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

Matthaus B, Özcan MM, Al Juhaimi F.

Z Naturforsch C. 2016 Mar;71(3-4):73-7. doi: 10.1515/znc-2016-0003.

Abstract

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 (p<0.05). The oil contents of rapeseeds were found to be high compared with canola seed oils. The main fatty acids in the oils are oleic (56.80-64.92%), linoleic (17.11-20.92%) and palmitic (4.18-5.01%) acids. A few types of tocopherols 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%) (p<0.05). As a result, the present study shows that oil, fatty acid and tocopherol contents differ significantly among the cultivars.

Schmölz L, Birringer M, Lorkowski S, Wallert M.

World J Biol Chem. 2016 Feb 26;7(1):14-43. doi: 10.4331/wjbc.v7.i1.14. Review.

Abstract

Bioavailability of vitamin E is influenced by several factors, most are highlighted in this review. While gender, age and genetic constitution influence vitamin E bioavailability but cannot be modified, life-style and intake of vitamin E can be. Numerous factors must be taken into account however, i.e., when vitamin E is orally administrated, the food matrix may contain competing nutrients. The complex metabolic processes comprise intestinal absorption, vascular transport, hepatic sorting by intracellular binding proteins, such as the significant α-tocopherol-transfer protein, and hepatic metabolism. The coordinated changes involved in the hepatic metabolism of vitamin E provide an effective physiological pathway to protect tissues against the excessive accumulation of, in particular, non-α-tocopherol forms. Metabolism of vitamin E begins with one cycle of CYP4F2/CYP3A4-dependent ω-hydroxylation followed by five cycles of subsequent β-oxidation, and forms the water-soluble end-product carboxyethylhydroxychroman. All known hepatic metabolites can be conjugated and are excreted, depending on the length of their side-chain, either via urine or feces. The physiological handling of vitamin E underlies kinetics which vary between the different vitamin E forms. Here, saturation of the side-chain and also substitution of the chromanol ring system are important. Most of the metabolic reactions and processes that are involved with vitamin E are also shared by other fat soluble vitamins. Influencing interactions with other nutrients such as vitamin K or pharmaceuticals are also covered by this review. All these processes modulate the formation of vitamin E metabolites and their concentrations in tissues and body fluids. Differences in metabolism might be responsible for the discrepancies that have been observed in studies performed in vivo and in vitro using vitamin E as a supplement or nutrient. To evaluate individual vitamin E status, the analytical procedures used for detecting and quantifying vitamin E and its metabolites are crucial. The latest methods in analytics are presented.

Hanson C, Lyden E, Furtado J, Campos H, Sparrow D, Vokonas P, Litonjua AA.

Clin Nutr. 2016 Feb;35(1):169-74. doi: 10.1016/j.clnu.2015.01.020.

Abstract

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. In this study, there is a positive association between dietary vitamin E intake and lung function, and evidence of an inverse relationship between serum levels of γ-tocopherol and lung function.

Takahashi K, Takisawa S, Shimokado K, Kono N, Arai H, Ishigami A.

Eur J Nutr. 2016 Feb 18. [Epub ahead of print]

Abstract

Despite numerous studies on the RRR- and all-rac-α-tocopherol isoform of vitamin E (VE) during aging, this relationship has not been examined in specific tissues. Since α-tocopherol is the most abundant of VE’s eight isoforms, and VE is an important antioxidant that impacts the aging process, we analyzed α-tocopherol levels in plasma and tissues of mice at progressive ages. Moreover, we examined protein and mRNA expression levels of hepatic α-tocopherol transfer protein (α-TTP), which specifically binds α-tocopherol, during aging. The α-tocopherol levels in plasma, liver, cerebrum, hippocampus, cerebellum, heart, kidney, epididymal adipose tissue, testis, pancreas, soleus muscle, plantaris muscle, and duodenum from male C57BL/6NCr mice at 3, 6, 12, 18, and 24 months of age were determined by HPLC and fluorescence detection. Also, hepatic α-TTP protein and mRNA expression levels were analyzed by Western blot and qPCR, respectively. Based on the result obtained, the tissue-specific, age-related changes of α-tocopherol levels normalized by tissue weight were observed in the liver, cerebrum, hippocampus, cerebellum, heart, kidney, and epididymal adipose tissue. Specifically, α-tocopherol levels in epididymal adipose tissue increased greatly as mice aged from 6 to 24 months. Although hepatic α-TTP protein levels also showed age-related changes, α-TTP mRNA expression levels measured after overnight fasting were not altered. In this study, we determined that α-tocopherol levels and hepatic α-TTP protein levels of mice undergo significant tissue-specific, age-related changes. This is the first report to investigate VE in terms of the α-tocopherol levels in plasma and various tissues of mice and hepatic α-TTP protein levels during aging.

Khor SC, Razak AM, Wan Ngah WZ, Mohd Yusof YA, Abdul Karim N, Makpol S.

PLoS One. 2016 Feb 17;11(2):e0149265. doi: 10.1371/journal.pone.0149265.

Abstract

Aging results in a loss of muscle mass and strength. Myoblasts play an important role in maintaining muscle mass through regenerative processes, which are impaired during aging. Vitamin E potentially ameliorates age-related phenotypes. Hence, this study aimed to determine the effects of the tocotrienol-rich fraction (TRF) and α-tocopherol (ATF) in protecting myoblasts from replicative senescence and promoting myogenic differentiation. Primary human myoblasts were cultured into young and senescent stages and were then treated with TRF or ATF for 24 h, followed by an analysis of cell proliferation, senescence biomarkers, cellular morphology and differentiation. Our data showed that replicative senescence impaired the normal regenerative processes of myoblasts, resulting in changes in cellular morphology, cell proliferation, senescence-associated β-galactosidase (SA-β-gal) expression, myogenic differentiation and myogenic regulatory factors (MRFs) expression. Treatment with both TRF and ATF was beneficial to senescent myoblasts in reclaiming the morphology of young cells, improved cell viability and decreased SA-β-gal expression. However, only TRF treatment increased BrdU incorporation in senescent myoblasts, as well as promoted myogenic differentiation through the modulation of MRFs at the mRNA and protein levels. MYOD1 and MYOG gene expression and myogenin protein expression were modulated in the early phases of myogenic differentiation. In conclusion, the tocotrienol-rich fraction is superior to α-tocopherol in ameliorating replicative senescence-related aberration and promoting differentiation via modulation of MRFs expression, indicating vitamin E potential in modulating replicative senescence of myoblasts.

Wang SW, Yang SG, Liu W, Zhang YX, Xu PX, Wang T, Ling TJ, Liu RT.

Behav Brain Res. 2016 Jan 1;296:109-17. doi: 10.1016/j.bbr.2015.09.003.

Abstract

The pathologies of Alzheimer’s disease (AD) is associated with soluble beta-amyloid (Aβ) oligomers, neuroinflammation and oxidative stress. Decreasing the levels of Aβ oligomer, glial activation and oxidative stress are potential therapeutic approaches for AD treatment. We previously found alpha-tocopherol quinine (α-TQ) inhibited Aβ aggregation and cytotoxicity, decreased the release of inflammatory cytokines and reactive oxygen species (ROS) in vitro. However, whether α-TQ ameliorates memory deficits and other neuropathologies in mice or patients with AD remains unknown. In this study, we reported that orally administered α-TQ ameliorated memory impairment in APPswe/PS1dE9 transgenic mice, decreased oxidative stress and the levels of Aβ oligomer in the brains of mice, prevented the production of inducible nitric oxide synthase and inflammatory mediators, such as interleukin-6 and interleukin-1β, and inhibited microglial activation by inhibiting NF-κB signaling pathway. These findings suggest that α-TQ has potential therapeutic value for AD treatment.

Sharma VK, Mamontov E, Tyagi M, Urban VS.

J Phys Chem B. 2016 Jan 14;120(1):154-63. doi: 10.1021/acs.jpcb.5b10417.

Abstract

Vitamin E behaves as an antioxidant and is well known for its protective properties of the lipid membrane. The most biologically active form of vitamin E in the human organism is α-tocopherol (aToc). Very recently (Marquardt, D.; et al. J. Am. Chem. Soc. 2014, 136, 203-210) it has been shown that aToc resides near the center of dimyristoylphosphatidylcholine (DMPC) bilayer, which is in stark contrast with other PC membranes, where aToc is located near the lipid-water interface. Here we report an unusual effect of this exceptional location of aToc on the dynamical behavior of DMPC membrane probed by incoherent elastic and quasielastic neutron scattering. For pure DMPC vesicles, elastic scan data show two step-like drops in the elastic intensity at 288 and 297 K, which correspond to the pre- and main phase transitions, respectively. However, inclusion of aToc into DMPC membrane inhibits the step-like elastic intensity drops, indicating a significant impact of aToc on the phase behavior of the membrane. This observation is supported by our differential scanning calorimetry data, which shows that inclusion of aToc leads to a significant broadening of the main phase transition peak, whereas the peak corresponding to the pretransition disappears. We have performed quasielastic neutron scattering (QENS) measurements on DMPC vesicles with various concentrations of aToc at 280, 293, and 310 K. We have found that aToc affects both the lateral diffusion and the internal motions of the lipid molecules. Below the main phase transition temperature inclusion of aToc accelerates both the lateral and the internal lipid motions. On the other hand, above the main phase transition temperature the addition of aToc restricts only the internal motion, without a significant influence on the lateral motion. Our results support the finding that the location of aToc in DMPC membrane is deep within the bilayer.

Caraffa AL, Varvara G, Spinas E, Kritas SK, Lessiani G, Ronconi G, Saggini A, Antinolfi P, Frydas I, De Tommaso Morrison MC, Conti P.

J Biol Regul Homeost Agents. 2016 Jan-Mar;30(1):11-5. Review.

Abstract

Vitamin E is found in eight forms in nature which include four tocopherols (alpha, beta, gamma and delta) and four tocotrianols (alpha, beta, gamma and delta). The classic effect of vitamin E is to reduce and prevent oxygen damage to the tissue and is useful for the treatment of pain, inflammation and allergic reactions. In addition to antioxidant activity, vitamin E also has a number of different and related functions. It protects against cancer, improves immune response, lowers the incidence of infectious diseases, cardiovascular diseases and is protective in allergy and asthma risk, and other disorders. Vitamin E increases n-6 polyunsaturated fatty acid (PUFA) and decreases n-3 PUFA, an effect that diminishes asthma and allergic diseases. Moreover, vitamin E regulates vascular cell adhesion molecule-1 (VCAM-1)-dependent leukocyte migration through its oxidant and non-antioxidant effect. Furthermore, vitamin E modulates the endothelial function by altering VCAM-1-induced oxidative activation of endothelial cell PKCα. However, vitamin E is not consistently associated with asthma and/or allergy, and in some cases there are conflicting results on allergy and inflammatory diseases. The association of vitamin E and allergy appears to be very complex, and further study needs to clarify this dilemma.

Malavolta M, Pierpaoli E, Giacconi R, Costarelli L, Piacenza F, Basso A, Cardelli M, Provinciali M.

Curr Drug Targets. 2016;17(4):447-59. Review.

Abstract

The possibility to target cellular senescence with natural bioactive substances open interesting therapeutic perspective in cancer and aging. Engaging senescence response is suggested as a key component for therapeutic intervention in the eradication of cancer. At the same time, delaying senescence or even promote death of accumulating apoptosis-resistant senescent cells is proposed as a strategy to prevent age related diseases. Although these two desired outcome present an intrinsic dichotomy, there are examples of promising natural compounds that appear to satisfy all the requirements to develop senescence- targeted health promoting nutraceuticals. Tocotrienols (T3s) and quercetin (QUE), albeit belonging to different phytochemical classes, display similar and promising effects “in vitro” when tested in normal and cancer cells. Both compounds have been shown to induce senescence and promote apoptosis in a multitude of cancer lines. Conversely, they display senescence delaying activity in primary cells and rejuvenating effects in senescent cells. More recently, QUE has been shown to display senolytic effects in some primary senescent cells, likely as a consequence of its inhibitory effects on specific anti-apoptotic genes (i.e. PI3K and other kinases). Senolytic activity has not been tested for T3s but part of metabolic and apoptotic pathways affected by these compounds in cancer cells overlap with those of QUE. This suggests that the rejuvenating effects of T3s and QUE on pre-senescent and senescent primary cells might be the net results of a senolytic activity on senescent cells and a selective survival of a sub-population of non-senescent cells in the culture. The meaning of this hypothesis in the context of adjuvant therapy of cancer and preventive anti-aging strategies with QUE or T3s is discussed.

Koufaki M.

Expert Opin Ther Pat. 2016;26(1):35-47. doi: 10.1517/13543776.2016.1106476. Review.

Abstract

The vitamin E family consists of four tocopherols and four tocotrienols. α-Tocopherol is the most studied member of this family for its antioxidant and non-antioxidant properties, while tocotrienols have attracted recent research interest. The structural motifs of the vitamin E family and specifically the chroman moiety, are amenable to various modifications in order to improve their bioactivities towards numerous therapeutic targets. This review includes the patent literature from 2010 – 2015 related to vitamin E derivatives and it is focused on 2-, 5- or 6-substituted chroman analogues. The patent search was performed using Reaxys® and esp@cenet. The chroman moiety of vitamin E is a privileged structure and an essential pharmacophore which inspired organic chemists to synthesize new analogues with improved bioactivities. Modifications at the 2- and 5- positions of the chroman ring resulted in very interesting active compounds in cellular and animal models of diseases related to oxidative stress. More recent publications and patents reported 6-substituted chromans as anticancer agents in vitro and in vivo. Additionally, an emerging interest is observed towards the use of vitamin E analogues incorporated in drug delivery systems and for medical imaging as contrast agents or fluorescent probes.