RESUMEN
Vitamin A deficiency (VAD) remains a major health issue in developing nations, contributing to preventable childhood blindness. However, there is lack of recent data on xerophthalmia, especially among school-aged children in Malaysia. We hypothesized that xerophthalmia persists among rural schoolchildren in Malaysia and potentially associated with socio-demographic status and malnutrition. We conducted a cross-sectional study on 596 schoolchildren (8-12 years) from ten rural primary schools located in five states across Malaysia. Children meeting the criteria for xerophthalmia assessment included those diagnosed with vitamin A deficiency (VAD) (plasma retinol < 0.70 µmol/L) and marginal VAD (plasma retinol 0.70 to < 1.05 µmol/L). The overall prevalence of xerophthalmia was 48.8%, with the most common ocular sign being conjunctival xerosis (38.9%). The occurrence of xerophthalmia was negatively associated with retinol-binding protein 4 (RPB4) (P=0.003), alpha-carotene (P=0.04), hemoglobin (P=0.004), weight (P=0.02), body mass index (BMI) (P=0.04) and WAZ (weight-for-age z-score) (P=0.04) status. Based on multivariate logistic regression analysis, a higher risk of xerophthalmia was observed in boys (Adjusted odd ratio [AOR]: 1.7, 95% confidence interval [CI]: 1.2-2.5) and Orang Asli (OA, indigenous) schoolchildren (AOR: 2.0, 95% CI: 1.3-3.0), while schoolchildren with overweight/obesity status (AOR: 0.5, 95% CI: 0.3-0.8) were associated with a reduced risk of xerophthalmia. The present study unveils a high prevalence of xerophthalmia among vitamin A-deficient primary schoolchildren in rural areas of Malaysia, especially among the indigenous community. The identified socio-demographic and nutritional factors associated to xerophthalmia would facilitate the implementation of more targeted interventions in addressing these issues.
RESUMEN
Background: Vitamin E from palm oil, known as the tocotrienol-rich fraction (TRF), has been shown to have immune-enhancing activity. To date, only one dose of TRF (400 mg daily) has been tested in a clinical trial. The proposed study will evaluate the immune-enhancing activity effects of lower doses (200, 100 and 50 mg) in a clinical trial using an influenza vaccine as the immunological challenge. Methods: A single-centre, randomised, parallel, double-blinded, placebo-controlled clinical trial with balance allocation involving five arms will be conducted. The healthy volunteers recruited will be randomly assigned to one of the arms, and they will be asked to take the respective supplements (400 mg, 200 mg, 100 mg, 50 mg of TRF or placebo) daily with their dinner. The volunteers will receive the influenza vaccine after four weeks. They will be asked to return to the study site four weeks later. A blood sample will be taken for the study at baseline, four and eight weeks. Primary outcome measures will be antibody levels to influenza, blood leucocyte profile and cytokine production. Secondary outcomes will be correlating plasma vitamin E levels with immune responses, plasma proteins and gene expression patterns. The findings from this study will be published in relevant peer-reviewed journals and presented at relevant national and international scientific meetings. Conclusions: The recent world events have created the awareness of having a healthy and functional immune system. Nutrition plays an important role in helping the immune system to function optimally. This study will show the effects of lower doses of TRF in boosting the immune response of healthy individuals and also elucidate the mechanisms through which TRF exerts its immune-enhancing effects. Clinical trial registration: Australian New Zealand Clinical Trials Registry (ANZCTR) [ ACTRN12622000844741] dated 15 June 2022. Protocol version: 2.
Asunto(s)
Suplementos Dietéticos , Voluntarios Sanos , Vacunas contra la Influenza , Aceite de Palma , Tocotrienoles , Humanos , Vacunas contra la Influenza/inmunología , Vacunas contra la Influenza/administración & dosificación , Tocotrienoles/administración & dosificación , Aceite de Palma/administración & dosificación , Gripe Humana/prevención & control , Gripe Humana/inmunología , Método Doble Ciego , Vacunación , Adulto , Masculino , Vitamina E , Femenino , Agentes Inmunomoduladores , Citocinas/sangreRESUMEN
PURPOSE: Vitamin A deficiency (VAD) remains a significant contributor to childhood morbidity and mortality in developing countries; therefore, the implementation of sustainable and cost-effective approaches to control VAD is of utmost pertinence. This study aims to investigate the efficacy of red palm olein (RPO)-enriched biscuit supplementation in improving vitamin A, haematological, iron, and inflammatory status among vitamin A-deficient schoolchildren. METHODS: We conducted a double-blinded, randomised controlled trial involving 651 rural primary schoolchildren (8-12 years) with VAD in Malaysia. The schoolchildren were randomised to receive either RPO-enriched biscuits (experimental group, n = 334) or palm olein-enriched biscuits (control group, n = 317) for 6-month duration. RESULTS: Significant improvements in retinol and retinol-binding protein 4 levels were observed in both groups after supplementation (P < 0.001). The improvement in retinol levels were similar across groups among subjects with confirmed VAD (P = 0.40). Among those with marginal VAD, greater improvement in retinol levels was recorded in the control group (P < 0.001) but lacked clinical significance. The levels of α- and ß-carotenes, haematological parameters (haemoglobin, packed cell volume, mean corpuscular volume and mean corpuscular haemoglobin) and iron enhanced more significantly in the experimental group (P < 0.05). The significant reduction in the prevalence of microcytic anaemia (- 21.8%) and high inflammation (- 8.1%) was only observed in the experimental group. CONCLUSION: The supplementation of RPO-enriched biscuits enhanced levels of provitamin A carotenes, iron, and erythropoiesis, and exhibited anti-inflammatory effects. Therefore, the incorporation of RPO into National Nutritional Intervention Programs may be a potential measure to improve the health status of vitamin A-deficient children, among various other interventions. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov (NCT03256123).
Asunto(s)
Deficiencia de Vitamina A , Vitamina A , Niño , Humanos , Carotenoides , Provitaminas , Hierro , Eritropoyesis , Deficiencia de Vitamina A/tratamiento farmacológico , Deficiencia de Vitamina A/epidemiología , Suplementos Dietéticos , Estado NutricionalRESUMEN
Notwithstanding the global efforts made to control intestinal parasitic infections, soil-transmitted helminth (STH) infections are still one of the most prevalent infections globally, especially in developing countries. A double-blinded, randomized controlled trial was conducted on 343 primary schoolchildren (8-12 years old) with vitamin A deficiency (VAD) in rural areas of Malaysia to investigate the effects of red palm olein (RPO)-enriched biscuits on STH reinfection rates and infection intensities. The effects of the RPO-enriched biscuits (experimental group, n = 153) and palm olein (PO)-enriched biscuits (control group, n = 190), were assessed at 3- and 6-month after the administration of complete triple-dose albendazole (one dose of 400 mg for three consecutive days). The overall STH infection rate at baseline was recorded at 65.6%. At 6-month, a significantly lower reinfection rate of A. lumbricoides was observed in the experimental group (35.3%) compared to the control group (60.0%) (P< 0.05), and a significant reduction in fecal egg count (epg) of A. lumbricoides was observed in the experimental group from baseline (P< 0.001), but no significant reduction was observed in the control group. No significant differences in the reduction of infection intensities of T. trichiura and hookworm were observed between experimental and control groups at 3- and 6-month (P>0.05). These findings suggest the potential beneficial effects of RPO-enriched biscuit supplementation on the reinfection of A. lumbricoides, which could be attributed to its high carotenoids content by enhancing host immune response and mucosal epithelium integrity. However, further studies are warranted to confirm whether RPO supplementation could result in similar parasite-specific beneficial effects in other community settings, as well as to explore the underlying mechanisms.
Asunto(s)
Antihelmínticos , Ascariasis , Helmintiasis , Infecciones por Uncinaria , Tricuriasis , Deficiencia de Vitamina A , Animales , Ascaris lumbricoides , Reinfección/tratamiento farmacológico , Deficiencia de Vitamina A/tratamiento farmacológico , Tricuriasis/tratamiento farmacológico , Antihelmínticos/uso terapéutico , Helmintiasis/tratamiento farmacológico , Suelo/parasitología , Heces/parasitología , Suplementos DietéticosRESUMEN
Childhood malnutrition is known as a public health concern globally. The present study aims to assess the anthropometry and blood biochemical status of rural primary schoolchildren in Malaysia. A total of 776 children (7-11 years old) from ten rural primary schools from five states were included in this study. Nutritional outcomes were assessed based on sex, age group and school categories among the children (median age: 9 years (P25:8, P75:10)). The overall prevalence of malnutrition was 53·4 %. Vitamin A deficiency (VAD) was recorded at 20·6 and 39·8 % based on retinol and retinol-binding protein (RBP) levels, respectively. Anaemia, iron deficiency (ID), iron-deficiency anaemia (IDA) and elevated inflammation were found at 14·9, 17·9, 9·1 and 11·5 %, respectively. Malnutrition, VAD, anaemia, ID, IDA and elevated inflammation were more prevalent among Orang Asli (OA) schoolchildren compared with Non-Orang Asli schoolchildren. Higher occurrences of VAD and anaemia were also found among children aged <10 years. Retinol, RBP, α-carotene, ferritin and haemoglobin levels were lower among undernourished children. Besides, overweight/obese children exhibited a higher level of high-sensitivity C-reactive protein. Multivariate analysis demonstrated that OA school children (adjusted OR (AOR): 6·1; 95 % CI 4·1, 9·0) and IDA (AOR: 3·6; 95 % CI 1·9, 6·6) were associated with stunting among this population. The present study revealed that malnutrition, micronutrient deficiencies and anaemia are prevalent among rural primary schoolchildren in Malaysia, especially those from OA schools and younger age children (<10 years). Hence, more appropriate and targeted measures are needed to improve the nutritional status of these children.
Asunto(s)
Anemia Ferropénica , Anemia , Deficiencias de Hierro , Desnutrición , Obesidad Infantil , Deficiencia de Vitamina A , Niño , Humanos , Deficiencia de Vitamina A/epidemiología , Vitamina A , Prevalencia , Malasia/epidemiología , Desnutrición/epidemiología , Anemia Ferropénica/epidemiología , Estado Nutricional , Anemia/epidemiología , Anemia/etiología , Inflamación , Instituciones AcadémicasRESUMEN
Tocotrienol-rich fraction (TRF), a palm oil-derived vitamin E fraction, is reported to possess potent neuroprotective effects. However, the modulation of proteomes in differentiated human neuroblastoma SH-SY5Y cells (diff-neural cells) by TRF has not yet been reported. This study aims to investigate the proteomic changes implicated by TRF in human neural cells using a label-free liquid-chromatography-double mass spectrometry (LC-MS/MS) approach. Levodopa, a drug used in the treatment of Parkinson's disease (PD), was used as a drug control. The human SH-SY5Y neuroblastoma cells were differentiated for six days and treated with TRF or levodopa for 24 h prior to quantitative proteomic analysis. A total of 81 and 57 proteins were differentially expressed in diff-neural cells following treatment with TRF or levodopa, respectively. Among these proteins, 32 similar proteins were detected in both TRF and levodopa-treated neural cells, with 30 of these proteins showing similar expression pattern. The pathway enrichment analysis revealed that most of the proteins regulated by TRF and levodopa are key players in the ubiquitin-proteasome, calcium signalling, protein processing in the endoplasmic reticulum, mitochondrial pathway and axonal transport system. In conclusion, TRF is an essential functional food that affects differential protein expression in human neuronal cells at the cellular and molecular levels.
Asunto(s)
Neuroblastoma , Enfermedad de Parkinson , Tocotrienoles , Humanos , Tocotrienoles/farmacología , Tocotrienoles/uso terapéutico , Levodopa/farmacología , Proteómica , Enfermedad de Parkinson/tratamiento farmacológico , Cromatografía Liquida , Neuroblastoma/tratamiento farmacológico , Espectrometría de Masas en Tándem , Vitamina ERESUMEN
Vegetable oils having unsaturated fatty acids in the sn-2 position of triglyceride (TG) backbone might not raise serum cholesterol levels. We investigated the chronic effects of diets enriched with palm olein (IV64) (PO), cocoa butter (CB), or extra virgin olive oil (EVOO) with oleic acid primarily at the sn-2 position (66%, 75%, 87% sn-2 oleic acid, respectively) of the TG molecule in 40 healthy volunteers participated in this randomized, controlled, single-blinded, crossover trial. Following a 2-week run-in period, the subjects were given standardization meals (breakfast, lunch, and dinner) cooked with palm olein (IV72). Subjects were randomized to 1 of the 3 intervention groups; receiving baked products (brownies for breakfast and cookies for teatime) prepared with respective test fats accompanied with standardized low-fat meals for breakfast, lunch, and dinner prepared with palm olein (IV72) for all groups for 4 weeks in a crossover manner with 2-week washout period (given standardization meals). Anthropometric measurements, blood samples, and dietary intakes were measured before run-in and pre- and post-intervention. No significant difference was observed on the primary outcome of the study total: high-density lipoprotein cholesterol. All 3 test fats were found to exhibit similar lipid responses (total cholesterol, TG, lipoprotein (a), apolipoprotein-A1, apolipoprotein-B/A-1). Statistical difference was found on low-density lipoprotein cholesterol (CB>EVOO by 0.3 mmol/L, P = .003), high-density lipoprotein cholesterol (PO>CB by 0.04 mmol/L, P = .02) and apolipoprotein-B (EVOOAsunto(s)
Dieta
, Grasas de la Dieta
, Adulto
, HDL-Colesterol
, LDL-Colesterol
, Grasas de la Dieta/farmacología
, Humanos
, Ácido Oléico
, Aceite de Oliva
, Aceite de Palma
, Aceites de Plantas/farmacología
, Triglicéridos
RESUMEN
Carotenoids, fat-soluble pigments found ubiquitously in plants and fruits, have been reported to exert significant neuroprotective effects against free radicals. However, the neuroprotective effects of total mixed carotenes complex (TMC) derived from virgin crude palm oil have not been studied extensively. Therefore, the present study was designed to establish the neuroprotective role of TMC on differentiated human neural cells against 6-hydroxydopamine (6-OHDA)-induced cytotoxicity. The human neural cells were differentiated using retinoic acid for six days. Then, the differentiated neural cells were pre-treated for 24 hr with TMC before exposure to 6-OHDA. TMC pre-treated neurons showed significant alleviation of 6-OHDA-induced cytotoxicity as evidenced by enhanced activity of the superoxide dismutase (SOD) and catalase (CAT) enzymes. Furthermore, TMC elevated the levels of intra-neuronal dopamine and tyrosine hydroxylase (TH) in differentiated neural cells. The 6-OHDA induced overexpression of α-synuclein was significantly hindered in neural cells pre-treated with TMC. In proteomic analysis, TMC altered the expression of ribosomal proteins, α/ß isotypes of tubulins, protein disulphide isomerases (PDI) and heat shock proteins (HSP) in differentiated human neural cells. The natural palm phytonutrient TMC is a potent antioxidant with significant neuroprotective effects against free radical-induced oxidative stress.
RESUMEN
Oxidative stress is a critical factor that triggers a "domino" cascade of events leading to the degeneration of dopaminergic neurons in Parkinson disease. Tocotrienols (T3) have antioxidant effects and can protect neuronal cells against oxidative damage. In the present study, we investigated the neuroprotective effects of different forms of T3 (alpha, delta, gamma) or tocotrienol-rich fraction (TRF) against 6-hydroxydopamine (6-OHDA)-induced oxidative damage in differentiated SH-SY5Y human neural cells. Differentiating the SH-SY5Y cells with retinoic acid and a low-serum culture medium for 6 days allowed development of human dopamine-like neural cells. Subsequently, the differentiated SH-SY5Y neural cells were pretreated with different forms of T3 for 24 hours before these cells were exposed to 6-OHDA. The T3 analogues and TRF displayed neuroprotective effects (P < .05) via restoration of cell viability and activation of antioxidant enzymes (e.g., superoxide dismutase, catalase). Notably, TRF was highly efficient in scavenging reactive oxygen species and upregulating dopamine and tyrosine hydroxylase levels in the differentiated SH-SY5Y cells. Gamma-T3 exhibited the most potent effects in attenuating apoptosis, whereas alpha-T3 was most effective in preventing 6-OHDA-induced leakage of α-Synuclein. Delta-T3 displayed a noticeable effect in upregulating the dopamine receptor D2 gene expression compared with controls. These findings suggest T3 isoforms and TRF demonstrate significant neuroprotective effects in protecting differentiated neural cells against 6-OHDA-mediated oxidative stress.
Asunto(s)
Neuroblastoma , Fármacos Neuroprotectores , Tocotrienoles , Línea Celular Tumoral , Dopamina/metabolismo , Expresión Génica , Humanos , Neuroblastoma/metabolismo , Fármacos Neuroprotectores/farmacología , Oxidopamina/toxicidad , Especies Reactivas de Oxígeno/metabolismo , Receptores Dopaminérgicos , Tocotrienoles/farmacologíaRESUMEN
Nutrition can modulate host immune responses as well as promote anticancer effects. In this study, two nutritional supplements, namely gamma-tocotrienol (γT3) and Spirulina, were evaluated for their immune-enhancing and anticancer effects in a syngeneic mouse model of breast cancer (BC). Five-week-old female BALB/c mice were fed Spirulina, γT3, or a combination of Spirulina and γT3 (Spirulina + γT3) for 56 days. The mice were inoculated with 4T1 cells into their mammary fat pad on day 28 to induce BC. The animals were culled on day 56 for various analyses. A significant reduction (p < 0.05) in tumor volume was only observed on day 37 and 49 in animals fed with the combination of γT3 + Spirulina. There was a marked increase (p < 0.05) of CD4/CD127+ T-cells and decrease (p < 0.05) of T-regulatory cells in peripheral blood from mice fed with either γT3 or Spirulina. The breast tissue of the combined group showed abundant areas of necrosis, but did not prevent metastasis to the liver. Although there was a significant increase (p < 0.05) of MIG-6 and Cadherin 13 expression in tumors from γT3-fed animals, there were no significant (p > 0.05) differences in the expression of MIG-6, Cadherin 13, BIRC5, and Serpine1 upon combined feeding. This showed that combined γT3 + Spirulina treatment did not show any synergistic anticancer effects in this study model.
Asunto(s)
Antineoplásicos/farmacología , Neoplasias de la Mama/terapia , Suplementos Dietéticos , Inmunomodulación/efectos de los fármacos , Spirulina , Animales , Cromanos , Modelos Animales de Enfermedad , Femenino , Ratones , Ratones Endogámicos BALB C , Vitamina E/análogos & derivadosRESUMEN
Gamma-tocotrienol (γT3) is an analogue of vitamin E with beneficial effects on the immune system, including immune-modulatory properties. This study reports the immune-modulatory effects of daily supplementation of γT3 on host T helper (Th) and T regulatory cell (Treg ) populations in a syngeneic mouse model of breast cancer. Female BALB/c mice were fed with either γT3 or vehicle (soy oil) for 2 weeks via oral gavage before they were inoculated with syngeneic 4T1 mouse mammary cancer cells (4T1 cells). Supplementation continued until the mice were euthanized. Mice (n = 6) were euthanized at specified time-points for various analysis (blood leucocyte, cytokine production and immunohistochemistry). Tumour volume was measured once every 7 days. Gene expression studies were carried out on tumour-specific T lymphocytes isolated from splenic cultures. Supplementation with γT3 increased CD4+ (p < 0.05), CD8+ (p < 0.05) T-cells and natural killer cells (p < 0.05) but suppressed Treg cells (p < 0.05) in peripheral blood when compared to animals fed with the vehicle. Higher interferon (IFN)-γ and lower transforming growth factor (TGF)-êµ levels were noted in the γT3 fed mice. Immunohistochemistry findings revealed higher infiltration of CD4+ cells, increased expression of interleukin-12 receptor-beta-2 (IL-12êµ2R), interleukin (IL)-24 and reduced expression of cells that express the forkhead box P3 (FoxP3) in tumours from the γT3-fed animals. Gene expression studies showed the down-regulation of seven prominent genes in splenic CD4+ T cells isolated from γT3-fed mice. Supplementation with γT3 from palm oil-induced T cell-dependent cell-mediated immune responses and suppressed T cells in the tumour microenvironment in a syngeneic mouse model of breast cancer.
Asunto(s)
Suplementos Dietéticos , Linfocitos Infiltrantes de Tumor/inmunología , Neoplasias Mamarias Animales/inmunología , Linfocitos T Reguladores/inmunología , Microambiente Tumoral/efectos de los fármacos , gamma-Tocoferol/farmacología , Animales , Línea Celular Tumoral , Citocinas/inmunología , Femenino , Células Asesinas Naturales/inmunología , Neoplasias Mamarias Animales/tratamiento farmacológico , Ratones , Ratones Endogámicos BALB C , Proteínas de Neoplasias/inmunologíaRESUMEN
Cancer is a devastating disease that has claimed many lives. Natural bioactive agents from plants are gaining wide attention for their anticancer activities. Several studies have found that natural plant-based bioactive compounds can enhance the efficacy of chemotherapy, and in some cases ameliorate some of the side-effects of drugs used as chemotherapeutic agents. In this paper, we have reviewed the literature on the anticancer effects of four plant-based bioactive compounds namely, curcumin, myricetin, geraniin and tocotrienols (T3) to provide an overview on some of the key findings that are related to this effect. The molecular mechanisms through which the active compounds may exert their anticancer properties in cell and animal-based studies also discussed.
Asunto(s)
Antineoplásicos/uso terapéutico , Neoplasias/tratamiento farmacológico , Animales , Productos Biológicos/química , Productos Biológicos/uso terapéutico , Humanos , Neoplasias/inmunología , Plantas/químicaRESUMEN
Tocotrienols, the unsaturated form of vitamin E, were reported to modulate platelet aggregation and thrombotic mechanisms in pre-clinical studies. Using a Food and Drug Administration (FDA)-approved cartridge-based measurement system, a randomised, double-blind, crossover and placebo-controlled trial involving 32 metabolic syndrome adults was conducted to investigate the effect of palm-based tocotrienols and tocopherol (PTT) mixture supplementation on platelet aggregation reactivity. The participants were supplemented with 200 mg (69% tocotrienols and 31% α-tocopherol) twice daily of PTT mixture or placebo capsules for 14 days in a random order. After 14 days, each intervention was accompanied by a postprandial study, in which participants consumed 200 mg PTT mixture or placebo capsule after a meal. Blood samples were collected on day 0, day 14 and during postprandial for the measurement of platelet aggregation reactivity. Subjects went through a 15-day washout period before commencement of subsequent intervention. Fasting platelet aggregation reactivity stimulated with adenosine diphosphate (ADP) did not show substantial changes after supplementation with PTT mixture compared to placebo (p = 0.393). Concomitantly, changes in postprandial platelet aggregation reactivity remained similar between PTT mixture and placebo interventions (p = 0.408). The results of this study highlight the lack of inhibitory effect on platelet aggregation after short-term supplementation of PTT mixture in participants with metabolic syndrome.
Asunto(s)
Suplementos Dietéticos , Síndrome Metabólico/patología , Síndrome Metabólico/terapia , Fitoquímicos/administración & dosificación , Agregación Plaquetaria/efectos de los fármacos , Tocoferoles/administración & dosificación , Tocotrienoles/administración & dosificación , Adulto , Método Doble Ciego , Femenino , Humanos , Malasia , Masculino , Persona de Mediana Edad , Placebos/administración & dosificación , Resultado del TratamientoRESUMEN
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.
Asunto(s)
Inmunidad Adaptativa , Anticuerpos Antibacterianos/inmunología , Toxoide Tetánico/administración & dosificación , Vitamina E/administración & dosificación , Animales , Anticuerpos Antibacterianos/biosíntesis , Suplementos Dietéticos , Interferón gamma/biosíntesis , Interferón gamma/inmunología , Interleucina-4/biosíntesis , Interleucina-4/inmunología , Ratones , Sensibilidad y Especificidad , Células TH1/efectos de los fármacos , Células TH1/inmunología , Vitamina E/químicaRESUMEN
Breast cancer is the second most frequent cancer affecting women worldwide after lung cancer. The toxicity factor associated with synthetic drugs has turned the attention toward natural compounds as the primary focus of interest as anticancer agents. Vitamin E derivatives consisting of the well-established tocopherols and their analogs namely tocotrienols have been extensively studied due to their remarkable biological properties. While tocopherols have failed to offer protection, tocotrienols, in particular, α-, δ-, and γ-tocotrienols alone and in combination have demonstrated anticancer properties. The discovery of the antiangiogenic, antiproliferative, and apoptotic effects of tocotrienols, as well as their role as an inducer of immunological functions, not only reveals a new horizon as a potent antitumor agent but also reinforces the notion that tocotrienols are indeed more than antioxidants. On the basis of a transcriptomic platform, we have recently demonstrated a novel mechanism for tocotrienol activity that involves estrogen receptor (ER) signaling. In silico simulations and in vitro binding analyses indicate a high affinity of specific forms of tocotrienols for ERß, but not for ERα. Moreover, we have demonstrated that specific tocotrienols increase ERß translocation into the nucleus which, in turn, activates the expression of estrogen-responsive genes (MIC-1, EGR-1 and Cathepsin D) in breast cancer cells only expressing ERß cells (MDA-MB-231) and in cells expressing both ER isoforms (MCF-7). The binding of specific tocotrienol forms to ERß is associated with the alteration of cell morphology, caspase-3 activation, DNA fragmentation, and apoptosis. Furthermore, a recently concluded clinical trial seems to suggest that tocotrienols in combination with tamoxifen may have the potential to extend breast cancer-specific survival.
RESUMEN
Anti-angiogenic therapy is widely being used to halt tumour angiogenesis. In this study, the anti-angiogenic activity of palm tocotrienol-rich fraction (TRF) and its individual components (γ- and δ-tocotrienol) were first investigated in vitro in human umbilical vein endothelial cells (HUVEC) and 4T1 mouse mammary cancer cells. Results showed reduced levels of Interkeukin (IL)-8 and IL-6, two pro-angiogenic cytokines in HUVEC treated with palm tocotrienols compared with α-tocopherol (α-T) and control cells (P < 0.05). The production of IL-8 and IL-6 was lowest in δ-tocotrienol (δ-T3)-treated cells followed by γ-tocotrienol (γ-T3) and TRF. There was significant (P < 0.05) reduction in IL-8 and vascular endothelial growth factor (VEGF) production in 4T1 cells treated with TRF or δ-T3. There was decreased expression of VEGF and its receptors; VEGF-R1 (fms-like tyrosine kinase, Flt-1) and VEGF-R2 (Kinase-insert-domain-containing receptor, KDR/Flk-2) in tumour tissues excised from mice supplemented with TRF were observed. There was also decreased expression of VEGF-R2 in lung tissues of mice supplemented with TRF. These observations correlate with the smaller tumour size recorded in the tocotrienol-treated mice. This study confirms previous observations that palm tocotrienols exhibit anti-angiogenic properties that may inhibit tumour progression.
RESUMEN
BACKGROUND: 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. MATERIALS AND METHODS: Gene expression profiling was performed with MCF-7 cells at inhibitory conditions of IC(50) using Illumina's Sentrix Array Human-6 BeadChips. The expression levels of selected differentially expressed genes were verified by quantitative real-time-PCR (qRT-PCR). RESULTS: The treatment with tocotrienol-rich palm oil fraction (TRF), α-tocopherol and isomers of tocotrienols (α, γ, and δ) altered the expression of several genes that code for proteins involved in the regulation of immune response, tumour growth and metastatic suppression, apoptotic signalling, transcription, protein biosynthesis regulation and many others. CONCLUSION: Treatment of human MCF-7 cells with tocotrienol isomers causes the down-regulation of the API5 gene and up-regulation of the MIG6 gene and the differential expression of other genes reported to play a key role in breast cancer biology.
Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/genética , Antineoplásicos/farmacología , Proteínas Reguladoras de la Apoptosis/genética , Neoplasias de la Mama/genética , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Proteínas Nucleares/genética , Tocotrienoles/farmacología , Proteínas Supresoras de Tumor/genética , Proteínas Reguladoras de la Apoptosis/antagonistas & inhibidores , Línea Celular Tumoral , Regulación hacia Abajo , Femenino , Humanos , Proteínas Nucleares/antagonistas & inhibidores , Regulación hacia Arriba , alfa-Tocoferol/farmacologíaRESUMEN
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 < 0.05), with IC50 values 8.99, 4.79, 3.73, and 8.63 µg/mL, respectively. Tumor incidence and tumor load in TRF-supplemented BALB/c mice was decreased by 57.1% and 93.6% (P < 0.05), respectively. The induction of the IL-24 mRNA in the 4T1 cells by vitamin E decreased in the following order: δ-T3 > 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.
Asunto(s)
Antineoplásicos/farmacología , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Interleucinas/genética , Neoplasias Mamarias Experimentales/tratamiento farmacológico , Aceites de Plantas/química , Tocotrienoles/farmacología , Animales , Antineoplásicos/química , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Ensayos de Selección de Medicamentos Antitumorales , Interleucinas/inmunología , Neoplasias Mamarias Experimentales/inmunología , Neoplasias Mamarias Experimentales/patología , Ratones , Ratones Endogámicos BALB C , Conformación Molecular , Aceites de Plantas/farmacología , ARN Mensajero/genética , ARN Mensajero/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Estereoisomerismo , Tocotrienoles/químicaRESUMEN
INTRODUCTION: Basic research has indicated that tocotrienols have potent antiproliferative and proapoptotic effects that would be expected to reduce the effect of breast cancer. METHODS: We conducted a double-blinded, placebo-controlled pilot trial to test the effectiveness of adjuvant tocotrienol therapy in combination with tamoxifen for five years in women with early breast cancer. Two-hundred-forty women, aged between 40-60 years, with either tumor node metastases (TNM) Stage I or II breast cancer and estrogen receptor (ER) positive tumors were non-randomly assigned to two groups. The intervention group received tocotrienol rich fraction (TRF) plus tamoxifen whilst the control group received placebo plus tamoxifen, for five years. RESULTS: During the five years of study, 8 patients died due to breast cancer while 36 patients developed local or systemic recurrence. Five-year breast cancer specific survival was 98.3% (95% confidence interval (CI): 95.9% to 100%) in the intervention group and 95%, (95% CI: 91.1% to 98.9%) in the control group, while 5-years disease free survival was 86.7% (95% CI: 80.6% to 92.8%) and 83.3% (95% CI: 76.6% to 90.0%), respectively. Risk of mortality due to breast cancer was 60% (HR: 0.40; 95% CI: 0.08 to 2.05) lower in the intervention group versus the controls following adjustment for age, ethnicity, stage and lymph node status but this was not statistically significant. Adjuvant TRF therapy was not associated with breast cancer recurrence (HR: 0.84; 95% CI: 0.43-1.65). CONCLUSIONS: From the current study, there seems to be no association between adjuvant tocotrienol therapy and breast cancer specific survival in women with early breast cancer. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT01157026.
Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Antioxidantes/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Tamoxifeno/administración & dosificación , Tocotrienoles/administración & dosificación , Adulto , Neoplasias de la Mama/mortalidad , Quimioterapia Adyuvante , Supervivencia sin Enfermedad , Método Doble Ciego , Femenino , Humanos , Persona de Mediana Edad , Metástasis de la Neoplasia , Receptores de Estrógenos/metabolismo , Resultado del TratamientoRESUMEN
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.