Hordeum spontaneum, wild barley, is the direct progenitor of domestic barley, Hordeum vulgare, an economically important ingredient of animal feed, beer, soy sauce, and more recently, of nutraceuticals. Domestic barley has also been used in the past as a medicine. Barley is a rich source oftocotrienols, with α-tocotrienol being the most prevalent. Wild barley seeds were harvested from ecogeographically diverse areas across the Fertile Crescent, and the tocopherol (α-δ) and tocotrienol (α-δ) contents were determined. Diversity differences in individual and total ‘tocol’ values were significant between and within specific countries, and were significantly correlated with temperature. Wild barley may be used in the future to improve functional qualities of domestic barley. ‘Tocolome’ and ‘tocolomics’ are proposed to encompass all tocols and potentially synergy-enhancing ‘entourage’ compounds that may occur in tocols’ ‘metabolomic neighborhoods’, aiding the standardized manufacture of complex barley derivatives for nutraceutical and pharmaceutical functions.
Antiangiogenic therapy mediated by food components is an established strategy for cancer chemoprevention. Growth factors play critical roles in tumor angiogenesis. A conditioned medium containing growth factors from human gastric adenocarcinoma SGC-7901 cell conditioned medium was used as an angiogenic stimulus in this study. The purpose of this study was to evaluate the inhibitory effect and possible mechanism of γ-tocotrienolon tumor angiogenesis. The results showed that γ-tocotrienol (10-40 μmol/L) significantly suppressed proliferation, migration and tube formation of human umbilical vein endothelial cells (HUVECs) induced by SGC-7901 cell conditioned medium in a dose-dependent manner. γ-Tocotrienol (800-1200 μg/egg) also inhibited new blood vessel formation on the growing chick embryo chorioallantoic membrane in a dose-dependent manner. Moreover, the inhibitory effects of γ-tocotrienol on HUVECs were correlated with inducing the apoptosis and arresting cell cycle at the G(0)/G(1) phase at a dose of 40 μmol/L γ-tocotrienol. In addition, γ-tocotrienol inhibited angiogenesis in HUVECs by down-regulation of β-catenin, cyclin D1, CD44, phospho-VEGFR-2 and MMP-9. The antiangiogenic effects of γ-tocotrienol on HUVECs may be attributable to regulation of Wnt signaling by decreasing β-catenin expression. Thus, our results suggest that γ-tocotrienol has a potential chemopreventive agent via antiangiogenesis.
Background: Changes in immune function believed to contribute to a variety of age-related diseases have been associated with increased production of nitric oxide (NO). We have recently reported that proteasome inhibitors (dexamethasone, mevinolin, quercetin, δ-tocotrienol, and riboflavin) can inhibit lipopolysaccharide (LPS)-induced NO production in vitro by RAW 264.7 cells and by thioglycolate-elicited peritoneal macrophages derived from four strains of mice (C57BL/6, BALB/c, LMP7/MECL-1(-/-) and PPAR-α(-/-) knockout mice). The present study was carried out in order to further explore the potential effects of diet supplementation with naturally-occurring inhibitors (δ-tocotrienol and quercetin) on LPS-stimulated production of NO, TNF-α, and other pro-inflammatory cytokines involved in the ageing process. Young (4-week-old) and senescent mice (42-week old) were fed control diet with or without quercetin (100 ppm), δ-tocotrienol (100 ppm), or dexamethasone (10 ppm; included as positive control for suppression of inflammation) for 4 weeks. At the end of feeding period, thioglycolate-elicited peritoneal macrophages were collected, stimulated with LPS, LPS plus interferon-β (IFN-β), or LPS plus interferon-γ (IFN-γ), and inflammatory responses assessed as measured by production of NO and TNF-α, mRNA reduction for TNF-α, and iNOS genes, and microarray analysis.
Results: Thioglycolate-elicited peritoneal macrophages prepared after four weeks of feeding, and then challenged with LPS (10 ng or 100 ng) resulted in increases of 55% and 73%, respectively in the production of NO of 46-week-old compared to 8-week-old mice fed control diet alone (respective control groups), without affecting the secretion of TNF-α among these two groups. However, macrophages obtained after feeding with quercetin, δ-tocotrienol, and dexamethasone significantly inhibited (30% to 60%; P < 0.02) the LPS-stimulated NO production, compared to respective control groups. There was a 2-fold increase in the production of NO, when LPS-stimulated macrophages of quercetin, δ-tocotrienol, or dexamethasone were also treated with IFN-β or IFN-γ compared to respective control groups. We also demonstrated that NO levels and iNOS mRNA expression levels were significantly higher in LPS-stimulated macrophages from senescent (0.69 vs 0.41; P < 0.05), compared to young mice. In contrast, age did not appear to impact levels of TNF-α protein or mRNA expression levels (0.38 vs 0.35) in LPS-stimulated macrophages. The histological analyses of livers of control groups showed lesions of peliosis and microvesicular steatosis, and treated groups showed Councilman body, and small or large lymphoplasmacytic clusters.
Conclusions: The present results demonstrated that quercetin and δ-tocotrienols inhibit the LPS-induced NO production in vivo. The microarray DNA analyses, followed by pathway analyses indicated that quercetin or δ-tocotrienol inhibit several LPS-induced expression of several ageing and pro-inflammatory genes (IL-1β, IL-1α, IL-6, TNF-α, IL-12, iNOS, VCAM1, ICAM1, COX2, IL-1RA, TRAF1 and CD40). The NF-κB pathway regulates the production of NO and inhibits the pro-inflammatory cytokines involved in normal and ageing process. These ex vivo results confirmed the earlier in vitro findings. The present findings of inhibition of NO production by quercetin and δ-tocotrienol may be of clinical significance treating several inflammatory diseases, including ageing process.
Cyclodextrin (CD) is widely used in the pharmaceutical and nutritional fields to form an inclusion complex with lipophilic compounds for the improvement of their aqueous solubility, stability and diffusibility under physiological conditions. In this study, we investigated the effect of the γ-tocotrienol (γT3) inclusion complex with CD on its oral bioavailability. Five-week-old C57BL6 mice were fed a vitamin E-free diet for 28 days, followed by the oral administration of 2.79 mg of γT3-rich fraction (TRF) extracted from rice bran or the equivalent dose (14.5 mg) of a CD inclusion complex with TRF (TRF/CD). The levels of γT3 in sequentially collected plasma were determined by LC-MS/MS. The pharmacokinetic study revealed that the plasma concentrations of γT3 were increased and peaked at 6 or 3 h after the oral administration of TRF or TRF/CD, respectively (C(max) values of 7.9±3.3 or 11.4±4.5 μM, respectively). The area under the curve of plasma γT3 concentration also showed a 1.4-fold increase in the group administered with TRF/CD compared with the TRF-only group. Furthermore, the mice that had received the TRF/CD tended to reduce the endotoxin shock induced by injection with lethal amounts of Escherichia coli lipopolysaccharide, compared with the mice that had received TRF alone. Taken together, our results suggest that the CD inclusion improved γT3 bioavailability, resulting in the enhancement of γT3 physiological activity, which would be a useful approach for the nutrition delivery system.
BACKGROUND&AIMS: Extracellular matrix deposition is key event for the development of bowel stenosis in Crohn’s disease patients. Transforming growth factor-β plays a key role in this process. We aimed at characterizing the effects of tocotrienol rich fraction on ECM proteins production and molecules that regulate the synthesis and degradation of extracellular matrix, matrix metalloproteinase-3 and tissue inhibitor of metalloproteinases-1, in human intestinal fibroblasts, and at elucidating whether the effects of tocotrienol rich fraction (TRF) are mediated through inhibition of TGF-β1.
METHODS: HIF were isolated from colonic or ileal tissue from Crohn’s disease patients and control subjects, and were treated with TRF from palm oil either alone or in combination with TGF-β1. Procollagen 1, procollagen 3, TIMP-1 and MMP-3 production, and Smad3 phosphorylation were analyzed by Western-blotting.
RESULTS: TRF significantly diminished procollagen 1 and 3 synthesis in HIF. Treatment of HIF with TRF increased MMP-3 production but did not modify TIMP-1. TGF-β1 induced Smad3 phosphorylation and enhanced procollagen 1 and 3 and TIMP-1 production. Pre-treatment of HIF with TRF prevented Smad3 phosphorylation and minimized the increase in collagen 1 and 3 production caused by TGF-β1.
CONCLUSIONS: TRF has anti-fibrogenic effects on HIF, decreasing ECM production and increasing its degradation. This effect is mediated, at least in part, by inhibition of TGF-β1
Objectives: Aberrant Met signalling is associated with aggressive cancer cell phenotypes. γ-tocotrienol displays potent anti-cancer activity that is associated with suppression of HER⁄ErbB receptor signalling. Experiments were conducted to investigate the effects of γ-tocotrienol treatment on HGF-dependent +SA mammary tumour cell proliferation, upon Met activation.
Materials and Methods: The +SA cells were maintained in serum-free defined media containing 10 ng ⁄ml HGF as the mitogen. Cell viability was determined using the MTT assay, western blot analysis was used to measure protein expression, and Met expression and activation were determined using immunofluorescent staining.
Results and Conclusions: Treatment with γ-tocotrienol or Met inhibitor, SU11274, significantly inhibited HGF-dependent +SA cell replication in a dose– responsive manner. Treatment with 4 lM c-tocotrienol reduced both total Met levels and HGF-induced Met autophosphorylation. In contrast, similar treatment with 5.5 lM SU11274 inhibited HGF-induced Met autophosphorylation, but had no effect on total Met levels. Combined treatment with subeffective doses of c-tocotrienol (2 lM) and SU11274 (3 lM) resulted in significant inhibition of +SA cell expansion compared to treatment with individual agents alone. These findings show, for the first time, the inhibitory effects of c-tocotrienol on Met expression and activation, and strongly suggest that c-tocotrienol treatment may provide significant health benefits in prevention and ⁄ or treatment of breast cancer, in women with deregulated HGF⁄Met signalling.
The NF-kappaB transcription factor functions as a crucial regulator of cell survival and chemoresistance in pancreatic cancer. Recent studies suggest that tocotrienols, which are the unsaturated forms of vitamin E, are a promising class of anticancer compounds that inhibit the growth and survival of many cancer cells, including pancreatic cancer. Here, we show that tocotrienols inhibited NF-kappaB activity and the survival of human pancreatic cancer cells in vitro and in vivo. Importantly, we found the bioactivity of the four natural tocotrienol compounds (alpha-, beta-, delta-, and gamma-tocotrienol) to be directly related to their ability to suppress NF-kappaB activity in vitro and in vivo. The most bioactive tocotrienol for pancreatic cancer, delta-tocotrienol, significantly enhanced the efficacy of gemcitabine to inhibit pancreatic cancer growth and survival in vitro and in vivo. Moreover, we found that delta-tocotrienol augmentation of gemcitabine activity in pancreatic cancer cells and tumors is associated with significant suppression of NF-kappaB activity and the expression of NF-kappaB transcriptional targets (Bcl-X(L), X-linked inhibitor of apoptosis, and survivin). Our study represents the first comprehensive preclinical evaluation of the activity of natural vitamin E compounds in pancreatic cancer. Given these results, we are conducting a phase I trial of delta-tocotrienol in patients with pancreatic cancer using pancreatic tumor cell survival and NF-kappaB signaling components as intermediate biomarkers. Our data also support future clinical investigation of delta-tocotrienol to augment gemcitabine activity in pancreatic cancer.
Byron J. Richards,
The kidneys may be the weak link in the chain when it comes to problems with blood pressure and blood sugar, which are at epidemic levels in America. Nutrients that help protect the kidneys are likely to save untold health misery for potentially millions of people. A new study by University of Arkansas researchers shows that gamma tocotrienol has potent kidney-protecting properties.