Displaying publications 1 - 20 of 85 in total

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  1. Lim SW, Loh HS, Ting KN, Bradshaw TD, Zeenathul NA
    PMID: 25480449 DOI: 10.1186/1472-6882-14-469
    Tocotrienols, especially the gamma isomer was discovered to possess cytotoxic effects associated with the induction of apoptosis in numerous cancers. Individual tocotrienol isomers are believed to induce dissimilar apoptotic mechanisms in different cancer types. This study was aimed to compare the cytotoxic potency of alpha-, gamma- and delta-tocotrienols, and to explore their resultant apoptotic mechanisms in human lung adenocarcinoma A549 and glioblastoma U87MG cells which are scarcely researched.
    Matched MeSH terms: Tocotrienols/pharmacology
  2. Abdul Nasir NA, Agarwal R, Sheikh Abdul Kadir SH, Vasudevan S, Tripathy M, Iezhitsa I, et al.
    PLoS One, 2017;12(3):e0174542.
    PMID: 28350848 DOI: 10.1371/journal.pone.0174542
    Cataract, a leading cause of blindness, is of special concern in diabetics as it occurs at earlier onset. Polyol accumulation and increased oxidative-nitrosative stress in cataractogenesis are associated with NFκB activation, iNOS expression, ATP depletion, loss of ATPase functions, calpain activation and proteolysis of soluble to insoluble proteins. Tocotrienol was previously shown to reduce lens oxidative stress and inhibit cataractogenesis in galactose-fed rats. In current study, we investigated anticataract effects of topical tocotrienol and possible mechanisms involved in streptozotocin-induced diabetic rats. Diabetes was induced in Sprague Dawley rats by intraperitoneal injection of streptozotocin. Diabetic rats were treated with vehicle (DV) or tocotrienol (DT). A third group consists of normal, non-diabetic rats were treated with vehicle (NV). All treatments were given topically, bilaterally, twice daily for 8 weeks with weekly slit lamp monitoring. Subsequently, rats were euthanized and lenses were subjected to estimation of polyol accumulation, oxidative-nitrosative stress, NFκB activation, iNOS expression, ATP levels, ATPase activities, calpain activity and total protein levels. Cataract progression was delayed from the fifth week onwards in DT with lower mean of cataract stages compared to DV group (p<0.01) despite persistent hyperglycemia. Reduced cataractogenesis in DT group was accompanied with lower aldose reductase activity and sorbitol level compared to DV group (p<0.01). DT group also showed reduced NFκB activation, lower iNOS expression and reduced oxidative-nitrosative stress compared to DV group. Lenticular ATP and ATPase and calpain 2 activities in DT group were restored to normal. Consequently, soluble to insoluble protein ratio in DT group was higher compared to DV (p<0.05). In conclusion, preventive effect of topical tocotrienol on development of cataract in STZ-induced diabetic rats could be attributed to reduced lens aldose reductase activity, polyol levels and oxidative-nitrosative stress. These effects of tocotrienol invlove reduced NFκB activation, lower iNOS expression, restoration of ATP level, ATPase activities, calpain activity and lens protein levels.
    Matched MeSH terms: Tocotrienols/pharmacology*
  3. Abdul Nasir NA, Agarwal R, Vasudevan S, Tripathy M, Alyautdin R, Ismail NM
    Mol Vis, 2014;20:822-35.
    PMID: 24940038
    Oxidative and nitrosative stress underlies cataractogenesis, and therefore, various antioxidants have been investigated for anticataract properties. Several vitamin E analogs have also been studied for anticataract effects due to their antioxidant properties; however, the anticataract properties of tocotrienols have not been investigated. In this study, we investigated the effects of topically applied tocotrienol on the onset and progression of cataract and lenticular oxidative and nitrosative stress in galactosemic rats.
    Matched MeSH terms: Tocotrienols/pharmacology
  4. Kamisah Y, Lim JJ, Lim CL, Asmadi AY
    PLoS One, 2014;9(2):e89248.
    PMID: 24586630 DOI: 10.1371/journal.pone.0089248
    Phenylhydrazine, a hemolytic agent, is widely used as a model of experimental hyperbilirubinemia. Palm tocotrienol-rich fraction (TRF) was shown to exert beneficial effects in hyperbilirubinemic rat neonates.
    Matched MeSH terms: Tocotrienols/pharmacology*
  5. Ibrahim N', Mohamed N, Soelaiman IN, Shuid AN
    Int J Environ Res Public Health, 2015 Oct;12(10):12958-76.
    PMID: 26501302 DOI: 10.3390/ijerph121012958
    Osteoporotic drugs are used to prevent fragility fractures, but their role in fracture healing still remains unknown. Thus, alternative agents with suitable mode of delivery are needed to promote fracture healing. This study was performed to investigate the effects of direct deliveries of lovastatin and tocotrienol to fracture sites on ossification-related gene expression in fracture healing in a postmenopausal osteoporosis model. Forty-eight Sprague Dawley female rats were divided into six groups. Group I comprised the sham-operated rats, while Groups II-VI were ovariectomized rats. After 8 weeks, the right tibiae of all rats were fractured and stabilized. Group I and Group II were given two single injections of lovastatin and tocotrienol carriers. Group III was given an estrogen preparation at 64.5 µg/kg daily via oral gavages. Group IV was injected with lovastatin particles (750 µg/kg), while Group V was injected with tocotrienol particles (60 mg/kg). Group VI received two single injections of 750 µg/kg lovastatin particles and 60 mg/kg tocotrienol particles. After 4 weeks, the gene expressions were measured. Group VI showed significantly higher gene expressions of osteocalcin, BMP-2, VEGF-α, and RUNX-2 compared to Group II. In conclusion, combined treatment of lovastatin and tocotrienol upregulated the expression of genes related to fracture healing.
    Matched MeSH terms: Tocotrienols/pharmacology*
  6. 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: Tocotrienols/pharmacology*
  7. Abdul Rahman Sazli F, Jubri Z, Abdul Rahman M, Karsani SA, Md Top AG, Wan Ngah WZ
    PMID: 25886747 DOI: 10.1186/s12906-015-0590-y
    To determine the antiproliferative effect of gamma-tocotrienol (GTT) treatment on differential protein expression in HepG2 cells.
    Matched MeSH terms: Tocotrienols/pharmacology*
  8. Nafeeza MI, Fauzee AM, Kamsiah J, Gapor MT
    Asia Pac J Clin Nutr, 2002;11(4):309-13.
    PMID: 12495264
    This study examined the effects of a tocotrienol-rich fraction (TRF) obtained from palm oil on the healing of aspirin-induced gastric mucosal lesions. Thirty-six male Sprague-Dawley rats (200-250 g) were randomly divided into three groups. Group I was fed a vitamin E-deficient diet (control), Group II was fed a vitamin E-deficient diet supplemented with tocopherol (300 mg/kg food) and Group III was fed a vitamin E-deficient diet supplemented with TRF (300 mg/kg food). After eight weeks, the control and treated groups received a single intragastric dose of 400 mg/kg body weight aspirin. The rats were killed 24 h after exposure to aspirin. Assessment of gastric lesions showed a lower gastric lesion index in the TRF (P = 0.0005) and tocopherol groups (P = 0.0008) compared to the control. The gastric malondialdehyde (MDA) content was also lower in the TRF (P = 0.025) and tocopherol groups (P = 0.025) compared to control. There were, however, no significant differences in the gastric lesion index and gastric MDA content between the TRF and tocopherol-fed groups. There were no significant differences in the adherent gastric mucous concentration and gastric acid concentration among all groups. We conclude that the TRF and tocopherol are equally effective in preventing aspirin-induced gastric lesions. The most probable mechanism is through their ability to limit lipid peroxidation, which is involved in aspirin-induced gastric lesions.
    Matched MeSH terms: Tocotrienols/pharmacology
  9. Nur Azlina MF, Qodriyah HMS, Chua KH, Kamisah Y
    World J Gastroenterol, 2017 Aug 28;23(32):5887-5894.
    PMID: 28932080 DOI: 10.3748/wjg.v23.i32.5887
    AIM: To investigate and compare the effects of tocotrienol and omeprazole on gastric growth factors in rats exposed to water-immersion restraint stress (WIRS).

    METHODS: Twenty-eight male Wistar rats were randomly assigned to four groups of seven rats. The two control groups were administered vitamin-free palm oil (vehicle) and the two treatment groups were given omeprazole (20 mg/kg) or tocotrienol (60 mg/kg) by oral gavage. After 28 d of treatment, rats from one control group and both treated groups were subjected to WIRS one time for 3.5 h. Gastric lesions were measured and gastric tissues were obtained to measure vascular endothelial growth factor (VEGF), epidermal growth factor (EGF), basic fibroblast growth factor (bFGF), and transforming growth factor-alpha (TGF-α) mRNA expression.

    RESULTS: Rats exposed to WIRS for 3.5 h demonstrated the presence of considerable ulcers in the form of gastric erosion. The lesion index in the stressed control (S) group was increased (P < 0.001) compared to the tocotrienol treated and omeprazole treated groups. Stress led to a decrease in gastric VEGF (P < 0.001), bFGF (P < 0.001) and TGF-α (P < 0.001) mRNA levels and caused an increase in EGF mRNA (P < 0.001) that was statistically significant compared to the non-stressed control group. Although both treatment agents exerted similar ulcer reducing ability, only treatment with tocotrienol led to increased expression of VEGF (P = 0.008), bFGF (P = 0.001) and TGF-α (P = 0.002) mRNA.

    CONCLUSION: Tocotrienol provides gastroprotective effects in WIRS-induced ulcers. Compared to omeprazole, tocotrienol exerts a similar protective effect, albeit through multiple mechanisms of protection, particularly through up-regulation of growth factors that assist in repair of gastric tissue injuries.

    Matched MeSH terms: Tocotrienols/pharmacology*
  10. Che HL, Kanthimathi MS, Loganathan R, Yuen KH, Tan AT, Selvaduray KR, et al.
    Eur J Clin Nutr, 2017 01;71(1):107-114.
    PMID: 27759074 DOI: 10.1038/ejcn.2016.200
    BACKGROUND/OBJECTIVES: Evidence shows that tocotrienols potentially reverse various chronic disease progressions caused by the metabolic syndrome. We aimed to investigate the acute effects of a single-dose supplementation of gamma and delta tocotrienols (γδ-T3, 1:4 ratio) compared with those in placebo on the insulinemic, anti-inflammatory and anti-thrombogenic responses in metabolic syndrome subjects.

    SUBJECTS/METHODS: Thirty metabolic syndrome subjects (15 men and 15 women) were recruited to a randomized, double-blinded and crossover study. The subjects were administered a single dose of 200 mg or 400 mg γδ-T3 emulsions or placebo incorporated into a glass of strawberry-flavored milkshake, consumed together with a high-fat muffin. Blood samples were collected at 0, 5, 15, 30, 60, 90, 120, 180, 240, 300 and 360 min after meal intake.

    RESULTS: Plasma vitamin E levels reflected the absorption of γδ-T3 after treatments. Postprandial changes in serum C-peptide, serum insulin, plasma glucose, triacylglycerol, non-esterified fatty acid and adiponectin did not differ between treatments, with women displaying delayed increase in the aforementioned markers. No significant difference between treatments was observed for plasma cytokines (interleukin-1 beta, interleukin-6 and tumor necrosis factor alpha) and thrombogenic markers (plasminogen activator inhibitor type 1 and D-dimer).

    CONCLUSIONS: Supplementation of a single dose of γδ-T3 did not change the insulinemic, anti-inflammatory and anti-thrombogenic responses in metabolic syndrome subjects.

    Matched MeSH terms: Tocotrienols/pharmacology*
  11. Chin KY, Gengatharan D, Mohd Nasru FS, Khairussam RA, Ern SL, Aminuddin SA, et al.
    Nutrients, 2016 Dec 14;8(12).
    PMID: 27983628
    Osteoporosis reduces the skeletal strength and increases the risk for fracture. It is an underdiagnosed disease in men. Annatto tocotrienol has been shown to improve bone structural indices and increase expression of bone formation genes in orchidectomized rats. This study aimed to evaluate the effects of annatto tocotrienol on biomechanical strength and calcium content of the bone in orchidectomized rats. Thirty three-month-old male Sprague-Dawley rats were randomly assigned to five groups. The baseline control (BC) group was sacrificed at the onset of the study. The sham-operated group (SHAM) received olive oil (the vehicle of tocotrienol) orally daily and peanut oil (the vehicle of testosterone) intramuscularly weekly. The remaining rats were orchidectomized and treated with three different regimens, i.e., (1) daily oral olive oil plus weekly intramuscular peanut oil injection; (2) daily oral annatto tocotrienol at 60 mg/kg plus weekly intramuscular peanut oil injection; (3) daily oral olive oil plus weekly intramuscular testosterone enanthate injection at 7 mg/kg. Blood, femur and tibia of the rats were harvested at the end of the two-month treatment period for the evaluation of serum total calcium and inorganic phosphate levels, bone biomechanical strength test and bone calcium content. Annatto-tocotrienol treatment improved serum calcium level and tibial calcium content (p < 0.05) but it did not affect femoral biomechanical strength (p > 0.05). In conclusion, annatto-tocotrienol at 60 mg/kg augments bone calcium level by preventing calcium mobilization into the circulation. A longer treatment period is needed for annatto tocotrienol to exert its effects on bone strength.
    Matched MeSH terms: Tocotrienols/pharmacology*
  12. Mohamad NV, Ima-Nirwana S, Chin KY
    Drug Des Devel Ther, 2018;12:555-564.
    PMID: 29588572 DOI: 10.2147/DDDT.S158410
    Background: Patients receiving androgen deprivation therapy experience secondary hypogonadism, associated bone loss, and increased fracture risk. It has been shown that tocotrienol from Bixa orellana (annatto) prevents skeletal microstructural changes in rats experiencing primary hypogonadism. However, its potential in preventing bone loss due to androgen deprivation therapy has not been tested. This study aimed to evaluate the skeletal protective effects of annatto tocotrienol using a buserelin-induced osteoporotic rat model.

    Methods: Forty-six male Sprague Dawley rats aged 3 months were randomized into six groups. The baseline control (n=6) was sacrificed at the onset of the study. The normal control (n=8) received corn oil (the vehicle of tocotrienol) orally daily and normal saline (the vehicle of buserelin) subcutaneously daily. The buserelin control (n=8) received corn oil orally daily and subcutaneous buserelin injection (75 µg/kg) daily. The calcium control (n=8) was supplemented with 1% calcium in drinking water and daily subcutaneous buserelin injection (75 µg/kg). The remaining rats were given daily oral annatto tocotrienol at 60 mg/kg (n=8) or 100 mg/kg (n=8) plus daily subcutaneous buserelin injection (75 µg/kg) (n=8). At the end of the experiment, the rats were euthanized and their blood, tibia, and femur were harvested. Structural changes of the tibial trabecular and cortical bone were examined using X-ray micro-computed tomography. Femoral bone calcium content and biomechanical strength were also evaluated.

    Results: Annatto tocotrienol at 60 and 100 mg/kg significantly prevented the deterioration of trabecular bone and cortical thickness in buserelin-treated rats (P<0.05). Both doses of annatto tocotrienol also improved femoral biomechanical strength and bone calcium content in buserelin-treated rats (P<0.05). The effects of annatto tocotrienol were comparable to calcium supplementation.

    Conclusion: Annatto tocotrienol supplementation is effective in preventing degeneration of the bone induced by buserelin. Therefore, it is a potential antiosteoporotic agent for men receiving androgen deprivation therapy.

    Matched MeSH terms: Tocotrienols/pharmacology*
  13. Wong SK, Chin KY, Suhaimi FH, Ahmad F, Ima-Nirwana S
    Bone, 2018 11;116:8-21.
    PMID: 29990585 DOI: 10.1016/j.bone.2018.07.003
    Metabolic syndrome (MetS) is associated with osteoporosis due to the underlying inflammatory and hormonal changes. Annatto tocotrienol has been shown to improve medical complications associated with MetS or bone loss in animal studies. This study aimed to investigate the effects of annatto tocotrienol as a single treatment for MetS and osteoporosis in high-carbohydrate high-fat (HCHF) diet-induced MetS animals. Three-month-old male Wistar rats were randomly divided into five groups. The baseline group was euthanized at the onset of the study. The normal group received standard rat chow and tap water. The remaining groups received HCHF diet and treated with three different regimens orally daily: (a) tocopherol-stripped corn oil (the vehicle of tocotrienol), (b) 60 mg/kg annatto tocotrienol, and (c) 100 mg/kg annatto tocotrienol. At the end of the study, measurements of MetS parameters, body compositions, and bone mineral density were performed in animals before sacrifice. Upon euthanasia, blood and femur of the rats were harvested for the evaluations of bone microstructure, biomechanical strength, remodelling activities, hormonal changes, and inflammatory response. Treatment with annatto tocotrienol improved all MetS parameters (except abdominal obesity), trabecular bone microstructure, bone strength, increased osteoclast number, normalized hormonal changes and inflammatory response in the HCHF animals. In conclusion, annatto tocotrienol is a potential agent for managing MetS and osteoporosis concurrently. The beneficial effects of annatto tocotrienol may be attributed to its ability to prevent the hormonal changes and pro-inflammatory state in animals with MetS.
    Matched MeSH terms: Tocotrienols/pharmacology
  14. Selvaduray KR, Radhakrishnan AK, Kutty MK, Nesaretnam K
    J Interferon Cytokine Res, 2010 Dec;30(12):909-16.
    PMID: 21121862 DOI: 10.1089/jir.2010.0021
    Several mechanisms have been postulated for the anticancer effects of tocotrienols. In this study, for the first time, the anticancer effect of tocotrienols is linked to increased expression of interleukin-24 (IL-24) mRNA, a cytokine reported to have antitumor effects in many cancer models. Tocotrienol isomers (α-T3, γ-T3, and δ-T3) and tocotrienol-rich fraction (TRF) inhibited the growth of the 4T1 murine mammary cancer cells (P  γ-T3 > TRF > α-T3 > α-T, which was similar to their antiproliferative effects. The IL-24 mRNA levels in tumor tissues of BALB/c mice supplemented with TRF increased 2-fold when compared with control mice. Increased levels of IL-24 have been associated with inhibition of tumor growth and angiogenesis. Treatment of 4T1 cells with TRF and δ-T3 significantly decreased IL-8 and vascular endothelial growth factor mRNA levels. Hence, we report that tocotrienols have potent antiangiogenic and antitumor effects that is associated with increased levels of IL-24 mRNA.
    Matched MeSH terms: Tocotrienols/pharmacology*
  15. Wan Hasan WN, Abd Ghafar N, Chin KY, Ima-Nirwana S
    Drug Des Devel Ther, 2018;12:1715-1726.
    PMID: 29942115 DOI: 10.2147/DDDT.S168935
    PURPOSE: Annatto-derived tocotrienol (AnTT) has been shown to improve bone formation in animal models of osteoporosis. However, detailed studies of the effects of AnTT on preosteoblastic cells were limited. This study was conducted to investigate the osteogenic effect of AnTT on preosteoblast MC3T3-E1 cells in a time-dependent manner.

    MATERIALS AND METHODS: Murine MC3T3-E1 preosteoblastic cells were cultured in the different concentrations of AnTT (0.001-1 µg/mL) up to 24 days. Expression of osteoblastic differentiation markers was measured by qPCR (osterix [OSX], collagen 1 alpha 1 [COL1α1], alkaline phosphatase [ALP], and osteocalcin [OCN]) and by fluorometric assay for ALP activity. Detection of collagen and mineralized nodules was done via Direct Red staining and Alizarin Red staining, respectively.

    RESULTS: The results showed that osteoblastic differentiation-related genes, such as OSX, COL1α1, ALP, and OCN, were significantly increased in the AnTT-treated groups compared to the vehicle group in a time-dependent manner (P<0.05). Type 1 collagen level was increased from day 3 to day 15 in the AnTT-treated groups, while ALP activity was increased from day 9 to day 21 in the AnTT-treated groups (P<0.05). Enhanced mineralization was observed in the AnTT-treated groups via increasing Alizarin Red staining from day 3 to day 21 (P<0.05).

    CONCLUSION: Our results suggest that AnTT enhances the osteogenic activity by promoting the bone formation-related genes and proteins in a temporal and sequential manner.

    Matched MeSH terms: Tocotrienols/pharmacology*
  16. Selvaraju TR, Khaza'ai H, Vidyadaran S, Abd Mutalib MS, Vasudevan R
    Bosn J Basic Med Sci, 2014 Nov 16;14(4):195-204.
    PMID: 25428670 DOI: 10.17305/bjbms.2014.4.91
    Tocotrienol rich fraction (TRF) is an extract of palm oil, which consists of 25% alpha tocopherol (α-TCP) and 75% tocotrienols. TRF has been shown to possess potent antioxidant, anti-inflammatory, anticancer, neuroprotection, and cholesterol lowering activities. Glutamate is the main excitatory amino acid neurotransmitter in the central nervous system of mammalian, which can be excitotoxic, and it has been suggested to play a key role in neurodegenerative disorders like Parkinson's and Alzheimer's diseases. In this present study, the effects of vitamin E (TRF and α-TCP) in protecting astrocytes against glutamate injury were elucidated. Astrocytes induced with 180 mM of glutamate lead to significant cell death. However, glutamate mediated cytotoxicity was diminished via pre and post supplementation of TRF and α-TCP. Hence, vitamin E acted as a potent antioxidant agent in recovering mitochondrial injury due to elevated oxidative stress, and enhanced better survivability upon glutamate toxicity.
    Matched MeSH terms: Tocotrienols/pharmacology*
  17. Chin KY, Abdul-Majeed S, Fozi NF, Ima-Nirwana S
    Nutrients, 2014 Nov;6(11):4974-83.
    PMID: 25389899 DOI: 10.3390/nu6114974
    This study aimed to evaluate the effects of annatto tocotrienol on indices of bone static histomorphometry in orchidectomized rats. Forty male rats were randomized into baseline (BL), sham (SH), orchidectomized (ORX), annatto tocotrienol-treated (AnTT) and testosterone enanthate-treated (TE) groups. The BL group was sacrificed upon receipt. All rats except the SH group underwent bilateral orchidectomy. Annatto tocotrienol at 60 mg/kg body weight was administered orally daily to the AnTT group for eight weeks. Testosterone enanthate at 7 mg/kg body weight was administered intramuscularly once weekly for eight weeks to the TE group. The rat femurs were collected for static histomorphometric analysis upon necropsy. The results indicated that the ORX group had significantly higher osteoclast surface and eroded surface, and significantly lower osteoblast surface, osteoid surface and osteoid volume compared to the SH group (p < 0.05). Annatto tocotrienol and testosterone enanthate intervention prevented all these changes (p < 0.05). The efficacy of annatto tocotrienol was on par with testosterone enanthate. In conclusion, annatto tocotrienol at 60 mg/kg can prevent the imbalance in bone remodeling caused by increased osteoclast and bone resorption, and decreased osteoblast and bone formation. This serves as a basis for the application of annatto tocotrienol in hypogonadal men as an antiosteoporotic agent.
    Matched MeSH terms: Tocotrienols/pharmacology*
  18. Chin KY, Ima-Nirwana S
    Clin Interv Aging, 2014;9:1247-59.
    PMID: 25120355 DOI: 10.2147/CIA.S67016
    BACKGROUND: Previous animal models have demonstrated that tocotrienol is a potential treatment for postmenopausal osteoporosis. This study evaluated the antiosteoporotic effects of annatto-derived tocotrienol (AnTT) using a testosterone-deficient osteoporotic rat model.
    METHODS: Forty rats were divided randomly into baseline, sham, orchidectomized, AnTT, and testosterone groups. The baseline group was euthanized without undergoing any surgical treatment or intervention. The remaining groups underwent orchidectomy, with the exception of the sham group. AnTT 60 mg/kg/day was given orally to the AnTT group, while the testosterone group received testosterone enanthate 7 mg/kg per week intramuscularly for 8 weeks. Structural changes in trabecular bone at the proximal tibia were examined using microcomputed tomography. Structural and dynamic changes at the distal femur were examined using histomorphometric methods. Serum osteocalcin and C-terminal of type 1 collagen crosslinks were measured. Bone-related gene expression in the distal femur was examined.
    RESULTS: There were significant degenerative changes in structural indices in the orchidectomized group (P<0.05), but no significant changes in dynamic indices, bone remodeling markers, or gene expression (P>0.05) when compared with the sham group. The AnTT group showed significant improvement in structural indices at the femur (P<0.05) and significantly increased expression of bone formation genes (P<0.05). Testosterone was more effective than AnTT in preventing degeneration of bone structural indices in the femur and tibia (P<0.05).
    CONCLUSION: AnTT supplementation improves bone health in testosterone-deficient rats by enhancing bone formation. Its potential should be evaluated further by varying the dosage and treatment duration.
    KEYWORDS: bone remodeling; osteoporosis; testosterone; tocotrienol
    Matched MeSH terms: Tocotrienols/pharmacology*
  19. Khee SG, Yusof YA, Makpol S
    Oxid Med Cell Longev, 2014;2014:725929.
    PMID: 25132913 DOI: 10.1155/2014/725929
    Emerging evidences highlight the implication of microRNAs as a posttranscriptional regulator in aging. Several senescence-associated microRNAs (SA-miRNAs) are found to be differentially expressed during cellular senescence. However, the role of dietary compounds on SA-miRNAs remains elusive. This study aimed to elucidate the modulatory role of tocotrienol-rich fraction (TRF) on SA-miRNAs (miR-20a, miR-24, miR-34a, miR-106a, and miR-449a) and established target genes of miR-34a (CCND1, CDK4, and SIRT1) during replicative senescence of human diploid fibroblasts (HDFs). Primary cultures of HDFs at young and senescent were incubated with TRF at 0.5 mg/mL. Taqman microRNA assay showed significant upregulation of miR-24 and miR-34a and downregulation of miR-20a and miR-449a in senescent HDFs (P < 0.05). TRF reduced miR-34a expression in senescent HDFs and increased miR-20a expression in young HDFs and increased miR-449a expression in both young and senescent HDFs. Our results also demonstrated that ectopic expression of miR-34a reduced the expression of CDK4 significantly (P < 0.05). TRF inhibited miR-34a expression thus relieved its inhibition on CDK4 gene expression. No significant change was observed on the expression of CCND1, SIRT1, and miR-34a upstream transcriptional regulator, TP53. In conclusion tocotrienol-rich fraction prevented cellular senescence of human diploid fibroblasts via modulation of SA-miRNAs and target genes expression.
    Matched MeSH terms: Tocotrienols/pharmacology*
  20. 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: Tocotrienols/pharmacology*
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