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1.
Br J Nutr ; 123(10): 1094-1108, 2020 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-32172712

RESUMO

The present study reports the effects of a high-fat (HF) diet of over 8 weeks on the Fe status of growing rats. Tissue Fe levels were analysed by atomic absorption spectrophotometry, and whole-body adiposity was measured by dual-energy X-ray absorptiometry. Histopathology and morphometry of adipose tissue were performed. Liver homogenates were used for measuring ferroportin-1 protein levels by immunoblotting, and transcript levels were used for Fe genes measured by real-time PCR. Tissue Fe pools were fit to a compartmental biokinetic model in which Fe was assessed using fourteen compartments and twenty-seven transfer constants (kj,i from tissue 'i' to tissue 'j') adapted from the International Commission on Radiological Protection (ICRP) 69. Ten kj,i were calculated from the experimental data using non-linear regression, and seventeen were estimated by allometry according to the formula ${k_{i,j}} = a \times {M^b}$. Validation of the model was carried out by comparing predicted and analysed Fe pool sizes in erythrocytes, the liver and the spleen. Body adiposity was negatively associated with serum Fe levels and positively associated with liver Fe stores. An inferred increase in Fe transfer from bone marrow to the liver paralleled higher hepatic Fe concentrations and ferritin heavy-chain mRNA levels in the HF diet-fed animals, suggesting that liver Fe accumulation occurred at least in part due to a favoured liver erythrocyte uptake. If this feeding condition was to be prolonged, impaired Fe decompartmentalisation may occur, ultimately resulting in dysmetabolic Fe overload.


Assuntos
Adiposidade , Dieta Hiperlipídica/efeitos adversos , Sobrecarga de Ferro/etiologia , Ferro/metabolismo , Absorciometria de Fóton , Animais , Proteínas de Transporte de Cátions/análise , Modelos Animais de Doenças , Fígado/metabolismo , Ratos , Baço/metabolismo
2.
Food Chem ; 285: 171-179, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-30797332

RESUMO

The effect of moderate Fe overload in the diet and its interaction with phytate, and/or yacon flour (YF), recognized as an inhibitor, and facilitator, of Fe absorption, respectively, was evaluated in healthy rats. For this purpose the following parameters were analyzed: (1) apparent iron (Fe), copper (Cu) and zinc (Zn) absorption; (2) blood Fe; (3) blood lipids (cholesterol, tryacylglicerol); (4) blood AST and ALT; (5) liver histology (histopathology, hemosiderin depots, apoptosis index; (6) liver fatty acid incorporation; (7) liver antioxidant enzyme activity. Moderate Fe overload may cause change in some liver markers (hemosiderin depots, apoptosis index and GPx) and blood lipids (total cholesterol and VLDL) and the interaction with yacon flour, and phytate, in the Fe overloaded diets may exert a protective effect on these alterations.


Assuntos
Dieta , Farinha/análise , Ferro/química , Fígado/enzimologia , Ácido Fítico/química , Adsorção , Alanina Transaminase/sangue , Animais , Antioxidantes/metabolismo , Apoptose , Aspartato Aminotransferases/sangue , Colesterol/sangue , Cobre/química , Ácidos Graxos/metabolismo , Hepatócitos/citologia , Hepatócitos/metabolismo , Ferro/sangue , Fígado/metabolismo , Fígado/patologia , Masculino , Ratos , Ratos Wistar , Triglicerídeos/sangue , Zinco/química
3.
Nutrients ; 10(5)2018 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-29883384

RESUMO

Predictive iron bioavailability (FeBio) methods aimed at evaluating the association between diet and body iron have been proposed, but few studies explored their validity and practical usefulness in epidemiological studies. In this cross-sectional study involving 127 women (18⁻42 years) with presumably steady-state body iron balance, correlations were checked among various FeBio estimates (probabilistic approach and meal-based and diet-based algorithms) and serum ferritin (SF) concentrations. Iron deficiency was defined as SF < 15 µg/L. Pearson correlation, Friedman test, and linear regression were employed. Iron intake and prevalence of iron deficiency were 10.9 mg/day and 12.6%. Algorithm estimates were strongly correlated (0.69≤ r ≥0.85; p < 0.001), although diet-based models (8.5⁻8.9%) diverged from meal-based models (11.6⁻12.8%; p < 0.001). Still, all algorithms underestimated the probabilistic approach (17.2%). No significant association was found between SF and FeBio from Monsen (1978), Reddy (2000), and Armah (2013) algorithms. Nevertheless, there was a 30⁻37% difference in SF concentrations between women stratified at extreme tertiles of FeBio from Hallberg and Hulthén (2000) and Collings’ (2013) models. The results demonstrate discordance of FeBio from probabilistic approach and algorithm methods while suggesting two models with best performances to rank individuals according to their bioavailable iron intakes.


Assuntos
Anemia Ferropriva/sangue , Ferritinas/sangue , Aptidão Genética , Ferro da Dieta/sangue , Modelos Biológicos , Adolescente , Adulto , Algoritmos , Anemia Ferropriva/diagnóstico , Anemia Ferropriva/epidemiologia , Disponibilidade Biológica , Biomarcadores/sangue , Brasil/epidemiologia , Estudos Transversais , Feminino , Humanos , Ferro da Dieta/administração & dosagem , Idade Materna , Valor Preditivo dos Testes , Prevalência , Probabilidade , Reprodutibilidade dos Testes , Adulto Jovem
4.
Nutr Res ; 53: 32-39, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29685625

RESUMO

The role of hepcidin in iron homeostasis in preeclamptic pregnant women is unclear. To test the hypothesis that increased serum iron in women diagnosed with preeclampsia results from decreased production of hepcidin, we performed an observational case-control study in which serum hepcidin concentration, dietary iron intake, hematological indices, iron status, liver function, and inflammatory markers in 18 preeclamptic women and 18 healthy normotensive pregnant women of similar age range were evaluated. Iron intake was established via a food frequency questionnaire, whereas hematological indices, iron status, liver function, and inflammatory markers were assessed using standard protocols. Hematocrit was significantly higher (P = .031) in the preeclamptic group compared with the control, whereas erythropoietin level was significantly lower (P = .003). The pronounced inflammatory status of preeclamptic women was confirmed by significantly higher concentrations of interleukin-6 (P = .001), tumor necrosis factor-α (P < .001), and ferritin (P < .001). Nonetheless, the preeclamptic group exhibited significantly higher serum iron (P = .012) and transferrin saturation (P = .006), and these alterations were accompanied by lower hepcidin levels (P = .047). No significant correlations between hepcidin concentration and iron status parameters were observed in either group. However, a positive and significant correlation between hepcidin concentration and C-reactive protein was observed in the preeclamptic group (r = 0.474; P = .047). We conclude that high serum iron in preeclamptic women is likely caused by low production of hepcidin, thus supporting the hypothesis originally stated.


Assuntos
Proteína C-Reativa/metabolismo , Hepcidinas/sangue , Inflamação/etiologia , Sobrecarga de Ferro/etiologia , Ferro da Dieta/sangue , Ferro/sangue , Pré-Eclâmpsia/sangue , Adolescente , Adulto , Estudos de Casos e Controles , Inquéritos sobre Dietas , Eritropoetina/sangue , Feminino , Ferritinas/sangue , Hematócrito , Homeostase , Humanos , Inflamação/sangue , Interleucina-6/sangue , Sobrecarga de Ferro/sangue , Estado Nutricional , Gravidez , Transferrina/metabolismo , Fator de Necrose Tumoral alfa/sangue , Adulto Jovem
5.
J Nutr Biochem ; 55: 200-208, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29554498

RESUMO

Magnesium (Mg2+) is a mineral with the ability to influence cell proliferation and to modulate inflammatory/immune responses, due to its anti-inflammatory properties. In addition, mesenchymal stem cells (MSCs) modulate the function of all major immune cell populations. Knowing that, the current work aimed to investigate the effects of Mg2+ enrichment, and its influence on the immunomodulatory capacity of MSCs. Murine C3H/10T1/2 MSCs were cultivated in media with different concentrations of Mg2+ (0, 1, 3 and 5 mM), in order to evaluate the effects of Mg2+ on MSC immunomodulatory properties, cell proliferation rates, expression of NFκB and STAT-3, production of IL-1ß, IL-6, TGF-ß, IL-10, PGE2 and NO, and TRPM7 expression. The results showed that TRPM7 is expressed in MSCs, but Mg2+, in the way that cells were cultivated, did not affect TRPM7 expression. Additionally, there was no difference in the intracellular concentration of Mg2+. Mg2+, especially at 5 mM, raised proliferation rates of MSCs, and modulated immune responses by decreasing levels of IL-1ß and IL-6, and by increasing levels of IL-10 and PGE2 in cells stimulated with LPS or TNF-α. In addition, MSCs cultured in 5 mM Mg2+ expressed lower levels of pNFκB/NFκB and higher levels of pSTAT-3/STAT-3. Furthermore, conditioned media from MSCs reduced lymphocyte and macrophage proliferation, but Mg2+ did not affect this parameter. In addition, conditioned media from MSCs cultured at 5 mM of Mg2+ modulated the production profile of cytokines, especially of IL-1ß and IL-6 in macrophages. In conclusion, Mg2+ is able to modulate some immunoregulatory properties of MSCs.


Assuntos
Citocinas/metabolismo , Magnésio/fisiologia , Células-Tronco Mesenquimais/imunologia , Animais , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Meios de Cultivo Condicionados/farmacologia , Citocinas/imunologia , Dinoprostona/metabolismo , Imunomodulação , Linfócitos/citologia , Linfócitos/efeitos dos fármacos , Macrófagos/citologia , Macrófagos/metabolismo , Magnésio/farmacologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Camundongos , NF-kappa B/metabolismo , Óxido Nítrico/metabolismo , Fator de Transcrição STAT3/metabolismo , Canais de Cátion TRPM/metabolismo
6.
Artigo em Inglês | LILACS | ID: biblio-881214

RESUMO

Magnesium (Mg), an essential ion for the human body, is involved in various enzymatic reactions, particularly those related to energy transfer, storage, and transport. Longitudinal studies show that hypomagnesaemia (Mg serum concentration <0.75 mmol/L) and Mg dietary inadequacy (daily intake < EAR (Estimated Average Requirement) for age/gender) are conditions related to metabolic disorders of the immune and cardiovascular system and often occur in obese and diabetic individuals. Poor eating habits, reduced Mg content in food and water are the main causes of the decrease in Mg intake by the general population. In clinical practice, the serum concentration of this mineral is the most widely used marker for diagnosing deficiency. However, the serum concentration does not reflect the nutritional Mg status since it can be maintained by mobilization of body storage, mainly the bone. Thus, the use of serum concentration as the only routine biomarker of Mg status may hinder the diagnosis of Mg deficiency. In clinical and experimental research, different methods for Mg status assessment are proposed (plasma, erythrocyte, urine), but they are seldom used in clinical routine. In some countries (such as USA and Brazil) the average daily Mg dietary ingestion of more than 60% of the adult population is lower than the Estimated Average Requirement for age and gender, and these data are not too different for individuals with chronic non-communicable diseases. It is unclear whether it is an actual reduction of Mg consumption or if the recommendations are overestimated. If we assume that the recommendations are correct, the question is if this condition constitutes a risk factor for chronic diseases or the hypomagnesemia described in some diseases is a consequence of physiopathological changes. This review has the latest information of human and animal studies about Mg status evaluated from plasma, erythrocyte and urine, dietary inadequacy, and its relation to inflammation and to components of metabolic syndrome.


Assuntos
Humanos , Masculino , Feminino , Magnésio/análise , Magnésio/metabolismo , Magnésio/uso terapêutico , Doença Crônica/prevenção & controle , Resistência à Insulina
7.
Nutrire Rev. Soc. Bras. Aliment. Nutr ; 41: 1-10, Dec. 2016. tab
Artigo em Inglês | LILACS | ID: biblio-880415

RESUMO

BACKGROUND: Improvements in the iron status of a population as result of food fortification are expected at the long term. In Brazil, the effectiveness of mandatory flour fortification with iron has been evidenced mostly from surveys on gestational anemia after 1 or 2 years from its implementation, in 2004. Our aim was to assess hemoglobin (Hb) concentrations and the prevalences of anemia and linked erythrocyte morphology patterns among pregnant women in 2006 and 2008.METHODS: The study design was retrospective and cross-sectional. The analysis was based on secondary data in 546medical records from women at the times of their first prenatal attendance in 13 public primary healthcare units of the Butantan Administrative Region from São Paulo (SP), Brazil. Anemia was evaluated from Hb concentration (cut-off <11.0 g/dL) and erythrocyte morphology patterns from mean corpuscular volume (MCV), mean corpuscular Hb concentration (MHC), and red cell distribution widths (RDW). Recorded sociodemographic and obstetric data included maternal age, gestational age, ethnoracial self-classification, and residence type. Student's t tests, analysis of variance, Chi-squared tests, and multiple linear and logistic regressions were employed in the statistical analysis using a significance level of 5 %.RESULTS:The prevalence of anemia was 9.7 % in 2006 and 9.4 % in 2008 (P= 0.922), with no significant difference in mean Hb concentrations (P= 0.159). Normocytosis (normal MVC), normochromia (normal MHC), and anisocytosis (high RDW) were found in most anemia cases, suggesting that the low Hb concentrations resulted from mixed causes. In multiple regression analysis, gestational age at the first prenatal attendance was an independent predictor of low Hb and of having anemia. Moreover, black ethnoracial self-classification was associated with lower Hb. CONCLUSIONS: The prevalence of gestational anemia was low among women in both of the studied periods, representing a mild public health problem. Our results highlight the importance of early prenatal care as a means of reducing gestation-associated risks. The erythrocyte morphology pattern found in most cases of low Hb levels suggests that, besides iron deficiency, hemoglobin pathies and nutritional deficiencies of folate and vitamin B12 are common complicating factors of gestational anemia in our setting.


Assuntos
Humanos , Feminino , Gravidez , Anemia Ferropriva/prevenção & controle , Eritrócitos/metabolismo , Eritrócitos/fisiologia , Cuidado Pré-Natal , Atenção Primária à Saúde
8.
Clin Nutr ; 34(6): 1166-71, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25559945

RESUMO

BACKGROUND & AIMS: Preeclampsia is responsible for more than one-third of all maternal deaths in Brazil. The objectives of the present study were to evaluate magnesium status and its association with oxidative stress and inflammation in preeclamptic women, and to identify the predictor variables of the disorder. METHODS: The study population consisted of 36 women divided into preeclamptic (n = 18) and control groups (n = 18). The preeclamptic group included women (≥20 weeks of pregnancy) with arterial pressure ≥ 140/90 mmHg and proteinuria >0.3 g/24 h, while the control group comprised pregnant women with no clinical/obstetric complications. Magnesium intake was assessed via a food frequency questionnaire validated for pregnant women in Brazil. Plasma, erythrocyte and urinary magnesium levels were determined by flame atomic absorption spectroscopy, while oxidative stress and inflammatory markers were assessed using standard protocols. Logistic regression analysis was used to identify the predictors of preeclampsia. RESULTS: Preeclamptic and control groups were similar with respect to magnesium intake and urinary excretion, while plasma and erythrocyte magnesium concentrations were higher in the former group. Plasma magnesium was positively correlated with catalase and glutathione peroxidase activities and with concentrations of interleukin-6 and tumor necrosis factor alpha. Regression analysis showed that plasma magnesium and urinary 8-isoprostane were associated with preeclampsia. CONCLUSION: Magnesium status appears to result from homeostatic imbalance and physiological alterations typical of preeclampsia. Increased plasma magnesium and decreased urinary 8-isoprostane were considered predictors of preeclampsia.


Assuntos
Inflamação/sangue , Magnésio/sangue , Estresse Oxidativo , Pré-Eclâmpsia/sangue , Adolescente , Adulto , Biomarcadores/sangue , Biomarcadores/urina , Índice de Massa Corporal , Peso Corporal , Brasil , Estudos de Casos e Controles , Catalase/sangue , Dinoprosta/análogos & derivados , Dinoprosta/urina , Feminino , Glutationa Peroxidase/sangue , Humanos , Interleucina-6/sangue , Modelos Logísticos , Pré-Eclâmpsia/diagnóstico , Gravidez , Fator de Necrose Tumoral alfa/sangue , Adulto Jovem
9.
Br J Nutr ; 112(8): 1286-95, 2014 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-25192308

RESUMO

The present study investigated the effects of fructo-oligosaccharides (FOS) on the bioavailability of Fe from ferric pyrophosphate (FP), a water-insoluble compound, in Fe-deficient anaemic rats that were subjected to a Hb repletion assay. Male Wistar rats (n 64) were fed adequate or low (8 mg/kg) Fe diets for 15 d followed by 1 or 2 weeks of Fe repletion with diets providing 35 mg Fe/kg as ferrous sulphate (FS), FP or FP that was mixed with 7·5% FOS in the form of yacon flour or Raftilose P95 (RAF), a purified source of FOS. The effects of FOS were observed within the 1st week of the repletion period. Fe bioavailability was improved by FOS supplementation, as measured by Hb regeneration efficiency and hepatic Fe stores, which were more pronounced in the RAF group. Moreover, RAF supplementation resulted in a higher biological value relative to that of the FP group. FOS supplementation resulted in caecal enlargement, in addition to acidification and Fe species redistribution in the caecal contents relative to the control rats. These effects occurred concomitantly with decreased ferroportin (FPN)-1 expression in the caecal mucosa, which was similar in magnitude to that observed in the FS group. Caecum mucosal morphometry was influenced by FOS supplementation, whereas crypt fission and cell proliferation were highest in the caecum of the RAF group. These results reinforce the effects of FOS as Fe bioavailability enhancers in anaemic rats that are sustained by early changes in their caecal environment (decreased mucosal FPN-1 expression and increased Fe absorbability, crypt fission and cellularity).


Assuntos
Anemia Ferropriva/dietoterapia , Proteínas de Transporte de Cátions/metabolismo , Ceco/patologia , Mucosa Intestinal/patologia , Ferro da Dieta/administração & dosagem , Ferro/análise , Oligossacarídeos/uso terapêutico , Anemia Ferropriva/sangue , Anemia Ferropriva/metabolismo , Anemia Ferropriva/patologia , Animais , Brasil , Proteínas de Transporte de Cátions/genética , Ceco/metabolismo , Proliferação de Células , Difosfatos/administração & dosagem , Compostos Ferrosos/administração & dosagem , Alimentos Fortificados , Frutose/análise , Conteúdo Gastrointestinal/química , Hemoglobinas/análise , Ferro/administração & dosagem , Ferro/sangue , Ferro/química , Ferro/metabolismo , Ferro da Dieta/metabolismo , Ferro da Dieta/uso terapêutico , Masculino , Valor Nutritivo , Oligossacarídeos/química , Raízes de Plantas/química , Prebióticos , Ratos Wistar , Traqueófitas/química
10.
Nutr Hosp ; 30(3): 570-6, 2014 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-25238833

RESUMO

INTRODUCTION: Studies have shown that oxidative stress, found in patients with type 2 diabetes, may be due to changes in the metabolism of minerals, such as magnesium and iron. Data related to compartmentalization of these minerals in diabetes are scarce and controversial. OBJECTIVE: This study assessed the influence of magnesium on biochemical parameters of iron and oxidative stress in patients with type 2 diabetes. METHODS: A case-control study in male and female subjects aged 27-59 years, divided into two groups: type 2 diabetes (n=40) and control (n=48). Intake of magnesium and iron was assessed by three-day food record. Plasma, erythrocyte and urinary levels of magnesium, serum iron, ferritin, total iron binding capacity, fasting glucose, glycated hemoglobin, insulin, creatinine clearance and plasma thiobarbituric acid reactive substances (TBARS) were analyzed. RESULTS AND DISCUSSION: Magnesium intake and plasma magnesium were lower in diabetic subjects. There was low urinary magnesium excretion, with no difference between groups. Although normal, the diabetic group had lower serum iron and ferritin concentrations compared to control subjects. Plasma TBARS in diabetic patients was higher than control while creatinine clearance was lower. An inverse correlation between erythrocyte magnesium and serum iron and ferritin was observed in the diabetes group. CONCLUSIONS: Diabetes induced hypomagnesemia and this, associated with chronic hyperglycemia, may have enhanced oxidative stress. Erythrocyte magnesium may have contributed to prevent iron overload and worsening of oxidative stress and hyperglycemic status.


Introducción: Los estudios han demostrado que el estrés oxidativo, que se encuentra en pacientes con diabetes tipo 2, puede ser debido a cambios en el metabolismo de los minerales, como el magnesio y el hierro. Los datos relacionados con la compartimentación de estos minerales en la diabetes son pocos y cuestionables. Objetivos: Evaluar la influencia del magnesio sobre parámetros bioquímicos de hierro y el estrés oxidativo en pacientes con diabetes tipo 2. Métodos: Estudio caso-control en los sujetos masculinos y femeninos de edad 27 a 59 años, divididos en dos grupos: la diabetes tipo 2 (n = 40) y control (n = 48). La ingesta de magnesio y hierro se evaluó por tres días registro de alimentos. Plasma, eritrocitos y los niveles urinarios de magnesio, hierro sérico, ferritina, capacidad total de fijación del hierro, glucosa en ayunas, hemoglobina glucosilada, la insulina, el aclaramiento de creatinina y el plasma se analizaron tiobarbitúrico sustancias reactivas al ácido (TBARS). Resultados y Discusión: La ingesta de magnesio y el magnesio en plasma fueron más bajos en los pacientes diabéticos. Hubo baja excreción urinaria de magnesio, sin diferencias entre los grupos. Aunque lo normal, el grupo de diabéticos tenían concentraciones de hierro y ferritina sérica inferiores en comparación con los sujetos control. TBARS plasmáticos en los pacientes diabéticos fue mayor que en el control, mientras que la depuración de creatinina fue menor. Se observó una correlación inversa entre el magnesio y el hierro en suero de los eritrocitos y la ferritina en el grupo de diabetes. Conclusiones: Diabetes hipomagnesemia inducida y esto, asociado a la hiperglucemia crónica, pueden haber mejorado el estrés oxidativo. Magnesio eritrocitaria puede haber contribuido a evitar la sobrecarga de hierro y el empeoramiento de estrés oxidativo y el estado de hiperglucemia.


Assuntos
Diabetes Mellitus Tipo 2/metabolismo , Ferro/metabolismo , Magnésio/metabolismo , Estresse Oxidativo , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
11.
Rev. Inst. Adolfo Lutz (Online) ; 73(1): 67-76, jan.-mar. 2014. tab
Artigo em Inglês | LILACS, Sec. Est. Saúde SP | ID: lil-782587

RESUMO

Iron deficiency anemia (IDA) is a widespread nutritional disorder that affects a significant proportion of the Brazilian population. The obligatory fortification of wheat flour with iron and folic acid represents a strategy of the Brazilian Ministry of Health for combating IDA. However, several studies have reported the occurrence of iron in excessive concentrations and insufficient contents of folic acid in commercial flour samples. In the light of these information, a participatory observational study on the wheat flour production processes was undertaken in 11 major flour mills located in the São Paulo state, Brazil. This study aimed at writing a detailed good manufacturing practice (GMP) guidelines for the industrial sectors, including directives for standardized operational procedures (SOPs) on the flour fortification. The outcomes of this study are a GMP checklist and the recommended SOPs, which help to standardize the production processes in flour fortification, which currently is incongruous one, and also to facilitate the work of the government health inspectors...


Assuntos
Humanos , Alimentos Fortificados , Boas Práticas de Fabricação , Padrão de Identidade e Qualidade para Produtos e Serviços , Triticum , Deficiências de Ferro
12.
Clin Nutr ; 33(5): 879-88, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24182515

RESUMO

BACKGROUND & AIMS: To determine if magnesium deficiency aggravates the effects of a high-fat diet in growing rats in terms of obesity, lipid profile and insulin resistance. METHODS: The study population comprised 48 newly weaned male Wistar Hannover rats distributed into four groups according to diet, namely, control group (CT; n = 8), control diet provided ad libitum; pair-feeding control group (PF; n = 16), control diet but in the same controlled amount as animals that received high-fat diets; high-fat diet group (HF; n = 12), and magnesium-deficient high-fat diet group (HFMg(-); n = 12). The parameters investigated were adiposity index, lipid profile, magnesium status, insulin sensitivity and the phosphorylation of proteins involved in the insulin-signaling pathway, i.e. insulin receptor ß-subunit, insulin receptor substrate 1 and protein kinase B. RESULTS: The HF and HFMg(-) groups were similar regarding gain in body mass, adiposity index and lipid profile, but were significantly different from the PF group. The HFMg(-) group exhibited alterations in magnesium homeostasis as revealed by the reduction in urinary and bone concentrations of the mineral. No inter-group differences were observed regarding glucose homeostasis. Protein phosphorylation in the insulin-signaling pathway was significantly reduced in the high-fat groups compared with the control groups, demonstrating that the intake of fat-rich diets increased insulin resistance, a syndrome that was aggravated by magnesium deficiency. CONCLUSIONS: Under the experimental conditions tested, the intake of a magnesium-deficient high-fat diet led to alterations in the insulin-signaling pathway and, consequently, increased insulin resistance.


Assuntos
Adiposidade , Dieta Hiperlipídica/efeitos adversos , Resistência à Insulina , Lipídeos/sangue , Deficiência de Magnésio/sangue , Animais , Composição Corporal , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Jejum , Insulina/sangue , Proteínas Substratos do Receptor de Insulina/genética , Proteínas Substratos do Receptor de Insulina/metabolismo , Magnésio/administração & dosagem , Masculino , Estado Nutricional , Obesidade/sangue , Fosforilação , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Ratos Wistar , Transdução de Sinais , Triglicerídeos/sangue , Desmame
13.
J Nutr Sci Vitaminol (Tokyo) ; 60(6): 397-402, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25866302

RESUMO

In animal models, Fe overload is associated with organ oxidative stress and tissue injury. In this context, luminal Fe may affect the mucosal barrier and function or generate a pathological milieu in the intestine that triggers epithelial cell stress. Here, we hypothesized that increased liver Fe levels resulting from dietary Fe overload may be associated with architectural changes in the cecal mucosa. Weanling male Wistar rats (n=7-10/group) were fed diets (modified from AIN-93G) containing adequate or supplemental Fe (approximately 10 times the recommended levels) for 4 and 12 wk. At euthanasia, the blood Hb was determined, and Fe analyses were performed in stool and liver samples using atomic absorption spectrophotometry. Cecal tissue was collected for histological and morphometric analysis. No significant differences were observed in the blood Hb or Hb Fe pool between groups in either period. Iron overload led to a higher fecal Fe excretion, whereas the liver Fe was increased only after 12 wk when compared with controls. After 4 wk, the consumption of Fe-overloaded diets resulted in changes in the mucosal architecture of the cecum, which were intensified after 12 wk. At this time, these changes were significantly correlated with the hepatic Fe content. These findings suggest that changes in the cecal mucosa may have occurred as a result of oxidative stress caused by excessive amounts of Fe in the intestinal lumen. The consequences of these effects on the intestinal absorption and its implications for liver Fe homeostasis should be considered in future studies.


Assuntos
Ceco/efeitos dos fármacos , Sobrecarga de Ferro/sangue , Ferro da Dieta/administração & dosagem , Ferro da Dieta/sangue , Animais , Ceco/metabolismo , Hemoglobinas/metabolismo , Absorção Intestinal/efeitos dos fármacos , Sobrecarga de Ferro/patologia , Ferro da Dieta/farmacocinética , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Wistar , Fatores de Tempo
14.
Rev. Inst. Adolfo Lutz ; 71(4): 685-690, out.-dez. 2012. tab, graf
Artigo em Português | LILACS, Sec. Est. Saúde SP, SESSP-CTDPROD, Sec. Est. Saúde SP, SESSP-ACVSES, SESSP-IALPROD, Sec. Est. Saúde SP, SESSP-IALACERVO | ID: lil-706159

RESUMO

Neste estudo foi validada a metodologia de análise de magnésio urinário, plasmático e eritrocitário por espectrofotometria de absorção atômica com chama. As análises foram realizadas em pools de amostras de urina, de plasma e de eritrócitos de humanos. Para a validação, foram considerados os parâmetros de linearidade da curva-padrão, faixa de trabalho, limite de detecção (LD), limite de quantificação (LQ), precisão e exatidão da medição. Os LD e LQ da curva foram, respectivamente, de 0,006 e 0,021 μg/mLde Mg para urina e plasma, e de 0,003 e 0,010 μg/mL de Mg para eritrócitos. A faixa linear de trabalho para determinação de Mg foi entre 0,05 e 0,5 μg/mL de Mg, e as curvas-padrão apresentaram coeficientes de correlação maiores do que 0,99, que demonstram a linearidade da metodologia. As precisões intra e interensaio superiores a 90 por cento foram consideradas adequadas. As recuperações obtidas, usando-se materiais de referência certificados, foram de 101 por cento e de 97 por cento, respectivamente, em urina e plasma. As médias de recuperação por adição de padrão foram de 87 por cento para urina e eritrócitos e de 91 por cento para plasma. A metodologia avaliada foi linear, sensível, seletiva, precisa e exata; portanto, são confiáveis os resultados obtidos.


Assuntos
Humanos , Masculino , Feminino , Eritrócitos , Espectrofotometria Atômica , Fluxo Plasmático Renal , Magnésio , Urina
15.
Nutr Res ; 32(7): 542-6, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22901563

RESUMO

Deficiencies in calcium (Ca) and magnesium (Mg) are associated with various complications during pregnancy. To test the hypothesis that the status of these minerals is inadequate in pregnancy, a cross-sectional study was conducted of the dietary intake and status of Ca and Mg in pregnant women (n = 50) attending a general public university hospital in Brazil. Dietary intake was assessed from 4-day food records; levels of plasma Mg, erythrocyte Mg, and urinary Ca and Mg excretion were determined by flame atomic absorption spectroscopy; and type I collagen C-telopeptides were evaluated by enzyme-linked immunosorbent assay. Probabilities of inadequate Ca and Mg intake were exhibited by 58 and 98% of the study population, respectively. The mean levels of urinary Ca and Mg excretion were 8.55 and 3.77 mmol/L, respectively. Plasma C-telopeptides, plasma Mg, and erythrocyte Mg were within normal levels. Multiple linear regression analysis revealed positive relationships among urinary Ca excretion, Ca intake (P = .002) and urinary Mg excretion (P < .001) and between erythrocyte Mg and Mg intake (P = .023). It is concluded that the Ca and Mg status of participants was adequate even though the intake of Ca and Mg was lower than the recommended level.


Assuntos
Cálcio/sangue , Deficiência de Magnésio/fisiopatologia , Magnésio/sangue , Desnutrição/fisiopatologia , Complicações na Gravidez/fisiopatologia , Adulto , Brasil/epidemiologia , Cálcio/deficiência , Cálcio/urina , Colágeno Tipo I/sangue , Estudos Transversais , Ingestão de Energia , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Modelos Lineares , Magnésio/urina , Deficiência de Magnésio/epidemiologia , Desnutrição/complicações , Desnutrição/epidemiologia , Estado Nutricional , Peptídeos/sangue , Gravidez , Complicações na Gravidez/epidemiologia , Adulto Jovem
16.
Rev Saude Publica ; 45(6): 1027-35, 2011 Dec.
Artigo em Inglês, Português | MEDLINE | ID: mdl-22127652

RESUMO

OBJECTIVE: To compare prevalence of anemia and hemoglobin (Hb) levels in Brazilian pregnant women before and after flour fortification with iron. METHODS: A repeated cross-sectional panel study of public health care centers of municipalities in the five Brazilian regions was conducted. Retrospective data were obtained from 12,119 medical records of pregnant women distributed in two groups: before fortification (delivery prior to June 2004) and after fortification (date of last period after June 2005). Anemia was defined as Hb<11.0 g/dl. Hb levels according to gestational age were assessed using two references from the literature. Statistical analysis was carried out using chi-squared tests, Student's t tests, and logistic regression, with a significance level of 5%. RESULTS: In the total sample, prevalence of anemia fell from 25% to 20% after fortification (p<0.001). However, important regional differences were evident: while significant reductions were seen in the Northeast (37% to 29%) and North (32% to 25%) regions, where pre-fortification prevalence was high, smaller reductions were seen in the Southeast (18% to 15%) and South (7% to 6%) regions, where prevalence was low. Hb levels according to gestational age were slightly higher in the first months of pregnancy and lower after the third or fourth months, depending on the reference used. Logistic regression analysis showed that group, geographic region, marital status, trimester of pregnancy, initial nutritional status, and prior pregnancy were associated with anemia (p<0.05). CONCLUSIONS: Prevalence of anemia decreased after fortification, but remains high in the North and Northeast regions. Although fortification may have played a role in this favorable outcome, the contribution of other public policies implemented during the studied period should also be considered.


Assuntos
Anemia Ferropriva/dietoterapia , Alimentos Fortificados/análise , Hemoglobina A/análise , Ferro da Dieta/administração & dosagem , Complicações Hematológicas na Gravidez/epidemiologia , Anemia Ferropriva/epidemiologia , Anemia Ferropriva/prevenção & controle , Brasil/epidemiologia , Atenção à Saúde , Demografia/estatística & dados numéricos , Métodos Epidemiológicos , Feminino , Farinha , Idade Gestacional , Humanos , Gravidez , Complicações Hematológicas na Gravidez/dietoterapia , Cuidado Pré-Natal
17.
Rev. saúde pública ; 45(6): 1027-1035, dez. 2011. tab
Artigo em Português | LILACS | ID: lil-606860

RESUMO

OBJETIVO: Comparar prevalência de anemia e valores de hemoglobina (Hb) em gestantes brasileiras, antes e após a fortificação das farinhas com ferro. MÉTODOS: Estudo de avaliação de painéis repetidos, desenvolvido em serviços públicos de saúde de municípios das cinco regiões brasileiras. Dados retrospectivos foram obtidos de 12.119 prontuários de gestantes distribuídas em dois grupos: antes da fortificação, com parto anterior a junho de 2004, e após a fortificação, com última menstruação após junho de 2005. Anemia foi definida como Hb < 11,0 g/dL. Valores de Hb/idade gestacional foram avaliados segundo dois referenciais da literatura. Foram utilizados teste qui-quadrado, t de Student e regressão logística, com nível de 5 por cento de significância. RESULTADOS: Na amostra total, anemia caiu de 25 por cento para 20 por cento após fortificação (p < 0,001), com médias de Hb significativamente maiores no grupo "após" (p < 0,001). Observaram-se, entretanto, diferenças regionais importantes: reduções significativas nas regiões Nordeste (37 por cento para 29 por cento) e Norte (32 por cento para 25 por cento), onde as prevalências de anemia eram elevadas antes da fortificação, e reduções menores nas regiões Sudeste (18 por cento para 15 por cento) e Sul (7 por cento para 6 por cento), onde as prevalências eram baixas. Os níveis de Hb/idade gestacional de ambos os grupos se mostraram discretamente mais elevados nos primeiros meses, porém bem mais baixos após o terceiro ou quarto mês, dependendo da referência utilizada para comparação. Análise de regressão logística mostrou que grupo, região geográfica, situação conjugal, trimestre gestacional, estado nutricional inicial e gestação anterior associaram-se com anemia (p < 0,05). CONCLUSÕES: A prevalência de anemia diminuiu após a fortificação, porém continua elevada nas regiões Nordeste e Norte. Embora a fortificação possa ter tido papel nesse resultado favorável, há que se considerar a contribuição de outras políticas públicas implementadas no período estudado.


OBJECTIVE: To compare prevalence of anemia and hemoglobin (Hb) levels in Brazilian pregnant women before and after flour fortification with iron. METHODS: A repeated cross-sectional panel study of public health care centers of municipalities in the five Brazilian regions was conducted. Retrospective data were obtained from 12,119 medical records of pregnant women distributed in two groups: before fortification (delivery prior to June 2004) and after fortification (date of last period after June 2005). Anemia was defined as Hb<11.0 g/dl. Hb levels according to gestational age were assessed using two references from the literature. Statistical analysis was carried out using chi-squared tests, Student's t tests, and logistic regression, with a significance level of 5 percent. RESULTS: In the total sample, prevalence of anemia fell from 25 percent to 20 percent after fortification (p<0.001). However, important regional differences were evident: while significant reductions were seen in the Northeast (37 percent to 29 percent) and North (32 percent to 25 percent) regions, where pre-fortification prevalence was high, smaller reductions were seen in the Southeast (18 percent to 15 percent) and South (7 percent to 6 percent) regions, where prevalence was low. Hb levels according to gestational age were slightly higher in the first months of pregnancy and lower after the third or fourth months, depending on the reference used. Logistic regression analysis showed that group, geographic region, marital status, trimester of pregnancy, initial nutritional status, and prior pregnancy were associated with anemia (p<0.05). CONCLUSIONS: Prevalence of anemia decreased after fortification, but remains high in the North and Northeast regions. Although fortification may have played a role in this favorable outcome, the contribution of other public policies implemented during the studied period should also be considered.


OBJETIVO: Comparar prevalencia de anemia y valores de hemoglobina (Hb) en gestantes brasileñas, antes y después de la fortificación de las harinas con hierro. MÉTODOS: Estudio de evaluación de paneles repetidos, desarrollado en servicios públicos de salud de municipios de las cinco regiones brasileñas. Datos retrospectivos se obtuvieron de 12.119 prontuarios de gestantes distribuidas en dos grupos: antes de la fortificación, con parto anterior a junio de 2004, y posterior a la fortificación, con última menstruación después de junio 2005. Anemia fue definida como Hb<11,0 g/dL. Valores de Hb/edad gestacional fueron evaluados según dos referenciales de la literatura. Se utilizaron prueba de chi-cuadrado, t de Student y regresión logística, con nivel de 5 por ciento de significancia. RESULTADOS: En la muestra total, anemia disminuyó de 25 por ciento a 20 por ciento después de la fortificación (p<0,001), con promedios de Hb significativamente mayores en el grupo "posterior" (p<0,001). Se observaron, sin embargo, diferencias regionales importantes: reducciones significativas en las regiones Noreste (de 37 por ciento a 29 por ciento) y Norte (de 32 por ciento a 25 por ciento), donde las prevalencias de anemia eran elevadas antes de la fortificación; y reducciones menores en las regiones Sureste (de 18 por ciento a 15 por ciento) y Sur (de 7 por ciento a 6 por ciento), donde las prevalencias eran bajas. Los niveles de Hb/edad gestacional de ambos grupos se mostraron discretamente mas elevados en los primeros meses, aunque mucho mas bajos posterior al tercero o cuarto mes, dependiendo de la referencia utilizada para comparación. Análisis de regresión logística mostró cual grupo, región geográfica, situación conyugal, trimestre gestacional, estado nutricional inicial y gestación anterior se asociaron con anemia (p<0,05). CONCLUSIONES: La prevalencia de anemia disminuyó posterior a la fortificación, aunque continua elevada en las regiones Noreste y Norte. A pesar de que la fortificación pueda haber tenido papel en este resultado favorable, hay que considerar la contribución de otras políticas públicas implementadas en el periodo estudiado.


Assuntos
Feminino , Humanos , Gravidez , Anemia Ferropriva/dietoterapia , Alimentos Fortificados/análise , Hemoglobina A/análise , Ferro da Dieta/administração & dosagem , Complicações Hematológicas na Gravidez/epidemiologia , Anemia Ferropriva/epidemiologia , Anemia Ferropriva/prevenção & controle , Brasil/epidemiologia , Atenção à Saúde , Demografia/estatística & dados numéricos , Métodos Epidemiológicos , Farinha , Idade Gestacional , Complicações Hematológicas na Gravidez/dietoterapia , Cuidado Pré-Natal
18.
Rev. nutr ; 24(2): 333-344, mar.-abr. 2011.
Artigo em Espanhol | LILACS | ID: lil-593988

RESUMO

En la búsqueda de medidas de prevención de enfermedades crónicas no trasmisibles, se piensa en los prebióticos como una forma efectiva, saludable y relativamente barata para la optimización de la absorción de Ca. El aumento de la expectativa de vida de la población y el incremento de enfermedades como la osteoporosis traen graves consecuencias a la salud del individuo, acarreando importantes desembolsos económicos. En esta revisión se condensa el conocimiento presente sobre el efecto fisiológico del consumo de carbohidratos prebióticos y su posible interferencia en la biodisponibilidad del Ca, como también las posibilidades de su empleo en estrategias para combatir las deficiencias del mineral. Se elaboró una recopilación de los estudios originales realizados con mayor impacto en el tema, dando preferencia a los publicados en los últimos 6 años. Utilizamos las bases de datos PubMed, Lilacs e SciELO, usando las palabras claves calcio, prebióticos e probióticos.


The increased life expectancy and prevalence of non-communicable chronic diseases have serious health and economic consequences on the population. Among the useful tools for preventing osteoporosis, prebiotics are thought to be an effective, healthy and relatively cheap way of optimizing calcium absorption. The objective of this review was to summarize the present knowledge on the physiological effects of prebiotic carbohydrate consumption and its possible interference with calcium bioavailability. The possibility of using prebiotics to fight calcium deficiency was also assessed. The keywords calcium, prebiotics and probiotics were used to search the PubMed, Lilacs and SciELO databases for the most significant original studies on the subject published in the last 6 years.


Assuntos
Cálcio da Dieta/farmacocinética , Disponibilidade Biológica , Prebióticos/análise
19.
20.
Nutr Res ; 29(12): 873-81, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19963161

RESUMO

Feeding mineral-deficient diets enhances absorptive efficiency as an attempt of the body to compensate for the lack of an essential nutrient. Under certain circumstances, it does not succeed; and nutritional deficiency is produced. Our hypothesis was that inulin-type fructans (ITF), which are known to affect mineral absorption, could increase Ca and Fe bioavailability in Ca- and Fe-deficient rats. Male Wistar rats (n = 48, 4 weeks old) were assigned to 1 of 8 groups derived from 2 x 2 x 2 factorial design with 2 levels of added Fe (0 and 35 mg/kg), Ca (0 and 5 g/kg), and ITF (0 and 100 g/kg) for 33 days. The Fe status (hemoglobin, serum Fe, total Fe-binding capacity, transferrin saturation, liver minerals) was evaluated. Tibia minerals (Ca, Mg, and Zn), bone strength, and histomorphometry were determined. In nondeficient rats, ITF supplementation did not affect Fe status or organ minerals, with the exception of tibia Mg. Moreover, ITF improved bone resilience and led to a reduction in eroded surface per body surface and number of osteoclasts per area. In Ca-deficient rats, ITF increased liver (Fe and Zn) and tibia (Zn) mineral levels but impaired tibia Mg, yield load, and resilience. In conclusion, ITF worsened the tibia Mg levels and elastic properties when supplemented in Ca-deficient diets. In contrast, although bone Ca was not affected in nondeficient rats under the present experimental conditions, bone quality improved, as demonstrated by a moderate reduction in femur osteoclast resorption and significant increases in tibia Mg content and elasticity.


Assuntos
Conservadores da Densidade Óssea/administração & dosagem , Densidade Óssea , Osso e Ossos/fisiologia , Cálcio/deficiência , Dieta , Frutanos/administração & dosagem , Deficiências de Ferro , Animais , Biomarcadores/análise , Biomarcadores/sangue , Fenômenos Biomecânicos , Peso Corporal , Osso e Ossos/química , Osso e Ossos/citologia , Cálcio/análise , Ceco/patologia , Inulina , Ferro/análise , Fígado/química , Fígado/patologia , Magnésio/análise , Masculino , Estado Nutricional , Tamanho do Órgão , Ratos , Ratos Wistar
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