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1.
Sci Rep ; 11(1): 16429, 2021 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-34385499

RESUMO

Tocopherols, strong antioxidants, may be useful in preventing dementia, but the epidemiological evidence is insufficient. We performed a community-based follow-up study of Japanese, the Circulatory Risk in Community Study, involving 3739 people aged 40-64 years at baseline (1985-1999). Incident disabling dementia was followed up from 1999 through 2020. For subtype analysis, we classified disabling dementia into that with and that without a history of stroke. Dietary intake of tocopherols (total, α, ß, γ, and δ) were estimated using 24-h recall surveys. During a median follow-up of 19.7 years, 670 cases of disabling dementia developed. Total tocopherol intake was inversely associated with risk of disabling dementia with multivariable hazard ratios (95% confidence intervals) of 0.79 (0.63-1.00) for the highest versus lowest quartiles of total tocopherol intake (P for trend = 0.05). However, the association was strengthened when further adjusted for α-linolenic acid intake (Spearman correlation with total tocopherol intake = 0.93), with multivariable hazard ratios of 0.50 (0.34-0.74) (P for trend = 0.001) but was weakened and nonsignificant when further adjusted for linoleic acid intake (Spearman correlation with total tocopherol intake = 0.92), with multivariable hazard ratios of 0.69 (0.47-1.01) (P for trend = 0.05). Similar but nonsignificant inverse associations were observed for α-, γ-, and δ-tocopherols but not for ß-tocopherol. These results were similar regardless of the presence of a history of stroke. Dietary tocopherol intake was inversely associated with risk of disabling dementia, but its independent effect was uncertain owing to a high intercorrelation of α-linolenic linoleic acids with total tocopherol intake. Even with such confounding, a diet high in tocopherols may help prevent the onset of dementia.


Assuntos
Demência/epidemiologia , Suplementos Nutricionais , Tocoferóis/administração & dosagem , Adulto , Demência/prevenção & controle , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco
2.
PLoS One ; 16(2): e0225869, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33556062

RESUMO

Cancer cells develop tactics to circumvent the interventions by desensitizing themselves to interventions. Amongst many, the principle routes of desensitization include a) activation of survival pathways (e.g. NF-kB, PARP) and b) downregulation of cell death pathways (e.g. CD95/CD95L). As a result, it requires high therapeutic dose to achieve tumor regression which, in turn damages normal cells through the collateral effects. Methods are needed to sensitize the low and non-responsive resistant tumor cells including cancer stem cells (CSCs) in order to evoke a better response from the current treatments. Current treatments including chemotherapy can induce cell death only in bulk cancer cells sparing CSCs and cancer resistant cells (CRCs) which are shown to be responsible for high recurrence of disease and low patient survival. Here, we report several novel tumor targeted sensitizers derived from the natural Vitamin E analogue (AMP-001-003). The drug design is based on a novel concept "A priori activation of apoptosis pathways of tumor technology (AAAPT) which is designed to activate specific cell death pathways and inhibit survival pathways simultaneously and selectively in cancer cells sparing normal cells. Our results indicate that AMP-001-003 sensitize various types of cancer cells including MDA-MB-231 (triple negative breast cancer), PC3 (prostate cancer) and A543 (lung cancer) cells resulting in reducing the IC-50 of doxorubicin in vitro when used as a combination. At higher doses, AMP-001 acts as an anti-tumor agent on its own. The synergy between AMP-001 and doxorubicin could pave a new pathway to use AAAPT leading molecules as neoadjuvant to chemotherapy to achieve better efficacy and reduced off-target toxicity compared to the current treatments.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Neoplasias/tratamento farmacológico , Tocoferóis/farmacologia , Células A549 , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Doxorrubicina/administração & dosagem , Doxorrubicina/farmacologia , Resistencia a Medicamentos Antineoplásicos , Ensaios de Seleção de Medicamentos Antitumorais , Sinergismo Farmacológico , Humanos , Células MCF-7 , Camundongos , Camundongos Nus , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/patologia , Neoplasias/patologia , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/patologia , Células PC-3 , Paclitaxel/administração & dosagem , Paclitaxel/farmacologia , Tocoferóis/administração & dosagem , Ensaios Antitumorais Modelo de Xenoenxerto
3.
Eur J Pharm Biopharm ; 158: 410-416, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33271303

RESUMO

Lipid mesophases are lyotropic liquid crystalline systems which differ from liposomes and other globular aggregates in dilute regimes due to their inner ordering. It is known that natural lipids enable to obtain a rich variety of nanosystems and many of them have been proposed as delivery agents for bioactive compounds. Due to their packing parameters, several classes of lipids found in natural sources are able to self-assemble into nonlamellar structures. Among lipids occurring in plants and algae, triglycerides display this tendency. In the present study we examine new nanosystems built with lipids extracted from the marine microalga Nannochloropsis sp and their use as carriers for lipophilic antioxidants. The antioxidants studied, curcumin and tocopherol were encapsulated with high rate in the carriers. The physico-chemical characterization of plain and loaded vectors showed their structure and localization site, as well as the structure-functionality relationship related to potential drug delivery. The results show that the cargo molecules play an active role in driving the interactions which characterize the overall structure of the aggregates. The systems studied showed several coexisting mesophases, the most predominant structure being of cubic symmetry.


Assuntos
Antioxidantes/administração & dosagem , Portadores de Fármacos/química , Lipídeos/química , Cristais Líquidos/química , Microalgas/química , Antioxidantes/farmacocinética , Curcumina/administração & dosagem , Curcumina/farmacocinética , Portadores de Fármacos/isolamento & purificação , Composição de Medicamentos/métodos , Lipídeos/isolamento & purificação , Estrutura Molecular , Tocoferóis/administração & dosagem , Tocoferóis/farmacocinética
4.
Mol Pharm ; 17(11): 4334-4345, 2020 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-32975949

RESUMO

A carrier-based, immunogenic cell death (ICD)-eliciting platinum(IV) chemotherapeutic agent was synthesized via complexation between an axially derivatized Pt(IV)-tocopherol and hyaluronan (HA)-tocopherol nanocarrier. The resultant HA-Pt(IV) complex demonstrated antiproliferative activity and induced calreticulin translocation, an indicator of ICD, in murine and human head and neck cancer (HNC) cells. The intratumorally administered HA-Pt(IV) treatments were tolerable and efficacious in both immunocompetent and immunodeficient mice with HNC, partially because of the direct cytotoxicity. Superior efficacy and survival were observed in the immunocompetent group, suggesting a possible Pt(IV)-induced immunological response, which would only manifest in animals with an intact immune system. Subsequent imaging of tumor tissues demonstrated increased macrophage infiltration in the HA-Pt(IV)-treated tumors compared to the nontreated controls and the cisplatin-treated tumors, suggesting favorable inflammatory activation. RNA sequencing of HA-Pt(IV)-treated tumors indicated that carbohydrate and vitamin metabolisms were the most important Kyoto Encyclopedia of Genes and Genomes pathways, and molecular function, biological process, and cellular component were highly enriched gene ontology categories.


Assuntos
Antineoplásicos/administração & dosagem , Cisplatino/administração & dosagem , Portadores de Fármacos/química , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/metabolismo , Ácido Hialurônico/química , Morte Celular Imunogênica/efeitos dos fármacos , Compostos Organoplatínicos/administração & dosagem , Tocoferóis/administração & dosagem , Animais , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Modelos Animais de Doenças , Feminino , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Hospedeiro Imunocomprometido , Masculino , Camundongos , Camundongos Endogâmicos C3H , Camundongos Nus , Resultado do Tratamento
5.
Neuropharmacology ; 177: 108236, 2020 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-32712274

RESUMO

Certain ligands slowly bind to acetylcholinesterase. As a result, there is a slow establishment of enzyme-inhibitor equilibrium characterized by a slow onset of inhibition prior reaching steady state. Three mechanisms account for slow-binding inhibition: a) slow binding rate constant kon, b) slow ligand induced-fit following a fast binding step, c) slow conformational selection of an enzyme form. The slow equilibrium may be followed by a chemical step. This later that can be irreversible has been observed with certain alkylating agents and substrate transition state analogs. Slow-binding inhibitors present long residence times on target. This results in prolonged pharmacological or toxicological action. Through several well-known molecules (e.g. huperzine) and new examples (tocopherol, trifluoroacetophenone and a 6-methyluracil alkylammonium derivative), we show that slow-binding inhibitors of acetylcholinesterase are promising drugs for treatment of neurological diseases such as Alzheimer disease and myasthenia gravis. Moreover, they may be of interest for neuroprotection (prophylaxis) against organophosphorus poisoning. This article is part of the special issue entitled 'Acetylcholinesterase Inhibitors: From Bench to Bedside to Battlefield'.


Assuntos
Acetilcolinesterase/metabolismo , Inibidores da Colinesterase/administração & dosagem , Inibidores da Colinesterase/metabolismo , Doenças do Sistema Nervoso/tratamento farmacológico , Doenças do Sistema Nervoso/enzimologia , Alcaloides/administração & dosagem , Alcaloides/metabolismo , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/enzimologia , Animais , Humanos , Miastenia Gravis/tratamento farmacológico , Miastenia Gravis/enzimologia , Ligação Proteica , Sesquiterpenos/administração & dosagem , Sesquiterpenos/metabolismo , Tocoferóis/administração & dosagem , Tocoferóis/metabolismo
6.
Int J Pharm ; 586: 119542, 2020 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-32553494

RESUMO

Hyaluronic acid (HA), a common biopolymer found in the extracellular fluid, was grafted with ß-cyclodextrin (ß-CD) to form a composite polymer that could form inclusion complexes with tocopherol (VE), enhancing its water-solubility and serving as a model drug delivery system. Herein, different copolymers were prepared with varying HA:ß-CD ratios and characterized. VE loading capacity was directly correlated with increased ß-CD composition in the polymers and morphological changes were observed upon VE binding. The host materials and their VE inclusion complexes are not cytotoxic, and are thus useful for VE and drug delivery.


Assuntos
Sistemas de Liberação de Medicamentos , Ácido Hialurônico/química , Tocoferóis/administração & dosagem , beta-Ciclodextrinas/química , Antioxidantes/administração & dosagem , Antioxidantes/química , Células HeLa , Humanos , Polímeros/química , Solubilidade , Tocoferóis/química , Água/química
7.
Health Phys ; 119(1): 12-20, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32205715

RESUMO

The aim of this study was to analyze the changes in mouse jejunum protein expression in response to prophylactic administration of two promising tocols, γ-tocotrienol (GT3) and α-tocopherol succinate (TS), as radiation countermeasures before irradiation to elucidate the molecular mechanism(s) of their radioprotective efficacy. Mice were administered GT3 or TS (200 mg kg) subcutaneously 24 h prior to exposure to 11 Gy Co γ-radiation, a supralethal dose for mice. Jejunum was harvested 24 h post-irradiation. Results of the two-dimensional differential in-gel electrophoresis (2D-DIGE), coupled with mass spectrometry, and advanced bioinformatics tools suggest that the tocols have a corresponding impact on expression of 13 proteins as identified by mass spectrometry. Ingenuity Pathway Analysis (IPA) reveals a network of associated proteins involved in inflammatory response, organismal injury and abnormalities, and cellular development. Relevant signaling pathways including actin cytoskeleton signaling, RhoA signaling, and Rho family GTPase were identified. This study reveals the major proteins, pathways, and networks involved in preventing the radiation-induced injury in gut that may be contributing to enhanced survival.


Assuntos
Regulação da Expressão Gênica/efeitos da radiação , Proteômica/métodos , Lesões por Radiação/prevenção & controle , Protetores contra Radiação/administração & dosagem , Tocoferóis/administração & dosagem , Irradiação Corporal Total/métodos , Citoesqueleto de Actina/efeitos da radiação , Animais , Modelos Animais de Doenças , Raios gama/efeitos adversos , Jejuno/anatomia & histologia , Jejuno/efeitos da radiação , Masculino , Espectrometria de Massas , Camundongos , Proteção Radiológica , Protetores contra Radiação/efeitos da radiação , Tocoferóis/efeitos da radiação
8.
Mol Carcinog ; 59(4): 365-389, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32017273

RESUMO

α-Tocopherol (α-T) is the major form of vitamin E (VE) in animals and has the highest activity in carrying out the essential antioxidant functions of VE. Because of the involvement of oxidative stress in carcinogenesis, the cancer prevention activity of α-T has been studied extensively. Lower VE intake or nutritional status has been shown to be associated with increased cancer risk, and supplementation of α-T to populations with VE insufficiency has shown beneficial effects in lowering the cancer risk in some intervention studies. However, several large intervention studies with α-T conducted in North America have not demonstrated a cancer prevention effect. More recent studies have centered on the γ- and δ-forms of tocopherols and tocotrienols (T3). In comparison with α-T, these forms have much lower systemic bioavailability but have shown stronger cancer-preventive activities in many studies in animal models and cell lines. γ-T3 and δ-T3 generally have even higher activities than γ-T and δ-T. In this article, we review recent results from human and laboratory studies on the cancer-preventive activities of different forms of tocopherols and tocotrienols, at nutritional and pharmacological levels. We aim to elucidate the possible mechanisms of the preventive actions and discuss the possible application of the available information for human cancer prevention by different VE forms.


Assuntos
Antioxidantes/farmacologia , Suplementos Nutricionais , Neoplasias/prevenção & controle , Vitamina E/farmacologia , Animais , Antioxidantes/administração & dosagem , Carcinogênese/efeitos dos fármacos , Humanos , Neoplasias/metabolismo , Neoplasias/patologia , Oxirredução/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Tocoferóis/administração & dosagem , Tocoferóis/classificação , Tocoferóis/farmacologia , Vitamina E/administração & dosagem
9.
J Am Coll Nutr ; 39(3): 216-223, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31291155

RESUMO

Objective: To understand how diet quality affects chronic disease etiology, the associations of 4 a priori diet quality indices with blood levels of lipid-soluble micronutrients and biomarkers of inflammation, lipid, and glucose metabolism were examined in 5 ethnic groups.Methods: In a cross-sectional design, the Adiposity Phenotype Study, a subset of the Multiethnic Cohort in Hawaii and Los Angeles, recruited participants of white, African American, Native Hawaiian, Japanese American, and Latino ancestry. A total of 896 men and 910 women completed a validated quantitative food frequency questionnaire and anthropometric measurements and donated a fasting blood sample. Using general linear models, covariate-adjusted mean levels of lipid-soluble micronutrients (total carotenes, lycopene, total tocopherols, total lutein, cryptoxanthins), biomarkers of inflammation (C-reactive protein [CRP], tumor necrosis factor-[Formula: see text]), adipokines (adiponectin, leptin), lipids (total cholesterol, high-density lipoprotein cholesterol [HDL-C], triglycerides), and glucose metabolism (glucose, insulin, homeostatic model assessment of insulin resistance [HOMA-IR]) were computed across tertiles of 4 a priori dietary indices Healthy Eating Index (HEI)-2010, Alternative HEI (AHEI)-2010, alternate Mediterranean Diet (aMED), Dietary Approaches to Stop Hypertension (DASH); trends were evaluated in models with diet quality scores as continuous variables.Results: With better diet quality, levels of carotenes, lutein, cryptoxanthin, adiponectin, and HDL-C were significantly higher (ptrend < 0.01), whereas levels of CRP, leptin, total cholesterol, triglycerides, glucose, insulin, and HOMA-IR were inversely associated (ptrend < 0.05) with diet quality. With the exception of cryptoxanthins and triglycerides, the associations were consistent across ethnic groups.Conclusions: These findings confirm the association between diet quality and nutrition-related biomarkers and support the idea that a high-quality diet positively influences biologic pathways involved in chronic disease etiology across different ethnic groups.


Assuntos
Biomarcadores/sangue , Doença Crônica/prevenção & controle , Dieta Saudável , Etnicidade/estatística & dados numéricos , Negro ou Afro-Americano/estatística & dados numéricos , Idoso , Asiático/estatística & dados numéricos , Carotenoides/administração & dosagem , Estudos de Coortes , Estudos Transversais , Feminino , Havaí , Hispânico ou Latino/estatística & dados numéricos , Humanos , Los Angeles , Masculino , Micronutrientes/sangue , Havaiano Nativo ou Outro Ilhéu do Pacífico/estatística & dados numéricos , Tocoferóis/administração & dosagem , População Branca/estatística & dados numéricos
10.
J Integr Med ; 18(1): 68-79, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31812339

RESUMO

OBJECTIVE: Tocotrienols (T3s) have been hypothesized to have greater antioxidant capacity than tocopherols (Ts) due to differences in biokinetics that affect their absorption and function. The present trial compares the antioxidant effectiveness following postprandial challenge of two different doses of α-T or palm T3-rich fraction (TRF) treatments and evaluates their dose-response effects on antioxidant status. METHODS: Ten healthy volunteers were given four different doses of vitamin E formulations (268 mg α-T, 537 mg α-T, 263 mg TRF or 526 mg TRF) in a cross-over postprandial trial. Blood was sampled at 0, 2, 4, 5, 6 and 8 hours after meal consumption and plasma antioxidant status including total glutathione, superoxide dismutase, malondialdehyde (MDA), ferric reducing antioxidant potential and trolox-equivalent antioxidant capacity, was analyzed. RESULTS: Supplementation with the different doses of either α-T or TRF did not significantly improve overall antioxidant status. There was no significant difference in overall antioxidant status among treatments at the different doses compared. However, a significant dose-response effect was observed for plasma MDA throughout the 8-hour postprandial period. MDA was significantly lower after the 537 mg α-T treatment, compared to the 268 mg α-T treatment; it was also lower after the 526 mg TRF treatment compared to the 263 mg TRF treatment (P < 0.05). CONCLUSION: T3 and α-T demonstrated similar antioxidant capacity, despite markedly lower levels of T3 in blood and lipoproteins, compared to α-T.


Assuntos
Antioxidantes/metabolismo , Tocoferóis/administração & dosagem , Tocotrienóis/administração & dosagem , Adolescente , Adulto , Biomarcadores/sangue , Relação Dose-Resposta a Droga , Feminino , Humanos , Masculino , Período Pós-Prandial , Adulto Jovem
11.
Ter Arkh ; 91(2): 118-125, 2019 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-31094182

RESUMO

Aim - analysis of data on the role of vitamin and carotenoid deficiency in the development of metabolic syndrome (MS), the consumption of individual vitamins and vitamin supplements, as well as estimation of the effectiveness of the use of vitamins in patients with MS. A review of the existing literature has been carried out in the databases of RINC, CyberLeninka, Google Scholar, Pubmed. The lack of vitamins is a risk factor for MS and its components. The diet of people with MS is characterized by excessive caloric content and at the same time contains an inadequate amount of most vitamins. The most frequent in patients with MS is the deficiency (blood level) of vitamin D, E, B vitamins, carotenoids. Among patients with MS, individuals with a reduced concentration of vitamins in the blood plasma are often found. In turn, among those with a deficiency of vitamins, MS is more often found. Low concentrations of 25(OH)D in the serum are associated with an increased risk of MS. An inverse association between the concentration of the hormonal form of vitamin 1.25(OH)2D3 in the serum and the development of MC has been found. In patients with MS, the α-tocopherol concentration associated with lipids is lower than in healthy individuals, and γ-tocopherol, on the contrary, is higher. Taking high doses of one of the vitamin E homologues shifts the balance between tocopherols in the blood plasma. Sufficient supply of the body with all vitamins involved in the formation of metabolically active forms of vitamins (D, B6, PP) is a necessary condition for the exercise of these biological functions by these vitamins. The lack of vitamins is a risk factor for MS and its components. Enrichment of the diet of patients with MS should be considered as a necessary favorable background for its treatment. Since the body has functional connections between vitamins, it is advisable to use not individual vitamins, but their complexes.


Assuntos
Dieta , Síndrome Metabólica/sangue , Tocoferóis/administração & dosagem , Complexo Vitamínico B/administração & dosagem , Vitamina E/administração & dosagem , Carotenoides , Suplementos Nutricionais , Humanos , Síndrome Metabólica/complicações , Deficiência de Vitamina A/complicações , Vitamina E/sangue , Deficiência de Vitamina E/complicações
12.
Int J Pharm ; 554: 134-148, 2019 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-30389474

RESUMO

Tocopherol-based lipids are widely used for nucleic acid delivery. Using tocopherol molecules, we designed and synthesized 5-HT functionalized lipids by tethering 5-hydroxytryptamine (5-HT), a small molecule ligand as the head group to a natural amphiphilic molecule namely α-tocopherol (Vitamin E). This is with the aim of delivering nucleic acids specifically into cells expressing the serotonin receptors (5-hydroxytryptamine[5-HT]) which are abundant in the central nervous system. In order to achieve target recognition, we adopted an approach wherein two structurally different lipid molecules having serotonin as the head group was conjugated to tocopherol via different linkers thus generating lipids with either free -NH2 or -OH moiety. The corresponding lipids designated as Lipid A (Tocopheryl carbonate serotonin-NH2) and Lipid B (Tocopheryl 2-hydroxy propyl ammonium serotonin-OH), were formulated with co-lipids 1,2-dioleoyl-sn-glycero-3-phosphatidyl-ethanolamine (DOPE) and 1,2-dioleoyl-sn-glycero-sn-3-phosphatidylcholine (DOPC) and evaluated for their ability to deliver plasmid DNA through reporter gene expression assays in vitro. Furthermore, the physicochemical characteristics and cellular interactions of the formulations were examined using serotonin-receptor enriched cells in order to distinguish the structural and functional attributes of both lipids. Cell-based gene expression studies reveal that in comparison to Lipid A, a formulation of Lipid B prepared with DOPE as the co-lipid, contributes to efficient uptake leading to significant enhancement in transfection. Specific interactions explored by molecular docking studies suggests the role of the hydroxyl moiety and the enantiospecific significance of serotonin- conjugated tocopherol lipids in recognizing these receptors thus signifying a promising lipid-based approach to target the serotonin receptors in the central nervous system.


Assuntos
DNA/administração & dosagem , Lipídeos/química , Serotonina/administração & dosagem , Tocoferóis/administração & dosagem , Animais , Linhagem Celular , Regulação da Expressão Gênica , Técnicas de Transferência de Genes , Genes Reporter/genética , Humanos , Lipossomos , Simulação de Acoplamento Molecular , Fosfatidilcolinas/química , Fosfatidiletanolaminas/química , Plasmídeos/administração & dosagem , Receptores de Serotonina/metabolismo , Serotonina/química , Relação Estrutura-Atividade , Tocoferóis/química , Transfecção
13.
Int J Pharm ; 551(1-2): 34-41, 2018 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-30201294

RESUMO

Transfersomes were prepared by using different polysorbates (i.e., Tween 20, 40, 60 and 80) and loaded with tocopherol acetate, a naturally-occurring phenolic compound with antioxidant activity. The vesicles showed unilamellar morphology, small size (∼85 nm), low polydispersity index (≤0.27), and high entrapment efficiency, which increased as a function of the length of the Tween fatty acid chain (from 72% to 90%). The long-term stability of the formulations was evaluated by means of the Turbiscan™ technology, which indicated their good stability, irrespective of the Tween used. The vesicles efficiently delivered tocopherol to the skin, and showed biocompatibility in vitro in keratinocytes and fibroblasts. Regardless of the Tween used, the transfersomes were able to protect skin cells from the oxidative damage induced by hydrogen peroxide. Additionally, transfersomes promoted cell proliferation and migration, which resulted in an acceleration of skin wound closure. These results demonstrated that tocopherol-loaded transfersomes bear potential as topical delivery system with antioxidant activity and wound healing properties.


Assuntos
Antioxidantes/administração & dosagem , Regeneração/efeitos dos fármacos , Fenômenos Fisiológicos da Pele/efeitos dos fármacos , Pele/efeitos dos fármacos , Tocoferóis/administração & dosagem , Vitaminas/administração & dosagem , Animais , Linhagem Celular , Humanos , Peróxido de Hidrogênio/toxicidade , Lipossomos , Camundongos , Estresse Oxidativo/efeitos dos fármacos , Pele/lesões , Suínos
14.
J Physiol ; 596(20): 4879-4891, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29989171

RESUMO

KEY POINTS: In vitro evidence has identified that coagulation is activated by increased oxidative stress, though the link and underlying mechanism in humans have yet to be established. We conducted the first randomised controlled trial in healthy participants to examine if oral antioxidant prophylaxis alters the haemostatic responses to hypoxia and exercise given their synergistic capacity to promote free radical formation. Systemic free radical formation was shown to increase during hypoxia and was further compounded by exercise, responses that were attenuated by antioxidant prophylaxis. In contrast, antioxidant prophylaxis increased thrombin generation at rest in normoxia, and this was normalised only in the face of prevailing oxidation. Collectively, these findings suggest that human free radical formation is an adaptive phenomenon that serves to maintain vascular haemostasis. ABSTRACT: In vitro evidence suggests that blood coagulation is activated by increased oxidative stress although the link and underlying mechanism in humans have yet to be established. We conducted the first randomised controlled trial to examine if oral antioxidant prophylaxis alters the haemostatic responses to hypoxia and exercise. Healthy males were randomly assigned double-blind to either an antioxidant (n = 20) or placebo group (n = 16). The antioxidant group ingested two capsules/day that each contained 500 mg of l-ascorbic acid and 450 international units (IU) of dl-α-tocopherol acetate for 8 weeks. The placebo group ingested capsules of identical external appearance, taste and smell (cellulose). Both groups were subsequently exposed to acute hypoxia and maximal physical exercise with venous blood sampled pre-supplementation (normoxia), post-supplementation at rest (normoxia and hypoxia) and following maximal exercise (hypoxia). Systemic free radical formation (electron paramagnetic resonance spectroscopic detection of the ascorbate radical (A•- )) increased during hypoxia (15,152 ± 1193 AU vs. 14,076 ± 810 AU at rest, P < 0.05) and was further compounded by exercise (16,569 ± 1616 AU vs. rest, P < 0.05), responses that were attenuated by antioxidant prophylaxis. In contrast, antioxidant prophylaxis increased thrombin generation as measured by thrombin-antithrombin complex, at rest in normoxia (28.7 ± 6.4 vs. 4.3 ± 0.2 µg mL-1 pre-intervention, P < 0.05) and was restored but only in the face of prevailing oxidation. Collectively, these findings are the first to suggest that human free radical formation likely reflects an adaptive response that serves to maintain vascular haemostasis.


Assuntos
Doença da Altitude/prevenção & controle , Antioxidantes/uso terapêutico , Exercício Físico , Hemostasia , Adulto , Doença da Altitude/sangue , Doença da Altitude/tratamento farmacológico , Antioxidantes/administração & dosagem , Ácido Ascórbico/administração & dosagem , Ácido Ascórbico/uso terapêutico , Carotenoides/administração & dosagem , Carotenoides/uso terapêutico , Humanos , Masculino , Trombina/metabolismo , Tocoferóis/administração & dosagem , Tocoferóis/uso terapêutico , Zeaxantinas/administração & dosagem , Zeaxantinas/uso terapêutico
15.
Nutrients ; 10(7)2018 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-29933640

RESUMO

Epidemiological studies have provided ambiguous evidence on the association between vitamin E and esophageal cancer risk. To resolve this controversy, we performed this meta-analysis. The literature was searched by using Excerpta Medica Database (EMBASE), PubMed, the Web of Science, and the Cochrane Library from the inception to April 2018. A random effect model was utilized to calculate the odds ratio (OR) with the 95% confidence interval (95% CI). Twelve articles reporting 14 studies involving 3013 cases and 11,384 non-cases were included. By comparing the highest category with the lowest category of dietary vitamin E intake, we found that dietary vitamin E intake was inversely related to esophageal cancer risk (OR = 0.47, 95% CI: 0.36⁻0.60). Subgroup analysis revealed that dietary vitamin E intake had a significantly negative association with both the esophageal squamous cell carcinoma risk (OR = 0.29, 95% CI: 0.18⁻0.44) and the esophageal adenocarcinoma risk (OR = 0.66, 95% CI: 0.49⁻0.88). No study significantly affected the findings in the sensitivity analysis. Publication bias was discovered, however, the OR (95% CI) remained unchanged after the trim-and-fill analysis. This meta-analysis showed that the higher dietary vitamin E intake is associated with a lower esophageal cancer risk. However, the association still needs to be upheld by more large-scaled randomized controlled trials and prospective studies.


Assuntos
Neoplasias Esofágicas/epidemiologia , Vitamina E/administração & dosagem , Adenocarcinoma/epidemiologia , Carcinoma de Células Escamosas do Esôfago/epidemiologia , Humanos , Estado Nutricional , Fatores de Risco , Tocoferóis/administração & dosagem
16.
Clin Cancer Res ; 24(11): 2585-2593, 2018 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-29514842

RESUMO

Purpose: Currently, <50% of high-risk pediatric solid tumors like neuroblastoma can be cured, and many survivors experience serious or life-threatening toxicities, so more effective, less toxic therapy is needed. One approach is to target drugs to tumors using nanoparticles, which take advantage of the enhanced permeability of tumor vasculature.Experimental Design: SN38, the active metabolite of irinotecan (CPT-11), is a potent therapeutic agent that is readily encapsulated in polymeric nanoparticles. Tocopherol oxyacetate (TOA) is a hydrophobic mitocan that was linked to SN38 to significantly increase hydrophobicity and enhance nanoparticle retention. We treated neuroblastomas with SN38-TOA nanoparticles and compared the efficacy with the parent prodrug CPT-11 using a mouse xenograft model.Results: Nanoparticle treatment induced prolonged event-free survival (EFS) in most mice, compared with CPT-11. This was shown for both SH-SY5Y and IMR-32 neuroblastoma xenografts. Enhanced efficacy was likely due to increased and sustained drug levels of SN38 in the tumor compared with conventional CPT-11 delivery. Interestingly, when recurrent CPT-11-treated tumors were re-treated with SN38-TOA nanoparticles, the tumors transformed from undifferentiated neuroblastomas to maturing ganglioneuroblastomas. Furthermore, these tumors were infiltrated with Schwann cells of mouse origin, which may have contributed to the differentiated histology.Conclusions: Nanoparticle delivery of SN38-TOA produced increased drug delivery and prolonged EFS compared to conventional delivery of CPT-11. Also, lower total dose and drug entrapment in nanoparticles during circulation should decrease toxicity. We propose that nanoparticle-based delivery of a rationally designed prodrug is an attractive approach to enhance chemotherapeutic efficacy in pediatric and adult tumors. Clin Cancer Res; 24(11); 2585-93. ©2018 AACR.


Assuntos
Antineoplásicos/administração & dosagem , Sistemas de Liberação de Medicamentos , Irinotecano/administração & dosagem , Nanopartículas , Pró-Fármacos/administração & dosagem , Tocoferóis/administração & dosagem , Animais , Antineoplásicos/farmacocinética , Linhagem Celular Tumoral , Modelos Animais de Doenças , Humanos , Injeções Intralesionais , Irinotecano/farmacocinética , Camundongos , Nanopartículas/química , Neuroblastoma/tratamento farmacológico , Neuroblastoma/mortalidade , Neuroblastoma/patologia , Pró-Fármacos/farmacocinética , Recidiva , Retratamento , Taxa de Sobrevida , Distribuição Tecidual , Tocoferóis/farmacocinética , Resultado do Tratamento , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
17.
Adv Clin Exp Med ; 27(1): 5-14, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29521038

RESUMO

BACKGROUND: Dioxins contribute to neurological disorders in humans and animals, causing also neurological disorders in offspring during prenatal and postnatal periods. These compounds significantly affect the development of the central nervous system (CNS) structures, which results in behavioral changes. Tocopherol (TCP) and acetylsalicylic acid (ASA) may provide protective measures to reduce the inflammatory effects in the CNS associated with free radicals generated by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), thus contributing to the reduction of the negative effects of dioxin. OBJECTIVES: The main objective of this study was to determine the influence of dioxin on rats and their behavioral functions, and to ascertain whether a combined administration of TCP and ASA to rats treated with TCDD shows the possibility of potential protective effect on the functioning of the CNS. MATERIAL AND METHODS: Experiments were performed on 75 female and 12 male Buffalo strain rats, which are offspring of females from particular study groups. TCDD was used in the experiments, TCP and ASA were administered orally every day for 3 weeks. Animals were subjected to behavioral testing: the tail and swimming tests. RESULTS: During the observation of the offspring of both sexes born to females exposed to TCDD, males did not demonstrate any attempt to swim, whereas in females, the immobility time was significantly extended. Assessing the response times from the tail test in the animals treated with dioxins in relation to the control group, it was demonstrated that the response time was extended in the 3rd measurement in both females and males. CONCLUSIONS: Dioxin is characterized by neurotoxic effect causing behavioral disorders associated with prolonged response times. The use of TCP after the administration of dioxins causes a significant reduction and improvement of reflex response times. In contrast, ASA reduces the reflex response times also in the offspring of females exposed to TCDD and ASA.


Assuntos
Aspirina/farmacologia , Comportamento Animal/efeitos dos fármacos , Sistema Nervoso Central/efeitos dos fármacos , Dioxinas/efeitos adversos , Tocoferóis/farmacologia , Animais , Animais Recém-Nascidos/metabolismo , Aspirina/administração & dosagem , Encéfalo/efeitos dos fármacos , Dioxinas/uso terapêutico , Feminino , Masculino , Dibenzodioxinas Policloradas , Gravidez , Efeitos Tardios da Exposição Pré-Natal , Substâncias Protetoras/farmacologia , Ratos , Tocoferóis/administração & dosagem
18.
J Oleo Sci ; 67(3): 283-288, 2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29459506

RESUMO

In this study, we measured the quantity of marine-derived tocopherol (MDT), a monounsaturated vitamin E (VE), stored in the body tissue of mice fed with a diet containing a VE-rich fraction extracted from salmon roe. We first prepared the calibration curves for the MDT concentration using an HPLC-fluorescence system. Ranging from 0.016 to 50 µg/mL, the slope was expressed as first-order equations, with R2 values = 0.99. The mice were fed with an AIN-93 based diet containing MDT in doses of 21.4 mg/kg for 4 weeks, and the storage in the heart, lung, liver, stomach, small intestine, large intestine, kidney, pancreas, spleen, testis, skeletal muscle, visceral white adipose tissue (WAT), subcutaneous WAT and brain was quantified. MDT was widely distributed in tissues throughout the whole body, with higher accumulations observed in the adipose tissue, liver and kidney. These results demonstrate means to estimating the MDT concentration in natural products and in the bodies of animals and contribute to the understanding of the physiological functions of MDT in relation to human health.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Óleos de Peixe/administração & dosagem , Tocoferóis/administração & dosagem , Tocoferóis/metabolismo , Tecido Adiposo/metabolismo , Animais , Óleos de Peixe/química , Fluorescência , Rim/metabolismo , Fígado/metabolismo , Masculino , Camundongos Endogâmicos , Distribuição Tecidual , Tocoferóis/análise
19.
J Control Release ; 268: 400-406, 2017 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-29097302

RESUMO

Phosphorylated tocopherols are a new class of lipid excipients that have demonstrated potential in pharmaceutical applications. Their ability to solubilise poorly water soluble drugs indicates their potential utility in improving bioavailability of drugs where solubility limits their bioavailability. In this study a commercial mixture of phosphorylated tocopherols, TPM was combined with medium chain triglyceride (MCT) as a formulation for CoQ10, and in vitro and in vivo performance compared to the effect of addition of alternative tocopherol-based excipients. In in vitro digestion experiments, CoQ10 was poorly solubilised in the digesting MCT as anticipated. Addition of TPM facilitated the enhanced solubilisation of CoQ10 as did vitamin E TPGS (TPGS). Other tocopherol derivatives (tocopherol acetate, tocopherol) were less effective at solubilising the active during the digestion process. The trends in in vitro solubilisation were conserved in the in vivo bioavailability of CoQ10 after oral administration to rats, with TPM and TPGS formulations providing approximately double the exposure of MCT alone, while the addition of the other tocopherol derivatives reduced the overall exposure. Collectively, the results indicate potential of TPM as a new solubilising excipient for use in oral drug delivery for poorly water soluble drugs.


Assuntos
Excipientes/administração & dosagem , Tocoferóis/administração & dosagem , Triglicerídeos/administração & dosagem , Ubiquinona/análogos & derivados , Administração Oral , Animais , Disponibilidade Biológica , Excipientes/química , Masculino , Ratos Sprague-Dawley , Solubilidade , Tocoferóis/química , Triglicerídeos/química , Ubiquinona/administração & dosagem , Ubiquinona/química , Ubiquinona/farmacocinética
20.
Sci Rep ; 7(1): 11542, 2017 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-28912593

RESUMO

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.


Assuntos
Suplementos Nutricionais , Síndrome Metabólica/patologia , Síndrome Metabólica/terapia , Compostos Fitoquímicos/administração & dosagem , Agregação Plaquetária/efeitos dos fármacos , Tocoferóis/administração & dosagem , Tocotrienóis/administração & dosagem , Adulto , Método Duplo-Cego , Feminino , Humanos , Malásia , Masculino , Pessoa de Meia-Idade , Placebos/administração & dosagem , Resultado do Tratamento
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