las funciones discriminantes calculadas alcanzó un rango medio de éxito del 76

Distribution of vitamins A (retinol) and E (alpha-tocopherol) in polar bear kidney: Implications for biomarker studies

DEFF Research Database (Denmark)

Bechshøft, T.Ø.; Jakobsen, Jette; Sonne, C.

2011-01-01

of the organ to sample in order to get a representative value for this important biomarker. The aim here was to assess the distribution of vitamins A (retinol) and E (α-tocopherol) within the polar bear multireniculate kidney (i.e. polar vs. medial position) and also within the cortex vs. medulla of each...... separate renculi. The results showed no significant difference between the medial and polar renculi with regards to either retinol (p=0.44) or α-tocopherol (p=0.75). There were, however, significant differences between cortex and medulla for both vitamins (retinol, p=0.0003; α-tocopherol, p...

Evaluation of a-tocopherol in virgin olive oil by a luminescent method

Energy Technology Data Exchange (ETDEWEB)

Escuderos, M. E.; Sayago, A.; Morales, M. T.; Aparicio, R.

2009-07-01

Natural fluorophores such as tocopherols are of great importance for the characterization and authentication of virgin olive oil. The band of the luminescent spectrum which is most accurately associated with the presence of a- tocopherol (380-420 nm) at {lambda}{sub e}xc = 350 nm was detected and its precision was evaluated once the analytical process was optimized. A virgin olive oil, cv. Cornicabra, was spiked with several quantities of a-tocopherol, from 25 mg/Kg to 1200mg/Kg, to build a ridge regression model (adjusted-R{sup 2} = 0.99) based on five wavelengths (370, 371, 378, 414 and 417 nm) which are attributed to the fluorescence of this compound. The tentative model was validated (adjusted-R2 = 0.87) with 8 samples of a virgin olive oil, cv. Picual, spiked with amounts of {alpha}-tocopherols ranging from 25 mg/kg to 250mg/kg. Finally, the model was successfully validated with 7 mono varietal virgin olive oils from various olive producing countries (adjusted - R{sup 2} = 0.92). (Author) 23 refs.

The monoterpene terpinolene from the oil of Pinus mugo L. in concert with alpha-tocopherol and beta-carotene effectively prevents oxidation of LDL.

Science.gov (United States)

Grassmann, J; Hippeli, S; Spitzenberger, R; Elstner, E F

2005-06-01

Antioxidants from several nutrients, e.g. vitamin E, beta-carotene, or flavonoids, inhibit the oxidative modification of low-density lipoproteins. This protective effect could possibly retard atherogenesis and in consequence avoid coronary heart diseases. Some studies have shown a positive effect of those antioxidants on cardiovascular disease. Another class of naturally occurring antioxidants are terpenoids, which are found in essential oils. The essential oil of Pinus mugo and the contained monoterpene terpinolene effectively prevent low-density lipoprotein (LDL)-oxidation. In order to test the mechanism by which terpinolene protects LDL from oxidation, LDL from human blood plasma enriched in terpinolene was isolated. In this preparation not only the lipid part of LDL is protected against copper-induced oxidation--as proven by following the formation of conjugated dienes, but also the oxidation of the protein part is inhibited, since loss of tryptophan fluorescence is strongly delayed. This inhibition is due to a retarded oxidation of intrinsic carotenoids of LDL, and not, as in the case of some flavonoids, attributable to a protection of intrinsic alpha-tocopherol. These results are in agreement with our previous results, which showed the same effects for a monoterpene from lemon oil, i.e. gamma-terpinene.

Transformation of alpha-tocopherol (vitamin E) and related chromanol model compounds into their phenoxonium ions by chemical oxidation with the nitrosonium cation.

Science.gov (United States)

Lee, Stephen B; Lin, Ching Yeh; Gill, Peter M W; Webster, Richard D

2005-12-09

[reaction: see text] Alpha-tocopherol (alpha-TOH), the main oil component making up vitamin E, and its nonnatural solid 6-hydroxy-2,2,5,7,8-pentamethylchroman and 6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid structurally related analogues were oxidized quantitatively with 2 mol equiv of NO+ SbF6(-) in CH3CN at 233 K to form phenoxonium cations (alpha-TO+ SbF6(-)) in a chemically reversible two-electron/one-proton process. Solution-phase infrared spectroscopy, 1H and 13C NMR spectroscopy, and corresponding theoretical calculations of the spectroscopic data using density-based and wave-function-based models support the identity of the remarkably stable phenoxonium cations. The presence of an oxygen atom in the para position to the hydroxyl group and the chromanol ring structure appear to be important factors in stabilization of the phenoxonium ions, which raises the interesting possibility that the cations play a crucial role in the mode of action of vitamin E in biological systems. Although the phenoxonium cations are reactive toward nucleophiles such as water, they may be moderately stable in the hydrophobic (lipophilic) environment where vitamin E is known to occur naturally.

Tocopherol and tocotrienol levels of foods consumed in Hawaii.

Science.gov (United States)

Franke, Adrian A; Murphy, Suzanne P; Lacey, Rochelle; Custer, Laurie J

2007-02-07

Because of the individual biological effects and the uncertain or missing information on levels of tocopherols (T) and tocotrienols (T3) in foods frequently consumed in Hawaii, 79 food items (50 in duplicate) were analyzed for alpha-, beta-, gamma-, and delta-tocopherol (alphaT, betaT, gammaT, and deltaT) and alpha-, beta-, gamma-, and delta-tocotrienol (alphaT3, betaT3, gammaT3, and deltaT3) in addition to alpha-tocopheryl acetate (alphaTac). Foods from local markets were stored according to usual household habits, freeze-dried, homogenized, and extracted three times with hexane containing butylated hydroxytoluene as a preservative and tocol as an internal standard. A normal-phase high-pressure liquid chromatography system was applied with fluorescence and photodiode array detection that resulted in baseline separation of all eight analytes and the internal standard tocol (To). The sum of all E vitamer concentrations, or total E vitamers (TEV), in all foods analyzed ranged an average from 0.6 to 828 mg/kg (T oils, 497-828 mg/kg (mainly alphaT and gammaT); margarines, 359-457 mg/kg (mainly gammaT); salad dressings, 20-291 mg/kg (mainly gammaT, except alphaT when soy oil was the main ingredient); cookies, 54-138 mg/kg (mainly gammaT); snacks, 101-220 mg/kg (mainly gammaT); nuts, 22-201 mg/kg (mainly alphaT); vegetables, 2-152 mg/kg (mainly alphaT); pasta, 24-90 mg/kg; cereals, 4-56 mg/kg (mainly betaT3 followed by alphaT); fish, 2-39 mg/kg (mainly alphaT); fried tofu, 64 mg/kg (mainly gammaT); breads, 20-22 mg/kg (mainly betaT3); fat-free mayonnaise, 5 mg/kg (mainly alphaT); poi (fermented taro root), 2 mg/kg (mostly alphaT); and fruits, 2 (papaya) to 13 mg/kg (canned pumpkin) with alphaT predominating. Cereals fortified with alphaTac ranked third and eighth among all foods assayed regarding alphaT and TEV levels, respectively. As compared to the few data available in the literature, our values agreed with some (corn flakes, mango fruit, fat-free mayonnaise, dry

Sensitive electrochemical detection of native and aggregated alpha-synuclein protein involved in Parkinson's disease

Czech Academy of Sciences Publication Activity Database

Masařík, Michal; Stobiecka, A.; Kizek, René; Jelen, František; Pechan, Zdeněk; Hoyer, W.; Jovin, T.; Subramaniam, V.; Paleček, Emil

2004-01-01

Roč. 16, 13-14 (2004), s. 1172-1181 ISSN 1040-0397 R&D Projects: GA ČR GA204/03/0566 Institutional research plan: CEZ:AV0Z5004920 Keywords : electrochemistry of proteins * alpha-synuclein aggregation * adsorptive transfer stripping Subject RIV: BO - Biophysics Impact factor: 2.038, year: 2004

Humoral immune response of mice injected with tocopherol after exposure to X-radiation

International Nuclear Information System (INIS)

Roy, R.M.; Petrella, M.

1987-01-01

Serum haemagglutination (HA) titers have been determined for irradiated and non-irradiated mice responding to injection of two different concentrations of sheep red blood cells (SRBC) 24 to 48 hours after irradiation and immediate intraperitoneal injection of 2.5 mg DL alpha-tocopherol, the emulsifying vehicle, or saline. Mice maintained on tocopherol-deficient diets for 8 weeks post-weaning and those on regular diets exhibited increased IgG titers during peak response when injected with vitamin E. This partially alleviated the radiation-depression of the primary immune response induced by the smaller SRBC injection. This stimulatory effect was most significant in mice maintained on vitamin E-deficient diets. The HA titers of irradiated and non-irradiated mice maintained on normal rations were determined following a 10-fold increase in the SRBC inoculation. Antibody titer was greater following injection of the higher concentration of SRBC but post-irradiation injection of tocopherol immediately or 24 hours after irradiation did not enhance immune response. At the higher SRBC concentration maximum observed HA titers decreased with increasing dose of radiation; however, tocopherol had no significant dose-reducing effect. Tocopherol toxicity as manifested by depressed HA titers was observed occasionally in non-irradiated mice challenged with the higher concentration of SRBC

Low Plasma alpha-Tocopherol Concentrations and Adverse Clinical Outcomes in Diabetic Hemodialysis Patients

NARCIS (Netherlands)

Espe, K.M.; Raila, J.; Henze, A.; Blouin, K.; Schneider, A.; Schmiedeke, D.; Krane, V.; Pilz, S.; Schweigert, F.J.; Hocher, B.; Wanner, C.; Drechsler, C.

2013-01-01

Background and objectives Trials with the antioxidant vitamin E have failed to show benefit in the general population. Considering the different causes of death in ESRD, this study investigated the association between plasma concentrations of α-tocopherol and specific clinical outcomes in diabetic

Tocopherol isomer pattern in serum and stool of human following consumption of black currant seed press residue administered in whole grain bread.

Science.gov (United States)

Helbig, Dorit; Wagner, Andreas; Schubert, Rainer; Jahreis, Gerhard

2009-12-01

Serum gamma-tocopherol is thought to be associated with human health. The dietary influence of tocopherol and fibre-rich black currant seed press residue on serum and stool tocopherol concentration was investigated in a controlled human intervention study. Thirty-six women consumed bread enriched with black currant press residue (4 weeks). The resultant faecal and serum tocopherol concentrations were compared with those after a period consuming control bread without press residue and a normal baseline diet. Fibre intake and excretion, antioxidant capacity (TEAC), and vitamin C concentrations in serum and urine were also determined. Samples were obtained with a 5-day standardised diet at the end of each period. The press residue bread lead to significantly increased beta-, gamma-, delta- and total tocopherol intake, serum alpha-, beta-, gamma- and total tocopherol concentration (with and without lipid adjustment), fibre intake and urinary vitamin C concentration compared to control bread (Pconsumption could be due to a presumed interruption of the enzymatic tocopherol degradation mechanism by bread constituents.

The alpha-tocopherol content of leaves of pedunculate oak (Quercus robur L.)--variation over the growing season and along the vertical light gradient in the canopy.

Science.gov (United States)

Hansen, Ute; Schneiderheinze, Jenny; Stadelmann, Simone; Rank, Barbara

2003-01-01

This study was performed in order to investigate whether the actual requirement for defence against photo-oxidative stress is reflected by the alpha-tocopherol (alpha-Toco) content in leaves of pedunculate oak (Quercus robur L.). Antioxidants and pigments were quantified in leaves that were collected on six days between May and September 2000 in a mixed pine/oak forest at canopy positions differing in light environment. Pools of hydrophilic antioxidants and photo-protective xanthophyll cycle pigments (V + A + Z) reflected the anti-oxidative demand, as these pools increased with the average light intensity to which the leaves were acclimated. The photo-protective demand was not the determinant of the alpha-Toco content of oak leaves, as (1) foliage of a young oak, exposed to low light levels in the understorey, contained higher amounts of this lipophilic antioxidant than leaves sampled from semimature oaks at canopy positions with a similar light environment, and (2) a strong increase in the alpha-Toco content over the growing season was detected at each investigated crown position, whereas the V + A + Z pool did not show a concomitant accumulation during leaf ageing. The rate of alpha-Toco accumulation differed distinctly between samples taken at different canopy positions.

Alpha-Tocopherol alters transcription activities that modulate tumor necrosis factor alpha (TNF-¿)-induced inflammatory response in bovine cells

Science.gov (United States)

To further investigate the potential role of '-tocopherol in maintaining immuno-homeostasis in bovine cells (Madin-Darby bovine kidney epithelial cell line), we undertook in vitro experiments using recombinant TNF-a as an immuno-stimulant to simulate inflammation response in cells with and without '...

Prevention and Treatment of Functional and Structural Radiation Injury in the Rat Heart by Pentoxifylline and Alpha-Tocopherol

International Nuclear Information System (INIS)

Boerma, Marjan; Roberto, Kerrey A.; Hauer-Jensen, Martin

2008-01-01

Purpose: Radiation-induced heart disease (RIHD) is a severe side effect of thoracic radiotherapy. This study examined the effects of pentoxifylline (PTX) and α-tocopherol on cardiac injury in a rat model of RIHD. Methods and Materials: Male Sprague-Dawley rats received fractionated local heart irradiation with a daily dose of 9 Gy for 5 days and were observed for 6 months after irradiation. Rats were treated with a combination of PTX, 100 mg/kg/day, and α-tocopherol (20 IU/kg/day) and received these compounds either from 1 week before until 6 months after irradiation or starting 3 months after irradiation, a time point at which histopathologic changes become apparent in our model of RIHD. Results: Radiation-induced increases in left ventricular diastolic pressure (in mm Hg: 35 ± 6 after sham-irradiation, 82 ± 11 after irradiation) were significantly reduced by PTX and α-tocopherol (early treatment: 48 ± 7; late treatment: 53 ± 6). PTX and α-tocopherol significantly reduced deposition of collagen types I (radiation only: 3.5 ± 0.2 μm 2 per 100 μm 2 ; early treatment: 2.7 ± 0.8; late treatment: 2.2 ± 0.2) and III (radiation only: 13.9 ± 0.8; early treatment: 11.0 ± 1.2; late treatment: 10.6 ± 0.8). On the other hand, radiation-induced alterations in heart/body weight ratios, myocardial degeneration, left ventricular mast cell densities, and most echocardiographic parameters were not significantly altered by PTX and α-tocopherol. Conclusions: Treatment with PTX and α-tocopherol may have beneficial effects on radiation-induced myocardial fibrosis and left ventricular function, both when started before irradiation and when started later during the process of RIHD

Influences of a-tocopherol on cholesterol metabolism and fatty streak development in apolipoprotein E-deficient mice fed an atherogenic diet

Directory of Open Access Journals (Sweden)

Peluzio M.C.G.

2001-01-01

Full Text Available Although the role of oxidized lipoproteins is well known in atherogenesis, the role of vitamin E supplementation is still controversial. There is also little information about cholesterol metabolism (hepatic concentration and fecal excretion in the new models of atherosclerosis. In the present study, we evaluated the effect of moderate vitamin E supplementation on cholesterol metabolism and atherogenesis in apolipoprotein E (apo E-deficient mice. Apo E-deficient mice were fed an atherogenic diet containing 40 or 400 mg/kg of alpha-tocopherol acetate for 6 weeks. Total cholesterol in serum and liver and 3-OH-alpha-sterols in feces, and fecal excretion of bile acids were determined and histological analyses of aortic lesion were performed. A vitamin E-rich diet did not affect body weight, food intake or serum cholesterol. Serum and hepatic concentrations of cholesterol as well as sterol concentration in feces were similar in both groups. However, when compared to controls, the alpha-tocopherol-treated mice showed a reduction of about 60% in the atherosclerotic lesions when both the sum of lesion areas and the average of the largest lesion area were considered. These results demonstrate that supplementation of moderate doses of alpha-tocopherol was able to slow atherogenesis in apo E-deficient mice and to reduce atherogenic lipoproteins without modifying the hepatic pool or fecal excretion of cholesterol and bile acids.

The naturally occurring α-tocopherol stereoisomer RRR-α-tocopherol is predominant in the human infant brain

DEFF Research Database (Denmark)

Kuchan, J M; Jensen, Søren Krogh; Johnson, E J

2016-01-01

α-Tocopherol is the principal source of vitamin E, an essential nutrient that plays a crucial role in maintaining healthy brain function. Infant formula is routinely supplemented with synthetic α-tocopherol, a racaemic mixture of eight stereoisomers with less bioactivity than the natural...... stereoisomer RRR-α-tocopherol. α-Tocopherol stereoisomer profiles have not been previously reported in the human brain. In the present study, we analysed total α-tocopherol and α-tocopherol stereoisomers in the frontal cortex (FC), hippocampus (HPC) and visual cortex (VC) of infants (n 36) who died of sudden...... infant death syndrome or other conditions. RRR-α-tocopherol was the predominant stereoisomer in all brain regions (Ptocopherol (5–17 μg/g). Mean RRR-α-tocopherol concentrations in FC, HPC and VC were 10·5, 6·8 and 5·5 μg...

A comparison of carotenoids, retinoids, and tocopherols in the serum and buccal mucosa of chronic cigarette smokers versus nonsmokers.

Science.gov (United States)

Gabriel, Helen E; Liu, Zhenhua; Crott, Jimmy W; Choi, Sang-Woon; Song, Byeng Chun; Mason, Joel B; Johnson, Elizabeth J

2006-05-01

Cigarette smoking, a major risk factor for oropharyngeal cancer, is reported to alter oral levels of carotenoids and tocopherols. Such effects may be important because these nutrients, as well as retinoids, are putative chemoprotective agents. To determine whether chronic smoking is associated with altered concentrations of these nutrients in serum and buccal mucosa; to distinguish whether such effects are ascribable to diet; and to determine whether oral concentrations of these nutrients correlate with a putative biomarker of oral cancer risk. Serum and buccal mucosal cells (BMC) were analyzed for these nutrients and for BMC micronuclei in smokers (n = 35) and nonsmokers (n = 21). General linear regression with adjustments for dietary intake showed that smokers possess lower serum concentrations of beta- and alpha-carotene, cryptoxanthin, lutein, and zeaxanthin (P tocopherol (P = 0.03). In BMCs, smokers had significantly lower concentrations of beta- and alpha-carotene, lycopene, and alpha-tocopherol (P < 0.05) but significantly higher gamma-tocopherol (P < 0.01). Among nonsmokers, many serum carotenoid concentrations correlated with concentrations of the corresponding nutrient in BMCs whereas no such correlations existed among smokers. BMC micronuclei did not correlate with the oral concentration of any micronutrient. Chronic cigarette smokers have lower concentrations of many dietary antioxidants in serum and BMCs compared with nonsmokers, an effect which is not entirely ascribable to diet. Nevertheless, the lack of concordance between oral concentrations of these nutrients and genetic damage in the BMCs of smokers does not support a protective role for these nutrients in oral carcinogenesis.

Molecular cloning, heterologous expression and functional characterization of gamma tocopherol methyl transferase (γ-TMT) from Glycine max.

Science.gov (United States)

Tewari, Kalpana; Dahuja, Anil; Sachdev, Archana; Kumar, Vaibhav; Ali, Kishwar; Kumar, Amresh; Kumari, Sweta

2017-12-01

γ-Tocopherol methyltransferase (γ-TMT) (EC 2.1.1.95) is the last enzyme in the tocopherol biosynthetic pathway and it catalyzes the conversion of γ-tocopherol into α-tocopherol, the nutritionally significant and most bioactive form of vitamin E. Although the γ-TMT gene has been successfully overexpressed in many crops to enhance their α-tocopherol content but still only few attempts have been made to uncover its structural, functional and regulation aspects at protein level. In this study, we have cloned the complete 909bp coding sequence of Glycine max γ-TMT (Gm γ-TMT) gene that encodes the corresponding protein comprising of 302 amino acid residues. The deduced Gm γ-TMT protein showed 74-87% sequence identity with other characterized plant γ-TMTs. Gm γ-TMT belongs to Class I Methyl Transferases that have a Rossmann-like fold which consists of a seven-stranded β sheet joined by α helices. Heterologous expression of Gm γ-TMT in pET29a expression vector under the control of bacteriophage T7 promoter produced a 37.9 kDa recombinant Gm γ-TMT protein with histidine hexamer tag at its C-terminus. The expression of recombinant Gm γ-TMT protein was confirmed by western blotting using anti-His antibody. The recombinant protein was purified by Ni 2+ -NTA column chromatography. The purified protein showed SAM dependent methyltransferase activity. The α-tocopherol produced in the in-vitro reaction catalyzed by the purified enzyme was detected using reverse phase HPLC. This study has laid the foundation to unveil the biochemical understanding of Gm γ-TMT enzyme which can be further explored by studying its kinetic behaviour, substrate specificity and its interaction with other biomolecules. Copyright © 2017 Elsevier Inc. All rights reserved.

Tocopherols in the Prevention and Treatment of Atherosclerosis and Related Cardiovascular Disease.

Science.gov (United States)

Mathur, Pankaj; Ding, Zufeng; Saldeen, Tom; Mehta, Jawahar L

2015-09-01

Oxidants/antioxidants play an important role in cellular homeostasis. The human body has endogenous molecules that work as antioxidants, such as glutathione, superoxide dismutase, peroxidases, and catalase. Exogenous substances in the diet, such as β-carotene, ascorbate, and vitamin E, are vital antioxidants. Of these, vitamin E is likely the most important antioxidant in the human diet, and many studies have been performed to elucidate its role in health and disease. Vitamin E is a family of several compounds, of which α-tocopherol is the most widely known analog. α-Tocopherol exhibits antioxidative property in vitro and inhibits oxidation of low-density lipoprotein cholesterol. In addition, α-tocopherol shows anti-inflammatory activity and modulates expression of proteins involved in the uptake, transport, and degradation of atherogenic lipids. Though α-tocopherol exhibits important antioxidant, anti-inflammatory, and antiatherogenic features in vitro, α-tocopherol supplements have failed to consistently reduce atherosclerosis-related events in human trials. The conflicting results have led to reconsideration of the importance previously given to α-tocopherol and led to interest in other members of vitamin E family, especially γ-tocopherol, which exerts a much more potent antioxidant, anti-inflammatory, and cardioprotective effect than α-tocopherol. This reconsideration has been backed by solid laboratory and clinical research. We suggest that the absence of γ-tocopherol in traditional preparations may be one reason for the lack of consistent salutary effects of vitamin E preparations in clinical trials. This review summarizes our current understanding of tocopherols as antioxidant molecules and emerging evidence of an important role of γ-tocopherol in the pathophysiology of atherosclerosis-related cardiovascular disease. © 2015 Wiley Periodicals, Inc.

Maternal dietary loads of alpha-tocopherol increase synapse density and glial synaptic coverage in the hippocampus of adult offspring

Directory of Open Access Journals (Sweden)

S. Salucci

2014-05-01

Full Text Available An increased intake of the antioxidant α-Tocopherol (vitamin E is recommended in complicated pregnancies, to prevent free radical damage to mother and fetus. However, the anti-PKC and antimitotic activity of α-Tocopherol raises concerns about its potential effects on brain development. Recently, we found that maternal dietary loads of α-Tocopherol through pregnancy and lactation cause developmental deficit in hippocampal synaptic plasticity in rat offspring. The defect persisted into adulthood, with behavioral alterations in hippocampus-dependent learning. Here, using the same rat model of maternal supplementation, ultrastructural morphometric studies were carried out to provide mechanistic interpretation to such a functional impairment in adult offspring by the occurrence of long-term changes in density and morphological features of hippocampal synapses. Higher density of axo-spinous synapses was found in CA1 stratum radiatum of α-Tocopherol-exposed rats compared to controls, pointing to a reduced synapse pruning. No morphometric changes were found in synaptic ultrastructural features, i.e., perimeter of axon terminals, length of synaptic specializations, extension of bouton-spine contact. Glia-synapse anatomical relationship was also affected. Heavier astrocytic coverage of synapses was observed in Tocopherol-treated offspring, notably surrounding axon terminals; moreover, the percentage of synapses contacted by astrocytic endfeet at bouton-spine interface (tripartite synapses was increased. These findings indicate that gestational and neonatal exposure to supranutritional tocopherol intake can result in anatomical changes of offspring hippocampus that last through adulthood. These include a surplus of axo-spinous synapses and an aberrant glia-synapse relationship, which may represent the morphological signature of previously described alterations in synaptic plasticity and hippocampus-dependent learning.

Effects of brown seaweed polyphenols, α-tocopherol, and ascorbic acid on protein oxidation and textural properties of fish mince (Pagrosomus major) during frozen storage.

Science.gov (United States)

Wang, Tiantian; Li, Zhenxing; Yuan, Fangzhou; Lin, Hong; Pavase, Tushar Ramesh

2017-03-01

Frozen storage of minced fish is currently one of the most important techniques to maintain its functional properties. However, some deterioration does occur during frozen storage and cause quality loss. The effects of brown seaweed polyphenols, α-tocopherol, and ascorbic acid on lipid and protein oxidation and textural properties of red sea bream (Pagrosomus major) during 90 days of frozen storage at -18 °C were investigated. All added antioxidants at 1 g kg -1 resulted in significantly lower thiobarbituric acid-reactive substances (TBARS) compared to the control during the 45 days of frozen storage. The antioxidants were also effective in retarding protein oxidation concerning to total sulfhydryl content and protein carbonyl content. Brown seaweed polyphenols and α-tocopherol significantly retarded the inactivation of Ca 2+ -ATPase activity during the first 45 days, whereas ascorbic acid had no such effect. The antioxidant activity showed either an invariable or decrease trend after 45 days storage. Adding antioxidants had a significant effect on the breaking force of the gels during the frozen storage period. These results indicate that brown seaweed polyphenols and α-tocopherol can be used to prevent oxidative reactions and thus maintain the structure of the gel formed by fish mince during frozen storage. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Genetic variation of γ-tocopherol methyltransferase gene contributes to elevated α-tocopherol content in soybean seeds.

Science.gov (United States)

Dwiyanti, Maria S; Yamada, Tetsuya; Sato, Masako; Abe, Jun; Kitamura, Keisuke

2011-11-07

Improvement of α-tocopherol content is an important breeding aim to increase the nutritional value of crops. Several efforts have been conducted to improve the α-tocopherol content in soybean [Glycine max (L.) Merr.] through transgenic technology by overexpressing genes related to α-tocopherol biosynthesis or through changes to crop management practices. Varieties with high α-tocopherol content have been identified in soybean germplasms. The heritability of this trait has been characterized in a cross between high α-tocopherol variety Keszthelyi Aproszemu Sarga (KAS) and low α-tocopherol variety Ichihime. In this study, the genetic mechanism of the high α-tocopherol content trait of KAS was elucidated. Through QTL analysis and fine mapping in populations from a cross between KAS and a Japanese variety Ichihime, we identified γ-TMT3, which encodes γ-tocopherol methyltransferase, as a candidate gene responsible for high α-tocopherol concentration in KAS. Several nucleotide polymorphisms including two nonsynonymous mutations were found in the coding region of γ-TMT3 between Ichihime and KAS, but none of which was responsible for the difference in α-tocopherol concentration. Therefore, we focused on transcriptional regulation of γ-TMT3 in developing seeds and leaves. An F5 line that was heterozygous for the region containing γ-TMT3 was self-pollinated. From among the progeny, plants that were homozygous at the γ-TMT3 locus were chosen for further evaluation. The expression level of γ-TMT3 was higher both in developing seeds and leaves of plants homozygous for the γ-TMT3 allele from KAS. The higher expression level was closely correlated with high α-tocopherol content in developing seeds. We generated transgenic Arabidopsis plants harboring GUS gene under the control of γ-TMT3 promoter from KAS or Ichihime. The GUS activity assay showed that the activity of γ-TMT3 promoter from KAS was higher than that of Ichihime. The genetic variation in γ-TMT3

Genetic variation of γ-tocopherol methyltransferase gene contributes to elevated α-tocopherol content in soybean seeds

Directory of Open Access Journals (Sweden)

Abe Jun

2011-11-01

Full Text Available Abstract Background Improvement of α-tocopherol content is an important breeding aim to increase the nutritional value of crops. Several efforts have been conducted to improve the α-tocopherol content in soybean [Glycine max (L. Merr.] through transgenic technology by overexpressing genes related to α-tocopherol biosynthesis or through changes to crop management practices. Varieties with high α-tocopherol content have been identified in soybean germplasms. The heritability of this trait has been characterized in a cross between high α-tocopherol variety Keszthelyi Aproszemu Sarga (KAS and low α-tocopherol variety Ichihime. In this study, the genetic mechanism of the high α-tocopherol content trait of KAS was elucidated. Results Through QTL analysis and fine mapping in populations from a cross between KAS and a Japanese variety Ichihime, we identified γ-TMT3, which encodes γ-tocopherol methyltransferase, as a candidate gene responsible for high α-tocopherol concentration in KAS. Several nucleotide polymorphisms including two nonsynonymous mutations were found in the coding region of γ-TMT3 between Ichihime and KAS, but none of which was responsible for the difference in α-tocopherol concentration. Therefore, we focused on transcriptional regulation of γ-TMT3 in developing seeds and leaves. An F5 line that was heterozygous for the region containing γ-TMT3 was self-pollinated. From among the progeny, plants that were homozygous at the γ-TMT3 locus were chosen for further evaluation. The expression level of γ-TMT3 was higher both in developing seeds and leaves of plants homozygous for the γ-TMT3 allele from KAS. The higher expression level was closely correlated with high α-tocopherol content in developing seeds. We generated transgenic Arabidopsis plants harboring GUS gene under the control of γ-TMT3 promoter from KAS or Ichihime. The GUS activity assay showed that the activity of γ-TMT3 promoter from KAS was higher than that of

Glutathione delays varies as-tocopherol oxidation and subsequent lipid peroxidation in rat liver microsomes

International Nuclear Information System (INIS)

Robey, S.; Mavis, R.

1986-01-01

A method has been developed for in vitro trace radiolabeling of rat liver microsomes with 3 H-α-tocopherol (αT*) which allows virtually complete oxidation of the αT* under oxidizing conditions. The supernatant of a 16,000 xg centrifugation of homogenized rat liver, containing the cytosolic rat liver vitamin E (VE) transfer protein, was incubated with an ethanolic solution of αT* for 10 minutes at 37 0 C. Labeled microsomes were collected in the washed 100,000 xg pellet. Microsomes were then incubated with 30 μM Fe 2+ in an NADPH-generating system, and both production of malondialdehyde (MDA) (a product of lipid peroxidation) and oxidation of αT* were monitored over a time course in the presence and absence of glutathione (GSH). The results indicate virtually complete oxidation of αT* precedes significant membrane lipid peroxidation, and that addition of 5 mM GSH delays both αT* oxidation and subsequent MDA production. This suggests that the previously observed VE-dependent heat labile inhibition of microsomal lipid peroxidation by GSH involves maintaining membrane levels of α-tocopherol

Serum tocopherol levels and vitamin E intake are associated with lung function in the normative aging study.

Science.gov (United States)

Hanson, Corrine; Lyden, Elizabeth; Furtado, Jeremy; Campos, Hannia; Sparrow, David; Vokonas, Pantel; Litonjua, Augusto A

2016-02-01

The results of studies assessing relationships between vitamin E intake and status and lung function are conflicting. This study aimed to evaluate the effect of vitamin E intake and serum levels of tocopherol isoforms on lung function in a cross-sectional sample of 580 men from the Normative Aging Study, a longitudinal aging study. Regression models were used to look at associations of serum tocopherol isoform levels and vitamin E intake with lung function parameters after adjustment for confounders. Vitamin E intake was measured using a food frequency questionnaire and serum levels of γ, α, and δ-tocopherol levels were measured using high-performance liquid chromatography. After adjustment for potential confounders, serum γ-tocopherol had a significant inverse association with forced vital capacity (β = -0.10, p = 0.05). Alpha and δ-tocopherol were not associated with any lung function parameter. After classifying COPD status according to Global Initiative for Obstructive Lung Disease (GOLD) stage criteria, serum levels of δ-tocopherol were lower in participants with more severe COPD (p = 0.01). Serum levels of δ-tocopherol were also lower in participants with greater levels of smoking (p = 0.02). Both vitamin E intake (β = 0.03, p = 0.02; β = 0.03, p = 0.01) and use of vitamin E supplements (β = 0.05, p = 0.03; β = 0.06. p = 0.02) were positively associated with FEV1 and FVC, after adjusting for confounders. Subjects who took vitamin E supplements had significantly higher α-tocopherol levels (p tocopherol levels (p tocopherol and lung function. Copyright © 2015 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.

Computational analysis of protein-protein interfaces involving an alpha helix: insights for terphenyl-like molecules binding.

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Isvoran, Adriana; Craciun, Dana; Martiny, Virginie; Sperandio, Olivier; Miteva, Maria A

2013-06-14

Protein-Protein Interactions (PPIs) are key for many cellular processes. The characterization of PPI interfaces and the prediction of putative ligand binding sites and hot spot residues are essential to design efficient small-molecule modulators of PPI. Terphenyl and its derivatives are small organic molecules known to mimic one face of protein-binding alpha-helical peptides. In this work we focus on several PPIs mediated by alpha-helical peptides. We performed computational sequence- and structure-based analyses in order to evaluate several key physicochemical and surface properties of proteins known to interact with alpha-helical peptides and/or terphenyl and its derivatives. Sequence-based analysis revealed low sequence identity between some of the analyzed proteins binding alpha-helical peptides. Structure-based analysis was performed to calculate the volume, the fractal dimension roughness and the hydrophobicity of the binding regions. Besides the overall hydrophobic character of the binding pockets, some specificities were detected. We showed that the hydrophobicity is not uniformly distributed in different alpha-helix binding pockets that can help to identify key hydrophobic hot spots. The presence of hydrophobic cavities at the protein surface with a more complex shape than the entire protein surface seems to be an important property related to the ability of proteins to bind alpha-helical peptides and low molecular weight mimetics. Characterization of similarities and specificities of PPI binding sites can be helpful for further development of small molecules targeting alpha-helix binding proteins.

21 CFR 582.5890 - Tocopherols.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Tocopherols. 582.5890 Section 582.5890 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS... 1 § 582.5890 Tocopherols. (a) Product. Tocopherols. (b) Conditions of use. This substance is...

21 CFR 182.3890 - Tocopherols.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Tocopherols. 182.3890 Section 182.3890 Food and... CONSUMPTION (CONTINUED) SUBSTANCES GENERALLY RECOGNIZED AS SAFE Chemical Preservatives § 182.3890 Tocopherols. (a) Product. Tocopherols. (b) Conditions of use. This substance is generally recognized as safe when...

21 CFR 582.3890 - Tocopherols.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Tocopherols. 582.3890 Section 582.3890 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS... Tocopherols. (a) Product. Tocopherols. (b) Conditions of use. This substance is generally recognized as safe...

Alpha-Tocopherol Reduces Brain Edema and Protects Blood-Brain Barrier Integrity following Focal Cerebral Ischemia in Rats.

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Haghnejad Azar, Adel; Oryan, Shahrbanoo; Bohlooli, Shahab; Panahpour, Hamdollah

2017-01-01

This study was conducted to examine the neuroprotective effects of α-tocopherol against edema formation and disruption of the blood-brain barrier (BBB) following transient focal cerebral ischemia in rats. Ninety-six male Sprague-Dawley rats were divided into 3 major groups (n = 32 in each), namely the sham, and control and α-tocopherol-treated (30 mg/kg) ischemic groups. Transient focal cerebral ischemia (90 min) was induced by occlusion of the left middle cerebral artery. At the end of the 24-hour reperfusion period, the animals were randomly selected and used for 4 investigations (n = 8) in each of the 3 main groups: (a) assessment of neurological score and measurement of infarct size, (b) detection of brain edema formation by the wet/dry method, (c) evaluation of BBB permeability using the Evans blue (EB) extravasation technique, and (d) assessment of the malondialdehyde (MDA) and reduced glutathione (GSH) concentrations using high-performance liquid chromatography methods. Induction of cerebral ischemia in the control group produced extensive brain edema (brain water content 83.8 ± 0.11%) and EB leakage into brain parenchyma (14.58 ± 1.29 µg/g) in conjunction with reduced GSH and elevated MDA levels (5.86 ± 0.31 mmol/mg and 63.57 ± 5.42 nmol/mg, respectively). Treatment with α-tocopherol significantly lowered brain edema formation and reduced EB leakage compared with the control group (p < 0.001, 80.1 ± 0.32% and 6.66 ± 0.87 µg/g, respectively). Meanwhile, treatment with α-tocopherol retained tissue GSH levels and led to a lower MDA level (p < 0.01, 10.17 ± 0.83 mmol/mg, and p < 0.001, 26.84 ± 4.79 nmol/mg, respectively). Treatment with α-tocopherol reduced ischemic edema formation and produced protective effects on BBB function following ischemic stroke occurrence. This effect could be through increasing antioxidant activity. © 2016 S. Karger AG, Basel.

21 CFR 182.8890 - Tocopherols.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Tocopherols. 182.8890 Section 182.8890 Food and... CONSUMPTION (CONTINUED) SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients § 182.8890 Tocopherols. (a) Product. Tocopherols. (b) Conditions of use. This substance is generally recognized as safe when used in accordance...

δ-Tocopherol Is More Active than α- or γ-Tocopherol in Inhibiting Lung Tumorigenesis In Vivo

OpenAIRE

Li, Guang Xun; Lee, Mao-Jung; Liu, Anna Ba; Yang, Zhihong; Lin, Yong; Shih, Weichung Joe; Yang, Chung S.

2011-01-01

In contrast to strong epidemiologic, preclinical, and secondary clinical evidence for vitamin E (tocopherols) in reducing cancer risk, large-scale clinical cancer-prevention trials of α-tocopherol have been negative. This vexing contrast helped spur substantial preclinical efforts to better understand and improve the antineoplastic activity of tocopherol through, for example, the study of different tocopherol forms. We previously showed that the γ-tocopherol–rich mixture (γ-TmT) effectively i...

Alpha-1-antitrypsin studies: canine serum and canine surfactant protein

International Nuclear Information System (INIS)

Tuttle, W.C.; Slauson, D.O.; Dahlstrom, M.; Gorman, C.

1974-01-01

Canine serum alpha-1-antitrypsin was isolated by gel filtration and affinity chromatography and characterized by polyacrylamide gel electrophoresis and immunoelectrophoresis. Measurement of the trypsin inhibitory capacity of the separated protein indicated a ninefold concentration of functional trypsin inhibitor during the isolation procedure. Electrophoresis demonstrated the presence of a single protein with alpha-globulin mobility and a molecular weight near that of human alpha-1-antitrypsin. The trypsin inhibitory capacity of pulmonary surfactant protein from five Beagle dogs was measured, related to total surfactant protein concentration, and compared with similar measurements on whole serum from the same animals. Results indicated a variable concentration of trypsin inhibitor in the canine pulmonary surfactant protein. However, the concentration in the surfactant protein was always significantly higher than that in the corresponding serum sample. Preliminary experiments designed to separate the trypsin inhibitory fraction(s) from the other surfactant proteins by gel filtration chromatography indicated that the trypsin inhibitor was probably a single protein with a molecular weight near that of alpha-1-antitrypsin. (U.S.)

Alpha-tocopherol succinate- and AMD3100-mobilized progenitors mitigate radiation combined injury in mice

International Nuclear Information System (INIS)

Singh, Vijay K.; Wise, Stephen Y.; Fatanmi, Oluseyi O.; Beattie, Lindsay A.; Ducey, Elizabeth J.; Seed, Thomas M.

2014-01-01

The purpose of this study was to elucidate the role of alpha-tocopherol succinate (TS)- and AMD3100-mobilized progenitors in mitigating combined injury associated with acute radiation exposure in combination with secondary physical wounding. CD2F1 mice were exposed to high doses of cobalt-60 gamma-radiation and then transfused intravenously with 5 million peripheral blood mononuclear cells (PBMCs) from TS- and AMD3100-injected mice after irradiation. Within 1 h after irradiation, mice were exposed to secondary wounding. Mice were observed for 30 d after irradiation and cytokine analysis was conducted by multiplex Luminex assay at various time-points after irradiation and wounding. Our results initially demonstrated that transfusion of TS-mobilized progenitors from normal mice enhanced survival of acutely irradiated mice exposed 24 h prior to transfusion to supralethal doses (11.5–12.5 Gy) of 60 Co gamma-radiation. Subsequently, comparable transfusions of TS-mobilized progenitors were shown to significantly mitigate severe combined injuries in acutely irradiated mice. TS administered 24 h before irradiation was able to protect mice against combined injury as well. Cytokine results demonstrated that wounding modulates irradiation-induced cytokines. This study further supports the conclusion that the infusion of TS-mobilized progenitor-containing PBMCs acts as a bridging therapy in radiation-combined-injury mice. We suggest that this novel bridging therapeutic approach involving the infusion of TS-mobilized hematopoietic progenitors following acute radiation exposure or combined injury might be applicable to humans. (author)

Supplementation with RRR- or all-rac-α-Tocopherol Differentially Affects the α-Tocopherol Stereoisomer Profile in the Milk and Plasma of Lactating Women.

Science.gov (United States)

Gaur, Shashank; Kuchan, Matthew J; Lai, Chron-Si; Jensen, Soren K; Sherry, Christina L

2017-07-01

Background: The naturally occurring α-tocopherol stereoisomer RRR- α-tocopherol is known to be more bioactive than synthetic α-tocopherol ( all-rac -α-tocopherol). However, the influence of this difference on the α-tocopherol stereoisomer profile of human milk is not understood. Objective: We investigated whether supplemental RRR- α-tocopherol or all-rac -α-tocopherol differentially affected the distribution of α-tocopherol stereoisomers in milk and plasma from lactating women. Methods: Eighty-nine lactating women aged 19-40 y and with a body mass index (in kg/m 2 ) ≤30 were randomly assigned at 4-6 wk postpartum to receive a daily supplement containing 45.5 mg all-rac -α-tocopherol acetate (ARAC), 22.8 mg all-rac -α-tocopherol acetate + 20.1 mg RRR -α-tocopherol (MIX), or 40.2 mg RRR- α-tocopherol (RRR). Milk and plasma were analyzed for α-tocopherol structural isomers and α-tocopherol stereoisomers at baseline and after 6 wk supplementation with the use of chiral HPLC. Results: There were no significant treatment group or time-dependent changes in milk or plasma α, γ, or δ-tocopherol. RRR- α-tocopherol was the most abundant stereoisomer in both milk and plasma in each group. Supplementation changed both milk and plasma percentage RRR- α-tocopherol (RRR > MIX > ARAC) ( P tocopherol (ARAC > MIX > RRR) ( P tocopherol increased in milk (mean ± SEM: 78% ± 2.3% compared with 82% ± 1.7%) ( P tocopherol decreased in the MIX and ARAC groups (MIX, P tocopherol stereoisomers increased (MIX, P tocopherol stereoisomers ( P tocopherol was positively correlated at baseline ( r = 0.67; P tocopherol supplementation strategy differentially affected the α-tocopherol milk and plasma stereoisomer profile in lactating women. RRR- α-tocopherol increased milk and plasma percentage RRR- α-tocopherol, whereas all-rac -α-tocopherol acetate reduced these percentages. Because RRR- α-tocopherol is the most bioactive stereoisomer, investigating the impact of

Isolation and expression of a novel chick G-protein cDNA coding for a G alpha i3 protein with a G alpha 0 N-terminus.

OpenAIRE

Kilbourne, E J; Galper, J B

1994-01-01

We have cloned cDNAs coding for G-protein alpha subunits from a chick brain cDNA library. Based on sequence similarity to G-protein alpha subunits from other eukaryotes, one clone was designated G alpha i3. A second clone, G alpha i3-o, was identical to the G alpha i3 clone over 932 bases on the 3' end. The 5' end of G alpha i3-o, however, contained an alternative sequence in which the first 45 amino acids coded for are 100% identical to the conserved N-terminus of G alpha o from species such...

21 CFR 184.1890 - α-Tocopherols.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 3 2010-04-01 2009-04-01 true α-Tocopherols. 184.1890 Section 184.1890 Food and... Substances Affirmed as GRAS § 184.1890 α-Tocopherols. (a) The α-tocopherols that are the subject of this GRAS affirmation regulation are limited to the following: (1) d-α-Tocopherol (CAS Reg. No. 59-02-9) is the chemical...

Gamma (γ) tocopherol upregulates peroxisome proliferator activated receptor (PPAR) gamma (γ) expression in SW 480 human colon cancer cell lines

Science.gov (United States)

Campbell, Sharon E; Stone, William L; Whaley, Sarah G; Qui, Min; Krishnan, Koyamangalath

2003-01-01

Background Tocopherols are lipid soluble antioxidants that exist as eight structurally different isoforms. The intake of γ-tocopherol is higher than α-tocopherol in the average US diet. The clinical results of the effects of vitamin E as a cancer preventive agent have been inconsistent. All published clinical trials with vitamin E have used α-tocopherol. Recent epidemiological, experimental and molecular studies suggest that γ-tocopherol may be a more potent chemopreventive form of vitamin E compared to the more-studied α-tocopherol. γ-Tocopherol exhibits differences in its ability to detoxify nitrogen dioxide, growth inhibitory effects on selected cancer cell lines, inhibition of neoplastic transformation in embryonic fibroblasts, and inhibition of cyclooxygenase-2 (COX-2) activity in macrophages and epithelial cells. Peroxisome proliferator activator receptor γ (PPARγ) is a promising molecular target for colon cancer prevention. Upregulation of PPARγ activity is anticarcinogenic through its effects on downstream genes that affect cellular proliferation and apoptosis. The thiazolidine class of drugs are powerful PPARγ ligands. Vitamin E has structural similarity to the thiazolidine, troglitazone. In this investigation, we tested the effects of both α and γ tocopherol on the expression of PPARγ mRNA and protein in SW 480 colon cancer cell lines. We also measured the intracellular concentrations of vitamin E in SW 480 colon cancer cell lines. Results We have discovered that the α and γ isoforms of vitamin E upregulate PPARγ mRNA and protein expression in the SW480 colon cancer cell lines. γ-Tocopherol is a better modulator of PPARγ expression than α-tocopherol at the concentrations tested. Intracellular concentrations increased as the vitamin E concentration added to the media was increased. Further, γ-tocopherol-treated cells have higher intracellular tocopherol concentrations than those treated with the same concentrations of α-tocopherol

Gamma (γ) tocopherol upregulates peroxisome proliferator activated receptor (PPAR) gamma (γ) expression in SW 480 human colon cancer cell lines

International Nuclear Information System (INIS)

Campbell, Sharon E; Stone, William L; Whaley, Sarah G; Qui, Min; Krishnan, Koyamangalath

2003-01-01

Tocopherols are lipid soluble antioxidants that exist as eight structurally different isoforms. The intake of γ-tocopherol is higher than α-tocopherol in the average US diet. The clinical results of the effects of vitamin E as a cancer preventive agent have been inconsistent. All published clinical trials with vitamin E have used α-tocopherol. Recent epidemiological, experimental and molecular studies suggest that γ-tocopherol may be a more potent chemopreventive form of vitamin E compared to the more-studied α-tocopherol. γ-Tocopherol exhibits differences in its ability to detoxify nitrogen dioxide, growth inhibitory effects on selected cancer cell lines, inhibition of neoplastic transformation in embryonic fibroblasts, and inhibition of cyclooxygenase-2 (COX-2) activity in macrophages and epithelial cells. Peroxisome proliferator activator receptor γ (PPARγ) is a promising molecular target for colon cancer prevention. Upregulation of PPARγ activity is anticarcinogenic through its effects on downstream genes that affect cellular proliferation and apoptosis. The thiazolidine class of drugs are powerful PPARγ ligands. Vitamin E has structural similarity to the thiazolidine, troglitazone. In this investigation, we tested the effects of both α and γ tocopherol on the expression of PPARγ mRNA and protein in SW 480 colon cancer cell lines. We also measured the intracellular concentrations of vitamin E in SW 480 colon cancer cell lines. We have discovered that the α and γ isoforms of vitamin E upregulate PPARγ mRNA and protein expression in the SW480 colon cancer cell lines. γ-Tocopherol is a better modulator of PPARγ expression than α-tocopherol at the concentrations tested. Intracellular concentrations increased as the vitamin E concentration added to the media was increased. Further, γ-tocopherol-treated cells have higher intracellular tocopherol concentrations than those treated with the same concentrations of α-tocopherol. Our data suggest that

Inhibitory effects of different forms of tocopherols, tocopherol phosphates, and tocopherol quinones on growth of colon cancer cells.

Science.gov (United States)

Dolfi, Sonia C; Yang, Zhihong; Lee, Mao-Jung; Guan, Fei; Hong, Jungil; Yang, Chung S

2013-09-11

Tocopherols are the major source of dietary vitamin E. In this study, the growth inhibitory effects of different forms of tocopherols (T), tocopheryl phosphates (TP), and tocopherol quinones (TQ) on human colon cancer HCT116 and HT29 cells were investigated. δ-T was more active than γ-T in inhibiting colon cancer cell growth, decreasing cancer cell colony formation, and inducing apoptosis; however, α-T was rather ineffective. Similarly, the rate of cellular uptake also followed the ranking order δ-T > γ-T ≫ α-T. TP and TQ generally had higher inhibitory activities than their parent compounds. Interestingly, the γ forms of TP and TQ were more active than the δ forms in inhibiting cancer cell growth, whereas the α forms were the least effective. The potencies of γ-TQ and δ-TQ (showing IC50 values of ∼0.8 and ∼2 μM on HCT116 cells after a 72 h incubation, respectively) were greater than 100-fold and greater than 20-fold higher, respectively, than those of their parent tocopherols. Induction of cancer cell apoptosis by δ-T, γ-TP, and γ-TQ was characterized by the cleavage of caspase 3 and PARP1 and DNA fragmentation. These studies demonstrated the higher growth inhibitory activity of δ-T than γ-T, the even higher activities of the γ forms of TP and TQ, and the ineffectiveness of the α forms of tocopherol and their metabolites against colon cancer cells.

Incorporation of Sunflower Oil and d-alpha-tocopherol Effect on Mechanical Properties and Permeability of Corn Starch Composite Edible Film

Directory of Open Access Journals (Sweden)

Pramono Putro Utomo

2015-06-01

Full Text Available Corn starch-based films are inherently brittle and lack the necessary mechanical integrity for conventional packaging. However, the incorporation of additives can potentially improve the mechanical properties and processability of starch films. In this work sunflower oil (SO and vitamin E (d-alpha-tocopherol at three levels each (0.05%, 0.1% and 0.15% (w/vtotal and (0.18%, 0.36% and 0.54% (w/vtotal were incorporated into corn starch films using a solution casting method to improve the mechanical and water vapour transmission rate (WVTR properties. The addition of SO and vitamin E increased elongation at break of starch-based film while decreased tensile strength and WVTR of starch-based film. The best edible film obtained on addition of sunflower oil concentration of 0.15% and 0.54%, vitamin E with a value of 0.121 mm thickness, tensile strength of 65.38 kg/cm2, elongation at break 14.17% and WVTR 1144 g/m2 24 hours.

Factors Affecting Tocopherol Concentrations in Soybean Seeds.

Science.gov (United States)

Carrera, Constanza S; Seguin, Philippe

2016-12-21

Soybean seeds contain several health-beneficial compounds, including tocopherols, which are used by the nutraceutical and functional food industries. Soybean tocopherol concentrations are, however, highly variable. Large differences observed in tocopherol concentrations among soybean genotypes together with the relatively simple biosynthetic pathway involving few genes support the feasibility of selecting for high-tocopherol soybean. Tocopherol concentrations are also highly influenced by environmental factors and field management. Temperature during seed filling and soil moisture appear to be the main factors affecting tocopherol concentrations; other factors such as soil fertility and solar radiation also affect concentrations and composition. Field management decisions including seeding date, row spacing, irrigation, and fertilization also affect tocopherols. Knowledge of factors affecting soybean tocopherols is essential to develop management strategies that will lead to the production of seeds with consistent target concentrations that will meet the needs of the nutraceutical and functional food industries.

Supplementation of α-Tocopherol Attenuates Minerals Disturbance, Oxidative Stress and Apoptosis Occurring in Favism.

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Koriem, Khaled M M; Arbid, Mahmoud S; Gomaa, Nawal E

2017-10-01

The favism is a metabolic disease that characterized with an acute hemolytic anemia where α-tocopherol is a type of tocopherol accumulated inside the human body. The objective of such a study was established to evaluate the effect of α-tocopherol in favism disorders. A total of 75 human cases were divided into 5 groups as follow; group 1 normal cases without any treatment and group 2 normal cases orally administrated α-tocopherol (200 mg/kg) once a day over 30 days period. Group 3 favism patients without any treatment. Groups 4 and 5 favism patients orally administrated 100 and 200 mg α-tocopherol/kg, respectively once a day over 30 days period. The results obtained revealed that oral administration of α-tocopherol into normal cases over 30 days period did not induce any biological change. In favism, hemoglobin, hematocrit, red and white blood cells, serum glucose, glucose-6-phosphate dehydrogenase, total protein, albumin, globulin, aspartate and alanine aminotransferases, blood glutathione, superoxide dismutase, glutathione peroxidase and serum calcium, phosphorous, sodium, potassium and chloride levels were significantly decreased. On the other hand, serum alkaline phosphatase, bilirubin, selenium, zinc, manganese, copper and iron, malondialdehyde levels showed significant increase in favism. Supplementation with α-tocopherol into favism restores all the above mentioned parameters to approach the normal levels. Also, α-tocopherol has anti-apoptotic effect in favism. In conclusion, α-tocopherol attenuates minerals disturbance, oxidative stress and apoptosis occurring in favism.

Reduced Fragment Diversity for Alpha and Alpha-Beta Protein Structure Prediction using Rosetta.

Science.gov (United States)

Abbass, Jad; Nebel, Jean-Christophe

2017-01-01

Protein structure prediction is considered a main challenge in computational biology. The biannual international competition, Critical Assessment of protein Structure Prediction (CASP), has shown in its eleventh experiment that free modelling target predictions are still beyond reliable accuracy, therefore, much effort should be made to improve ab initio methods. Arguably, Rosetta is considered as the most competitive method when it comes to targets with no homologues. Relying on fragments of length 9 and 3 from known structures, Rosetta creates putative structures by assembling candidate fragments. Generally, the structure with the lowest energy score, also known as first model, is chosen to be the "predicted one". A thorough study has been conducted on the role and diversity of 3-mers involved in Rosetta's model "refinement" phase. Usage of the standard number of 3-mers - i.e. 200 - has been shown to degrade alpha and alpha-beta protein conformations initially achieved by assembling 9-mers. Therefore, a new prediction pipeline is proposed for Rosetta where the "refinement" phase is customised according to a target's structural class prediction. Over 8% improvement in terms of first model structure accuracy is reported for alpha and alpha-beta classes when decreasing the number of 3- mers. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Mannan-binding protein forms complexes with alpha-2-macroglobulin. A protein model for the interaction

DEFF Research Database (Denmark)

Storgaard, P; Holm Nielsen, E; Skriver, E

1995-01-01

We report that alpha-2-macroglobulin (alpha 2M) can form complexes with a high molecular weight porcine mannan-binding protein (pMBP-28). The alpha 2M/pMBP-28 complexes was isolated by PEG-precipitation and affinity chromatography on mannan-Sepharose, protein A-Sepharose and anti-IgM Sepharose......-PAGE, which reacted with antibodies against alpha 2M and pMBP-28, respectively, in Western blotting. Furthermore, alpha 2M/pMBP-28 complexes were demonstrated by electron microscopy. Fractionation of pMBP-containing D-mannose eluate from mannan-Sepharose on Superose 6 showed two protein peaks which reacted...... with anti-C1 s antibodies in ELISA, one of about 650-800 kDa, which in addition contained pMBP-28 and anti-alpha 2M reactive material, the other with an M(r) of 100-150 kDa. The latter peak revealed rhomboid molecules (7 x 15 nm) in the electron microscope and a 67 kDa band in SDS-PAGE under reducing...

The effect of γ-tocopherol on proliferation, integrin expression, adhesion, and migration of human glioma cells

International Nuclear Information System (INIS)

Samandari, Elika; Visarius, Theresa; Zingg, Jean-Marc; Azzi, Angelo

2006-01-01

The effect of vitamin E on proliferation, integrin expression, adhesion, and migration in human glioma cells has been studied. γ-tocopherol at 50 μM concentration exerted more inhibitory effect than α-tocopherol at the same concentration on glioma cell proliferation. Integrin α5 and β1 protein levels were increased upon both α- and γ-tocopherol treatments. In parallel, an increase in the α5β1 heterodimer cell surface expression was observed. The tocopherols inhibited glioma cell-binding to fibronectin where γ-tocopherol treatment induced glioma cell migration. Taken together, the data reported here are consistent with the notion that the inhibition of glioma cell proliferation induced by tocopherols may be mediated, at least in part, by an increase in integrin α5 and β1 expression. Cell adhesion is also negatively affected by tocopherols, despite a small increase in the surface appearance of the α5β1 heterodimer. Cell migration is stimulated by γ-tocopherol. It is concluded that α5 and β1 integrin expression and surface appearance are not sufficient to explain all the observations and that other integrins or in general other factors may be associated with these events

Tocopherol from seeds of Cucurbita pepo against diabetes: validation by in vivo experiments supported by computational docking.

Science.gov (United States)

Bharti, Sudhanshu Kumar; Kumar, Amit; Sharma, Neeraj Kumar; Prakash, Om; Jaiswal, Sudhir Kumar; Krishnan, Supriya; Gupta, Ashok Kumar; Kumar, Awanish

2013-11-01

Tocopherol from raw pumpkin seeds has been reported to be effective in the alleviation of diabetes through its antioxidant activities. This study evaluates the antidiabetic activities of the tocopherol fraction of raw seeds of Cucurbita pepo L. (CPSE) in a diabetic rat model. In addition, the putative action mechanisms of its botanicals were computationally investigated. Seed water activity (Aw) was assessed. Tocopherol was extracted and quantified from raw seed oil. The effect of CPSE was studied in poloxamer-407 (PX-407)-induced type 2 diabetic Wistar rats. Glycemic, insulinemic, and lipid profiles, as well as lipid peroxidation status, were evaluated. Glucagon like peptide-1 (GLP-1) content in the cecum was evaluated and histopathological analysis of the pancreas was performed. Further, HYBRID and FRED docking were performed for 10 documented CPSE botanicals, for putative action mechanisms concerning three proteins [protein-tyrosine phosphatase 1B (PTP-1B), peroxisome proliferator-activated receptor gamma (PPAR-γ), and dipeptidyl peptidase IV (DPP-IV)] known to have diabetic therapeutic potential. The Aw of raw seeds was found to be 0.544 ± 0.002. Using tocopherol standards, HPLC determination of CPSE revealed the presence of tocopherol isomers (α, β, γ, and δ). The tocopherol content was found to be 107.4 ± 2.9 mg/100 g of CPSE. When compared to diabetic control (DC) rats, the CPSE-treated diabetic rats presented a significant amelioration of glycemia, insulinemia, and lipid dysmetabolism. A remarkable reduction in oxidative markers and improved cecal and pancreatic characteristics were also observed. Tocopherol isomers have shown a considerable interaction potential with the aforesaid proteins in docking. The results provide pharmacological evidence of CPSE as an antihyperglycemic mediated by the interaction of various botanicals with multiple targets operating in diabetes mellitus (DM).

Conformational analysis of a Chlamydia-specific disaccharide {alpha}-Kdo-(2{sup {yields}}8)-{alpha}-Kdo-(2{sup {yields}}O)-allyl in aqueous solution and bound to a monoclonal antibody: Observation of intermolecular transfer NOEs

Energy Technology Data Exchange (ETDEWEB)

Sokolowski, Tobias; Haselhorst, Thomas; Scheffler, Karoline [Medizinische Universitaet, Institut fuer Chemie (Germany); Weisemann, Ruediger [Bruker Analytik GmbH, Silberstreifen (Germany); Kosma, Paul [Institut fuer Chemie der Universitaet fuer Bodenkultur Wien (Austria); Brade, Helmut; Brade, Lore [Forschungszentrum Borstel, Zentrum fuer Medizin und Biowissenschaften Parkallee 22 (Germany); Peters, Thomas [Medizinische Universitaet, Institut fuer Chemie (Germany)

1998-07-15

The disaccharide {alpha}-Kdo-(2{sup {yields}}8)-{alpha}-Kdo (Kdo: 3-deoxy-d-manno-oct-2-ulosonic acid) represents a genus-specific epitope of the lipopolysaccharide of the obligate intracellular human pathogen Chlamydia. The conformation of the synthetically derived disaccharide {alpha}-Kdo-(2{sup {yields}}8)-{alpha}-Kdo-(2{sup {yields}}O)-allyl was studied in aqueous solution, and complexed to a monoclonal antibody S25-2. Various NMR experiments based on the detection of NOEs (or transfer NOEs) and ROEs (or transfer ROEs) were performed. A major problem was the extensive overlap of almost all {sup 1}H NMR signals of {alpha}-Kdo-(2{sup {yields}}8)-{alpha}-Kdo-(2{sup {yields}}O)-allyl. To overcome this difficulty, HMQC-NOESY and HMQC-trNOESY experiments were employed. Spin diffusion effects were identified using trROESY experiments, QUIET-trNOESY experiments and MINSY experiments. It was found that protein protons contribute to the observed spin diffusion effects. At 800 MHz, intermolecular trNOEs were observed between ligand protons and aromatic protons in the antibody binding site. From NMR experiments and Metropolis Monte Carlo simulations, it was concluded that {alpha}-Kdo-(2{sup {yields}}8)-{alpha}-Kdo-(2{sup {yields}}O)-allyl in aqueous solution exists as a complex conformational mixture. Upon binding to the monoclonal antibody S25-2, only a limited range of conformations is available to {alpha}-Kdo-(2{sup {yields}}8)-{alpha}-Kdo-(2{sup {yields}}O)-allyl. These possible bound conformations were derived from a distance geometry analysis using transfer NOEs as experimental constraints. It is clear that a conformation is selected which lies within a part of the conformational space that is highly populated in solution. This conformational space also includes the conformation found in the crystal structure. Our results provide a basis for modeling studies of the antibody-disaccharide complex.

Tocopherols in Sunflower Seedlings under Light and Dark Conditions.

Science.gov (United States)

del Moral, Lidia; Pérez-Vich, Begoña; Velasco, Leonardo

2015-01-01

The objective of this study was to evaluate the dynamics of tocopherols in cotyledons and radicles from sunflower seeds with high and low total tocopherol content, mainly in the α-tocopherol form, and from seeds with increased proportions of β-, γ-, and δ-tocopherol, both under dark and light conditions. Tocopherol content was measured every 24 h from 1 to 12 days after sowing. In all cases, the content of individual tocopherol forms in the cotyledons and radicles was reduced along the sampling period, which was more pronounced under light conditions. The presence of light had a slightly greater effect on α- and γ-tocopherol than on β- and δ-tocopherol. A marked light effect was also observed on total tocopherol content, with light promoting the reduction of tocopherol content in cotyledons and radicles. The study revealed only slight differences in the patterns of tocopherol losses in lines with different tocopherol profiles, both under dark and light conditions, which suggested that the partial replacement of α-tocopherol by other tocopherol forms had no great impact on the protection against oxidative damage in seedlings.

Tocopherol in irradiation of experimental neoplasms

International Nuclear Information System (INIS)

Kaagerud, A.; Peterson, H.-I.

1981-01-01

The influence of tocopherol, administered intramuscularly in different single doses, on the effect of local irradiation of a transplanted rat sarcoma was investigated. Tocopherol in doses of 5, 25 or 50 mg/100 g body weight enhanced significantly the tumour growth retardation induced by irradiation. Tocopherol in a dose of 100 mg/100 g body weight as a placebo preparation had no similar effect. The influence of tocopherol administered intramuscularly or orally in identical doses was similar. (Auth.)

Both alpha- and ß-Carotene, but Not Tocopherols and Vitamin C, are Inversely Related to 15-Year Cardiovascular Mortality in Dutch Elderly Men 1,2

NARCIS (Netherlands)

Buijsse, B.; Feskens, E.J.M.; Kwape, L.; Kok, F.J.; Kromhout, D.

2008-01-01

The role of ß-carotene, -tocopherol, and vitamin C in the prevention of cardiovascular diseases (CVD) is controversial. Prospective studies on -tocopherol and carotenoids other than ß-carotene are sparse. We assessed relations between the intake of different carotenoids, - and -tocopherol, and

Electron transfer in proteins

DEFF Research Database (Denmark)

Farver, O; Pecht, I

1991-01-01

Electron migration between and within proteins is one of the most prevalent forms of biological energy conversion processes. Electron transfer reactions take place between active centers such as transition metal ions or organic cofactors over considerable distances at fast rates and with remarkable...... specificity. The electron transfer is attained through weak electronic interaction between the active sites, so that considerable research efforts are centered on resolving the factors that control the rates of long-distance electron transfer reactions in proteins. These factors include (in addition......-containing proteins. These proteins serve almost exclusively in electron transfer reactions, and as it turns out, their metal coordination sites are endowed with properties uniquely optimized for their function....

/sup 58,60,62/Ni (. cap alpha. ,p) three--nucleon transfer reactions and. cap alpha. optical potential ambiguities

Energy Technology Data Exchange (ETDEWEB)

Yuanda, Wang; Xiuming, Bao; Zhiqiang, Mao; Rongfang, Yuan; Keling, Wen; Binyin, Huang; Zhifu, Wang; Shuming, Li; Jianan, Wang; Zuxun, Sun; others, and

1985-11-01

The differential cross sections are measured using 26.0 MeV ..cap alpha.. particle for /sup 58,62/Ni(..cap alpha.., ..cap alpha..) /sup 58,62/Ni and /sup 58,62/Ni(..cap alpha..,p) /sup 61,65/Cu reactions as well as 25.4 MeV ..cap alpha.. particle for /sup 60/Ni(..cap alpha.., ..cap alpha..)/sup 69/Ni and /sup 60/Ni(..cap alpha.., p)/sup 63/Cu reactions. Consistent calculations with optical model and ZR DWBA are made for (..cap alpha.., ..cap alpha..) and (..cap alpha.., p) reactions by using of single, two, three and four nucleon optical potential parameters. For elastic scattering due to the ..cap alpha.. optical potential ambiguities, all the above optical potential can reproduce the experimental angular distributions. However, the single, two and three nucleon potential, including the Baird's mass systematics and the Chang's energy systematics of ..cap alpha.. potentials, obviously can not provide a reasonable fitting with the (..cap alpha..,p) reaction experimental data. Only the results from the four nucleon potential is in good agreement with the (..cap alpha..,p) reaction experimental data. This reveals that in the ..cap alpha..-particle induced transfer reactions, the real depth of the ..cap alpha..-nucleus optical potential should be rather deep.

Electrophoretic transfer protein zymography.

Science.gov (United States)

Pan, Daniel; Hill, Adam P; Kashou, Anthony; Wilson, Karl A; Tan-Wilson, Anna

2011-04-15

Zymography detects and characterizes proteolytic enzymes by electrophoresis of protease-containing samples into a nonreducing sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) gel containing a copolymerized protein substrate. The usefulness of zymography for molecular weight determination and proteomic analysis is hampered by the fact that some proteases exhibit slower migration through a gel that contains substrate protein. This article introduces electrophoretic transfer protein zymography as one solution to this problem. In this technique, samples containing proteolytic enzymes are first resolved in nonreducing SDS-PAGE on a gel without protein substrate. The proteins in the resolving gel are then electrophoretically transferred to a receiving gel previously prepared with a copolymerized protein substrate. The receiving gel is then developed as a zymogram to visualize clear or lightly stained bands in a dark background. Band intensities are linearly related to the amount of protease, extending the usefulness of the technique so long as conditions for transfer and development of the zymogram are kept constant. Conditions of transfer, such as the pore sizes of resolving and receiving gels and the transfer time relative to the molecular weight of the protease, are explored. Copyright © 2011 Elsevier Inc. All rights reserved.

Effects of tocopherols on oxidative stability of margarine

International Nuclear Information System (INIS)

Azizkhani, M.; Kamkar, A.; Nejad, A.S.M.

2011-01-01

Tocopherols are the most important natural antioxidants which are now added to edible oils. Each individual tocopherol (a, beta and gamma) was added to the oil phase of margarine in 0 (control), 100, 250, and 500 ppm. Anti oxidative activity was evaluated through oven test (at 60 +- 1 deg. C in 5 days and measuring peroxide value and anisidine value) and Ransimat test (110 +- 1 deg. C). Anti oxidative activity increased progressively as concentration of gamma-tocopherol increased. As the concentration of gamma-tocopherol increased from 0 to 100, and 250 ppm, oxidation of oil phase decreased. At 500 ppm, a-tocopherol acted as a prooxidant and gamma-tocopherol did not have any noticable effect, but gamma-tocopherol acted as an antioxidant. The order of anti oxidative activity of tocopherols was: a- < beta- < gamma-. (author)

Vitamin E isomer δ-tocopherol enhances the efficiency of neural stem cell differentiation via L-type calcium channel.

Science.gov (United States)

Deng, Sihao; Hou, Guoqiang; Xue, Zhiqin; Zhang, Longmei; Zhou, Yuye; Liu, Chao; Liu, Yanqing; Li, Zhiyuan

2015-01-12

The effects of the vitamin E isomer δ-tocopherol on neural stem cell (NSC) differentiation have not been investigated until now. Here we investigated the effects of δ-tocopherol on NSC neural differentiation, maturation and its possible mechanisms. Neonatal rat NSCs were grown in suspended neurosphere cultures, and were identified by their expression of nestin protein and their capacity for self-renewal. Treatment with a low concentration of δ-tocopherol induced a significant increase in the percentage of β-III-tubulin-positive cells. δ-Tocopherol also stimulated morphological maturation of neurons in culture. We further observed that δ-tocopherol stimulation increased the expression of voltage-dependent Ca(2+) channels. Moreover, a L-type specific Ca(2+) channel blocker verapamil reduced the percentage of differentiated neurons after δ-tocopherol treatment, and blocked the effects of δ-tocopherol on NSC differentiation into neurons. Together, our study demonstrates that δ-tocopherol may act through elevation of L-type calcium channel activity to increase neuronal differentiation. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Quercetin suppresses hypoxia-induced accumulation of hypoxia-inducible factor-1alpha (HIF-1alpha) through inhibiting protein synthesis.

Science.gov (United States)

Lee, Dae-Hee; Lee, Yong J

2008-10-01

Quercetin, a ubiquitous bioactive plant flavonoid, has been shown to inhibit the proliferation of cancer cells and induce the accumulation of hypoxia-inducible factor-1alpha (HIF-1alpha) in normoxia. In this study, under hypoxic conditions (1% O(2)), we examined the effect of quercetin on the intracellular level of HIF-1alpha and extracellular level of vascular endothelial growth factor (VEGF) in a variety of human cancer cell lines. Surprisingly, we observed that quercetin suppressed the HIF-1alpha accumulation during hypoxia in human prostate cancer LNCaP, colon cancer CX-1, and breast cancer SkBr3 cells. Quercetin treatment also significantly reduced hypoxia-induced secretion of VEGF. Suppression of HIF-1alpha accumulation during treatment with quercetin in hypoxia was not prevented by treatment with 26S proteasome inhibitor MG132 or PI3K inhibitor LY294002. Interestingly, hypoxia (1% O(2)) in the presence of 100 microM quercetin inhibited protein synthesis by 94% during incubation for 8 h. Significant quercetin concentration-dependent inhibition of protein synthesis and suppression of HIF-1alpha accumulation were observed under hypoxic conditions. Treatment with 100 microM cycloheximide, a protein synthesis inhibitor, replicated the effect of quercetin by inhibiting HIF-1alpha accumulation during hypoxia. These results suggest that suppression of HIF-1alpha accumulation during treatment with quercetin under hypoxic conditions is due to inhibition of protein synthesis. (c) 2008 Wiley-Liss, Inc.

Design, synthesis, and in vitro transfection biology of novel tocopherol based monocationic lipids: a structure-activity investigation.

Science.gov (United States)

Kedika, Bhavani; Patri, Srilakshmi V

2011-01-27

Herein, we report on the design, synthesis, and in vitro gene delivery efficacies of five novel tocopherol based cationic lipids (1-5) in transfecting CHO, B16F10, A-549, and HepG2 cells. The in vitro gene transfer efficiencies of lipids (1-5) were evaluated by both β-galactosidase reporter gene expression and inverted fluorescent microscopic experiments. The results of the present structure-activity investigation convincingly demonstrate that the tocopherol based lipid with three hydroxyl groups in its headgroup region showed 4-fold better transfection efficiency than the commercial formulation. The results also demonstrate that these tocopherol based lipids may be targeted to liver. Transfection efficiency of all the relevant lipids was maintained even when the serum was present during the transfection conditions. The results indicated that the designed systems are quite capable of transferring the DNA into all four types of cells studied with low or no toxicity.

Transfer in SDS of biotinylated proteins from acrylamide gels to an avidin-coated membrane filter.

Science.gov (United States)

Karlin, Arthur; Wang, Chaojian; Li, Jing; Xu, Qiang

2004-06-01

Avidin was covalently linked to aldehyde-derivatized polyethersulfone membrane filters. These filters were used in Western blot analysis of proteins reacted with biotinylation reagents and electrophoresed in sodium dodecyl sulfate (SDS) on polyacrylamide gels. Electrophoretic transfer from the gels to these filters was in 0.1% SDS, in which the covalently bound avidin retained its biotin-binding capacity. We compared Western blots on avidin-coated membrane filters of biotinylated and nonbiotinylated forms of mouse immunoglobulin G (IgG), mouse IgG heavy chain, muscle-type acetylcholine receptor alpha subunit, and fused alpha and beta subunits of receptor. Biotinylated proteins were captured with high specificity compared to their nonbiotinylated counterparts and sensitively detected on the avidin-coated membranes.

Epidural ropivacaine hydrochloride during labour: protein binding, placental transfer and neonatal outcome.

LENUS (Irish Health Repository)

Porter, J M

2012-02-03

This study was undertaken: (i) to quantify the effects of labour and epidural analgesia on plasma alpha1-acid glycoprotein concentration, (ii) to examine the effects of changes in plasma alpha1-acid glycoprotein concentration on plasma protein binding and placental transfer of ropivacaine, and (iii) to examine the association between umbilical venous ropivacaine concentration and neurobehavioural function in the neonate. Multiparous patients undergoing induction of labour received a continuous epidural infusion of 0.1% ropivacaine following an epidural bolus. A significant association was demonstrated between maternal plasma alpha1-acid glycoprotein concentration and 1\\/free fraction of ropivacaine 60 min after starting ropivacaine administration (r(2) = 0.77) but not at delivery. No significant correlation was demonstrable between maternal unbound ropivacaine concentration and either neonatal (cord) ropivacaine concentration or UV\\/MV (a measure of placental transfer). Thirty minutes after delivery, 9\\/10 neonates had neurological and adaptive capacity scores < 35, whereas only three infants had scores < 35 at 2 h. All scores exceeded 35 16 h after delivery. No association between mean (SD) umbilical venous ropivacaine concentration [0.09 (0.08) mg x l(-1)] and neurological and adaptive capacity scores was demonstrated.

Problems with multiple use of transfer buffer in protein electrophoretic transfer.

Science.gov (United States)

Dorri, Yaser; Kurien, Biji T; Scofield, R Hal

2010-04-01

Two-dimensional gel electrophoresis (2DE) and SDS-PAGE are the two most useful methods in protein separation. Proteins separated by 2DE or SDS-PAGE are usually transferred to membranes using a variety of methods, such as electrophoretic transfer, heat-mediated transfer, or nonelectrophoretic transfer, for specific protein detection and/or analysis. In a recent study, Pettegrew et al. claim to reuse transfer buffer containing methanol for at least five times for transferring proteins from SDS-PAGE to polyvinylidene difluoride. They add 150-200 ml fresh transfer solution each time for extended use as a result of loss of transfer buffer. Finally, they test efficiency of each protein transfer by chemiluminescence detection. Here, we comment on this report, as we believe this method is not accurate and useful for protein analysis, and it can cause background binding as well as inaccurate protein analysis.

Design, synthesis, and evaluation of an alpha-helix mimetic library targeting protein-protein interactions.

Science.gov (United States)

Shaginian, Alex; Whitby, Landon R; Hong, Sukwon; Hwang, Inkyu; Farooqi, Bilal; Searcey, Mark; Chen, Jiandong; Vogt, Peter K; Boger, Dale L

2009-04-22

The design and solution-phase synthesis of an alpha-helix mimetic library as an integral component of a small-molecule library targeting protein-protein interactions are described. The iterative design, synthesis, and evaluation of the candidate alpha-helix mimetic was initiated from a precedented triaryl template and refined by screening the designs for inhibition of MDM2/p53 binding. Upon identifying a chemically and biologically satisfactory design and consistent with the screening capabilities of academic collaborators, the corresponding complete library was assembled as 400 mixtures of 20 compounds (20 x 20 x 20-mix), where the added subunits are designed to mimic all possible permutations of the naturally occurring i, i + 4, i + 7 amino acid side chains of an alpha-helix. The library (8000 compounds) was prepared using a solution-phase synthetic protocol enlisting acid/base liquid-liquid extractions for purification on a scale that insures its long-term availability for screening campaigns. Screening of the library for inhibition of MDM2/p53 binding not only identified the lead alpha-helix mimetic upon which the library was based, but also suggests that a digestion of the initial screening results that accompany the use of such a comprehensive library can provide insights into the nature of the interaction (e.g., an alpha-helix mediated protein-protein interaction) and define the key residues and their characteristics responsible for recognition.

Resolution of G(s)alpha and G(q)alpha/G(11)alpha proteins in membrane domains by two-dimensional electrophoresis: the effect of long-term agonist stimulation.

Science.gov (United States)

Matousek, P; Novotný, J; Svoboda, P

2004-01-01

Low-density membrane-domain fractions were prepared from S49 lymphoma cells and clone e2m11 of HEK293 cells expressing a large number of thyrotropin-releasing hormone receptor (TRH-R) and G(11)alpha by flotation on sucrose density gradients. The intact cell structure was broken by detergent-extraction, alkaline-treatment or drastic homogenization. Three types of low-density membranes were resolved by two-dimensional electrophoresis and analyzed for G(s)alpha (S49) or G(q)alpha/G11) (e2m11) content. Four individual immunoblot signals of Gsalpha protein were identified in S49 lymphoma cells indicating complete resolution of the long G(s)alpha L+/-ser and short G(s)alpha S+/-ser variants of G(s)alpha. All these were diminished by prolonged agonist (isoprenaline) stimulation. In e2m11-HEK cells, five different immunoblot signals were detected indicating post-translational modification of G proteins of G(q)alpha/G(11)alpha family. The two major spots corresponding to exogenously (over)expressed G(11)alpha and endogenous G(q)alpha were reduced; the minor spots diminished by hormonal stimulation. Parallel analysis by silver staining of the total protein content indicated that no major changes in protein composition occurred under these conditions. Our data thus indicate that agonist-stimulation of target cells results in down-regulation of all different members of G(s) and G(q)/G(11) families. This agonist-specific effect may be demonstrated in crude membrane as well as domain/raft preparations and it is not accompanied by changes in overall protein composition.

Oxidative stress and acute-phase response in patients with pressure sores.

Science.gov (United States)

Cordeiro, Maria Bernarda Cavalcanti; Antonelli, Elida Juliana; da Cunha, Daniel Ferreira; Júnior, Alceu Afonso Jordão; Júnior, Virmondes Rodrigues; Vannucchi, Helio

2005-09-01

We investigated the relation between oxidative stress and the occurrence of the acute-phase response with serum ascorbic acid and alpha-tocopherol levels in patients with pressure sores. The following groups of patients were studied: 1) those who had patients with pressure sores, 2) those who had pneumonia, and 3) those who did not develop pressure sores or any type of infection (control). Concentrations of total proteins, albumin, creatinine, iron, ferritin, transferrin, C-reactive protein, alpha1-acid glycoprotein, total iron-binding capacity, ascorbic acid, alpha-tocopherol, and malondialdehyde were measured during the first days of hospitalization. Albumin concentrations were significantly lower (P pressure sores compared with controls. Concentrations of ascorbic acid and alpha-tocopherol were significantly decreased (P pressure sores or infection, whereas malondialdehyde concentrations were significantly increased (P pressure sores and 10 of 12 patients (83.33%) with pneumonia presented serum ascorbic acid concentrations below the reference value (34 to 91 micromol/L). Concentrations of ascorbic acid and alpha-tocopherol versus malondialdehyde were significantly correlated in the three patient groups (r = -0.44, P pressure sores and acute infection present a systemic inflammatory response accompanied by an increase in lipid peroxidation that is associated with decreased serum ascorbic acid and alpha-tocopherol levels, suggesting that these patients may be at risk for important nutritional deficiencies.

Some rape/canola seed oils: fatty acid composition and tocopherols.

Science.gov (United States)

Matthaus, Bertrand; Özcan, Mehmet Musa; Al Juhaimi, Fahad

2016-03-01

Seed samples of some rape and canola cultivars were analysed for oil content, fatty acid and tocopherol profiles. Gas liquid chromotography and high performance liquid chromotography were used for fatty acid and tocopherol analysis, respectively. The oil contents of rape and canola seeds varied between 30.6% and 48.3% of the dry weight (ptocopherols were found in rape and canola oils in various amounts: α-tocopherol, γ-tocopherol, δ-tocopherol, β-tocopherol and α-tocotrienol. The major tocopherol in the seed oils of rape and canola cultivars were α-tocopherol (13.22-40.01%) and γ-tocopherol (33.64-51.53%) accompanied by α-T3 (0.0-1.34%) and δ-tocopherol (0.25-1.86%) (ptocopherol contents differ significantly among the cultivars.

Effect of dietary protein on the excretion of. cap alpha. /sub 2u/, the sex-dependent protein of the adult male rat

Energy Technology Data Exchange (ETDEWEB)

Neuhaus, O W; Flory, W

1975-01-01

Adult male rates were maintained on normal (20 percent casein), protein-free (0 percent casein), high protein (50 percent casein), deficient protein (20 percent zein), and a supplemented, deficient protein (20 percent zein plus L-lysine and L-tryptophan) diets. Rats on a protein-free diet excreted approximately 1 mg ..cap alpha../sub 2u//24 h compared with a normal of 10-15 mg/24 h. Depleted rats placed on the normal diet showed a rapid restoration of the normal ..cap alpha../sub 2u/ excretion as well as total urinary proteins. Accumulation of ..cap alpha../sub 2u/ in the blood serum was measured in nephrectomized rats. Rats on the protein free diet accumulated only 30 percent of the ..cap alpha../sub 2u/ compared to normals. On a 50 precent casein diet, rats excreted 30-50 mg ..cap alpha../sub 2u//24 h. However, the accumulation was normal in the serum of nephrectomized rats. A high protein diet did not stimulate ..cap alpha../sub 2u/ synthesis but probably increased the renal loss of all urinary proteins. The excretion of ..cap alpha../sub 2u/ on a zein diet was reduced to the same degree as with the protein-free diet. Supplementation with lysine and tryptophan restored the capacity to eliminate ..cap alpha../sub 2u/ to near normal levels. Accumulation of ..cap alpha../sub 2u/ in the serum of nephrectomized rats kept on the zein diets showed that the effect was to suppress the synthesis of the ..cap alpha../sub 2u/. Supplementation restored the biosynthesis of ..cap alpha../sub 2u/. It is concluded that the effect of dietary protein on the excretion of urinary proteins in the adult male rat is caused in a large part by an influence on the hepatic biosynthesis of ..cap alpha../sub 2u/. The biosynthesis of this protein, which represents approximately 30 percent of the total urinary proteins, is dependent on an adequate supply of dietary protein.

Modulated phases of phospholipid bilayers induced by tocopherols.

Science.gov (United States)

Kamal, Md Arif; Raghunathan, V A

2012-11-01

The influence of α-, γ- and δ-tocopherols on the structure and phase behavior of dipalmitoyl phosphatidylcholine (DPPC) bilayers has been determined from X-ray diffraction studies on oriented multilayers. In all the three cases the main-transition temperature (T(m)) of DPPC was found to decrease with increasing tocopherol concentration up to around 25 mol%. Beyond this the main transition is suppressed in the case of γ-tocopherol, whereas T(m) becomes insensitive to composition in the other two cases. The pre-transition is found to be suppressed over a narrow tocopherol concentration range between 7.5 and 10 mol% in DPPC-γ-tocopherol and DPPC-δ-tocopherol bilayers, and the ripple phase occurs down to the lowest temperature studied. In all the three cases a modulated phase is observed above a tocopherol concentration of about 10 mol%, which is similar to the P(β) phase reported in DPPC-cholesterol bilayers. This phase is found to occur even in excess water conditions at lower tocopherol concentrations, and consists of bilayers with periodic height modulation. These results indicate the ability of tocopherols to induce local curvature in membranes, which could be important for some of their biological functions. Copyright © 2012 Elsevier B.V. All rights reserved.

Serum α-tocopherol and γ-tocopherol concentrations and prostate cancer risk in the PLCO Screening Trial: a nested case-control study.

Directory of Open Access Journals (Sweden)

Stephanie J Weinstein

Full Text Available BACKGROUND: Vitamin E compounds exhibit prostate cancer preventive properties experimentally, but serologic investigations of tocopherols, and randomized controlled trials of supplementation in particular, have been inconsistent. Many studies suggest protective effects among smokers and for aggressive prostate cancer, however. METHODS: We conducted a nested case-control study of serum α-tocopherol and γ-tocopherol and prostate cancer risk in the Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial, with 680 prostate cancer cases and 824 frequency-matched controls. Multivariate-adjusted, conditional logistic regression models were used to estimate odds ratios (OR and 95% confidence intervals (CIs for tocopherol quintiles. RESULTS: Serum α-tocopherol and γ-tocopherol were inversely correlated (r = -0.24, p<0.0001. Higher serum α-tocopherol was associated with significantly lower prostate cancer risk (OR for the highest vs. lowest quintile = 0.63, 95% CI 0.44-0.92, p-trend 0.05. By contrast, risk was non-significantly elevated among men with higher γ-tocopherol concentrations (OR for the highest vs. lowest quintile = 1.35, 95% CI 0.92-1.97, p-trend 0.41. The inverse association between prostate cancer and α-tocopherol was restricted to current and recently former smokers, but was only slightly stronger for aggressive disease. By contrast, the increased risk for higher γ-tocopherol was more pronounced for less aggressive cancers. CONCLUSIONS: Our findings indicate higher α-tocopherol status is associated with decreased risk of developing prostate cancer, particularly among smokers. Although two recent controlled trials did not substantiate an earlier finding of lower prostate cancer incidence and mortality in response to supplementation with a relatively low dose of α-tocopherol, higher α-tocopherol status may be beneficial with respect to prostate cancer risk among smokers. Determining what stage of prostate cancer

Conjugated linoleic acid influences the metabolism of tocopherol in lactating rats but has little effect on tissue tocopherol concentrations in pups.

Science.gov (United States)

Zeitz, Johanna O; Most, Erika; Eder, Klaus

2016-05-31

Conjugated linoleic acid (CLA) is known to affect the lipid metabolism in growing and lactating animals. However, potential effects on the metabolism of fat-soluble vitamins in lactating animals and co-occurring effects on their offspring are unknown. We aimed to investigate the effects of dietary CLA on concentrations of tocopherol in various tissues of lactating rats and their offspring and expression of genes involved in tocopherol metabolism. Twenty-eight Wistar Han rats were allocated to 2 groups and fed either a control diet (control group) or a diet containing 0.9 % of cis-9, trans-11 and trans-10, cis-12 (1:1) CLA (CLA group) during pregnancy and lactation. Feed intake of dams and body weight of dams and their pups were recorded weekly. Tocopherol concentrations in various body tissues were determined at day 14 of lactation in dams and 1, 7 and 14 days after birth in pups. Expression of selected genes involved in metabolism of tocopherol was determined in dams and pups. The data were statistically analysed by analysis of variance. Feed intake and body weight development of nursing rats and their pups was similar in both groups. In livers of CLA-fed dams, tocopherol concentrations decreased by 24 % but expression of TTPA and CYP3A1, involved in tocopherol transport and metabolism, were not influenced. In the dams' adipose tissue, gene expression of receptors involved in tissue tocopherol uptake, LDLR and SCARB1, but not of LPL, increased by 30 to 50 % and tocopherol concentrations increased by 47 % in CLA-fed compared to control dams. Expression of LPL, LDLR and SCARB1 in mammary gland was not influenced by CLA-feeding. Tocopherol concentrations in the pup's livers and lungs were similar in both groups, but at 14 days of age, adipose tissue tocopherol concentrations, and LDLR and SCARB1 expression, were higher in the CLA-exposed pups. We show that dietary CLA affects tissue concentrations of tocopherol in lactating rats and tocopherol metabolism in

Dietary tocopherols inhibit PhIP-induced prostate carcinogenesis in CYP1A-humanized mice.

Science.gov (United States)

Chen, Jayson X; Li, Guangxun; Wang, Hong; Liu, Anna; Lee, Mao-Jung; Reuhl, Kenneth; Suh, Nanjoo; Bosland, Maarten C; Yang, Chung S

2016-02-01

Tocopherols, the major forms of vitamin E, exist as alpha-tocopherol (α-T), β-T, γ-T and δ-T. The cancer preventive activity of vitamin E is suggested by epidemiological studies, but recent large-scale cancer prevention trials with high dose of α-T yielded disappointing results. Our hypothesis that other forms of tocopherols have higher cancer preventive activities than α-T was tested, herein, in a novel prostate carcinogenesis model induced by 2-amino-1-methyl-6-phenylimidazo [4,5-b] pyridine (PhIP), a dietary carcinogen, in the CYP1A-humanized (hCYP1A) mice. Treatment of hCYP1A mice with PhIP (200 mg/kg b.w., i.g.) induced high percentages of mouse prostatic intraepithelial neoplasia (mPIN), mainly in the dorsolateral glands. Supplementation with a γ-T-rich mixture of tocopherols (γ-TmT, 0.3% in diet) significantly inhibited the development of mPIN lesions and reduced PhIP-induced elevation of 8-oxo-deoxyguanosine, COX-2, nitrotyrosine, Ki-67 and p-AKT, and the loss of PTEN and Nrf2. Further studies with purified δ-T, γ-T or α-T (0.2% in diet) showed that δ-T was more effective than γ-T or α-T in preventing mPIN formations and p-AKT elevation. These results indicate that γ-TmT and δ-T could be effective preventive agents of prostate cancer. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

21 CFR 182.8892 - α-Tocopherol acetate.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 3 2010-04-01 2009-04-01 true α-Tocopherol acetate. 182.8892 Section 182.8892 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD...-Tocopherol acetate. (a) Product. α-Tocopherol acetate. (b) Conditions of use. This substance is generally...

Modulation of phosphorylation of tocopherol and phosphatidylinositol by hTAP1/SEC14L2-mediated lipid exchange

Science.gov (United States)

The vitamin E derivative, alpha-tocopheryl phosphate (aTP), is detectable in cultured cells, plasma and tissues in small amounts, suggesting the existence of enzyme(s) with a-tocopherol (aT) kinase activity. Here, we characterize the production of aTP from aT and [g-32P]-ATP in primary human coronar...

Improvement of heterologous protein production in Aspergillus oryzae by RNA interference with alpha-amylase genes.

Science.gov (United States)

Nemoto, Takashi; Maruyama, Jun-ichi; Kitamoto, Katsuhiko

2009-11-01

Aspergillus oryzae RIB40 has three alpha-amylase genes (amyA, amyB, and amyC), and secretes alpha-amylase abundantly. However, large amounts of endogenous secretory proteins such as alpha-amylase can compete with heterologous protein in the secretory pathway and decrease its production yields. In this study, we examined the effects of suppression of alpha-amylase on heterologous protein production in A. oryzae, using the bovine chymosin (CHY) as a reporter heterologous protein. The three alpha-amylase genes in A. oryzae have nearly identical DNA sequences from those promoters to the coding regions. Hence we performed silencing of alpha-amylase genes by RNA interference (RNAi) in the A. oryzae CHY producing strain. The silenced strains exhibited a reduction in alpha-amylase activity and an increase in CHY production in the culture medium. This result suggests that suppression of alpha-amylase is effective in heterologous protein production in A. oryzae.

21 CFR 582.5892 - a-Tocopherol acetate.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 6 2010-04-01 2010-04-01 false a-Tocopherol acetate. 582.5892 Section 582.5892 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Supplements 1 § 582.5892 a-Tocopherol acetate. (a) Product. a-Tocopherol acetate. (b) Conditions of use. This...

Suppression of alpha-tocopherol ether-linked acetic acid in VEGF-induced angiogenesis and the possible mechanisms in human umbilical vein endothelial cells

International Nuclear Information System (INIS)

Chuang, Cheng-Hung; Liu, Chia-Hua; Lu, Ta-Jung; Hu, Miao-Lin

2014-01-01

Alpha-tocopherol ether-linked acetic acid (α-TEA) has been reported to exhibit both anti-tumor and anti-metastatic activities in cell culture and animal studies. However, it is unclear whether α-TEA possesses anti-angiogenic effects. In this study, we investigated the effect of α-TEA on vascular endothelial growth factor (VEGF)-induced angiogenesis and matrix metalloproteinase (MMP) expression both in vitro and ex vivo. We found that the α-TEA inhibited tube formation, invasion, and migration in human umbilical vein endothelial cells (HUVECs) and that such actions were accompanied by reduced expression of MMP-2. α-TEA also inhibited ex vivo angiogenesis, as indicated by chicken egg chorioallantoic membrane assay. We further showed that α-TEA attenuated protein expression of VEGF receptor-2 (VEGFR-2)-mediated p38 mitogen-activated protein kinase (p38), phosphorylated p38, and focal adhesion kinase (FAK). Moreover, α-TEA (30 μM) significantly up-regulated protein expression of tissue inhibitors of MMP (TIMP)-2 (by 138%) and the metastasis suppressor gene nm23-H1 (by 54%). These results demonstrate that the anti-angiogenic effect of α-TEA both in vitro and ex vivo and its possible mechanistic action appears to involve the inhibition of MMP-2 level through VEGFR-2-mediated FAK and p38 signaling pathways and through up-regulation of TIMP-2 and nm23-H1 expression. - Graphical abstract: Possible mechanisms of α-TEA on inhibited angiogenesis of human umbilical vein endothelial cells. Brief summary In the present study, we have demonstrated that VEGF-mediated angiogenesis is significantly inhibited by α-TEA, and that this effect involves inhibition of MMP-2 level through VEGFR-2-mediated FAK and p38 signaling pathways related to invasion and migration. - Highlights: • The anti-angiogenic effect and the mechanistic action of α-TEA were investigated. • α-TEA significantly inhibited VEGF-mediated angiogenesis both in vitro and ex vivo. • α-TEA down

Suppression of alpha-tocopherol ether-linked acetic acid in VEGF-induced angiogenesis and the possible mechanisms in human umbilical vein endothelial cells

Energy Technology Data Exchange (ETDEWEB)

Chuang, Cheng-Hung, E-mail: chchuang@hk.edu.tw [Department of Nutrition, Master Program of Biomedical Nutrition, Hungkuang University, 1018 Sec. 6 Taiwan Boulevard, Taichung 43302, Taiwan, ROC (China); Liu, Chia-Hua [Department of Food Science and Biotechnology, National Chung-Hsing University, 250 Kuo Kuang Road, Taichung 40227, Taiwan, ROC (China); Lu, Ta-Jung [Department of Chemistry, Institute of Technology and Innovation Management, National Chung-Hsing University, 250 Kuo Kuang Road, Taichung 40227, Taiwan, ROC (China); Hu, Miao-Lin, E-mail: mlhuhu@dragon.nchu.edu.tw [Department of Food Science and Biotechnology, National Chung-Hsing University, 250 Kuo Kuang Road, Taichung 40227, Taiwan, ROC (China)

2014-12-15

Alpha-tocopherol ether-linked acetic acid (α-TEA) has been reported to exhibit both anti-tumor and anti-metastatic activities in cell culture and animal studies. However, it is unclear whether α-TEA possesses anti-angiogenic effects. In this study, we investigated the effect of α-TEA on vascular endothelial growth factor (VEGF)-induced angiogenesis and matrix metalloproteinase (MMP) expression both in vitro and ex vivo. We found that the α-TEA inhibited tube formation, invasion, and migration in human umbilical vein endothelial cells (HUVECs) and that such actions were accompanied by reduced expression of MMP-2. α-TEA also inhibited ex vivo angiogenesis, as indicated by chicken egg chorioallantoic membrane assay. We further showed that α-TEA attenuated protein expression of VEGF receptor-2 (VEGFR-2)-mediated p38 mitogen-activated protein kinase (p38), phosphorylated p38, and focal adhesion kinase (FAK). Moreover, α-TEA (30 μM) significantly up-regulated protein expression of tissue inhibitors of MMP (TIMP)-2 (by 138%) and the metastasis suppressor gene nm23-H1 (by 54%). These results demonstrate that the anti-angiogenic effect of α-TEA both in vitro and ex vivo and its possible mechanistic action appears to involve the inhibition of MMP-2 level through VEGFR-2-mediated FAK and p38 signaling pathways and through up-regulation of TIMP-2 and nm23-H1 expression. - Graphical abstract: Possible mechanisms of α-TEA on inhibited angiogenesis of human umbilical vein endothelial cells. Brief summary In the present study, we have demonstrated that VEGF-mediated angiogenesis is significantly inhibited by α-TEA, and that this effect involves inhibition of MMP-2 level through VEGFR-2-mediated FAK and p38 signaling pathways related to invasion and migration. - Highlights: • The anti-angiogenic effect and the mechanistic action of α-TEA were investigated. • α-TEA significantly inhibited VEGF-mediated angiogenesis both in vitro and ex vivo. • α-TEA down

Influence of soy protein’s structural modifications on their microencapsulation properties: a-tocopherol microparticles preparation

OpenAIRE

Nesterenko, Alla; Alric, Isabelle; Silvestre, Françoise; Durrieu, Vanessa

2012-01-01

Enzymatic and chemical modifications of soy protein isolate (SPI) were studied in order to improve SPI properties for their use as wall material for a-tocopherol microencapsulation by spray-drying. The structural modifications of SPI by enzymatic hydrolysis and/or N-acylation were carried out in aqueous media without any use of organic solvent neither surfactant. Emulsions from aqueous solutions of native or modified SPI and hydrophobic a-tocopherol, were prepared and spray-dri...

FORTRAN data files transference from VAX/VMS to ALPHA/UNIX

International Nuclear Information System (INIS)

Sanchez, E.; Milligen, B.Ph. van

1997-01-01

Several tools have been developed to access the TJ-I and TJ-IU databases, which currently reside in VAX/VMS servers, from the TJ-II Data Acquisition System DEC ALPHA 8400 server. The TJ-I/TJ-IU databases are not homogeneous and contain several types of data files, namely, SADE. CAMAC and FORTRAN un formatted files. The tools presented in this report allow one to transfer CAMAC and those FORTRAN un formatted files defined herein. from a VAX/VMS server, for data manipulation on the ALPHA/Digital UNIX server. (Author) 5 refs

Energy landscape, structure and rate effects on strength properties of alpha-helical proteins

International Nuclear Information System (INIS)

Bertaud, Jeremie; Hester, Joshua; Jimenez, Daniel D; Buehler, Markus J

2010-01-01

The strength of protein domains is crucial to identify the mechanical role of protein domains in biological processes such as mechanotransduction, tissue mechanics and tissue remodeling. Whereas the concept of strength has been widely investigated for engineered materials, the strength of fundamental protein material building blocks and how it depends on structural parameters such as the chemical bonding, the protein filament length and the timescale of observation or deformation velocity remains poorly understood. Here we report a systematic analysis of the influence of key parameters that define the energy landscape of the strength properties of alpha-helical protein domains, including energy barriers, unfolding and refolding distances, the locations of folded and unfolded states, as well as variations of the length and pulling velocity of alpha-helical protein filaments. The analysis is facilitated by the development of a double-well mesoscale potential formulation, utilized here to carry out a systematic numerical analysis of the behavior of alpha-helices. We compare the results against widely used protein strength models based on the Bell model, one of the simplest models used to characterize the strength of protein filaments. We find that, whereas Bell-type models are a reasonable approximation to describe the rupture of alpha-helical protein domains for a certain range of pulling speeds and values of energy barriers, the model ceases to hold for very large energy barriers and for very small pulling speeds, in agreement with earlier findings. We conclude with an application of our mesoscale model to investigate the effect of the length of alpha-helices on their mechanical strength. We find a weakening effect as the length of alpha-helical proteins increases, followed by an asymptotic regime in which the strength remains constant. We compare strand lengths found in biological proteins with the scaling law of strength versus alpha-helix filament length. The

Predictors of Sustained Smoking Cessation: A Prospective Analysis of Chronic Smokers From the Alpha-Tocopherol Beta-Carotene Cancer Prevention Study

Science.gov (United States)

Augustson, Erik M.; Wanke, Kay L.; Rogers, Scott; Bergen, Andrew W.; Chatterjee, Nilanjan; Synder, Kirk; Albanes, Demetrius; Taylor, Phil R.; Caporaso, Neil E.

2008-01-01

Objectives. Because US smoking rates have not declined during the past decade, there is a renewed need to identify factors associated with smoking cessation. Using a nested case–control design, we explored the association between ability to sustain cessation over an extended period and demographic, smoking, medical, and behavioral variables. Methods. We selected a sample of 1379 sustained quitters (abstinent from smoking for at least 40 months) and 1388 relapsers (abstinent for more than 8 months before relapse) from participants in the Alpha-Tocopherol Beta-Carotene Cancer Prevention Study, a nutritional intervention study involving Finnish men aged 50 to 69 years at baseline. Contingency table and multiple regression analyses were used to evaluate potential differences between the 2 groups on baseline variables. Results. Compared with sustained quitters, relapsers were more likely to report symptoms of emotional distress and higher levels of nicotine dependence, to drink more alcohol, and to report more medical conditions. Conclusions. Factors associated with both tobacco use and comorbid conditions impact an individual’s ability to maintain long-term smoking cessation. Understanding the underlying mechanisms of action and potential common pathways among these factors may help to improve smoking cessation therapies. PMID:17600267

[Cloning, mutagenesis and symbiotic phenotype of three lipid transfer protein encoding genes from Mesorhizobium huakuii 7653R].

Science.gov (United States)

Li, Yanan; Zeng, Xiaobo; Zhou, Xuejuan; Li, Youguo

2016-12-04

Lipid transfer protein superfamily is involved in lipid transport and metabolism. This study aimed to construct mutants of three lipid transfer protein encoding genes in Mesorhizobium huakuii 7653R, and to study the phenotypes and function of mutations during symbiosis with Astragalus sinicus. We used bioinformatics to predict structure characteristics and biological functions of lipid transfer proteins, and conducted semi-quantitative and fluorescent quantitative real-time PCR to analyze the expression levels of target genes in free-living and symbiotic conditions. Using pK19mob insertion mutagenesis to construct mutants, we carried out pot plant experiments to observe symbiotic phenotypes. MCHK-5577, MCHK-2172 and MCHK-2779 genes encoding proteins belonged to START/RHO alpha_C/PITP/Bet_v1/CoxG/CalC (SRPBCC) superfamily, involved in lipid transport or metabolism, and were identical to M. loti at 95% level. Gene relative transcription level of the three genes all increased compared to free-living condition. We obtained three mutants. Compared with wild-type 7653R, above-ground biomass of plants and nodulenitrogenase activity induced by the three mutants significantly decreased. Results indicated that lipid transfer protein encoding genes of Mesorhizobium huakuii 7653R may play important roles in symbiotic nitrogen fixation, and the mutations significantly affected the symbiotic phenotypes. The present work provided a basis to study further symbiotic function mechanism associated with lipid transfer proteins from rhizobia.

Putrescine treatment reverses α-tocopherol-induced desynchronization of polyamine and retinoid metabolism during rat liver regeneration

Directory of Open Access Journals (Sweden)

Lourdes Sánchez-Sevilla

2016-10-01

Full Text Available Abstract Background The pre-treatment with α-tocopherol inhibits progression of rat liver proliferation induced by partial hepatectomy (PH, by decreasing and/or desynchronizing cyclin D1 expression and activation into the nucleus, activation and nuclear translocation of STAT-1 and -3 proteins and altering retinoid metabolism. Interactions between retinoic acid and polyamines have been reported in the PH-induced rat liver regeneration. Therefore, we evaluated the effect of low dosage of α-tocopherol on PH-induced changes in polyamine metabolism. Methods This study evaluated the participation of polyamine synthesis and metabolism during α-tocopherol-induced inhibition of rat liver regeneration. In PH-rats (Wistar treated with α-tocopherol and putrescine, parameters indicative of cell proliferation, lipid peroxidation, ornithine decarboxylase expression (ODC, and polyamine levels, were determined. Results Pre-treatment with α-tocopherol to PH-animals exerted an antioxidant effect, shifting earlier the increased ODC activity and expression, temporally affecting polyamine synthesis and ornithine metabolism. Whereas administration of putrescine induced minor changes in PH-rats, the concomitant treatment actually counteracted most of adverse actions exerted by α-tocopherol on the remnant liver, restituting its proliferative potential, without changing its antioxidant effect. Putrescine administration to these rats was also associated with lower ODC expression and activity in the proliferating liver, but the temporally shifting in the amount of liver polyamines induced by α-tocopherol, was also “synchronized” by the putrescine administration. The latter is supported by the fact that a close relationship was observed between fluctuations of polyamines and retinoids. Conclusions Putrescine counteracted most adverse actions exerted by α-tocopherol on rat liver regeneration, restoring liver proliferative potential and restituting the decreased

Antioxidant profiling of native Andean potato tubers (Solanum tuberosum L.) reveals cultivars with high levels of beta-carotene, alpha-tocopherol, chlorogenic acid, and petanin.

Science.gov (United States)

Andre, Christelle M; Oufir, Mouhssin; Guignard, Cédric; Hoffmann, Lucien; Hausman, Jean-François; Evers, Danièle; Larondelle, Yvan

2007-12-26

The antioxidant profile of 23 native Andean potato cultivars has been investigated from a human nutrition perspective. The main carotenoid and tocopherol compounds were studied using high-performance liquid chromatography coupled with a diode array detector (HPLC-DAD) and a fluorescence detector, respectively, whereas polyphenols (including anthocyanins in colored tubers) were identified by means of both HPLC-mass spectrometry and HPLC-DAD. Antioxidant profiling revealed significant genotypic variations as well as cultivars of particular interest from a nutritional point of view. Concentrations of the health-promoting carotenoids, lutein and zeaxanthin, ranged from 1.12 to 17.69 microg g(-1) of dry weight (DW) and from 0 to 17.7 microg g(-1) of DW, with cultivars 704353 and 702472 showing the highest levels in lutein and zeaxanthin, respectively. Whereas beta-carotene is rarely reported in potato tubers, remarkable levels of this dietary provitamin A carotenoid were detected in 16 native varieties, ranging from 0.42 to 2.19 microg g(-1) of DW. The amounts of alpha-tocopherol found in Andean potato tubers, extending from 2.73 to 20.80 microg g(-1) of DW, were clearly above the quantities generally reported for commercial varieties. Chlorogenic acid and its isomers dominated the polyphenolic profile of each cultivar. Dark purple-fleshed tubers from the cultivar 704429 contained exceptionally high levels of total anthocyanins (16.33 mg g(-1) of DW). The main anthocyanin was identified as petanin (petunidin-3-p-coumaroyl-rutinoside-5-glucoside). The results suggest that Andean potato cultivars should be exploited in screening and breeding programs for the development of potato varieties with enhanced health and nutritional benefits.

2-Azido-( sup 32 P)NAD+, a photoactivatable probe for G-protein structure: Evidence for holotransducin oligomers in which the ADP-ribosylated carboxyl terminus of alpha interacts with both alpha and gamma subunits

Energy Technology Data Exchange (ETDEWEB)

Vaillancourt, R.R.; Dhanasekaran, N.; Johnson, G.L.; Ruoho, A.E. (Univ. of Wisconsin Medical School, Madison (USA))

1990-05-01

A radioactive and photoactivatable derivative of NAD+, 2-azido-(adenylate-32P)NAD+, has been synthesized and used with pertussis toxin to ADP-ribosylate Cys347 of the alpha subunit (alpha T) of GT, the retinal guanine nucleotide-binding protein. ADP-ribosylation of alpha T followed by light activation of the azide moiety of 2-azido-(adenylate-32P)ADP-ribose produced four crosslinked species involving the alpha and gamma subunits of the GT heterotrimer: an alpha trimer (alpha-alpha-alpha), and alpha-alpha-gamma crosslink, an alpha dimer (alpha-alpha), and an alpha-gamma crosslink. The alpha trimer, alpha-alpha-gamma complex, alpha dimer, and alpha-gamma complexes were immunoreactive with alpha T antibodies. The alpha-alpha-gamma and the alpha-gamma complexes were immunoreactive with antisera recognizing gamma subunits. No evidence was found for crosslinking of alpha T to beta T subunits. Hydrolysis of the thioglycosidic bond between Cys347 and 2-azido-(adenylate-32P)ADP-ribose using mercuric acetate resulted in the transfer of radiolabel from Cys347 of alpha T in the crosslinked oligomers to alpha monomers, indicative of intermolecular photocrosslinking, and to gamma monomers, indicative of either intermolecular crosslinked complexes (between heterotrimers) or intramolecular crosslinked complexes (within the heterotrimer). These results demonstrate that GT exists as an oligomer and that ADP-ribosylated Cys347, which is four residues from the alpha T-carboxyl terminus, is oriented toward and in close proximity to the gamma subunit.

Tocopherol levels in different mango varieties correlate with MiHPPD expression and its over-expression elevates tocopherols in transgenic Arabidopsis and tomato.

Science.gov (United States)

Singh, Rajesh K; Chaurasia, Akhilesh K; Bari, Rupesh; Sane, Vidhu A

2017-10-01

Mango fruit tocopherol levels vary in different varieties during ripening. This study shows that tocopherol accumulation is highly correlated with its p-hydroxyphenyl pyruvate dioxygenase ( MiHPPD ) gene expression during ripening. MiHPPD transcript is ethylene induced and differentially expressed in four mango varieties used in this study. Higher/lower accumulation of tocopherol (mainly α-tocopherol) was achieved by heterologous expression of MiHPPD in Arabidopsis and tomato. The results suggest that tocopherol accumulation in mango fruit is correlated to MiHPPD gene expression. Over-expression of MiHPPD gene channelizes the flux towards tocophreol biosynthesis and could be used as a potential tool for metabolic engineering.

Disintegration and dimerization of δ-tocopherol under radiation effect

International Nuclear Information System (INIS)

Jasinska-Stepniak, A.; Gogolewski, M.; Zabielski, J.

1996-01-01

The goal of the work was to recognize scala changes of δ-tocopherol in model system (diluted in benzene, ethanol and ''in substantia'') after 2.5, 5, 10 and 20 kGy dose irradiation. δ-tocopherol and its mild oxidation products (dimers) after TLC separation were quantitatively determined with Emmerie-Engel method. Relations dose-effect have been defined and radiation capacity has been calculated. The results show that disintegration of δ-tocopherol diluted in ethanol is about ten times stronger the diluted in benzene. δ-tocopherol in benzene was dimerized. The most stable after irradiation was δ-tocopherol ''in substantia''. (author)

Purification of human alpha uterine protein.

Science.gov (United States)

Sutcliffe, R G; Bolton, A E; Sharp, F; Nicholson, L V; MacKinnon, R

1980-03-01

Human alpha uterine protein (AUP) has been prepared from extracts of decudua by antibody affinity chromatography, DEAE Sepharose chromatography and by filtration through Sephadex G-150. This procedure yielded a protein fraction containing AUP, which was labelled with 125I by chloramine T. When analysed by SDS gel electrophoresis this radioiodinated protein fraction was found to contain predominantly a single species of protein which was precipitated by antibodies against AUP in antibody-antigen crossed electrophoresis. Rabbit anti-AUP precipitated 55-65% of the tracer in a double-antibody system. Sephadex G150 gel filtration of AUP obtained before and after affinity chromatography provided a molecular weight estimate of 50000. Since SDS gel electrophoresis revealed a polypeptide molecular weight of 23000-25000, it is suggested that AUP is a dimer.

Expression of G(alpha)(s) proteins and TSH receptor signalling in hyperfunctioning thyroid nodules with TSH receptor mutations.

Science.gov (United States)

Holzapfel, Hans-Peter; Bergner, Beate; Wonerow, Peter; Paschke, Ralf

2002-07-01

Constitutively activating mutations of the thyrotrophin receptor (TSHR) are the main molecular cause of hyperfunctioning thyroid nodules (HTNs). The G protein coupling is an important and critical step in the TSHR signalling which mainly includes G(alpha)(s), G(alpha)(i) and G(alpha)(q)/11 proteins. We investigated the in vitro consequences of overexpressing G(alpha) proteins on signalling of the wild-type (WT) or mutated TSHR. Moreover, we investigated whether changes in G(alpha) protein expression are pathophysiologically relevant in HTNs or cold thyroid nodules (CTNs). Wild-type TSH receptor and mutated TSH receptors were coexpressed with G(alpha)(s), G(alpha)(i) or G(alpha)(q)/11, and cAMP and inositol phosphate (IP) production was measured after stimulation with TSH. The expression of G(alpha)(s), G(alpha)(i) and G(alpha)(q)/11 proteins was examined by Western blotting in 28 HTNs and 14 CTNs. Coexpression of G(alpha)(s) with the WT TSH receptor in COS 7 cells significantly increased the basal and TSH-stimulated cAMP accumulation while coexpression of the G(alpha)(q) or G(alpha)11 protein significantly increased the production of cAMP and inositol triphosphate (IP(3)). The coexpression of the TSH receptor mutants (I486F, DEL613-621), known to couple constitutively to G(alpha)(s) and G(alpha)(q) with G(alpha)(s) and G(alpha)(q)/11, significantly increased the basal and stimulated cAMP and IP(3) accumulation. Coexpression of the TSH receptor mutant V556F with G(alpha)(s) only increased the basal and stimulated cAMP production while its coexpression with G(alpha)(q)/11 increased the basal and stimulated IP(3) signalling. The expression of G(alpha)(s) protein subunits determined by Western blotting was significantly decreased in 14 HTNs with a constitutively activating TSH receptor mutation in comparison with the corresponding surrounding tissue, while in 14 HTNs without TSH receptor or G(alpha)(s) protein mutation and in 14 CTNs the expression of G(alpha

Tocopherols and tocotrienols in serum and liver of dairy cows receiving conjugated linoleic acids or a control fat supplement during early lactation.

Science.gov (United States)

Sadri, H; Dänicke, S; Meyer, Ulrich; Rehage, J; Frank, J; Sauerwein, H

2015-10-01

The fat-soluble vitamin E comprises the 8 structurally related compounds (congeners) α-, β-, γ-, and δ-tocopherol (with a saturated side chain) and α-, β-, γ-, and δ-tocotrienol (with a 3-fold unsaturated side chain). Little is known regarding the blood and liver concentrations of the 8 vitamin E congeners during the transition from pregnancy to lactation in dairy cows. We thus quantified tocopherols (T) and tocotrienols (T3) in serum and liver and hepatic expression of genes involved in vitamin E metabolism in pluriparous German Holstein cows during late gestation and early lactation and investigated whether dietary supplementation (from d 1 in milk) with conjugated linoleic acids (CLA; 100g/d; each 12% of trans-10,cis-12 and cis-9,trans-11 CLA; n=11) altered these compared with control-fat supplemented cows (CTR; n=10). Blood samples and liver biopsies were collected on d -21, 1, 21, 70, and 105 (liver only) relative to calving. In both groups, the serum concentrations of αT, γT, βT3, and δT3 increased from d -21 to d 21 and remained unchanged between d 21 and 70, but were unaffected by CLA. The concentrations of the different congeners of vitamin E in liver did not differ between the CTR and the CLA groups. In both groups, the concentrations of the vitamin E forms in liver changed during the course of the study. The hepatic mRNA abundance of genes controlling vitamin E status did not differ between groups, but α-tocopherol transfer protein and tocopherol-associated protein mRNA increased with time of lactation in both. In conclusion, the concentrations of vitamin E congeners and the expression of genes related to vitamin E status follow characteristic time-related changes during the transition from late gestation to early lactation but are unaffected by CLA supplementation at the dosage used. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Plasma cholesteryl ester transfer protein mass and phospholipid transfer protein activity are associated with leptin in type 2 diabetes mellitus

NARCIS (Netherlands)

Dullaart, R. P. F.; de Vries, R.; Dallinga-Thie, G. M.; van Tol, A.; Sluiter, W. J.

Adipose tissue contributes to plasma levels of lipid transfer proteins and is also the major source of plasma adipokines. We hypothesized that plasma cholesteryl ester transfer protein (CETP) mass, phospholipid transfer protein (PLTP) activity and cholesteryl ester transfer (CET, a measure of CETP

Dietary administration of δ- and γ-tocopherol inhibits tumorigenesis in the animal model of estrogen receptor-positive, but not HER-2 breast cancer.

Science.gov (United States)

Smolarek, Amanda K; So, Jae Young; Burgess, Brenda; Kong, Ah-Ng Tony; Reuhl, Kenneth; Lin, Yong; Shih, Weichung Joe; Li, Guangxun; Lee, Mao-Jung; Chen, Yu-Kuo; Yang, Chung S; Suh, Nanjoo

2012-11-01

Tocopherol, a member of the vitamin E family, consists of four forms designated as α, β, γ, and δ. Several large cancer prevention studies with α-tocopherol have reported no beneficial results, but recent laboratory studies have suggested that δ- and γ-tocopherol may be more effective. In two different animal models of breast cancer, the chemopreventive activities of individual tocopherols were assessed using diets containing 0.3% of tocopherol (α-, δ-, or γ-) or 0.3% of a γ-tocopherol rich mixture (γ-TmT). Although administration of tocopherols did not prevent human epidermal growth factor receptor 2 (HER2/neu)-driven tumorigenesis, δ- and γ-tocopherols inhibited hormone-dependent mammary tumorigenesis in N-methyl-N-nitrosourea (NMU)-treated female Sprague-Dawley rats. NMU-treated rats showed an average tumor burden of 10.6 ± 0.8 g in the control group at 11 weeks, whereas dietary administration of δ- and γ-tocopherols significantly decreased tumor burden to 7.2 ± 0.8 g (P tocopherol treatment groups by 42% (P tocopherol did not decrease tumor burden or multiplicity. In mammary tumors, the protein levels of proapoptotic markers (BAX, cleaved caspase-9, cleaved caspase-3, cleaved PARP) were increased, whereas antiapoptotic markers (Bcl-2, XIAP) were inhibited by δ-tocopherol, γ-tocopherol, and γ-TmT. Furthermore, markers of cell proliferation (PCNA, PKCα), survival (PPAR-γ, PTEN, phospho-Akt), and cell cycle (p53, p21) were affected by δ- and γ-tocopherols. Both δ- and γ-tocopherols, but not α-tocopherol, seem to be promising agents for the prevention of hormone-dependent breast cancer.

Randomized structured triglycerides increase lymphatic absorption of tocopherol and retinol compared with the equivalent physical mixture in a rat model of fat malabsorption.

Science.gov (United States)

Tso, P; Lee, T; DeMichele, S J

2001-08-01

Previously we demonstrated that the digestion, absorption and lymphatic transport of lipid and key essential fatty acids (EFA) from randomly interesterified fish oil/medium-chain structured triglycerides (STG) were significantly higher than an equivalent physical mixture (PM) in a normal lymph fistula rat model and in a rat model of lipid malabsorption caused by ischemia/reperfusion (I/R) injury. The goals of this study were to further explore the potential absorptive benefits of STG by comparing the intestinal absorption and lymphatic transport of tocopherol and retinol when delivered gastrically with either STG or PM under normal conditions and after I/R injury to the small bowel. Food-deprived male Sprague-Dawley rats were randomly assigned to two treatments (sham controls or I/R). Under halothane anesthesia, the superior mesenteric artery (SMA) was occluded for 20 min and then reperfused in I/R rats. The SMA was isolated but not occluded in control rats. In both groups, the mesenteric lymph duct was cannulated and a gastric tube was inserted. Each treatment group received 1 mL of the fish oil/MCT STG or PM (7 rats/group) along with (14)C-alpha-tocopherol and (3)H-retinol through the gastric tube followed by an infusion of PBS at 3 mL/h for 8 h. Lymph was collected hourly for 8 h. Under steady-state conditions, the amount of (14)C-alpha-tocopherol and (3)H-retinol transported into lymph was significantly higher in the STG-fed rats compared with those fed PM in both control and I/R groups. In addition, control and I/R rats given STG had earlier steady-state outputs of (14)C-alpha-tocopherol and (3)H-retinol and maintained approximately 30% higher outputs in lymph throughout the 8-h lymph collection period compared with rats given the PM. We conclude that STG provides the opportunity to potentiate improved absorption of fat-soluble vitamins under normal and malabsorptive states.

Specific binding of [alpha-32P]GTP to cytosolic and membrane-bound proteins of human platelets correlates with the activation of phospholipase C

International Nuclear Information System (INIS)

Lapetina, E.G.; Reep, B.R.

1987-01-01

We have assessed the binding of [alpha- 32 P]GTP to platelet proteins from cytosolic and membrane fractions. Proteins were separated by NaDodSO 4 /PAGE and electrophoretically transferred to nitrocellulose. Incubation of the nitrocellulose blots with [alpha- 32 P]GTP indicated the presence of specific and distinct GTP-binding proteins in cytosol and membranes. Binding was prevented by 10-100 nM GTP and by 100 nM guanosine 5'-[gamma-thio]triphosphate (GTP[gamma S]) or GDP; binding was unaffected by 1 nM-1 microM ATP. One main GTP-binding protein (29.5 kDa) was detected in the membrane fraction, while three others (29, 27, and 21 kDa) were detected in the soluble fraction. Two cytosolic GTP-binding proteins (29 and 27 kDa) were degraded by trypsin; another cytosolic protein (21 kDa) and the membrane-bound protein (29.5 kDa) were resistant to the action of trypsin. Treatment of intact platelets with trypsin or thrombin, followed by lysis and fractionation, did not affect the binding of [alpha- 32 P]GTP to the membrane-bound protein. GTP[gamma S] still stimulated phospholipase C in permeabilized platelets already preincubated with trypsin. This suggests that trypsin-resistant GTP-binding proteins might regulate phospholipase C stimulated by GTP[gamma S

Bovine serum albumin-catalyzed deprotonation of [1-(13)C]glycolaldehyde: protein reactivity toward deprotonation of the alpha-hydroxy alpha-carbonyl carbon.

Science.gov (United States)

Go, Maybelle K; Malabanan, M Merced; Amyes, Tina L; Richard, John P

2010-09-07

Bovine serum albumin (BSA) in D(2)O at 25 degrees C and pD 7.0 was found to catalyze the deuterium exchange reactions of [1-(13)C]glycolaldehyde ([1-(13)C]GA) to form [1-(13)C,2-(2)H]GA and [1-(13)C,2,2-di-(2)H]GA. The formation of [1-(13)C,2-(2)H]GA and [1-(13)C,2,2-di-(2)H]GA in a total yield of 51 +/- 3% was observed at early reaction times, and at later times, [1-(13)C,2-(2)H]GA was found to undergo BSA-catalyzed conversion to [1-(13)C,2,2-di-(2)H]GA. The overall second-order rate constant for these deuterium exchange reactions [(k(E))(P)] equals 0.25 M(-1) s(-1). By comparison, (k(E))(P) values of 0.04 M(-1) s(-1) [Go, M. K., Amyes, T. L., and Richard, J. P. (2009) Biochemistry 48, 5769-5778] and 0.06 M(-1) s(-1) [Go, M. K., Koudelka, A., Amyes, T. L., and Richard, J. P. (2010) Biochemistry 49, 5377-5389] have been determined for the wild-type- and K12G mutant TIM-catalyzed deuterium exchange reactions of [1-(13)C]GA, respectively, to form [1-(13)C,2,2-di-(2)H]GA. These data show that TIM and BSA exhibit a modest catalytic activity toward deprotonation of the alpha-hydroxy alpha-carbonyl carbon. We suggest that this activity is intrinsic to many globular proteins, and that it must be enhanced to demonstrate meaningful de novo design of protein catalysts of proton transfer at alpha-carbonyl carbon.

Direct effects of ionizing radiation on integral membrane proteins. Noncovalent energy transfer requires specific interpeptide interactions

International Nuclear Information System (INIS)

Jhun, E.; Jhun, B.H.; Jones, L.R.; Jung, C.Y.

1991-01-01

The 12 transmembrane alpha helices (TMHs) of human erythrocyte glucose transporter were individually cut by pepsin digestion as membrane-bound 2.5-3.5-kDa peptide fragments. Radiation-induced chemical degradation of these fragments showed an average target size of 34 kDa. This is 10-12 x larger than the average size of an individual TMH, demonstrating that a significant energy transfer occurs among these TMHs in the absence of covalent linkage. Heating this TMH preparation at 100 degree C for 15 min reduced the target size to 5 kDa or less, suggesting that the noncovalent energy transfer requires specific helix-helix interactions. Purified phospholamban, a small (6-kDa) integral membrane protein containing a single TMH, formed a pentameric assembly in sodium dodecyl sulfate. The chemical degradation target size of this phospholamban pentamer was 5-6 kDa, illustrating that not all integral membrane protein assemblies permit intersubunit energy transfer. These findings together with other published observations suggest strongly that significant noncovalent energy transfer can occur within the tertiary and quaternary structure of membrane proteins and that as yet undefined proper molecular interactions are required for such covalent energy transfer. Our results with pepsin-digested glucose transporter also illustrate the importance of the interhelical interaction as a predominating force in maintaining the tertiary structure of a transmembrane protein

Tocopherols in rose hips (Rosa spp.) during ripening.

Science.gov (United States)

Andersson, Staffan C; Olsson, Marie E; Gustavsson, Karl-Erik; Johansson, Eva; Rumpunen, Kimmo

2012-08-15

Rose hips are used as a food ingredient and in health products. They are rich in various bioactive compounds such as carotenoids and vitamin C, but data on their vitamin E content (tocopherols and tocotrienols) are limited. In this study, four different species of Rosa were analysed for tocopherol and tocotrienol content during ripening in three different years. Only α- and γ-tocopherol were found in the fleshy parts of the rose hips, and the tocopherol content and vitamin E activity varied depending on date of harvesting, species and year. The amount of vitamin E activity differed between species of Rosa and years, whereas the changes during ripening were relatively small. The choice of species must be considered if tocopherol content is to be optimised when rose hips are used as a food ingredient. Copyright © 2012 Society of Chemical Industry.

AlphaSpace: Fragment-Centric Topographical Mapping To Target Protein–Protein Interaction Interfaces

Science.gov (United States)

2016-01-01

Inhibition of protein–protein interactions (PPIs) is emerging as a promising therapeutic strategy despite the difficulty in targeting such interfaces with drug-like small molecules. PPIs generally feature large and flat binding surfaces as compared to typical drug targets. These features pose a challenge for structural characterization of the surface using geometry-based pocket-detection methods. An attractive mapping strategy—that builds on the principles of fragment-based drug discovery (FBDD)—is to detect the fragment-centric modularity at the protein surface and then characterize the large PPI interface as a set of localized, fragment-targetable interaction regions. Here, we introduce AlphaSpace, a computational analysis tool designed for fragment-centric topographical mapping (FCTM) of PPI interfaces. Our approach uses the alpha sphere construct, a geometric feature of a protein’s Voronoi diagram, to map out concave interaction space at the protein surface. We introduce two new features—alpha-atom and alpha-space—and the concept of the alpha-atom/alpha-space pair to rank pockets for fragment-targetability and to facilitate the evaluation of pocket/fragment complementarity. The resulting high-resolution interfacial map of targetable pocket space can be used to guide the rational design and optimization of small molecule or biomimetic PPI inhibitors. PMID:26225450

Comparative Effects of Biodynes, Tocotrienol-Rich Fraction, and Tocopherol in Enhancing Collagen Synthesis and Inhibiting Collagen Degradation in Stress-Induced Premature Senescence Model of Human Diploid Fibroblasts

Science.gov (United States)

Jam, Faidruz Azura; Ismail, Zahariah; Wan Ngah, Wan Zurinah

2013-01-01

Biodynes, tocotrienol-rich fraction (TRF), and tocopherol have shown antiaging properties. However, the combined effects of these compounds on skin aging are yet to be investigated. This study aimed to elucidate the skin aging effects of biodynes, TRF, and tocopherol on stress-induced premature senescence (SIPS) model of human diploid fibroblasts (HDFs) by determining the expression of collagen and MMPs at gene and protein levels. Primary HDFs were treated with biodynes, TRF, and tocopherol prior to hydrogen peroxide (H2O2) exposure. The expression of COL1A1, COL3A1, MMP1, MMP2, MMP3, and MMP9 genes was determined by qRT-PCR. Type I and type III procollagen proteins were measured by Western blotting while the activities of MMPs were quantified by fluorometric Sensolyte MMP Kit. Our results showed that biodynes, TRF, and tocopherol upregulated collagen genes and downregulated MMP genes (P < 0.05). Type I procollagen and type III procollagen protein levels were significantly increased in response to biodynes, TRF, and tocopherol treatment (P < 0.05) with reduction in MMP-1, MMP-2, MMP-3, and MMP-9 activities (P < 0.05). These findings indicated that biodynes, TRF, and tocopherol effectively enhanced collagen synthesis and inhibited collagen degradation and therefore may protect the skin from aging. PMID:24396567

Comparative Effects of Biodynes, Tocotrienol-Rich Fraction, and Tocopherol in Enhancing Collagen Synthesis and Inhibiting Collagen Degradation in Stress-Induced Premature Senescence Model of Human Diploid Fibroblasts

Directory of Open Access Journals (Sweden)

Suzana Makpol

2013-01-01

Full Text Available Biodynes, tocotrienol-rich fraction (TRF, and tocopherol have shown antiaging properties. However, the combined effects of these compounds on skin aging are yet to be investigated. This study aimed to elucidate the skin aging effects of biodynes, TRF, and tocopherol on stress-induced premature senescence (SIPS model of human diploid fibroblasts (HDFs by determining the expression of collagen and MMPs at gene and protein levels. Primary HDFs were treated with biodynes, TRF, and tocopherol prior to hydrogen peroxide (H2O2 exposure. The expression of COL1A1, COL3A1, MMP1, MMP2, MMP3, and MMP9 genes was determined by qRT-PCR. Type I and type III procollagen proteins were measured by Western blotting while the activities of MMPs were quantified by fluorometric Sensolyte MMP Kit. Our results showed that biodynes, TRF, and tocopherol upregulated collagen genes and downregulated MMP genes (P<0.05. Type I procollagen and type III procollagen protein levels were significantly increased in response to biodynes, TRF, and tocopherol treatment (P<0.05 with reduction in MMP-1, MMP-2, MMP-3, and MMP-9 activities (P<0.05. These findings indicated that biodynes, TRF, and tocopherol effectively enhanced collagen synthesis and inhibited collagen degradation and therefore may protect the skin from aging.

Plasma levels of α-tocopherol, -tocopherol and selenium in patients ...

African Journals Online (AJOL)

user

2014-08-09

Aug 9, 2014 ... No correlation between. -tocopherol and selenium in PCa subjects, but weak and positive correlation exists in .... consistently among smokers where free radicals .... European perspective on vitamin E: Current knowledge and ...

Dietary administration of δ- and γ-tocopherol inhibits tumorigenesis in the animal model of estrogen-receptor positive, but not HER-2 breast cancer

Science.gov (United States)

Smolarek, Amanda K.; So, Jae Young; Burgess, Brenda; Kong, Ah-Ng Tony; Reuhl, Kenneth; Lin, Yong; Shih, Weichung Joe; Li, Guangxun; Lee, Mao-Jung; Chen, Yu-Kuo; Yang, Chung S.; Suh, Nanjoo

2012-01-01

Tocopherol, a member of the vitamin E family, consists of four forms designated as α, β, γ, and δ. Several large cancer prevention studies with α-tocopherol have reported no beneficial results, but recent laboratory studies have suggested that δ- and γ-tocopherol may be more effective. In two different animal models of breast cancer, the chemopreventive activities of individual tocopherols were assessed using diets containing 0.3% of tocopherol (α-, δ- or γ-) or 0.3% of a γ-tocopherol rich mixture (γ-TmT). While administration of tocopherols did not prevent human epidermal growth factor receptor 2 (HER2/neu)-driven tumorigenesis, δ- and γ-tocopherols inhibited hormone-dependent mammary tumorigenesis in N-methyl-N-nitrosourea (NMU)-treated female Sprague Dawley rats. NMU-treated rats showed an average tumor burden of 10.6 ± 0.8 g in the control group at 11 weeks, whereas dietary administration of δ- and γ-tocopherols significantly decreased tumor burden to 7.2 ± 0.8 g (ptocopherol treatment groups by 42% (ptocopherol did not decrease tumor burden or multiplicity. In mammary tumors, the protein levels of pro-apoptotic markers (BAX, cleaved-caspase 9, cleaved-caspase 3, cleaved-PARP) were increased, while anti-apoptotic markers (Bcl2, XIAP) were inhibited by δ-tocopherol, γ-tocopherol and γ-TmT. Furthermore, markers of cell proliferation (PCNA, PKC α), survival (PPARγ, PTEN, phospho-Akt) and cell cycle (p53, p21) were affected by δ- and γ-tocopherols. Both δ- and γ-tocopherols, but not α-tocopherol, appear to be promising agents for the prevention of hormone-dependent breast cancer. PMID:22964476

Genetic Analysis of Reduced γ-Tocopherol Content in Ethiopian Mustard Seeds.

Science.gov (United States)

García-Navarro, Elena; Fernández-Martínez, José M; Pérez-Vich, Begoña; Velasco, Leonardo

2016-01-01

Ethiopian mustard (Brassica carinata A. Braun) line BCT-6, with reduced γ-tocopherol content in the seeds, has been previously developed. The objective of this research was to conduct a genetic analysis of seed tocopherols in this line. BCT-6 was crossed with the conventional line C-101 and the F1, F2, and BC plant generations were analyzed. Generation mean analysis using individual scaling tests indicated that reduced γ-tocopherol content fitted an additive-dominant genetic model with predominance of additive effects and absence of epistatic interactions. This was confirmed through a joint scaling test and additional testing of the goodness of fit of the model. Conversely, epistatic interactions were identified for total tocopherol content. Estimation of the minimum number of genes suggested that both γ- and total tocopherol content may be controlled by two genes. A positive correlation between total tocopherol content and the proportion of γ-tocopherol was identified in the F2 generation. Additional research on the feasibility of developing germplasm with high tocopherol content and reduced concentration of γ-tocopherol is required.

Genetic Analysis of Reduced γ-Tocopherol Content in Ethiopian Mustard Seeds

Directory of Open Access Journals (Sweden)

Elena García-Navarro

2016-01-01

Full Text Available Ethiopian mustard (Brassica carinata A. Braun line BCT-6, with reduced γ-tocopherol content in the seeds, has been previously developed. The objective of this research was to conduct a genetic analysis of seed tocopherols in this line. BCT-6 was crossed with the conventional line C-101 and the F1, F2, and BC plant generations were analyzed. Generation mean analysis using individual scaling tests indicated that reduced γ-tocopherol content fitted an additive-dominant genetic model with predominance of additive effects and absence of epistatic interactions. This was confirmed through a joint scaling test and additional testing of the goodness of fit of the model. Conversely, epistatic interactions were identified for total tocopherol content. Estimation of the minimum number of genes suggested that both γ- and total tocopherol content may be controlled by two genes. A positive correlation between total tocopherol content and the proportion of γ-tocopherol was identified in the F2 generation. Additional research on the feasibility of developing germplasm with high tocopherol content and reduced concentration of γ-tocopherol is required.

A novel eye drop of alpha tocopherol to prevent ocular oxidant damage: improve the stability and ocular efficacy.

Science.gov (United States)

Xin, Jiayu; Tang, Jingling; Bu, Meng; Sun, Yanhui; Wang, Xinyu; Wu, Linhua; Liu, Hongzhuo

2016-01-01

The aim of this study was to design novel mixed micelles as an ophthalmic delivery system for alpha-tocopherol (TOC) to prevent its degradation and improve ocular efficacy. The nonionic polymers, Polyoxyl 15 Hydroxystearate (Solutol® HS15) and Pluronic® F127, were discovered to be the most effective agents for retaining the activity and solubilization of TOC, respectively. Prepared by a thin-film hydration method, HS15/Pluronic® F127 yielded good encapsulation percentages of TOC, with a 27.7% drug loading efficiency. Incorporation of cetalkonium chloride (CKC) into HS15/Pluronic® F127 mixed micelles made the zeta potential of the micelles +17 mV, potentially prolonging the residence time of formulations on ocular surfaces. The optimized micelle preparation remained stable when diluted in a synthetic tear solution. It is known that the antioxidant ability of TOC in typical formulations reduces to around 85% of its initial value after 1 month when stored at 4 or 25 °C under an air atmosphere, which limits ophthalmic applications to less than 1 month. However, encapsulated TOC in investigated micelles remained stable for at least 6 months when sealed with N2. Finally, the cationic micelles were well tolerated after multiple administrations in rabbits, and they improved ocular accumulation of TOC. Taken together, these data suggest that the optimized micelle preparations described in this study may be suitable drug carriers for the treatment of ocular oxidant damage.

Tocopherols and tocotrienols plasma levels are associated with cognitive impairment.

Science.gov (United States)

Mangialasche, Francesca; Xu, Weili; Kivipelto, Miia; Costanzi, Emanuela; Ercolani, Sara; Pigliautile, Martina; Cecchetti, Roberta; Baglioni, Mauro; Simmons, Andrew; Soininen, Hilkka; Tsolaki, Magda; Kloszewska, Iwona; Vellas, Bruno; Lovestone, Simon; Mecocci, Patrizia

2012-10-01

Vitamin E includes 8 natural compounds (4 tocopherols, 4 tocotrienols) with potential neuroprotective activity. α-Tocopherol has mainly been investigated in relation to cognitive impairment. We examined the relation of all plasma vitamin E forms and markers of vitamin E damage (α-tocopherylquinone, 5-nitro-γ-tocopherol) to mild cognitive impairment (MCI) and Alzheimer's disease (AD). Within the AddNeuroMed-Project, plasma tocopherols, tocotrienols, α-tocopherylquinone, and 5-nitro-γ-tocopherol were assessed in 168 AD cases, 166 MCI, and 187 cognitively normal (CN) people. Compared with cognitively normal subjects, AD and MCI had lower levels of total tocopherols, total tocotrienols, and total vitamin E. In multivariable-polytomous-logistic regression analysis, both MCI and AD cases had 85% lower odds to be in the highest tertile of total tocopherols and total vitamin E, and they were, respectively, 92% and 94% less likely to be in the highest tertile of total tocotrienols than the lowest tertile. Further, both disorders were associated with increased vitamin E damage. Low plasma tocopherols and tocotrienols levels are associated with increased odds of MCI and AD. Copyright © 2012 Elsevier Inc. All rights reserved.

Probing the dynamic interface between trimethylamine dehydrogenase (TMADH) and electron transferring flavoprotein (ETF) in the TMADH-2ETF complex: role of the Arg-alpha237 (ETF) and Tyr-442 (TMADH) residue pair.

Science.gov (United States)

Burgess, Selena G; Messiha, Hanan Latif; Katona, Gergely; Rigby, Stephen E J; Leys, David; Scrutton, Nigel S

2008-05-06

We have used multiple solution state techniques and crystallographic analysis to investigate the importance of a putative transient interaction formed between Arg-alpha237 in electron transferring flavoprotein (ETF) and Tyr-442 in trimethylamine dehydrogenase (TMADH) in complex assembly, electron transfer, and structural imprinting of ETF by TMADH. We have isolated four mutant forms of ETF altered in the identity of the residue at position 237 (alphaR237A, alphaR237K, alphaR237C, and alphaR237E) and with each form studied electron transfer from TMADH to ETF, investigated the reduction potentials of the bound ETF cofactor, and analyzed complex formation. We show that mutation of Arg-alpha237 substantially destabilizes the semiquinone couple of the bound FAD and impedes electron transfer from TMADH to ETF. Crystallographic structures of the mutant ETF proteins indicate that mutation does not perturb the overall structure of ETF, but leads to disruption of an electrostatic network at an ETF domain boundary that likely affects the dynamic properties of ETF in the crystal and in solution. We show that Arg-alpha237 is required for TMADH to structurally imprint the as-purified semiquinone form of wild-type ETF and that the ability of TMADH to facilitate this structural reorganization is lost following (i) redox cycling of ETF, or simple conversion to the oxidized form, and (ii) mutagenesis of Arg-alpha237. We discuss this result in light of recent apparent conflict in the literature relating to the structural imprinting of wild-type ETF. Our studies support a mechanism of electron transfer by conformational sampling as advanced from our previous analysis of the crystal structure of the TMADH-2ETF complex [Leys, D. , Basran, J. , Sutcliffe, M. J., and Scrutton, N. S. (2003) Nature Struct. Biol. 10, 219-225] and point to a key role for the Tyr-442 (TMADH) and Arg-alpha237 (ETF) residue pair in transiently stabilizing productive electron transfer configurations. Our work

Transcriptional activation of the mouse obese (ob) gene by CCAAT/enhancer binding protein alpha

DEFF Research Database (Denmark)

Hwang, C S; Mandrup, S; MacDougald, O A

1996-01-01

Like other adipocyte genes that are transcriptionally activated by CCAAT/enhancer binding protein alpha (C/EBP alpha) during preadipocyte differentiation, expression of the mouse obese (ob) gene is immediately preceded by the expression of C/EBP alpha. While the 5' flanking region of the mouse ob...... gene contains several consensus C/EBP binding sites, only one of these sites appears to be functional. DNase I cleavage inhibition patterns (footprinting) of the ob gene promoter revealed that recombinant C/EBP alpha, as well as a nuclear factor present in fully differentiated 3T3-L1 adipocytes...... to a consensus C/EBP binding site at nucleotides -55 to -47 generated a specific protein-oligonucleotide complex that was supershifted by antibody against C/EBP alpha. Probes corresponding to two upstream consensus C/EBP binding sites failed to generate protein-oligonucleotide complexes. Cotransfection of a C...

Irradiation Effect on Oxidative Condition and Tocopherol Content of Vegetable Oils

Directory of Open Access Journals (Sweden)

Konstantinos Sflomos

2007-06-01

Full Text Available The effect on induction period and tocopherol content after γ-irradiation onsamples of olive oil and seed oils (sunflower and soybean was determined. In seed oilsamples 0, 100, 200 and 300 ppm of δ-tocopherol were added before irradiation with 1, 2and 3kGy. The results of induction period showed that, after irradiation, all samplespresented a significant decreased in resistance to oxidation. However, this decrease wasminimized when δ-tocopherol was added. Irradiation significantly decreased the level oftocopherols. δ-Tocopherol appeared more sensitive in irradiation process than α- andγ-tocopherol. The addition of δ-tocopherol significantly reduced, in most cases, thedepletion of the other tocopherols.

Structure and function of small heat shock/alpha-crystallin proteins: established concepts and emerging ideas.

Science.gov (United States)

MacRae, T H

2000-06-01

Small heat shock/alpha-crystallin proteins are defined by conserved sequence of approximately 90 amino acid residues, termed the alpha-crystallin domain, which is bounded by variable amino- and carboxy-terminal extensions. These proteins form oligomers, most of uncertain quaternary structure, and oligomerization is prerequisite to their function as molecular chaperones. Sequence modelling and physical analyses show that the secondary structure of small heat shock/alpha-crystallin proteins is predominately beta-pleated sheet. Crystallography, site-directed spin-labelling and yeast two-hybrid selection demonstrate regions of secondary structure within the alpha-crystallin domain that interact during oligomer assembly, a process also dependent on the amino terminus. Oligomers are dynamic, exhibiting subunit exchange and organizational plasticity, perhaps leading to functional diversity. Exposure of hydrophobic residues by structural modification facilitates chaperoning where denaturing proteins in the molten globule state associate with oligomers. The flexible carboxy-terminal extension contributes to chaperone activity by enhancing the solubility of small heat shock/alpha-crystallin proteins. Site-directed mutagenesis has yielded proteins where the effect of the change on structure and function depends upon the residue modified, the organism under study and the analytical techniques used. Most revealing, substitution of a conserved arginine residue within the alpha-crystallin domain has a major impact on quaternary structure and chaperone action probably through realignment of beta-sheets. These mutations are linked to inherited diseases. Oligomer size is regulated by a stress-responsive cascade including MAPKAP kinase 2/3 and p38. Phosphorylation of small heat shock/alpha-crystallin proteins has important consequences within stressed cells, especially for microfilaments.

Effects of oral micellized natural vitamin E (D-α-tocopherol) v. syntheric vitamin E (DL-α-tocopherol) in feed on α-tocopherol levels, stereoisomer distribution, oxidative stress and the immune response in piglets

DEFF Research Database (Denmark)

Amazan, D; Cordero, G; López-Bote, C J

2014-01-01

This study evaluated the strategy of supplementing oral micellized natural vitamin E (d-α-tocopherol) to either piglets and/or sows on α-tocopherol concentrations in piglets serum and tissues after weaning. One first experiment tested the influence of the vitamin E supplementation source (natural...... supplementation on some of these parameters in piglets. Oral supplementation to sows with natural vitamin E as a micellized form (d-α-tocopherol) at the lowest dose produced a similar concentration of α-tocopherol in serum at days 2, 14 and 28 postpartum to those supplemented with threefold higher dose.......001) and lower (Pimportance of sow over piglet vitamin E supplementation was observed on stereoisomer distribution in piglets. Low doses of oral natural vitamin E supplementation...

Alpha-crystallin-type heat shock proteins: socializing minichaperones in the context of a multichaperone network.

Science.gov (United States)

Narberhaus, Franz

2002-03-01

Alpha-crystallins were originally recognized as proteins contributing to the transparency of the mammalian eye lens. Subsequently, they have been found in many, but not all, members of the Archaea, Bacteria, and Eucarya. Most members of the diverse alpha-crystallin family have four common structural and functional features: (i) a small monomeric molecular mass between 12 and 43 kDa; (ii) the formation of large oligomeric complexes; (iii) the presence of a moderately conserved central region, the so-called alpha-crystallin domain; and (iv) molecular chaperone activity. Since alpha-crystallins are induced by a temperature upshift in many organisms, they are often referred to as small heat shock proteins (sHsps) or, more accurately, alpha-Hsps. Alpha-crystallins are integrated into a highly flexible and synergistic multichaperone network evolved to secure protein quality control in the cell. Their chaperone activity is limited to the binding of unfolding intermediates in order to protect them from irreversible aggregation. Productive release and refolding of captured proteins into the native state requires close cooperation with other cellular chaperones. In addition, alpha-Hsps seem to play an important role in membrane stabilization. The review compiles information on the abundance, sequence conservation, regulation, structure, and function of alpha-Hsps with an emphasis on the microbial members of this chaperone family.

Determination by transfer reaction of alpha widths in fluorine for astrophysical interest

International Nuclear Information System (INIS)

Oliveira Santos, F. de

1995-04-01

The nucleosynthesis of fluorine is not known. Several astrophysical models predict the alpha radiative capture onto N 15 as the main fluorine production reaction. In the expression of the reaction rate, one parameter is missing: the alpha width of the resonance on the E = 4.377 MeV level in fluorine. A direct measurement is excluded due to the very low cross-section expected. We have determined this alpha width using a transfer reaction followed by analyses with FR-DWBA (Finite Range Distorted Wave Born Approximation) in a simple cluster alpha model. This experiment was carried out with a Li 7 beam with E = 28 MeV onto a N 15 gas target. The 16 first levels were studied. Spectroscopic factors were extracted for most of them. Alpha widths for unbound levels were determined. Many alpha width were compared with known values from direct reaction and the differences lie within the uncertainty range (factor 2). The alpha width for the E = 4.377 MeV level was determined (Γ α = 1.5*10 -15 MeV), its value is about 60 times weaker than the used value. The influence of our new rate was studied in AGB (Asymptotic Giant Branch) stars during thermal pulses. In this model the alteration is sensitive. (author)

Fluorescent Protein Approaches in Alpha Herpesvirus Research

Directory of Open Access Journals (Sweden)

Ian B. Hogue

2015-11-01

Full Text Available In the nearly two decades since the popularization of green fluorescent protein (GFP, fluorescent protein-based methodologies have revolutionized molecular and cell biology, allowing us to literally see biological processes as never before. Naturally, this revolution has extended to virology in general, and to the study of alpha herpesviruses in particular. In this review, we provide a compendium of reported fluorescent protein fusions to herpes simplex virus 1 (HSV-1 and pseudorabies virus (PRV structural proteins, discuss the underappreciated challenges of fluorescent protein-based approaches in the context of a replicating virus, and describe general strategies and best practices for creating new fluorescent fusions. We compare fluorescent protein methods to alternative approaches, and review two instructive examples of the caveats associated with fluorescent protein fusions, including describing several improved fluorescent capsid fusions in PRV. Finally, we present our future perspectives on the types of powerful experiments these tools now offer.

Cluster protein structures using recurrence quantification analysis on coordinates of alpha-carbon atoms of proteins

International Nuclear Information System (INIS)

Zhou Yu; Yu Zuguo; Anh, Vo

2007-01-01

The 3-dimensional coordinates of alpha-carbon atoms of proteins are used to distinguish the protein structural classes based on recurrence quantification analysis (RQA). We consider two independent variables from RQA of coordinates of alpha-carbon atoms, %determ1 and %determ2, which were defined by Webber et al. [C.L. Webber Jr., A. Giuliani, J.P. Zbilut, A. Colosimo, Proteins Struct. Funct. Genet. 44 (2001) 292]. The variable %determ2 is used to define two new variables, %determ2 1 and %determ2 2 . Then three variables %determ1, %determ2 1 and %determ2 2 are used to construct a 3-dimensional variable space. Each protein is represented by a point in this variable space. The points corresponding to proteins from the α, β, α+β and α/β structural classes position into different areas in this variable space. In order to give a quantitative assessment of our clustering on the selected proteins, Fisher's discriminant algorithm is used. Numerical results indicate that the discriminant accuracies are very high and satisfactory

Tocopherol in irradiation of temporary hypoxic tumours

International Nuclear Information System (INIS)

Kaagerud, A.; Lund, N.; Peterson, H.I.

1981-01-01

The influence of tocopherol on the effect of local irradiation under induced ischaemia by temporary tourniquet of two rat tumours transplanted intramuscularly into one hindleg was evaluated. An impaired retardation of growth rate occurred in tumours irradiated under ischaemia. This effect was eliminated by pretreatment of animals with tocopherol. In separate experiments the method of inducing ischaemia was investigated by MDO-electrode measurements of tumour tissue oxygen pressure. A significant tumour hypoxia was found under tourniquet of the tumour-bearing leg of the animals. Pretreatment with tocopherol did not influence the tumour pO 2 . (Auth.)

Physico-chemical properties, fatty acid and tocopherol composition of oils from some Sudanese oil bearing sources

Directory of Open Access Journals (Sweden)

Matthäus, Bertrand

2008-12-01

Full Text Available Seven oils, obtained from seven Sudanese oil bearing sources that are Albizia lebbek Oil (ALO, Cassia obtusifolia Oil (COO, Cassia occidentalis Oil (CCO, Abutilon pannosum Oil (APO, Mitracarpus villous Oil (MVO, Ipomea indica Oil (IIO and Sesamum alatum Oil (SAO, were investigated. The seeds were collected in Sudan from Ghibaish, North Kordofan state. In addition to the oil content, the fatty acid was determined by capillary gas chromatography and the tocopherols were evaluated by highperformance liquid chromatography. The oil content of the seven seeds amounted to 12.8, 7.0, 3.2, 7.1, 11.5, 8.8, and 21.3%, respectively.The oils contained 16.4, 20.0, 14.3, 16.8, 19.4, 19.9 and 10.9 % palmitic acid and 21.0, 24.4, 22.1, 10.9, 27.7, 34.0, 45.1 % oleic acid, and 43.8, 38.2, 45.0, 63.9, 34.6, 33.5, 36.3 % linoleic acid and traces of linolenic acid, respectively.The tocopherol content of these oils amounted to 85.6, 48.2, 32.7, 163.5, 52.5, 30.9, and 26.4 mg/100 g oil, respectively. Alpha-tocopherol was the predominant tocopherol in the oil of Albizia lebbek, Cassia obtusifolia, Cassia occidentalis, and Abutilon pannosum, while gamma-tocopherol was the predominant tocopherol in the oil of Mitracarpus villous, Ipomea indica and Sesamum alatum.Se analizan siete aceites procedentes de plantas y semillas de Sudán: Albizia lebbek Oil (ALO, Cassia obtusifolia Oil (COO, Cassia occidentalis Oil (CCO, Abutilon pannosum Oil (APO, Mitracarpus villous Oil (MVO, Ipomea indica Oil (IIO y Sesamum alatum Oil (SAO. Las semillas se recolectaron en el estado de Ghibaish, North Kordofan. Además del contenido en aceite (12.8, 7.0, 3.2, 7.1, 11.5, 8.8, y 21.3 %, respectivamente, se determinaron los ácidos grasos mediante cromatografía de gases y los tocoferoles mediante HPLC. Los aceites contenían, respectivamente, 16.4, 20.0, 14.3, 16.8, 19.4, 19.9 y 10.9 % de ácido palmitito, 21.0, 24.4, 22.1, 10.9, 27.7, 34.0, 45.1 % de ácido oleico, 43.8, 38.2, 45.0, 63.9, 34

Wheat IgE-mediated food allergy in European patients: alpha-amylase inhibitors, lipid transfer proteins and low-molecular-weight glutenins

DEFF Research Database (Denmark)

Pastorello, Elide A; Farioli, Laura; Conti, Amedeo

2007-01-01

for sodium dodecyl sulfate-polyacrylamide gel electrophoresis/immunoblotting of the three Osborne's protein fractions (albumin/globulin, gliadins and glutenins) of raw and cooked wheat. Thermal sensitivity of wheat lipid transfer protein (LTP) was investigated by spectroscopic approaches. IgE cross...

Tocopherol synthesis from homogentisate in Capsicum anuum L. (yellow pepper) chromoplast membranes: evidence for tocopherol cyclase.

OpenAIRE

Arango, Y; Heise, K P

1998-01-01

The present study shows for the first time appreciable tocopherol cyclase activities in plastidial membrane preparations of Capsicum annuum L. (yellow pepper) fruits. When chromoplast membranes from yellow peppers were incubated with [3H]homogentisate and phytyl pyrophosphate under strictly reducing conditions, all biosynthesis precursors were labelled. The main labelling was found in gamma-tocopherol. These observations contradict the hypothesis that assigns a rate-limiting function to tocop...

Specific interaction of capsid protein and importin-{alpha}/{beta} influences West Nile virus production

Energy Technology Data Exchange (ETDEWEB)

Bhuvanakantham, Raghavan; Chong, Mun-Keat [Flavivirology Laboratory, Department of Microbiology, 5 Science Drive 2, National University of Singapore, Singapore 117597 (Singapore); Ng, Mah-Lee, E-mail: micngml@nus.edu.sg [Flavivirology Laboratory, Department of Microbiology, 5 Science Drive 2, National University of Singapore, Singapore 117597 (Singapore)

2009-11-06

West Nile virus (WNV) capsid (C) protein has been shown to enter the nucleus of infected cells. However, the mechanism by which C protein enters the nucleus is unknown. In this study, we have unveiled for the first time that nuclear transport of WNV and Dengue virus C protein is mediated by their direct association with importin-{alpha}. This interplay is mediated by the consensus sequences of bipartite nuclear localization signal located between amino acid residues 85-101 together with amino acid residues 42 and 43 of C protein. Elucidation of biological significance of importin-{alpha}/C protein interaction demonstrated that the binding efficiency of this association influenced the nuclear entry of C protein and virus production. Collectively, this study illustrated the molecular mechanism by which the C protein of arthropod-borne flavivirus enters the nucleus and showed the importance of importin-{alpha}/C protein interaction in the context of flavivirus life-cycle.

RRR-alpha-tocopheryl succinate inhibits EL4 thymic lymphoma cell growth by inducing apoptosis and DNA synthesis arrest.

Science.gov (United States)

Yu, W; Sanders, B G; Kline, K

1997-01-01

RRR-alpha-tocopheryl succinate (vitamin E succinate, VES) treatment of murine EL4 T lymphoma cells induced the cells to undergo apoptosis. After 48 hours of VES treatment at 20 micrograms/ml, 95% of cells were apoptotic. Evidence for the induction of apoptosis by VES treatments is based on staining of DNA for detection of chromatin condensation/fragmentation, two-color flow-cytometric analyses of DNA content, and end-labeled DNA and electrophoretic analyses for detection of DNA ladder formation. VES-treated EL4 cells were blocked in the G1 cell cycle phase; however, apoptotic cells came from all cell cycle phases. Analyses of mRNA expression of genes involved in apoptosis revealed decreased c-myc and increased bcl-2, c-fos, and c-jun mRNAs within three to six hours after treatment. Western analyses showed increased c-Jun, c-Fos, and Bcl-2 protein levels. Electrophoretic mobility shift assays showed increased AP-1 binding at 6, 12, and 24 hours after treatment and decreased c-Myc binding after 12 and 24 hours of VES treatment. Treatments of EL4 cells with VES+RRR-alpha-to-copherol reduced apoptosis without effecting DNA synthesis arrest. Treatments of EL4 cells with VES+rac-6-hydroxyl-2, 5,7,8-tetramethyl-chroman-2-carboxylic acid, butylated hydroxytoluene, or butylated hydroxyanisole had no effect on apoptosis or DNA synthesis arrest caused by VES treatments. Analyses of bcl-2, c-myc, c-jun, and c-fos mRNA levels in cells receiving VES + RRR-alpha-tocopherol treatments showed no change from cells receiving VES treatments alone, implying that these changes are correlated with VES treatments but are not causal for apoptosis. However, treatments with VES + RRR-alpha-tocopherol decreased AP-1 binding to consensus DNA oligomer, suggesting AP-1 involvement in apoptosis induced by VES treatments.

Effects of dietary alpha-tocopherol and beta-carotene on lipid peroxidation induced by methyl mercuric chloride in mice

DEFF Research Database (Denmark)

Andersen, H R; Andersen, O

1993-01-01

-Tocopherol did not protect against CH3HgCl induced lipid peroxidation in the brain. Excess dietary beta-carotene further enhanced CH3HgCl induced lipid peroxidation in liver, kidney and brain. CH3HgCl significantly decreased the activity of total glutathione peroxidase (T-GSH-Px) and Se-dependent glutathione...

Comparative Analysis of Tocopherol Biosynthesis Genes and Its Transcriptional Regulation in Soybean Seeds.

Science.gov (United States)

T, Vinutha; Bansal, Navita; Kumari, Khushboo; Prashat G, Rama; Sreevathsa, Rohini; Krishnan, Veda; Kumari, Sweta; Dahuja, Anil; Lal, S K; Sachdev, Archana; Praveen, Shelly

2017-12-20

Tocopherols composed of four isoforms (α, β, γ, and δ) and its biosynthesis comprises of three pathways: methylerythritol 4-phosphate (MEP), shikimate (SK) and tocopherol-core pathways regulated by 25 enzymes. To understand pathway regulatory mechanism at transcriptional level, gene expression profile of tocopherol-biosynthesis genes in two soybean genotypes was carried out, the results showed significantly differential expression of 5 genes: 1-deoxy-d-xylulose-5-P-reductoisomerase (DXR), geranyl geranyl reductase (GGDR) from MEP, arogenate dehydrogenase (TyrA), tyrosine aminotransferase (TAT) from SK and γ-tocopherol methyl transferase 3 (γ-TMT3) from tocopherol-core pathways. Expression data were further analyzed for total tocopherol (T-toc) and α-tocopherol (α-toc) content by coregulation network and gene clustering approaches, the results showed least and strong association of γ-TMT3/tocopherol cyclase (TC) and DXR/DXS, respectively, with gene clusters of tocopherol biosynthesis suggested the specific role of γ-TMT3/TC in determining tocopherol accumulation and intricacy of DXR/DXS genes in coordinating precursor pathways toward tocopherol biosynthesis in soybean seeds. Thus, the present study provides insight into the major role of these genes regulating the tocopherol synthesis in soybean seeds.

Bacterial expression and one-step purification of an isotope-labeled heterotrimeric G-protein {alpha}-subunit

Energy Technology Data Exchange (ETDEWEB)

Abdulaev, Najmoutin G. [University of Maryland Biotechnology Institute, Center for Advanced Research in Biotechnology (United States); Zhang Cheng; Dinh, Andy [University of Texas Health Science Center, Center for Membrane Biology, Department of Biochemistry and Molecular Biology (United States); Ngo, Tony; Bryan, Philip N. [University of Maryland Biotechnology Institute, Center for Advanced Research in Biotechnology (United States); Brabazon, Danielle M. [Loyola College in Maryland, Department of Chemistry (United States); Marino, John P. [University of Maryland Biotechnology Institute, Center for Advanced Research in Biotechnology (United States)], E-mail: marino@carb.nist.gov; Ridge, Kevin D. [University of Texas Health Science Center, Center for Membrane Biology, Department of Biochemistry and Molecular Biology (United States)

2005-05-15

Heterologous expression systems are often employed to generate sufficient quantities of isotope-labeled proteins for high-resolution NMR studies. Recently, the interaction between the prodomain region of subtilisin and an active, mutant form of the mature enzyme has been exploited to develop a cleavable affinity tag fusion system for one-step generation and purification of full-length soluble proteins obtained by inducible prokaryotic expression. As a first step towards applying high-resolution NMR methods to study heterotrimeric G-protein {alpha}-subunit (G{sub {alpha}}) conformation and dynamics, the utility of this subtilisin prodomain fusion system for expressing and purifying an isotope-labeled G{sub {alpha}} chimera ({approx}40 kDa polypeptide) has been tested. The results show that a prodomain fused G{sub {alpha}} chimera can be expressed to levels approaching 6-8 mg/l in minimal media and that the processed, mature protein exhibits properties similar to those of G{sub {alpha}} isolated from natural sources. To assay for the functional integrity of the purified G{sub {alpha}} chimera at NMR concentrations and probe for changes in the structure and dynamics of G{sub {alpha}} that result from activation, {sup 15}N-HSQC spectra of the GDP/Mg{sup 2+} bound form of G{sub {alpha}} obtained in the absence and presence of aluminum fluoride, a well known activator of the GDP bound state, have been acquired. Comparisons of the {sup 15}N-HSQC spectra reveals a number of changes in chemical shifts of the {sup 1}HN, {sup 15}N crosspeaks that are discussed with respect to expected changes in the protein conformation associated with G{sub {alpha}} activation.

Dynamic. cap alpha. -transfer polarisation potentials and the large angle scattering of /sup 16/O + /sup 28/Si

Energy Technology Data Exchange (ETDEWEB)

Hussein, M S; Aleixo, A N; Canto, L F; Carrilho, P; Donangelo, R; Paula, L.S. de

1987-07-01

A closed expression is derived for the dynamic ..cap alpha..-transfer polarisation potential for heavy-ion elastic scattering. The back-angle angular distributions for the elastic scattering of /sup 16/O + /sup 28/Si obtained by adding this polarisation potential to the E-18 interaction are shown to be in good agreement with the data if an ..cap alpha..-transfer spectroscopic factor of 0.4 is used.

Modularity in protein structures: study on all-alpha proteins.

Science.gov (United States)

Khan, Taushif; Ghosh, Indira

2015-01-01

Modularity is known as one of the most important features of protein's robust and efficient design. The architecture and topology of proteins play a vital role by providing necessary robust scaffolds to support organism's growth and survival in constant evolutionary pressure. These complex biomolecules can be represented by several layers of modular architecture, but it is pivotal to understand and explore the smallest biologically relevant structural component. In the present study, we have developed a component-based method, using protein's secondary structures and their arrangements (i.e. patterns) in order to investigate its structural space. Our result on all-alpha protein shows that the known structural space is highly populated with limited set of structural patterns. We have also noticed that these frequently observed structural patterns are present as modules or "building blocks" in large proteins (i.e. higher secondary structure content). From structural descriptor analysis, observed patterns are found to be within similar deviation; however, frequent patterns are found to be distinctly occurring in diverse functions e.g. in enzymatic classes and reactions. In this study, we are introducing a simple approach to explore protein structural space using combinatorial- and graph-based geometry methods, which can be used to describe modularity in protein structures. Moreover, analysis indicates that protein function seems to be the driving force that shapes the known structure space.

Hantaan Virus Nucleocapsid Protein Binds to Importin alpha Proteins and Inhibits Tumor Necrosis Factor Alpha-Induced Activation of Nuclear Factor Kappa B

Science.gov (United States)

2008-11-19

Microbiology . All Rights Reserved. Hantaan Virus Nucleocapsid Protein Binds to Importin Proteins and Inhibits Tumor Necrosis Factor Alpha-Induced...Division, U.S. Army Medical Research Institute of Infectious Diseases, Fort Detrick, Maryland 21702,1 and Department of Microbiology , Mount Sinai...34–36. 32. Prescott , J., C. Ye, G. Sen, and B. Hjelle. 2005. Induction of innate immune response genes by Sin Nombre hantavirus does not require

Fanconi anemia protein, FANCG, is a phosphoprotein and is upregulated with FANCA after TNF-alpha treatment.

Science.gov (United States)

Futaki, M; Watanabe, S; Kajigaya, S; Liu, J M

2001-02-23

Fanconi anemia (FA) is a genetic syndrome characterized by bone marrow failure, birth defects, and a predisposition to malignancy. At this time, six FA genes have been identified, and several gene products have been found to interact in a protein complex. FA cells appear to overexpress the proinflammatory cytokine, tumor necrosis factor-alpha (TNF-alpha). We therefore examined the effects of TNF-alpha on the regulation of FA complementation group proteins, FANCG and FANCA. We found that treatment with TNF-alpha induced FANCG protein expression. FANCA was induced concurrently with FANCG, and the FANCA/FANCG complex was increased in the nucleus following TNF-alpha treatment. Inactivation of inhibitory kappa B kinase-2 modulated the expression of FANCG. We also found that both nuclear and cytoplasmic FANCG fractions were phosphorylated. These results show that FANCG is a phosphoprotein and suggest that the cellular accumulation of FA proteins is subject to regulation by TNF-alpha signaling.

Nanoparticles with entrapped α-tocopherol: synthesis, characterization, and controlled release

International Nuclear Information System (INIS)

Zigoneanu, Imola Gabriela; Astete, Carlos Ernesto; Sabliov, Cristina Mirela

2008-01-01

An emulsion evaporation method was used to synthesize spherical poly(DL-lactide-co-glycolide) (PLGA) nanoparticles with entrapped α-tocopherol. Two different surfactants were used: sodium dodecyl sulfate (SDS) and poly(vinyl alcohol) (PVA). For SDS nanoparticles, the size of the nanoparticles decreased significantly with the entrapment of α-tocopherol in the PLGA matrix, while the size of PVA nanoparticles remained unchanged. The polydispersity index after synthesis was under 0.100 for PVA nanoparticles and around 0.150 for SDS nanoparticles. The zeta potential was negative for all PVA nanoparticles. The entrapment efficiency of α-tocopherol in the polymeric matrix was approximately 89% and 95% for nanoparticles with 8% and 16% α-tocopherol theoretical loading, respectively. The residual PVA associated with the nanoparticles after purification was approximately 6% ( w/w relative to the nanoparticles). The release profile showed an initial burst followed by a slower release of the α-tocopherol entrapped inside the PLGA matrix. The release for nanoparticles with 8% α-tocopherol theoretical loading (86% released in the first hour) was faster than the release for the nanoparticles with 16% α-tocopherol theoretical loading (34% released in the first hour)

Distribution and evolutionary trends of photoprotective isoprenoids (xanthophylls and tocopherols) within the plant kingdom.

Science.gov (United States)

Esteban, Raquel; Olano, José M; Castresana, José; Fernández-Marín, Beatriz; Hernández, Antonio; Becerril, José M; García-Plazaola, José I

2009-04-01

The earliest land photosynthesis would have increased the risk of photo-oxidations and the demand of anti-oxidative protection. In this work, we aimed to determine the evolutionary trends in photoprotection across a wide representation of the plant kingdom and to verify whether the non-ubiquitous lutein-epoxide (Lx) cycle is a polyphyletic or an ancient character. Carotenoids and alpha-tocopherol (alpha-toc) were analysed by HPLC in 266 species. Phylogenetic analyses of the presence of photoprotective compounds and zeaxanthin-epoxidase (ZE) sequences were performed. Violaxanthin-cycle pigments (VAZ) and alpha-toc were taxonomically ubiquitous. Ancient groups showed higher contents of VAZ than vascular plants, while alpha-toc showed the opposite pattern. Lutein-epoxide was present in 45% of the species. It showed a remarkable variation across groups but with a clear increasing trend from algae to basal angiosperms. Lutein-epoxide was also related to woody trait and leaf longevity. No correlation between the presence of Lx and recurrent mutations in ZE sequences, including the duplications, was found. Thus, there is an evolutionary trend to increase the content of alpha-toc and to decrease the total amount of VAZ pigments. Absence of Lx in algae discards an ancestral origin. Present results are also inconsistent with a polyphyletic origin of Lx in angiosperms.

Biokinetics of dietary RRR-alpha-tocopherol in the male guinea pig at three dietary levels of vitamin C and two levels of vitamin E. Evidence that vitamin C does not spare vitamin E in vivo

International Nuclear Information System (INIS)

Burton, G.W.; Wronska, U.; Stone, L.; Foster, D.O.; Ingold, K.U.

1990-01-01

The net rates of uptake of new and loss of old 2R,4'R,8'R-alpha-tocopherol (RRR-alpha-TOH) have been measured in the blood and in nine tissues of male guinea pigs over an eight week period by feeding diets containing deuterium-labelled alpha-tocopheryl acetate (d6-RRR-alpha-TOAc). There was an initial two week lead-in period during which 24 animals [the high vitamin E (HE) group] received diets containing 36 mg of unlabelled (d0) RRR-alpha-TOAc and 250 mg of ascorbic acid per kg diet, while another 24 animals [the low vitamin E (LE) group] received diets containing 5 mg d0-RRR-alpha-TOAc and 250 mg ascorbic acid per kg diet. The HE group was then divided into three equal subgroups, which were fed diets containing 36 mg d6-RRR-alpha-TOAc and 5000 mg [the high vitamin C (HEHC) subgroup], 250 mg [the normal vitamin C (HENC) subgroup] and 50 mg [the low vitamin C (HELC) subgroup] ascorbic acid per kg diet. One animal from each group was sacrificed each week and the blood and tissues were analyzed for d0- and d6-RRR-alpha-TOH by gas chromatography-mass spectrometry. The LE group was similarly divided into three equal subgroups with animals receiving diets containing 5 mg d6-RRR-alpha-TOAc and 5,000 mg (LEHC), 250 mg (LENC) and 50 mg (LELC) ascorbic acid per kg diet with a similar protocol being followed for sacrifice and analyses. In the HE group the total (d0(-) + d6-) RRR-alpha-TOH concentrations in blood and tissues remained essentially constant over the eight week experiment, whereas in the LE group the total RRR-alpha-TOH concentrations declined noticeably. There were no significant differences in the concentrations of old d0-RRR-alpha-TOH nor in the concentrations of new d6-RRR-alpha-TOH found in any tissue at a particular time between the HEHC, HENC and HELC subgroups, nor between the LEHC, LENC and LELC subgroups

Protein adsorption on low temperature alpha alumina films for surgical instruments

Energy Technology Data Exchange (ETDEWEB)

Cloud, A.N., E-mail: acloud@uark.ed [University of Arkansas, Fayetteville, AR 72701 (United States); Kumar, S. [Ian Wark Research Institute, University of South Australia, Mawson Lakes, Adelaide, SA 5095 (Australia); Kavdia, M.; Abu-Safe, H.H.; Gordon, M.H. [University of Arkansas, Fayetteville, AR 72701 (United States)

2009-08-31

Bulk alumina has been shown to exhibit reduced protein adsorption, a property that can be exploited for developing alumina-coated surgical instruments and devices. Alpha alumina thin films were deposited on surgical stainless steel substrates to investigate the adsorption of a model protein (BSA, bovine serum albumin). The films were deposited at 480 {sup o}C by AC inverted cylindrical magnetron sputtering. Films were obtained at 6 kW and 50% oxygen partial pressure by volume. The presence of alpha-phase alumina has been shown by transmission electron microscopy. Results indicate that there was a 50% reduction in protein adsorption for samples with the alumina coating compared to those with no coating.

Interactions between an alpha-helix and a beta-sheet. Energetics of alpha/beta packing in proteins.

Science.gov (United States)

Chou, K C; Némethy, G; Rumsey, S; Tuttle, R W; Scheraga, H A

1985-12-05

Conformational energy computations have been carried out to determine the favorable ways of packing a right-handed alpha-helix on a right-twisted antiparallel or parallel beta-sheet. Co-ordinate transformations have been developed to relate the position and orientation of the alpha-helix to the beta-sheet. The packing was investigated for a CH3CO-(L-Ala)16-NHCH3 alpha-helix interacting with five-stranded beta-sheets composed of CH3CO-(L-Val)6-NHCH3 chains. All internal and external variables for both the alpha-helix and the beta-sheet were allowed to change during energy minimization. Four distinct classes of low-energy packing arrangements were found for the alpha-helix interacting with both the parallel and the anti-parallel beta-sheet. The classes differ in the orientation of the axis of the alpha-helix relative to the direction of the strands of the right-twisted beta-sheet. In the class with the most favorable arrangement, the alpha-helix is oriented along the strands of the beta-sheet, as a result of attractive non-bonded side-chain-side-chain interactions along the entire length of the alpha-helix. A class with nearly perpendicular orientation of the helix axis to the strands is also of low energy, because it allows similarly extensive attractive interactions. In the other two classes, the helix is oriented diagonally relative to the strands of the beta-sheet. In one of them, it interacts with the convex surface near the middle of the saddle-shaped twisted beta-sheet. In the other, it is oriented along the concave diagonal of the beta-sheet and, therefore, it interacts only with the corner regions of the sheet, so that this packing is energetically less favorable. The packing arrangements involving an antiparallel and a parallel beta-sheet are generally similar, although the antiparallel beta-sheet has been found to be more flexible. The major features of 163 observed alpha/beta packing arrangements in 37 proteins are accounted for in terms of the computed

Underlying neural alpha frequency patterns associated with intra-hemispheric inhibition during an interhemispheric transfer task.

Science.gov (United States)

Simon-Dack, Stephanie L; Kraus, Brian; Walter, Zachary; Smith, Shelby; Cadle, Chelsea

2018-05-18

Interhemispheric transfer measured via differences in right- or left-handed motoric responses to lateralized visual stimuli, known as the crossed-uncrossed difference (CUD), is one way of identifying patterns of processing that are vital for understanding the transfer of neural signals. Examination of interhemispheric transfer by means of the CUD is not entirely explained by simple measures of response time. Multiple processes contribute to wide variability observed in CUD reaction times. Prior research has suggested that intra-hemispheric inhibitory processes may be involved in regulation of speed of transfer. Our study examined electroencephalography recordings and time-locked alpha frequency activity while 18 participants responded to lateralized targets during performance of the Poffenberger Paradigm. Our results suggest that there are alpha frequency differences at fronto-central lateral electrodes based on target, hand-of-response, and receiving hemisphere. These findings suggest that early motoric inhibitory mechanisms may help explain the wide range of variability typically seen with the CUD. Copyright © 2018 Elsevier B.V. All rights reserved.

Membranes and mammalian glycolipid transferring proteins.

Science.gov (United States)

Tuuf, Jessica; Mattjus, Peter

2014-02-01

Glycolipids are synthesized in and on various organelles throughout the cell. Their trafficking inside the cell is complex and involves both vesicular and protein-mediated machineries. Most important for the bulk lipid transport is the vesicular system, however, lipids moved by transfer proteins are also becoming more characterized. Here we review the latest advances in the glycolipid transfer protein (GLTP) and the phosphoinositol 4-phosphate adaptor protein-2 (FAPP2) field, from a membrane point of view. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Determination of phospholipid transfer proteins in rat tissues by immunoassays

International Nuclear Information System (INIS)

Teerlink, T.

1983-01-01

Several quantitative immunoassays have been developed for two phospholipid transfer proteins from rat liver, i.e. the phosphatidylcholine transfer protein and the non-specific lipid transfer protein. The development of a double-antibody radioimmunoassay for the phosphatidylcholine transfer protein is described. The transfer protein was labelled with iodine-125 by the mild glucose oxidase-lactoperoxidase method. Although less than one tyrosine residue per molecule of transfer protein was labelled, only 20% of the labelled transfer protein was immunoprecipitable. This value could be increased to 80% by purifying the labelled protein by affinity chromatography on a column of anti-phosphatidylcholine transfer protein-IgG coupled to Sepharose 4B. The radioimmunoassay was used to determine the levels of phosphatidylcholine transfer protein in homogenates and 105 000 xg supernatants from various rat tissues as well as several Morris hepatomas. An enzyme immunoassay for the non-specific lipid transfer protein is also described. The antiserum that was raised especially by the author was cross-reactive with the non-specific lipid transfer protein present in 105 000 xg supernatants from human, mouse and bovine liver. The non-specific lipid transfer protein lost its immunoreactivity upon labelling with iodine-125 using different labelling techniques. Therefore, a regular radioimmunoassay could not be developed. The results of these different assays were compared. (Auth.)

Mixed tocopherols prevent mammary tumorigenesis by inhibiting estrogen action and activating PPAR-γ

Science.gov (United States)

Lee, Hong Jin; Ju, Jihyeung; Paul, Shiby; So, Jae-Young; DeCastro, Andrew; Smolarek, Amanda; Lee, Mao-Jung; Yang, Chung S.; Newmark, Harold L.; Suh, Nanjoo

2009-01-01

Purpose Tocopherols are lipophilic antioxidants present in vegetable oils. Although the antioxidant and anticancer activities of α-tocopherol (vitamin E) have been studied for decades, recent intervention studies with α-tocopherol have been negative for protection from cancer in humans. The tocopherols consist of 4 isoforms, α, β, γ, and δ variants, and recent attention is being made to other isoforms. In the present study, we investigated the inhibitory effect of a tocopherol mixture rich in γ- and δ-tocopherols against mammary tumorigenesis. Experimental Design Female Sprague Dawley rats were treated with N-methyl-N-nitrosourea (NMU), and then fed diets containing 0.1%, 0.3%, or 0.5% mixed tocopherols rich in γ- and δ-tocopherols for 9 weeks. Tumor burden and multiplicity were determined, and the levels of markers of inflammation, proliferation and apoptosis were evaluated in the serum and in mammary tumors. The regulation of nuclear receptor signaling by tocopherols was studied in mammary tumors and in breast cancer cells. Results Dietary administration of 0.1%, 0.3%, or 0.5% mixed tocopherols suppressed mammary tumor growth by 38%, 50%, or 80%, respectively. Tumor multiplicity was also significantly reduced in all three mixed tocopherol groups. Mixed tocopherols increased the expression of p21, p27, caspase-3 and peroxisome proliferator activated receptor-γ (PPAR-γ), and inhibited AKT and estrogen signaling in mammary tumors. Our mechanistic study found that γ- and δ-tocopherols, but not α-tocopherol, activated PPAR-γ and antagonized estrogen action in breast cancer. Conclusion The results suggest that γ- and δ-tocopherols may be effective agents for the prevention of breast cancer. PMID:19509159

Protective Effects of α-Tocopherol, γ-Tocopherol and Oleic Acid, Three Compounds of Olive Oils, and No Effect of Trolox, on 7-Ketocholesterol-Induced Mitochondrial and Peroxisomal Dysfunction in Microglial BV-2 Cells

Directory of Open Access Journals (Sweden)

Meryam Debbabi

2016-11-01

Full Text Available Lipid peroxidation products, such as 7-ketocholesterol (7KC, may be increased in the body fluids and tissues of patients with neurodegenerative diseases and trigger microglial dysfunction involved in neurodegeneration. It is therefore important to identify synthetic and natural molecules able to impair the toxic effects of 7KC. We determined the impact of 7KC on murine microglial BV-2 cells, especially its ability to trigger mitochondrial and peroxisomal dysfunction, and evaluated the protective effects of α- and γ-tocopherol, Trolox, and oleic acid (OA. Multiple complementary chemical assays, flow cytometric and biochemical methods were used to evaluate the antioxidant and cytoprotective properties of these molecules. According to various complementary assays to estimate antioxidant activity, only α-, and γ-tocopherol, and Trolox had antioxidant properties. However, only α-tocopherol, γ-tocopherol and OA were able to impair 7KC-induced loss of mitochondrial transmembrane potential, which is associated with increased permeability to propidium iodide, an indicator of cell death. In addition, α-and γ-tocopherol, and OA were able to prevent the decrease in Abcd3 protein levels, which allows the measurement of peroxisomal mass, and in mRNA levels of Abcd1 and Abcd2, which encode for two transporters involved in peroxisomal β-oxidation. Thus, 7KC-induced side effects are associated with mitochondrial and peroxisomal dysfunction which can be inversed by natural compounds, thus supporting the hypothesis that the composition of the diet can act on the function of organelles involved in neurodegenerative diseases.

Type 2 diabetes mellitus is associated with differential effects on plasma cholesteryl ester transfer protein and phospholipid transfer protein activities and concentrations

NARCIS (Netherlands)

Dullaart, RPF; De Vries, R; Scheek, L; Borggreve, SE; Van Gent, T; Dallinga-Thie, GM; Ito, M; Nagano, M; Sluiter, WJ; Hattori, H; Van Tol, A

Background: Human plasma contains two lipid transfer proteins, cholesteryl ester transfer protein (CETP) and phospholipid transfer protein (PLTP), which are crucial in reverse cholesterol transport. Methods: Plasma CETP and PLTP activity levels and concentrations in 16 type 2 diabetic patients and

Temperature dependence of autoxidation of perilla oil and tocopherol degradation.

Science.gov (United States)

Wang, Seonyeong; Hwang, Hyunsuk; Yoon, Sukhoo; Choe, Eunok

2010-08-01

Temperature dependence of the autoxidation of perilla oil and tocopherol degradation was studied with corn oil as a reference. The oils were oxidized in the dark at 20, 40, 60, and 80 degrees C. Oil oxidation was determined by peroxide and conjugated dienoic acid values. Tocopherols in the oils were quantified by HPLC. The oxidation of both oils increased with oxidation time and temperature. Induction periods for oil autoxidation decreased with temperature, and were longer in corn oil than in perilla oil, indicating higher sensitivity of perilla oil to oxidation. However, time lag for tocopherol degradation was longer in perilla oil, indicating higher stability of tocopherols in perilla oil than in corn oil. Activation energies for oil autoxidation and tocopherol degradation were higher in perilla oil (23.9 to 24.2, 9.8 kcal/mol, respectively) than in corn oil (12.5 to 15.8, 8.8 kcal/mol, respectively) indicating higher temperature-dependence in perilla oil. Higher stability of tocopherols in perilla oil was highly related with polyphenols. The study suggests that more careful temperature control is required to decrease the autoxidation of perilla oil than that of corn oil, and polyphenols contributed to the oxidative stability of perilla oil by protecting tocopherols from degradation, especially at the early stage of oil autoxidation.

Alpha-tocopherol and β-carotene in legume-grass mixtures as influenced by wilting, ensiling and type of silage additive

DEFF Research Database (Denmark)

Lindqvist, H; Nadeau, E; Jensen, Søren Krogh

2012-01-01

Effects of wilting, ensiling and type of additive on α-tocopherol and β-carotene contents in legume–grass mixtures were examined. Swards of birdsfoot trefoil + timothy (Bft + Ti), red clover + timothy (Rc + Ti) and red clover + meadow fescue (Rc + Mf) were harvested as a first regrowth in August...

Rapid Estimation of Tocopherol Content in Linseed and Sunflower Oils-Reactivity and Assay

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Tjaša Prevc

2015-08-01

Full Text Available The reactivity of tocopherols with 2,2-diphenyl-1-picrylhydrazyl (DPPH was studied in model systems in order to establish a method for quantifying vitamin E in plant oils. The method was optimized with respect to solvent composition of the assay medium, which has a large influence on the course of reaction of tocopherols with DPPH. The rate of reaction of α-tocopherol with DPPH is higher than that of γ-tocopherol in both protic and aprotic solvents. In ethyl acetate, routinely applied for the analysis of antioxidant potential (AOP of plant oils, reactions of tocopherols with DPPH are slower and concentration of tocopherols in the assay has a large influence on their molar reactivity. In 2-propanol, however, two electrons are exchanged for both α- and γ-tocopherols, independent of their concentration. 2-propanol is not toxic and is fully compatible with polypropylene labware. The chromatographically determined content of tocopherols and their molar reactivity in the DPPH assay reveal that only tocopherols contribute to the AOP of sunflower oil, whereas the contribution of tocopherols to the AOP of linseed oil is 75%. The DPPH assay in 2-propanol can be applied for rapid and cheap estimation of vitamin E content in plant oils where tocopherols are major antioxidants.

Rapid Estimation of Tocopherol Content in Linseed and Sunflower Oils-Reactivity and Assay.

Science.gov (United States)

Prevc, Tjaša; Levart, Alenka; Cigić, Irena Kralj; Salobir, Janez; Ulrih, Nataša Poklar; Cigić, Blaž

2015-08-13

The reactivity of tocopherols with 2,2-diphenyl-1-picrylhydrazyl (DPPH) was studied in model systems in order to establish a method for quantifying vitamin E in plant oils. The method was optimized with respect to solvent composition of the assay medium, which has a large influence on the course of reaction of tocopherols with DPPH. The rate of reaction of α-tocopherol with DPPH is higher than that of γ-tocopherol in both protic and aprotic solvents. In ethyl acetate, routinely applied for the analysis of antioxidant potential (AOP) of plant oils, reactions of tocopherols with DPPH are slower and concentration of tocopherols in the assay has a large influence on their molar reactivity. In 2-propanol, however, two electrons are exchanged for both α- and γ-tocopherols, independent of their concentration. 2-propanol is not toxic and is fully compatible with polypropylene labware. The chromatographically determined content of tocopherols and their molar reactivity in the DPPH assay reveal that only tocopherols contribute to the AOP of sunflower oil, whereas the contribution of tocopherols to the AOP of linseed oil is 75%. The DPPH assay in 2-propanol can be applied for rapid and cheap estimation of vitamin E content in plant oils where tocopherols are major antioxidants.

α-TOCOPHEROL β-OXIDATION LOCALIZED TO RAT LIVER MITOCHONDRIA

OpenAIRE

Mustacich, Debbie J.; Leonard, Scott W.; Patel, Neha K.; Traber, Maret G.

2009-01-01

Approximately 40% of Americans take dietary supplements, including vitamin E (α-tocopherol). Unlike other fat-soluble vitamins, α-tocopherol is not accumulated to toxic levels. Rather tissue levels are tightly regulated, in part via increased hepatic metabolism and excretion that could, theoretically, alter metabolism of drugs, environmental toxins and other nutrients. To date, in vivo subcellular location(s) of α-tocopherol metabolism have not been identified. The proposed pathway of α-tocop...

Simulation and thermodynamic modeling of the extraction of tocopherol from a synthetic mixture of tocopherol, squalene and CO2

Directory of Open Access Journals (Sweden)

M.F. Mendes

2000-12-01

Full Text Available Soybean oil is the most consumed vegetable oil in the world, representing 54% of the total world production. Brazil is the second country in the world that produces and export soybean seeds, almost 20%. One of the most important by-product of the soybean oil is the deodorizer distillate, commonly known as soybean sludge. This residue is rich in many high value compounds as tocopherols, squalene and sterols. Tocopherols are the major components in the deodorized distillated due to their characteristics as an antioxidant agent. So, the objective of this work is to study the concentration of tocopherols presented in this raw material, using the operational conditions obtained from the equilibrium data and using supercritical carbon dioxide as a solvent. The deodorizer distillate is a complex mixture of more than 200 components, so a synthetic mixture was chosen to represent the deodorizer distillate. The synthetic mixture used in this work is composed by tocopherols, fatty acids and squalene. The simulation was carried out using ASPEN+ simulator and the LCVM thermodynamic model was used to correlate the available equilibrium data.

On the transfer of serum proteins to the rat intestinal juice

DEFF Research Database (Denmark)

Andersen, Vibeke; Norén, Ove; Poulsen, Mona D

1994-01-01

The in vivo pattern of serum proteins in the rat small-intestinal juice was characterized by crossed immunoelectrophoresis. Immunoglobulins and albumin, alpha-1-antitrypsin, transferrin, and orosomucoid were present. Larger serum proteins were absent (ceruloplasmin, haptoglobin, alpha-1-macroglob...... proteins in the intestinal juice is a selective passage through the capillary wall followed by passive intercellular transport via delivery of the serum in the interstitial space during disintegration of the enterocytes....

[G-protein potentiates the activation of TNF-alpha on calcium-activated potassium channel in ECV304].

Science.gov (United States)

Lin, L; Zheng, Y; Qu, J; Bao, G

2000-06-01

Observe the effect of tumor necrosis factor-alpha (TNF-alpha) on calcium-activated potassium channel in ECV304 and the possible involvement of G-protein mediation in the action of TNF-alpha. Using the cell-attached configuration of patch clamp technique. (1) the activity of high-conductance calcium-activated potassium channel (BKca) was recorded. Its conductance is (202.54 +/- 16.62) pS; (2) the activity of BKca was potentiated by 200 U/ml TNF-alpha; (3) G-protein would intensify this TNF-alpha activation. TNF-alpha acted on vascular endothelial cell ECV304 could rapidly activate the activity of BKca. Opening of BKca resulted in membrane hyper-polarization which could increase electro-chemical gradient for the resting Ca2+ influx and open leakage calcium channel, thus resting cytoplasmic free Ca2+ concentration could be elevated. G-protein may exert an important regulation in this process.

Tocopherol-deficient rice plants display increased sensitivity to photooxidative stress.

Science.gov (United States)

Chen, Defu; Chen, Haiwei; Zhang, Luhua; Shi, Xiaoli; Chen, Xiwen

2014-06-01

Tocopherols are lipophilic antioxidants that are synthesized exclusively in photosynthetic organisms. Despite extensive in vivo characterization of tocopherol functions in plants, their functions in the monocot model plant, rice, remain to be determined. In this study, transgenic rice plants constitutively silenced for homogentisate phytyltransferase (HPT) and tocopherol cyclase (TC) activity were generated. Silencing of HPT and TC resulted in up to a 98 % reduction in foliar tocopherol content relative to the control plants, which was also confirmed by transcript level analysis. When grown under normal conditions, HPT and TC transgenics showed no distinctive phenotype relative to the control plants, except a slight reduction in plant height and a slight decrease in the first leaf length. However, when exposed to high light at low temperatures, HPT and TC transgenics had a significantly higher leaf yellowing index than the control plants. The tocopherol-deficient plants decreased their total individual chlorophyll levels, their chlorophyll a/b ratio, and the maximum photochemical efficiency of photosystem II, whereas increased lipid peroxidation levels relative to the control plants. Tocopherol deficiency had no effect on ascorbate biosynthesis, but induced glutathione, antheraxanthin, and particularly zeaxanthin biosynthesis for compensation under stressful conditions. However, despite these compensation mechanisms, HPT and TC transgenics still exhibited altered phenotypes under high light at low temperatures. Therefore, it is suggested that tocopherols cannot be replaced and play an indispensable role in photoprotection in rice.

Development of Novel Formulations to Enhance in Vivo Transdermal Permeation of Tocopherol

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Nada Aly H.

2014-09-01

Full Text Available Tocopherol represents a big challenge for transdermal permeation owing to its extreme hydrophobicity and large molecular mass. The aim of the present study was to develop alpha-tocopherol (T topical formulations and evaluate their ex vivo and in vivo permeation. Franz diffusion cells were used for ex vivo permeation, and neonatal rats were used for in vivo permeation. Seven gel formulations and 21 liquid formulations were investigated for physical stability, viscosity and permeation of T. Analysis of T was performed by a validated HPLC method using a UV detector. The ex vivo permeation from gel and emulsion formulations was very poor (0.001-0.015 %. Highest permeation was observed from monophasic liquid formulations containing dimethyl sulfoxide (DMSO, tocopheryl polyethylene glycols (TPGs, propylene glycol, ethanol and 9.5 % T. The in vivo results demonstrated higher retention in the epidermis compared to subcutaneous tissues, 1377 and 1.13 μg g-1, respectively. Increasing T concentration from 4.8 to 9.5 % did not increase the amount permeated or % of T retained. It was concluded that simple solutions of T in the presence of DMSO and TPGs were more promising systems for effective transdermal permeation compared to gel, emulsion or oleaginous systems.

First-trimester plasma tocopherols are associated with risk of miscarriage in rural Bangladesh.

Science.gov (United States)

Shamim, Abu Ahmed; Schulze, Kerry; Merrill, Rebecca D; Kabir, Alamgir; Christian, Parul; Shaikh, Saijuddin; Wu, Lee; Ali, Hasmot; Labrique, Alain B; Mehra, Sucheta; Klemm, Rolf D W; Rashid, Mahbubur; Sungpuag, Pongtorn; Udomkesmalee, Emorn; West, Keith P

2015-02-01

Tocopherols were discovered for their role in animal reproduction, but little is known about the contribution of deficiencies of vitamin E to human pregnancy loss. We sought to determine whether higher first-trimester concentrations of α-tocopherol and γ-tocopherol were associated with reduced odds of miscarriage (pregnancy losses tocopherol (tocopherol (tocopherol distribution in women who did not miscarry). In all women, plasma α- and γ-tocopherol concentrations were low [median (IQR): 10.04 μmol/L (8.07-12.35 μmol/L) and 0.66 μmol/L (0.50-0.95 μmol/L), respectively]. In a logistic regression analysis that was adjusted for cholesterol and the other tocopherol, low α-tocopherol was associated with an OR of 1.83 (95% CI: 1.04, 3.20), whereas a low γ-tocopherol concentration was associated with an OR of 0.62 (95% CI: 0.41, 0.93) for miscarriage. Subgroup analyses revealed that opposing ORs were evident only in women with BMI (in kg/m(2)) ≥18.5 and serum ferritin concentration ≤150 μg/L, although low BMI and elevated ferritin conferred stronger risk of miscarriage. In pregnant women in rural Bangladesh, low plasma α-tocopherol was associated with increased risk of miscarriage, and low γ-tocopherol was associated with decreased risk of miscarriage. Maternal vitamin E status in the first trimester may influence risk of early pregnancy loss. The JiVitA-1 study, from which data for this report were derived, was registered at clinicaltrials.gov as NCT00198822. © 2015 American Society for Nutrition.

Macrophage inflammatory protein-1alpha: a link between innate immunity and familial Mediterranean fever?

Science.gov (United States)

Dizdar, Omer; Kalyoncu, Umut; Karadag, Omer; Akdogan, Ali; Kiraz, Sedat; Ertenli, Ihsan; Barista, Ibrahim; Calguneri, Meral

2007-01-01

The aim of this study is to investigate the relationship between chemokines and the inflammation in Familial Mediterranean Fever (FMF). Forty-nine patients with FMF (41 in remission and 8 in acute attack period) and 20 healthy controls were included in the study. Serum levels of macrophage inflammatory protein-1alpha (MIP-1alpha) were assessed in the patients and the controls, along with other parameters of disease activity, i.e., fibrinogen, C-reactive protein and erythrocyte sedimentation rate. Serum MIP-1alpha levels of the patients with FMF in acute attack period were significantly higher than the patients in remission and healthy controls (p=0.02 and p=0.038, respectively). MIP-1alpha levels were weakly correlated with CRP (r=0.32, p=0.032) levels. MIP-1alpha may have a role in the pathogenesis of FMF attacks. MIP-1alpha and other chemokines may constitute a link between the innate immune system and FMF.

Detection of proteins on blot transfer membranes.

Science.gov (United States)

Sasse, Joachim; Gallagher, Sean R

2003-11-01

In the basic and alternate protocols of this unit, proteins are stained after electroblotting from polyacrylamide gels to blot transfer membranes. If the samples of interest are electrophoresed in duplicate and transferred to a blot transfer membrane, half of the membrane can be stained to determine the efficiency of transfer to the membrane and the other half can be used for immunoblotting (i.e., western blotting). Detection limits of each staining method are given along with a list of compatible blot transfer membranes and gels. A support protocol describes a method for alkali treatment that enhances subsequent staining of bound proteins.

FORTRAN data files transference from VAX/VMS to ALPHA/UNIX; Traspaso de ficheros FORTRAN de datos de VAX/VMS a ALPHA/UNIX

Energy Technology Data Exchange (ETDEWEB)

Sanchez, E.; Milligen, B. Ph van [CIEMAT (Spain)

1997-09-01

Several tools have been developed to access the TJ-IU databases, which currently reside in VAX/VMS servers, from the TJ-II Data Acquisition System DEC ALPHA 8400 server. The TJ-I/TJ-IU databases are not homogeneous and contain several types of data files, namely, SADE, CAMAC and FORTRAN unformatted files. The tools presented in this report allow one to transfer CAMAC and those FORTRAN unformatted files defined herein, from a VAX/VMS server, for data manipulation on the ALPHA/Digital UNIX server. (Author)

Increased antioxidant efficacy of tocopherols by surfactant solubilization in oil-in-water emulsions.

Science.gov (United States)

Kiralan, S Sezer; Doğu-Baykut, Esra; Kittipongpittaya, Ketinun; McClements, David Julian; Decker, Eric A

2014-10-29

The physical location of antioxidants in oil-in-water emulsions can have significant influence on their free radical scavenging activity and ability to inhibit lipid oxidation. We aimed to determine the effect of the surfactant concentration on the partitioning behavior of tocopherols (α, γ, and δ) in oil-in-water emulsions. Tween 20 (0.1, 0.5, and 1%) increased the partitioning of the tocopherols into the aqueous phase via the formation of Tween 20-tocopherol comicelles. Partitioning behavior of antioxidants was dependent upon the number of methyl groups and, thus, polarity of the tocopherols. δ-Tocopherol (one methyl group) exhibited the most partitioning into the aqueous phase, while α-tocopherol (three methyl groups) had the lowest partitioning. Lipid oxidation studies showed that the antioxidant activity of δ- and α-tocopherols was enhanced by adding Tween 20 to oil-in-water emulsions. This work suggests that surfactant micelles could increase the antioxidant activity of tocopherols by changing their physical location.

Improving protein resistance of {alpha}-Al{sub 2}O{sub 3} membranes by modification with POEGMA brushes

Energy Technology Data Exchange (ETDEWEB)

He Huating [State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemistry and Chemical Engineering, Nanjing University of Technology, Nanjing 210009 (China); Jing Wenheng, E-mail: jingwenheng@yahoo.com.cn [State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemistry and Chemical Engineering, Nanjing University of Technology, Nanjing 210009 (China); Xing Weihong; Fan Yiqun [State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemistry and Chemical Engineering, Nanjing University of Technology, Nanjing 210009 (China)

2011-11-15

A kind of protein-resistant ceramic membrane is prepared by grafting poly(oligo (ethylene glycol) methyl ether methacrylate) (POEGMA) brushes onto the surfaces and pore walls of {alpha}-Al{sub 2}O{sub 3} membrane (AM) by surface-initiated atom-transfer radical polymerization (SI-ATRP). Contact-angle, Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA) and field-emission scanning electron microscopy (FESEM) were measured to confirm that the surfaces and pore walls of the ceramic porous membranes have been modified by the brushes with this method successfully. The protein interaction behavior with the POEGMA modified membranes (AM-POEGMA) was studied by the model protein of bovine serum albumin (BSA). A protein-resistant mechanism of AM-POEGMA was proposed to describe an interesting phenomenon discovered in the filtration experiment, in which the initial flux filtrating BSA solution is higher than the pure water flux. The fouling of AM-POEGMA was easier to remove than AM for the action of POEGMA brushes, indicated that the ceramic porous membranes modified with POEGMA brushes exhibit excellent protein resistance.

Mapping of the mouse actin capping protein {alpha} subunit genes and pseudogenes

Energy Technology Data Exchange (ETDEWEB)

Hart, M.C.; Korshunova, Y.O.; Cooper, J.A. [Washington Univ. School of Medicine, St. Louis, MO (United States)

1997-02-01

Capping protein (CP), a heterodimer of {alpha} and {beta} subunits, is found in all eukaryotes. CP binds to the barbed ends of actin filaments in vitro and controls actin assembly and cell motility in vivo. Vertebrates have three {alpha} isoforms ({alpha}1, {alpha}2, {alpha}3) produced from different genes, whereas lower organisms have only one gene and one isoform. We isolated genomic clones corresponding to the a subunits of mouse CP and found three {alpha}1 genes, two of which are pseudogenes, and a single gene for both {alpha}2 and {alpha}3. Their chromosomal locations were identified by interspecies backcross mapping. The {alpha}1 gene (Cappa1) mapped to Chromosome 3 between D3Mit11 and D3Mit13. The {alpha}1 pseudogenes (Cappa1-ps1 and Cappa1-ps2) mapped to Chromosomes 1 and 9, respectively. The {alpha}2 gene (Cappa2) mapped to Chromosome 6 near Ptn. The {alpha}3 gene (Cappa3) also mapped to Chromosome 6, approximately 68 cM distal from Cappa2 near Kras2. One mouse mutation, de, maps in the vicinity of the {alpha}1 gene. No known mouse mutations map to regions near the {alpha}2 or {alpha}3 genes. 29 refs., 3 figs., 1 tab.

A Comparison of Natural (D-α-tocopherol and Synthetic (DL-α-tocopherol Acetate Vitamin E Supplementation on the Growth Performance, Meat Quality and Oxidative Status of Broilers

Directory of Open Access Journals (Sweden)

K. Cheng

2016-05-01

Full Text Available The present study was conducted to compare the supplementation of natural (D-α-tocopherol and synthetic (DL-α-tocopherol acetate vitamin E on the growth performance, meat quality, muscular antioxidant capacity and genes expression related to oxidative status of broilers. A total of 144 1 day-old Arbor Acres broiler chicks were randomly allocated into 3 groups with 6 replicates of 8 birds each. Birds were given a basal diet (control group, and basal diet supplemented with either 20 IU D-α-tocopherol or DL-α-tocopherol acetate for 42 days, respectively. The results indicated that treatments did not alter growth performance of broilers (p>0.05. Compared with the control group, concentration of α-tocopherol in the breast muscle was increased by the supplementation of vitamin E (p0.05. It was concluded that vitamin E supplementation, especially the natural vitamin E, can enhance the retention of muscular α-tocopherol, improve meat quality and muscular antioxidant capacity of broilers.

Supplementation of a γ-tocopherol-rich mixture of tocopherols in healthy men protects against vascular endothelial dysfunction induced by postprandial hyperglycemia.

Science.gov (United States)

Mah, Eunice; Noh, Sang K; Ballard, Kevin D; Park, Hea Jin; Volek, Jeff S; Bruno, Richard S

2013-01-01

Postprandial hyperglycemia induces oxidative stress responses, impairs vascular endothelial function (VEF) and increases the risk of cardiovascular disease. We hypothesized that the antioxidant and anti-inflammatory activities of a γ-tocopherol-rich mixture of tocopherols (γ-TmT) would protect against vascular dysfunction that is otherwise caused by postprandial hyperglycemia by decreasing oxidative stress and proinflammatory responses, and improving nitric oxide (NO•) homeostasis. In a randomized, crossover study, healthy men (n=15; 21.8 ± 0.8 years) completed a fasting oral glucose challenge (75 g) with or without prior supplementation of γ-TmT (5 days). Brachial artery flow-mediated dilation (FMD), plasma glucose, insulin, antioxidants, malondialdehyde (MDA), inflammatory proteins, arginine and asymmetric dimethylarginine (ADMA) were measured at regular intervals during a 3-h postprandial period. Supplementation of γ-TmT increased (P.05). Postprandial FMD decreased 30%-44% (P<.05) following glucose ingestion, but was maintained with γ-TmT. Supplementation of γ-TmT also attenuated postprandial increases in MDA that occurred following glucose ingestion. Plasma arginine decreased (P<.05) in both trials to a similar extent regardless of γ-TmT supplementation. However, the ratio of ADMA/arginine increased time-dependently in both trials (P<.05), but to a lesser extent following γ-TmT supplementation (P<.05). Inflammatory proteins were unaffected by glucose ingestion or γ-TmT. Collectively, these findings support that short-term supplementation of γ-TmT maintains VEF during postprandial hyperglycemia possibly by attenuating lipid peroxidation and disruptions in NO• homeostasis, independent of inflammation. Published by Elsevier Inc.

Biodegradable films containing α-tocopherol/β-cyclodextrin complex

International Nuclear Information System (INIS)

Motta, Caroline; Martelli, Silvia M.; Soldi, Valdir; Barreto, Pedro L.M.

2011-01-01

The growing environmental concern about pollution and the need to reduce dependence of plastic industry in relation to non-renewable resources has increased the interest of both researchers and industry in the use of biopolymers. In this work β-cyclodextrin/α-tocopherol complexes were prepared and characterized. In order to obtain polymeric active biofilms, the β-cyclodextrin/α-tocopherol complex was incorporated into a polymeric matrix of carboxymethylcellulose. The β-cyclodextrin/α-tocopherol complex was characterized through of X-ray diffraction and thermogravimetric analysis. The physicochemical properties of the films incorporated with the complex were evaluated through mechanical and colorimetric analysis and moisture sorption isotherm. (author)

Uptake of intact TPGS (d-alpha-tocopheryl polyethylene glycol 1000 succinate) a water-miscible form of vitamin E by human cells in vitro

International Nuclear Information System (INIS)

Traber, M.G.; Thellman, C.A.; Rindler, M.J.; Kayden, H.J.

1988-01-01

The mechanism by which TPGS (alpha-tocopheryl succinate esterified to polyethylene glycol 1000 [PEG 1000]) delivers tocopherol (vitamin E) was studied in human fibroblasts and erythrocytes and a human intestinal cell line, Caco-2. The total cellular tocopherol content of saponified samples of fibroblasts or Caco-2 incubated for 4 h with TPGS (4 mumol/L) increased 10-fold without an increase in the free tocopherol content of nonsaponified samples. A 24-h incubation resulted in a free tocopherol content of approximately 20%, suggesting that intracellular hydrolysis of ester bonds had occurred. The increase in total tocopherol content after a 4-h incubation with TPGS was temperature dependent; no change was measurable at 4 degrees C. Addition of metabolic inhibitors during incubation with TPGS at 37 degrees C did not prevent the increase. [ 14 C]TPGS (synthesized from [ 14 C]PEG 1000) was taken up by Caco-2 cells but [ 14 C]PEG 1000 was not. The intracellular total tocopherol (pmol) equaled the [ 14 C]TPGS (pmol), unequivocally demonstrating uptake of the intact TPGS molecule

Tocopherol Supplementation Reduces NO Production and Pulmonary Inflammatory Response to Bleomycin

Science.gov (United States)

Shi, Jin Dong; Golden, Thea; Guo, Chang-Jiang; Tu, Shui Ping; Scott, Pamela; Lee, Mao-Jung; Yang, Chung S.; Gow, Andrew J.

2013-01-01

Bleomycin causes acute lung injury through production of reactive species and initiation of inflammation. Previous work has shown alteration to the production of reactive oxygen species results in attenuation of injury. Vitamin E, in particular, γ-tocopherol, isoform, has the potential to scavenge reactive oxygen and nitrogen species. This study examines the utility of dietary supplementation with tocopherols in reducing bleomycin-mediated acute lung injury. Male C57BL6/J mice were intratracheally instilled with PBS or 2 units/kg bleomycin. Animals were analyzed 3 and 8 days post instillation at the cellular, tissue, and organ levels. Results showed successful delivery of tocopherols to the lung via dietary supplementation. Also, increases in reactive oxygen and nitrogen species due to bleomycin are normalized in those mice fed tocopherol diet. Injury was not prevented but inflammation progression was altered, in particular macrophage activation and function. Inflammatory scores based on histology demonstrate limited progression of inflammation in those mice treated with bleomycin and fed tocopherol diet compared to control diet. Upregulation of enzymes and cytokines involved in pro-inflammation were limited by tocopherol supplementation. Day 3 functional changes in elastance in response to bleomycin are prevented, however, 8 days post injury the effect of the tocopherol diet is lost. The effect of tocopherol supplementation upon the inflammatory process is demonstrated by a shift in the phenotype of macrophage activation. The effect of these changes on resolution and the progression of pulmonary fibrosis has yet to be elucidated. PMID:23669183

Determination of fatty acid, tocopherol and phyto sterol contents of the oils of various poppy (Papaver somniferum L.) seeds.

Energy Technology Data Exchange (ETDEWEB)

Enric, H.; Tekin, A.; Musa Ozcan, M.

2009-07-01

The fatty acid, tocopherol and sterol contents of the oils of several poppy seeds were investigated. The main fatty acids in poppy seed oils were linoleic (687.6-739.2 g kg{sup -}1), oleic (141.3-192.8 g kg{sup -}1) and palmitic (76.8-92.8 g kg{sup -}1). The oils contained an appreciable amount of {gamma}-tocopherol (195.37-280.85 mg kg{sup -}1), with a mean value of 261.31 mg kg-1 and {alpha}-tocopherol (21.99-45.83 mg kg{sup -}1), with a mean value of 33.03 mg kg{sup -}1. The concentrations of total sterol ranged from 1099.84 mg kg{sup -}1 (K.pembe) to 4816.10 mg kg-1 (2. sinif beyaz), with a mean value of 2916.20 mg kg{sup -}1. The major sterols were {beta}-sitosterol, ranging from 663.91 to 3244.39 mg kg{sup -}1; campesterol, ranging from 228.59 to 736.50 mg kg{sup -}1; and {delta}{sup 5}-avenasterol, ranging from 103.90 to 425.02 mg kg{sup -}1. The studied varieties of poppy seeds from Turkey were found to be a potential source of valuable oil. (Author) 31 refs.

TIF1alpha: a possible link between KRAB zinc finger proteins and nuclear receptors

DEFF Research Database (Denmark)

Le Douarin, B; You, J; Nielsen, Anders Lade

1998-01-01

Ligand-induced gene activation by nuclear receptors (NRs) is thought to be mediated by transcriptional intermediary factors (TIFs), that interact with their ligand-dependent AF-2 activating domain. Included in the group of the putative AF-2 TIFs identified so far is TIF1alpha, a member of a new...... family of proteins which contains an N-terminal RBCC (RING finger-B boxes-coiled coil) motif and a C-terminal bromodomain preceded by a PHD finger. In addition to these conserved domains present in a number of transcriptional regulatory proteins, TIF1alpha was found to contain several protein......-protein interaction sites. Of these, one specifically interacts with NRs bound to their agonistic ligand and not with NR mutants that are defective in the AF-2 activity. Immediately adjacent to this 'NR box', TIF1alpha contains an interaction site for members of the chromatin organization modifier (chromo) family, HP...

Cytoprotective effect of tocopherols in hepatocytes cultured with polyunsaturated fatty acids

DEFF Research Database (Denmark)

Mikkelsen, L.; Hansen, Harald S.; Grunnet, N.

1994-01-01

When highly unsaturated fatty acids are added to cell cultures, it can become important to include antioxidants in the culture medium to prevent cytotoxic peroxidation. To find an optimal antioxidant for this purpose, the effect of 50 µM a-tocopherol, ¿-tocopherol, a-tocopheryl acetate, a...... of thiobarbituric acid reactive substances in the cultures was also measured. a-Tocopheryl acid succinate was found to be the most effective cytoprotective compound, followed by N,N'-diphenyl-1,4-phenylenediamine, a- tocopherol, ¿-tocopherol and a-tocopheryl acetate, and a-tocopheryl phosphate was without effect....

Acute moderate elevation of TNF-{alpha} does not affect systemic and skeletal muscle protein turnover in healthy humans

DEFF Research Database (Denmark)

Petersen, Anne Marie; Plomgaard, Peter; Fischer, Christian P

2009-01-01

-alpha infusion (rhTNF-alpha). We hypothesize that TNF-alpha increases human muscle protein breakdown and/or inhibit synthesis. Subjects and Methods: Using a randomized controlled, crossover design post-absorptive healthy young males (n=8) were studied 2 hours under basal conditions followed by 4 hours infusion...... with the phenylalanine 3-compartment model showed similar muscle synthesis, breakdown and net muscle degradation after 2 hours basal and after 4 hours Control or rhTNF-alpha infusion. Conclusion: This study is the first to show in humans that TNF-alpha does not affect systemic and skeletal muscle protein turnover, when......Context: Skeletal muscle wasting has been associated with elevations in circulating inflammatory cytokines, in particular TNF-alpha. Objective: In this study, we investigated whether TNF-alpha affects human systemic and skeletal muscle protein turnover, via a 4 hours recombinant human TNF...

Prediagnostic serum tocopherol levels and the risk of non-hodgkin lymphoma: the multiethnic cohort.

Science.gov (United States)

Morimoto, Yukiko; Ollberding, Nicholas J; Cooney, Robert V; Wilkens, Lynne R; Franke, Adrian A; Le Marchand, Loïc; Goodman, Marc T; Hernandez, Brenda Y; Kolonel, Laurence N; Maskarinec, Gertraud

2013-11-01

Compromised immunity and chronic inflammation are thought to contribute to the development of non-Hodgkin lymphoma (NHL). Because tocopherols protect cells through antioxidant mechanisms, they may play a role in NHL etiology. This nested case-control study within the Multiethnic Cohort examined the association of prediagnostic serum tocopherols levels measured in 271 NHL cases and 538 matched controls by high-pressure liquid chromatography/photodiode array detection with NHL risk. Conditional logistic regression was used to calculate ORs and 95% confidence intervals (CI). We observed U-shaped associations with NHL for total and α-tocopherols [Ptrend tocopherols, which consisted primarily of α-tocopherol, were 0.41 (0.25-0.68), 0.52 (0.32-0.85), 0.39 (0.23-0.65), and 0.78 (0.47-1.29) for the second to fifth quintiles as compared with the first. The risk estimates were similar for α-tocopherol but nonsignificant for β- and γ-tocopherol combined and for γ-tocopherol. Adjustment for serum lipids strengthened the nonlinear associations for total and α-tocopherols. Serum total tocopherol levels were higher for vitamin E supplement users at cohort entry than nonusers (21.32 ± 9.04 vs. 17.72 ± 7.43 μg/mL; P tocopherols, at levels likely reflecting adequate dietary intakes, may be protective against NHL, whereas higher intakes from supplementation may not be beneficial. The association between serum tocopherol levels and NHL risk provides possible new insights into the etiology of NHL. ©2013 AACR.

Fatty acid, tocopherol and squalene contents of Rosaceae seed oils.

Science.gov (United States)

Matthaus, Bertrand; Özcan, Mehmet Musa

2014-12-01

The aim of current study is to establish the composition of these seeds belong to Rosaceae family with respect to fatty acid, tocopherol and squalene content. The oil contents of seeds varied between 3.49 (Cotoneaster bullatus) to 46.15 g/100 g (Prunus tenella). The main fatty acids of seed oils were oleic (6.50 - 67.11 %), linoleic (22.08 - 68.62 %) and 20:1n-7 (0.10 - 61.59 %). As observed, the oils of seed were rich in linoleic and oleic acids. Total tocopherol contents ranged between 7.06 mg/100 g (Prunus tenella) to 165.74 mg/100 g (Potentilla glandulosa ssp. pseudorupestris). The major tocopherols were γ-tocopherol, ranging from 2.08 mg/100 g to 106.01 mg/100 g; α-tocopherol ranging from 2.86 mg100 g to 74.26 mg/100 g and δ-tocopherol ranging used in this experiment were found between 0.02 mg/100 g (Alchemilla caucasica) to o.29 mg/100 g (Cotoneaster simonsii). These results show that Rosaceae seed oils can be a potential saurce of valuable oil which might be useful for the evaluation of dietary information in important food crops and other industrial applications.

Free radicals in alcoholic myopathy: indices of damage and preventive studies.

Science.gov (United States)

Preedy, Victor R; Adachi, Junko; Asano, Migiwa; Koll, Michael; Mantle, David; Niemela, Onni; Parkkila, Seppo; Paice, Alistair G; Peters, Timothy; Rajendram, Rajkumar; Seitz, Helmut; Ueno, Yasuhiro; Worrall, Simon

2002-04-15

Chronic alcoholic myopathy affects up to two-thirds of all alcohol misusers and is characterized by selective atrophy of Type II (glycolytic, fast-twitch, anaerobic) fibers. In contrast, the Type I fibers (oxidative, slow-twitch, aerobic) are relatively protected. Alcohol increases the concentration of cholesterol hydroperoxides and malondialdehyde-protein adducts, though protein-carbonyl concentration levels do not appear to be overtly increased and may actually decrease in some studies. In alcoholics, plasma concentrations of alpha-tocopherol may be reduced in myopathic patients. However, alpha-tocopherol supplementation has failed to prevent either the loss of skeletal muscle protein or the reductions in protein synthesis in alcohol-dosed animals. The evidence for increased oxidative stress in alcohol-exposed skeletal muscle is thus inconsistent. Further work into the role of ROS in alcoholic myopathy is clearly warranted.

Role of macrophage inflammatory protein-1alpha in T-cell-mediated immunity to viral infection

DEFF Research Database (Denmark)

Madsen, Andreas N; Nansen, Anneline; Christensen, Jan P

2003-01-01

The immune response to lymphocytic choriomeningitis virus in mice lacking macrophage inflammatory protein-1alpha (MIP-1alpha) was evaluated. Generation of virus-specific effector T cells is unimpaired in MIP-1alpha-deficient mice. Furthermore, MIP-1alpha is not required for T-cell-mediated virus...... control or virus-induced T-cell-dependent inflammation. Thus, MIP-1alpha is not mandatory for T-cell-mediated antiviral immunity....

Unintended changes in protein expression revealed by proteomic analysis of seeds from transgenic pea expressing a bean alpha-amylase inhibitor gene.

Science.gov (United States)

Chen, Hancai; Bodulovic, Greg; Hall, Prudence J; Moore, Andy; Higgins, Thomas J V; Djordjevic, Michael A; Rolfe, Barry G

2009-09-01

Seeds of genetically modified (GM) peas (Pisum sativum L.) expressing the gene for alpha-amylase inhibitor-1 (alphaAI1) from the common bean (Phaseolus vulgaris L. cv. Tendergreen) exhibit resistance to the pea weevil (Bruchus pisorum). A proteomic analysis was carried out to compare seeds from GM pea lines expressing the bean alphaAI1 protein and the corresponding alphaAI1-free segregating lines and non-GM parental line to identify unintended alterations to the proteome of GM peas due to the introduction of the gene for alphaAI1. Proteomic analysis showed that in addition to the presence of alphaAI1, 33 other proteins were differentially accumulated in the alphaAI1-expressing GM lines compared with their non-GM parental line and these were grouped into five expression classes. Among these 33 proteins, only three were found to be associated with the expression of alphaAI1 in the GM pea lines. The accumulation of the remaining 30 proteins appears to be associated with Agrobacterium-mediated transformation events. Sixteen proteins were identified after MALDI-TOF-TOF analysis. About 56% of the identified proteins with altered accumulation in the GM pea were storage proteins including legumin, vicilin or convicilin, phaseolin, cupin and valosin-containing protein. Two proteins were uniquely expressed in the alphaAI1-expressing GM lines and one new protein was present in both the alphaAI1-expressing GM lines and their alphaAI1-free segregating lines, suggesting that both transgenesis and transformation events led to demonstrable changes in the proteomes of the GM lines tested.

Synthesis of α-tocopherol-5-Me-D

International Nuclear Information System (INIS)

Corol, Delia; Mihaila, V.; Chiper, Diana

1999-01-01

Vitamin E is a group of eight different compounds having a methylate and hydroxylate oxygen ring condensed with a benzene molecule. Four of them, called tocopherols, have a saturated lateral chain deriving from phytol, while the tocotrienol compounds have the same chain and three double bonds. Vitamin E is essential for the reproduction process and intervenes in cellular oxidation processes, in muscular metabolism of creatinine and in carbon hydrate metabolism, facilitating the glycogen build-up in tissues. The labelling of vitamin E with deuterium is performed as follows: 1) Chloromethylation of γ-tocopherol to obtain α-tocopherol-5-Me-Cl; 2) Replacement of chlorine by deuterium in a dehalogenation catalytic reaction on Pd/C or Pd/CaCO 3 catalysts. The reaction scheme is given. The purification was performed by solvent selective extraction. The labelled compound characterization was carried out by NMR. (authors)

Chemopreventive activity of vitamin E in breast cancer: a focus on γ- and δ-tocopherol.

Science.gov (United States)

Smolarek, Amanda K; Suh, Nanjoo

2011-11-01

Vitamin E consists of eight different variants: α-, β-, γ-, and δ-tocopherols (saturated phytyl tail) and α-, β-, γ-, and δ-tocotrienols (unsaturated phytyl tail). Cancer prevention studies with vitamin E have primarily utilized the variant α-tocopherol. To no avail, a majority of these studies focused on variant α-tocopherol with inconsistent results. However, γ-tocopherol, and more recently δ-tocopherol, have shown greater ability to reduce inflammation, cell proliferation, and tumor burden. Recent results have shown that γ-enriched mixed tocopherols inhibit the development of mammary hyperplasia and tumorigenesis in animal models. In this review, we discuss the possible differences between the variant forms, molecular targets, and cancer-preventive effects of tocopherols. We recommend that a γ-enriched mixture, γ- and δ-tocopherol, but not α-tocopherol, are promising agents for breast cancer prevention and warrant further investigation.

Controlled release of tocopherols from polymer blend films

Science.gov (United States)

Obinata, Noe

Controlled release packaging has great potential to increase storage stability of foods by releasing active compounds into foods continuously over time. However, a major limitation in development of this technology is the inability to control the release and provide rates useful for long term storage of foods. Better understanding of the factors affecting active compound release is needed to overcome this limitation. The objective of this research was to investigate the relationship between polymer composition, polymer processing method, polymer morphology, and release properties of active compounds, and to provide proof of principle that compound release is controlled by film morphology. A natural antioxidant, tocopherol was used as a model active compound because it is natural, effective, heat stable, and soluble in most packaging polymers. Polymer blend films were produced from combination of linear low density polyethylene (LLDPE) and high density polyethylene (HDPE), polypropylene (PP), or polystyrene (PS) with 3000 ppm mixed tocopherols using conventional blending method and innovative blending method, smart blending with a novel mixer using chaotic advection. Film morphologies were visualized with scanning electron microscopy (SEM). Release of tocopherols into 95% ethanol as a food simulant was measured by UV/Visible spectrophotometry or HPLC, and diffusivity of tocopherols in the polymers was estimated from this data. Polymer composition (blend proportions) and processing methods have major effects on film morphology. Four different types of morphologies, dispersed, co-continuous, fiber, and multilayer structures were developed by either conventional extrusion or smart blending. With smart blending of fixed polymer compositions, different morphologies were progressively developed with fixed polymer composition as the number of rod rotations increased, providing a way to separate effects of polymer composition and morphology. The different morphologies

Role of ascorbic acid and α tocopherol in alleviating salinity stress on flax plant (Linum usitatissimum L.

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Mervat Sh. Sadak

2014-03-01

Full Text Available Salinity is one of the environmental challenges in the world affecting on several physiological processes and the most limiting factor of plant productivity and quality. Two pot experiments were conducted at the wire house of National Research Centre, Cairo, Egypt during two successive seasons of 2010/2011 and 2011/2012 to assess the efficiency of two antioxidant vitamins (ascorbic acid at 1.13 and 2.27 mM or α tocopherol at 0.46 and 0.93 mM and/or salinity stress at (0.0, 3.08, 6.16, 9.23 ds/m on photosynthetic pigments, protein, carbohydrate, minerals, oil contents and yield as well as fatty acids composition of the yielded oils of three flax cultivars (Sakha 3, Giza 8 and Ariane. The data revealed that salinity stress caused significant and gradual decreases in total photosynthetic pigments, polysaccharides, total carbohydrates, total proteins and the uptake of Mg, K, Ca and P in the leaves of three flax cultivars with increasing salinity levels (3.08, 6.16, 9.23 ds/m. Otherwise, significant and gradual increase appeared in both Na and Cl. Ascorbic acid and α tocopherol at different concentrations caused significant increases in photosynthetic pigments, total carbohydrates and protein contents in the leaves of flax plants irrigated either with tap water or saline solution as compared with their corresponding controls. Exogenous application of ascorbic and α tocopherol at different concentrations exhibited decreases in Na and Cl whereas increases appeared in Mg, K, Ca and P relative to their corresponding control. Ascorbic acid (1.13 and 2.27 mM and α tocopherol (0.46 and 0.93 mM caused marked increases in yield and yield attributes of three flax cultivars either in plants irrigated with tap water or saline solution as compared to corresponding control. Ascorbic acid effects were more pronounced than α tocopherol effects. In addition, the higher level of two vitamins was more pronounced than the lower level. Regarding plants irrigated

Reduction and Methyl Transfer Kinetics of the Alpha Subunit from Acetyl-Coenzyme A Synthase

Energy Technology Data Exchange (ETDEWEB)

Xiangshi Tan; Christopher Sewell; Qingwu Yang; Paul A. Lindahl

2003-01-15

OAK-B135 Stopped-flow was used to evaluate the methylation and reduction kinetics of the isolated alpha subunit of acetyl-Coenzyme A synthase from Moorella thermoacetica. This catalytically active subunit contains a novel Ni-X-Fe4S4 cluster and a putative unidentified n =2 redox site called D. The D-site must be reduced for a methyl group to transfer from a corrinoid-iron-sulfur protein, a key step in the catalytic synthesis of acetyl-CoA. The Fe4S4 component of this cluster is also redox active, raising the possibility that it is the D-site or a portion thereof. Results presented demonstrate that the D-site reduces far faster than the Fe4S4 component, effectively eliminating this possibility. Rather, this component may alter catalytically important properties of the Ni center. The D-site is reduced through a pathway that probably does not involve the Fe4S4 component of this active-site cluster.

Unraveling the genetic basis of seed tocopherol content and composition in rapeseed (Brassica napus L.).

Science.gov (United States)

Wang, Xingxing; Zhang, Chunyu; Li, Lingjuan; Fritsche, Steffi; Endrigkeit, Jessica; Zhang, Wenying; Long, Yan; Jung, Christian; Meng, Jinling

2012-01-01

Tocopherols are important antioxidants in vegetable oils; when present as vitamin E, tocopherols are an essential nutrient for humans and livestock. Rapeseed (Brassica napus L, AACC, 2 n = 38) is one of the most important oil crops and a major source of tocopherols. Although the tocopherol biosynthetic pathway has been well elucidated in the model photosynthetic organisms Arabidopsis thaliana and Synechocystis sp. PCC6803, knowledge about the genetic basis of tocopherol biosynthesis in seeds of rapeseed is scant. This project was carried out to dissect the genetic basis of seed tocopherol content and composition in rapeseed through quantitative trait loci (QTL) detection, genome-wide association analysis, and homologous gene mapping. We used a segregating Tapidor × Ningyou7 doubled haploid (TNDH) population, its reconstructed F(2) (RC-F(2)) population, and a panel of 142 rapeseed accessions (association panel). Genetic effects mainly contributed to phenotypic variations in tocopherol content and composition; environmental effects were also identified. Thirty-three unique QTL were detected for tocopherol content and composition in TNDH and RC-F(2) populations. Of these, seven QTL co-localized with candidate sequences associated with tocopherol biosynthesis through in silico and linkage mapping. Several near-isogenic lines carrying introgressions from the parent with higher tocopherol content showed highly increased tocopherol content compared with the recurrent parent. Genome-wide association analysis was performed with 142 B. napus accessions. Sixty-one loci were significantly associated with tocopherol content and composition, 11 of which were localized within the confidence intervals of tocopherol QTL. This joint QTL, candidate gene, and association mapping study sheds light on the genetic basis of seed tocopherol biosynthesis in rapeseed. The sequences presented here may be used for marker-assisted selection of oilseed rape lines with superior tocopherol

Unraveling the genetic basis of seed tocopherol content and composition in rapeseed (Brassica napus L..

Directory of Open Access Journals (Sweden)

Xingxing Wang

Full Text Available BACKGROUND: Tocopherols are important antioxidants in vegetable oils; when present as vitamin E, tocopherols are an essential nutrient for humans and livestock. Rapeseed (Brassica napus L, AACC, 2 n = 38 is one of the most important oil crops and a major source of tocopherols. Although the tocopherol biosynthetic pathway has been well elucidated in the model photosynthetic organisms Arabidopsis thaliana and Synechocystis sp. PCC6803, knowledge about the genetic basis of tocopherol biosynthesis in seeds of rapeseed is scant. This project was carried out to dissect the genetic basis of seed tocopherol content and composition in rapeseed through quantitative trait loci (QTL detection, genome-wide association analysis, and homologous gene mapping. METHODOLOGY/PRINCIPAL FINDINGS: We used a segregating Tapidor × Ningyou7 doubled haploid (TNDH population, its reconstructed F(2 (RC-F(2 population, and a panel of 142 rapeseed accessions (association panel. Genetic effects mainly contributed to phenotypic variations in tocopherol content and composition; environmental effects were also identified. Thirty-three unique QTL were detected for tocopherol content and composition in TNDH and RC-F(2 populations. Of these, seven QTL co-localized with candidate sequences associated with tocopherol biosynthesis through in silico and linkage mapping. Several near-isogenic lines carrying introgressions from the parent with higher tocopherol content showed highly increased tocopherol content compared with the recurrent parent. Genome-wide association analysis was performed with 142 B. napus accessions. Sixty-one loci were significantly associated with tocopherol content and composition, 11 of which were localized within the confidence intervals of tocopherol QTL. CONCLUSIONS/SIGNIFICANCE: This joint QTL, candidate gene, and association mapping study sheds light on the genetic basis of seed tocopherol biosynthesis in rapeseed. The sequences presented here may be used

Impact of Phospholipids and Tocopherols on the Oxidative Stability of Soybean Oil-in-Water Emulsions.

Science.gov (United States)

Samdani, Gautam K; McClements, D Julian; Decker, Eric A

2018-04-18

Phospholipids have been shown to act synergistically with tocopherols and delay lipid oxidation in bulk oil. The synergistic activity between phospholipids and tocopherols is due to the ability of amino-group-containing phospholipids (e.g., phosphatidylethanolamine (PE) and phosphatidylserine (PS)) to convert oxidized tocopherol back into tocopherols. This study shows the effect of PE and PS on the antioxidant activity of different tocopherol homologues in oil-in-water emulsions. Effect of emulsifier type on the interaction between tocopherols and phospholipids was also studied. δ-Tocopherol and PE exhibited greater antioxidant activity as compared to α-tocopherol and PE. PS displayed 1.5-3 times greater synergism than PE with Tween 20 as emulsifier whereas both PE and PS had a similar antioxidant activity in the presence of α-tocopherol when bovine serum albumin was used as the emulsifier. This study is the first to show that PE and PS can act synergistically with tocopherols to inhibit lipid oxidation in oil-in-water emulsions and can present a new clean label antioxidant strategy for food emulsions.

Lipid oxidation in human low-density lipoprotein induced by metmyoglobin/H2O2

DEFF Research Database (Denmark)

Witting, P K; Willhite, C A; Davies, Michael Jonathan

1999-01-01

Metmyoglobin (metMb) and H(2)O(2) can oxidize low-density lipoprotein (LDL) in vitro, and oxidized LDL may be atherogenic. The role of alpha-tocopherol (alpha-TOH) in LDL oxidation by peroxidases such as metMb is unclear. Herein, we show that during metMb/H(2)O(2)-induced oxidation of native LDL...... of CE-O(O)H is dependent on, and correlates with, LDL's alpha-TOH content, yet does not require preformed lipid hydroperoxides or H(2)O(2). This indicates that in native LDL alpha-TOH can act as a phase-transfer agent and alpha-TO(*) as a chain-transfer agent propagating LDL lipid peroxidation via...

α-Tocopherol-5-Me-D synthesis, purification and characterization

International Nuclear Information System (INIS)

Corol-Cucu, Delia-Irina; Chiper, Diana; Mihaila, V.; Negoita, N.

2000-01-01

Vitamine E contains eight different compounds which have a ring with methyl and hydroxyl groups. Four of them, named tocopherols, contain a lateral saturated chain which derives from fitol and the others, named tocotrienols, have three double bounds in the lateral chain. The E vitamine is named 'vitamine of antisterility' because it is essential for good functioning of genital organs. It is involved in cellular oxidation processes, in muscle creatinine metabolism and metabolism of saccharides encouraging glycogen deposition in tissues. The labelling with deuterium of E vitamine is done in the following way: - The synthesis of α-tocopherol-5-Me-Cl from γ-tocopherol; - The replacement of chlorine with deuterium through catalytic dechlorination reaction. One obtains α-tocopherol-5-Me-D. The purification has been carried out through thin layer preparative chromatography, with C 6 H 6 as solvent (Al 2 O 3 as support) or solvent system C 6 H 6 :CH 3 OH (98:2, v/v) (silicagel as support). (authors)

Unexpected tolerance of alpha-cleavage of the prion protein to sequence variations.

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José B Oliveira-Martins

Full Text Available The cellular form of the prion protein, PrP(C, undergoes extensive proteolysis at the alpha site (109K [see text]H110. Expression of non-cleavable PrP(C mutants in transgenic mice correlates with neurotoxicity, suggesting that alpha-cleavage is important for PrP(C physiology. To gain insights into the mechanisms of alpha-cleavage, we generated a library of PrP(C mutants with mutations in the region neighbouring the alpha-cleavage site. The prevalence of C1, the carboxy adduct of alpha-cleavage, was determined for each mutant. In cell lines of disparate origin, C1 prevalence was unaffected by variations in charge and hydrophobicity of the region neighbouring the alpha-cleavage site, and by substitutions of the residues in the palindrome that flanks this site. Instead, alpha-cleavage was size-dependently impaired by deletions within the domain 106-119. Almost no cleavage was observed upon full deletion of this domain. These results suggest that alpha-cleavage is executed by an alpha-PrPase whose activity, despite surprisingly limited sequence specificity, is dependent on the size of the central region of PrP(C.

Quantification of minerals and tocopherols isomers in chestnuts approach chemometrics

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Nilson Evelazio de Souza

2014-10-01

Full Text Available The levels of the ?, ?, and (?+?-tocopherol isomers and the amounts of the minerals Se, Zn, Ca, Fe, K, Mn, Mg, and Cu were analyzed in chestnuts. High contents of Zn (>65% relative to the recommended dietary intake (RDI were found in all chestnuts except macadamia nuts (25% of the RDI. All samples had Se contents higher than the RDI: Brazil nuts > macadamia nuts, cashew nuts > pecans > almonds > pistachio nuts > hazelnuts > European nuts. A greater concentration of ?-tocopherol was found in almonds (30% of RDI. All samples, except for hazelnuts, almonds, and macadamia nuts, had (?+?- tocopherols, with the largest amount found in pistachios. Only pecan nuts and European nuts had ?-tocopherol and only in low amounts. Multivariate analysis allowed for better characterization and distinction of the chestnuts

A Comparison of Natural (D-α-tocopherol) and Synthetic (DL-α-tocopherol Acetate) Vitamin E Supplementation on the Growth Performance, Meat Quality and Oxidative Status of Broilers.

Science.gov (United States)

Cheng, K; Niu, Y; Zheng, X C; Zhang, H; Chen, Y P; Zhang, M; Huang, X X; Zhang, L L; Zhou, Y M; Wang, T

2016-05-01

The present study was conducted to compare the supplementation of natural (D-α-tocopherol) and synthetic (DL-α-tocopherol acetate) vitamin E on the growth performance, meat quality, muscular antioxidant capacity and genes expression related to oxidative status of broilers. A total of 144 1 day-old Arbor Acres broiler chicks were randomly allocated into 3 groups with 6 replicates of 8 birds each. Birds were given a basal diet (control group), and basal diet supplemented with either 20 IU D-α-tocopherol or DL-α-tocopherol acetate for 42 days, respectively. The results indicated that treatments did not alter growth performance of broilers (p>0.05). Compared with the control group, concentration of α-tocopherol in the breast muscle was increased by the supplementation of vitamin E (pnatural vitamin E group (pnatural vitamin E group (pnatural rather than synthetic vitamin E reduced MDA accumulation in the thigh (pnatural nor synthetic vitamin E supplementation altered muscular mRNA abundance of genes related to oxidative stress (p>0.05). It was concluded that vitamin E supplementation, especially the natural vitamin E, can enhance the retention of muscular α-tocopherol, improve meat quality and muscular antioxidant capacity of broilers.

On the diffusion of alpha-helical proteins in solvents

Science.gov (United States)

Barredo, Wilson I.; Bornales, Jinky B.; Bernido, Christopher C.; Aringa, Henry P.

2015-01-01

The winding probability function for a biopolymer diffusing in a crowded cell is obtained with the drift coefficient f(s) involving Bessel functions of general form f(s) = kJ2p+1 (νs). The variable s is the length along the chain and ν is a constant which can be used to simulate the frequency of appearance of a certain type of amino acid. Application of a particular case p = 3 to protein chains is carried out for different alpha helical proteins found in the Protein Data Bank (PDB). Analysis of our results leads us to an empirical formula that can be used to conveniently predict k/D and ν, where D is the diffusion coefficient of various α-helical proteins in solvents.

Regenerable antioxidants-introduction of chalcogen substituents into tocopherols.

Science.gov (United States)

Poon, Jia-Fei; Singh, Vijay P; Yan, Jiajie; Engman, Lars

2015-02-02

To improve the radical-trapping capacity of the natural antioxidants, alkylthio-, alkylseleno-, and alkyltelluro groups were introduced into all vacant aromatic positions in β-, γ- and δ-tocopherol. Reaction of the tocopherols with electrophilic chalcogen reagents generated by persulfate oxidation of dialkyl dichalcogenides provided convenient but low-yielding access to many sulfur and selenium derivatives, but failed in the case of tellurium. An approach based on lithiation of the appropriate bromo-tocopherol, insertion of chalcogen into the carbon-lithium bond, air-oxidation to a dichalcogenide, and final borohydride reduction/alkylation turned out to be generally applicable to the synthesis of all chalcogen derivatives. Whereas alkylthio- and alkylseleno analogues were generally poorer quenchers of lipid peroxyl radicals than the corresponding parents, all tellurium compounds showed a substantially improved radical-trapping activity. Introduction of alkyltelluro groups into the tocopherol scaffold also caused a dramatic increase in the regenerability of the antioxidant. In a two-phase lipid peroxidation system containing N-acetylcysteine as a water-soluble co-antioxidant the inhibition time was up to six-fold higher than that recorded for the natural antioxidants. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

A candidate gene-based association study of tocopherol content and composition in rapeseed (Brassica napus

Directory of Open Access Journals (Sweden)

Steffi eFritsche

2012-06-01

Full Text Available Rapeseed (Brassica napus L. is the most important oil crop of temperate climates. Rapeseed oil contains tocopherols, also known as vitamin E, which is an indispensable nutrient for humans and animals due to its antioxidant and radical scavenging abilities. Moreover, tocopherols are also important for the oxidative stability of vegetable oils. Therefore, seed oil with increased tocopherol content or altered tocopherol composition is a target for breeding. We investigated the role of nucleotide variations within candidate genes from the tocopherol biosynthesis pathway. Field trials were carried out with 229 accessions from a worldwide B. napus collection which was divided into two panels of 96 and 133 accessions. Seed tocopherol content and composition were measured by HPLC. High heritabilities were found for both traits, ranging from 0.62 to 0.94. We identified polymorphisms by sequencing selected regions of the tocopherol genes from the 96 accession panel. Subsequently, we determined the population structure (Q and relative kinship (K as detected by genotyping with genome-wide distributed SSR markers. Association studies were performed using two models, the structure-based GLM+Q and the PK mixed model. Between 26 and 12 polymorphisms within two genes (BnaX.VTE3.a, BnaA.PDS1.c were significantly associated with tocopherol traits. The SNPs explained up to 16.93 % of the genetic variance for tocopherol composition and up to 10.48 % for total tocopherol content. Based on the sequence information we designed CAPS markers for genotyping the 133 accessions from the 2nd panel. Significant associations with various tocopherol traits confirmed the results from the first experiment. We demonstrate that the polymorphisms within the tocopherol genes clearly impact tocopherol content and composition in B. napus seeds. We suggest that these nucleotide variations may be used as selectable markers for breeding rapeseed with enhanced tocopherol quality.

D-Glucosamine down-regulates HIF-1{alpha} through inhibition of protein translation in DU145 prostate cancer cells

Energy Technology Data Exchange (ETDEWEB)

Park, Jee-Young; Park, Jong-Wook; Suh, Seong-Il [Chronic Disease Research Center, School of Medicine, Keimyung University, 194 Dongsan-Dong, Jung-Gu, Daegu 700-712 (Korea, Republic of); Baek, Won-Ki, E-mail: wonki@dsmc.or.kr [Chronic Disease Research Center, School of Medicine, Keimyung University, 194 Dongsan-Dong, Jung-Gu, Daegu 700-712 (Korea, Republic of)

2009-04-24

D-Glucosamine has been reported to inhibit proliferation of cancer cells in culture and in vivo. In this study we report a novel response to D-glucosamine involving the translation regulation of hypoxia inducible factor (HIF)-1{alpha} expression. D-Glucosamine caused a decreased expression of HIF-1{alpha} under normoxic and hypoxic conditions without affecting HIF-1{alpha} mRNA expression in DU145 prostate cancer cells. D-Glucosamine inhibited HIF-1{alpha} accumulation induced by proteasome inhibitor MG132 and prolyl hydroxylase inhibitor DMOG suggesting D-glucosamine reduces HIF-1{alpha} protein expression through proteasome-independent pathway. Metabolic labeling assays indicated that D-glucosamine inhibits translation of HIF-1{alpha} protein. In addition, D-glucosamine inhibited HIF-1{alpha} expression induced by serum stimulation in parallel with inhibition of p70S6K suggesting D-glucosamine inhibits growth factor-induced HIF-1{alpha} expression, at least in part, through p70S6K inhibition. Taken together, these results suggest that D-glucosamine inhibits HIF-1{alpha} expression through inhibiting protein translation and provide new insight into a potential mechanism of the anticancer properties of D-glucosamine.

Effect of pentoxifylline and tocopherol on radiation proctitis/enteritis

International Nuclear Information System (INIS)

Hille, A.; Christiansen, H.; Pradier, O.; Hermann, R.M.; Siekmeyer, B.; Weiss, E.; Hess, C.F.; Schmidberger, H.; Hilgers, R.

2005-01-01

Background and purpose: Chronic radiation proctitis/enteritis is a relevant complication of pelvic irradiation, which is still mainly treated by supportive measures only. There is some evidence that the combined treatment with pentoxifylline and tocopherol might alter the pathogenesis of radiation-induced fibrosis. In a retrospective analysis the clinical benefit of the treatment with pentoxifylline/tocopherol on radiation-induced proctitis/enteritis was evaluated, compared to supportive care only. Patients and methods: Of 30 patients with radiation-induced proctitis/enteritis grade I-II according to the RTOG/EORTC toxicity criteria, 21 were treated with pentoxifylline and tocopherol. Depending on physician's decision nine patients received symptomatic treatment only. Results: With pentoxifylline/tocopherol treatment 15/21 patients (71%) experienced a relief of their symptoms. A reduction from grade I/II to grade 0 toxicity was observed in seven and from grade II to grade I toxicity in eight patients. No improvement was seen in six patients. The median time to improvement with pentoxifylline and tocopherol treatment was 28 weeks. In three of nine patients who were treated supportively only, deterioration of symptoms occurred. Three patients experienced no amelioration, and three patients with grade I toxicity experienced a spontaneous relief of their symptoms (33%). Conclusion: The combination treatment with pentoxifylline and tocopherol seems to have a benefit in patients with grade I-II radiation-induced proctitis/enteritis. The optimal schedule of treatment duration is not yet clear. From the observations made in this study it is assumed the treatment should be given for 6-12 months at least. A prospective phase II study should be undertaken to evaluate optimal treatment duration. (orig.)

Effect of pentoxifylline and tocopherol on radiation proctitis/enteritis

Energy Technology Data Exchange (ETDEWEB)

Hille, A.; Christiansen, H.; Pradier, O.; Hermann, R.M.; Siekmeyer, B.; Weiss, E.; Hess, C.F.; Schmidberger, H. [Goettingen Univ. (Germany). Dept. of Radiotherapy and Radiation; Hilgers, R. [Goettingen Univ. (Germany). Dept. for Medical Statisics

2005-09-15

Background and purpose: Chronic radiation proctitis/enteritis is a relevant complication of pelvic irradiation, which is still mainly treated by supportive measures only. There is some evidence that the combined treatment with pentoxifylline and tocopherol might alter the pathogenesis of radiation-induced fibrosis. In a retrospective analysis the clinical benefit of the treatment with pentoxifylline/tocopherol on radiation-induced proctitis/enteritis was evaluated, compared to supportive care only. Patients and methods: Of 30 patients with radiation-induced proctitis/enteritis grade I-II according to the RTOG/EORTC toxicity criteria, 21 were treated with pentoxifylline and tocopherol. Depending on physician's decision nine patients received symptomatic treatment only. Results: With pentoxifylline/tocopherol treatment 15/21 patients (71%) experienced a relief of their symptoms. A reduction from grade I/II to grade 0 toxicity was observed in seven and from grade II to grade I toxicity in eight patients. No improvement was seen in six patients. The median time to improvement with pentoxifylline and tocopherol treatment was 28 weeks. In three of nine patients who were treated supportively only, deterioration of symptoms occurred. Three patients experienced no amelioration, and three patients with grade I toxicity experienced a spontaneous relief of their symptoms (33%). Conclusion: The combination treatment with pentoxifylline and tocopherol seems to have a benefit in patients with grade I-II radiation-induced proctitis/enteritis. The optimal schedule of treatment duration is not yet clear. From the observations made in this study it is assumed the treatment should be given for 6-12 months at least. A prospective phase II study should be undertaken to evaluate optimal treatment duration. (orig.)

DNA-binding site of major regulatory protein alpha 4 specifically associated with promoter-regulatory domains of alpha genes of herpes simplex virus type 1.

OpenAIRE

Kristie, T M; Roizman, B

1986-01-01

Herpes simplex virus type 1 genes form at least five groups (alpha, beta 1, beta 2, gamma 1, and gamma 2) whose expression is coordinately regulated and sequentially ordered in a cascade fashion. Previous studies have shown that functional alpha 4 gene product is essential for the transition from alpha to beta protein synthesis and have suggested that alpha 4 gene expression is autoregulatory. We have previously reported that labeled DNA fragments containing promoter-regulatory domains of thr...

Rift Valley fever virus NSs protein promotes post-transcriptional downregulation of protein kinase PKR and inhibits eIF2alpha phosphorylation.

Science.gov (United States)

Ikegami, Tetsuro; Narayanan, Krishna; Won, Sungyong; Kamitani, Wataru; Peters, C J; Makino, Shinji

2009-02-01

Rift Valley fever virus (RVFV) (genus Phlebovirus, family Bunyaviridae) is a negative-stranded RNA virus with a tripartite genome. RVFV is transmitted by mosquitoes and causes fever and severe hemorrhagic illness among humans, and fever and high rates of abortions in livestock. A nonstructural RVFV NSs protein inhibits the transcription of host mRNAs, including interferon-beta mRNA, and is a major virulence factor. The present study explored a novel function of the RVFV NSs protein by testing the replication of RVFV lacking the NSs gene in the presence of actinomycin D (ActD) or alpha-amanitin, both of which served as a surrogate of the host mRNA synthesis suppression function of the NSs. In the presence of the host-transcriptional inhibitors, the replication of RVFV lacking the NSs protein, but not that carrying NSs, induced double-stranded RNA-dependent protein kinase (PKR)-mediated eukaryotic initiation factor (eIF)2alpha phosphorylation, leading to the suppression of host and viral protein translation. RVFV NSs promoted post-transcriptional downregulation of PKR early in the course of the infection and suppressed the phosphorylated eIF2alpha accumulation. These data suggested that a combination of RVFV replication and NSs-induced host transcriptional suppression induces PKR-mediated eIF2alpha phosphorylation, while the NSs facilitates efficient viral translation by downregulating PKR and inhibiting PKR-mediated eIF2alpha phosphorylation. Thus, the two distinct functions of the NSs, i.e., the suppression of host transcription, including that of type I interferon mRNAs, and the downregulation of PKR, work together to prevent host innate antiviral functions, allowing efficient replication and survival of RVFV in infected mammalian hosts.

Modification of survival and hematopoiesis in mice by tocopherol injection following irradiation

International Nuclear Information System (INIS)

Bichay, T.J.E.; Roy, R.M.

1986-01-01

The LD 50/30 of CD-1-female mice increased from 6.6 Gy to 7.0 Gy when 2.5 mg of dl-α-tocopherol was injected immediately post irradiation. Increased survival was associated with increased numbers of hematopoietic colony forming units (CFU). Endogeneous spleen colonies were found in greater numbers in the tocopherol-treated mice after irradiation. The vitamin, however, must be injected within five hours following irradiation to have this effect. The increased numbers of CFU in tocopherol-treated mice may be due to a stimulation of recovery of repair processes. Split-dose studies suggest that most repair of sublethal damage in hematopoietic stem cells take place within seven and nine hours following irradiation. Tocopherol injection appears to enhance the recovery manifested in the split-dose assay. There is also evidence that tocopherol-treatment caused an earlier onset of mitotic activity in CFU after irradiation. The increased number of spleen colonies in tocopherol-injected mice is not due to an altered CFU seeding efficiency associated with an altered spleen microenvironment. Tocopherol injection did not affect the shoulder of the stem cell survival curve using exogenous spleen colony assays of bone marrow-derived or spleen-derived hematopoietic stem cells. There appears to be a decrease in D 0 in the higher dose region (4.3 Gy) of the bone marrow exogenous SCA survival curves for the vehicle-injected and the non-injected groups; however, the tocopherol-injected group showed no evidence of change in radiosensitivity up to the highest dose used (5.0 Gy). Data may be interpreted to suggest that the therapeutic effect of tocopherol may involve repair of hematopoietic stem cell damage in the higher dose range of bone marrow syndrome. (orig.) [de

Functions of tocopherols in the cells of plants and other photosynthetic organisms.

Science.gov (United States)

Mokrosnop, V M

2014-01-01

Tocopherol synthesis has only been observed in photosynthetic organisms (plants, algae and some cyanobacteria). Tocopherol is synthesized in the inner membrane of chloroplasts and distributed between chloroplast membranes, thylakoids and plastoglobules. Physiological significance of tocopherols for human and animal is well-studied, but relatively little is known about their function in plant organisms. Among the best characterized functions oftocopherols in cells is their ability to scavenge and quench reactive oxygen species and fat-soluble by-products of oxidative stress. There are the data on the participation of different mechanisms of α-tocopherol action in protecting photosystem II (PS II) from photoinhibition both by deactivation of singlet oxygen produced by PSII and by reduction of proton permeability of thylakoid membranes, leading to acidification of lumen under high light conditions and activation of violaxanthin de-epoxidase. Additional biological activity of tocopherols, independent of its antioxidant functions have been demonstrated. Basic mechanisms for these effects are connected with the modulation of signal transduction pathways by specific tocopherols and, in some instances, by transcriptional activation of gene expression.

Activation of ethylene-responsive p-hydroxyphenylpyruvate dioxygenase leads to increased tocopherol levels during ripening in mango

Science.gov (United States)

Singh, Rajesh K.; Ali, Sharique A.; Nath, Pravendra; Sane, Vidhu A.

2011-01-01

Mango is characterized by high tocopherol and carotenoid content during ripening. From a cDNA screen of differentially expressing genes during mango ripening, a full-length p-hydroxyphenylpyruvate dioxygenase (MiHPPD) gene homologue was isolated that encodes a key enzyme in the biosynthesis of tocopherols. The gene encoded a 432-amino-acid protein. Transcript analysis during different stages of ripening revealed that the gene is ripening related and rapidly induced by ethylene. The increase in MiHPPD transcript accumulation was followed by an increase in tocopherol levels during ripening. The ripening-related increase in MiHPPD expression was also seen in response to abscisic acid and to alesser extent to indole-3-acetic acid. The expression of MiHPPD was not restricted to fruits but was also seen in other tissues such as leaves particularly during senescence. The strong ethylene induction of MiHPPD was also seen in young leaves indicating that ethylene induction of MiHPPD is tissue independent. Promoter analysis of MiHPPD gene in tomato discs and leaves of stable transgenic lines of Arabidopsis showed that the cis elements for ripening-related, ethylene-responsive, and senescence-related expression resided within the 1590 nt region upstream of the ATG codon. Functionality of the gene was demonstrated by the ability of the expressed protein in bacteria to convert p-hydroxyphenylpyruvate to homogentisate. These results provide the first evidence for HPPD expression during ripening of a climacteric fruit. PMID:21430290

Gastric clearance of alpha-1-antitrypsin under cimetidine perfusion. New test to detect protein-losing gastropathy

International Nuclear Information System (INIS)

Florent, C.; Vidon, N.; Flourie, B.; Carmantrand, A.; Zerbani, A.; Maurel, M.; Bernier, J.J.

1986-01-01

Gastric losses of plasma are usually measured with radiolabeled macromolecules. This method is expensive and cumbersome. Direct measurement of exudated plasma proteins are ineffective since proteins are denaturated by acidic gastric juice and pepsin. It was recently shown that albumin measurement after immediate neutralization allowed detection of gastric protein losses, but this method is quite complex and time consuming. We studied alpha 1-antitrypsin and 51Cr-labeled protein clearance in gastric juice during normal saline and cimetidine (1.5 mg/kg/hr) infusion in six healthy volunteers and six patients with exudative gastropathy. alpha 1-Antitrypsin was measurable in all samples during cimetidine infusion: alpha 1-AT and 51Cr losses were significantly correlated (P less than 0.001). The upper limit of gastric alpha 1-AT clearance in controls was 0.86 ml/hr (mean + 2 SD). Using this value, there was no overlapping between patients and controls. The upper limit of 51Cr test was 1.87 ml/hr (mean + 2 SD) in controls but gastric clearance of 51Cr was below this value in one patient. This suggests that the measurement of alpha 1-AT gastric clearance during cimetidine perfusion is a good test to detect an exudative gastropathy. This test is inexpensive and lasts only 3 hr

Ebselen: A thioredoxin reductase-dependent catalyst for α-tocopherol quinone reduction

International Nuclear Information System (INIS)

Fang Jianguo; Zhong Liangwei; Zhao Rong; Holmgren, Arne

2005-01-01

The thioredoxin system, composed of thioredoxin (Trx), thioredoxin reductase (TrxR), and NADPH, is a powerful protein disulfide reductase system with a broad substrate specificity. Recently the selenazol drug ebselen was shown to be a substrate for both mammalian TrxR and Trx. We examined if α-tocopherol quinone (TQ), a product of α-tocopherol oxidation, is reduced by ebselen in the presence of TrxR, since TQ was not a substrate for the enzyme itself. Ebselen reduction of TQ in the presence of TrxR was caused by ebselen selenol, generated from fast reduction of ebselen by the enzyme. TQ has no intrinsic antioxidant activity, while the product of reduction of TQ, α-tocopherolhydroquinone (TQH 2 ), is a potent antioxidant. The thioredoxin system dependence of ebselen to catalyze reduction of other oxidized species, such as hydrogen peroxide, dehydroascorbate, and peroxynitrite, is discussed. The ability of ebselen to reduce TQ via the thioredoxin system is a novel mechanism to explain the effects of the drug as an antioxidant in vivo

The T alpha 2 nuclear protein binding site from the human T cell receptor alpha enhancer functions as both a T cell-specific transcriptional activator and repressor

OpenAIRE

1990-01-01

T cell-specific expression of the human T cell receptor alpha (TCR- alpha) gene is regulated by the interaction of variable region promoter elements with a transcriptional enhancer that is located 4.5 kb 3' of the TCR-alpha constant region (C alpha) gene segment. The minimal TCR- alpha enhancer is composed of two nuclear protein binding sites, T alpha 1 and T alpha 2, that are both required for the T cell-specific activity of the enhancer. The T alpha 1 binding site contains a consensus cAMP ...

Syntheses of α and γ-tocopherols selectively labelled with deuterium

International Nuclear Information System (INIS)

Hughes, L.; Slaby, M.; Burton, G.W.; Ingold, K.U.

1990-01-01

Four deuterium-substituted α-tocopherols (dideutero-RRR, nonadeutero-ambo, nonadeutero-all-rac and undecadeutero-all-rac) and a dideutro-RRR-γ-tocopherol have been synthesized for use in studies of the biokinetics, bioavailability and metabolism of vitamin E. (author)

EFFECT OF α-TOCOPHEROL AND ASCORBIC ACIDS ON PERFORMANCE AND BLOOD IMMUNITY PROFILE OF MALE NATIVE MUSCOVY DUCK

Directory of Open Access Journals (Sweden)

E. Tugiyanti

2016-08-01

Full Text Available The purpose of the research was to assess the effect of α-tocopherol and ascobic acids on the performance and immunity blood profile of male native Muscovy duck. The materials used were 84 male Muscovy ducks at 9 weeks old. The research used completely randomized design with 7 treatments. The treatments were E0C0 : basal diet without α-tocopherol and ascobic acids, E400: basal diet+ α-tocopherol 400IU, E600: basal diet+α-tocopherol 600IU, C400: basal diet+ascorbic acid 400mg/kg, C600: basal diet+ascorbic acid 600mg/kg, E200C200: basal diet+α-tocopherol 200IU+ ascorbic acid 200mg/kg, and E300C300: basal diet+α-tocopherol 300IU+ ascorbic acid 300mg/kg. Each treatment was repeated 4 times and each replication consisted of 3 ducks. The observed variables were body weight, feed consumption, feed conversion ratio, packed cell volume (PCV, total of plasma protein (TPP, leucocyte count, basophil, heterophil, eosinophil, monocyte, lymphocytes count and heterophil/lymphocyte (H/L ratio of Muscovy duck. The result indicated that E0C0, E400, E600, C400, C600, E200C200 and E300C300 had no significant difference in body weight, feed intake and feed conversion. There were significant effects on PCV, leucocyte count, percentage of heterophil and lymphocytes, but had no significant effect on eosinophil, monocyte and the H/L ratio. The C400 resulted a higher PCV count, percentage of heterophil, and H/L ratio. The C 600 produced the highest leucocyte count. In conclusion, the supplementation of ascorbic acid at 400 - 600 mg/kg feed ascorbic acid could improve the immune profile, but could not improve the performance of Muscovy duck.

Inhibitory Effect of a γ-Tocopherol-Rich Mixture of Tocopherols on the Formation and Growth of LNCaP Prostate Tumors in Immunodeficient Mice

Energy Technology Data Exchange (ETDEWEB)

Zheng, Xi, E-mail: xizheng@rci.rutgers.edu [Susan Lehman Cullman Laboratory for Cancer Research, Department of Chemical Biology, Ernest Mario School of Pharmacy, Rutgers, The State University of New Jersey, 164 Frelinghuysen Road, Piscataway, NJ 08854 (United States); Cancer Institute of New Jersey, New Brunswick, NJ 08903 (United States); Cui, Xiao-Xing [Susan Lehman Cullman Laboratory for Cancer Research, Department of Chemical Biology, Ernest Mario School of Pharmacy, Rutgers, The State University of New Jersey, 164 Frelinghuysen Road, Piscataway, NJ 08854 (United States); Khor, Tin Oo; Huang, Ying [Department of Pharmaceutics, Ernest Mario School of Pharmacy, Rutgers, The State University of New Jersey, Piscataway, NJ 08854 (United States); DiPaola, Robert S; Goodin, Susan [Cancer Institute of New Jersey, New Brunswick, NJ 08903 (United States); Lee, Mao-Jung [Susan Lehman Cullman Laboratory for Cancer Research, Department of Chemical Biology, Ernest Mario School of Pharmacy, Rutgers, The State University of New Jersey, 164 Frelinghuysen Road, Piscataway, NJ 08854 (United States); Yang, Chung S [Susan Lehman Cullman Laboratory for Cancer Research, Department of Chemical Biology, Ernest Mario School of Pharmacy, Rutgers, The State University of New Jersey, 164 Frelinghuysen Road, Piscataway, NJ 08854 (United States); Cancer Institute of New Jersey, New Brunswick, NJ 08903 (United States); Kong, Ah-Ng [Cancer Institute of New Jersey, New Brunswick, NJ 08903 (United States); Department of Pharmaceutics, Ernest Mario School of Pharmacy, Rutgers, The State University of New Jersey, Piscataway, NJ 08854 (United States); Allan H, Conney [Susan Lehman Cullman Laboratory for Cancer Research, Department of Chemical Biology, Ernest Mario School of Pharmacy, Rutgers, The State University of New Jersey, 164 Frelinghuysen Road, Piscataway, NJ 08854 (United States); Cancer Institute of New Jersey, New Brunswick, NJ 08903 (United States)

2011-09-28

In the present study, we determined the effects of a γ-tocopherol-rich mixture of tocopherols (γ-TmT) on the growth and apoptosis of cultured human prostate cancer LNCaP cells. We also determined the effects of dietary γ-TmT on the formation and growth of LNCaP tumors in immunodeficient mice. In the in vitro study, we found that the activity of γ-TmT was stronger than α-tocopherol for inhibiting the growth and stimulating apoptosis in LNCaP cells. In the animal study, treatment of severe combined immunodeficient (SCID) mice with dietary γ-TmT inhibited the formation and growth of LNCaP xenograft tumors in a dose-dependent manner. Mechanistic studies showed that γ-TmT administration inhibited proliferation as reflected by decreased mitosis and stimulated apoptosis as reflected by increased caspase-3 (active form) expression in LNCaP tumors. In addition, dietary administration of γ-TmT increased the levels of α-, γ- and δ- tocopherol in plasma, and increased levels of γ- and δ- tocopherol were also observed in the prostate and in tumors. The present study demonstrated that γ-TmT had strong anticancer activity both in vitro and in vivo. Additional studies are needed to determine the potential preventive effect of γ-TmT for prostate cancer in humans.

Inhibitory Effect of a γ-Tocopherol-Rich Mixture of Tocopherols on the Formation and Growth of LNCaP Prostate Tumors in Immunodeficient Mice

International Nuclear Information System (INIS)

Zheng, Xi; Cui, Xiao-Xing; Khor, Tin Oo; Huang, Ying; DiPaola, Robert S; Goodin, Susan; Lee, Mao-Jung; Yang, Chung S; Kong, Ah-Ng; Allan H, Conney

2011-01-01

In the present study, we determined the effects of a γ-tocopherol-rich mixture of tocopherols (γ-TmT) on the growth and apoptosis of cultured human prostate cancer LNCaP cells. We also determined the effects of dietary γ-TmT on the formation and growth of LNCaP tumors in immunodeficient mice. In the in vitro study, we found that the activity of γ-TmT was stronger than α-tocopherol for inhibiting the growth and stimulating apoptosis in LNCaP cells. In the animal study, treatment of severe combined immunodeficient (SCID) mice with dietary γ-TmT inhibited the formation and growth of LNCaP xenograft tumors in a dose-dependent manner. Mechanistic studies showed that γ-TmT administration inhibited proliferation as reflected by decreased mitosis and stimulated apoptosis as reflected by increased caspase-3 (active form) expression in LNCaP tumors. In addition, dietary administration of γ-TmT increased the levels of α-, γ- and δ- tocopherol in plasma, and increased levels of γ- and δ- tocopherol were also observed in the prostate and in tumors. The present study demonstrated that γ-TmT had strong anticancer activity both in vitro and in vivo. Additional studies are needed to determine the potential preventive effect of γ-TmT for prostate cancer in humans

Deletion of Repeats in the Alpha C Protein Enhances the Pathogenicity of Group B Streptococci in Immune Mice

OpenAIRE

Gravekamp, C.; Rosner, Bernard; Madoff, L. C.

1998-01-01

The alpha C protein is a protective surface-associated antigen of group B streptococci (GBS). The prototype alpha C protein of GBS (strain A909) contains nine identical tandem repeats, each comprising 82 amino acids, flanked by N- and C-terminal domains. Clinical isolates of GBS show variable numbers of repeats with a normal distribution and a median of 9 to 10 repeats. Here, we show that escape mutants of GBS expressing one-repeat alpha C protein were 100-fold more pathogenic than GBS expres...

Use of alpha-tocopherol esters for topical vitamin E treatment: evaluation of their skin permeation and metabolism.

Science.gov (United States)

Ben-Shabat, Shimon; Kazdan, Yolia; Beit-Yannai, Elie; Sintov, Amnon C

2013-05-01

The aim of this work was to investigate new pro-vitamins based on α-tocopherol (α-Toc) and fatty acids, and to compare their properties with those of α-tocopherol acetate (α-TAc). Skin levels of α-Toc-fatty acid ester conjugates, total α-Toc and endogenous α-Toc were measured in skin samples taken from separate groups of treated and untreated rats. Multiple and extensive treatment with α-Toc oleate and α-TAc was also carried out to assess the skin accumulation and safety of these esters. The in-vivo studies revealed that α-Toc-fatty acid conjugates penetrated into the skin quantitatively while being comparable with the permeation of α-TAc. Differences were found between the levels of total α-Toc and endogenous α-Toc after application of α-TAc, α-Toc oleate, α-Toc linoleate, α-Toc-α linolenate and α-Toc palmitate, indicating that α-Toc conjugates of these fatty acids, but not α-Toc γ-linolenate or α-Toc stearate, were hydrolysed to free α-Toc. In long-term and extensive treatment, α-TAc was found to be lethal to rats treated with 1.15 mg/kg of this agent, which had been spread over 16 cm(2) of skin. Similar treatment with α-Toc oleate did not produce any side effects. This study suggests that α-Toc conjugates with unsaturated fatty acids may be a good alternative as stable vitamin E derivatives, rather than the α-TAc ester. © 2013 The Authors. JPP © 2013 Royal Pharmaceutical Society.

Redox-sensitive self-assembled nanoparticles based on alpha-tocopherol succinate-modified heparin for intracellular delivery of paclitaxel.

Science.gov (United States)

Yang, Xiaoye; Cai, Xiaoqing; Yu, Aihua; Xi, Yanwei; Zhai, Guangxi

2017-06-15

To remedy the problems riddled in cancer chemotherapy, such as poor solubility, low selectivity, and insufficient intra-cellular release of drugs, novel heparin-based redox-sensitive polymeric nanoparticles were developed. The amphiphilic polymer, heparin-alpha-tocopherol succinate (Hep-cys-TOS) was synthesized by grafting hydrophobic TOS to heparin using cystamine as the redox-sensitive linker, which could self-assemble into nanoparticles in phosphate buffer saline (PBS) with low critical aggregation concentration (CAC) values ranging from 0.026 to 0.093mg/mL. Paclitaxel (PTX)-loaded Hep-cys-TOS nanoparticles were prepared via a dialysis method, exhibiting a high drug-loading efficiency of 18.99%. Physicochemical properties of the optimized formulation were characterized by dynamic light scattering (DLS), transmission electron microscope (TEM) and differential scanning calorimetry (DSC). Subsequently, the redox-sensitivity of Hep-cys-TOS nanoparticles was confirmed by the changes in size distribution, morphology and appearance after dithiothreitol (DTT) treatment. Besides, the in vitro release of PTX from Hep-cys-TOS nanoparticles also exhibited a redox-triggered profile. Also, the uptake behavior and pathways of coumarin 6-loaded Hep-cys-TOS nanoparticles were investigated, suggesting the nanoparticles could be taken into MCF-7 cells in energy-dependent, caveolae-mediated and cholesterol-dependent endocytosis manners. Later, MTT assays of different PTX-free and PTX-loaded formulations revealed the desirable safety of PTX-free nanoparticles and the enhanced anti-cancer activity of PTX-loaded Hep-cys-TOS nanoparticles (IC 50 =0.79μg/mL). Apoptosis study indicated the redox-sensitive formulation could induce more apoptosis of MCF-7 cells than insensitive one (55.2% vs. 41.7%), showing the importance of intracellular burst release of PTX. Subsequently, the hemolytic toxicity confirmed the safety of the nanoparticles for intravenous administration. The results

Rift Valley fever virus NSs protein promotes post-transcriptional downregulation of protein kinase PKR and inhibits eIF2alpha phosphorylation.

Directory of Open Access Journals (Sweden)

Tetsuro Ikegami

2009-02-01

Full Text Available Rift Valley fever virus (RVFV (genus Phlebovirus, family Bunyaviridae is a negative-stranded RNA virus with a tripartite genome. RVFV is transmitted by mosquitoes and causes fever and severe hemorrhagic illness among humans, and fever and high rates of abortions in livestock. A nonstructural RVFV NSs protein inhibits the transcription of host mRNAs, including interferon-beta mRNA, and is a major virulence factor. The present study explored a novel function of the RVFV NSs protein by testing the replication of RVFV lacking the NSs gene in the presence of actinomycin D (ActD or alpha-amanitin, both of which served as a surrogate of the host mRNA synthesis suppression function of the NSs. In the presence of the host-transcriptional inhibitors, the replication of RVFV lacking the NSs protein, but not that carrying NSs, induced double-stranded RNA-dependent protein kinase (PKR-mediated eukaryotic initiation factor (eIF2alpha phosphorylation, leading to the suppression of host and viral protein translation. RVFV NSs promoted post-transcriptional downregulation of PKR early in the course of the infection and suppressed the phosphorylated eIF2alpha accumulation. These data suggested that a combination of RVFV replication and NSs-induced host transcriptional suppression induces PKR-mediated eIF2alpha phosphorylation, while the NSs facilitates efficient viral translation by downregulating PKR and inhibiting PKR-mediated eIF2alpha phosphorylation. Thus, the two distinct functions of the NSs, i.e., the suppression of host transcription, including that of type I interferon mRNAs, and the downregulation of PKR, work together to prevent host innate antiviral functions, allowing efficient replication and survival of RVFV in infected mammalian hosts.

Effect of tocopherol on atherosclerosis, vascular function, and inflammation in apolipoprotein E knockout mice with subtotal nephrectomy.

Science.gov (United States)

Shing, Cecilia M; Fassett, Robert G; Peake, Jonathan M; Coombes, Jeff S

2014-12-01

Inflammation and endothelial dysfunction contribute to cardiovascular disease, prevalent in chronic kidney disease (CKD). Antioxidant supplements such as tocopherols may reduce inflammation and atherosclerosis. This study aimed to investigate the effect of tocopherol supplementation on vascular function, aortic plaque formation, and inflammation in apolipoprotein E(-/-) mice with 5/6 nephrectomy as a model of combined cardiovascular and kidney disease. Nephrectomized mice were assigned to a normal chow diet group (normal chow), a group receiving 1000 mg/kg diet of α-tocopherol supplementation or a group receiving 1000 mg/kg diet mixed-tocopherol (60% γ-tocopherol). Following 12 weeks, in vitro aortic endothelial-independent relaxation was enhanced with both α-tocopherol and mixed-tocopherol (P tocopherol enhanced aortic contraction at noradrenaline concentrations of 3 × 10(-7) M to 3 × 10(-5) M (P tocopherol reduced systemic concentrations of IL-6 (P tocopherol also reduced MCP-1 (P tocopherol supplementation when compared to normal chow (P Tocopherol supplementation favorably influenced vascular function and cytokine profile, while it was also effective in reducing atherosclerosis in the apolipoprotein E(-/-) mouse with CKD. © 2014 John Wiley & Sons Ltd.

Increased haematopoietic stem cell survival in mice injected with tocopherol after X-irradiation

International Nuclear Information System (INIS)

Roy, R.M.; Malick, M.A.; Clark, G.M.

1982-01-01

Tocopherol injection (2.5 mg) immediately after irradiation reduced lethality only during bone-marrow syndrome. Endogenous spleen colony count at 8 days after X-radiation were significantly greater in vitamin-E-injected mice compared to noninjected or vehicle-injected animals; however, 59 Fe incorporation into spleen and bone marrow did not suggest enhanced erythropoietic activity in vitamin-E-injected groups at 2, 4, 8 and 10 days following irradiation. Mitotic index and frequency of micronuclei in marrow at 24 hours post irradiation (3 GY) were unaffected by tocopherol injection. The uptake of tritium from injected 3 H-tocopherol suggests that tocopherol has been accumulated in spleens but not marrows of irradiated animals within a few hours. Also tocopherol has no effect on endogenous spleen colony counts if injected after 5 hours nor is there an effect on the seeding efficiency of exogenous bonemarrow cells injected into recipients receiving tocopherol after irradiation. (orig.) [de

Study of transfer reactions ({alpha},t), ({alpha},{sup 3}He) in the f-p shell: mechanism and spectroscopic use; Etude des reactions de transfert ({alpha},t), ({alpha},{sup 3}He) dans la couche f-p mecanisme et utilisation spectroscopique

Energy Technology Data Exchange (ETDEWEB)

Roussel, P [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1968-05-01

We describe an experimental study of ({alpha},t), ({alpha},{sup 3}He) reactions at 44 MeV using a solid-state identifier, on the target-nuclei {sup 54}Fe and {sup 58,60,62,64}Ni. A critical study of optical model and of disturbed wave analysis has been performed. We show the complementarity of different transfer-reactions, the ambiguity of spectroscopic factors, the importance of the problem of the reaction mechanism. (author) [French] On decrit une etude experimentale des reactions ({alpha},t), ({alpha},{sup 3}He) a 44 MeV utilisant un systeme identificateur de particules sur les noyaux-cibles {sup 54}Fe et {sup 58,60,62,64}Ni. Une etude critique de modele optique et d'analyse en ondes deformees (D.W.B.A.) a ete entreprise. On montre la complementarite des differentes reactions de transfert, l'ambiguite des facteurs spectroscopiques, l'importance du probleme du mecanisme. (auteur)

An Insight into the Interactions between a-Tocopherol and Chitosan in Ultrasound-Prepared Nanoparticles

International Nuclear Information System (INIS)

Naghibzadeh, M.; Amani, A.; Esmaeilzadeh, E.; Amini, M.; Mottaghi-Dastjerdi, N.; Faramarzi, M.A.; Faramarzi, M.A.

2010-01-01

The aim of this study was to investigate the interactions between a-tocopherol and chitosan molecules prepared subsequent to preparation of a-tocopherol-loaded chitosan nanoparticles using ultrasonication. Dynamic light scattering (DLS) and scanning electron microscopy (SEM) analyses showed semi spherical particles with an average size of approximately 350 nm. Also from reconstitution test, a-tocopherol was suggested as stabilizing agent during lyophilization/reconstitution process. The zeta potentials of chitosan and a-tocopherol nanoparticles were larger than ±30 mV, representing suitable stability. Data obtained from FTIR showed possibility of chemical interaction between chitosan and a-tocopherol. Furthermore, the results from FTIR, NMR, and XRD spectroscopy confirmed electrostatic interactions between the two molecules. Overall, this procedure could be considered as a facile method to prepare a-tocopherol-loaded nanoparticles.

Den tilsatte mængde α-tocopherol til minkfoder kan reduceres

DEFF Research Database (Denmark)

Hymøller, Lone; Clausen, Tove N.; Clausen, Ditte

2016-01-01

Behovet for -Tocopherol (vitamin E) hos mink var tidligere vurderet til at være meget højt. Årsagen var minkfoderets høje indhold af letfordærvelige råvarer og indhold af fedt. Fedt harskner let, hvis det ikke opbevares under optimale temperatur- og iltmæssige forhold. -Tocopherol virker som...... transport af råvarer og færdigblandet foder. Dette gælder alle led af foderkæden såvel i foderindustri som på minkfarmene. Derfor er det rimeligt at genoverveje tidligere anbefalinger for -tocopherol i minkfoder med henblik på at vurdere behovet under moderne produktionsforhold og undgå en uøkonomisk...... overforsyning med -tocopherol. Forsøg gennemført i vækst- og pelsningssæsonen 2014 og 2015 med varierende tildeling af syntetisk og naturligt -tocopherol har vist, at de nuværende anbefalinger for -tocopheroltilsætning til minkfoder på 60 til 80 mg/kg foder kan reduceres til ca. 40 mg/kg foder, hvis der...

Effects of gamma radiation and menadione (vit. K3) on dissolution and dimerization of δ-tocopherol

International Nuclear Information System (INIS)

Kupczyk, B.; Gogolewski, M.

1997-01-01

Effect of ionizing radiation and menadione (vit. K 3 ) on dissolution and dimerization of δ-tocopherol was studied. Mixture of δ-tocopherol and menadione (vit. K 3 ) dissolved in benzene, ethanol or used in substantia were irradiated at 2.5, 5, 10, 20 kGy dose using Co-60 as a radiation source. Dissolution of δ-tocopherol in substantia was lower then disintegration of δ-tocopherol dissolved in benzene or in ethanol. However, we did not observe any significant difference between dissolution of δ-tocopherol in both studied solvents. The number of formed dimers of δ-tocopherol were different for all three cases tested. The quantities of δ-tocopherol dimers were dependent on radiation dose. (author)

Interaction of the heterotrimeric G protein alpha subunit SSG-1 of Sporothrix schenckii with proteins related to stress response and fungal pathogenicity using a yeast two-hybrid assay

Directory of Open Access Journals (Sweden)

González-Méndez Ricardo

2010-12-01

Full Text Available Abstract Background Important biological processes require selective and orderly protein-protein interactions at every level of the signalling cascades. G proteins are a family of heterotrimeric GTPases that effect eukaryotic signal transduction through the coupling of cell surface receptors to cytoplasmic effector proteins. They have been associated with growth and pathogenicity in many fungi through gene knock-out studies. In Sporothrix schenckii, a pathogenic, dimorphic fungus, we previously identified a pertussis sensitive G alpha subunit, SSG-1. In this work we inquire into its interactions with other proteins. Results Using the yeast two-hybrid technique, we identified protein-protein interactions between SSG-1 and other important cellular proteins. The interactions were corroborated using co-immuneprecipitation. Using these techniques we identified a Fe/Mn superoxide dismutase (SOD, a glyceraldehyde-3-P dehydrogenase (GAPDH and two ion transport proteins, a siderophore-iron transporter belonging to the Major Facilitator Superfamily (MFS and a divalent-cation transporter of the Nramp (natural resistance-associated macrophage protein family as interacting with SSG-1. The cDNA's encoding these proteins were sequenced and bioinformatic macromolecular sequence analyses were used for the correct classification and functional assignment. Conclusions This study constitutes the first report of the interaction of a fungal G alpha inhibitory subunit with SOD, GAPDH, and two metal ion transporters. The identification of such important proteins as partners of a G alpha subunit in this fungus suggests possible mechanisms through which this G protein can affect pathogenicity and survival under conditions of environmental stress or inside the human host. The two ion transporters identified in this work are the first to be reported in S. schenckii and the first time they are identified as interacting with fungal G protein alpha subunits. The association

Circulating tocopherols and risk of coronary artery disease: A systematic review and meta-analysis.

Science.gov (United States)

Li, Guangxiao; Li, Ying; Chen, Xin; Sun, Hao; Hou, Xiaowen; Shi, Jingpu

2016-05-01

Circulating level of tocopherols was supposed to be associated with risk of coronary artery disease. However, the results from previous studies remain controversial. Therefore, we conducted a meta-analysis based on observational studies to evaluate the association between circulating tocopherols and coronary artery disease risk for the first time. Meta-analysis. PubMed, Embase and Cochrane databases were searched to retrieve articles published during January 1995 and May 2015. Articles were included if they provided sufficient information to calculate the weighted mean difference and its corresponding 95% confidence interval. Circulating level of total tocopherols was significantly lower in coronary artery disease patients than that in controls (weighted mean difference -4.33 μmol/l, 95% confidence interval -6.74 to -1.91, P tocopherol alone was not significantly associated with coronary artery disease risk. Results from subgroup analyses showed that a lower level of circulating total tocopherols was merely associated with higher coronary artery disease risk in studies with higher sex ratio in cases (tocopherols was associated with early onset coronary artery disease rather than late onset coronary artery disease (tocopherols when the studies were stratified by matching status and assay methods. Our findings suggest that a deficiency in circulating total tocopherols might be associated with higher coronary artery disease risk. Whereas circulating α-tocopherol alone could not protect us from developing coronary artery disease. Further prospective studies were warranted to confirm our findings. © The European Society of Cardiology 2015.

Serum carotenoid, retinol and tocopherol concentrations and risk of cervical cancer among Chinese women.

Science.gov (United States)

Zhang, Yuan-Yuan; Lu, Ling; Abliz, Guzalnur; Mijit, Fatima

2015-01-01

Despite many epidemiological studies on the effects of dietary antioxidant micronutrients on risk of cervical cancer, the findings remain uncertain and little evidence is available for serum nutrient markers. The present study aimed to examine the relationship between serum carotenoid, retinol and tocopherol concentrations and risk of cervical cancer among Chinese women. We conducted a hospital-based case- control study in which 358 adults (158 incident cases and 200 controls) were recruited from Xinjiang, China. Serum levels of carotenoids (α-carotene, β-carotene, β-cryptoxanthin, lycopene and lutein/zeaxanthin), retinol, and tocopherols (α-tocopherol and γ-tocopherol) were assessed by reverse-phase high-performance liquid chromatography. We found inverse associations between serum carotenoid (α-carotene, β-carotene, and lutein/zeaxanthin) and tocopherol (α-tocopherol) concentrations and the risk of cervical cancer after adjusting for potential confounders, but a null association for retinol. The ORs for 1-SD increase were 0.71 (95% CI: 0.56- 0.92; p=0.003) for total carotenoids and 0.75 (95% CI: 0.60-0.94; p=0.008) for total tocopherols. These results show that higher serum concentrations of some carotenoids and tocopherols are associated with a lower risk of cervical cancer among Chinese women.

High-performance liquid chromatography for determination of α-tocopherol in vegetables

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Marcin Horbowicz

2013-12-01

Full Text Available A simple method for the determination of α-tocopherol in vegetables is described. The procedure consists of the following steps: saponification, extraction, silica-column clean-up, and high-performance liquid chromatography. Elution time for D, L-α-tocopherol was 9.0 min using a Zorbax Sil (250 x 4.6 mm column and an isocratic mobile phase of hexane-methanol (99.3 + 0.7, with a flow rate of 1 ml/min, and detection at 292 nm using a variable UV detector. The average recovery of α-tocopherol was 91.2%, and the minimum detectable amount was 0.1 mg/100 g of fresh vegetable tissue. This method is comparable to gas-chromatographic determination of α-tocopherol, but has fewer analytical steps and gives more reproducible results.

Nutritional composition of new peanut (Arachis hypogaea L.) cultivars

Energy Technology Data Exchange (ETDEWEB)

Campos-Mondragon, M. G.; Calderon de la Barca, A. M.; Duran-Prado, A.; Campos-Reyes, L. C.; Oliart-Ros, R. M.; Ortega-Garcia, J.; Medina-Juarez, L. A.; Angulo, O.

2009-07-01

Six peanut (Arachis hypogaea L.) cultivars (Col-24-Gro, Col-61-Gto, VA-81-B, Ranferi Diaz, NC-2 and Florunner) were studied for agricultural yield, chemical composition (protein, fat, carbohydrates, fiber and ash), amino acid profile, digestibility, fatty acid profile, tocopherol and sterol contents. Results indicated that Ranferi Diaz and Col-61-Gto presented the highest yield (6.3 Ton/ha). Protein content was from 23.5 to 26.6% and fat content ranged from 49.8-53.4%. Mean digestibility was 86%. Lysine and threonine levels in all cultivars were sufficient to meet human requirements. Total saturated fatty acids ranged from 15-18%. The oleic/linoleic ratio was estimated 1.3-1.4. Tocopherol levels varied from 390 to 706 ppm. The highest tocopherol levels corresponded to the cultivars with the lowest yield. The alpha tocopherol content was estimated at 90-150 ppm, while gamma tocopherol was 270-570 ppm. The main sterol present was A- sitosterol (approx. 65%). Ranferi Diaz variety presented the highest agronomic yield and the highest protein content but low oleic acid, low sterols and low total tocopherols. The differences among cultivars suggest differences in their applications. (Author) 40 refs.

Oxidation in fish oil-enriched mayonnaise 4 : Effect of tocopherol concentration on oxidative deterioration

DEFF Research Database (Denmark)

Jacobsen, Charlotte; Hartvigsen, Karsten; Lund, Pia

2001-01-01

The effect of the water-dispersible tocopherol preparation, Grindox 1032, and the oil-soluble tocopherol preparation, Toco 70, on oxidative stability in fish oil-enriched mayonnaise was examined. The two commercial antioxidant preparations were supplemented in different levels corresponding to 20......-280 ppm tocopherol in addition to the 600 ppm present in the oils used for the mayonnaise. The oxidative stability was assessed by sensory analysis, the tendency of formation of free radicals, and concentrations of lipid hydroperoxides and volatile oxidation products. The effect of tocopherol on oxidation...... depended on the nature and the concentration of the tocopherol preparation employed, and it also depended on the parameters evaluated. Addition of high levels of Grindox 1032 (similar to 140-280 ppm tocopherol) thus decreased the intensity of rancid off-flavor, but increased the formation of fishy off...

Enhanced tocopherol levels during early germination events in Chamaerops humilis var. humilis seeds.

Science.gov (United States)

Siles, Laura; Alegre, Leonor; Tijero, Verónica; Munné-Bosch, Sergi

2015-10-01

Most angiosperms accumulate vitamin E in the form of tocopherols in seeds, exerting a protective antioxidant role. However, several palm trees principally accumulate tocotrienols, rather than tocopherols, in seeds, as it occurs in other monocots. To unravel the protective role of either tocopherols or tocotrienols against lipid peroxidation during seed germination in Chamaerops humilis var. humilis; seed viability, natural and induced germination capacity, seed water content, malondialdehyde levels (as an indicator of the extent of lipid peroxidation) and vitamin E levels (including both tocopherols and tocotrienols) were examined at various germination phases in a simulated, natural seed bank. At the very early stages of germination (operculum removal), malondialdehyde levels increased 2.8-fold, to decrease later up to 74%, thus indicating a transient lipid peroxidation at early stages of germination. Tocopherol levels were absent in quiescent seeds and did not increase during operculum removal, but increased later presumably dampening malondialdehyde accumulation. Thereafter, tocopherols continued increasing, while lipid peroxidation levels decreased. By contrast, tocotrienols levels remained constant or even decreased as germination progressed, showing no correlation with lipid peroxidation levels. We hypothesize that despite their high tocotrienol content, seeds synthesize tocopherols during germination to protect lipids from peroxidation events. Copyright © 2015 Elsevier Ltd. All rights reserved.

δ- and γ-tocopherols, but not α-tocopherol, inhibit colon carcinogenesis in azoxymethane-treated F344 rats.

Science.gov (United States)

Guan, Fei; Li, Guangxun; Liu, Anna B; Lee, Mao-Jung; Yang, Zhihong; Chen, Yu-Kuo; Lin, Yong; Shih, Weichung; Yang, Chung S

2012-04-01

The cancer preventive activity of vitamin E has been extensively discussed, but the activities of specific forms of tocopherols have not received sufficient attention. Herein, we compared the activities of δ-tocopherol (δ-T), γ-T, and α-T in a colon carcinogenesis model. Male F344 rats, seven weeks old, were given two weekly subcutaneous injections of azoxymethane (AOM) each at a dose of 15 mg/kg body weight. Starting 1 week before the AOM injection, the animals were maintained on a modified AIN76A diet, or the same diet containing 0.2% of δ-T, γ-T, α-T, or a γ-T-rich mixture of tocopherols (γ-TmT), until the termination of the experiment at 8 weeks after the second AOM injection. δ-T treatment showed the strongest inhibitory effect, decreasing the numbers of aberrant crypt foci by 62%. γ-T and γ-TmT were also effective, but α-T was not. Immunohistochemical analysis showed that δ-T and γ-T treatments reduced the levels of 4-hydroxynonenal and nitrotyrosine and the expression of cyclin D1 in the colon, preserved the expression of PPAR-γ, and decreased the serum levels of prostaglandin E2 and 8-isoprostane. Supplementation with 0.2% δ-T, γ-T, or α-T increased the respective levels of tocopherols and their side-chain degradation metabolites in the serum and colon tissues. Rather high concentrations of δ-T and γ-T and their metabolites were found in colon tissues. Our study provides the first evidence for the much higher cancer preventive activity of δ-T and γ-T than α-T in a chemically induced colon carcinogenesis model. It further suggests that δ-T is more effective than γ-T. 2012 AACR

Modification of radiation-induced sex-linked recessive lethal mutation frequency by tocopherol

International Nuclear Information System (INIS)

Beckman, C.; Roy, R.M.; Sproule, A.

1982-01-01

The present study evaluates the effect of supplementing culture medium with α-tocopherol acetate on the yield of sex-linked recessive lethal mutants induced by X-irradiation in mature sperm of Drosophila. Although tocopherol treatment of males had no impact on the yield of mutations, a drastic reduction in mutation frequency was observed when irradiated males were mated to females raised and subsequently maintained on tocopherol-enriched diet. (orig./MG)

Determinants of RNA polymerase alpha subunit for interaction with beta, beta', and sigma subunits: hydroxyl-radical protein footprinting.

OpenAIRE

Heyduk, T; Heyduk, E; Severinov, K; Tang, H; Ebright, R H

1996-01-01

Escherichia coli RNA polymerase (RNAP) alpha subunit serves as the initiator for RNAP assembly, which proceeds according to the pathway 2 alpha-->alpha 2-->alpha 2 beta-->alpha 2 beta beta'-->alpha 2 beta beta' sigma. In this work, we have used hydroxyl-radical protein footprinting to define determinants of alpha for interaction with beta, beta', and sigma. Our results indicate that amino acids 30-75 of alpha are protected from hydroxyl-radical-mediated proteolysis upon interaction with beta ...

Effect of foliar application of α-tocopherol on vegetative growth and some biochemical constituents of two soybean genotypes under salt stress

Science.gov (United States)

Rahmawati, N.; Damanik, R. I. M.

2018-02-01

Foliar spray of plant growth regulating compounds including antioxidants is an effective strategy to overcome the adverse effects of environmental constraints on different plants. A field experiment was conducted on May - July 2017 at the experimental farm in Paluh Merbau Village Deli Serdang (EC 6 - 7 dS/m). The aim was to study the effects of foliar spray of α-tocopherol (0, 250, 500, 500 ppm) on vegetative growth and some chemical constituents of 2 soybean genotypes (Grobogan x Grobogan and Grobogan x Anjasmoro) under salt stress (EC 6 - 7 dS/m). Most of morphological and biochemical parameters were significantly affected by application of α-tocopherol. The α-tocopherol at 500 ppm recorded the best value of root fresh weight, shoot and root dry weight, number of leaves, chlorophyll b, and soluble protein content. There was significant difference found between plants treated with α-tocopherol in terms of number of branch, shoot fresh weight, and chlorophyll a. Soybean genotypes showed diverse morphology and physiological responses to salt stress. Grobogan x Anjasmoro genotype was salt-sensitive based on all variable, while Grobogan x Grobogan genotype was more tolerant based on morphological and biochemical characters.

Impact of α-, γ-, and δ-tocopherol on the radiation induced oxidation of rapeseed oil triacylglycerols

International Nuclear Information System (INIS)

Braunrath, Robert; Isnardy, Bettina; Solar, Sonja; Elmadfa, Ibrahim

2010-01-01

Gamma-irradiation (doses: 2, 4, 7, and 10 kGy) was used as oxidation tool to study the antioxidant effects of α-, γ-, and δ-tocopherol (enrichments 500-5000 ppm) in purified rapeseed oil triacylglycerols (RSOTG). Fatty acid composition, tocopherol degradation, primary (conjugated dienes (CD) and peroxide value (POV)) and secondary (p-anisidine value) oxidation products were chosen as test parameters. Fatty acid composition did not change. While secondary oxidation products could not be found in the irradiated samples, the POVs and CDs showed a significant, dose-dependent increase. α-Tocopherol did not inhibit the formation of peroxides, whereas γ- and δ-tocopherol reduced the POVs by more than 30%. No uniform effect of the different tocopherol concentrations at the particular doses could be established. The influence of the individual tocopherols on the CD formation was not pronounced. The degradation of the tocopherols decreased with increasing concentration. None of the tocopherols showed a prooxidant effect.

Synthesis and Theoretical Study of Molecularly Imprinted Nanospheres for Recognition of Tocopherols

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Chartchalerm Isarankura-Na-Ayudhya

2009-08-01

Full Text Available Molecular imprinting is a technology that facilitates the production of artificial receptors toward compounds of interest. The molecularly imprinted polymers act as artificial antibodies, artificial receptors, or artificial enzymes with the added benefit over their biological counterparts of being highly durable. In this study, we prepared molecularly imprinted polymers for the purpose of binding specifically to tocopherol (vitamin E and its derivative, tocopherol acetate. Binding of the imprinted polymers to the template was found to be two times greater than that of the control, non-imprinted polymers, when using only 10 mg of polymers. Optimization of the rebinding solvent indicated that ethanol-water at a molar ratio of 6:4 (v/v was the best solvent system as it enhanced the rebinding performance of the imprinted polymers toward both tocopherol and tocopherol acetate with a binding capacity of approximately 2 mg/g of polymer. Furthermore, imprinted nanospheres against tocopherol was successfully prepared by precipitation polymerization with ethanol-water at a molar ratio of 8:2 (v/v as the optimal rebinding solvent. Computer simulation was also performed to provide mechanistic insights on the binding mode of template-monomer complexes. Such polymers show high potential for industrial and medical applications, particularly for selective separation of tocopherol and derivatives.

alpha isoforms of soluble and membrane-linked folate-binding protein in human blood

DEFF Research Database (Denmark)

Hoier-Madsen, M.; Holm, J.; Hansen, S.I.

2008-01-01

supported the hypothesis that serum FBP (29 kDa) mainly originates from neutrophils. The presence of FBP/FR alpha isoforms were established for the first time in human blood using antibodies specifically directed against human milk FBP alpha. The alpha isoforms identified on erythrocyte membranes......, and in granulocytes and serum, only constituted an almost undetectable fraction of the functional FBP The FBP alpha in neutrophil granulocytes was identified as a cytoplasmic component by indirect immunofluorescence. Gel filtration of serum revealed a peak of FBP alpha (>120 kDa), which could represent receptor...... fragments from decomposed erythrocytes and granulocytes. The soluble FBPs may exert bacteriostatic effects and protect folates in plasma from biological degradation, whereas FRs on the surface of blood cells could be involved in intracellular folate uptake or serve as signal proteins. The latter receptors...

The tumor necrosis factor-alpha-induced protein 8 family in immune homeostasis and inflammatory cancer diseases.

Science.gov (United States)

Luan, Y Y; Yao, Y M; Sheng, Z Y

2013-01-01

Within the immune system homeostasis is maintained by a myriad of mechanisms that include the regulation of immune cell activation and programmed cell death. The breakdown of immune homeostasis may lead to fatal inflammatory diseases. We set out to identify genes of tumor necrosis factor-alpha-induced protein 8 (TNFAIP8) family that has a functional role in the process of immune homeostasis. Tumor necrosis factor-alpha-induced protein 8 (TNFAIP8), which functions as an oncogenic molecule, is also associated with enhanced cell survival and inhibition of apoptosis. Tumor necrosis factor-alpha-induced protein 8-like 2 (TIPE2) governs immune homeostasis in both the innate and adaptive immune system and prevents hyper-responsiveness by negatively regulating signaling via T cell receptors and Toll-like receptors (TLRs). There also exist two highly homologous but uncharacterized proteins, TIPE1 and TIPE3. This review is an attempt to provide a summary of TNFAIP8 family associated with immune homeostasis and inflammatory cancer diseases.

PGC-1{alpha} is required for AICAR induced expression of GLUT4 and mitochondrial proteins in mouse skeletal muscle

DEFF Research Database (Denmark)

Leick, Lotte; Fentz, Joachim; Biensø, Rasmus S

2010-01-01

We tested the hypothesis that repeated activation of AMPK induces mitochondrial and glucose membrane transporter gene/protein expression via a peroxisome proliferator activated receptor Upsilon co-activator (PGC)-1alpha dependent mechanism. Whole body PGC-1alpha knockout (KO) and littermate wild...... GLUT4, cytochrome c oxidase (COX)I and cytochrome (cyt) c protein expression ~10-40% relative to saline in white muscles of the WT mice, but not of the PGC-1alpha KO mice. In line, GLUT4 and cyt c mRNA content increased 30-60% 4h after a single AICAR injection relative to saline only in WT mice. One...... and PGC-1alpha KO mice. In conclusion, we here provide genetic evidence for a major role of PGC-1alpha in AMPK mediated regulation of mitochondrial and glucose membrane transport protein expression in skeletal muscle....

α-Tocopherol-5-Me-T. Synthesis, purification and characterization

International Nuclear Information System (INIS)

Corol-Cucu, Delia-Irina; Chiper, Diana; Mihaila, V.; Negoita, N.

2000-01-01

The E vitamine is named 'vitamine of antisterility' because it is essential for good functioning of genital organs. It is involved in cellular oxidation processes, in muscle creatinine metabolism and metabolism of saccharides encouraging glycogen deposition in tissues. The name of E vitamine is given to eight different compounds which have a ring with methyl and hydroxyl groups. Four of them, named tocopherols, contain a lateral saturated chain which derives from fitol and the others, named tocotrienols, have three double bonds in the lateral chain.This paper refers to synthesis, purification and characterization of α-tocopherol labelled with tritium in 5-methyl position. Tritium is different by the other hydrogen isotopes because it is the only radioactive isotope of hydrogen. The α-tocopherol-5-Me-T. The dry HCl is bubbled in a mixture of γ-tocopherol, paraformaldehyde and ZnCl 2 powder in dry Et 2 O. This solution remains at a standstill for a few hours and after that water is slowly added under stirring at low temperature ( 2 SO 4 . The next step is filtration and evaporation of ether stratum under nitrogen environment. One obtains 5-Cl-Me-α-tocopherol. For synthesis of α-tocopherol-5-Me-T the replacement of chlorine with tritium is done through catalytic dechlorination with Pd/C or Pd/CaCO 3 (10% Pd) as catalysts. One half of 5-Me-Cl compound is solved in dioxane and then the catalyst and deuterium are added under stirring, for 2 hours at room temperature. After filtration and washing with MeOH, the solvent is eliminated under vacuum conditions. Thus one obtains α-tocopherol-5-Me-T. The purification has been carried out through thin layer chromatography with C 6 H 6 as solvent (Al 2 O 3 as support) or solvent system C 6 H 6 : CH 3 OH (98:2, v/v) (silicagel as support). The determination of activity is carried out with LSC (Liquid Scintillation Counter). A 98% purity was determined through TLC in the same conditions while determination of activity

Localization of alpha-uterine protein in human endometrium.

Science.gov (United States)

Horne, C H; Paterson, W F; Sutcliffe, R G

1982-07-01

Immunoperoxidase staining was used to investigate the origin of human alpha-uterine protein (AUP). Specific staining was observed in the glandular epithelium of the endometrium during the secretory phase of the menstrual cycle and during pregnancy, and in a patient on an oestrogen-progestagen contraceptive pill. The pattern of staining strongly suggests that AUP is secreted into the uterine lumen. The location and concentration of AUP in the uterus may explain the relative concentrations of AUP in amniotic fluid and maternal serum.

The 21st century form of vitamin E--tocotrienol.

Science.gov (United States)

Bardhan, Jayeeta; Chakraborty, Runu; Raychaudhuri, Utpal

2011-01-01

Vitamin E family constitutes of tocopherol and tocotrienol. Each form has several isomers: alpha,beta, gamma, delta, desmo and didesmo. Although tocopherol is known much earlier, tocotrienol has been discovered more recently.Tocotrienol has higher antioxidant potential than tocopherol. Research shows that tocotrienol can inhibit the induced oxidative damage to lipids and proteins. Cholesterol biosynthesis pathway requires HMG Co A reductase. Tocotrienol degrades HMG Co A reductase protein and in turn lowers cholesterol synthesis. Tocotrienol can reverse ischemia-reperfusion which mediates cardiac dysfunction and induces c-Src protein expression. Tocotrienol prevents oxytosis and offers protection against Alzheimer's disease, Parkinson's disease, Hungtington's disease. Tocotrienol exerts anticancer property through cell cycle arrest, induction of apoptosis, inhibition of angiogenesis; antitumor activity. Tocotrienol also possesses anti-inflammatory, antidiabetic, antiadipogenic and antiatherogenic effect.

The role of the achiral template in enantioselective transformations. Radical conjugate additions to alpha-methacrylates followed by hydrogen atom transfer.

Science.gov (United States)

Sibi, Mukund P; Sausker, Justin B

2002-02-13

We have evaluated various achiral templates (1a-g, 10, and 16) in conjunction with chiral Lewis acids in the conjugate addition of nucleophilic radicals to alpha-methacrylates followed by enantioselective H-atom transfer. Of these, a novel naphthosultam template (10) gave high enantioselectivity in the H-atom-transfer reactions with ee's up to 90%. A chiral Lewis acid derived from MgBr(2) and bisoxazoline (2) gave the highest selectivity in the enantioselective hydrogen-atom-transfer reactions. Non-C(2) symmetric oxazolines (20-25) have also been examined as ligands, and of these, compound 25 gave optimal results (87% yield and 80% ee). Insights into rotamer control in alpha-substituted acrylates and the critical role of the tetrahedral sulfone moiety in realizing high selectivity are discussed.

Structure based protein engineering of Bacillus stearothermophilus {alpha}-amylase: toward a new substrate specificity

Energy Technology Data Exchange (ETDEWEB)

Rasera, Ana Claudia [Sao Paulo Univ., SP (Brazil). Inst. de Ciencias Biomedicas; Iulek, Jorge [Universidade Estadual de Ponta Grossa, PR (Brazil). Inst. de Quimica; Delboni, Luis Fernando; Barbosa, Valma Martins Barbosa [Parana Univ., Curitiba, PR (Brazil). Dept. de Bioquimica

1997-12-31

Full text. Structural similarity is observed in all members of {alpha}-amylase family but different products are generated during hydrolysis of starch due to different affinities for intermediate dextrins. In order to understand the structural determinants for this property and to introduce different specificity to {alpha}-amylase of Bacillus stearothermophilus we intend to solve the three dimensional structure by X-ray crystallography of the native protein by using synchrotron radiation at Brazilian National Synchrotron Light Laboratory (LNLS). Protein was over expressed in E. coli, purified and crystallization experiments were carried out by using sparse matrix Crystal Screen and Crystal Screen II from Hampton Research (Laguna Hills, CA, USA). Several condition have produced crystals with some defined characteristic: MDP seems to be important to the crystallization: the preferential pH is around 7.5 with organic buffer (HEPES); organic solvent as 2-propanol seems to be also important for the crystallization. On those condition crystals appeared as cluster of needles or small crystals with high number of nucleation. New conditions are being prepared to improve the site and quality of crystals. Data collection of native of Bacillus stearothermophilus {alpha}-amylase will e done at Protein Crystallography Station at LNLS. Crystal structure of mutated {alpha}-amylase bu site direct mutagenesis of residues suggested by the native crystal structure will be obtained. Co-crystallization of Bacillus stearothermophilus {alpha}-amylase and oligosaccharide will be carried out to identify residues involved in the binding site to plan new mutation. In another series of mutation the putative binding site residues, once identified, will be mutated to residues observed in TAKA amylase to confer different specificity to {alpha}-amylase. Based on the available TAKA amylase structure, in the primary sequence homology and in the three dimensional model of Bacillus stearothermophilus

Receptor tyrosine phosphatase R-PTP-alpha is tyrosine-phosphorylated and associated with the adaptor protein Grb2

DEFF Research Database (Denmark)

Su, J; Batzer, A; Sap, J

1994-01-01

Receptor tyrosine phosphatases (R-PTPases) have generated interest because of their suspected involvement in cellular signal transduction. The adaptor protein Grb2 has been implicated in coupling receptor tyrosine kinases to Ras. We report that a ubiquitous R-PTPase, R-PTP-alpha, is tyrosine......-phosphorylated and associated in vivo with the Grb2 protein. This association can be reproduced in stably and transiently transfected cells, as well as in vitro using recombinant Grb2 protein. Association requires the presence of an intact SH2 domain in Grb2, as well as tyrosine phosphorylation of R-PTP-alpha. This observation...... links a receptor tyrosine phosphatase with a key component of a central cellular signalling pathway and provides a basis for addressing R-PTP-alpha function....

Antioxidant effect of mono- and dihydroxyphenols in sunflower oil with different levels of naturally present tocopherols

Science.gov (United States)

Hrádková, Iveta; Merkl, Roman; Šmidrkal, Jan; Kyselka, Jan; Filip, Vladimír

2013-01-01

Antioxidant properties of mono- and dihydroxyphenolic acids and their alkyl esters were examined, with emphasis on the relationship between their molecular structure and antioxidant activity. Test media with different tocopherol level were used for determining the oxidative stability: original refined sunflower oil (total tocopherols 149.0 mg/kg), partially tocopherol-stripped sunflower oil (total tocopherols 8.7 mg/kg) and distilled fatty acid methyl esters (FAME) as a tocopherol-free medium. The chemical reaction of tocopherols with diazomethane tested for the purpose to eliminate their antioxidant activity failed due to the negligible degree of methylation of hydroxyl group in the tocopherol molecule. Caffeic acid and protocatechuic acid (3,4-dihydroxyphenolic acids) and their alkyl esters were found to be more active antioxidants than monohydroxyphenolic acid (p-hydroxybenzoic acid), 2,5-dihydroxyphenolic acid (gentisic acid), 3-methoxy-4-hydroxyphenolic acids (vanillic and ferulic acids) and their corresponding alkyl esters. Naturally present tocopherols in refined sunflower oil proved to have a synergistic effect on gentisic acid but not on its alkyl esters. In contrast, tocopherols showed an antagonistic effect on alkyl esters of caffeic acid, because their protection factors decreased with increasing level of tocopherols in the test medium. Moreover, the antioxidant activity of these alkyl esters decreased with increasing length of their alkyl chain in conformity with the polar paradox hypothesis. Practical applications: Tocopherols as naturally present antioxidants influence considerably the antioxidant activity of other antioxidants added to plant oils used as a test medium. Distilled fatty acid methyl esters prepared from refined sunflower oil may serve as an optimal tocopherol-free test medium. Some alkyl esters of phenolic acids were evaluated to be applicable as natural more lipophilic antioxidants in comparison with phenolic acids. PMID:23997655

Supramolecular Architectures and Mimics of Complex Natural Folds Derived from Rationally Designed alpha-Helical Protein Structures

Science.gov (United States)

Tavenor, Nathan Albert

Protein-based supramolecular polymers (SMPs) are a class of biomaterials which draw inspiration from and expand upon the many examples of complex protein quaternary structures observed in nature: collagen, microtubules, viral capsids, etc. Designing synthetic supramolecular protein scaffolds both increases our understanding of natural superstructures and allows for the creation of novel materials. Similar to small-molecule SMPs, protein-based SMPs form due to self-assembly driven by intermolecular interactions between monomers, and monomer structure determines the properties of the overall material. Using protein-based monomers takes advantage of the self-assembly and highly specific molecular recognition properties encodable in polypeptide sequences to rationally design SMP architectures. The central hypothesis underlying our work is that alpha-helical coiled coils, a well-studied protein quaternary folding motif, are well-suited to SMP design through the addition of synthetic linkers at solvent-exposed sites. Through small changes in the structures of the cross-links and/or peptide sequence, we have been able to control both the nanoscale organization and the macroscopic properties of the SMPs. Changes to the linker and hydrophobic core of the peptide can be used to control polymer rigidity, stability, and dimensionality. The gaps in knowledge that this thesis sought to fill on this project were 1) the relationship between the molecular structure of the cross-linked polypeptides and the macroscopic properties of the SMPs and 2) a means of creating materials exhibiting multi-dimensional net or framework topologies. Separate from the above efforts on supramolecular architectures was work on improving backbone modification strategies for an alpha-helix in the context of a complex protein tertiary fold. Earlier work in our lab had successfully incorporated unnatural building blocks into every major secondary structure (beta-sheet, alpha-helix, loops and beta

Coevolving residues of (beta/alpha)(8)-barrel proteins play roles in stabilizing active site architecture and coordinating protein dynamics.

Science.gov (United States)

Shen, Hongbo; Xu, Feng; Hu, Hairong; Wang, Feifei; Wu, Qi; Huang, Qiang; Wang, Honghai

2008-12-01

Indole-3-glycerol phosphate synthase (IGPS) is a representative of (beta/alpha)(8)-barrel proteins-the most common enzyme fold in nature. To better understand how the constituent amino-acids work together to define the structure and to facilitate the function, we investigated the evolutionary and dynamical coupling of IGPS residues by combining statistical coupling analysis (SCA) and molecular dynamics (MD) simulations. The coevolving residues identified by the SCA were found to form a network which encloses the active site completely. The MD simulations showed that these coevolving residues are involved in the correlated and anti-correlated motions. The correlated residues are within van der Waals contact and appear to maintain the active site architecture; the anti-correlated residues are mainly distributed on opposite sides of the catalytic cavity and coordinate the motions likely required for the substrate entry and product release. Our findings might have broad implications for proteins with the highly conserved (betaalpha)(8)-barrel in assessing the roles of amino-acids that are moderately conserved and not directly involved in the active site of the (beta/alpha)(8)-barrel. The results of this study could also provide useful information for further exploring the specific residue motions for the catalysis and protein design based on the (beta/alpha)(8)-barrel scaffold.

A correlation between tocopherol content and antioxidant activity in seeds and germinating seeds of soybean cultivars.

Science.gov (United States)

Lee, Yu Young; Park, Hyang Mi; Hwang, Tae Young; Kim, Sun Lim; Kim, Mi Jung; Lee, Seuk Ki; Seo, Min Jung; Kim, Kee Jong; Kwon, Young-Up; Lee, Sang Chul; Kim, Yul Ho

2015-03-15

Tocopherols are crucial lipid-soluble antioxidants and essential nutrients. There is increasing interest in the biofortification of crops with vitamin E for reducing micronutrient malnutrition. However, relatively little is known about the development of soybean cultivars with high levels of tocopherol through combined breeding. Tocopherol contents of seeds and germinating seeds of 28 Korean soybean cultivars were analyzed and evaluated for health-promoting activities. Total tocopherol concentrations ranged from 203.9 to 503.1 µg g⁻¹ in seeds and from 20.1 to 230.1 µg g⁻¹ in germinating seeds. The traditional landraces of HaNagari (HN, 503.1 µg g⁻¹), Orialtae (OL, 486.6 µg g⁻¹), SuMoktae (SM, 476.5 µg g⁻¹) and SoRitae (SR, 475.5 µg g⁻¹) showed high levels of tocopherol content. The contents of the four isomers of tocopherol in seeds and germinating seeds were correlated with lipid peroxidation. The γ- and δ-tocopherol contents in seeds were related to 1,1-diphenyl-2-picrylhydrazyl free radical scavenging activity (0.434; P tocopherol content was higher in soybean landraces as compared with modern cultivars developed by cross-breeding. These results suggest that soybean breeding is necessary to increase tocopherol levels. © 2014 Society of Chemical Industry.

[(35)S]-GTPgammaS autoradiography reveals alpha(2) adrenoceptor-mediated G-protein activation in amygdala and lateral septum.

Science.gov (United States)

Newman-Tancredi, A; Chaput, C; Touzard, M; Millan, M J

2000-04-03

alpha(2)-adrenoceptor-mediated G-protein activation was examined by [(35)S]-GTPgammaS autoradiography. In alpha(2)-adrenoceptor-rich regions (amygdala, lateral septum), noradrenaline stimulated [(35)S]-GTPgammaS binding. These actions were abolished by the selective alpha(2) antagonist, atipamezole. Conversely, in caudate nucleus, which expresses few alpha(2) receptors, noradrenaline-induced stimulation was not inhibited by atipamezole, suggesting that it is not mediated by alpha(2)-adrenoceptors.