RESUMO
Zinc homeostasis is achieved after intake variation by changes in the expression levels of zinc transporters. The aim of this study was to evaluate dietary intake (by 24-h recall), absorption, plasma zinc (by absorption spectrophotometry) and the expression levels (by quantitative PCR), of the transporters ZIP1 (zinc importer) and ZnT1 (zinc exporter) in peripheral white blood cells from 24 adolescent girls before and after drinking zinc-fortified milk for 27 day. Zinc intake increased (p < 0.001) from 10.5 ± 3.9 mg/day to 17.6 ± 4.4 mg/day, and its estimated absorption from 3.1 ± 1.2 to 5.3 ± 1.3 mg/day. Mean plasma zinc concentration remained unchanged (p > 0.05) near 150 µg/dL, but increased by 31 µg/dL (p < 0.05) for 6/24 adolescents (group A) and decreased by 25 µg/dL (p < 0.05) for other 6/24 adolescents (group B). Expression of ZIP1 in blood leukocytes was reduced 1.4-fold (p < 0.006) in group A, while for the expression of ZnT1 there was no difference after intervention (p = 0.39). An increase of dietary zinc after 27-days consumption of fortified-milk did not increase (p > 0.05) the plasma level of adolescent girls but for 6/24 participants from group A in spite of the formerly appropriation, which cellular zinc uptake decreased as assessed by reduction of the expression of ZIP1.
Assuntos
Proteínas de Transporte de Cátions/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Zinco/administração & dosagem , Adolescente , Animais , Proteínas de Transporte de Cátions/genética , Criança , Feminino , Alimentos Fortificados , Homeostase , Humanos , Leite/química , Zinco/sangueRESUMO
Celiac disease (CD) is an autoimmune-mediated enteropathy triggered by dietary gluten in genetically prone individuals. The current treatment for CD is a strict lifelong gluten-free diet. However, in some CD patients following a strict gluten-free diet, the symptoms do not remit. These cases may be refractory CD or due to gluten contamination; however, the lack of response could be related to other dietary ingredients, such as maize, which is one of the most common alternatives to wheat used in the gluten-free diet. In some CD patients, as a rare event, peptides from maize prolamins could induce a celiac-like immune response by similar or alternative pathogenic mechanisms to those used by wheat gluten peptides. This is supported by several shared features between wheat and maize prolamins and by some experimental results. Given that gluten peptides induce an immune response of the intestinal mucosa both in vivo and in vitro, peptides from maize prolamins could also be tested to determine whether they also induce a cellular immune response. Hypothetically, maize prolamins could be harmful for a very limited subgroup of CD patients, especially those that are non-responsive, and if it is confirmed, they should follow, in addition to a gluten-free, a maize-free diet.
Assuntos
Doença Celíaca/diagnóstico , Doença Celíaca/imunologia , Imunidade Celular/efeitos dos fármacos , Prolaminas/imunologia , Zea mays/química , Doença Celíaca/dietoterapia , Dieta Livre de Glúten , Glutens/efeitos adversos , Glutens/imunologia , Humanos , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/imunologia , Prolaminas/efeitos adversos , Triticum/efeitos adversos , Triticum/químicaRESUMO
The risk assessment of genetically modified (GM) crops for human nutrition and health has not been systematic. Evaluations for each GM crop or trait have been conducted using different feeding periods, animal models, and parameters. The most common result is that GM and conventional sources induce similar nutritional performance and growth in animals. However, adverse microscopic and molecular effects of some GM foods in different organs or tissues have been reported. Diversity among the methods and results of the risk assessments reflects the complexity of the subject. While there are currently no standardized methods to evaluate the safety of GM foods, attempts towards harmonization are on the way. More scientific effort is necessary in order to build confidence in the evaluation and acceptance of GM foods.
Assuntos
Alimentos Geneticamente Modificados/efeitos adversos , Saúde , Valor Nutritivo , Plantas Geneticamente Modificadas/efeitos adversos , Animais , Comportamento do Consumidor , Qualidade de Produtos para o Consumidor , Resistência a Medicamentos/genética , Glicina/análogos & derivados , Humanos , Oryza/genética , Medição de Risco , Solanum tuberosum/genética , Glycine max/genética , Zea mays/genética , GlifosatoRESUMO
Structural and physicochemical characteristics of mesquite gum (from Prosopis velutina) were investigated using FT-IR spectroscopic, mass spectrometric and chromatographic methods. Four fractions (F-I, F-IIa, F-IIb and F-III) were isolated by hydrophobic interaction chromatography. The samples were characterized and analyzed for their monosaccharide and oligomers composition by high performance anion-exchange chromatography with pulsed amperometric detection (HPAEC-PAD). L-Arabinose (L-Ara) and D-galactose (D-Gal) were found as the main carbohydrate constituent residues in the polysaccharides from mesquite gum and their ratio (L-Ara/D-Gal) varied within the range 2.54 to 3.06 among the various fractions. Small amounts of D-glucose (D-Glc), D-mannose (D-Man) and D-xylose (D-Xyl) were also detected, particularly in Fractions IIa, IIb and III. Infrared spectroscopy identified polysaccharides and protein in all the samples. Data from mass spectrometry (MALDI-TOF MS) was consistent with the idea that the structure corresponding to the periphereal chains of Fraction I is predominantly a chain of pentoses attached to uronic acid.
Assuntos
Hexoses/análise , Gomas Vegetais/análise , Prosopis/química , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas/métodos , Espectroscopia de Infravermelho com Transformada de Fourier/métodosRESUMO
Mice fed genetically modified (GM) soybean were not affected in nutritional performance, but pancreatic microscopic features were disturbed. The mechanisms for these contradictory findings are unknown. This study analysed the histology of acinar pancreatic cells and the expression of pancreatitis-associated protein (PAP) and trypsinogen mRNA in rats fed GM soy protein. Two bioassays were run, each one with 34 Wistar rats distributed into two groups fed with non-GM or GM-soy protein (18% protein) for 0, 1, 3, 5, 15 and 30 days. Nutritional evaluation, plasma amylase levels, pancreatic histological analysis and quantification of PAP and trypsinogen mRNAs levels using quantitative real-time RT-PCR were done. No differences in nutritional performance among rats fed non-GM and GM diets were found. The GM, but not the non-GM, diet induced zymogen-granule depletion after 15 days feeding, returning to normal levels after 30 days (P < 0.05). Acinar disorganization started as early as 5 days after initiation of the GM diet and it recovered after 30 days. Levels of PAP mRNA significantly increased in the GM diet between day 1 and day 3 and decreased to the basal level by day 15. Trypsinogen mRNA peaked at two different times; at day 1 and at day 15, decreasing to basal levels after 30 days. Plasma amylase levels remained unchanged at all times. This indicates that GM soy protein intake affected pancreas function, evidenced by the early acute PAP mRNA increased levels and pancreas cellular changes followed by recuperation of acinar cells after 30 days.
Assuntos
Glycine max/genética , Pâncreas/patologia , Plantas Geneticamente Modificadas/metabolismo , Amilases/sangue , Fenômenos Fisiológicos da Nutrição Animal , Animais , Antígenos de Neoplasias/genética , Antígenos de Neoplasias/metabolismo , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Lectinas Tipo C/genética , Lectinas Tipo C/metabolismo , Masculino , Pâncreas/enzimologia , Pâncreas/metabolismo , Proteínas Associadas a Pancreatite , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Fatores de Tempo , Tripsinogênio/genética , Tripsinogênio/metabolismoRESUMO
OBJECTIVE: To evaluate the energy, nutrient intakes and dietary patterns of Mexican lactating women at one month postpartum, and the associations of maternal age and region on their intakes. METHODS: A total of 60 women were studied: 41 from Northwest and 19 from Central Mexico, 33 adolescent and 27 adult women. Data were collected through two quantitative 24 h recalls. Two more recalls were used in a sub sample to calculate the coefficient of variation of intakes. Menus were based on the consumption frequency of foods. RESULTS: The mean energy intake of the adolescent women (2354 +/- 1199 kcal) and those of Central Mexico (1690 +/- 981 kcal) was lower than the recommendations. Zinc, calcium, vitamin E, C and folate were inadequate (55 to 85% prevalence of inadequacy). Energy, dietary fiber, sodium, potassium, iron and folate intakes were higher (P < 0.05) in Northwest Mexico. Northwestern women consumed less variety of vegetables or fruits compared to Mexico City region women. Wheat tortillas and beans were from Northwestern but not from the Mexico City region diet. CONCLUSIONS: The energy and nutrient intakes of women were different by regional hospital and not by age. Education about the importance of the maternal diet during lactation should be directed toward increasing consumption of foods rich in micronutrients.