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1.
Nutr Metab Cardiovasc Dis ; 26(8): 743-51, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27105870

RESUMEN

BACKGROUND AND AIMS: Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) found in fish oil are postulated to have favourable effects on platelet, endothelial and vascular function. We investigated whether EPA has differential effects on in vivo platelet aggregation and other markers of cardiovascular risk compared to DHA. METHODS AND RESULTS: Following a 2 wk run-in taking encapsulated refined olive oil, 48 healthy young men were randomly allocated using a parallel design to receive EPA-rich (3.1 g EPA/d) or DHA-rich (2.9 g DHA/d) triglyceride concentrates or refined olive oil (placebo), for a total supplementary lipid intake of 5 g/d. The specified primary outcome was change in platelet monocyte aggregates (PMA); secondary outcomes were capillary density, augmentation index, digital pulse volume measurements, 24 h ambulatory BP, plasma 8-isoprostanes-F2α. Changes in the proportions of DHA and EPA in erythrocytes and non-esterified fatty acid composition indicated compliance to the intervention. There was no significant treatment effect on PMA (P = 0.382); mean changes (%) (95% CI) were placebo -0.5 (-2.0, 1.04), EPA 0.4 (-0.8, 1.6), DHA 0.3 (-1.5, 2.0). R-QUICKI, an index of insulin sensitivity, was greater following EPA compared to placebo (P < 0.05). No other significant differences were noted. CONCLUSION: Neither EPA- nor DHA-rich fish oil supplementation influence platelet-monocyte aggregation or several markers of vascular function after 6 wk in healthy young males. This trial was registered at clinicaltrials.gov as NCT01735357.


Asunto(s)
Plaquetas/efectos de los fármacos , Suplementos Dietéticos , Ácidos Docosahexaenoicos/administración & dosificación , Ácidos Eicosanoicos/administración & dosificación , Endotelio Vascular/efectos de los fármacos , Monocitos/efectos de los fármacos , Adhesividad Plaquetaria/efectos de los fármacos , Adolescente , Adulto , Biomarcadores/sangre , Plaquetas/metabolismo , Cápsulas , Endotelio Vascular/metabolismo , Voluntarios Sanos , Humanos , Resistencia a la Insulina , Londres , Masculino , Cumplimiento de la Medicación , Monocitos/metabolismo , Organización y Administración , Método Simple Ciego , Factores de Tiempo , Resultado del Tratamiento , Adulto Joven
2.
Diabet Med ; 31(11): 1310-5, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25047698

RESUMEN

AIMS: To investigate the relationship between adiposity and plasma free fatty acid levels and the influence of total plasma free fatty acid level on insulin sensitivity and ß-cell function. METHODS: An insulin sensitivity index, acute insulin response to glucose and a disposition index, derived from i.v. glucose tolerance minimal model analysis and total fasting plasma free fatty acid levels were available for 533 participants in the Reading, Imperial, Surrey, Cambridge, Kings study. Bivariate correlations were made between insulin sensitivity index, acute insulin response to glucose and disposition index and both adiposity measures (BMI, waist circumference and body fat mass) and total plasma free fatty acid levels. Multivariate linear regression analysis was performed, controlling for age, sex, ethnicity and adiposity. RESULTS: After adjustment, all adiposity measures were inversely associated with insulin sensitivity index (BMI: ß = -0.357; waist circumference: ß = -0.380; body fat mass: ß = -0.375) and disposition index (BMI: ß = -0.215; waist circumference: ß = -0.248; body fat mass: ß = -0.221) and positively associated with acute insulin response to glucose [BMI: ß = 0.200; waist circumference: ß = 0.195; body fat mass ß = 0.209 (P values <0.001)]. Adiposity explained 13, 4 and 5% of the variation in insulin sensitivity index, acute insulin response to glucose and disposition index, respectively. After adjustment, no adiposity measure was associated with free fatty acid level, but total plasma free fatty acid level was inversely associated with insulin sensitivity index (ß = -0.133), acute insulin response to glucose (ß = -0.148) and disposition index [ß = -0.218 (P values <0.01)]. Plasma free fatty acid concentration accounted for 1.5, 2 and 4% of the variation in insulin sensitivity index, acute insulin response to glucose and disposition index, respectively. CONCLUSIONS: Plasma free fatty acid levels have a modest negative association with insulin sensitivity, ß-cell secretion and disposition index but no association with adiposity measures. It is unlikely that plasma free fatty acids are the primary mediators of obesity-related insulin resistance or ß-cell dysfunction.


Asunto(s)
Adiposidad , Diabetes Mellitus Tipo 2/etiología , Ácidos Grasos no Esterificados/sangre , Resistencia a la Insulina , Células Secretoras de Insulina/metabolismo , Insulina/metabolismo , Obesidad/sangre , Adulto , Anciano , Índice de Masa Corporal , Estudios de Cohortes , Estudios Transversales , Diabetes Mellitus Tipo 2/epidemiología , Inglaterra/epidemiología , Femenino , Humanos , Secreción de Insulina , Modelos Lineales , Masculino , Persona de Mediana Edad , Obesidad/metabolismo , Obesidad/fisiopatología , Factores de Riesgo , Circunferencia de la Cintura
3.
J Hum Nutr Diet ; 26(4): 403-13, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23240718

RESUMEN

BACKGROUND: Effective nutrition health interventions are theory-based, as well as being drawn from practice and research, aiming to successfully accomplish dietary behavioural changes. However, the integration of theory, research and practice to develop community dietary educational programmes is a challenge that many interventionists feel ill equipped to achieve. METHODS: In the present study, a community-based education programme was designed for Bangladeshi patients with chronic kidney disease and hypertension. The goal of this programme was to reduce dietary salt intake in this population group, with a view to reducing their blood pressure and slowing kidney disease progression. RESULTS: The present study sets out the first four steps of a six-step model for creating a behaviour change programme. CONCLUSIONS: These four steps were concerned with the translation of theory and evidence into intervention objectives, and illustrate how a practical, community-based intervention was developed from behavioural theory, relevant research, knowledge of practice and the target patient group. Steps 5 and 6, which are concerned with implementation and evaluation, will be reported separately.


Asunto(s)
Presión Sanguínea , Dieta Hiposódica , Conductas Relacionadas con la Salud , Educación en Salud , Hipertensión/dietoterapia , Insuficiencia Renal Crónica/dietoterapia , Cloruro de Sodio Dietético/administración & dosificación , Bangladesh , Conducta Alimentaria , Humanos , Hipertensión/complicaciones , Ciencias de la Nutrición , Insuficiencia Renal Crónica/complicaciones , Investigación , Características de la Residencia , Investigación Biomédica Traslacional
4.
J Hum Nutr Diet ; 24(1): 86-95, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21114553

RESUMEN

BACKGROUND: People of Bangladeshi origin have the highest mortality ratio from coronary heart disease of any minority ethnic group in UK and their rate of kidney disease is three- to five-fold higher than that of the European UK population. However, there is little information regarding their dietary customs or knowledge, beliefs and attitudes towards health and nutrition. This multi-method qualitative study aimed to identify: (i) barriers and facilitators to dietary sodium restriction; (ii) traditional and current diet in the UK; and (iii) beliefs and attitudes towards development of hypertension, and the role of sodium. METHODS: Methods included focus group discussions, vignettes and food diaries. Twenty female chronic kidney disease patients attended four focus group discussions and maintained food diaries; ten responded to vignettes during telephone interviews. Triangulation of the results obtained from the three methods identified categories and themes from qualitative thematic analysis. RESULTS: Identified barriers to sodium restriction were deeply-rooted dietary beliefs, attitudes and a culturally-established taste for salt. Facilitators of change included acceptable strategies for cooking with less salt without affecting palatability. Dietary practices were culturally determined but modified by participants' prosperity in the UK relative to their previous impoverished agrarian lifestyles in Bangladesh. CONCLUSIONS: Cultural background and orientation were strong determinants of the group's dietary practices and influenced their reception and response to health communication messages. Efforts to understand their cultural mores, interpret and convey health-promotion messages in culturally-appropriate ways met with a positive response.


Asunto(s)
Dieta Hiposódica , Conducta Alimentaria/etnología , Conocimientos, Actitudes y Práctica en Salud , Fallo Renal Crónico/dietoterapia , Sodio en la Dieta/administración & dosificación , Aculturación , Actitud Frente a la Salud , Bangladesh/etnología , Dieta Hiposódica/etnología , Conducta Alimentaria/psicología , Femenino , Grupos Focales , Humanos , Fallo Renal Crónico/epidemiología , Masculino , Persona de Mediana Edad , Motivación , Reino Unido/epidemiología
5.
Science ; 291(5511): 2147-50, 2001 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-11251119

RESUMEN

Little is known about how patterns of cell types are organized to form brain structures of appropriate size and shape. To study this process, we employed in vivo electroporation during midbrain development to create ectopic sources of Sonic Hedgehog, a signaling molecule previously shown to specify different neuronal cell types in a concentration-dependent manner in vitro. We provide direct evidence that a Sonic Hedgehog source can control pattern at a distance in brain development and demonstrate that the size, shape, and orientation of the cell populations produced depend on the geometry of the morphogen source. Thus, a single regulatory molecule can coordinate tissue size and shape with cell-type identity in brain development.


Asunto(s)
Tipificación del Cuerpo , Mesencéfalo/embriología , Neuronas/citología , Proteínas/fisiología , Transactivadores , Animales , Animales Modificados Genéticamente , División Celular , Embrión de Pollo , Electroporación , Inducción Embrionaria , Expresión Génica , Proteínas Hedgehog , Hibridación in Situ , Mesencéfalo/citología , Morfogénesis , Proteínas/genética , Transducción de Señal
6.
Oncogene ; 34(13): 1718-28, 2015 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-24769897

RESUMEN

ORCTL3 is a member of a group of genes, the so-called anticancer genes, that cause tumour-specific cell death. We show that this activity is triggered in isogenic renal cells upon their transformation independently of the cells' proliferation status. For its cell death effect ORCTL3 targets the enzyme stearoyl-CoA desaturase-1 (SCD1) in fatty acid metabolism. This is caused by transmembrane domains 3 and 4, which are more efficacious in vitro than a low molecular weight drug against SCD1, and critically depend on their expression level. SCD1 is found upregulated upon renal cell transformation indicating that its activity, while not impacting proliferation, represents a critical bottleneck for tumourigenesis. An adenovirus expressing ORCTL3 leads to growth inhibition of renal tumours in vivo and to substantial destruction of patients' kidney tumour cells ex vivo. Our results indicate fatty acid metabolism as a target for tumour-specific apoptosis in renal tumours and suggest ORCTL3 as a means to accomplish this.


Asunto(s)
Apoptosis , Neoplasias Renales/terapia , Transportadores de Anión Orgánico/genética , Estearoil-CoA Desaturasa/fisiología , Adenoviridae/genética , Animales , Transformación Celular Neoplásica , Células Cultivadas , Estrés del Retículo Endoplásmico , Femenino , Humanos , Neoplasias Renales/patología , Ratones , Transportadores de Anión Orgánico/fisiología , Estructura Terciaria de Proteína
7.
FEBS Lett ; 486(1): 29-32, 2000 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-11108837

RESUMEN

Xenopus laevis are a rich resource for vertebrate embryology and cell biology. Transplantation and transgenesis have provided much information about the developmental mechanisms of embryogenesis and molecule function, however existing methods have faced limitations regarding either the precise localization of gene expression or flexibility in the timing of gene transfer. Here we have found that electroporation of tailbud (stage 29/30) embryos is a rapid and efficient method of combining cell-specific expression with variation in temporal delivery. At the low voltages required for electroporation, embryos resumed normal swimming behavior and development. We conclude that electroporation has wide experimental application to Xenopus developmental and cell biology.


Asunto(s)
Electroporación/métodos , Embrión no Mamífero/fisiología , Natación , Transfección/métodos , Xenopus laevis/embriología , Xenopus laevis/genética , Animales , Dependovirus/genética , Dependovirus/fisiología , Conductividad Eléctrica , Desarrollo Embrionario , Expresión Génica , Nervio Óptico/metabolismo , Especificidad de Órganos , Regiones Promotoras Genéticas/genética , Factores de Tiempo , Transducción Genética , Transgenes/genética , Xenopus laevis/fisiología , Xenopus laevis/virología
8.
Am J Clin Nutr ; 48(3 Suppl): 822-5, 1988 09.
Artículo en Inglés | MEDLINE | ID: mdl-3414589

RESUMEN

The growth and development of children born of vegan mothers and reared on a vegan diet has been studied longitudinally: All of the children were breast-fed for the first 6 mo of life and in most cases well into the second year of life. The majority of children grew and developed normally but they did tend to be smaller in stature and lighter in weight than standards for the general population. Energy, calcium, and vitamin D intakes were usually below the recommended amounts. Their diets, however, were generally adequate but a few children had low intakes of riboflavin and vitamin B-12. Most parents were aware of the need to supplement the diet with vitamin B-12. It is concluded that provided sufficient care is taken, a vegan diet can support normal growth and development.


Asunto(s)
Desarrollo Infantil , Dieta Vegetariana , Crecimiento , Peso Corporal , Niño , Fenómenos Fisiológicos Nutricionales Infantiles , Preescolar , Dieta Vegetariana/efectos adversos , Ingestión de Energía , Femenino , Humanos , Lactante , Masculino , Factores Sexuales , Reino Unido
9.
Am J Clin Nutr ; 71(1 Suppl): 176S-8S, 2000 01.
Artículo en Inglés | MEDLINE | ID: mdl-10617968

RESUMEN

Intakes of partially hydrogenated fish oil and animal fats have declined and those of palm, soybean, sunflower, and rapeseed oils have increased in northern Europe in the past 30 y. Soybean and rapeseed oils are currently the most plentiful liquid vegetable oils and both have desirable ratios of n-6 to n-3 fatty acids. However, soybean and rapeseed oils are commonly partially hydrogenated for use in commercial frying to decrease susceptibility to oxidative degradation. This process leads to selective losses of alpha-linolenic acid (18:3n-3). Intake of linoleic acid (18:2n-6) has risen in many northern European countries. In the United Kingdom, intakes have increased from approximately 10 g/d in the late 1970s to approximately 15 g/d in the 1990s. The intake of alpha-linolenic acid is estimated to be approximately 1-2 g/d but varies with the type of culinary oil used. There are few reliable estimates of the intake of long-chain n-3 fatty acids, but those are generally approximately 0.1-0.5 g/d. The increased use of intensive, cereal-based livestock production systems has resulted in a lower proportion of n-3 fatty acids in meat compared with traditional extensive production systems. Overall, there has been a shift in the balance between n-6 and n-3 fatty acids over the past 30 y. This shift is reflected in the declining concentrations of docosahexaenoic acid and rising concentrations of linoleic acid in breast milk.


Asunto(s)
Grasas Insaturadas en la Dieta/administración & dosificación , Ácidos Grasos Insaturados/administración & dosificación , Aceites de Pescado/administración & dosificación , Aceites de Plantas/administración & dosificación , Tejido Adiposo/química , Animales , Bovinos , Productos Lácteos , Encuestas sobre Dietas , Ingestión de Alimentos , Europa (Continente) , Ácidos Grasos Esenciales/administración & dosificación , Femenino , Humanos , Ácido Linoleico/administración & dosificación , Masculino , Carne , Ovinos , Ácido alfa-Linolénico/administración & dosificación
10.
Am J Clin Nutr ; 70(3 Suppl): 555S-559S, 1999 09.
Artículo en Inglés | MEDLINE | ID: mdl-10479231

RESUMEN

Long-chain polyunsaturated fatty acids (LCPUFAs) derived from linoleic (18:2n-6) and alpha-linolenic (18:3n-3) acids are required for the normal development of the retina and central nervous system, but the extent to which they can be synthesized from the parent fatty acids is debated. Consuming LCPUFAs markedly increases their proportions in tissue lipids compared with their parent fatty acids. Thus, it has been argued that LCPUFAs must be supplied in the diet. LCPUFAs are generally absent from plant foods, thus it is important find out how essential fatty acid requirements are met by vegetarians. A developing fetus obtains LCPUFAs via selective uptake from its mother's plasma and LCPUFAs are present in the breast milk of vegetarians. There is no evidence that the capacity to synthesize LCPUFAs is limited in vegetarians. However, there are greater proportions of n-6 LCPUFAs and lower proportions of n-3 LCPUFAs in vegetarians compared with omnivores. This difference is probably a consequence of the selection of foods by vegetarians with high amounts of linoleic acid. Although lower concentrations of docosahexaenoic acid (22:6n-3; DHA) have been observed in blood and artery phospholipids of infants of vegetarians, it is uncertain whether their brain lipids contain lower proportions of DHA than do those of infants of omnivores. On the basis of experiments in primates that showed altered visual function with a high ratio of linoleic acid to alpha-linolenic acid, it would be prudent to recommend diets with a ratio between 4:1 and 10:1 in vegetarians and that excessive intakes of linoleic acid be avoided.


Asunto(s)
Dieta Vegetariana , Ácidos Grasos Esenciales/administración & dosificación , Lactancia/metabolismo , Sistema Nervioso Central/crecimiento & desarrollo , Ácidos Grasos Esenciales/análisis , Ácidos Grasos Esenciales/metabolismo , Ácidos Grasos Omega-3/metabolismo , Ácidos Grasos Omega-6 , Ácidos Grasos Insaturados/metabolismo , Femenino , Humanos , Recién Nacido , Leche Humana/química , Necesidades Nutricionales , Embarazo/metabolismo , Retina/crecimiento & desarrollo
11.
Am J Clin Nutr ; 59(5 Suppl): 1176S-1181S, 1994 05.
Artículo en Inglés | MEDLINE | ID: mdl-8172120

RESUMEN

The diets and growth of children reared on vegetarian diets are reviewed. Excessive bulk combined with low energy density can be a problem for children aged < or = 5 y and can lead to imparied growth. Diets that have a high content of phytate and other modifiers of mineral absorption are associated with an increased prevalence of rickets and iron-deficiency anemia. Vitamin B-12 deficiency is a real hazard in unsupplemented or unfortified vegan and vegetarian diets. It is suggested that vegans and vegetarians should use oils with a low ratio of linoleic to linolenic acid in view of the recently recognized role of docosahexaenoic acid in visual functioning. If known pitfalls are avoided, the growth and development of children reared on both vegan and vegetarian diets appears normal.


Asunto(s)
Dieta Vegetariana/efectos adversos , Anemia Hipocrómica/epidemiología , Anemia Hipocrómica/etiología , Peso al Nacer , Niño , Dieta , Femenino , Crecimiento , Humanos , Recién Nacido , Embarazo , Raquitismo/epidemiología , Raquitismo/etiología , Deficiencia de Vitamina B 12/epidemiología , Deficiencia de Vitamina B 12/etiología
12.
Am J Clin Nutr ; 68(6): 1202-7, 1998 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9846847

RESUMEN

BACKGROUND: Factor VII coagulant activity (FVII:c) is associated with an increased risk of fatal ischemic heart disease, is correlated with plasma triacylglycerol concentration, and increases after a meal rich in long-chain fatty acids. OBJECTIVE: We planned to compare effects of meals rich in oleate and butter fat with those of a low-fat meal on FVII:c and fibrinolytic activity. DESIGN: A crossover design was used to compare the postprandial effects on coagulant and fibrinolytic activities in 12 men of 3 high-fat (95 g) meals--high oleate, butter, and oleate + medium-chain triacylglycerols (oleate+MCT)--with an isoenergetic low-fat meal (18 g MCT). The oleate+MCT blend was used to mimic the ratio of long-chain to shorter-chain fatty acids in butter. RESULTS: Neither the amount nor type of fat consumed influenced plasminogen activator inhibitor 1 or t-plasminogen activator activities or D-dimer concentration. FVII:c increased by 12.5% (95% CI: 4.6%, 20.5%) after the high-fat meals at 3 h and by 6.7% (95% CI: 1.6%, 11.7%) at 7 h and changed 7 h after the low-fat meal by -14.3% (95% CI: -3.3%, -25.4%). The responses to the high-fat meals did not differ. Measurements of activated FVII (FVIIa), FVII zymogen, and activated FXII (FXIIa) concentrations made after the low-fat and high-oleate meals showed a significant increase in FVIIa only after the high-oleate meal. CONCLUSIONS: The results of this study confirm that FVII:c falls after a low-fat meal and suggests that postprandial activation of FVII occurs rapidly after a fat-rich meal without involving an increase in FXIIa.


Asunto(s)
Mantequilla , Grasas Insaturadas en la Dieta/administración & dosificación , Grasas de la Dieta/administración & dosificación , Factor VII/metabolismo , Fibrinólisis , Ácido Oléico/administración & dosificación , Adolescente , Adulto , Estudios Cruzados , Dieta con Restricción de Grasas , Factor XIIa/metabolismo , Productos de Degradación de Fibrina-Fibrinógeno/metabolismo , Humanos , Masculino , Inhibidor 1 de Activador Plasminogénico/metabolismo , Activador de Tejido Plasminógeno/metabolismo , Triglicéridos/sangre
13.
Am J Clin Nutr ; 31(5): 805-13, 1978 May.
Artículo en Inglés | MEDLINE | ID: mdl-645628

RESUMEN

The fatty acid composition of erythrocytes, of plasma choline phosphoglycerides, and of adipose tissue, serum cholesterol, triglyceride and vitamin B12 concentrations, weights, heights and skinfold thickness were determined on 22 vegans and 22 age and sex matched omnivore controls. The fatty acid composition of breast milk from four vegan and four omnivore control mothers, and of erythrocytes from three infants breast fed by vegan mothers and six infants breast fed by omnivore control mothers was determined. The proportions of linoleic acid and its long-chain derivatives were higher, the proportion of the long-chain derivatives of alpha-linolenic acid was lower, and the ratio of 22:5omega3/22:6omega3 was greater in the tissues of the vegans and infants breast-fed by vegans than in controls; the most marked differences were in the proportions of linoleic (18:2omega6) and docosahexenoic (22:6omega3) acids. Weights, skinfold thickness, serum vitamin B12, cholesterol and triglyceride concentrations were less in vegans than in controls. The difference in serum cholesterol concentration was most marked. It is concluded that a vegan-type diet may be the one of choice in the treatment of ischemic heart disease, angina pectoris, and certain hyperlipidemias.


Asunto(s)
Tejido Adiposo/metabolismo , Enfermedad Coronaria/etiología , Dieta Vegetariana , Ácidos Grasos/metabolismo , Leche Humana/metabolismo , Fosfatidilcolinas/sangre , Adulto , Anciano , Lactancia Materna , Colesterol/sangre , Enfermedad Coronaria/dietoterapia , Grasas de la Dieta , Eritrocitos/metabolismo , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Embarazo , Triglicéridos/sangre
14.
Am J Clin Nutr ; 57(3): 428-33, 1993 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8438779

RESUMEN

A matched-control study of plasma retinol, alpha-tocopherol, carotenoid, and cholesterol concentrations and the polyunsaturated fatty acid content of plasma and erythrocyte phospholipids was undertaken in 65 elderly patients with age-related maculopathy and 65 control subjects matched for age and sex. Despite the high statistical power of the study and large variations between subjects in the variables under consideration, no significant differences were noted between patients and control subjects. However, several statistically significant differences were noted between male and female subjects independent of their classification with maculopathy or as controls and age: plasma cholesterol, total phospholipids, alpha-tocopherol, and beta-cryptoxanthin concentrations were higher in females than in males. The mean plasma cholesterol concentration for the upper tertile of the whole sample was 7.6 mmol/L. Plasma concentrations of total carotenoids, alpha-carotene, and beta-carotene, but not alpha-tocopherol, were significantly lower in smokers than in non-smokers. The results of this study do not provide any evidence in favor of changing the dietary intake of polyunsaturated fatty acids or fat-soluble vitamins to protect against age-related maculopathy.


Asunto(s)
Envejecimiento , Colesterol/sangre , Ácidos Grasos Esenciales/sangre , Mácula Lútea , Enfermedades de la Retina/sangre , Vitaminas/sangre , beta Caroteno/análogos & derivados , Anciano , Carotenoides/análogos & derivados , Carotenoides/sangre , Criptoxantinas , Femenino , Humanos , Masculino , Fosfolípidos/sangre , Caracteres Sexuales , Fumar/sangre , Solubilidad , Vitamina E/sangre , Xantófilas
15.
Am J Clin Nutr ; 69(2): 220-5, 1999 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9989683

RESUMEN

BACKGROUND: The R353Q genotype is a major determinant of factor VII coagulant (FVIIc) activity, which is associated with an increased risk of ischemic heart disease (IHD) and elevated plasma triacylglycerol concentrations. OBJECTIVE: The objectives were to 1) compare the effects of meals rich in palmitate or oleate with those of a meal low in fat on FVIIc in subjects with moderately elevated plasma nonfasting triacylglycerol concentrations and 2) determine whether the postprandial increase in FVIIc induced by dietary oleate differs in carriers of the Q allele. DESIGN: Fifty-two men aged >52 y with nonfasting plasma triacylglycerol concentrations between 2 and 5.5 mmol/L were randomly assigned to receive isoenergetic (5.1 MJ) meals providing 50 g high-oleate or high-palmitate oils or a low-fat meal providing 15 g high-oleate oil. In a second study, 17 men aged >52 y who were heterozygous for factor VII R353Q polymorphism were age-matched with subjects homozygous for the R allele and their responses to a 50-g, high-oleate meal were measured. RESULTS: FVIIc decreased by 11% after the low-fat meal. FVIIc increased by 9% and FVIIa (the activated form of FVII) increased by 55% after the high-oleate meal, whereas FVIIc did not change but FVIIa increased by 25% after the high-palmitate meal. Fasting FVIIc and FVIIa concentrations were 24% and 48% lower, respectively, in men with the RQ genotype than in men with the RR genotype but increased postprandially in both groups with no evidence of a genotype interaction. CONCLUSIONS: A high-fat meal rich in oleate increases FVIIa, whereas a low-fat meal does not, in men at high risk of IHD, independent of R353Q genotype.


Asunto(s)
Grasas de la Dieta/administración & dosificación , Factor VII/efectos de los fármacos , Factor VII/genética , Heterocigoto , Homocigoto , Ácidos Oléicos/administración & dosificación , Ácidos Palmíticos/administración & dosificación , Factor VIIa/metabolismo , Genotipo , Humanos , Hipertrigliceridemia/sangre , Masculino , Persona de Mediana Edad , Proyectos Piloto , Polimorfismo Genético , Periodo Posprandial , Triglicéridos/sangre
16.
Am J Clin Nutr ; 73(4): 715-21, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11273845

RESUMEN

BACKGROUND: An elevated postprandial lipid concentration is believed to be atherogenic and to increase the risk of thrombosis. OBJECTIVE: The objective was to test whether the consumption of a stearic acid-rich structured triacylglycerol has adverse effects on postprandial fibrinolytic activity and lipemia, factor VII coagulant (FVII:c) activity, and activated FVII (FVIIa) concentrations. DESIGN: A randomized crossover design was used to compare the effects on middle-aged healthy men (n = 17) and women (n = 18) of meals enriched with cocoa butter, high-oleate sunflower oil (oleate), or a structured triacylglycerol containing stearic acid. RESULTS: The mean increases from fasting in plasma triacylglycerol 3 h after the oleate, cocoa butter, and structured triacylglycerol meals were 1.36 (95% CI: 1.17, 1.56), 1.39 (1.17,1.63), and 0.65 (0.50, 0.82) mmol/L, respectively. Tissue plasminogen activator activity increased and plasminogen activator type 1 activity decreased after all 3 meals. Plasma FVII:c increased after the oleate and cocoa butter meals but not after the structured triacylglycerol meal. The values 6 h after the oleate and cocoa butter meals were 11.3% (7.0%, 15.6%) and 9.9% (4.7%, 15.2%), respectively, and were significantly different (P < 0.0001 and P = 0.001, respectively) from the value after the triacylglycerol meal [2.1% (-1.1%, 5.3%)]. Plasma FVIIa increased after all 3 meals, more so after the oleate and cocoa butter meals than after the structured triacylglycerol meal. CONCLUSION: The consumption of stearic acid in the form of a structured triacylglycerol leads to less of an increase in plasma triacylglycerol and in FVII:c than does a meal enriched in cocoa butter or oleate.


Asunto(s)
Factor VII/metabolismo , Fibrinólisis , Lípidos/sangre , Periodo Posprandial , Ácidos Esteáricos/administración & dosificación , Triglicéridos/administración & dosificación , Adulto , Estudios Cruzados , Grasas de la Dieta/administración & dosificación , Factor VIIa/metabolismo , Femenino , Fibrinógeno/metabolismo , Fibrinopéptido A/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Ácido Oléico/administración & dosificación , Factores de Riesgo , Trombosis/prevención & control , Factores de Tiempo , Activador de Tejido Plasminógeno/metabolismo , Triglicéridos/sangre , Triglicéridos/química
17.
Am J Clin Nutr ; 72(2): 395-400, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10919933

RESUMEN

BACKGROUND: Oxidative damage to lipids may be involved in the etiology of atherosclerosis, cardiovascular disease in general, and cancer. The soy isoflavone phytoestrogens, genistein and daidzein, and equol (a daidzein metabolite produced by intestinal microflora) are antioxidants in vitro; equol is a particularly good inhibitor of LDL oxidation and membrane lipid peroxidation. OBJECTIVE: We sought to investigate the effects of a diet enriched with soy containing isoflavones on in vivo biomarkers of lipid peroxidation and resistance of LDL to oxidation, compared with a diet enriched with soy from which the isoflavones had been extracted. DESIGN: : A randomized, crossover design was used to compare diets enriched with soy that was low or high in isoflavones in 24 subjects. Plasma concentrations of an F(2)-isoprostane, 8-epi-prostaglandin F(2)(alpha) (8-epi-PGF(2)(alpha)), a biomarker of in vivo lipid peroxidation, and resistance of LDL to copper-ion-induced oxidation were determined. RESULTS: Plasma concentrations of 8-epi-PGF(2)(alpha) were significantly lower after the high-isoflavone dietary treatment than after the low-isoflavone dietary treatment (326 +/- 32 and 405 +/- 50 ng/L, respectively; P = 0.028) and the lag time for copper-ion-induced LDL oxidation was longer (48 +/- 2.4 and 44 +/- 1.9 min, respectively; P = 0.017). Lag time for oxidation of unfractionated plasma and plasma concentrations of malondialdehyde, LDL alpha-tocopherol, polyunsaturated fatty acids, and isoflavonoids did not differ significantly between dietary treatments. CONCLUSIONS: Consumption of soy containing naturally occurring amounts of isoflavone phytoestrogens reduced lipid peroxidation in vivo and increased the resistance of LDL to oxidation. This antioxidant action may be significant with regard to risk of atherosclerosis, cardiovascular disease in general, and cancer.


Asunto(s)
Dinoprost/análogos & derivados , Estrógenos no Esteroides/administración & dosificación , Glycine max , Isoflavonas/administración & dosificación , Peroxidación de Lípido , Lipoproteínas LDL/química , Adulto , Enfermedades Cardiovasculares/prevención & control , Estudios Cruzados , Dieta , Dinoprost/sangre , F2-Isoprostanos , Femenino , Humanos , Lipoproteínas LDL/sangre , Masculino , Neoplasias/prevención & control , Fitoestrógenos , Preparaciones de Plantas
18.
Am J Clin Nutr ; 73(6): 1040-4, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11382657

RESUMEN

BACKGROUND: Oxidative damage to lipids in vivo may be involved in the development of atherosclerosis and cancer. Onions and black tea are foods rich in flavonoids, predominantly the flavonoid quercetin, which is a potent in vitro inhibitor of membrane lipid peroxidation and LDL oxidation. OBJECTIVE: Our objective was to investigate the effects of consuming a high-flavonoid (HF) diet enriched with onions and black tea on indexes of oxidative damage in vivo compared with a low-flavonoid (LF) diet. DESIGN: Thirty-two healthy humans were studied in a randomized crossover design. Indexes of oxidative damage used were plasma F2-isoprostanes (a biomarker of lipid peroxidation in vivo) and the titer of antibodies to malondialdehyde (MDA)-modified LDL. RESULTS: There were no significant differences in the intake of macronutrients or assessed micronutrients, plasma F2-isoprostane concentrations, and MDA-LDL autoantibody titer between the HF and LF dietary treatments. In the men, however, plasma concentrations of the F2-isoprostane 8-epi-prostaglandin F2alpha were slightly higher after the HF treatment phase than after the LF treatment [0.31 +/- 0.029 nmol/L (111 +/- 10.4 ng/L) compared with 0.26 +/- 0.022 nmol/L (92 +/- 7.8 ng/L); P = 0.041]. In all subjects, plasma quercetin concentrations were significantly higher after the HF treatment phase than after the LF treatment: 221.6 +/- 37.4 nmol/L compared with less than the limit of detection of 66.2 nmol/L. CONCLUSION: Flavonoid consumption in onions and tea had no significant effect on plasma F2-isoprostane concentrations and MDA-LDL autoantibody titer in this study and thus does not seem to inhibit lipid peroxidation in humans.


Asunto(s)
Dieta , Dinoprost/sangre , Cebollas , Quercetina/farmacología , , Adulto , Autoanticuerpos/sangre , Autoanticuerpos/efectos de los fármacos , Estudios Cruzados , Dinoprost/análogos & derivados , Dinoprost/inmunología , F2-Isoprostanos , Femenino , Humanos , Masculino , Malondialdehído/inmunología , Persona de Mediana Edad , Quercetina/administración & dosificación
19.
Atherosclerosis ; 95(2-3): 223-9, 1992 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-1418095

RESUMEN

Dietary intakes, anthropometric indices and plasma lipoprotein and alpha-tocopherol concentrations were measured in premenopausal vegetarian women of Indian descent (n = 22) and in white women of European descent consuming either mixed (n = 22) or vegetarian diets (n = 18). The Indian women were shorter in height than the white women and had a higher proportion of body fat. Energy intakes were lower in the Indian women, both in absolute terms and per kg body weight. The proportion of energy derived from saturated fatty acids was lower and that from polyunsaturated fatty acids was greater in both Indian and white vegetarians compared with the subjects on mixed diets. Intakes of dietary fibre and vitamins C and E were higher in the white vegetarians compared with the other groups. Plasma concentrations of total and LDL cholesterol and apolipoprotein B and the ratio of apolipoprotein B/apolipoprotein AI were lower and HDL and HDL2 cholesterol, alpha-tocopherol concentrations and the ratio of alpha-tocopherol/cholesterol were greater in the white vegetarian group than in the other groups. Total plasma cholesterol was associated with measures of truncal obesity, especially subscapular skinfold thickness and the percentage energy derived from saturated fatty acids. Plasma concentrations of apo(a) were higher and those of HDL and HDL2 cholesterol and sex hormone binding globulin (SHBG) were lower in the Indian vegetarian women compared with both groups of white women. No relationship could be found between apo(a), HDL and HDL2 cholesterol concentration and nutrient intake but HDL and HDL2 were negatively associated with the proportion of body fat and apo(a) weakly with subscapular skinfold thickness.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Dieta Vegetariana , Grasas de la Dieta/farmacología , Proteínas en la Dieta/farmacología , Lipoproteínas/sangre , Composición Corporal , Europa (Continente)/etnología , Femenino , Humanos , India/etnología , Lipoproteínas/administración & dosificación , Análisis de Regresión , Factores de Riesgo , Reino Unido , Población Blanca
20.
Atherosclerosis ; 61(2): 129-34, 1986 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-3753548

RESUMEN

Twenty-three hypertriglyceridaemic patients treated with 15 g/day of a fish oil concentrate (Maxepa) showed the expected reduction in serum triglyceride concentration but levels of LDL apoprotein B (apoB), measured by radial immunodiffusion, increased significantly. Increases in LDL apoB did not correlate with lipoprotein phenotype or changes in serum triglyceride. Studies in eight normal volunteers demonstrated that the effect of fish oil on LDL apoB was not restricted to hypertriglyceridaemic subjects. In view of the evidence that LDL apoB may be a risk factor for coronary heart disease these findings raise questions regarding the use of fish oil in the treatment of hypertriglyceridaemia.


Asunto(s)
Apolipoproteínas B/sangre , Ácidos Docosahexaenoicos , Ácido Eicosapentaenoico , Ácidos Grasos Insaturados/farmacología , Lipoproteínas LDL/sangre , Triglicéridos/sangre , Adulto , Colesterol/sangre , HDL-Colesterol/sangre , LDL-Colesterol/sangre , Combinación de Medicamentos , Ácidos Grasos Insaturados/administración & dosificación , Femenino , Humanos , Masculino , Persona de Mediana Edad
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