RESUMO
The synthesis and applications of anisotropic nanostructures have attracted much attention in the last decade. The nanoflower-type structures are one of the nanomaterials with anisotropic structures most investigated because of owing to high densities of edges, corners, and stepped atoms present on their nano-petals. Here, silver nanoparticles obtained by a one-step green synthesis method using extract from Kalanchoe Daigremontiana´s leaves are reported. To identify the compounds responsible for reduction of silver ions, the functional groups present in plant extract were investigated by UV-vis and FTIR. Ag nanoparticles were characterized by UV-vis, XPS, ζ-potential, XRD, and SEM-EDS. Different solvents were used to eliminate agglomeration of the silver nanoparticles. These solvents produced nanoflower-like morphology with abundant nano-petals. This is the first report of the synthesis of Ag nanoflowers formed by green synthesis method using Kalanchoe Daigremontiana extract. The synthesized Ag nanoflowers are faced center cubic structure in nature with a petal thickness approximately of 25 nm. Photocatalytic activity of the different Ag nanostructures was evaluated through the degradation of methylene blue, where the degradation time as low as 1 min is reported. Furthermore these green synthesized Ag nanoflowers were found to show high antibacterial activity against Gram-negative bacteria Escherichia coli and Gram-positive Staphylococcus aureus.
Assuntos
Antibacterianos/química , Química Verde , Kalanchoe/química , Nanopartículas Metálicas/química , Nanoestruturas/química , Prata/química , Anisotropia , Antibacterianos/farmacologia , Catálise , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Nanopartículas Metálicas/ultraestrutura , Azul de Metileno/química , Nanoestruturas/ultraestrutura , Oxirredução , Tamanho da Partícula , Processos Fotoquímicos , Extratos Vegetais/química , Folhas de Planta/química , Prata/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimentoRESUMO
PURPOSE: Obesity increases the risk of cardiovascular disease, type 2 diabetes mellitus and cancer development. Autophagy and apoptosis are critical processes for development and homeostasis in multicellular organisms and have been linked to a variety of disorders. We aimed to investigate whether the quantity and quality of dietary fat can influence these processes in the adipose tissue of obese people. METHODS: A randomized, controlled trial within the LIPGENE study assigned 39 obese people with metabolic syndrome to 1 of 4 diets: (a) a high-saturated fatty acid diet, (b) a high-monounsaturated fatty acid (HMUFA) diet, and (c, d) two low-fat, high-complex carbohydrate diets supplemented with long-chain n-3 polyunsaturated fatty acids (LFHCC n-3) or placebo (LFHCC), for 12 weeks each. RESULTS: We found an increase in the expression of autophagy-related BECN1 and ATG7 genes after the long-term consumption of the HMUFA diet (p = 0.001 and p = 0.004, respectively) and an increase in the expression of the apoptosis-related CASP3 gene after the long-term consumption of the LFHCC and LFHCC n-3 diets (p = 0.001 and p = 0.029, respectively). CASP3 and CASP7 gene expression changes correlated with HOMA index. CONCLUSION: Our results suggest that the processes of autophagy and apoptosis in adipose tissue may be modified by diet and that the consumption of a diet rich in monounsaturated fat may contribute to adipose tissue homeostasis by increasing autophagy. They also reinforce the notion that apoptosis in adipose tissue is linked to insulin resistance. CLINICAL TRIAL REGISTRATION NUMBER: ClinicalTrials.gov NCT00429195.
Assuntos
Adipócitos/citologia , Tecido Adiposo/fisiopatologia , Apoptose , Autofagia , Gorduras na Dieta/administração & dosagem , Adulto , Idoso , Proteína 7 Relacionada à Autofagia/genética , Proteína 7 Relacionada à Autofagia/metabolismo , Proteína Beclina-1/genética , Proteína Beclina-1/metabolismo , Glicemia/metabolismo , Caspase 3/genética , Caspase 3/metabolismo , Caspase 7/genética , Caspase 7/metabolismo , Dieta com Restrição de Gorduras , Dieta Hiperlipídica , Ácidos Graxos/administração & dosagem , Ácidos Graxos Monoinsaturados/administração & dosagem , Ácidos Graxos Ômega-3/administração & dosagem , Feminino , Regulação da Expressão Gênica , Homeostase , Humanos , Resistência à Insulina , Masculino , Síndrome Metabólica/fisiopatologia , Pessoa de Meia-Idade , Obesidade/fisiopatologia , Método Simples-CegoRESUMO
BACKGROUND AND AIMS: CCAAT/enhancer-binding protein alpha (CEBPA) is a transcription factor involved in adipogenesis and energy homeostasis. Caloric restriction reduces CEBPA protein expression in patients with metabolic syndrome (MetS). A previous report linked rs12691 SNP in CEBPA to altered concentration of fasting triglycerides. Our objective was to assess the effects of rs12691 in glucose metabolism in Metabolic Syndrome (MetS) patients. METHODS AND RESULTS: Glucose metabolism was assessed by static (glucose, insulin, adiponectin, leptin and resistin plasma concentrations) and dynamic (disposition index, insulin sensitivity index, HOMA-IR and acute insulin response to glucose) indices, performed at baseline and after 12 weeks of 4 dietary interventions (high saturated fatty acid (SFA), high monounsaturated fatty acid (MUFA), low-fat and low-fat-high-n3 polyunsaturated fatty acid (PUFA)) in 486 subjects with MetS. Carriers of the minor A allele of rs12691 had altered disposition index (p = 0.0003), lower acute insulin response (p = 0.005) and a lower insulin sensitivity index (p = 0.025) indicating a lower insulin sensitivity and a lower insulin secretion, at baseline and at the end of the diets. Furthermore, A allele carriers displayed lower HDL concentration. CONCLUSION: The presence of the A allele of rs12691 influences glucose metabolism of MetS patients.
Assuntos
Glicemia/metabolismo , Proteínas Estimuladoras de Ligação a CCAAT/genética , Suplementos Nutricionais , Síndrome Metabólica/genética , Polimorfismo de Nucleotídeo Único , Adiponectina/sangue , Adulto , Idoso , Alelos , Glicemia/análise , Índice de Massa Corporal , Peso Corporal , DNA/genética , DNA/isolamento & purificação , Gorduras na Dieta/administração & dosagem , Jejum , Ácidos Graxos/administração & dosagem , Ácidos Graxos Monoinsaturados/administração & dosagem , Ácidos Graxos Ômega-3/administração & dosagem , Feminino , Genótipo , Humanos , Insulina/sangue , Insulina/metabolismo , Resistência à Insulina , Secreção de Insulina , Leptina/sangue , Metabolismo dos Lipídeos/genética , Masculino , Síndrome Metabólica/sangue , Pessoa de Meia-Idade , Resistina/sangue , Triglicerídeos/sangueRESUMO
SCOPE: Heating during the process of cooking alters the chemical properties of foods and may affect subsequent postprandial inflammation. We tested the effects of four meals rich in different oils subjected to heating on the postprandial inflammatory metabolism of peripheral blood mononuclear cells (PBMCs). METHODS AND RESULTS: Twenty obese participants received four breakfasts following a randomized crossover design, consisting of milk and muffins made with different oils (virgin olive oil (VOO), sunflower oil (SFO), and a mixture of seeds oil (SFO/canola oil) with added either dimethylpolysiloxane (SOD), or natural antioxidants from olive mill wastewater alperujo (phenols; SOP)), previously subjected to 20 heating cycles. Postprandial inflammatory status in PBMCs was assessed by the activation of nuclear NF-κB, the concentration in cytoplasm of the NF-κB inhibitor (IκB-α), the mRNA levels of NF-κB subunits and activators (p65, IKKß, and IKKα) and other inflammatory molecules (TNF-α, IL-1ß, IL-6, MIF, and JNK), and lipopolysaccharide (LPS) levels. VOO and SOP breakfasts reduced NF-κB activation, increased IκB-α, and decreased LPS plasma concentration. SFO increased IKKα, IKKß, p65, IL-1b, IL-6, MIF, and JNK mRNA levels, and plasma LPS. CONCLUSION: Oils rich in phenols, whether natural (VOO) or artificially added (SOP), reduce postprandial inflammation, compared with seed oil (sunflower).
Assuntos
Antioxidantes/administração & dosagem , Ácidos Graxos Monoinsaturados/administração & dosagem , Obesidade/metabolismo , Fenol/administração & dosagem , Óleos de Plantas/administração & dosagem , Estudos Cross-Over , Dimetilpolisiloxanos/metabolismo , Ácidos Graxos Monoinsaturados/química , Manipulação de Alimentos/métodos , Temperatura Alta , Humanos , Quinase I-kappa B/sangue , Proteínas I-kappa B/sangue , Inflamação/tratamento farmacológico , Interleucina-1beta/sangue , Interleucina-6/sangue , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Lipopolissacarídeos/sangue , Pessoa de Meia-Idade , Inibidor de NF-kappaB alfa , NF-kappa B/sangue , Obesidade/fisiopatologia , Azeite de Oliva , Óleos de Plantas/química , Período Pós-Prandial , Óleo de Brassica napus , Óleo de Girassol , Fator de Necrose Tumoral alfa/metabolismoRESUMO
OBJECTIVE: Dietary changes are major factor in determining cardiovascular risk. We assessed the effects of isoenergetic diets with different fat quantity and quality on the incidence and regression of the metabolic syndrome (MetS) from the LIPGENE project. METHODS AND DESIGN: Clinical intervention study: the patients (n=337) were randomly assigned to one of four diets for 12 weeks each: two high fat diets, one rich in saturated fat (HSFA) and the other rich in monounsaturated fat (HMUFA), and two low fat diets, one high in complex carbohydrates (LFHCC) supplemented with 1.24g/day of long-chain n-3 polyunsaturated fatty acids (LFHCC n-3) and the other LFHCC diet with placebo (LFHCC). MEASUREMENTS: the effects on MetS risk criteria were recorded before and after the intervention period. RESULTS: An enlarged waist circumference (≥88cm for women and ≥102cm for men) was present among 95% of the participants, 88% had elevated blood pressure (>130/85mm Hg or antihypertensive drugs), 77% had elevated fasting plasma glucose (≥5.55mmol/L), 51% were hypertriacylglycerolemic (≥1.7mmol/L), and 72% had low HDL cholesterol (<1.0mmol/L for men, and <1.3mmol/L for women). The prevalence of enlarged waist circumference, hypertension and hypertriacylglycerolemia were reduced after the LFHCC n-3 diet (p<0.05). Thus the prevalence of MetS fell by 20.5% after LFHCC n-3 diet compared with the HSFA (10.6%), HMUFA (12%) diet or LFHCC (10.4%) diets (p<0.028). CONCLUSIONS: The consumption of a low-fat high-carbohydrate supplemented with n-3 diet reduced the risk of MetS as compared with isoenergetic high-fat (HSFA and HMUFA) and LFHCC diets.
Assuntos
Dieta com Restrição de Gorduras , Ácidos Graxos Ômega-3/metabolismo , Síndrome Metabólica/metabolismo , Síndrome Metabólica/prevenção & controle , Adulto , Idoso , Pressão Sanguínea , Doenças Cardiovasculares/metabolismo , Europa (Continente) , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Placebos , Prevalência , RiscoRESUMO
BACKGROUND AND AIMS: Previous evidence suggests that dietary fat could influence the composition and size of triacylglycerols-rich lipoproteins (TRL). In a controlled intervention study on healthy subjects, we evaluated the influence of 3 dietary interventions, with different types of fat on postprandial TRL particle size and number. METHODS AND RESULTS: Volunteers followed three different diets for four weeks each, according to a randomized crossover design. Western diet: 15% protein, 47% carbohydrates (CHO), 38% fat (22% saturated fatty acid (SFA)); Mediterranean diet: 15% protein, 47% CHO, 38% fat (24% monounsaturated fatty acid (MUFA)); high CHO enriched with ALNA diet: 15% protein, 55% CHO, <30% fat (8% polyunsaturated fatty acid (PUFA)). After a 12-h fast, volunteers consumed a breakfast with 1g fat and 7 mg cholesterol per kg body weight and a fat composition similar to that consumed in each of the diets: Butter meal: 35% SFA; Olive oil meal: 36% MUFA; Walnut meal: 16% PUFA, 4% α-linolenic acid. Tryglicerides (TG) in TRL (large and small TRL) were determined by ultracentrifugation and size and number of lipoprotein particles were measured with Nuclear Magnetic Resonance Spectroscopy at different time points. The olive oil meal reduced the number of total TRL postprandial particles compared with the other meals (P=0.002). Moreover, the olive oil meal also increased the TRL particle size compared with the walnut meal (P=0.001). CONCLUSION: Our data showed that short-term intake of the Mediterranean diet and the acute intake of an olive oil meal lead to the formation of a reduced number and higher-size TRL particle compared with other fat sources. These novel findings have implications for understanding the postprandial lipoprotein mechanisms, and could favour the lower cardiovascular risk in Mediterranean countries.
Assuntos
Gorduras na Dieta/farmacologia , Lipoproteínas/sangue , Período Pós-Prandial/fisiologia , Triglicerídeos/sangue , Índice de Massa Corporal , Manteiga , VLDL-Colesterol/sangue , Estudos Cross-Over , Dieta , Dieta Mediterrânea , Carboidratos da Dieta/farmacologia , Ácidos Graxos/farmacologia , Humanos , Juglans , Lipídeos/sangue , Espectroscopia de Ressonância Magnética , Masculino , Azeite de Oliva , Tamanho da Partícula , Óleos de Plantas , Ultracentrifugação , Adulto JovemRESUMO
BACKGROUND: Excessive energy intake and obesity lead to the metabolic syndrome (MetS). Dietary saturated fatty acids (SFAs) may be particularly detrimental on insulin sensitivity (SI) and on other components of the MetS. OBJECTIVE: This study determined the relative efficacy of reducing dietary SFA, by isoenergetic alteration of the quality and quantity of dietary fat, on risk factors associated with MetS. DESIGN: A free-living, single-blinded dietary intervention study. SUBJECTS AND METHODS: MetS subjects (n = 417) from eight European countries completed the randomized dietary intervention study with four isoenergetic diets distinct in fat quantity and quality: high-SFA; high-monounsaturated fatty acids and two low-fat, high-complex carbohydrate (LFHCC) diets, supplemented with long chain n-3 polyunsaturated fatty acids (LC n-3 PUFAs) (1.2 g per day) or placebo for 12 weeks. SI estimated from an intravenous glucose tolerance test (IVGTT) was the primary outcome measure. Lipid and inflammatory markers associated with MetS were also determined. RESULTS: In weight-stable subjects, reducing dietary SFA intake had no effect on SI, total and low-density lipoprotein cholesterol concentration, inflammation or blood pressure in the entire cohort. The LFHCC n-3 PUFA diet reduced plasma triacylglycerol (TAG) and non-esterified fatty acid concentrations (P < 0.01), particularly in men. CONCLUSION: There was no effect of reducing SFA on SI in weight-stable obese MetS subjects. LC n-3 PUFA supplementation, in association with a low-fat diet, improved TAG-related MetS risk profiles.
Assuntos
Gorduras na Dieta/administração & dosagem , Comportamento Alimentar/fisiologia , Resistência à Insulina/fisiologia , Síndrome Metabólica/prevenção & controle , Obesidade/dietoterapia , Dieta com Restrição de Gorduras/métodos , Gorduras na Dieta/metabolismo , Ingestão de Energia/fisiologia , Europa (Continente) , Ácidos Graxos/administração & dosagem , Ácidos Graxos/efeitos adversos , Ácidos Graxos Insaturados/administração & dosagem , Feminino , Glicerol/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/metabolismo , Fatores de RiscoRESUMO
Olive oil (OO) is the most representative food of the traditional Mediterranean Diet (MedDiet). Increasing evidence suggests that monounsaturated fatty acids (MUFA) as a nutrient, OO as a food, and the MedDiet as a food pattern are associated with a decreased risk of cardiovascular disease, obesity, metabolic syndrome, type 2 diabetes and hypertension. A MedDiet rich in OO and OO per se has been shown to improve cardiovascular risk factors, such as lipid profiles, blood pressure, postprandial hyperlipidemia, endothelial dysfunction, oxidative stress, and antithrombotic profiles. Some of these beneficial effects can be attributed to the OO minor components. Therefore, the definition of the MedDiet should include OO. Phenolic compounds in OO have shown antioxidant and anti-inflammatory properties, prevent lipoperoxidation, induce favorable changes of lipid profile, improve endothelial function, and disclose antithrombotic properties. Observational studies from Mediterranean cohorts have suggested that dietary MUFA may be protective against age-related cognitive decline and Alzheimer's disease. Recent studies consistently support the concept that the OO-rich MedDiet is compatible with healthier aging and increased longevity. In countries where the population adheres to the MedDiet, such as Spain, Greece and Italy, and OO is the principal source of fat, rates of cancer incidence are lower than in northern European countries. Experimental and human cellular studies have provided new evidence on the potential protective effect of OO on cancer. Furthermore, results of case-control and cohort studies suggest that MUFA intake including OO is associated with a reduction in cancer risk (mainly breast, colorectal and prostate cancers).
Assuntos
Dieta Mediterrânea , Saúde , Óleos de Plantas , Envelhecimento/psicologia , Doenças Cardiovasculares/epidemiologia , Doença Crônica , Cognição/fisiologia , Consenso , Diabetes Mellitus/epidemiologia , Expectativa de Vida , Síndrome Metabólica/epidemiologia , Neoplasias/epidemiologia , Obesidade/epidemiologia , Azeite de Oliva , Óleos de Plantas/química , Medição de Risco , Fatores de RiscoRESUMO
Traditional cardiovascular risk factors are associated with endothelial dysfunction. The vascular endothelium plays a key role in local vascular tone regulation and can be modulated by dietary fat. We propose to determine the chronic effect of three diets with different fat compositions on postprandial endothelial function and inflammatory biomarkers. Twenty healthy men followed three 4-week diets in a randomised cross-over design: a Western diet, rich in saturated fat (22% SFA, 12% MUFA and 0.4% alpha-linolenic acid (ALA), all fractions are % of energy); a Mediterranean diet, rich in MUFA ( < 10 % SFA, 24 % MUFA and 0.4% ALA); a low-fat diet enriched in ALA ( < 10% SFA, 12% MUFA and 2% ALA). At the end of each dietary period all subjects underwent a postprandial study. Plasma concentrations of lipid parameters, soluble intercellular cell-adhesion molecule-1, soluble vascular cell-adhesion molecule-1 (sVCAM-1), nitrates and nitrites (NOx) and endothelial function studied by laser Doppler were examined at 0, 2, 4, 6 and 8 h. The endothelium-dependent vasodilatory response was greater 4 h after the ingestion of the MUFA-rich diet than after the SFA or ALA low-fat diets (P = 0.031). The 4 h postprandial plasma sVCAM-1 levels were lower after the MUFA meals than after the ALA low-fat diet (P = 0.043). The bioavailability of NOx was higher following the MUFA diet than after the SFA and ALA low-fat diets (P = 0.027). We found no differences in the other parameters measured. Chronic ingestion of a Mediterranean diet avoids the postprandial deterioration of endothelial function associated with Westernised diets in healthy individuals.
Assuntos
Dieta Mediterrânea , Gorduras na Dieta/farmacologia , Endotélio Vascular/efeitos dos fármacos , Óleos de Plantas/farmacologia , Ácido alfa-Linolênico/farmacologia , Adolescente , Adulto , Colesterol/sangue , Estudos Cross-Over , Dieta com Restrição de Gorduras , Gorduras na Dieta/administração & dosagem , Endotélio Vascular/fisiologia , Humanos , Mediadores da Inflamação/sangue , Molécula 1 de Adesão Intercelular/sangue , Masculino , Fenômenos Fisiológicos da Nutrição/fisiologia , Azeite de Oliva , Período Pós-Prandial/fisiologia , Triglicerídeos/sangue , Molécula 1 de Adesão de Célula Vascular/sangue , Vasodilatação , Adulto JovemRESUMO
Existen diferentes formas de rehabilitación de coronas sobre implantes adyacentes en un tramo edéntulo. Las opciones que pueden encontrarse son la de restaurar con varias coronas unitarias, o bien unir esas coronas en una sola prótesis. Material y Método: Se llevó a cabo una búsqueda bibliográfica a través de bases de datos en revistas especializadas de Odontología. Resultados: En la bibliografía revisada se observa que existen defensores y detractores de cada una de las técnicas, basándose cada autor en distintos estudios y argumentos. Discusión: Se encontraron ventajas e inconvenientes en ambas opciones prostodóncicas, valorando en base a éstos cuándo utilizar cada una de las técnicas propuestas. Conclusiones: Cuando las condiciones son idóneas, se considera adecuada la restauración con coronas individuales; por otro lado cuando existan condiciones adversas (implantes cortos, hueso de mala calidad, carga inmediata o factores oclusales no adecuados), en las que el reparto de fuerzas pueda comprometer el pronóstico de la restauración, la ferulización será el tratamiento de elección (AU)
There are different methods of crown rehabilitation refering to implants adjacent in edentulous sites. The options can be: rehabilitation with several single crowns or the splinting of the crowns in the prostheses. Material and method: A bibliographical research through the data base of the U.C.M. library and a review of clinical files of patients treated under the title implant-prostheses has been carried out. Results: There are supporters and non-supporters of each technique, based on different arguments and studies. Discussion: Advantages and inconvenients have been found in each method, taking these into consideration when it comes to using the appropriate restoration. Conclusions: When conditions are suitable, the implants can be restored by using single crowns. On the other hand, when there are no ideal factors (short implants, low bone quality, early loading, adverse oclussal factors) the use of splinting crowns will be more appropriate (AU)
Assuntos
Humanos , Coroas/tendências , Implantes Dentários/tendências , Ferula , Restauração Dentária Permanente/métodos , Implantes Dentários para Um Único DenteRESUMO
OBJECTIVE: Central obesity is associated with insulin resistance through factors that are not fully understood. We studied the effects of three different isocaloric diets on body fat distribution, insulin sensitivity, and peripheral adiponectin gene expression. RESEARCH DESIGN AND METHODS: Eleven volunteers, offspring of obese type 2 diabetic patients with abdominal fat deposition, were studied. These subjects were considered insulin resistant as indicated by Matsuda index values <4 after an oral glucose tolerance test, and they maintained A1C <6.5% without therapeutic intervention. All subjects underwent three dietary periods of 28 days each in a crossover design: 1) diet enriched in saturated fat (SAT), 2) diet rich in monounsaturated fat (MUFA) (Mediterranean diet), and 3) diet rich in carbohydrates (CHOs). RESULTS: Weight, body composition, and resting energy expenditure remained unchanged during the three sequential dietary periods. Using dual-energy X-ray absorptiometry we observed that when patients were fed a CHO-enriched diet, their fat mass was redistributed toward the abdominal depot, whereas periphery fat accumulation decreased compared with isocaloric MUFA-rich and high-SAT diets (ANOVA P < 0.05). Changes in fat deposition were associated with decreased postprandial mRNA adiponectin levels in peripheral adipose tissue and lower insulin sensitivity index values from a frequently sampled insulin-assisted intravenous glucose tolerance test in patients fed a CHO-rich diet compared with a MUFA-rich diet (ANOVA P < 0.05). CONCLUSIONS: An isocaloric MUFA-rich diet prevents central fat redistribution and the postprandial decrease in peripheral adiponectin gene expression and insulin resistance induced by a CHO-rich diet in insulin-resistant subjects.
Assuntos
Gordura Abdominal/efeitos dos fármacos , Adiponectina/biossíntese , Carboidratos da Dieta/farmacologia , Ácidos Graxos Monoinsaturados/farmacologia , Resistência à Insulina/fisiologia , Adiposidade/efeitos dos fármacos , Idoso , Composição Corporal , Peso Corporal , Estudos Cross-Over , Gorduras Insaturadas na Dieta , Metabolismo Energético , Feminino , Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Período Pós-PrandialRESUMO
1. Ageing represents a great concern in developed countries because the number of people involved and the pathologies related with it, like atherosclerosis, morbus Parkinson, Alzheimer's disease, vascular dementia, cognitive decline, diabetes and cancer. 2. Epidemiological studies suggest that a Mediterranean diet (which is rich in virgin olive oil) decreases the risk of cardiovascular disease. 3. The Mediterranean diet, rich in virgin olive oil, improves the major risk factors for cardiovascular disease, such as the lipoprotein profile, blood pressure, glucose metabolism and antithrombotic profile. Endothelial function, inflammation and oxidative stress are also positively modulated. Some of these effects are attributed to minor components of virgin olive oil. Therefore, the definition of the Mediterranean diet should include virgin olive oil. 4. Different observational studies conducted in humans have shown that the intake of monounsaturated fat may be protective against age-related cognitive decline and Alzheimer's disease. 5. Microconstituents from virgin olive oil are bioavailable in humans and have shown antioxidant properties and capacity to improve endothelial function. Furthermore they are also able to modify the haemostasis, showing antithrombotic properties. 6. In countries where the populations fulfilled a typical Mediterranean diet, such as Spain, Greece and Italy, where virgin olive oil is the principal source of fat, cancer incidence rates are lower than in northern European countries. 7. The protective effect of virgin olive oil can be most important in the first decades of life, which suggests that the dietetic benefit of virgin olive oil intake should be initiated before puberty, and maintained through life. 8. The more recent studies consistently support that the Mediterranean diet, based in virgin olive oil, is compatible with a healthier ageing and increased longevity. However, despite the significant advances of the recent years, the final proof about the specific mechanisms and contributing role of the different components of virgin olive oil to its beneficial effects requires further investigations.
Assuntos
Doenças Cardiovasculares/prevenção & controle , Dieta Mediterrânea , Neoplasias/prevenção & controle , Óleos de Plantas , Envelhecimento/efeitos dos fármacos , Gorduras Insaturadas na Dieta/farmacologia , Medicina Baseada em Evidências , Humanos , Azeite de Oliva , Estresse Oxidativo/efeitos dos fármacos , Óleos de Plantas/química , Óleos de Plantas/farmacologiaRESUMO
BACKGROUND: Cholesterol ester transfer protein (CETP) mediates the transfer of cholesteryl esters from HDL to apolipoprotein (apo) B-containing lipoproteins. The possible atherogenic role of this protein is controversial. Diet may influence plasma CETP concentrations. OBJECTIVE: The objective was to determine whether the changes in plasma lipids observed after consumption of 2 lipid-lowering diets are associated with changes in plasma CETP concentrations. DESIGN: : We studied 41 healthy, normolipidemic men over 3 consecutive 4-wk dietary periods: a saturated fatty acid-rich diet (SFA diet: 38% fat, 20% saturated fat), a National Cholesterol Education Program Step I diet (NCEP Step I diet: 28% fat, 10% saturated fat), and a monounsaturated fatty acid-rich diet (MUFA diet: 38% fat, 22% monounsaturated fat). Cholesterol content (27.5 mg/MJ) was kept constant during the 3 periods. Plasma concentrations of total, LDL, and HDL cholesterol; triacylglycerol; apo A-I and B; and CETP were measured at the end of each dietary period. RESULTS: Compared with the SFA diet, both lipid-lowering diets significantly decreased plasma total and LDL cholesterol, apo B, and CETP. Only the NCEP Step I diet lowered plasma HDL cholesterol. Positive, significant correlations were found between plasma CETP and total (r = 0.3868, P < 0.0001) and LDL (r = 0.4454, P < 0.0001) cholesterol and also between changes in CETP concentrations and those of total (r = 0.4543, P < 0.0001) and LDL (r = 0.4554, P < 0.0001) cholesterol. CONCLUSIONS: The isoenergetic substitution of a high-saturated fatty acid diet with an NCEP Step I or a high-monounsaturated fatty acid diet decreases plasma CETP concentrations.
Assuntos
Proteínas de Transporte/sangue , Ésteres do Colesterol/metabolismo , Dieta com Restrição de Gorduras , Gorduras Insaturadas na Dieta/administração & dosagem , Ácidos Graxos Monoinsaturados/administração & dosagem , Glicoproteínas , Adulto , Análise de Variância , Proteínas de Transferência de Ésteres de Colesterol , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Humanos , Masculino , Valores de Referência , Triglicerídeos/sangueRESUMO
UNLABELLED: Most experts, specially from Anglo-Saxon countries, recommend a low fat diet in order to prevent cardiovascular diseases. However, mortality rate by ischemic cardiopathy is low in Mediterranean countries, probably because of the consumption of a Mediterranean diet, with a high level of monounsaturated fats provided by the olive oil. We have conducted this study in order to investigate the possible influence of this kind of diet on the oxidation of LDL in vitro, the key element for the development of atherosclerosis. PATIENTS AND METHODS: 41 healthy male subjects were submitted to three consecutive 4-week diets. The first was a saturated fat-rich diet (SAT diet, 38% fat, 20% saturated). This was followed by a low fat diet (NCEP-I, 28% fat, 10% saturated) and after that a Mediterranean diet (38% fat, 22% monounsaturated fat). Plasma levels of total cholesterol, LDL-c, HDL-c, triglycerides, apolipoproteins A-I and B, -tocopherol, and the in vitro susceptibility to oxidation of LDL particles. Both hypolipidemic diets produced a significant decrease in total cholesterol, LDL-c, and apo-B plasma levels. However, it was only the NCEP-I diet that revealed a decrease in the HDL-c. The shift from a saturated fat-rich diet, or a diet rich in carbohydrates, to a Mediterranean diet increased the resistance of LDL particles to oxidation increasing the lag time period (p < 0.038), and decreasing (p < 0.001) the progression rate of the curve of oxidation of LDL. Our results point out two positive consequences of the consumption of a Mediterranean diet by healthy young males, compared with the low fat diet recommended by most Anglo-Saxon experts. On the one hand, the Mediterranean diet increases HDL-c plasma levels, and on the other hand, it decreases the susceptibility of LDL to oxidation. This is why the Mediterranean diet must be recommended in order to prevent cardiovascular diseases.
Assuntos
LDL-Colesterol/metabolismo , Dieta , Gorduras na Dieta , Óleos de Plantas , Adulto , Doenças Cardiovasculares/prevenção & controle , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Dieta com Restrição de Gorduras , Gorduras Insaturadas na Dieta , Humanos , Masculino , Região do Mediterrâneo , Azeite de Oliva , OxirreduçãoRESUMO
OBJECTIVE: Two dietary regimens recommended for the reduction of coronary risk, by way of their effects on lipid profile, are the diet low in saturated fat and a diet rich in monounsaturated fats (MUFA). However the effects of these diets on carbohydrate metabolism in healthy subjects are not well known. The objective of this study was to compare the effect of both diets on various parameters of carbohydrate metabolism. METHODS: 41 healthy young males were submitted to 3 consecutive diets, each for a duration of 4 weeks. The first diet was rich in saturated fat (SAT) (38% fat, 20% saturated). The second was rich in carbohydrates following the recommendations of the NCEP-I (National Cholesterol Education Program type I) (28% fat, 47% carbohydrates). The last one was a diet rich in monounsaturated fatty acids (38% fat, 22% MUFA). At the end of each dietary period, blood pressure (BP) and blood levels of glucose, insulin and free fatty acids were determined. 29 subjects were also submitted to an oral glucose tolerance test (OGTT) at the end of each diet. RESULTS: The SAT diet induced the highest levels of insulin after the OGTT. The consumption of the MUFA diet determined the lowest levels of fasting blood glucose (-0.60 mmol/l [13%], p < 0.0002), insulin (-9 microUl/ml [47%], p < 0.0002) and free fatty acids (-0.11 mmol/l [24%], p = 0.006), compared to the NCEP-I diet. Systolic and diastolic blood pressure were higher in the NCEP-I diet than during the other periods (SBP: +6 mmHg compare with SAT [5%], p = 0.0001; and +5 mmHg compare with MUFA [4%], p = 0.0001; DBP: +20 mmHg compare with MUFA [27%], p = 0.0001) and +6 mmHg compared with SAT [8%], p = 0.0001). CONCLUSION: Of the diets most commonly used for the treatment and prevention of arteriosclerosis, a diet rich in monounsaturated fats is the most beneficial for the healthy population from the point of view of carbohydrate metabolism and blood pressure.
Assuntos
Pressão Sanguínea/fisiologia , Carboidratos/sangue , Gorduras Insaturadas na Dieta/administração & dosagem , Ácidos Graxos Monoinsaturados/administração & dosagem , Adulto , Análise de Variância , Arteriosclerose/prevenção & controle , Glicemia/análise , Gorduras Insaturadas na Dieta/sangue , Ácidos Graxos Monoinsaturados/sangue , Ácidos Graxos não Esterificados/sangue , Humanos , Insulina/sangue , Resistência à Insulina/fisiologia , Masculino , Valores de Referência , Fatores de TempoRESUMO
Lipid response to dietary fat is highly variable among individuals of a population. The aim of this study was to establish whether being overweight is one of the factors that determines this response. Forty-one non-obese healthy men were divided into two groups according to body mass index as follows: controls, <25 kg/m2; overweight, >25 kg/m2 but <30 kg/m2. After consuming a saturated fat-rich diet (SAT diet: 38% fat, 20% saturated) for 4 wk, subjects were switched to a low fat diet [National Cholesterol Education Program (NCEP)-I diet: 28% fat, 10% saturated] for 4 wk and then to a monounsaturated fat-rich diet (MUFA diet: 38% fat, 22% monounsaturated) for 4 wk. Data were analyzed by Student's t test and two-way ANOVA for repeated measures. After consuming the NCEP-I diet, the overweight subjects had a smaller decrease relative to the SAT diet period in plasma total cholesterol [-0.30 vs. -0.67 mmol/L (-7 vs. -16%), P < 0.02] and low density lipoprotein-cholesterol concentrations [-0.24 vs. -0.55 mmol/L (-9 vs. -21%), P < 0.04] than controls. However, in the overweight subjects, the MUFA diet produced a greater decrease in plasma triglycerides than in the controls relative to the SAT diet period [-0.36 vs. -0.03 mmol/L (-26 vs. -4%), P < 0.006] and to the NCEP-I diet period [-0.29 vs. 0. 01 mmol/L (-22 vs. 1%), P < 0.01). Plasma cholesterol concentrations changed to a lesser extent, and triglyceride concentration to a greater extent, in overweight but non-obese young men than in those of normal weight in response to changes in dietary fat composition. Our data suggest that in the diet treatment of obese hyperlipemic subjects, it is more important for them to lose weight than to change the fat composition of their diets.
Assuntos
Índice de Massa Corporal , Dieta com Restrição de Gorduras , Lipídeos/sangue , Adulto , Apolipoproteína A-I/metabolismo , Apolipoproteínas B/sangue , Colesterol/sangue , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Gorduras Insaturadas na Dieta/administração & dosagem , Ácidos Graxos Monoinsaturados/administração & dosagem , Humanos , Masculino , Triglicerídeos/sangueRESUMO
Previous studies have shown that the A to G transition occurring at position -75 bp upstream of the transcriptional start site in the human apolipoprotein A-I gene may affect plasma high density lipoprotein cholesterol (HDL-C) levels and low density lipoprotein cholesterol (LDL-C) response to changes in amount of dietary fat. We have examined the response to dietary fat saturation as a function of this mutation in 50 men and women. Subjects were first fed a saturated (SAT) fat diet (35% fat, 17% SAT) for 28 days, followed by a diet rich in monounsaturated fatty (MUFA) acids (35% fat, 22% MUFA) for 35 days and a diet rich in polyunsaturated (PUFA) fat (35% fat, 13% PUFA) for 35 days. All meals were prepared and consumed at the study sites. Lipoproteins were measured at the end of each diet period. The allele frequency for the A allele was 0.13. Subjects carrying the A allele had higher plasma cholesterol, LDL-C and triglyceride levels than those homozygotes for the G allele. As compared to the SAT diet, a PUFA diet induced significantly greater plasma total (P = 0.003) and LDL-C decreases (P = 0.001) in G/A women (-1.62 and -1.32 mmol/l, respectively) than in G/G subjects (-0.87 and -0.74 mmol/l for plasma and LDL-C, respectively). Multiple regression analysis demonstrated that in women, the variability in LDL-C response from a diet rich in SAT fat to a diet rich in PUFA was primarily due to LDL-C levels (during the SAT phase), accounting for 55.1% of the variance, waist to hip ratio (W/H; 11.4%) and the G/A polymorphism (10%). Whereas in men the major determinant of this response was smoking (21.4%). In conclusion, the G/A polymorphism appears to have a small but significant effect on plasma LDL-C responsiveness to changes in dietary fat saturation specially in women.
Assuntos
Apolipoproteína A-I/genética , LDL-Colesterol/sangue , Gorduras na Dieta/administração & dosagem , Hipercolesterolemia/genética , Mutação , Regiões Promotoras Genéticas/genética , Adulto , DNA/análise , Primers do DNA/química , Ácidos Graxos Monoinsaturados/administração & dosagem , Ácidos Graxos Insaturados/administração & dosagem , Feminino , Seguimentos , Humanos , Hipercolesterolemia/sangue , Hipercolesterolemia/dietoterapia , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Polimorfismo Genético , Período Pós-Prandial , Triglicerídeos/sangueRESUMO
The effects on plasma lipid concentrations of two oleic acid-rich diets, prepared with two different plant oils--olive oil and sunflower oil high in monounsaturated fatty acids (MUFAs)-- were compared with a National Cholesterol Education Program (NCEP) I diet. Twenty-one healthy, normolipidemic, young males consumed an NCEP-I diet (30% of energy as fat) during a 25-d period. Subjects were then assigned to two 4-wk study periods, according to a randomized, crossover design. Group one was placed on an olive oil-enriched diet (40% fat, 22% MUFAs), followed by a 4-wk period of a sunflower oil-enriched diet (40% fat, 22% MUFAs). In group two, the order of the diets was reversed. Both MUFA dietary periods resulted in an increase in high-density-lipoprotein (HDL) cholesterol (7% for the olive oil diet and 4% for the sunflower oil diet) and in apolipoprotein (apo) A-I (9% for both) compared with the NCEP-I diet. Low-density-lipoprotein (LDL) cholesterol and apo B concentrations (x +/- SEM) were lower (P < 0.05) during the sunflower oil diet (2.40 +/- 0.11 mmol/L, 0.85 +/- 0.04 mg/L) than during the olive oil diet (2.64 +/- 0.15 mmol/L, 0.93 +/- 0.05 mg/L). No significant differences were observed in these variables between the sunflower oil and NCEP-I (2.48 +/- 0.13 mmol/L, 0.89 +/- 0.04 mg/L) diets.(ABSTRACT TRUNCATED AT 250 WORDS)