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1.
Public Health Nutr ; 20(7): 1322-1330, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28003037

RESUMO

OBJECTIVE: To characterize the multiple dimensions and benefits of the Mediterranean diet as a sustainable diet, in order to revitalize this intangible food heritage at the country level; and to develop a multidimensional framework - the Med Diet 4.0 - in which four sustainability benefits of the Mediterranean diet are presented in parallel: major health and nutrition benefits, low environmental impacts and richness in biodiversity, high sociocultural food values, and positive local economic returns. DESIGN: A narrative review was applied at the country level to highlight the multiple sustainable benefits of the Mediterranean diet into a single multidimensional framework: the Med Diet 4.0. Setting/subjects We included studies published in English in peer-reviewed journals that contained data on the characterization of sustainable diets and of the Mediterranean diet. The methodological framework approach was finalized through a series of meetings, workshops and conferences where the framework was presented, discussed and ultimately refined. RESULTS: The Med Diet 4.0 provides a conceptual multidimensional framework to characterize the Mediterranean diet as a sustainable diet model, by applying principles of sustainability to the Mediterranean diet. CONCLUSIONS: By providing a broader understanding of the many sustainable benefits of the Mediterranean diet, the Med Diet 4.0 can contribute to the revitalization of the Mediterranean diet by improving its current perception not only as a healthy diet but also a sustainable lifestyle model, with country-specific and culturally appropriate variations. It also takes into account the identity and diversity of food cultures and systems, expressed within the notion of the Mediterranean diet, across the Mediterranean region and in other parts of the world. Further multidisciplinary studies are needed for the assessment of the sustainability of the Mediterranean diet to include these new dimensions.


Assuntos
Dieta Mediterrânea/economia , Biodiversidade , Conservação dos Recursos Naturais/economia , Custos e Análise de Custo , Cultura , Dieta Saudável/economia , Abastecimento de Alimentos/economia , Comportamentos Relacionados com a Saúde , Humanos , Estilo de Vida , Modelos Econômicos , Política Nutricional/economia
2.
Br J Nutr ; 116(12): 2091-2096, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28069089

RESUMO

Lycopene (LYC) bioavailability is relatively low and highly variable, because of the influence of several factors. Recent in vitro data have suggested that dietary Ca can impair LYC micellarisation, but there is no evidence whether this can lead to decreased LYC absorption efficiency in humans. Our objective was to assess whether a nutritional dose of Ca impairs dietary LYC bioavailability and to study the mechanism(s) involved. First, in a randomised, two-way cross-over study, ten healthy adults consumed either a test meal that provided 19-mg (all-E)-LYC from tomato paste or the same meal plus 500-mg calcium carbonate as a supplement. Plasma LYC concentration was measured at regular time intervals over 7 h postprandially. In a second approach, an in vitro digestion model was used to assess the effect of increasing Ca doses on LYC micellarisation and on the size and zeta potential of the mixed micelles produced during digestion of a complex food matrix. LYC bioavailability was diminished by 83 % following the addition of Ca in the test meal. In vitro, Ca affected neither LYC micellarisation nor mixed micelle size but it decreased the absolute value of their charge by 39 %. In conclusion, a nutritional dose of Ca can impair dietary LYC bioavailability in healthy humans. This inhibition could be due to the fact that Ca diminishes the electrical charge of micelles. These results call for a thorough assessment of the effects of Ca, or other divalent minerals, on the bioavailability of other carotenoids and lipophilic micronutrients.


Assuntos
Cálcio da Dieta/efeitos adversos , Carotenoides/antagonistas & inibidores , Suplementos Nutricionais/efeitos adversos , Digestão , Frutas/química , Absorção Intestinal , Solanum lycopersicum/química , Adulto , Carbonato de Cálcio/administração & dosagem , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Carotenoides/sangue , Carotenoides/metabolismo , Estudos Cross-Over , Feminino , França/epidemiologia , Humanos , Incidência , Licopeno , Masculino , Refeições , Micelas , Valor Nutritivo , Neoplasias da Próstata/epidemiologia , Neoplasias da Próstata/etiologia , Risco , Propriedades de Superfície , Adulto Jovem
3.
Nutr Metab Cardiovasc Dis ; 23(7): 677-83, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22633793

RESUMO

BACKGROUND AND AIMS: Benefits of Mediterranean diet on MetS risk have been suggested, but overall prospective evidence in the general population is limited. For the first time, the prospective association of adherence to Mediterranean diet with the 6-y risk of MetS and its components was evaluated in a large cohort in Europe. METHODS AND RESULTS: Subjects included were participants from the Supplémentation en Vitamines et Minéraux AntioXydants (SU.VI.MAX) study. Adherence to Mediterranean diet was assessed using traditional Mediterranean diet score (MDS), an updated Mediterranean score (MED) and Mediterranean style-dietary pattern score (MSDPS) calculated from at least three 24-h records. In 3232 subjects, the association between Mediterranean diet scores and 6-y risk of MetS was evaluated. The association between Mediterranean scores and MetS components was also estimated. A lower risk of MetS was observed with increasing MED score (P-trend = 0.001) and MDS (P-trend = 0.03) in multivariate models. The adjusted odds ratios (95% Confidence Interval) for MetS risk were 0.47 (0.32-0.69) and 0.50 (0.32-0.77) in subjects in the highest versus lowest tertile of MED score and MDS, respectively. The MED score was inversely associated with waist circumference, systolic blood pressure and triglycerides, and directly associated with HDL-cholesterol. The MDS was negatively associated with waist circumference and triglycerides, and MSDPS was positively associated with HDL-cholesterol. CONCLUSIONS: All Mediterranean diet scores were associated in a potentially beneficial direction with components of MetS or MetS incidence. Our findings support that individuals should be encouraged to follow a Mediterranean dietary pattern for reduction of MetS risk.


Assuntos
Doenças Cardiovasculares/prevenção & controle , Dieta Mediterrânea , Síndrome Metabólica/prevenção & controle , Adulto , Índice de Massa Corporal , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Estudos de Coortes , Europa (Continente)/epidemiologia , Comportamento Alimentar , Feminino , Seguimentos , Humanos , Hiperlipidemias/fisiopatologia , Hipertensão/fisiopatologia , Incidência , Modelos Lineares , Modelos Logísticos , Masculino , Síndrome Metabólica/epidemiologia , Síndrome Metabólica/etiologia , Pessoa de Meia-Idade , Sobrepeso/fisiopatologia , Cooperação do Paciente , Fatores de Risco , Circunferência da Cintura
4.
Nutr Metab Cardiovasc Dis ; 23(5): 417-23, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-22269963

RESUMO

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/sangue
5.
Int J Obes (Lond) ; 35(2): 251-8, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20603626

RESUMO

BACKGROUND: The beneficial impact of the traditional Mediterranean diet pattern on adiposity is still under debate, and this has never been assessed in a developing Mediterranean country. OBJECTIVES: To assess the relationships between adherence to a traditional Mediterranean diet and adiposity indexes, that is, body mass index (BMI) and waist circumference (WC), in a sample from rural Lebanon. DESIGN: A sample of 798 adults, aged 40-60 years, was selected in continental rural areas of Lebanon for a cross-sectional study. The questionnaire included socio-demographic, anthropometric and dietary sections. The daily consumption frequencies of selected food groups, categorized as positive or negative components, were calculated based on a food frequency questionnaire. Adherence to the Mediterranean diet was assessed using six a priori scores; including the widely used Mediterranean diet score (MDS). Associations between diet scores and BMI and WC were assessed. RESULTS: Overall, the diet of the study sample only partially matched the traditional Mediterranean diet. A total of 17.0% of men and 33.7% women were obese. The MDS was negatively associated (P<0.05) with WC, but not BMI, in men and women. The constructed composite Mediterranean score combining positive components of the diet (whole cereals, vegetables, legumes and fruit, olive oil and fish) and negative components adapted to this sample (refined cereals and pastries, and liquid sweets) was consistently and negatively associated with both BMI and WC for men and women in multivariate models. A 2-point increase in that score was associated with a decrease in BMI of 0.51 and 0.78 kg m(-2) and a decrease in WC of 2.77 and 4.76 cm in men and women, respectively. CONCLUSION: The results demonstrate that a Mediterranean diet is negatively associated with obesity and visceral adiposity in a rural population of a developing Mediterranean country.


Assuntos
Adiposidade/fisiologia , Dieta Mediterrânea , Carboidratos da Dieta/administração & dosagem , Grão Comestível , Obesidade/dietoterapia , Adiposidade/etnologia , Adulto , Índice de Massa Corporal , Estudos Transversais , Carboidratos da Dieta/efeitos adversos , Grão Comestível/efeitos adversos , Comportamento Alimentar/etnologia , Feminino , Humanos , Líbano/epidemiologia , Masculino , Pessoa de Meia-Idade , Obesidade/epidemiologia , Obesidade/etnologia , Saúde da População Rural , Fatores Sexuais , Inquéritos e Questionários , Circunferência da Cintura
6.
Nutr Metab Cardiovasc Dis ; 21(9): 665-71, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20399083

RESUMO

BACKGROUND AND AIMS: The Metabolic Syndrome (MetS) is associated with increased cardiovascular risk. Circulating microparticles (MP) are involved in the pathogenesis of atherothrombotic disorders and are raised in individual with CVD. We measured their level and cellular origin in subjects with MetS and analyzed their associations with 1/anthropometric and biological parameters of MetS, 2/inflammation and oxidative stress markers. METHODS AND RESULTS: Eighty-eight subjects with the MetS according to the NCEP-ATPIII definition were enrolled in a bicentric study and compared to 27 healthy controls. AnnexinV-positive MP (TMP), MP derived from platelets (PMP), erythrocytes (ErMP), endothelial cells (EMP), leukocytes (LMP) and granulocytes (PNMP) were determined by flow cytometry. MetS subjects had significantly higher counts/µl of TMP (730.6±49.7 vs 352.8±35.6), PMP (416.0±43.8 vs 250.5±23.5), ErMP (243.8±22.1 vs 73.6±19.6) and EMP (7.8±0.8 vs 4.0±1.0) compared with controls. LMP and PNMP were not statistically different between groups. Multivariate analysis demonstrated that each criterion for the MetS influenced the number of TMP. Waist girth was a significant determinant of PMP and EMP level and blood pressure was correlated with EMP level. Glycemia positively correlated with PMP level whereas dyslipidemia influenced EMP and ErMP levels. Interestingly, the oxidative stress markers, plasma glutathione peroxydase and urinary 8-iso-prostaglandin F(2) α, independently influenced TMP and PMP levels whereas inflammatory markers did not, irrespective of MP type. CONCLUSION: Increased levels of TMP, PMP, ErMP and EMP are associated with individual metabolic abnormalities of MetS and oxidative stress. Whether MP assessment may represent a marker for risk stratification or a target for pharmacological intervention deserves further investigation.


Assuntos
Plaquetas/patologia , Micropartículas Derivadas de Células/metabolismo , Células Endoteliais/patologia , Eritrócitos/metabolismo , Síndrome Metabólica/patologia , Estresse Oxidativo , Adulto , Idoso , Biomarcadores/sangue , Plaquetas/metabolismo , Estudos de Casos e Controles , Micropartículas Derivadas de Células/patologia , Células Endoteliais/metabolismo , Feminino , Citometria de Fluxo , Humanos , Interleucina-6/sangue , Modelos Lineares , Masculino , Síndrome Metabólica/sangue , Pessoa de Meia-Idade , Fator de Necrose Tumoral alfa/sangue , Molécula 1 de Adesão de Célula Vascular/sangue
7.
Nutr Metab Cardiovasc Dis ; 20(4): 284-94, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20303720

RESUMO

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 Risco
8.
Diabet Med ; 26(7): 736-9, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19573124

RESUMO

AIMS: To determine plasma levels of apoprotein (apo) C-II and apoprotein C-III in Type 2 diabetic patients and to examine the clinical and biological factors that are associated with elevated apoC concentrations. METHODS: We measured apoC-II and apoC-III in total plasma and in non-high-density lipoprotein fractions by an immunoturbidimetric assay in 88 Caucasian Type 2 diabetic patients and in 138 healthy control subjects. RESULTS: Plasma levels of both apoC-II and apoC-III were increased in Type 2 diabetic patients. The clinical conditions associated with an increase of plasma apoC-II and apoC-III were abdominal obesity, body mass index, poor glycaemic control and lack of insulin treatment. However, when multivariate analysis was used, plasma apoCs levels correlated with triglyceride levels only. The apoC-III/apoC-II ratio was similar in the Type 2 diabetic and control subjects. CONCLUSIONS: Our study shows the parallel increase of apoC-II and C-III in Type 2 diabetic patients. This parallel increase is related to hypertriglyceridaemia only.


Assuntos
Apolipoproteínas C/sangue , Diabetes Mellitus Tipo 2/sangue , Hipertrigliceridemia/sangue , Idoso , Índice de Massa Corporal , Estudos de Casos e Controles , HDL-Colesterol/metabolismo , LDL-Colesterol/metabolismo , Diabetes Mellitus Tipo 2/terapia , Feminino , Humanos , Lipase Lipoproteica/metabolismo , Masculino , Pessoa de Meia-Idade , Obesidade
9.
Eur J Clin Nutr ; 61(10): 1145-61, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17457341

RESUMO

BACKGROUND: Postprandial lipid metabolism in humans has deserved much attention during the last two decades. Although fasting lipid and lipoprotein parameters reflect body homeostasis to some extent, the transient lipid and lipoprotein accumulation that occurs in the circulation after a fat-containing meal highlights the individual capacity to handle an acute fat input. An exacerbated postprandial accumulation of triglyceride-rich lipoproteins in the circulation has been associated with an increased cardiovascular risk. METHODS: The important number of studies published in this field raises the question of the methodology used for such postprandial studies, as reviewed. RESULTS: Based on our experiences, the present review reports and discuss the numerous methodological issues involved to serve as a basis for further works. These aspects include aims of the postprandial tests, size and nutrient composition of the test meals and background diets, pre-test conditions, characteristics of subjects involved, timing of sampling, suitable markers of postprandial lipid metabolism and calculations. CONCLUSION: In conclusion, we stress the need for standardization of postprandial tests.


Assuntos
Gorduras na Dieta/administração & dosagem , Gorduras na Dieta/metabolismo , Transtornos do Metabolismo dos Lipídeos/diagnóstico , Metabolismo dos Lipídeos/fisiologia , Área Sob a Curva , Biomarcadores , Humanos , Tamanho da Partícula , Seleção de Pacientes , Período Pós-Prandial/fisiologia
10.
Eur J Clin Nutr ; 61(10): 1167-73, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17268411

RESUMO

OBJECTIVE: (R,R,R)-alpha-tocopherol is a fat-soluble antioxidant vitamin generally ingested with other dietary antioxidants. The objective of this study was to assess whether the main dietary antioxidant classes, that is carotenoids, polyphenols, vitamin C and gamma-tocopherol, affect the intestinal absorption of alpha-tocopherol. METHODS, DESIGN AND SUBJECTS: We evaluated first the effect of different combinations of antioxidants on (R,R,R)-alpha-tocopherol absorption by a human intestinal cell line (Caco-2 clone TC7). Then we compared the effect of two doses of a dietary antioxidant (lutein) on the postprandial chylomicron alpha-tocopherol responses to an alpha-tocopherol-rich meal. Eight healthy men ate two similar meals in a random order at a 1 month interval. The meals contained 24 mg alpha-tocopherol in sunflower oil plus either 18 or 36 mg lutein. Blood samples were collected during the postprandial periods to compare chylomicron alpha-tocopherol responses. RESULTS: A mixture of polyphenols (gallic acid, caffeic acid, (+)-catechin and naringenin) and a mixture of carotenoids (lycopene, beta-carotene and lutein) significantly impaired alpha-tocopherol absorption in Caco-2 cells (P<0.001 and P<0.0001, respectively). The inhibitory effect of gamma-tocopherol was close to significance (P=0.055). In contrast, vitamin C had no significant effect (P=0.158). Naringenin was the only polyphenol that significantly impaired alpha-tocopherol absorption. Postprandial alpha-tocopherol response was weakest at the highest dose of lutein (616+/-280 nmol/l h vs 1001+/-287 nmol/l h). The observed extent of reduction (-38%, P=0.069) supported the inhibitory effect of carotenoids observed in the Caco-2 experiments. CONCLUSION: Naringenin, carotenoids and probably gamma-tocopherol can impair alpha-tocopherol absorption whereas vitamin C and phenolic acids have no effect.


Assuntos
Antioxidantes/farmacologia , Quilomícrons/química , Absorção Intestinal/efeitos dos fármacos , Luteína/farmacologia , alfa-Tocoferol/farmacocinética , Adulto , Área Sob a Curva , Ácido Ascórbico/farmacologia , Células CACO-2 , Carotenoides/farmacologia , Estudos Cross-Over , Relação Dose-Resposta a Droga , Flavonoides/farmacologia , Humanos , Masculino , Fenóis/farmacologia , Polifenóis , Período Pós-Prandial , gama-Tocoferol/farmacologia
11.
Dig Liver Dis ; 39(7): 646-53, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17531554

RESUMO

BACKGROUND/AIMS: We investigated (a) in vitro and in vivo the changes of biliary mass of the anionic peptide fraction, apolipoproteinA-I, immunoglobulin-A, albumin and cholesterol over time in the excluded gallbladder and (b) in vivo the localization in the gallbladder epithelium of the anionic peptide fraction and cholesterol absorbed from bile. METHODS: Native bile was substituted with pig bile containing radiolabeled cholesterol in the in vitro isolated intra-arterially perfused pig gallbladder (n=9) and in vivo in anestethized pigs with excluded gallbladders (n=6). The amount of cholesterol (scintillation counting) and proteins (enzyme-linked immunosorbent assay) in gallbladder bile were measured over time. The localization of the anionic peptide fraction and cholesterol absorbed from bile in the gallbladder epithelium was studied in vivo by immunohistochemistry and fluoro-phospho-imager analysis. RESULTS: The rate of biliary cholesterol disappeared from bile was a function of the initial concentration and of the biliary mass changes over time of the anionic peptide fraction, but not of that of the other biliary proteins. The anionic peptide fraction colocalized with biliary cholesterol absorbed by the gallbladder on the apical side of gallbladder epithelial cells. CONCLUSIONS: These data indirectly suggest that biliary anionic peptide fraction could favour biliary cholesterol absorption by the gallbladder epithelium.


Assuntos
Apoproteínas/análise , Bile/metabolismo , Proteínas de Ligação ao Cálcio/análise , Colesterol/análise , Epitélio/metabolismo , Vesícula Biliar/metabolismo , Absorção , Albuminas/análise , Animais , Apolipoproteína A-I/análise , Bile/química , Ensaio de Imunoadsorção Enzimática , Epitélio/química , Vesícula Biliar/química , Imunoglobulina A/análise , Técnicas In Vitro , Suínos
12.
Biochim Biophys Acta ; 620(3): 612-25, 1980 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-7195282

RESUMO

Bile salts-phosphatidylcholines-cholesterol mixed micelles, native bile, egg yolk and intralipid emulsions were used as pancreatic phospholipase A2 (EC 3.1.1.4) substrates. The enzyme activity depends on the bile salt/phosphatidylcholine molar ratio. The enzyme had a low specific activity on bile phosphatidylcholines, because of the existence in native bile of a high bile salt/phosphatidylcholine molar ratio generating unfavorable conditions of hydrolysis, as demonstrated with mixed micelles. However when the bile salt/phosphatidylcholine molar ratio from bile was decreased to 2 : 1, enzyme activity increases up to an optimum. This optimal activity was about one third that observed when the substrate was mixed micelles. Under these optimal conditions a simultaneous hydrolysis of intralipid and bile phosphatidylcholine mixture shows comparable initial hydrolysis rates. During an extended incubation, however, nearly all intralipid phosphatidylcholines and only half the bile phosphatidylcholines were hydrolyzed by pancreatic phospholipase A2. Bile salts mixture or native bile desorb a portion of the phosphatidylcholines from the intralipid emulsion in optimally hydrolysable bile salts phosphatidylcholines mixed micelles. These micelles bind about 85% of the enzyme indicating that hydrolysis occurs primarily in the micellar phase. These results are discussed in terms of fat lipolysis in vivo.


Assuntos
Pâncreas/enzimologia , Fosfatidilcolinas/metabolismo , Fosfolipases A/metabolismo , Fosfolipases/metabolismo , Animais , Apolipoproteínas/metabolismo , Bile/metabolismo , Ácidos e Sais Biliares/metabolismo , Galinhas , Gema de Ovo/metabolismo , Emulsões , Feminino , Hidrólise , Micelas , Fosfolipases A2 , Ratos , Suínos
13.
Biochim Biophys Acta ; 618(1): 106-18, 1980 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-7378424

RESUMO

We report a new technique which allows us to follow the lipolysis of monomolecular films in the presence of bile salts by using a 'zero-order' trough (Verger, R. and de Haas, G.H. (1973) Chem. Phys. Lipids 10, 127). The effects of bile salts, the bile lipoprotein complex and colipase on pancreatic lipase hydrolysis of rac-1,2-didodecanoylglycerol films were studied at different surface pressures. Taking into account previous studies, lipase activity was interpreted as a function of its degree of binding to the bile lipoprotein complex.


Assuntos
Ácidos e Sais Biliares/farmacologia , Bile/metabolismo , Lipase/metabolismo , Lipoproteínas/farmacologia , Lipossomos , Pâncreas/enzimologia , Animais , Colipases/farmacologia , Diglicerídeos , Hidrólise , Técnicas In Vitro , Cinética , Lauratos , Ratos , Suínos
14.
Biochim Biophys Acta ; 618(1): 119-28, 1980 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-7378425

RESUMO

Emulsions of natural triacylglycerols obtained with different shear forces were used to study lipase adsorption and lipolysis. The influence of the bile lipoprotein complex on these two processes was determined. Optimal lipase activity was observed to occur with a given phospholipid : triacylglycerol ratio. This ratio depended on the degree of triacylglycerol emulsification and was accompanied by maximal adsorption of the bile lipoprotein complex. These results support our previous model for pancreatic lipolysis under physiological conditions, according to which colipase controls lipase binding to the bile lipoprotein complex and the resulting association directs enzyme adsorption to the acylglycerol particle (Lairon, D., Nalbone, G., Lafont, H., Léonardi, J., Domingo, N., Hauton, J.C. and Verger, R. (1978) Biochemistry 17, 5263--5269).


Assuntos
Bile/metabolismo , Lipase/metabolismo , Lipídeos/farmacologia , Pâncreas/enzimologia , Triglicerídeos , Adsorção , Animais , Emulsões , Lipólise , Lipoproteínas/metabolismo , Modelos Biológicos , Ratos , Suínos , Triglicerídeos/metabolismo
15.
Diabetes ; 50(2): 462-9, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11272161

RESUMO

The role of postprandial insulin in the regulation of postprandial lipid metabolism is still poorly understood. The roles of hyperinsulinemia and insulin resistance in the alteration of postprandial lipid metabolism are not clear either. To improve knowledge in this area, we submitted healthy men to acute hyperinsulinemia in two different ways. In the first study, we compared in 10 men the effects of four isolipidic test meals that induce different degrees of hyperinsulinemia on postprandial lipid metabolism. Three different carbohydrate sources were compared according to their glycemic indexes (GIs; 35, 75, and 100 for white kidney bean, spaghetti, and white bread test meals, respectively); the fourth test meal did not contain any carbohydrates. Postprandial plasma insulin levels were proportional to the GIs (maximal plasma insulin concentrations: 113 +/- 16 to 266 +/- 36 pmol/l). We found a strong positive correlation during the 6-h postprandial period between apolipoprotein (apo) B-48 plasma concentration and insulin plasma concentration (r2 = 0.70; P = 0.0001). In a second study, 5 of the 10 subjects again ingested the carbohydrate-free meal, but during a 3-h hyperinsulinemic- (550 +/- 145 pmol/l plasma insulin) euglycemic (5.5 +/- 0.8 mmol/l plasma glucose) clamp. A biphasic response was observed with markedly reduced levels of plasma apoB-48 during insulin infusion, followed by a late accumulation of plasma apoB-48 and triglycerides. Overall, the data obtained showed that portal and peripheral hyperinsulinism delays and exacerbates postprandial accumulation of intestinally derived chylomicrons in plasma and thus is involved in the regulation of apoB-48-triglyceride-rich lipoprotein metabolism, in the absence of insulin-resistance syndrome.


Assuntos
Apolipoproteínas B/sangue , Hiperinsulinismo/sangue , Lipoproteínas/sangue , Triglicerídeos/sangue , Doença Aguda , Adulto , Apolipoproteína B-48 , Glicemia/análise , Alimentos , Humanos , Insulina/sangue , Lipídeos/sangue , Masculino , Período Pós-Prandial/fisiologia , Valores de Referência
16.
Diabetes Metab ; 31(1): 69-77, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15803116

RESUMO

OBJECTIVES: The present study examines the kinetic of plasma triacylglycerol (TAG) after sequential ingestion of lunch and dinner as well as the contribution of dietary fat ingested at lunch to subsequent post-dinner TAG composition. METHOD: Six healthy subjects were included. After standardized breakfast (7: 30AM), 2 mixed meals with fat loads composed of 44 g olive oil (rich in oleic acid) at lunch (12PM) and 44 g sunflower oil (rich in linoleic acid) at dinner (7PM) were ingested. [1-13C] palmitate was added in lunch only. Plasma TAG and chylomicron-TAG (CMTAG) levels were measured sequentially after meals. [1-13C] palmitate enrichment and concentrations of oleic acid and linoleic acid were measured in all lipid fractions. RESULT: Post-dinner plasma TAG peak was delayed as compared to lunch (3 hours vs 1 hour, p=0.002) whereas the magnitude of the postprandial peaks was not significantly different between lunch and dinner (2.4+/-0.3 vs 2.0+/-0.4 mmol/L, p=0.85). [1-13C] palmitate enrichment was maximal 5 hours after lunch in all lipid fractions and decreased slowly thereafter. After dinner ingestion, the rate of decline of [1-13C] palmitate enrichment plateaued during the first 60 minutes. Oleic acid increased slightly and immediately after dinner and remained the predominant fatty acid in all lipid fractions during the first hour after dinner. A delayed peak of plasma and CM-TAG was observed after dinner as compared to lunch without difference in the magnitude of peaks. CONCLUSION: The contribution of dietary fat ingested at lunch to post-dinner lipemia is confirmed despite the relatively long lasting interval between the 2 meals (7 h) and the absence of any early peak of plasma TAG after dinner.


Assuntos
Gorduras na Dieta , Período Pós-Prandial , Triglicerídeos/sangue , Adulto , Ritmo Circadiano , Humanos , Masculino , Azeite de Oliva , Óleos de Plantas , Valores de Referência , Óleo de Girassol
17.
Eur J Clin Nutr ; 59(12): 1379-86, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16118656

RESUMO

OBJECTIVE: The study aimed to characterize the lipid and apolipoprotein profile and the prevalence of cardiovascular risk factors in a population of urban adult women of Morocco. DESIGN: A total of 213 women 25-55 y old were sampled from an agricultural province of Morocco: El Jadida. The following parameters of lipid and apolipoprotein profile were measured: plasma triglycerides (TG), plasma cholesterol (TC), triglyceride-rich lipoprotein triglycerides (TRL-TG), TRL-cholesterol (TRL-C), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), and apolipoproteins A1, B, B48, CIII and E. Waist circumference (WC), body mass index (BMI) and blood pressure (BP) were also determined. RESULTS: The women studied showed the following pattern: elevated TC, LDL-C levels and TC/HDL-C in 10, 19.4 and in 43.8%, respectively; low HDL-C levels in 45.3% (<0.9 mmol/l) or in 95% (when the cutoff <1.3 mmol/l is used), elevated TG levels in 11.8%. Elevated TRL-C (>0.6 mmol/l) and TRL-TG (>0.8 mmol/l) were observed in 13.4%. Obesity and hypertension were highly prevalent in 23.9 and 16.5%, respectively. Plasma triglyceride concentrations were closely correlated with plasma concentrations of TRL-TG (R = 0.86, P = 0.0001), apoB (R = 0.50, P = 0.0001) and apoCIII (R = 0.52, P = 0.0001) and moderately correlated with HDL-C levels (R = -0.3, P = 0.0001) and BMI (R = 0.4, P = 0.0001). The association between BMI and systolic blood pressure was statistically significant (R = 0.3, P = 0.0001). Obesity, BP, TRL-C, TRL-TG, TG, apoB and apoCIII increased with age. CONCLUSION: There is a high prevalence of some risk factors for cardiovascular disease including altered lipid and lipoprotein profiles in the Moroccan urban women studied, some of these risk factors are associated with age.


Assuntos
Envelhecimento/sangue , Doenças Cardiovasculares/epidemiologia , Colesterol/sangue , Triglicerídeos/sangue , Adulto , Apolipoproteínas/sangue , Biomarcadores/sangue , Pressão Sanguínea , Índice de Massa Corporal , Doenças Cardiovasculares/sangue , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Estudos Transversais , Feminino , Humanos , Pessoa de Meia-Idade , Marrocos , Prevalência , Fatores de Risco , População Urbana , Relação Cintura-Quadril
18.
J Clin Endocrinol Metab ; 84(1): 184-91, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9920081

RESUMO

We know that upper body obesity is associated with metabolic complications, but we don't know how regional body fat distribution influences postprandial lipemia in obese adults. Thus, this study explored the respective effects of android or gynoid types of obesity and fasting triglyceridemia on postprandial lipid metabolism and especially triglyceride-rich lipoproteins. Twenty-four obese and 6 lean normotriglyceridemic women (control), age 24-57 yr, were enrolled. Among obese women with an android phenotype, 9 exhibited normal plasma triglyceride levels (mean: 1.38 mmol/L) (NTAO), and 7 displayed a frank hypertriglyceridemia (mean: 2.40 mmol/L) (HTAO). The 8 patients with a gynoid phenotype had normal triglyceride levels (mean: 1.00 mmol/L) (GO). All were given a mixed test meal providing 40 g triglycerides. Serum and incremental chylomicron triglycerides 0-7 h areas under the curve (AUCs) as well as triglyceride levels in apoB-48-containing triglyceride-rich lipoprotein (TRLs) or chylomicrons were significantly higher in HTAOs and NTAOs than in GOs and controls postprandially. The size of chylomicron particles was bigger in controls and GOs than in HTAOs and NTAOs postprandially. Android obese subjects showed abnormally elevated fasting apoB-48 and apoB-100 triglyceride-rich lipoprotein (TRL) levels. Most abnormalities that were found correlated to plasma levels of insulin and apoC-III. In conclusion, an abnormal postprandial lipid pattern is a trait of abdominal obesity even without fasting hypertriglyceridemia.


Assuntos
Tecido Adiposo/metabolismo , Obesidade/sangue , Período Pós-Prandial/fisiologia , Triglicerídeos/sangue , Adulto , Apolipoproteína C-III , Apolipoproteínas C/sangue , Feminino , Humanos , Insulina/sangue , Mucosa Intestinal/metabolismo , Lipase Lipoproteica/sangue , Lipoproteínas/sangue , Fígado/metabolismo , Pessoa de Meia-Idade
19.
Am J Clin Nutr ; 49(6): 1192-202, 1989 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2543204

RESUMO

We investigated the effects of fiber-rich wheat bran and wheat germ on dietary fat and cholesterol assimilation. Rats were given a test meal containing [14C]triolein and [3H]cholesterol. After various digestion periods, addition of the wheat fractions (10% of meal solids) did not modify the lipid gastric emptying rate. Gastric and intestinal triglyceride lipolysis was significantly reduced when wheat fractions were present. The mucosal uptakes of [14C]lipids and [3H]cholesterol were significantly modified by the wheat fractions after 1 and 2.5 h. No shift in the site of intestinal absorption and no change in the distribution of labeled lipid in the intestinal mucosa was observed. Plasma [14C]lipids and [3H]cholesterol were significantly decreased by both wheat fractions whereas these increased cecal accumulation of dietary lipids and cholesterol. Thus wheat bran and wheat germ alter fat and cholesterol processing in rats. A mechanism of action accounting for the data observed in proposed.


Assuntos
Colesterol na Dieta/metabolismo , Gorduras na Dieta/metabolismo , Fibras na Dieta/farmacologia , Digestão , Absorção Intestinal , Animais , Ceco/metabolismo , Mucosa Gástrica/metabolismo , Mucosa Intestinal/metabolismo , Intestino Delgado/metabolismo , Cinética , Lipídeos/sangue , Lipólise , Masculino , Ratos , Ratos Endogâmicos , Triglicerídeos/metabolismo , Trioleína/metabolismo , Triticum
20.
Am J Clin Nutr ; 66(2): 357-65, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9250115

RESUMO

To investigate the mechanisms behind the serum cholesterol-lowering effect of oat fiber, we simultaneously measured postprandial lipid responses, serum lathosterol concentrations, and small bowel excretion of fat and sterols in ileostomy subjects given test meals high or low in oat fiber. Six ileostomy subjects (three women and three men) were served an oat-bran test meal (OB; 16.3 g fiber) and a wheat test meal (6.3 g fiber) in random order. After the postprandial 7-h period, a controlled, low-fat, cholesterol-free diet was served and ileostomy effluent was sampled throughout the 24-h period. Bile acid and fat excretion (24 h) increased by 93% and 146%, respectively (P < 0.05), and total and endogenous cholesterol excretion decreased by 14% and 19%, respectively (P < 0.05), after the OB test meal. The change in hepatic cholesterol synthesis was strongly related to the change in bile acid excretion (Spearman r = 0.89, P < 0.02). The postprandial chylomicron lipid concentration tended to be lower after the OB test meal (-43% for cholesterol, P = 0.07) whereas there was no difference in cholesterol absorption measured by isotope in five subjects. The main effect of the viscous oat beta-glucan seems to be related to increased bile acid excretion and subsequent changes in synthesis and endogenous excretion of cholesterol. An additional effect may have been a delay in the micellar lipid solubilization process and a consequent reduction in the secretion of chylomicrons into the circulation.


Assuntos
Colesterol/metabolismo , Fibras na Dieta/administração & dosagem , Ileostomia , Lipídeos/sangue , Período Pós-Prandial , Adulto , Apolipoproteínas E/genética , Avena , Colesterol/biossíntese , Colesterol/sangue , Gorduras na Dieta/análise , Fezes/química , Feminino , Humanos , Insulina/sangue , Lipase/sangue , Lipídeos/análise , Lipase Lipoproteica/sangue , Fígado/enzimologia , Masculino , Pessoa de Meia-Idade , Fenótipo , Triticum
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