Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 24
Filtrar
Más filtros

Banco de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Br J Nutr ; 121(2): 155-163, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30392473

RESUMEN

Results of intervention studies on the effects of α-linolenic acid (ALA; C18 : 3n-3) on blood pressure (BP) are conflicting. Discrepancies between studies may be due to differences in study population, as subjects with increased baseline BP levels may be more responsive. Therefore, we examined specifically the effects of ALA on 24-h ambulatory blood pressure (ABP) in (pre-)hypertensive subjects. In a double-blind, randomised, placebo-controlled parallel study, fifty-nine overweight and obese adults (forty males and nineteen females) with (pre-)hypertension (mean age of 60 (sd 8) years) received daily 10 g refined cold-pressed flaxseed oil, providing 4·7 g (approximately 2 % of energy) ALA (n 29) or 10 g of high-oleic sunflower oil as control (n 30) for 12 weeks. Compliance was excellent as indicated by vial count and plasma phospholipid fatty-acid composition. Compared with control, the changes of -1·4 mmHg in mean arterial pressure (MAP; 24 h ABP) after flaxseed oil intake (95 % CI -4·8, 2·0 mmHg, P=0·40) of -1·5 mmHg in systolic BP (95 % CI -6·0, 3·0 mmHg, P=0·51) and of -1·4 mmHg in diastolic BP (95 % CI -4·2, 1·4 mmHg, P=0·31) were not statistically significant. Also, no effects were found for office BP and for MAP, systolic BP, and diastolic BP when daytime and night-time BP were analysed separately and for night-time dipping. In conclusion, high intake of ALA, about 3-5 times recommended daily intakes, for 12 weeks does not significantly affect BP in subjects with (pre-)hypertension.


Asunto(s)
Presión Sanguínea/efectos de los fármacos , Hipertensión/fisiopatología , Ácido alfa-Linolénico/administración & dosificación , Anciano , Monitoreo Ambulatorio de la Presión Arterial , Método Doble Ciego , Ácidos Grasos/sangre , Femenino , Humanos , Aceite de Linaza/administración & dosificación , Masculino , Persona de Mediana Edad , Obesidad/fisiopatología , Sobrepeso/fisiopatología , Fosfolípidos/sangre , Placebos , Ácido alfa-Linolénico/farmacología
2.
Cardiovasc Diabetol ; 16(1): 11, 2017 01 19.
Artículo en Inglés | MEDLINE | ID: mdl-28103890

RESUMEN

BACKGROUND/INTRODUCTION: Diabetes and cardiovascular disease develop in concert with metabolic abnormalities mirroring and causing changes in the vasculature, particularly the microcirculation. The microcirculation can be affected in different parts of the body of which the skin is the most easily accessible tissue. PURPOSE: The association between diabetes and dermal microvascular dysfunction has been investigated in observational studies. However, the strength of the association is unknown. Therefore we conducted a systematic review with meta-analysis on the association between diabetes and dermal microvascular dysfunction as assessed by laser Doppler/laser speckle contrast imaging with local thermal hyperaemia as non-invasive indicator of microvascular functionality. METHODS: PubMed and Ovid were  systematically searched for eligible studies through March 2015. During the first selection, studies were included if they were performed in humans and were related to diabetes or glucose metabolism disorders and to dermal microcirculation. During the second step we selected studies based on the measurement technique, measurement location (arm or leg) and the inclusion of a healthy control group. A random effects model was used with the standardised mean difference as outcome measure. Calculations and imputation of data were done according to the Cochrane Handbook. RESULTS: Of the 1445 studies found in the first search, thirteen cross-sectional studies were included in the meta-analysis, comprising a total of 857 subjects. Resting blood flow was similar between healthy control subjects and diabetes patients. In contrast, the microvascular response to local skin heating was reduced in diabetic patients compared to healthy control subjects [pooled effect of -0.78 standardised mean difference (95% CI -1.06, -0.51)]. This effect is considered large according to Cohen's effect size definition. The variability in effect size was high (heterogeneity 69%, p < 0.0001). However, subgroup analysis revealed no difference between the type and duration of diabetes and other health related factors, indicating that diabetes per se causes the microvascular dysfunction. CONCLUSION: Our meta-analysis shows that diabetes is associated with a large reduction of dermal microvascular function in diabetic patients. The local thermal hyperaemia methodology may become a valuable non-invasive tool for diagnosis and assessing progress of diabetes-related microvascular complications, but standardisation of the technique and quality of study conduct is urgently required.


Asunto(s)
Diabetes Mellitus/fisiopatología , Hiperemia/fisiopatología , Flujometría por Láser-Doppler/métodos , Microvasos/fisiopatología , Piel/irrigación sanguínea , Piel/fisiopatología , Complicaciones de la Diabetes/epidemiología , Complicaciones de la Diabetes/fisiopatología , Diabetes Mellitus/epidemiología , Calor , Humanos , Hiperemia/epidemiología , Microcirculación/fisiología , Estudios Observacionales como Asunto/métodos
3.
Clin Nutr ; 39(8): 2413-2419, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-31818531

RESUMEN

BACKGROUND: Only a limited number of studies have examined the vascular and postprandial effects of α-linolenic acid (ALA, C18:3n-3). Therefore, we performed a well-controlled trial focusing specifically on the effects of ALA on vascular function and metabolic risk markers during the fasting and postprandial phase in untreated (pre-)hypertensive individuals. METHODS: In a double-blind randomized, placebo-controlled parallel study, 59 overweight and obese adults (40 men and 19 women, aged 60 ± 8 years) with a high-normal blood pressure or mild (stage I) hypertension consumed daily either 10 g of refined cold-pressed flaxseed oil, providing 4.7 g ALA (n = 29), or 10 g of high-oleic sunflower (control) oil (n = 30) for 12 weeks. RESULTS: As compared with the high-oleic oil control, intake of flaxseed oil did not change brachial artery flow-mediated vasodilation, carotid-to-femoral pulse wave velocity, retinal microvascular calibers and plasma markers of microvascular endothelial function during the fasting and postprandial phase. Fasting plasma concentrations of free fatty acid (FFA) and TNF-α decreased by 58 µmol/L (P = 0.02) and 0.14 pg/mL (P = 0.03), respectively. No differences were found in other fasting markers of lipid and glucose metabolism, and low-grade systemic inflammation. In addition, dietary ALA did not affect postprandial changes in glucose, insulin, triacylglycerol, FFA and plasma inflammatory markers after meal intake. CONCLUSION: A high intake of ALA, about 3-5 times the recommended daily intake, for 12 weeks decreased fasting FFA and TNF-α plasma concentrations. No effects were found on other metabolic risk markers and vascular function during the fasting and postprandial phase in untreated high-normal and stage I hypertensive individuals.


Asunto(s)
Ayuno/fisiología , Hipertensión/terapia , Sobrepeso/complicaciones , Periodo Posprandial/efectos de los fármacos , Ácido alfa-Linolénico/administración & dosificación , Anciano , Presión Sanguínea , Arteria Braquial/fisiopatología , Factores de Riesgo Cardiometabólico , Método Doble Ciego , Endotelio Vascular/fisiopatología , Ácidos Grasos no Esterificados/sangre , Femenino , Humanos , Hipertensión/etiología , Hipertensión/fisiopatología , Aceite de Linaza/administración & dosificación , Masculino , Microvasos/fisiopatología , Persona de Mediana Edad , Sobrepeso/fisiopatología , Análisis de la Onda del Pulso , Aceite de Girasol/administración & dosificación , Factor de Necrosis Tumoral alfa/sangre , Vasodilatación/efectos de los fármacos
4.
Food Chem Toxicol ; 46(4): 1308-19, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17689850

RESUMEN

The Food and Drugs Administration has approved a health claim for soy based on clinical trials and epidemiological data indicating that high soy consumption is associated with a lower risk of coronary artery disease. Soy products contain a group of compounds called isoflavones, with genistein and daidzein being the most abundant. A number of cardioprotective benefits have been attributed to dietary isoflavones including a reduction in LDL cholesterol, an inhibition of pro-inflammatory cytokines, cell adhesion proteins and inducible nitric oxide production, potential reduction in the susceptibility of the LDL particle to oxidation, inhibition of platelet aggregation and an improvement in vascular reactivity. There is increasing interest in the use of nutrigenomic methods to understand the mechanisms by which isoflavones induce these changes, and in the use of nutrigenetics to understand why the effects vary between individuals. Nutrigenomics is a rapidly growing field making use of molecular biology methodologies, such as microarray technology and proteomics, to study how specific nutrients or diets affect gene expression and cellular protein levels. The analysis of differential gene expression and protein levels in endothelial cells, macrophages and smooth muscle cells is critical to elucidating the sequence of events leading to the formation of atherosclerotic lesions, and to understanding the potential anti-atherogenic properties of soy isoflavones. An increasing number of studies demonstrate a significant impact of genetic variation on changes in cardiovascular risk factors in response to dietary intervention. Nutrigenetic effects of this type have recently been reported for dietary isoflavones, and may help to explain some of the disparities in the current literature concerning isoflavones and cardiovascular health.


Asunto(s)
Enfermedades Cardiovasculares/metabolismo , Enfermedades Cardiovasculares/prevención & control , Dieta , Isoflavonas/farmacología , Animales , Enfermedades Cardiovasculares/genética , Genómica , Humanos , Metabolismo , Proteómica
5.
Biofactors ; 33(4): 281-91, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-19509463

RESUMEN

The oxidoreductase Macrophage Migration Inhibitory Factor (MIF) is discussed as a promising target for immunomodulatory therapy in patients with severe sepsis. Moreover, MIF expresses tautomerase as well as thiol-protein oxidoreductase activities and has a potential role in cellular redox homeostasis, apoptosis inhibition, endotoxin responsiveness as well as regulation of nuclear transcription factors. To further elucidate a potential role of intracellular MIF in severe sepsis, we assessed alterations of intracellular MIF content in peripheral blood leukocytes of patients with severe sepsis in comparison to healthy controls and non-septic patients after major surgery. Intracellular MIF was significantly elevated simultaneously in lymphocytes, B-cells, macrophages and granulocytes of patients with severe sepsis when compared to healthy control individuals (p < 0.05) and increased when compared to non-septic patients after major surgery. In parallel, plasma MIF levels were elevated in severe sepsis (p < 0.05). There was no difference of intracellular MIF in lymphocytes, B-cells, macrophages or granulocytes between surviving and non-surviving patients with severe sepsis (p > 0.05). However, in survivors LPS ex vivo stimulation increased MIF secretion but not in non-survivors of sepsis (p < 0.05). This finding underlines the role of intracellular MIF in inflammatory diseases. It suggests monitoring of intracellular MIF in further clinical and non-clinical research valuable.


Asunto(s)
Leucocitos/enzimología , Factores Inhibidores de la Migración de Macrófagos/sangre , Oxidorreductasas/sangre , Sepsis/sangre , Antígenos CD/sangre , Antígenos CD19/sangre , Complejo CD3/sangre , Antígenos CD4/sangre , Antígenos CD8/sangre , Moléculas de Adhesión Celular/sangre , Femenino , Proteínas Ligadas a GPI , Humanos , Receptores de Lipopolisacáridos/sangre , Subgrupos Linfocitarios/enzimología , Masculino , Sepsis/enzimología , Sepsis/mortalidad
6.
Am J Clin Nutr ; 86(5): 1369-75, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17991648

RESUMEN

BACKGROUND: The incidence of cardiovascular diseases increases after menopause, and soy consumption is suggested to inhibit disease development. OBJECTIVE: The objective was to identify biomarkers of response to a dietary supplementation with an isoflavone extract in postmenopausal women by proteome analysis of peripheral blood mononuclear cells. DESIGN: The study with healthy postmenopausal woman was performed in a placebo-controlled sequential design. Peripheral mononuclear blood cells were collected from 10 volunteers after 8 wk of receiving daily 2 placebo cereal bars and after a subsequent 8 wk of intervention with 2 cereal bars each providing 25 mg of isoflavones. The proteome of the cells was visualized after 2-dimensional gel electrophoresis, and peptide mass fingerprinting served to identify proteins that by the intervention displayed altered protein concentrations. RESULTS: Twenty-nine proteins were identified that showed significantly altered expression in the mononuclear blood cells under the soy-isoflavone intervention, including a variety of proteins involved in an antiinflammatory response. Heat shock protein 70 or a lymphocyte-specific protein phosphatase and proteins that promote increased fibrinolysis, such as alpha-enolase, were found at increased intensities, whereas those that mediate adhesion, migration, and proliferation of vascular smooth muscle cells, such as galectin-1, were found at reduced intensities after soy extract consumption. CONCLUSION: Proteome analysis identified in vivo markers that respond to a dietary intervention with isoflavone-enriched soy extract in postmenopausal women. The nature of the proteins identified suggests that soy isoflavones may increase the antiinflammatory response in blood mononuclear cells that might contribute to the atherosclerosis-preventive activities of a soy-rich diet.


Asunto(s)
Proteínas Sanguíneas/análisis , Glycine max , Isoflavonas/administración & dosificación , Leucocitos Mononucleares/química , Posmenopausia/sangre , Proteómica , Anciano , Biomarcadores , Femenino , Proteínas HSP70 de Choque Térmico/sangre , Humanos , Persona de Mediana Edad
7.
Mol Nutr Food Res ; 50(1): 58-69, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16502433

RESUMEN

Epidemiological studies suggest that soy consumption may provide a protection in the development and progression of atherosclerosis. It is under debate, however, whether the soy isoflavones or other compounds are the "active principle". As apoptosis is a driving force in the process of atherosclerosis, we tested whether a soy extract or a combination of the two predominant isoflavones genistein and daidzein, in concentrations as found in the extract, exert similar or different effects on apoptosis in EA.hy 926 endothelial cells after exposure to the endothelial stressor homocysteine. Plasma membrane disintegration and nuclear fragmentation served as relevant apoptosis markers. To assess whether the extract and the genistein/daidzein mixture differently affect cellular target proteins changed in amount by homocysteine treatment, proteome analysis was performed by two-dimensional gel-electrophoresis and peptide mass fingerprinting of regulated protein spots. Homocysteine induced apoptosis in the cells, and both extract and genistein/daidzein inhibited apoptosis to a comparable extent. Whereas the extract prevented for 10 proteins the changes in expression levels as caused by homocysteine, the genistein/daidzein mixture reversed the homocysteine effects on the proteome for 13 proteins. The cytoskeletal protein matrin 3 and a U5 snRNP-specific 40-kDa protein were the only protein entities where both extract and genistein/daidzein reversed the homocysteine-induced changes in a common way. In conclusion, our studies provide evidence that an isoflavone containing soy extract and isolated isoflavones, despite similar effects on inhibition of homocysteine-induced apoptosis in endothelial cells, affect a quite different spectrum of cellular target proteins.


Asunto(s)
Células Endoteliales/efectos de los fármacos , Glycine max/química , Homocisteína/farmacología , Isoflavonas/farmacología , Extractos Vegetales/farmacología , Proteoma/efectos de los fármacos , Apoptosis/efectos de los fármacos , Catepsina D/análisis , Línea Celular , Electroforesis en Gel Bidimensional , Expresión Génica/efectos de los fármacos , Genisteína/farmacología , Homocisteína/antagonistas & inhibidores , Isoflavonas/aislamiento & purificación , Lamina Tipo A/análisis , Proteínas Nucleares/análisis , ARN Mensajero/análisis , Proteínas de Unión al ARN , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Canal Aniónico 1 Dependiente del Voltaje/análisis
8.
Nutr Metab (Lond) ; 13: 34, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27182277

RESUMEN

BACKGROUND: Insulin-stimulated muscle blood flow facilitates plasma glucose disposal after a meal, a mechanism that is impaired in obese, insulin-resistant volunteers. Nitrate- or flavonoid-rich products, through their proposed effects on nitric oxide, may improve postprandial blood flow and, subsequently, glucose disposal. To investigate whether a single dose of nitrate-rich beetroot juice or flavonoid-rich black tea lowers postprandial muscle vascular resistance in obese volunteers and alters postprandial glucose or insulin concentrations. METHOD: In a randomised, controlled, cross-over study, 16 obese, insulin-resistant males consumed 75 g glucose, which was combined with 100 ml black tea, beetroot juice or control (water). Peripheral vascular resistance (VR), calculated as mean arterial pressure divided by blood flow, was assessed in the arm and leg conduit arteries, resistance arteries and muscle microcirculation across 3 h (every 30-min) after the oral glucose load. RESULTS: During control, we found no postprandial response in VR in conduit, resistance and microvessels (all P > 0.05). Black tea decreased VR compared to control in conduit, resistance and microvessels (all P < 0.05). Beetroot juice decreased postprandial VR in resistance vessels, but not in conduit artery and microvessels. Although postprandial glucose response was similar after all interventions, postprandial insulin response was attenuated by ~29 % after tea (P < 0.0005), but not beetroot juice. CONCLUSIONS: A single dose of black tea decreased peripheral VR across upper and lower limbs after a glucose load which was accompanied by a lower insulin response. Future studies in insulin-resistant subjects are warranted to confirm the observed effects and to explore whether long-term regular tea consumption affects glucose homeostasis. TRIAL REGISTRATION: The study was registered at clinicaltrials.gov on 30(th) November 2012 (NCT01746329).

9.
Free Radic Biol Med ; 38(9): 1170-9, 2005 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-15808414

RESUMEN

The oxidoreductase MIF is currently discussed as a new promising target of immunomodulatory therapy in patients with severe sepsis. An increasing body of evidence attributes an important role especially to intracellular MIF for regulation of endotoxin responsiveness as well as regulation of nuclear transcription factors. Up to now, measurement of MIF relied on ELISA techniques, lacking the ability to directly measure intracellular MIF and distinguish between different leukocyte subpopulations. Therefore, we developed a sensitive and robust flow cytometry-based method to reliably detect intracellular levels of MIF. This method can readily be applied in cultured cells as well as in subsets of human leukocytes in whole blood. Intracellular MIF content of whole-blood leukocyte subsets is detected simultaneously, and is individually determined for T-lymphocytes, B-lymphocytes, macrophages, and granulocytes, respectively. When tested in an ex vivo whole-blood stimulation system using PMA/Ionomycin the intracellular MIF content doubled in CD3+ T-lymphocytes and increased threefold in CD14+ macrophages. Baseline intracellular MIF levels of different leukocyte subpopulations were quantified in 22 healthy blood donors. Baseline intracellular MIF levels in T-lymphocytes are twice as high compared to those in B-lymphocytes and macrophages.


Asunto(s)
Leucocitos/metabolismo , Factores Inhibidores de la Migración de Macrófagos/sangre , Ensayo de Inmunoadsorción Enzimática , Citometría de Flujo , Humanos , Células Jurkat , Fenotipo , Reproducibilidad de los Resultados
10.
Am J Clin Nutr ; 101(4): 733-41, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25809853

RESUMEN

BACKGROUND: Plant sterols (PSs) lower LDL cholesterol, an established risk factor for coronary artery disease (CAD). No direct evidence is available supporting a reduced risk of CAD for foods with added PSs. Endothelial dysfunction is seen as an early indicator of atherosclerotic damage. OBJECTIVES: This study was primarily designed to investigate the effect of a low-fat spread with added PSs on brachial artery endothelial function as measured by flow-mediated dilation (FMD). Second, effects on arterial stiffness, blood pressure, serum lipids, and plasma PS concentrations were investigated. We hypothesized that PSs would not worsen FMD but would rather modestly improve FMD. DESIGN: This study had a double-blind, randomized, placebo-controlled, parallel design. After a 4-wk run-in period, 240 hypercholesterolemic but otherwise healthy men and women consumed 20 g/d of low-fat spread without (control) or with added PSs (3 g/d) during 12 wk. Pre- and postintervention, vascular function measurements and blood sampling were performed. RESULTS: In total, 232 participants completed the study period. For the primary endpoint FMD, 199 participants were included in the statistical analysis. PS intake did not affect FMD (+0.01 percentage points; 95% CI: -0.73, 0.75) compared with control. Measures of arterial stiffness (pulse wave velocity and augmentation index) and blood pressure were also not significantly changed compared with control. After PS intervention, LDL cholesterol significantly decreased on average by 0.26 mmol/L (95% CI: -0.40, -0.12) or 6.7% compared with control. Plasma sitosterol and campesterol concentrations significantly increased in the PS group up to on average 11.5 µmol/L and 13.9 µmol/L (expressed as geometric means), respectively. CONCLUSIONS: The intake of a low-fat spread with added PSs neither improved nor worsened FMD or other vascular function markers in hypercholesterolemic men and women. As expected, serum LDL cholesterol decreased, whereas plasma PSs increased after PS intake. This study was registered at clinicaltrials.gov as NCT01803178.


Asunto(s)
Biomarcadores/sangre , Arteria Braquial/efectos de los fármacos , Fitosteroles/sangre , Arteria Braquial/metabolismo , Colesterol/análogos & derivados , Colesterol/sangre , HDL-Colesterol/sangre , LDL-Colesterol/sangre , Carbohidratos de la Dieta/administración & dosificación , Grasas de la Dieta/administración & dosificación , Proteínas en la Dieta/administración & dosificación , Método Doble Ciego , Determinación de Punto Final , Ingestión de Energía , Femenino , Humanos , Hipercolesterolemia/sangre , Estilo de Vida , Masculino , Persona de Mediana Edad , Fitosteroles/administración & dosificación , Análisis de la Onda del Pulso , Sitoesteroles/sangre , Triglicéridos/sangre
11.
Nutrients ; 6(12): 5772-85, 2014 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-25514559

RESUMEN

Beneficial effects of flavonoid-rich black and green tea on macrocirculation have been well established. Theaflavins are unique to black tea as they are formed from catechins during the enzymatic oxidation of tea leaves. The study was performed to gain more insight into the effects of theaflavins on microcirculation and to compare effects with another important flavonoid class, the green tea derived catechins, which have been reported to improve vascular function. Twenty-four healthy subjects were included in a double-blind, placebo-controlled, randomised, cross-over study. On six different days, subjects received capsules with a single dose of catechins (500 mg), four varying doses of theaflavins (100 to 500 mg) or placebo. Microcirculation was assessed after each treatment by Pulse Amplitude Tonometry (EndoPAT) at baseline and 2, 4 and 6 h after test product intake. The EndoPAT reactive hyperemia response was improved by 500 mg catechins (reactive hyperemia index (RHI): 0.2; p = 0.04) and by 500 mg theaflavins (RHI: 0.19; p = 0.06) compared to placebo. Also, 300 mg theaflavins increased the RHI (0.28; p = 0.02), but no effects were observed at lower doses. The study suggests moderate effects of single doses of catechins and theaflavins on peripheral microcirculation.


Asunto(s)
Biflavonoides/farmacología , Sistema Cardiovascular/efectos de los fármacos , Catequina/farmacología , Té/química , Anciano , Biflavonoides/orina , Presión Sanguínea/efectos de los fármacos , Índice de Masa Corporal , Sistema Cardiovascular/metabolismo , Catequina/orina , Estudios Cruzados , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Femenino , Cromatografía de Gases y Espectrometría de Masas , Voluntarios Sanos , Humanos , Hiperemia/tratamiento farmacológico , Masculino , Persona de Mediana Edad , Análisis Multivariante , Resultado del Tratamiento
12.
Food Funct ; 5(7): 1613-20, 2014 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-24889137

RESUMEN

UNLABELLED: There is increasing evidence that tea and its non-caffeine components (primarily flavonoids) contribute to cardiovascular health. Randomized controlled trials have shown that tea can improve cardiovascular disease risk factors. We have previously reported a non-caffeine associated beneficial effect of regular black tea consumption on blood pressure and its variation. OBJECTIVE: To explore the non-caffeine associated effects of black tea on body weight and body fat distribution, and cardiovascular disease related metabolic outcomes. DESIGN: regular tea-drinking men and women (n = 111; BMI 20-35 kg m(-2)) were recruited to a randomized controlled double-blind 6 month parallel-designed trial. Participants consumed 3 cups per day of either powdered black tea solids (tea) or a flavonoid-free flavour- and caffeine-matched placebo (control). Body weight, waist- and hip-circumference, endothelial function and plasma biomarkers were assessed at baseline, 3 months and 6 months. RESULTS: Compared to control, regular ingestion of black tea over 3 months inhibited weight gain (-0.64 kg, p = 0.047) and reduced waist circumference (-1.88 cm, P = 0.035) and waist-to-hip ratio (-0.03, P = 0.005). These effects were no longer significant at 6 months. There were no significant effects observed on fasting glucose, insulin, plasma lipids or endothelial function. CONCLUSION: Our study suggests that short-term regular ingestion of black tea over 3 months can improve body weight and body fat distribution, compared to a caffeine-matched control beverage. However, there was no evidence that these effects were sustained beyond 3 months.


Asunto(s)
Composición Corporal/efectos de los fármacos , Camellia sinensis/química , Enfermedades Cardiovasculares/prevención & control , Té/química , Adulto , Anciano , Biomarcadores/sangre , Biomarcadores/orina , Glucemia/metabolismo , Presión Sanguínea/efectos de los fármacos , Peso Corporal/efectos de los fármacos , HDL-Colesterol/sangre , LDL-Colesterol/sangre , Método Doble Ciego , Endotelio/efectos de los fármacos , Endotelio/metabolismo , Femenino , Flavonoides/administración & dosificación , Humanos , Masculino , Persona de Mediana Edad , Extractos Vegetales/administración & dosificación , Triglicéridos/sangre , Circunferencia de la Cintura/efectos de los fármacos
13.
Food Funct ; 4(1): 111-5, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23038021

RESUMEN

There is increasing evidence that black tea polyphenols contribute to vascular health. We have recently shown that regular ingestion of polyphenol-rich black tea over 6 months results in lower systolic and diastolic blood pressure. However, the time course of these effects remains unclear. Therefore, our objective was to determine if short-term effects of tea on blood pressure could contribute to longer-term benefits of regular tea consumption on blood pressure. Men and women (n = 111) were recruited to a randomised placebo-controlled double-blind parallel designed trial. During a 4-week run-in, all participants consumed 3 cups per day of black tea. Participants then consumed 3 cups over 1 day of either powdered black tea solids containing 429 mg of polyphenols (tea), or a control product matched in flavour and caffeine content but containing no tea solids. The 24 h ambulatory blood pressure and heart rate was measured at the end of the 4-week run-in (baseline) and again during the 24 h intervention period. The 24 h day-time and night-time blood pressures were not significantly different between tea and control (P > 0.05). Baseline-adjusted net effects on mean 24 h ambulatory blood pressure for systolic and diastolic blood pressure were -0.2 mm Hg (95% CI, -1.5 to 1.0), P = 0.72, and 0.0 mm Hg (95% CI, -1.0 to 0.9), P = 0.95, respectively. Heart rate was significantly lower for tea compared to control during the night-time and early-morning periods (-2.0 (95% CI, -3.2, -0.8) bpm, and -1.9 (95% CI, -3.7, -0.2) bpm, respectively; P < 0.05 for both), but not during the day-time. These results suggest that the longer-term benefits of black tea on blood pressure are unlikely to be due to short-term changes.


Asunto(s)
Presión Sanguínea/efectos de los fármacos , Polifenoles/química , Polifenoles/farmacología , Té/química , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad
14.
Am J Clin Nutr ; 97(5): 943-50, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23553154

RESUMEN

BACKGROUND: Measures of blood pressure variation have been associated with cardiovascular disease and related outcomes. The regular consumption of black tea can lower blood pressure, but its effects on blood pressure variation have yet to be investigated. OBJECTIVE: We aimed to assess the effects of black tea consumption on the rate of ambulatory blood pressure variation. DESIGN: Men and women (n = 111) with systolic blood pressure between 115 and 150 mm Hg at screening were recruited in a randomized, controlled, double-blind, 6-mo parallel-designed trial designed primarily to assess effects on blood pressure. Participants consumed 3 cups/d of either powdered black tea solids (tea) or a flavonoid-free caffeine-matched beverage (control). The 24-h ambulatory blood pressure level and rate of measurement-to-measurement blood pressure variation were assessed at baseline, day 1, and 3 and 6 mo. RESULTS: Across the 3 time points, tea, compared with the control, resulted in lower rates of systolic (P = 0.0045) and diastolic (P = 0.016) blood pressure variation by ~10% during nighttime (2200-0600). These effects, which were immediate at day 1 and sustained over 6 mo, were independent of the level of blood pressure and heart rate. The rate of blood pressure variation was not significantly altered during daytime (0800-2000). CONCLUSIONS: These findings indicate that a component of black tea solids, other than caffeine, can influence the rate of blood pressure variation during nighttime. Thus, small dietary changes have the potential to significantly influence the rate of blood pressure variation. This trial was registered at the Australian New Zealand Clinical Trials Registry as ACTR12607000543482.


Asunto(s)
Presión Sanguínea/efectos de los fármacos , Extractos Vegetales/farmacología , Té/química , Adulto , Anciano , Australia , Monitoreo Ambulatorio de la Presión Arterial , Peso Corporal , Cafeína/administración & dosificación , Enfermedades Cardiovasculares/tratamiento farmacológico , Dieta , Método Doble Ciego , Femenino , Flavonoides/administración & dosificación , Frecuencia Cardíaca/efectos de los fármacos , Humanos , Estilo de Vida , Masculino , Persona de Mediana Edad
16.
Proteomics ; 7(18): 3278-88, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17708591

RESUMEN

Flaxseed is one of the richest sources of lignans that are converted to enterolactone by the intestinal microflora. Enterolactone has been suggested to be the prime active compound mediating atherosclerosis-protective effects that were shown for flaxseed. The effects of a 1-wk intervention with 0.4 g of flaxseed/kg body weight per day on enterolactone plasma levels in seven healthy men revealed that all participants (PAs) responded with enhanced enterolactone plasma levels. Proteome analysis of peripheral blood mononuclear cells (PBMC) from donors before, during, and after the intervention showed that flaxseed consumption affected significantly the steady-state levels of 16 proteins of which four were altered in a similar manner when blood mononuclear cells were exposed ex vivo to enterolactone. Enhanced levels of peroxiredoxin and reduced levels of the long-chain fatty acid beta-oxidation multienzyme complex may be taken as indicators of a reduced oxidative stress whereas reduced levels of glycoprotein IIIa/II could indicate improved protection from thrombotic and inflammatory processes. In conclusion, the blood mononuclear cell proteome responds to dietary flaxseed intake with changes in a number of atherosclerosis-relevant proteins that may be taken as biomarkers of exposure and some of these changes observed can be attributed to the action of the lignan metabolite enterolactone.


Asunto(s)
Aterosclerosis/prevención & control , Proteínas Sanguíneas/metabolismo , Dieta , Lino , Proteoma , 4-Butirolactona/análogos & derivados , 4-Butirolactona/sangre , Adulto , Electroforesis en Gel Bidimensional , Humanos , Lignanos/sangre , Masculino , Mapeo Peptídico , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción
17.
J Proteome Res ; 6(6): 2132-42, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17503794

RESUMEN

Apoptosis is a driving force in atherosclerosis development. A soy extract or a combination of the soy isoflavones genistein and daidzein inhibited apoptosis induced by oxidized LDL in endothelial cells. Proteome analysis revealed that the LDL-induced alterations of numerous proteins were reversed by the extract and the genistein/daidzein mixture but only three protein entities, all functionally linked to mitochondrial dysfunction, were regulated in common by both treatments.


Asunto(s)
Endotelio Vascular/efectos de los fármacos , Glycine max/química , Isoflavonas/farmacología , Lipoproteínas LDL/antagonistas & inhibidores , Mitocondrias/efectos de los fármacos , Proteoma/análisis , Apoptosis/efectos de los fármacos , Células Endoteliales/química , Células Endoteliales/efectos de los fármacos , Células Endoteliales/ultraestructura , Endotelio Vascular/química , Endotelio Vascular/ultraestructura , Genisteína/farmacología , Humanos , Lipoproteínas LDL/toxicidad , Mitocondrias/química , Mitocondrias/metabolismo , Oxidación-Reducción , Extractos Vegetales/farmacología , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción
19.
J Nutr ; 135(2): 199-205, 2005 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15671213

RESUMEN

For identification of the underlying molecular changes in hepatic lipid metabolism in zinc deficiency, rats were force-fed a zinc-deficient diet. Subsequently DNA-microarray and proteome profiling was performed in combination with hepatic lipid analysis. Of 6200 target sequences analyzed, 268 transcripts showed altered expression levels in livers of zinc-deficient rats, with 43 genes thereof related to hepatic lipid metabolism. Northern blot analysis and quantitative real-time RT-PCR were employed to confirm changes in mRNA levels. Proteins involved in lipid metabolism were identified by proteome analysis. Functional gene clusters with uniform changes in transcript levels suggested that the pathways required for lipolysis and mitochondrial as well as peroxisomal fatty acid degradation were downregulated, whereas those needed for de novo fatty acid synthesis and triglyceride assembly were increased. Subsequent enzymatic analysis of liver tissues confirmed an almost 40% greater triacylglycerol concentration in zinc-depleted rats, as well as an altered fatty acid composition of the lipid fraction as determined by gas chromatography. Liver lipids of zinc-deficient rats had significantly greater proportions of cis-9-oleic acid, cis-11-vaccenic acid, caprylic acid, myristic acid, alpha-linolenic acid, and eicosapentaenoic acid, and significantly less stearic and arachidonic acids. These alterations in hepatic metabolism are discussed in the context of changes in mRNA and protein levels of enzymes and transporters responsible for fatty acid metabolism, sequestration, and their transcriptional control.


Asunto(s)
Regulación de la Expresión Génica , Metabolismo de los Lípidos , Hígado/metabolismo , Proteoma , Transcripción Genética , Zinc/deficiencia , Animales , Masculino , Análisis de Secuencia por Matrices de Oligonucleótidos , ARN Mensajero/genética , Ratas , Valores de Referencia , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
20.
J Proteome Res ; 4(2): 369-76, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15822912

RESUMEN

Endothelial cells are primary targets for pro-atherosclerotic stressors such as oxidized LDL (ox-LDL). The isoflavone genistein, on the other hand, is suggested to prevent a variety of processes underlying atherosclerosis and cardiovascular diseases. By analyzing the proteome of EA.hy 926 endothelial cells, here we show, that genistein reverses the ox-LDL-induced changes of the steady-state levels of several proteins involved in atherosclerosis. These alterations caused by genistein are functionally linked to the inhibition of ox-LDL induced apoptosis.


Asunto(s)
Endotelio Vascular/efectos de los fármacos , Genisteína/farmacología , Lipoproteínas LDL/farmacología , Proteoma , Línea Celular , Electroforesis en Gel Bidimensional , Endotelio Vascular/citología , Endotelio Vascular/metabolismo , Humanos , Mapeo Peptídico , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Tripsina/química
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA