Displaying publications 1 - 20 of 74 in total

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  1. Ahmad NS, Khalid BA, Luke DA, Ima Nirwana S
    Clin Exp Pharmacol Physiol, 2005 Sep;32(9):761-70.
    PMID: 16173934
    1. Free radicals generated by ferric nitrilotriacetate (FeNTA) can activate osteoclastic activity and this is associated with elevation of the bone resorbing cytokines interleukin (IL)-1 and IL-6. In the present study, we investigated the effects of 2 mg/kg FeNTA (2 mg iron/kg) on the levels of serum IL-1 and IL-6 with or without supplementation with a palm oil tocotrienol mixture or alpha-tocopherol acetate in Wistar rats. 2. The FeNTA was found to elevate levels of IL-1 and IL-6. Only the palm oil tocotrienol mixture at doses of 60 and 100 mg/kg was able to prevent FeNTA-induced increases in IL-1 (P < 0.01). Both the palm oil tocotrienol mixture and alpha-tocopherol acetate, at doses of 30, 60 and 100 mg/kg, were able to reduce FeNTA-induced increases in IL-6 (P < 0.05). Therefore, the palm oil tocotrienol mixture was better than pure alpha-tocopherol acetate in protecting bone against FeNTA (free radical)-induced elevation of bone-resorbing cytokines. 3. Supplementation with the palm oil tocotrienol mixture or alpha-tocopherol acetate at 100 mg/kg restored the reduction in serum osteocalcin levels due to ageing, as seen in the saline (control) group (P < 0.05). All doses of the palm oil tocotrienol mixture decreased urine deoxypyridinoline cross-link (DPD) significantly compared with the control group, whereas a trend for decreased urine DPD was only seen for doses of 60 mg/kg onwards of alpha-tocopherol acetate (P < 0.05). 4. Bone histomorphometric analyses have shown that FeNTA injections significantly lowered mean osteoblast number (P < 0.001) and the bone formation rate (P < 0.001), but raised osteoclast number (P < 0.05) and the ratio of eroded surface/bone surface (P < 0.001) compared with the saline (control) group. Supplementation with 100 mg/kg palm oil tocotrienol mixture was able to prevent all these FeNTA-induced changes, but a similar dose of alpha-tocopherol acetate was found to be effective only for mean osteoclast number. Injections of FeNTA were also shown to reduce trabecular bone volume (P < 0.001) and trabecular thickness (P < 0.05), whereas only supplementation with 100 mg/kg palm oil tocotrienol mixture was able to prevent these FeNTA-induced changes.
    Matched MeSH terms: Tocopherols
  2. Jubri Z, Latif AA, Top AG, Ngah WZ
    Nutr J, 2013;12:2.
    PMID: 23286246 DOI: 10.1186/1475-2891-12-2
    BACKGROUND:
    Cigarette smoke contains free radicals and an have adverse effect to the immune system. Supplementation of palm oil vitamin E (palmvitee), is known has antioxidant properties is thought to be beneficial for system immune protection against free radicals activity. The objective of the study was to determine the effect of palmvitee supplementation on immune response in smokers.

    METHODS:
    This study involved a group of smokers and nonsmokers who received 200 mg/day palmvitee and placebo for the control group. Blood samples were taken at 0, 12 and 24 weeks of supplementation. Plasma tocopherol and tocotrienol were determined by HPLC, lymphocyte proliferation by lymphocyte transformation test (LTT) and enumeration of lymphocytes T and B cells by flow cytometry. Statistical analysis was performed by Mann-Whitney U-test for non-parametric data distribution and correlation among the variables was examined by Spearman.

    RESULTS:
    Plasma tocopherol and tocotrienol were increased in vitamin E supplemented group as compared to placebo group. Urine cotinine levels and serum α1-antitrypsin were significantly higher in smokers compared to nonsmokers. Lymphocyte proliferation induced by PHA showed an increasing trend with palmvitee supplementation in both smokers and nonsmokers. Natural killer cells were decreased; CD4+ cells and B cells were increased in smokers compared to nonsmokers but were unaffected with vitamin E supplementation except in the percentage of B cells which were increased in nonsmokers supplemented palmvitee compared to placebo. CD4+/CD8+ ratio was increased in smokers compared to nonsmokers. The high TWBC count observed in smokers correlated with the increased CD4+ and B cells.

    CONCLUSIONS:
    Smoking caused alterations in certain immune parameters and palmvitee supplementation tended to cause an increase in lymphocytes transformation test but had no effect on CD3+, CD4+, CD8+, NK cells and B cells except B cells percentage in nonsmokers.
    Matched MeSH terms: Tocopherols/administration & dosage*
  3. Khor SC, Razak AM, Wan Ngah WZ, Mohd Yusof YA, Abdul Karim N, Makpol S
    PLoS One, 2016;11(2):e0149265.
    PMID: 26885980 DOI: 10.1371/journal.pone.0149265
    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.
    Matched MeSH terms: Tocopherols/pharmacology*
  4. Hani H, Allaudin ZN, Mohd-Lila MA, Sarsaifi K, Rasouli M, Tam YJ, et al.
    Xenotransplantation, 2017 05;24(3).
    PMID: 28397308 DOI: 10.1111/xen.12302
    BACKGROUND: Dead islets replaced with viable islets are a promising offer to restore normal insulin production to a person with diabetes. The main reason for establishing a new islet source for transplantation is the insufficiency of human donor pancreas while using xenogeneic islets perhaps assists this problem. The expression of PDX1 is essential for the pancreas expansion. In mature β-cells, PDX1 has several critical roles such as glucose sensing, insulin synthesis, and insulin secretion. In this study, we aimed to evaluate the expression of pancreatic duodenal homeobox-1 (PDX1) in treated caprine islets in culture and to assess the protective effects of antioxidant factors on the PDX1 gene in cultured caprine islets.

    MATERIALS AND METHODS: Purified islets were treated with serum-free, serum, IBMX, tocopherol, or IBMX and tocopherol media. Quantitative polymerase chain reaction and Western blotting were carried out to compare the expression levels of PDX1 in treated purified islets cultured with different media.

    RESULTS: Islets treated with IBMX/tocopherol exhibited the highest fold change in the relative expression of PDX1 on day 5 post-treatment (relative expression: 6.80±2.08), whereas serum-treated islets showed the lowest fold changes in PDX1 expression on day 5 post-treatment (0.67±0.36), as compared with the expression on day 1 post-treatment. Insulin production and viability tests of purified islets showed superiority of islet at supplemented serum-free media with IBMX/tocopherol compared to other cultures (53.875%±1.59%).

    CONCLUSIONS: Our results indicated that supplemented serum-free medium with tocopherol and IBMX enhances viability and PDX1 gene expression compared to serum-added and serum-free media.

    Matched MeSH terms: Tocopherols/pharmacology
  5. Cheong JN, Mirhosseini H, Tan CP
    Int J Food Sci Nutr, 2010 Jun;61(4):417-24.
    PMID: 20151850 DOI: 10.3109/09637481003591574
    The main objective of the present study was to investigate the effect of polyoxyethylene sorbitan esters and sodium caseinate on physicochemical properties of palm-based functional lipid nanodispersions prepared by the emulsification-evaporation technique. The results indicated that the average droplet size increased significantly (P < 0.05) by increasing the chain length of fatty acids and also by increasing the hydrophile-lipophile balance value. Among the prepared nanodispersions, the nanoemulsion containing Polysorbate 20 showed the smallest average droplet size (202 nm) and narrowest size distribution for tocopherol-tocotrienol nanodispersions, while sodium caseinate-stabilized nanodispersions containing carotenoids had the largest average droplet size (386 nm), thus indicating a greater emulsifying role for Polysorbate 20 compared with sodium caseinate.
    Matched MeSH terms: Tocopherols
  6. Guthrie N, Gapor A, Chambers AF, Carroll KK
    Asia Pac J Clin Nutr, 1997 Mar;6(1):41-5.
    PMID: 24394652
    Palm oil, unlike many other dietary oils, does not increase the yield of chemically-induced mammary tumors in rats when fed at high levels in the diet. This difference appears to be due to the vitamin E fraction of palm oil, which is rich in tocotrienols, since palm oil stripped of this fraction does increase tumor yields. Experiments in our laboratory have shown that tocotrienols inhibit proliferation and growth of both MDA-MB-435 and MCF-7 cells in culture much more effectively than a-tocopherol. In addition, it was found that combinations of tocotrienols with Tamoxifen, a drug widely used for treatment of breast cancer, inhibit these cells more effectively than either tocotrienols or Tamoxifen alone. The present studies have now shown synergistic effects between tocotrienols and a number of other flavonoids from various plant sources, including citrus fruits, in the inhibition of both MDA-MB-435 and MCF-7 cells (IC50s 0.05-25 and 0.02-5 μg/mL respectively). In the MCF-7 cells, 1:1:1 combinations of tocotrienols, flavonoids and Tamoxifen were even more effective, with the best combination being d-tocotrienol, hesperetin and Tamoxifen (IC50 0.0005 μg/mL). These results suggest that diets containing palm oil may reduce the risk of breast cancer, particularly when eaten with other plant foods containing flavonoids, and may also enhance the effectiveness of Tamoxifen for treatment of breast cancer.
    Matched MeSH terms: Tocopherols
  7. Yuhaniza Shafinie Kamsani, Mohd Hamim Rajikin
    This review summarizes the impact of tocotrienols (TCTs) as antioxidants in minimizing
    oxidative stress (OS), particularly in embryos exposed to OS causing agents. OS level is
    increased, for example, by nicotine, a major alkaloid content in cigarette, which is also a source
    of exogenous reactive oxygen species (ROS). Increased nicotine-induced OS increases cell
    stress response, which is a common trigger leading to embryonic cell death. Having more
    profound anti-oxidative stress effects than its counterpart tocopherol, TCTs improve blastocyst
    implantation, foetal growth, pregnancy outcome and survival of the neonates affected by
    nicotine. In reversing cell developmental arrest caused by nicotine-induced OS, TCTs enhances
    PDK-1 expression in the P13K/Akt pathway and permit embryonic development beyond the 4-
    cell stage with the production of more morulae. At the cytoskeletal level, TCTs increase the
    number of nicotine-induced apoptotic cells, through caspase 8 activation in the mitochondria.
    TCTs facilitate rough endoplasmic reticulum (rER) stress-mediated apoptosis and autophagy,
    resulting from nicotine-induced OS. Reduced vesicular population in TCT supplemented
    oocytes on the other hand may suggest reduced secretion of apoptotic cell bodies thus probably
    minimizing vesicular apoptosis during oocyte maturation. Further extensive research is
    required to develop TCTs as a tool in specific therapeutic approaches to overcome the
    detrimental effects of OS.
    Matched MeSH terms: Tocopherols
  8. Khor, Hun Teik, Ng, Theng Theng, Rajendran, Raajeswari
    Malays J Nutr, 2002;8(2):157-166.
    MyJurnal
    Tocotrienols and tocopherols are isoforms of vitamin E. Vitamin E may exhibit antioxidant, prooxidant and non-antioxidant activities depending upon circumstances. In this study, the effect of tocotrienols and α-tocopherol on the activities of HMG CoA reductase and cholesterol 7 α-hydroxylase was investigated. Pure tocotrienols were isolated from palm fatty acid distillate and pure α-tocopherol was obtained commercially. Guinea pigs were treated with different dosages of tocotrienols and α-tocopherol. After the treatment period, animals were sacrificed and liver microsomes were prepared. HMG CoA reductase and cholesterol 7α-hydroxylase were assayed using tracer techniques. Our results showed that the effects of tocotrienols and α-tocopherol on the activities of both the enzymes were dose-dependent. At low dosages, both tocotrienols and α-tocopherol exhibited an inhibitory effect on both the enzymes. Moreover, tocotrienols were a much stronger inhibitors than α-tocopherol. At high dosages, on the other hand, tocotrienols and α-tocopherol showed opposite effects on the enzymes. While tocotrienols continued to exhibit an inhibitory effect, α-tocopherol actually exhibited a stimulatory effect on both the enzymes. A possible explanation for this observation is suggested.
    Matched MeSH terms: Tocopherols
  9. Fasahat, P., Abdullah, A., Muhammad, K., Wickneswari, R.
    MyJurnal
    Tocochromanols (tocopherols and tocotrienols) unitedly known as vitamin E, are the necessary antioxidant components of both human and animal diets. There is a considerable interest in plants with increased or customized vitamin E content, due to their potential health benefits. To quantify the tocochromanol content and determine the expression of a key tocotrienol biosynthesis gene among a set of contrasting red pericarp and light brown rice genotypes of advanced breeding lines together with their parents; expression pattern of homogentisate geranylgeranyl transferase (HGGT), the key gene was studied by semi-quantitative RT-PCR in milky and matured grain stages. Vitamin E analysis was carried out by high performance liquid chromatography (HPLC). The chloroform-methanolic extracts prepared from red pericarp and light brown rice advanced breeding lines showed significant differences for vitamin E content. Averaged across all samples, the content of γ-tocotrienol > α-tocopherol > α-tocotrienol > γ-tocopherol > δ-tocotrienol, and total E vitamin content ranged from 10.30 to 31.65 µg/g. Genotype G37 (red pericarp) was found to have higher expression than G7 (light brown) and G33 (red pericarp) at both grain development stages but lower than both parents whereas their transcript levels were comparatively lower in mature grain, which indicates their possible regulation by plant growth stage. HPLC results of γ-tocotrienol content supported gene expression results with the exception of the recurrent parent MR219.
    Matched MeSH terms: Tocopherols
  10. Loke, C.Y., Nur Hidayah, M.S., Mohd Fadhli, M.F., Teo, SK, Nor Hidayah, A.G., Yasmin Anum, M.Y., et al.
    Medicine & Health, 2010;5(1):1-12.
    MyJurnal
    Chlorella vulgaris, a unicellular microalgae, produces many intracellular phytochemicals namely carotenoids, tocopherols, ubiquinone and protein. Skin ageing which is induced by oxidative stress involves decreased extracellular matrix synthesis and increased expression of enzymes that degrade the collagenous matrix. The objective of this study was to determine the effect of C. vulgaris on the expression of genes encoded for collagen (COL) and matrix metalloproteinases (MMPs) which are involved in skin ageing. Human diploid fibroblasts (HDFs) were obtained from circumcision foreskin of 8-12 year-old boys. HDFs were cultured into 3 groups: untreated control cells, cells with stress-induced premature senescence (SIPS; cells were induced with H2O2 at passage 6 for 2 weeks) and SIPS treated with C. vulgaris (prolonged C. vulgaris treatment started at passage 4 and combined treatment with H2O2 at passage 6 for 2 weeks). Senescence-associated ß-galactosidase (SA ß-gal) was determined using senescent cells histochemical staining kit (Sigma, USA). Expression of COLI, COLIII, COLIV, MMPI, MMPII and MMPIII genes was quantitatively analysed with real-time RT-PCR method (iScript™ One Step real-time PCR with SYBR® Green; Biorad). HDFs treated with H2O2 (SIPS) exhibited senescent morphological features of flattening and enlarged with increased expression of SA ß-gal (p
    Matched MeSH terms: Tocopherols
  11. Azlina A. Razak, Effat Omar, Suhaila Muid, Hapizah Nawawi
    MyJurnal
    Tocotrienols have been reported to possess potent cholesterol lowering, anti-hypertensive, antiinflammatory and anti-oxidative properties which are superior to tocopherols. Emerging evidence suggests pure tocotrienols have anti-atherogenic properties. However, optimal doses of oftocotrienolrich fraction (TRF) in progressive atherogenesis remain unclear. This animal model experiment was designed to investigate the effects of a range concentration of TRF supplementation on the extent of atherosclerosis and soluble lipids, inflammatory and oxidative stress biomarkers in high-cholesterol diet (HCD) induced hypercholesterolaemic (HC) rabbits with atherosclerosis. A total of 28 New Zealand white rabbits were given 1% high-cholesterol diet (HCD) for two months and then randomised into five groups: Placebo (n=7), TRF 15 mg/kg (n=5), TRF 30 mg/kg (n=6), TRF 60 mg/kg (n=5) and TRF 90 mg/kg (n=5) daily. The treatment was given for three months and the animals were fed HCD throughout the duration. Aortic vessels were obtained to assess the extent of atherosclerotic lesions at the end of the study. Fasting serum lipids (FSL), C-reactive protein (CRP), malondialdehyde (MDA) and 8-isoprostane levels were measured at baseline, one and two months post-HCD, one, two, and three months postintervention. There were no differences in the extent of the atherosclerotic lesions, percentage changes of FSL, MDA, 8-isoprostane and CRP levels between the placebo and TRF groups. In conclusion, TRF across all doses studied have neutral effects on atherosclerotic lesions, soluble lipids, biomarkers of oxidative stress, coronary risk and inflammation in severely atherosclerotic rabbits with progressive and continuous insult by high cholesterol feeding.
    Matched MeSH terms: Tocopherols
  12. Li KS, Ali MA, Muhammad II, Othman NH, Noor AM
    J Oleo Sci, 2018 May 01;67(5):497-505.
    PMID: 29628486 DOI: 10.5650/jos.ess17203
    The impact of microwave roasting on the thermooxidative degradation of perah seed oil (PSO) was evaluated during heating at a frying temperature (170°C). The roasting resulted significantly lower increment of the values of oxidative indices such as free acidity, peroxide value, p-anisidine, total oxidation (TOTOX), specific extinctions and thiobarbituric acid in oils during heating. The colour L* (lightness) value dropped gradually as the heating time increased up to 12 h, whereas a*(redness) and b* (yellowness) tended to increase. The viscosity and total polar compound in roasted PSO was lower as compared to that in unroasted one at each heating times. The tocol retention was also high in roasted samples throughout the heating period. The relative contents of polyunsaturated fatty acids (PUFAs) were decreased to 94.42% and saturated fatty acids (SFAs) were increased to 110.20% in unroasted sample, after 12 h of heating. On the other hand, in 3 min roasted samples, the relative contents of PUFAs were decreased to 98.08% and of SFAs were increased to 103.41% after 12 h of heating. Outcome from analyses showed that microwave roasting reduced the oxidative deteriorations of PSO during heating.
    Matched MeSH terms: Tocopherols
  13. Husam, Y.E., Raha, A.R., Jaafar, M.Z., Mohd Heikal, M.Y.
    MyJurnal
    The pathophysiology of systemic inflammatory response syndrome (SIRS) had been described to involve various strong oxidative reactions affecting the status and progress of the patients. Antioxidant therapy had been suggested in many studies involving SIRS management. The objective of this study was to compare the role of vitamin E Tocotrienol and vitamin E Tocopherol combined with vitamin C as antioxidant therapy in the management of critically ill patients diagnosed with SIRS, admitted to the intensive care unit and high dependency wards of Universiti Kebangsaan Malaysia Medical Centre (UKMMC). It was a single blind randomized clinical trial with a total of 72 patients in which 44.4% Malays, 34.7% Chinese, 19.4% Indians and 1.4% others with 59.7% males and 40.3% females were recruited. Patients in TRI E group received Tocotrienol with Vitamin C while TOCO group received Tocopherol with Vitamin C and a control group did not receive any antioxidant. The clinical parameters (heart rate, respiratory rate, systolic blood pressure) showed improvements with significant difference at the end of study (post-intervention) as compared to admission (pre-intervention).Whereas, the sepsis (temperature, PCT, CRP and WBC) and oxidative stress (8-OHdG/Creatinine) parameters showed improvements with significant difference at the end of study (post-intervention) as compared to admission (pre-intervention). The TRI E group showed obvious improvement in clinical, sepsis and oxidative stress parameters, as compared to TOCO and control groups. This study showed that Vitamin E Tocotrienol and Vitamin E Tocopherol in combination with Vitamin C demonstrated significant improvement in the clinical and laboratory parameters during the management of SIRS. Therefore, Vitamin E in combination with Vitamin C had therapeutic benefits in the treatment of critically ill patients with SIRS.
    Matched MeSH terms: Tocopherols
  14. Yuhaniza Shafinie Kamsani, Mohd Hamim Rajikin
    MyJurnal
    This review summarizes the impact of tocotrienols (TCTs) as antioxidants in minimizing oxidative stress (OS), particularly in embryos exposed to OS causing agents. OS level is increased, for example, by nicotine, a major alkaloid content in cigarette, which is also a source of exogenous reactive oxygen species (ROS). Increased nicotine-induced OS increases cell stress response, which is a common trigger leading to embryonic cell death. Having more profound anti-oxidative stress effects than its counterpart tocopherol, TCTs improve blastocyst implantation, foetal growth, pregnancy outcome and survival of the neonates affected by nicotine. In reversing cell developmental arrest caused by nicotine-induced OS, TCTs enhances PDK-1 expression in the P13K/Akt pathway and permit embryonic development beyond the 4-cell stage with the production of more morulae. At the cytoskeletal level, TCTs increase the number of nicotine-induced apoptotic cells, through caspase 8 activation in the mitochondria. TCTs facilitate rough endoplasmic reticulum (rER) stress-mediated apoptosis and autophagy, resulting from nicotine-induced OS. Reduced vesicular population in TCT supplemented oocytes on the other hand may suggest reduced secretion of apoptotic cell bodies thus probably minimizing vesicular apoptosis during oocyte maturation. Further extensive research is required to develop TCTs as a tool in specific therapeutic approaches to overcome the detrimental effects of OS.
    Matched MeSH terms: Tocopherols
  15. Bong, S.C., Loh, S. P.
    MyJurnal
    This study was conducted to investigate and compare the fatty acids and tocopherols of lipid extracted from marine microalgae, Nannochloropsis oculata (NO) and Tetraselmis suecica (TS) using solvent extraction and supercritical fluid extraction (SFE). Fatty acids and tocopherols were determined in the extracted lipid as functions of the temperature (40, 80oC) and pressure (3000, 5000, 7000, 9000psi). Dichloromethane/methanol and hexane were the chosen conventional solvent for fatty acids and tocopherols extraction respectively. The results obtained showed that there were differences in the fatty acid composition of various lipid extracts of NO and TS. Extracts of NO were high in myristic acid (C14:0) (17-35%), palmitic acid (C16:0) (14-47%) and palmitoleic acid (C16:1) (11-42%) whereas extracts of TS were high in C14:0 (21-34%) and C16:0 (29-49%). Eicosapentaenoic acid (EPA) was detected only under certain SFE conditions in NO but was not detected in TS. α-, β- and γ-tocopherol were detected in various SFE extracts of NO but only α- and β-tocopherol were detected in TS. Hexane extraction of both NO and TS resulted in the detection of only α-tocopherol. In conclusion, the use of different extraction methods resulted in different compositions and concentrations of fatty acids and tocopherols in the microalgae studied.
    Matched MeSH terms: Tocopherols
  16. Makpol S, Jam FA, Khor SC, Ismail Z, Mohd Yusof YA, Ngah WZ
    Oxid Med Cell Longev, 2013;2013:298574.
    PMID: 24396567 DOI: 10.1155/2013/298574
    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.
    Matched MeSH terms: Tocopherols/pharmacology*
  17. Chin KY, Mo H, Soelaiman IN
    Curr Drug Targets, 2013 Dec;14(13):1533-41.
    PMID: 23859472
    Osteoporosis is posing a tremendous healthcare problem globally. Much effort has been invested in finding novel antiosteoporotic agents to stop the progression of this disease. Tocotrienol, one of the isoforms of vitamin E, is poised as a potential antiosteoporotic agent. Previous studies showed that tocotrienol as a single isomer or as a mixture demonstrated both anabolic and antiresorptive effects in various rodent models of osteoporosis. In vitro experiments further demonstrated that tocotrienol could up-regulate genes related to osteoblastogenesis and modify receptor activator of nuclear factor kappa B signaling against osteoclastogenesis. Additionally, tocotrienol was also shown to be a strong 3- hydroxy-3-methyl-glutaryl-CoA reductase down-regulator with a mechanism different from that of statins. Inhibition of the mevalonate pathway affects both osteoblast and osteoclast formation in favor of the former. Tocopherol, a more commonly used isoform of vitamin E does not possess similar effects. Tocotrienol is also a potent antioxidant. It can scavenge free radicals and prevent oxidative damage on osteoblast thus promoting its survival. It may also up-regulate the antioxidant defense network in osteoclast and indirectly act against free radical signaling essential in osteoclastogenesis. The effects of tocotrienol on Wnt/β-catenin signaling essential in osteoblastogenesis have not been determined. More mechanistic studies need to be conducted to illustrate the antiosteoporotic effects of tocotrienol. Clinical trials are also required to confirm its effects in humans. In conclusion, tocotrienol demonstrates great potential as an antiosteoporotic agent and much research effort should be invested to develop it as an agent to curb osteoporosis.
    Matched MeSH terms: Tocopherols/pharmacokinetics
  18. Hermizi H, Faizah O, Ima-Nirwana S, Ahmad Nazrun S, Norazlina M
    Calcif. Tissue Int., 2009 Jan;84(1):65-74.
    PMID: 19020790 DOI: 10.1007/s00223-008-9190-x
    This study was conducted to determine the effectiveness of three forms of vitamin E supplements following nicotine treatment on bone histomorphometric parameters in an adult male rat model. Rats were divided into seven groups: baseline (B, killed without treatment), control (C, normal saline for 4 months), nicotine (N, nicotine for 2 months), nicotine cessation (NC), tocotrienol-enhanced fraction (TEF), gamma-tocotrienol (GTT), and alpha-tocopherol (ATF). Treatments for the NC, TEF, GTT, and ATF groups were performed in two phases. For the first 2 months they were given nicotine (7 mg/kg), and for the following 2 months nicotine administration was stopped and treatments with respective vitamin E preparations (60 mg/kg) were commenced except for the NC group, which was allowed to recover without treatment. Rats in the N and NC groups had lower trabecular bone volume, mineral appositional rate (MAR), and bone formation rate (BFR/BS) and higher single labeled surface and osteoclast surface compared to the C group. Vitamin E treatment reversed these nicotine effects. Both the TEF and GTT groups, but not the ATF group, had a significantly higher trabecular thickness but lower eroded surface (ES/BS) than the C group. The tocotrienol-treated groups had lower ES/BS than the ATF group. The GTT group showed a significantly higher MAR and BFR/BS than the TEF and ATF groups. In conclusion, nicotine induced significant bone loss, while vitamin E supplements not only reversed the effects but also stimulated bone formation significantly above baseline values. Tocotrienol was shown to be slightly superior compared to tocopherol. Thus, vitamin E, especially GTT, may have therapeutic potential to repair bone damage caused by chronic smoking.
    Matched MeSH terms: Tocopherols/pharmacology*
  19. Azlina MF, Nafeeza MI, Khalid BA
    Asia Pac J Clin Nutr, 2005;14(4):358-65.
    PMID: 16326642
    Rats exposed to stress developed various changes in the gastrointestinal tract and hormones. The present study was designed to compare the impact of tocopherol and tocotrienol on changes that influence gastric and hormonal parameters important in maintaining gastric mucosal integrity in rats exposed to restrain stress. These include gastric acidity, gastric tissue content of parameters such as malondialdehyde, prostaglandin (PGE(2)), serum levels of gastrin and glucagon-like peptide-1 (GLP-1). Sixty male Sprague-Dawley rats (200-250 g) were randomly divided into three equal sized groups, a control group which received a normal rat diet (RC) and two treatment groups each receiving a vitamin deficient diet with oral supplementation of either tocopherol (TF) or tocotrienol (TT) at 60 mg/kg body weight. Blood samples were taken from half the number of rats (non-stressed group) after a treatment period of 28 days before they were killed. The remaining half was subjected to experimental restraint-stress, at 2 hours daily for 4 consecutive days (stressed groups), on the fourth day, blood samples were taken and the rats killed. The findings showed that the gastric acid concentration and serum gastrin level in stressed rats were significantly (P<0.05) reduced compared to the non-stressed rats in the control and TF groups. However, the gastric acidity and gastrin levels in the TT group were comparable in stressed and non-stressed rats. These findings suggest that tocotrienol is able to preserve the gastric acidity and serum gastrin level which are usually altered in stressed conditions. The PGE(2) content and the plasma GLP-1 level were, however, comparable in all stressed and non-stressed groups indicating that these parameters were not altered in stress and that supplementation with TF or TT had no effect on the gastric PGE2 content or the GLP-1 level. The malondialdehyde, an indicator of lipid peroxidation was higher from gastric tissues in the stressed groups compared to the non-stressed groups. These findings implicated that free radicals may play a role in the development of gastric injury in stress and supplementation with either TF or TT was able to reduce the lipid peroxidation levels compared to the control rats. We conclude that both tocopherol and tocotrienol are comparable in their gastro-protective ability against damage by free radicals generated in stress conditions, but only tocotrienol has the ability to block the stress-induced changes in the gastric acidity and gastrin level.
    Matched MeSH terms: Tocopherols/pharmacology*
  20. Nafeeza MI, Kang TT
    Int J Vitam Nutr Res, 2005 Mar;75(2):149-55.
    PMID: 15929636
    Nonsteroidal anti-inflammatory drugs and their adverse effects on the gastric mucosa are yet another set of unresolved medical problems. This study examined the effects of various antioxidants on several gastric parameters after a single exposure to indomethacin. Forty-eight male rats of the Sprague-Dawley (200-250 g) strain were randomly divided to receive a single antioxidant (tocopherol, tocotrienol, or ubiquinone) or a combination of two (tocopherol-tocotrienol, tocopherol-ubiquinone or tocotrienol-ubiquinone) for 28 days. The rats were then challenged with a single dose of indomethacin and killed six hours later. Findings showed that the severity of gastric lesions was comparable in all groups. Only groups that received a combination of antioxidants exhibited reduced lipid peroxidation compared with all other groups (p < 0.05). The combination groups had a higher level of gastric prostaglandin E2 (PGE2) content compared with all other groups (p < 0.05). There was no significant difference among the groups in the gastric acid concentration and the glutathione/oxidized glutathione (GSH/GSSG) ratio. We conclude that although supplementation of these antioxidants in combination had desirable effects on lipid peroxidation and gastric PGE2 level, they did not reduce the lesions produced by indomethacin.
    Matched MeSH terms: Tocopherols/administration & dosage*
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