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1.
J Nutr Biochem ; 79: 108333, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32045724

RESUMO

The maternal protein diet during the perinatal period can program the health of adult offspring. This study in rats evaluated the effects of protein quantity and quality in the maternal diet during gestation and lactation on weight and adiposity in female offspring. Six groups of dams were fed a high-protein (HP; 47% protein) or normal-protein (NP; 19% protein) isocaloric diet during gestation (G) using either cow's milk (M), pea (P) or turkey (T) proteins. During lactation, all dams received the NP diet (protein source unchanged). From postnatal day (PND) 28 until PND70, female pups (n=8) from the dam milk groups were exposed to either an NP milk diet (NPMW) or to dietary self-selection (DSS). All other pups were only exposed to DSS. The DSS design was a choice between five food cups containing HPM, HPP, HPT, carbohydrates or lipids. The weights and food intakes of the animals were recorded throughout the study, and samples from offspring were collected on PND70. During the lactation and postweaning periods, body weight was lower in the pea and turkey groups (NPG and HPG) versus the milk group (P<.0001). DSS groups increased their total energy and fat intakes compared to the NPMW group (P<.0001). In all HPG groups, total adipose tissue was increased (P=.03) associated with higher fasting plasma leptin (P<.05). These results suggest that the maternal protein source impacted offspring body weight and that protein excess during gestation, irrespective of its source, increased the risk of adiposity development in female adult offspring.


Assuntos
Dieta Rica em Proteínas/efeitos adversos , Proteínas Alimentares/administração & dosagem , Fenômenos Fisiológicos da Nutrição Materna , Sobrepeso/metabolismo , Adiposidade/efeitos dos fármacos , Animais , Animais Recém-Nascidos , Peso Corporal/efeitos dos fármacos , Dieta/métodos , Dieta Rica em Proteínas/métodos , Feminino , Lactação , Leptina/sangue , Leite/metabolismo , Sobrepeso/epidemiologia , Gravidez , Efeitos Tardios da Exposição Pré-Natal , Ratos , Ratos Wistar , Fatores de Risco
2.
Nutrients ; 12(2)2020 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-31991777

RESUMO

Fetal and early postnatal nutritional environments contribute to lifelong health. High-protein (HP) intake in early life can increase obesity risk in response to specific feeding conditions after weaning. This study investigated the effects of a maternal HP diet during pregnancy and/or lactation on the metabolic health of offspring. Three groups of dams received a normal-protein (NP, 20E% proteins) diet during gestation and lactation (Control group), an HP diet (55E% proteins) during gestation (HPgest group), or an HP diet during lactation (HPlact group). From weaning until 10 weeks, female pups were exposed to the NP, the HP or the western (W) diet. HPgest pups had more adipocytes (p = 0.009), more subcutaneous adipose tissue (p = 0.04) and increased expression of genes involved in liver fatty acid synthesis at 10 weeks (p < 0.05). HPgest rats also showed higher food intake and adiposity under the W diet compared to the Control and HPlact rats (p ≤ 0.04). The post-weaning HP diet reduced weight (p < 0.0001), food intake (p < 0.0001), adiposity (p < 0.0001) and glucose tolerance (p < 0.0001) compared to the NP and W diets; this effect was enhanced in the HPgest group (p = 0.04). These results show that a maternal HP diet during gestation, but not lactation, leads to a higher susceptibility to obesity and glucose intolerance in female offspring.


Assuntos
Dieta Rica em Proteínas/efeitos adversos , Intolerância à Glucose/etiologia , Obesidade/etiologia , Efeitos Tardios da Exposição Pré-Natal , Fatores Etários , Fenômenos Fisiológicos da Nutrição Animal , Animais , Feminino , Idade Gestacional , Intolerância à Glucose/fisiopatologia , Lactação , Fenômenos Fisiológicos da Nutrição Materna , Obesidade/fisiopatologia , Gravidez , Ratos Wistar , Medição de Risco , Fatores de Risco , Fatores Sexuais
3.
Nutrients ; 11(1)2019 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-30621263

RESUMO

Diet of mothers during gestation may impact offspring phenotype. This study evaluated the consequences of a maternal High-Protein (HP) diet during gestation on food preferences and phenotypic characteristics in adult rat offspring. Dams were fed a HP or a Normal-Protein (NP) isocaloric diet during gestation only. Weaned female pups were divided into 3 diet groups: NP control or one of two dietary self-selection (DSS) conditions. In DSS1, offspring had a free choice between proteins (100%) or a mix of carbohydrates (88%) and lipids (12%). In DSS2, the choice was between proteins (100%), carbohydrate (100%) or lipids (100%). DSS2 groups consumed more of their energy from protein and lipids, with a decreased carbohydrate intake (p < 0.0001) compared to NP groups, regardless of the maternal diet. Offspring from HP gestation dams fed the DSS2 diet (HPDSS2) had a 41.2% increase of total adiposity compared to NPDSS2 (p < 0.03). Liver Insulin receptor and Insulin substrate receptor 1 expression was decreased in offspring from HP compared to NP gestation dams. These results showed the specific effects of DSS and maternal diet and data suggested that adult, female offspring exposed to a maternal HP diet during foetal life were more prone to adiposity development, in response to postweaning food conditions.


Assuntos
Peso Corporal , Dieta Rica em Proteínas , Preferências Alimentares/fisiologia , Insulina/metabolismo , Nutrientes/administração & dosagem , Efeitos Tardios da Exposição Pré-Natal , Adiposidade/fisiologia , Animais , Composição Corporal , Carboidratos da Dieta/administração & dosagem , Gorduras na Dieta/administração & dosagem , Proteínas Alimentares/administração & dosagem , Ingestão de Energia , Feminino , Leptina/sangue , Fígado/metabolismo , Fenômenos Fisiológicos da Nutrição Materna , Gravidez , Ratos , Transdução de Sinais
4.
J Nutr ; 146(1): 21-9, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26674762

RESUMO

BACKGROUND: Early-life nutrition has a programming effect on later metabolic health; however, the impact of exposure to a high-protein (HP) diet is still being investigated. OBJECTIVE: This study evaluated the consequences on pup phenotype of an HP diet during gestation and lactation and after weaning. METHODS: Wistar rat dams were separated into 2 groups fed an HP (55% protein) or normal protein (NP) (control; 20% protein) isocaloric diet during gestation, and each group subsequently was separated into 2 subgroups that were fed an HP or NP diet during lactation. After weaning, male and female pups from each mother subgroup were separated into 2 groups that were fed either an NP or HP diet until they were 6 wk old. Measurements included weight, food intake, body composition, blood glucose, insulin, glucagon, leptin, insulin-like growth factor I, and lipids. RESULTS: Feeding mothers the HP diet during gestation or lactation induced lower postweaning pup weight (gestation diet × time, P < 0.0001; lactation diet × time, P < 0.0001). Regardless of dams' diets, pups receiving HP compared with NP diet after weaning had 7% lower weight (NP, 135.0 ± 2.6 g; HP, 124.4 ± 2.5 g; P < 0.0001), 16% lower total energy intake (NP, 777 ± 14 kcal; HP, 649 ± 13 kcal; P < 0.0001) and 31% lower adiposity (P < 0.0001). Pups receiving HP compared with NP diet after weaning had increased blood glucose, insulin, and glucagon when food deprived (P < 0.0001 for all). The HP compared with the NP diet during gestation induced higher blood glucose in food-deprived rats (NP, 83.2 ± 2.1 mg/dL; HP, 91.2 ± 2.1 mg/dL; P = 0.046) and increased plasma insulin in fed pups receiving the postweaning NP diet (gestation diet × postweaning diet, P = 0.02). CONCLUSION: Increasing the protein concentration of the rat dams' diet during gestation, and to a lesser extent during lactation, and of the pups' diet after weaning influenced pup phenotype, including body weight, fat accumulation, food intake, and glucose tolerance at 6 wk of age.


Assuntos
Glicemia/metabolismo , Proteínas Alimentares/administração & dosagem , Homeostase , Lactação , Fenômenos Fisiológicos da Nutrição Materna , Adiposidade , Animais , Composição Corporal , Peso Corporal , Ingestão de Energia , Feminino , Microbioma Gastrointestinal , Glucagon/sangue , Insulina/sangue , Fator de Crescimento Insulin-Like I/metabolismo , Intestinos/microbiologia , Leptina/sangue , Masculino , Gravidez , Ratos , Ratos Wistar , Triglicerídeos/sangue , Desmame
5.
Am J Physiol Gastrointest Liver Physiol ; 299(5): G1030-7, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20689060

RESUMO

Hyperproteic diets are used in human nutrition to obtain body weight reduction. Although increased protein ingestion results in an increased transfer of proteins from the small to the large intestine, there is little information on the consequences of the use of such diets on the composition of large intestine content and on epithelial cell morphology and metabolism. Rats were fed for 15 days with either a normoproteic (NP, 14% protein) or a hyperproteic isocaloric diet (HP, 53% protein), and absorptive colonocytes were observed by electron microscopy or isolated for enzyme activity studies. The colonic luminal content was recovered for biochemical analysis. Absorbing colonocytes were characterized by a 1.7-fold reduction in the height of the brush-border membranes (P = 0.0001) after HP diet consumption when compared with NP. This coincided in the whole colon content of HP animals with a 1.8-fold higher mass content (P = 0.0020), a 2.2-fold higher water content (P = 0.0240), a 5.2-fold higher protease activity (P = 0.0104), a 5.5-fold higher ammonia content (P = 0.0008), and a more than twofold higher propionate, valerate, isobutyrate, and isovalerate content (P < 0.05). The basal oxygen consumption of colonocytes was similar in the NP and HP groups, but ammonia was found to provoke a dose-dependent decrease of oxygen consumption in the isolated absorbing colonocytes. The activity of glutamine synthetase (which condenses ammonia and glutamate) was found to be much higher in colonocytes than in small intestine enterocytes and was 1.6-fold higher (P = 0.0304) in colonocytes isolated from HP animals than NP. Glutaminase activity remained unchanged. Thus hyperproteic diet ingestion causes marked changes both in the luminal environment of colonocytes and in the characteristics of these cells, demonstrating that hyperproteic diet interferes with colonocyte metabolism and morphology. Possible causal relationships between energy metabolism, reduced height of colonocyte brush-border membranes, and reduced water absorption are discussed.


Assuntos
Forma Celular/efeitos dos fármacos , Colo/efeitos dos fármacos , Proteínas Alimentares/metabolismo , Células Epiteliais/efeitos dos fármacos , Conteúdo Gastrointestinal/efeitos dos fármacos , Amônia/análise , Amônia/farmacologia , Animais , Água Corporal , Colo/metabolismo , Proteínas Alimentares/administração & dosagem , Células Epiteliais/fisiologia , Conteúdo Gastrointestinal/química , Glutamato-Amônia Ligase/metabolismo , Masculino , Consumo de Oxigênio/efeitos dos fármacos , Ratos , Ratos Wistar
6.
J Agric Food Chem ; 55(23): 9719-26, 2007 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-17941690

RESUMO

Roasting is a critical process in coffee production as it enables the development of flavor and aroma. At the same time, roasting may lead to the formation of nondesirable compounds, such as polycyclic aromatic hydrocarbons (PAHs). In this study, Arabica green coffee beans from Cuba were roasted under controlled conditions to monitor PAH formation during the roasting process. Roasting was performed in a pilot spouted bed roaster, with the inlet air temperature varying from 180 to 260 degrees C, using both dark (20 min) and light (5 min) roasting conditions. Several PAHs were determined in both roasted coffee samples and green coffee samples. Also, coffee brews, obtained using an electric coffee maker, were analyzed for final estimation of PAH transfer coefficients to the infusion. Formation of phenanthrene, anthracene, and benzo[a]anthracene in coffee beans was observed at temperatures above 220 degrees C, whereas formation of pyrene and chrysene required 260 degrees C. Low levels of benzo[g,h,i]perylene were also noted for dark roasting under 260 degrees C, with simultaneous partial degradation of three-cycle PAHs, suggesting that transformation of low molecular PAHs to high molecular PAHs occurs as the roasting degree is increased. The PAH transfer to the infusion was quite moderate (<35%), with a slightly lower extractability for dark-roasted coffee as compared to light-roasted coffee.


Assuntos
Coffea/química , Café/química , Manipulação de Alimentos/métodos , Temperatura Alta , Hidrocarbonetos Policíclicos Aromáticos/análise , Sementes/química
7.
J Agric Food Chem ; 54(20): 7413-21, 2006 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-17002402

RESUMO

Sample treatment procedures were tested for the determination of polycyclic aromatic hydrocarbons (PAHs) in ground coffee. Pressurized liquid extraction (PLE), under different conditions, was combined with several cleanup methods, namely in situ purification, C18-silica solid-phase extraction (SPE), silica SPE, acid digestion, and alkaline saponification. Soxhlet extraction and direct alkaline saponification were also tested. Best results were obtained using PLE with hexane/acetone 50:50 (v/v) under 150 degrees C. Alkaline saponification followed by cyclohexane extraction and silica SPE was required to eliminate interferent compounds. Finally, 11 PAHs could be quantified in ground coffee with limits of detection in the range of 0.11-0.18 microg kg(-1). Application to ground Arabica coffee lots from Colombia revealed the presence of several PAHs, giving an overall toxicity equivalence in the range of 0.16-0.87 microg kg(-1). PAH identification was performed using both high-performance liquid chromatography-diode array detection and gas chromatography coupled to mass spectrometry.


Assuntos
Café/química , Hidrocarbonetos Policíclicos Aromáticos/análise , Sementes/química , Cromatografia Líquida de Alta Pressão , Cicloexanos , Cromatografia Gasosa-Espectrometria de Massas , Concentração de Íons de Hidrogênio , Controle de Qualidade
8.
Chemosphere ; 59(10): 1427-37, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15876386

RESUMO

The use of the Fenton's reagent process has been investigated for the remediation of environmental matrices contaminated by polycyclic aromatic hydrocarbons (PAHs). Laboratory experiments were first conducted in aqueous solutions, to study the kinetics of oxidation and adsorption of PAHs. Benzo[a]pyrene was more rapidly degraded than adsorbed, while only partial oxidation of fluoranthene occurred. In the case of benzo[b]fluoranthene, its adsorption prevented its oxidation. Besides competition effects between PAHs were found, with slower oxidation of mixtures as compared to single PAH solutions. Apparition of some by-products was observed, and a di-hydroxylated derivative of benzo[a]pyrene could be identified under our conditions. Consequently, application to solid environmental matrices (soil, sludge and sediment samples) was performed using large amounts of reagents. The efficiency of the Fenton treatment was dependent on the matrix characteristics (such as its organic carbon content) and the PAH availability (correlated to the date and level of contamination). However, no pH adjustment was required, as well as no iron addition due to the presence of iron oxides in the solid matrices, suggesting the potential application of Fenton-like treatment for the remediation of PAH-contaminated environmental solids.


Assuntos
Sedimentos Geológicos/análise , Hidrocarbonetos Policíclicos Aromáticos/química , Esgotos/análise , Poluentes do Solo/análise , Solo/análise , Adsorção , Cromatografia Líquida de Alta Pressão , Poluentes Ambientais/análise , Peróxido de Hidrogênio , Concentração de Íons de Hidrogênio , Indicadores e Reagentes , Ferro , Cinética , Oxirredução , Hidrocarbonetos Policíclicos Aromáticos/isolamento & purificação , Espectrofotometria Ultravioleta
9.
J Agric Food Chem ; 53(4): 871-9, 2005 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-15712991

RESUMO

The presence of polycyclic aromatic hydrocarbons (PAHs) in coffee has been reported and is suspected to be due to the degradation of coffee compounds during the roasting step. Due to the high toxicity of these compounds, among which benzo[a]pyrene is known to be the most carcinogenic, their presence in the coffee, especially the coffee brew that is directly ingested by the consumer, is of prime importance. However, due to the low solubility of these compounds, their concentrations are expected to be rather low. As a consequence, reliable and sensitive analytical methods are required. The aim of this study was to develop a reliable and fast analytical procedure to determine these organic micropollutants in coffee brew samples. PAHs were retained on a 0.5 g polystyrene-divinylbenzene cartridge before being eluted by a mixture of methanol/tetrahydrofuran (10:90 v/v), concentrated, and directly analyzed by reversed-phase high-performance liquid chromatography coupled to a fluorescence detector. Application to the determination of PAHs in several coffee brew samples is also given, with mean estimated concentrations in the range of 0-100 ng L(-1) for suspected benzo[b]fluoranthene and benzo[a]pyrene, whereas no fluoranthene could be detected. Tentative identification was made on the basis of UV spectra. However, identification of the suspected traces of PAHs could not be achieved due to matrix effects, so that the presence of coeluting compounds may not be excluded.


Assuntos
Café/química , Hidrocarbonetos Policíclicos Aromáticos/análise , Cromatografia Líquida de Alta Pressão/métodos , Poliestirenos , Solventes , Compostos de Vinila
10.
J Chromatogr A ; 999(1-2): 175-84, 2003 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-12885062

RESUMO

The presence of toxic organic micropollutants in municipal sewage sludges is a major problem on account of risks associated with the agricultural use of the sludges and therefore maximum tolerance limits are imposed. The aim of our study was to develop a reliable and fast analytical procedure for the determination of polycyclic aromatic hydrocarbons in sewage sludges, using focused microwave-assisted extraction. Optimization of the extraction conditions was performed on real matrices. The results of a 2(3) factorial design showed that extraction time was the only influential factor. The selected conditions (30 W, 10 min, 30 ml solvent) were used for real sludges and a certified marine sediment, leading to recoveries of between 56 and 75%. Results of an interlaboratory test confirmed these values. Finally, the technique was compared to traditional techniques (Soxhlet, sonication), and the more recent pressurized liquid extraction technique. Focused microwave-assisted extraction remains an attractive alternative technique due to its rapidity, the low solvent volume required and its moderate investment cost.


Assuntos
Micro-Ondas , Compostos Policíclicos/análise , Esgotos/química , Solventes/química , Cromatografia Líquida de Alta Pressão/métodos , Reprodutibilidade dos Testes , Espectrometria de Fluorescência/métodos
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