MyMedR

Displaying all 17 publications

Abstract:

Sort:

Fulltext Pharmacology and Pharmacokinetics of Vitamin E: Nanoformulations to Enhance Bioavailability

Mohd Zaffarin AS, Ng SF, Ng MH, Hassan H, Alias E

Int J Nanomedicine, 2020;15:9961-9974.
PMID: 33324057 DOI: 10.2147/IJN.S276355

Vitamin E belongs to the family of lipid-soluble vitamins and can be divided into two groups, tocopherols and tocotrienols, with four isomers (alpha, beta, gamma and delta). Although vitamin E is widely known as a potent antioxidant, studies have also revealed that vitamin E possesses anti-inflammatory properties. These crucial properties of vitamin E are beneficial in various aspects of health, especially in neuroprotection and cardiovascular, skin and bone health. However, the poor bioavailability of vitamin E, especially tocotrienols, remains a great limitation for clinical applications. Recently, nanoformulations that include nanovesicles, solid-lipid nanoparticles, nanostructured lipid carriers, nanoemulsions, and polymeric nanoparticles have shown promising outcomes in improving the efficacy and bioavailability of vitamin E. This review focuses on the pharmacological properties and pharmacokinetics of vitamin E and current advances in vitamin E nanoformulations for future clinical applications. The limitations and future recommendations are also discussed in this review.

Matched MeSH terms: Vitamin E/chemistry
Recent advances in TPGS-based nanoparticles of docetaxel for improved chemotherapy

Choudhury H, Gorain B, Pandey M, Kumbhar SA, Tekade RK, Iyer AK, et al.

Int J Pharm, 2017 Aug 30;529(1-2):506-522.
PMID: 28711640 DOI: 10.1016/j.ijpharm.2017.07.018

Docetaxel (DTX) is one of the important antitumor drugs, being used in several common chemotherapies to control leading cancer types. Severe toxicities of the DTX are prominent due to sudden parenteral exposure of desired loading dose to maintain the therapeutic concentration. Field of nanotechnology is leading to resist sudden systemic exposure of DTX with more specific delivery to the site of cancer. Further nanometric size range of the formulation aid for prolonged circulation, thereby extensive exposure results better efficacy. In this article, we extensively reviewed the therapeutic benefit of incorporating d-α-tocopheryl polyethylene glycol 1000 succinate (vitamin E TPGS, or simply TPGS) in the nanoparticle (NP) formulation of DTX for improved delivery, tumor control and tolerability. TPGS is well accepted nonionic-ampiphilic polymer which has been identified in the role of emulsifier, stabilizer, penetration enhancer, solubilizer and in protection in micelle. Simultaneously, P-glycoprotein inhibitory activity of TPGS in the multidrug resistant (MDR) cancer cells along with its apoptotic potential are the added advantage of TPGS to be incorporated in nano-chemotherapeutics. Thus, it could be concluded that TPGS based nanoparticulate application is an advanced approach to improve therapeutic efficacy of chemotherapeutic agents by better internalization and sustained retention of the NPs.

Matched MeSH terms: Vitamin E/chemistry*
Fulltext Chromatographic Separation of Vitamin E Enantiomers

Fu JY, Htar TT, De Silva L, Tan DM, Chuah LH

Molecules, 2017 Feb 04;22(2).
PMID: 28165404 DOI: 10.3390/molecules22020233

Vitamin E is recognized as an essential vitamin since its discovery in 1922. Most vegetable oils contain a mixture of tocopherols and tocotrienols in the vitamin E composition. Structurally, tocopherols and tocotrienols share a similar chromanol ring and a side chain at the C-2 position. Owing to the three chiral centers in tocopherols, they can appear as eight different stereoisomers. Plant sources of tocopherol are naturally occurring in the form of RRR while synthetic tocopherols are usually in the form of all-racemic mixture. Similarly, with only one chiral center, natural tocotrienols occur as the R-isoform. In this review, we aim to discuss a few chromatographic methods that had been used to separate the stereoisomers of tocopherols and tocotrienols. These methods include high performance liquid chromatography, gas chromatography and combination of both. The review will focus on method development including selection of chiral columns, detection method and choice of elution solvent in the context of separation efficiency, resolution and chiral purity. The applications for separation of enantiomers in vitamin E will also be discussed especially in terms of the distinctive biological potency among the stereoisoforms.

Matched MeSH terms: Vitamin E/chemistry*
Application of supercritical fluid chromatography in the quantitative analysis of minor components (carotenes, vitamin E, sterols, and squalene) from palm oil

Choo YM, Ng MH, Ma AN, Chuah CH, Hashim MA

Lipids, 2005 Apr;40(4):429-32.
PMID: 16028723

The application of supercritical fluid chromatography (SFC) coupled with a UV variable-wavelength detector to isolate the minor components (carotenes, vitamin E, sterols, and squalene) in crude palm oil (CPO) and the residual oil from palm-pressed fiber is reported. SFC is a good technique for the isolation and analysis of these compounds from the sources mentioned. The carotenes, vitamin E, sterols, and squalene were isolated in less than 20 min. The individual vitamin E isomers present in palm oil were also isolated into their respective components, alpha-tocopherol, alpha-tocotrienol, gamma-tocopherol, gamma-tocotrienol, and delta-tocotrienol. Calibration of all the minor components of palm as well as the individual components of palm vitamin E was carried out and was found to be comparable to those analyzed by other established analytical methods.

Matched MeSH terms: Vitamin E/chemistry
In Silico Docking of Vitamin E Isomers on Transport Proteins

Zulkiflee NS, Awang SA, Ming WX, Kamilan MFW, Mariappan MY, Kit TJ

Curr Comput Aided Drug Des, 2020;16(4):467-472.
PMID: 31203808 DOI: 10.2174/1573409915666190614113733

BACKGROUND: Vitamin E is comprised of α, β, γ and δ-tocopherols (Ts) and α, β, γ and δ- tocotrienols (T3s). Vitamin E has neuroprotective antioxidant, anti-cancer, and cholesterol-lowering effects. Intracellular trafficking of these isomers remains largely unknown, except for αT which is selectively transported by αT transfer protein (αTTP).
OBJECTIVE: This study aimed to determine the binding of vitamin E isomers on transport proteins using in silico docking.
METHODS: Transport proteins were selected using AmiGo Gene Ontology tool based on the same molecular function annotation as αTTP. Protein structures were obtained from the Protein Data Bank. Ligands structures were obtained from ZINC database. In silico docking was performed using SwissDock.
RESULTS AND DISCUSSION: A total of 6 transport proteins were found: SEC14-like protein 2, glycolipid transfer protein (GLTP), pleckstrin homology domain-containing family A member 8, collagen type IV alpha-3-binding protein, ceramide-1-phosphate transfer protein and afamin. Compared with other transport proteins, αTTP had the highest affinities for all isomers except βT3. Binding order of vitamin E isomers toward αTTP was γT > βT > αT > δT > αT3 > γT3 > δT3 > βT3. GLTP had a higher affinity for tocotrienols than tocopherols. βT3 bound stronger to GLTP than αTTP.
CONCLUSION: αTTP remained as the most preferred transport protein for most of the isomers. The binding affinity of αT toward αTTP was not the highest than other isomers suggested that other intracellular trafficking mechanisms of these isomers may exist. GLTP may mediate the intracellular transport of tocotrienols, especially βT3. Improving the bioavailability of these isomers may enhance their beneficial effects to human.

Matched MeSH terms: Vitamin E/chemistry
Stability of Bioactive Compounds and Antioxidant Activities of Kenaf Seed Oil-in-Water Nanoemulsions under Different Storage Temperatures

Cheong AM, Tan CP, Nyam KL

J Food Sci, 2018 Oct;83(10):2457-2465.
PMID: 30178877 DOI: 10.1111/1750-3841.14332

Kenaf seed oil-in-water nanoemulsions (NANO) stabilized by sodium caseinate (SC), beta-cyclodextrin (β-CD), and Tween 20 (T20) have been optimized and shown to improve in vitro bioaccessibility and physicochemical stability in the previous study. The main objective of this study was to evaluate the stability of bioactive compounds and antioxidants in the NANO during storage at different temperatures (4 °C, 25 °C, and 40 °C). An evaluation of the antioxidant activities of each emulsifier showed that SC had good scavenging capability with 97.6% ABTS radical scavenging activity. Therefore, SC which was used as one of the main emulsifiers could further enhanced the antioxidant activity of NANO. At week 8 of storage, NANO that stored at 4 °C had maintained the best bioactive compounds stability and antioxidant activities with 90% retention of vitamin E and 65% retention of phytosterols. These results suggested that 4 °C would be the most suitable storage temperature for NANO containing naturally present vitamin E and phytosterols. From the accelerated storage results at 40 °C, NANO containing vitamin E and phytosterols had maintained half of its initial concentration until week 4 and week 2 of storage, which is equivalent to 16 weeks and 8 weeks of storage at room temperature, respectively.
PRACTICAL APPLICATION: The results of this study provide a better understanding on the stability of bioactive compounds and antioxidant activities in oil-in-water nanoemulsions that stabilized by similar ternary emulsifiers during storage at different temperatures. In addition, this study could be used as a predictive model to estimate the shelf life of bioactive compounds encapsulated in the form of nanoemulsions.

Matched MeSH terms: Vitamin E/chemistry
Fulltext Synergistic effect of pH-responsive folate-functionalized poloxamer 407-TPGS-mixed micelles on targeted delivery of anticancer drugs

Butt AM, Mohd Amin MC, Katas H

Int J Nanomedicine, 2015;10:1321-34.
PMID: 25709451 DOI: 10.2147/IJN.S78438

BACKGROUND: Doxorubicin (DOX), an anthracycline anticancer antibiotic, is used for treating various types of cancers. However, its use is associated with toxicity to normal cells and development of resistance due to overexpression of drug efflux pumps. Poloxamer 407 (P407) and vitamin E TPGS (D-α-tocopheryl polyethylene glycol succinate, TPGS) are widely used polymers as drug delivery carriers and excipients for enhancing the drug retention times and stability. TPGS reduces multidrug resistance, induces apoptosis, and shows selective anticancer activity against tumor cells. Keeping in view the problems, we designed a mixed micelle system encapsulating DOX comprising TPGS for its selective anticancer activity and P407 conjugated with folic acid (FA) for folate-mediated receptor targeting to cancer cells.
METHODS: FA-functionalized P407 was prepared by carbodiimide crosslinker chemistry. P407-TPGS/FA-P407-TPGS-mixed micelles were prepared by thin-film hydration method. Cytotoxicity of blank micelles, DOX, and DOX-loaded micelles was determined by alamarBlue(®) assay.
RESULTS: The size of micelles was less than 200 nm with encapsulation efficiency of 85% and 73% for P407-TPGS and FA-P407-TPGS micelles, respectively. Intracellular trafficking study using nile red-loaded micelles indicated improved drug uptake and perinuclear drug localization. The micelles show minimal toxicity to normal human cell line WRL-68, enhanced cellular uptake of DOX, reduced drug efflux, increased DOX-DNA binding in SKOV3 and DOX-resistant SKOV3 human ovarian carcinoma cell lines, and enhanced in vitro cytotoxicity as compared to free DOX.
CONCLUSION: FA-P407-TPGS-DOX micelles show potential as a targeted nano-drug delivery system for DOX due to their multiple synergistic factors of selective anticancer activity, inhibition of multidrug resistance, and folate-mediated selective uptake.

Matched MeSH terms: Vitamin E/chemistry
Fulltext Supplementation with natural forms of vitamin E augments antigen-specific TH1-type immune response to tetanus toxoid

Radhakrishnan AK, Mahalingam D, Selvaduray KR, Nesaretnam K

Biomed Res Int, 2013;2013:782067.
PMID: 23936847 DOI: 10.1155/2013/782067

This study compared the ability of three forms of vitamin E [tocotrienol-rich fraction (TRF), alpha-tocopherol (α-T), and delta-tocotrienol (δ-T3)] to enhance immune response to tetanus toxoid (TT) immunisation in a mouse model. Twenty BALB/c mice were divided into four groups of five mice each. The mice were fed with the different forms of vitamin E (1 mg) or vehicle daily for two weeks before they were given the TT vaccine [4 Lf] intramuscularly (i.m.). Booster vaccinations were given on days 28 and 42. Serum was collected (days 0, 28, and 56) to quantify anti-TT levels. At autopsy, splenocytes harvested were cultured with TT or mitogens. The production of anti-TT antibodies was augmented (P < 0.05) in mice that were fed with δ-T3 or TRF compared to controls. The production of IFN-γ and IL-4 by splenocytes from the vitamin E treated mice was significantly (P < 0.05) higher than that from controls. The IFN-γ production was the highest in animals supplemented with δ-T3 followed by TRF and finally α-T. Production of TNF-α was suppressed in the vitamin E treated group compared to vehicle-supplemented controls. Supplementation with δ-T3 or TRF can enhance immune response to TT immunisation and production of cytokines that promote cell-mediated (TH1) immune response.

Matched MeSH terms: Vitamin E/chemistry
Free radical scavenging activity of conjugated linoleic acid as single or mixed isomers

Ali YM, Kadir AA, Ahmad Z, Yaakub H, Zakaria ZA, Abdullah MN

Pharm Biol, 2012 Jun;50(6):712-9.
PMID: 22181061 DOI: 10.3109/13880209.2011.621714

Conjugated linoleic acids (CLAs) are a mixture of positional and geometric isomers of linoleic acid (LA) and believed to have many positive biological activities.

Matched MeSH terms: Vitamin E/chemistry
Molecular Understanding of the Cardiomodulation in Myocardial Infarction and the Mechanism of Vitamin E Protections

Zarkasi KA, Jen-Kit T, Jubri Z

Mini Rev Med Chem, 2019;19(17):1407-1426.
PMID: 30706809 DOI: 10.2174/1389557519666190130164334

Myocardial infarction is a major cause of deaths globally. Modulation of several molecular mechanisms occurs during the initial stages of myocardial ischemia prior to permanent cardiac tissue damage, which involves both pathogenic as well as survival pathways in the cardiomyocyte. Currently, there is increasing evidence regarding the cardioprotective role of vitamin E in alleviating the disease. This fat-soluble vitamin does not only act as a powerful antioxidant; but it also has the ability to regulate several intracellular signalling pathways including HIF-1, PPAR-γ, Nrf-2, and NF-κB that influence the expression of a number of genes and their protein products. Essentially, it inhibits the molecular progression of tissue damage and preserves myocardial tissue viability. This review aims to summarize the molecular understanding of the cardiomodulation in myocardial infarction as well as the mechanism of vitamin E protection.

Matched MeSH terms: Vitamin E/chemistry
Fulltext The Effects of Vitamin E from Elaeis guineensis (Oil Palm) in a Rat Model of Bone Loss Due to Metabolic Syndrome

Wong SK, Chin KY, Suhaimi FH, Ahmad F, Ima-Nirwana S

Int J Environ Res Public Health, 2018 08 24;15(9).
PMID: 30149518 DOI: 10.3390/ijerph15091828

The beneficial effects of vitamin E in improving components of MetS or bone loss have been established. This study aimed to investigate the potential of palm vitamin E (PVE) as a single agent, targeting MetS and bone loss concurrently, using a MetS animal model. Twelve-week-old male Wistar rats were divided into five groups. The baseline group was sacrificed upon arrival. The normal group was given standard rat chow. The remaining three groups were fed with high-carbohydrate high-fat (HCHF) diet and treated with tocopherol-stripped corn oil (vehicle), 60 mg/kg or 100 mg/kg PVE. At the end of the study, the rats were evaluated for MetS parameters and bone density. After euthanasia, blood and femurs were harvested for the evaluation of lipid profile, bone histomorphometric analysis, and remodeling markers. PVE improved blood pressure, glycemic status, and lipid profile; increased osteoblast surface, osteoid surface, bone volume, and trabecular thickness, as well as decreased eroded surface and single-labeled surface. Administration of PVE also significantly reduced leptin level in the HCHF rats. PVE is a potential agent in concurrently preventing MetS and protecting bone loss. This may be, in part, achieved by reducing the leptin level and modulating the bone remodeling activity in male rats.

Matched MeSH terms: Vitamin E/chemistry
Fulltext The Molecular Mechanism of Vitamin E as a Bone-Protecting Agent: A Review on Current Evidence

Wong SK, Mohamad NV, Ibrahim N', Chin KY, Shuid AN, Ima-Nirwana S

Int J Mol Sci, 2019 Mar 22;20(6).
PMID: 30909398 DOI: 10.3390/ijms20061453

Bone remodelling is a tightly-coordinated and lifelong process of replacing old damaged bone with newly-synthesized healthy bone. In the bone remodelling cycle, bone resorption is coupled with bone formation to maintain the bone volume and microarchitecture. This process is a result of communication between bone cells (osteoclasts, osteoblasts, and osteocytes) with paracrine and endocrine regulators, such as cytokines, reactive oxygen species, growth factors, and hormones. The essential signalling pathways responsible for osteoclastic bone resorption and osteoblastic bone formation include the receptor activator of nuclear factor kappa-B (RANK)/receptor activator of nuclear factor kappa-B ligand (RANKL)/osteoprotegerin (OPG), Wnt/β-catenin, and oxidative stress signalling. The imbalance between bone formation and degradation, in favour of resorption, leads to the occurrence of osteoporosis. Intriguingly, vitamin E has been extensively reported for its anti-osteoporotic properties using various male and female animal models. Thus, understanding the underlying cellular and molecular mechanisms contributing to the skeletal action of vitamin E is vital to promote its use as a potential bone-protecting agent. This review aims to summarize the current evidence elucidating the molecular actions of vitamin E in regulating the bone remodelling cycle.

Matched MeSH terms: Vitamin E/chemistry*
Fulltext The Effect of Pressure and Solvent on the Supercritical Fluid Chromatography Separation of Tocol Analogs in Palm Oil

Ng MH, Kushairi A

Molecules, 2017 Aug 29;22(9).
PMID: 28850073 DOI: 10.3390/molecules22091424

There are six tocol analogs present in palm oil, namely α-tocopherol (α-T), α-tocomonoenol (α-T₁), α-tocotrienol (α-T₃), γ-tocotrienol (γ-T₃), β-tocotrioenol (β-T₃) and δ-tocotrienol (δ-T₃). These analogs were difficult to separate chromatographically due to their similar structures, physical and chemical properties. This paper reports on the effect of pressure and injection solvent on the separation of the tocol analogs in palm oil. Supercritical CO₂ modified with ethanol was used as the mobile phase. Both total elution time and resolution of the tocol analogs decreased with increased pressure. Ethanol as an injection solvent resulted in peak broadening of the analogs within the entire pressure range studied. Solvents with an eluent strength of 3.4 or less were more suitable for use as injecting solvents.

Matched MeSH terms: Vitamin E/chemistry
Particle size analysis of nanocrystals: improved analysis method

Keck CM

Int J Pharm, 2010 May 5;390(1):3-12.
PMID: 19733647 DOI: 10.1016/j.ijpharm.2009.08.042

The influence of optical parameters, additional techniques (e.g. PIDS technology) and the importance of light microscopy were investigated by comparing laser diffraction data obtained via the conventional method and an optimized analysis method. Also the influence of a possible dissolution of nanocrystals during a measurement on the size result obtained was assessed in this study. The results reveal that dissolution occurs if unsaturated medium or microparticle saturated medium is used for the measurements. The dissolution is erratic and the results are not reproducible. Dissolution can be overcome by saturating the measuring medium prior to the measurement. If nanocrystals are analysed the dispersion medium should be saturated with the nanocrystals, because the solubility is higher than for coarse micro-sized drug material. The importance of using the optimized analysis method was proven by analysing 40 different nanosuspensions via the conventional versus the optimized sizing method. There was no large difference in the results obtained for the 40 nanosuspensions using the conventional method. This would have led to the conclusion, that all the 40 formulations investigated are physically stable. However, the analysis via the optimized method revealed that from 40 formulations investigated only four were physically stable. In conclusion an optimized analysis saves time and money and avoids misleading developments, because discrimination between "stable" and "unstable" can be done reliably at a very early stage of the development.

Matched MeSH terms: Vitamin E/chemistry
RGD-TPGS decorated theranostic liposomes for brain targeted delivery

Sonali, Singh RP, Sharma G, Kumari L, Koch B, Singh S, et al.

Colloids Surf B Biointerfaces, 2016 Nov 01;147:129-141.
PMID: 27497076 DOI: 10.1016/j.colsurfb.2016.07.058

The aim of this work was to formulate RGD-TPGS decorated theranostic liposomes, which contain both docetaxel (DTX) and quantum dots (QDs) for brain cancer imaging and therapy. RGD conjugated TPGS (RGD-TPGS) was synthesized and conjugation was confirmed by Fourier transform infrared (FTIR) spectroscopy and electrospray ionisation (ESI) mass spectroscopy (ESI-MS). The theranostic liposomes were prepared by the solvent injection method and characterized for their particle size, polydispersity, zeta-potential, surface morphology, drug encapsulation efficiency, and in-vitro release study. Biocompatibility and safety of theranostic liposomes were studied by reactive oxygen species (ROS) generation study and histopathology of brain. In-vivo study was performed for determination of brain theranostic effects in comparison with marketed formulation (Docel™) and free QDs. The particle sizes of the non-targeted and targeted theranostic liposomes were found in between 100 and 200nm. About 70% of drug encapsulation efficiency was achieved with liposomes. The drug release from RGD-TPGS decorated liposomes was sustained for more than 72h with 80% of drug release. The in-vivo results demonstrated that RGD-TPGS decorated theranostic liposomes were 6.47- and 6.98-fold more effective than Docel™ after 2h and 4h treatments, respectively. Further, RGD-TPGS decorated theranostic liposomes has reduced ROS generation effectively, and did not show any signs of brain damage or edema in brain histopathology. The results of this study have indicated that RGD-TPGS decorated theranostic liposomes are promising carrier for brain theranostics.

Matched MeSH terms: Vitamin E/chemistry*
Fulltext Tocotrienols promote apoptosis in human breast cancer cells by inducing poly(ADP-ribose) polymerase cleavage and inhibiting nuclear factor kappa-B activity

Loganathan R, Selvaduray KR, Nesaretnam K, Radhakrishnan AK

Cell Prolif, 2013 Apr;46(2):203-13.
PMID: 23510475 DOI: 10.1111/cpr.12014

OBJECTIVES: Tocotrienols and tocopherols are members of the vitamin E family, with similar structures; however, only tocotrienols have been reported to achieve potent anti-cancer effects. The study described here has evaluated anti-cancer activity of vitamin E to elucidate mechanisms of cell death, using human breast cancer cells.
MATERIALS AND METHODS: Anti-cancer activity of a tocotrienol-rich fraction (TRF) and a tocotrienol-enriched fraction (TEF) isolated from palm oil, as well as pure vitamin E analogues (α-tocopherol, α-, δ- and γ-tocotrienols) were studied using highly aggressive triple negative MDA-MB-231 cells and oestrogen-dependent MCF-7 cells, both of human breast cancer cell lines. Cell population growth was evaluated using a Coulter particle counter. Cell death mechanism, poly(ADP-ribose) polymerase cleavage and levels of NF-κB were determined using commercial ELISA kits.
RESULTS: Tocotrienols exerted potent anti-proliferative effects on both types of cell by inducing apoptosis, the underlying mechanism of cell death being ascertained using respective IC50 concentrations of all test compounds. There was marked induction of apoptosis in both cell lines by tocotrienols compared to treatment with Paclitaxel, which was used as positive control. This activity was found to be associated with cleavage of poly(ADP-ribose) polymerase (a DNA repair protein), demonstrating involvement of the apoptotic cell death signalling pathway. Tocotrienols also inhibited expression of nuclear factor kappa-B (NF-κB), which in turn can increase sensitivity of cancer cells to apoptosis.
CONCLUSION: Tocotrienols induced anti-proliferative and apoptotic effects in association with DNA fragmentation, poly(ADP-ribose) polymerase cleavage and NF-κB inhibition in the two human breast cancer cell lines.

Matched MeSH terms: Vitamin E/chemistry
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: Vitamin E/chemistry*

Filters

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

External Links