Circulating interleukin-6 is not altered while γ-tocopherol is increased in subjects scheduled for knee surgery with low vitamin D.

Barker T, Henriksen VT, Rogers VE, Momberger NG, Rasmussen GL, Trawick RH.

Cytokine. 2016 Dec;88:108-114. doi: 10.1016/j.cyto.2016.08.025. Epub 2016 Sep 1.

Abstract

The purpose of this study was to identify if circulating interleukin (IL)-6 and γ-tocopherol (γT) fluctuate with vitamin D status in subjects with an underlying knee joint injury or disease. We hypothesized that low vitamin D associates with an increase in plasma γT while serum IL-6 remains unchanged in subjects with an underlying knee joint trauma or disease. Fifty-four subjects scheduled to undergo primary, unilateral anterior cruciate ligament reconstructive surgery (ACL; n=27) or total knee arthroplasty (TKA; n=27) were studied. Circulating γT, α-tocopherol (αT), lipids (cholesterol and triglycerides), IL-6, and 25-hydroxyvitamin D (25(OH)D) were measured in fasting blood samples obtained prior to surgery. Subjects were classified as vitamin D deficient, insufficient, or sufficient if they had a serum 25(OH)D concentration <50, 50-75, or >75nM, respectively. The majority (57%) of the subjects possessed a serum 25(OH)D less than 50nM. Circulating cholesterol, triglycerides, and IL-6 were not significantly (all p>0.05) different between vitamin D status groups. However, lipid corrected αT was significantly (p<0.05) decreased and both lipid- and non-lipid-corrected plasma γT concentrations were significantly (both p<0.05) increased with low serum 25(OH)D (i.e., <50nM). A significant (p<0.05) multi-variate analysis revealed that an increase in plasma γT per lipids was significantly (p<0.05) predicted by a decrease in serum 25(OH)D but not by a decrease in plasma αT per lipids. We conclude that low vitamin D associates with an increase in plasma γT but not IL-6 in subjects with an underlying joint injury or disease.

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Vitamin E induces regular structure and stability of human insulin, more intense than vitamin D3.

Soleymani H, Saboury AA, Moosavi-Movahedi AA, Rahmani F, Maleki J, Yousefinejad S, Maghami P.

Int J Biol Macromol. 2016 Dec;93(Pt A):868-878. doi: 10.1016/j.ijbiomac.2016.09.047.

Abstract

Changes in human environment and lifestyle over the last century have caused a dramatic increase in the occurrence of diabetes. Research of past decades illustrated that vitamin D and E have a key role in the improvement of diabetes by reducing oxidative stress, protein glycosylation, insulin resistance and also improving beta cell function. Binding properties and conformational changes of human insulin upon interaction with vitamins D3 and E (α-tocopherol) were investigated by spectroscopy, differential scanning calorimetry (DSC) and molecular dynamic simulation. Tyrosine fluorescence quenching studies indicates changes in the human insulin conformation in the presence of vitamins. Binding constants of vitamins D3 and E for human insulin were determined to be 2.7 and 1.5 (×10-5M-1) and the corresponding average numbers of binding sites were determined to be 1.3 and 1.2, respectively. Far- and near-UV circular dichroism studies showed that vitamin E can significantly change the secondary and tertiary structures of human insulin via an increase in the content of α-helix structure. Results of DSC showed that both vitamins D3 and E stabilize the structure of human insulin. Molecular dynamic simulation results indicated that vitamin D3 decreases the helical and strand structural contents of human insulin, but vitamin E stabilizes more regular secondary structures such as helical and strand structural contents as shown by experimental results.

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Ginkgo biloba leaf extract and alpha-tocopherol attenuate haloperidol-induced orofacial dyskinesia in rats: Possible implication of antiapoptotic mechanisms by preventing Bcl-2 decrease and Bax elevation.

An HM, Tan YL, Shi J, Wang Z, Lv MH, Soares JC, Zhou D, Yang F, Zhang XY.

Phytomedicine. 2016 Dec 1;23(13):1653-1660. doi: 10.1016/j.phymed.2016.10.009. Epub 2016 Oct 15.

Abstract

Tardive dyskinesia (TD) is a serious side effect of long-term administration of typical neuroleptics, such as haloperidol. The pathophysiology of TD remains unclear, but the experimental evidence suggests that free radical-induced neuronal apoptosis in the basal ganglia may play an important role. This study was to investigate changes in Bax and Bcl-2 expression levels in TD-associated brain regions and the effects of the antioxidant EGb761 on Bax and Bcl-2 levels in an animal model of TD. The results obtained demonstrate that long-term haloperidol administration may affect Bcl-2 protein family expression and promote neuronal apoptosis in the basal ganglia. In combination with their antioxidant capacity, EGb761 and alpha-tocopherol‘s antiapoptotic effects through Bcl-2 might account for the symptom improvement observed in haloperidol-induced TD rats.

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A Randomized Controlled Clinical Trial Investigating the Effects of Omega-3 Fatty Acids and Vitamin E Co-Supplementation on Biomarkers of Oxidative Stress, Inflammation and Pregnancy Outcomes in Gestational Diabetes.

Jamilian M, Hashemi Dizaji S, Bahmani F, Taghizadeh M, Memarzadeh MR, Karamali M, Akbari M, Asemi Z.

Can J Diabetes. 2016 Nov 21. pii: S1499-2671(16)30266-0. doi: 10.1016/j.jcjd.2016.09.004. [Epub ahead of print]

Abstract

Limited data are available for assessing the effects of omega-3 fatty acids and vitamin E co-supplementation on metabolic profiles and pregnancy outcomes in gestational diabetes (GDM). This study was designed to determine the effects of omega-3 fatty acids and vitamin E co-supplementation on biomarkers of oxidative stress, inflammation and pregnancy outcomes in women with GDM.

This randomized, double-blind, placebo-controlled clinical trial was conducted in 60 patients with GDM who were not taking oral hypoglycemic agents. Patients were randomly allocated to intake either 1000 mg omega-3 fatty acids from flaxseed oil plus 400 IU vitamin E supplements (n=30) or placebo (n=30) for 6 weeks. Fasting blood samples were obtained from the women at the beginning of the study and after the 6-week intervention to quantify related markers.

After 6 weeks of intervention, omega-3 fatty acids and vitamin E co-supplementation, compared with the placebo, resulted in a significant rise in total antioxidant capacity (TAC) (+187.5±224.9 vs. -32.5±136.1 mmol/L; p<0.001); nitric oxide (NO) (+5.0±7.7 vs. -12.0±28.0 µmol/L; p=0.002) and a significant decrease in plasma malondialdehyde (MDA) concentrations (-0.1±0.9 vs. +0.6±1.4 µmol/L; p=0.03). Co-supplementation with omega-3 fatty acids and vitamin E showed no detectable changes in plasma glutathione and serum high-sensitivity C-reactive protein levels. Joint omega-3 fatty acids and vitamin E supplementation resulted in lower incidences of hyperbilirubinemia in newborns (10.3% vs. 33.3%; p=0.03).

Overall, omega-3 fatty acids and vitamin E co-supplementation for 6 weeks in women with GDM had beneficial effects on plasma TAC, MDA and NO and on the incidence of the newborns’ hyperbilirubinemia.

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Role of Endogenous and Exogenous Tocopherols in the Lipid Stability of Marine Oil Systems: A Review.

Suárez-Jiménez GM, López-Saiz CM, Ramírez-Guerra HE, Ezquerra-Brauer JM, Ruiz-Cruz S, Torres-Arreola W.

Int J Mol Sci. 2016 Nov 24;17(12). pii: E1968.

Abstract

In marine organisms primarily intended for human consumption, the quality of the muscle and the extracted oils may be affected by lipid oxidation during storage, even at low temperatures. This has led to a search for alternatives to maintain quality. In this sense, antioxidant compounds have been used to prevent such lipid deterioration. Among the most used compounds are tocopherols, which, due to their natural origin, have become an excellent alternative to prevent or retard lipid oxidation and maintain the quality of marine products. Tocopherols as antioxidants have been studied both exogenously and endogenously. Exogenous tocopherols are often used by incorporating them into plastic packaging films or adding them directly to fish oil. It has been observed that exogenous tocopherols incorporated in low concentrations maintain the quality of both muscle and the extracted oils during food storage. However, it has been reported that tocopherols applied at higher concentrations act as a prooxidant molecule, probably because their reactions with singlet oxygen may generate free radicals and cause the oxidation of polyunsaturated fatty acids in fish oils. However, when tocopherols are included in a fish diet (endogenous tocopherols), the antioxidant effect on the muscle lipids is more effective due to their incorporation into the membrane lipids, which can help extend the shelf life of seafood by reducing the lipid deterioration that occurs due to antioxidant synergy with other phenolic compounds used supplements in fish muscle. This review focuses on the most important studies in this field and highlights the potential of using tocopherols as antioxidants in marine oils.

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Nasal mucosa healing after endoscopic sinus surgery in chronic rhinosinusitis of elderly patients: role of topic alpha-tocopherol acetate.

Testa D, Marcuccio G, Panin G, Bianco A, Tafuri D, Thyrion FZ, Nunziata M, Piombino P, Guerra G, Motta G.

Aging Clin Exp Res. 2016 Nov 25. [Epub ahead of print]

Abstract

Chronic rhinosinusitis (CRS) in European country ranges in elderly patients from 4.5 to 12% of population and has a significant effect on quality of life. In these patients, rhinosinusitis is linked to immune functions changes with age and to mucosal paraphysiological alterations such as crusting formations with atrophic epithelium, variations of nasal airflow and modifications of the mucociliary clearance. Failure of medical treatments leads to surgery in patients with persistent symptoms and radiographic signs of CRS. The choice of appropriate post-surgical topic treatments is important for healing time and for preventing mucosal complications such as synechiae, crusting formation and atrophy with secondary bacterial and fungal infections. The aim of this study is to definite the effects of topic alpha-tocopherol acetate administration on nasal mucosa healing after endoscopic sinus surgery in CRS of elderly patients. In this study were included 32 patients, mean age 68.6, who underwent FESS because affected by CRS not responsive to medical treatments. After surgical treatment, we distinguish two groups basing on local nasal therapy. In our research, we observed that alpha-tocopherol acetate has no contraindications and side effects. In conclusion, our study showed the effectiveness of alpha-tocopherol acetate topic treatment in elderly patients affected by CRS after FESS, in improving and speeding up the process of restoring the sinonasal mucosa, compared to another topic medication.

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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.

Debbabi M, Nury T, Zarrouk A, Mekahli N, Bezine M, Sghaier R, Grégoire S, Martine L, Durand P, Camus E, Vejux A, Jabrane A, Bretillon L, Prost M, Moreau T, Ammou SB, Hammami M, Lizard G.

Int J Mol Sci. 2016 Nov 25;17(12). pii: E1973.

Abstract

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.

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Klotho sensitive regulation of dendritic cell functions by vitamin E.

Xuan NT, Trang PT, Van Phong N, Toan NL, Trung DM, Bac ND, Nguyen VL, Hoang NH, Van Hai N.

Biol Res. 2016 Nov 24;49(1):45.

Abstract

Dendritic cells (DCs) are the most potent professional antigen-presenting cells for naive T cells to link innate and acquired immunity. Klotho, an anti-aging protein, participates in the regulation of Ca2+ dependent migration in DCs. Vitamin E (VitE) is an essential antioxidant to protect cells from damage and elicits its inhibitory effects on NF-κB-mediated inflammatory response. However, the roles of VitE on mouse DC functions and the contribution of klotho to those effects both are unknown. The present study explored the effects of VitE on klotho expression, maturation, ROS production and migration in DCs.

The mouse bone marrow cells were isolated and cultured with GM-CSF to attain bone marrow-derived DCs (BMDCs). Cells were stimulated with LPS (100 ng/ml) in the presence or absence of VitE (500 µM). RT-PCR and immunoprecipitation methods were employed to determine klotho expression, ELISA to determine cytokine release, flow cytometry to analyze number of CD86+CD11c+cells, the intracellular expression of cytokines and reactive oxygen species (ROS) production and a transwell migration assay to trace migration.

Klotho transcript level and this hormone secretion in DC supernatant were enhanced by VitE treatment and further increased in the presence of NF-κB inhibitor Bay 11-7082 (10 µM). Moreover, VitE treatment inhibited IL-12p70 protein expression of, ROS accumulation in and CCL21-dependent migration of LPS-triggered mature DCs, these effects were reversed following klotho silencing.

The up-regulation of klotho by VitE could contribute to the inhibitory effects of VitE on NF-κB-mediated DC functional maturation. The events might contribute to immunotherapeutic effect of VitE on the pathophysiology of klotho-related disease.

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δ-Tocopherol inhibits receptor tyrosine kinase-induced AKT activation in prostate cancer cells.

Wang H, Hong J, Yang CS.

Mol Carcinog. 2016 Nov;55(11):1728-1738. doi: 10.1002/mc.22422.

Abstract

The cancer preventive activity of vitamin E is suggested by epidemiological studies and supported by animal studies with vitamin Eforms, γ-tocopherol and δ-tocopherol (δ-T). Several recent large-scale cancer prevention trials with high dose of α-tocopherol, however, yielded disappointing results. Whether vitamin E prevents or promotes cancer is a serious concern. A better understanding of the molecular mechanisms of action of the different forms of tocopherols would enhance our understanding of this topic. In this study, we demonstrated that δ-T was the most effective tocopherol form in inhibiting prostate cancer cell growth, by inducing cell cycle arrest and apoptosis. By profiling the effects of δ-T on the cell signaling using the phospho-kinase array, we found that the most inhibited target was the phosphorylation of AKT on T308. Further study on the activation of AKT by EGFR and IGFR revealed that δ-T attenuated the EGF/IGF-induced activation of AKT (via the phosphorylation of AKT on T308 induced by the activation of PIK3). Expression of dominant active PIK3 and AKT in prostate cancer cell line DU145 in which PIK3, AKT, and PTEN are wild type caused the cells to be reflectory to the inhibition of δ-T, supporting that δ-T inhibits the PIK3-mediated activation of AKT. Our data also suggest that δ-T interferes with the EGF-induced EGFR internalization, which leads to the inhibition of the receptor tyrosine kinase-dependent activation of AKT. In summary, our results revealed a novel mechanism of δ-T in inhibiting prostate cancer cell growth, supporting the cancer preventive activity δ-T.

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Vitamin E and the risk of pneumonia: using the I 2 statistic to quantify heterogeneity within a controlled trial.

Hemilä H.

Br J Nutr. 2016 Nov;116(9):1530-1536.

Abstract

Analyses in nutritional epidemiology usually assume a uniform effect of a nutrient. Previously, four subgroups of the Alpha-Tocopherol, Beta-Carotene Cancer Prevention (ATBC) Study of Finnish male smokers aged 50-69 years were identified in which vitamin E supplementation either significantly increased or decreased the risk of pneumonia. The purpose of this present study was to quantify the level of true heterogeneity in the effect of vitamin E on pneumonia incidence using the I 2 statistic. The I 2 value estimates the percentage of total variation across studies that is explained by true differences in the treatment effect rather than by chance, with a range from 0 to 100 %. The I 2 statistic for the effect of vitamin E supplementation on pneumonia risk for five subgroups of the ATBC population was 89 % (95 % CI 78, 95 %), indicating that essentially all heterogeneity was true variation in vitamin E effect instead of chance variation. The I 2 statistic for heterogeneity in vitamin E effects on pneumonia risk was 92 % (95 % CI 80, 97 %) for three other ATBC subgroups defined by smoking level and leisure-time exercise level. Vitamin E decreased pneumonia risk by 69 % among participants who had the least exposure to smoking and exercised during leisure time (7·6 % of the ATBC participants), and vitamin E increased pneumonia risk by 68 % among those who had the highest exposure to smoking and did not exercise (22 % of the ATBC participants). These findings refute there being a uniform effect of vitamin E supplementation on the risk of pneumonia.

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