MyMedR

Displaying publications 121 - 140 of 210 in total

Abstract:

Sort:

Fulltext Tocotrienol-rich fraction prevents cell cycle arrest and elongates telomere length in senescent human diploid fibroblasts

Makpol S, Durani LW, Chua KH, Mohd Yusof YA, Ngah WZ

J Biomed Biotechnol, 2011;2011:506171.
PMID: 21541185 DOI: 10.1155/2011/506171

This study determined the molecular mechanisms of tocotrienol-rich fraction (TRF) in preventing cellular senescence of human diploid fibroblasts (HDFs). Primary culture of HDFs at various passages were incubated with 0.5 mg/mL TRF for 24 h. Telomere shortening with decreased telomerase activity was observed in senescent HDFs while the levels of damaged DNA and number of cells in G(0)/G(1) phase were increased and S phase cells were decreased. Incubation with TRF reversed the morphology of senescent HDFs to resemble that of young cells with decreased activity of SA-β-gal, damaged DNA, and cells in G(0)/G(1) phase while cells in the S phase were increased. Elongated telomere length and restoration of telomerase activity were observed in TRF-treated senescent HDFs. These findings confirmed the ability of tocotrienol-rich fraction in preventing HDFs cellular ageing by restoring telomere length and telomerase activity, reducing damaged DNA, and reversing cell cycle arrest associated with senescence.

Matched MeSH terms: Tocotrienols/pharmacology*
Fulltext Perturbation of cellular immune functions in cigarette smokers and protection by palm oil vitamin E supplementation

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: Tocotrienols/administration & dosage; Tocotrienols/blood
Fulltext Gamma-tocotrienol treatment increased peroxiredoxin-4 expression in HepG2 liver cancer cell line

Abdul Rahman Sazli F, Jubri Z, Abdul Rahman M, Karsani SA, Md Top AG, Wan Ngah WZ

BMC Complement Altern Med, 2015;15:64.
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*; Tocotrienols/therapeutic use
Fulltext Comparative effects of a tocotrienol-rich fraction and tocopherol in aspirin-induced gastric lesions in rats

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/administration & dosage*; Tocotrienols/pharmacology
Palm tocotrienol-rich fraction reduced plasma homocysteine and heart oxidative stress in rats fed with a high-methionine diet

Norsidah KZ, Asmadi AY, Azizi A, Faizah O, Kamisah Y

J Physiol Biochem, 2013 Sep;69(3):441-9.
PMID: 23208529 DOI: 10.1007/s13105-012-0226-3

Oxidative stress contributes to cardiovascular diseases. We aimed to study the effects of palm tocotrienol-rich fraction (TRF) on plasma homocysteine and cardiac oxidative stress in rats fed with a high-methionine diet. Forty-two male Wistar rats were divided into six groups. The first group was the control. Groups 2-6 were fed 1% methionine diet for 10 weeks. From week 6 onward, folate (8 mg/kg diet) or palm TRF (30, 60 and 150 mg/kg diet) was added into the diet of groups 3, 4, 5 and 6. The rats were then killed. Palm TRF at 150 mg/kg and folate supplementation prevented the increase in plasma total homocysteine (4.14 ± 0.33 and 4.30 ± 0.26 vs 5.49 ± 0.25 mmol/L, p < 0.05) induced by a high-methionine diet. The increased heart thiobarbituric acid reactive substance in rats fed with high-methionine diet was also prevented by the supplementations of palm TRF (60 and 150 mg/kg) and folate. The high-methionine group had a lower glutathione peroxidase activity (49 ± 3 vs 69 ± 4 pmol/mg protein/min) than the control group. This reduction was reversed by palm TRF at 60 and 150 mg/kg diet (p < 0.05), but not by folate. Catalase and superoxide dismutase activities were unaffected by both methionine and vitamin supplementations. In conclusion, palm TRF was comparable to folate in reducing high-methionine diet-induced hyperhomocysteinemia and oxidative stress in the rats' hearts. However, palm TRF was more effective than folate in preserving the heart glutathione peroxidase enzyme activity.

Matched MeSH terms: Tocotrienols/administration & dosage*; Tocotrienols/isolation & purification
Fulltext Synthesis of [18F]F-γ-T-3, a Redox-Silent γ-Tocotrienol (γ-T-3) Vitamin E Analogue for Image-Based In Vivo Studies of Vitamin E Biodistribution and Dynamics

Roselt P, Cullinane C, Noonan W, Elsaidi H, Eu P, Wiebe LI

Molecules, 2020 Dec 03;25(23).
PMID: 33287202 DOI: 10.3390/molecules25235700

Vitamin E, a natural antioxidant, is of interest to scientists, health care pundits and faddists; its nutritional and biomedical attributes may be validated, anecdotal or fantasy. Vitamin E is a mixture of tocopherols (TPs) and tocotrienols (T-3s), each class having four substitutional isomers (α-, β-, γ-, δ-). Vitamin E analogues attain only low concentrations in most tissues, necessitating exacting invasive techniques for analytical research. Quantitative positron emission tomography (PET) with an F-18-labeled molecular probe would expedite access to Vitamin E's biodistributions and pharmacokinetics via non-invasive temporal imaging. (R)-6-(3-[18F]Fluoropropoxy)-2,7,8-trimethyl-2-(4,8,12-trimethyltrideca-3,7,11-trien-1-yl)-chromane ([18F]F-γ-T-3) was prepared for this purpose. [18F]F-γ-T-3 was synthesized from γ-T-3 in two steps: (i) 1,3-di-O-tosylpropane was introduced at C6-O to form TsO-γ-T-3, and (ii) reaction of this tosylate with [18F]fluoride in DMF/K222. Non-radioactive F-γ-T-3 was synthesized by reaction of γ-T-3 with 3-fluoropropyl methanesulfonate. [18F]F-γ-T-3 biodistribution in a murine tumor model was imaged using a small-animal PET scanner. F-γ-T-3 was prepared in 61% chemical yield. [18F]F-γ-T-3 was synthesized in acceptable radiochemical yield (RCY 12%) with high radiochemical purity (>99% RCP) in 45 min. Preliminary F-18 PET images in mice showed upper abdominal accumulation with evidence of renal clearance, only low concentrations in the thorax (lung/heart) and head, and rapid clearance from blood. [18F]F-γ-T-3 shows promise as an F-18 PET tracer for detailed in vivo studies of Vitamin E. The labeling procedure provides acceptable RCY, high RCP and pertinence to all eight Vitamin E analogues.

Matched MeSH terms: Tocotrienols/pharmacokinetics*; Tocotrienols/chemistry*
Fulltext Comparison between tocotrienol and omeprazole on gastric growth factors in stress-exposed rats

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*; Tocotrienols/therapeutic use
Fulltext A Review on the Relationship between Tocotrienol and Alzheimer Disease

Chin KY, Tay SS

Nutrients, 2018 Jul 09;10(7).
PMID: 29987193 DOI: 10.3390/nu10070881

Alzheimer’s disease (AD) is plaguing the aging population worldwide due to its tremendous health care and socioeconomic burden. Current treatment of AD only offers symptomatic relief to patients. Development of agents targeting specific pathologies of AD is very slow. Tocotrienol, a member of the vitamin E family, can tackle many aspects of AD, such as oxidative stress, mitochondrial dysfunction and abnormal cholesterol synthesis. This review summarizes the current evidence on the role of tocotrienol as a neuroprotective agent. Preclinical studies showed that tocotrienol could reduce oxidative stress by acting as a free-radical scavenger and promoter of mitochondrial function and cellular repair. It also prevented glutamate-induced neurotoxicity in the cells. Human epidemiological studies showed a significant inverse relationship between tocotrienol levels and the occurrence of AD. However, there is no clinical trial to support the claim that tocotrienol can delay or prevent the onset of AD. As a conclusion, tocotrienol has the potential to be developed as an AD-preventing agent but further studies are required to validate its efficacy in humans.

Matched MeSH terms: Tocotrienols/adverse effects; Tocotrienols/therapeutic use*
Fulltext Tocotrienol-Rich Vitamin E from Palm Oil (Tocovid) and Its Effects in Diabetes and Diabetic Nephropathy: A Pilot Phase II Clinical Trial

Tan SMQ, Chiew Y, Ahmad B, Kadir KA

Nutrients, 2018 Sep 17;10(9).
PMID: 30227659 DOI: 10.3390/nu10091315

Tocotrienol-rich vitamin E from palm oil (Tocovid) has been shown to ameliorate diabetes through its superior antioxidant, antihyperglycemic, and anti-inflammatory properties in diabetic rats. This study aimed to investigate the effects of Tocovid on diabetic nephropathy in patients with type 2 diabetes. Baseline parameters of potential subjects such as HbA1c, blood pressure, Advanced Glycation Endproduct (AGE), soluble receptor for AGE (sRAGE), Nε-Carboxymethyllysine (Nε-CML), and Cystatin C were assessed for possible correlation with diabetic nephropathy. Only subjects with diabetic nephropathy or urine microalbuminuria-positive defined as Urine Albumin to Creatinine Ratio (UACR) >10 mg/mmol were recruited into a prospective, randomized, double-blinded, placebo-controlled trial. The intervention group (n = 22) received Tocovid 200 mg twice a day while the control group (n = 23) received placebo twice a day for 8 weeks. Changes in Hemoglobin A1c (HbA1c), blood pressure, serum biomarkers and renal parameters such as UACR, serum creatinine, and estimated Glomerular Filtration Rate (eGFR) were compared between the two groups. It was found that serum Nε-CML significantly correlated to the severity of microalbuminuria. For every 1 ng/mL increase in serum Nε-CML, the odds of diabetic nephropathy increased by 1.476 times. Tocovid, compared to placebo, significantly reduced serum creatinine but not eGFR, UACR, HbA1c, blood pressure, and serum biomarkers. In conclusion, serum Nε-CML is a potential biomarker for diabetic nephropathy. Treatment with Tocovid significantly reduced serum creatinine; therefore Tocovid may be a useful addition to the current treatment for diabetic nephropathy.

Matched MeSH terms: Tocotrienols/adverse effects; Tocotrienols/therapeutic use*
Palm tocotrienols inhibit proliferation of murine mammary cancer cells and induce expression of interleukin-24 mRNA

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*; Tocotrienols/chemistry
Fulltext Annatto-derived tocotrienol stimulates osteogenic activity in preosteoblastic MC3T3-E1 cells: a temporal sequential study

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/isolation & purification; Tocotrienols/pharmacology*
Fulltext The neuroprotective effects of tocotrienol rich fraction and alpha tocopherol against glutamate injury in astrocytes

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*
Fulltext Annatto tocotrienol improves indices of bone static histomorphometry in osteoporosis due to testosterone deficiency in rats

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*
Fulltext Effects of annatto-derived tocotrienol supplementation on osteoporosis induced by testosterone deficiency in rats

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*
Fulltext Expression of senescence-associated microRNAs and target genes in cellular aging and modulation by tocotrienol-rich fraction

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*
Fulltext Comparative effects of biodynes, tocotrienol-rich fraction, and tocopherol in enhancing collagen synthesis and inhibiting collagen degradation in stress-induced premature senescence model of human diploid fibroblasts

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*
Tocotrienol-treated MCF-7 human breast cancer cells show down-regulation of API5 and up-regulation of MIG6 genes

Ramdas P, Rajihuzzaman M, Veerasenan SD, Selvaduray KR, Nesaretnam K, Radhakrishnan AK

Cancer Genomics Proteomics, 2011 Jan-Feb;8(1):19-31.
PMID: 21289334

Tocotrienols belong to the vitamin E family and have multiple anticancer effects, such as antiproliferative, antioxidant, pro-apoptosis and antimetastatic. This study aimed to identify the genes that are regulated in human breast cancer cells following exposure to various isomers of vitamin E as these may be potential targets for the treatment of breast cancer.

Matched MeSH terms: Tocotrienols/pharmacology*
Suppression of tumor growth by palm tocotrienols via the attenuation of angiogenesis

Weng-Yew W, Selvaduray KR, Ming CH, Nesaretnam K

Nutr Cancer, 2009;61(3):367-73.
PMID: 19373610 DOI: 10.1080/01635580802582736

Previous studies have revealed that tocotrienol-rich fractions (TRF) from palm oil inhibit the proliferation and the growth of solid tumors. The anticancer activity of TRF is said to be caused by several mechanisms, one of which is antiangiogenesis. In this study, we looked at the antiangiogenic effects of TRF. In vitro investigations of the antiangiogenic activities of TRF, delta-tocotrienol (deltaT3), and alpha-tocopherol (alphaToc) were carried out in human umbilical vein endothelial cells (HUVEC). TRF and deltaT3 significantly inhibited cell proliferation from 4 microg/ml onward (P < 0.05). Cell migration was inhibited the most by deltaT3 at 12 microg/ml. Anti-angiogenic properties of TRF were carried out further in vivo using the chick embryo chorioallantoic membrane (CAM) assay and BALB/c mice model. TRF at 200 microg/ml reduced the vascular network on CAM. TRF treatment of 1 mg/mouse significantly reduced 4T1 tumor volume in BALB/c mice. TRF significantly reduced serum vascular endothelial growth factor (VEGF) level in BALB/c mice. In conclusion, this study showed that palm tocotrienols exhibit anti-angiogenic properties that may assist in tumor regression.

Matched MeSH terms: Tocotrienols/pharmacology*
Fulltext Tocotrienol and alpha-tocopherol reduce corticosterone and noradrenalin levels in rats exposed to restraint stress

Nur Azlina MF, Nafeeza MI

Pharmazie, 2008 Dec;63(12):890-2.
PMID: 19177905

This study investigates the effects of tocotrienol (TT) or alpha-tocopherol (TF) supplementation on corticosterone level, noradrenalin level and gastric lesions in rats exposed to restraint stress. Twenty-four male Sprague Dawley rats were randomly assigned into 4 equally sized groups; two control groups were given olive oil, while the treated group was supplemented with either tocotrienol of tocopherol orally at a dose of 60 mg/kg body weight. After 28 days of treatment, one control group, TT group and TF group were subjected to restraint stress, 2 hours daily for 4 consecutive days. After the last exposure to stress, plasma samples were taken to determine the corticosterone and noradrenalin levels, after which the rats were sacrificed. The stomach was excised for the evaluation of gastric lesions. Our findings showed that TT and TF were able to maintain the corticosterone level to the prestress values, while only TT was able to maintain the noradrenalin level in rats exposed to stress. Tocotrienol was found to be better in preventing formation of gastric lesions compared to TF. As a conclusion, the protective effect of vitamin E was related to the ability to inhibit stress induced elevation of corticosterone and noradrenalin levels.

Matched MeSH terms: Tocotrienols/pharmacology*
Reduction of DNA damage in older healthy adults by Tri E Tocotrienol supplementation

Chin SF, Hamid NA, Latiff AA, Zakaria Z, Mazlan M, Yusof YA, et al.

Nutrition, 2008 Jan;24(1):1-10.
PMID: 17884341

The free radical theory of aging (FRTA) suggests that free radicals are the leading cause of deteriorating physiologic function during senescence. Free radicals attack cellular structures or molecules such as DNA resulting in various modifications to the DNA structures. Accumulation of unrepaired DNA contributes to a variety of disorders associated with the aging process.

Matched MeSH terms: Tocotrienols/pharmacology*

Filters

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links