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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Associação do consumo alimentar com o status de ferro de mulheres saudáveis na idade reprodutiva / Association of food intake with iron status among healthy women at childbearing age

Dias, Gisele Cristina 13 June 2017 (has links)
Uma dieta adequada em ferro biodisponível é fundamental para a prevenção da anemia por deficiência de ferro entre mulheres na idade reprodutiva, que são grupo de alto risco para essa morbidade. Dados da Organização Mundial da Saúde indicam que no Brasil, 19% das mulheres não grávidas em idade reprodutiva são anêmicas. Identificar fatores dietéticos associados com o status de ferro pode nortear políticas atuais voltadas à redução da prevalência de anemia, como é a fortificação de farinhas de trigo e milho com ferro. O objetivo deste estudo foi avaliar a associação entre o consumo habitual de alimentos e o status de ferro de mulheres saudáveis na idade reprodutiva. Foram incluídas 127 mulheres entre estudantes de graduação e de pós-graduação de uma Universidade de São Paulo, com idades entre 18 e 45 anos, saudáveis (relato de menstruação regular e ausência de doenças crônicas ou parasitose intestinal) e não expostas a fatores não dietéticos associados com a deficiência de ferro (gravidez, lactação ou doação de sangue recentes). Foram excluídas do estudo as mulheres com alterações hematológicas ou do status inflamatório e aquelas com dados dietéticos inválidos. A partir de três registros alimentares (RA) e de um questionário de frequência alimentar (QFA), estimou-se o consumo habitual de 30 grupos de alimentos, utilizando a estratégia estatística Multiple Source Method (MSM). Os marcadores do status de ferro utilizados foram ferritina sérica, saturação de transferrina e hemoglobina. Associações foram testadas por análise de regressão linear múltipla, controlando-se pelas covariáveis: ingestão energética habitual, índice de massa corporal, uso de anticoncepcionais hormonais, nível de atividade física, cor de pele autodeclarada, tipo da dieta autodeclarada, idade e escore de fluxo menstrual. As análises foram realizadas no programa SPSS versão 21. Do total de 127 mulheres avaliadas, 16 (12,6%) apresentaram deficiência de ferro (ferritina sérica <15 ng/mL), sendo que 4 delas (3,1%) eram anêmicas (Hb<12g/dL). Valores de ferritina foram positivamente associados com o consumo de \"carnes totais e embutidos\" (&#946; = 0,3%; p = 0,032). Por outro lado, o grupo de \"frutas e sucos naturais\" associou-se negativamente com esse biomarcador (&#946; = - 0,1%; p = 0,039). Uma associação direta entre valores de saturação de transferrina e o consumo de \"carnes bovinas\" foi também encontrada (&#946; = 0,078; p = 0,030). Nenhuma estimativa de consumo habitual de alimentos correlacionou-se com as concentrações circulantes de hemoglobina, ainda que uma forte associação negativa entre esse biomarcador e o relato de restrição dietética de carnes tenha sido observada (&#946; = -0,582; p = 0,006). Entre mulheres adultas saudáveis, estimativas de consumo habitual de carnes e frutas podem predizer variações interindividuais nos biomarcadores do status de ferro. Visando a redução do risco para deficiência de ferro, as recomendações de ingestão desses alimentos devem ser contextualizadas num padrão alimentar saudável e variado, com foco especial na adequação do consumo de carnes não processadas, frutas e sucos naturais. / Dietary adequacy in bioavailable iron is essential to prevent iron deficiency anemia among women at childbearing age, population groups at high-risk for this morbidity. Data from the World Health Organization indicate that, in Brazil, 19% of non-pregnant women at childbearing age are anemic. Identifying dietary factors associated with iron status may guide current policies aimed at lowering the prevalence of anemia, such as the fortification of wheat and corn flours with iron. The aim of this study was to evaluate the association of usual food intake with iron status biomarkers among healthy women at childbearing age. We included 127 students of University of São Paulo aged 18 to 45 years, healthy (self-reporting of regular menstruation and lack of a diagnosed chronic diseases or an intestinal parasitosis) and not exposed to non-dietary factors associated with iron deficiency (recent pregnancy, lactation or blood donation). Cases of hematologic or inflammatory status alterations as well as those with invalid dietary data were excluded from the study. Data from three diet records (DR) and a food frequency questionnaire (FFQ) were used to estimate the usual intake of 30 food groups by employing as the statistical approach the Multiple Source Method (MSM). Biomarkers of iron status were serum ferritin, transferrin saturation index and hemoglobin. Multiple linear regression analysis was used to test associations, with adjustments for the covariates: energy intake, body mass index, hormonal contraceptive use, physical activity level, self-reported skin color, self-reporting of meat dietary restriction, age and a menstrual blood loss score. Analysis were performed in the SPSS program version 21. Among all women, 16 (12.6%) had iron deficiency (serum ferritin < 15 ng/mL), 4 of them (3.1%) were anemic (Hb<12g/dL). In the adjusted models, ferritin values were positively associated with \"total meat and sausages\" intake (&#946; = 0.3%; p = 0.032). On the other hand, \"fruits and natural juices fruits\" intake was negatively associated with this biomarker (&#946; = -0.1%; p = 0.039). A direct association between the transferrin saturation values and \"bovine meat\" intake was also found (&#946; = 0.078; p = 0.030). None of the usual food intake measures was correlated with circulating hemoglobin concentrations, although a strong negative association between this biomarker and self-reporting of meat dietary restriction has been observed (&#946; = - 0.582; p = 0.006). Conclusion: Among adult healthy women, estimates of usual meat and fruit intakes may predict between-person variability of iron status biomarkers. In order to reduce iron deficiency risk, recommendations regarding habitual consumption of these foods must be contextualized in a healthy and varied diet, focusing on the choice of non-processed meats,fruits and natural fruit juice.
32

Ferritin: Mechanistic Studies and Electron Transfer Properties

Zhang, Bo 08 August 2006 (has links)
Ferritins are ubiquitous iron storage proteins in living systems. Although much is known about the iron deposition process in ferritin and a mechanism has been developed, several important issues still remain unknown. One lingering question is the less than stoichiometric quantities of hydrogen peroxide detected in previous studies on animal ferritins. Extensive experimental data on identifying the species in competition for peroxide equivalents point to a surprising conclusion that H2O2 generated in the ferroxidase reaction is consumed by amine buffers that are commonly employed in in vitro ferritin studies, while non-nitrogen containing buffers, such as acetate, phosphate, and carbonate, do not react with H2O2. The effects of amine buffer oxidation on the Fe2+/O2 stoichiometry, the kinetics and the molecular mechanism of iron deposition are discussed. The ~2 nm ferritin shell surrounding the ~4000 Fe(O)OH mineral core was originally thought to isolate the core from the environment. However, synthesized Co- and Mn(O)OH cores in horse spleen and bacteria ferritins are shown to be rapidly reduced by ascorbic acid and horse spleen ferritin containing a reduced Fe(II) core (Fe(II)-HoSF) presumably without direct contact. Further experiments demonstrate that both Fe(II)-HoSF and Co-/Mn-ferritins bind to gold electrodes and exchange electrons through the metallic conductor. These results provide the first direct evidence for electron transfer (ET) through the ferritin shell. The nature of the ET pathway is further investigated by loading iron into native and recombinant ferritins using large oxidants that are too big to enter the ferritin interior and must accept electrons from Fe2+ through this pathway. Experimental results suggest that the endogenous redox center in heteropolymeric animal ferritins and the heme groups in bacteria ferritins mediate ET through the protein shell. Finally, the diffusion properties of ferritin pores are examined toward iron (2+ and 3+) and anion transfer. Iron transfer is studied by the formation of Prussian blue ([FeIIFeIII(CN)6]-) encapsulated in the ferritin cavity, and is consistent with a binding-dissociation model proposed previously for iron transfer through the three-fold channels. When native HoSF is reduced by methyl viologen in saline solutions, small anions such as F-, Cl-, and Br , accumulate in the ferritin interior while phosphate is released. No anion transfer is observed during the reduction of reconstituted HoSF with no phosphate in the core. The possibility of ferritin as an anion pump in vivo is proposed.
33

Detection of <i>in vitro</i> and <i>in vivo</i> oxidative modifications of ferritin and transferrin by mass spectrometry : hereditary hemochromatosis as a model

Ahmed, Mohamed S. 12 December 2007
Hereditary Hemochromatosis (HH) is an inherited recessive autosomal disorder characterized by accumulation of excess iron. When iron binding proteins become saturated, concentrations of free, or non-transferrin-bound iron (NTBI) rise, a condition thought to be responsible for the adverse effects associated with HH. To investigate that disturbing iron homeostasis plays a role in free radical injury in HH, protein carbonyls were found to be 1-7 times higher in patients with HH than in controls, with the greatest increases being observed in untreated HH patients with high ferritin and >90% transferrin saturation with iron. An Unpaired t test revealed a P value of 0.0278 (P< 0.05), which is considered to be statistically significant. Our data showed a significant positive correlation (linear relationship) between the level of carbonyl content and ferritin concentration in plasma samples from patients with HH. In vitro oxidation of transferrin and ferritin standards with hydrogen peroxide and excess iron, followed by immobilized trypsin digestion (Poroszyme), high-resolution LC-MS/MS analysis (Q-TOF Ultima, Waters) and MS/MS data processing (PEAKS, Bioinformatics Solution), identified several tryptic peptides containing oxidized Met,Trp and His residues. Mapping of the oxidized ferritin residues showed them to be located on the inner face of each sub-unit, the face directed toward the ferritin core where iron is normally stored. Using the same methodology, oxidized residues were subsequently detected in ferritin and transferrin isolated from plasma samples of patients severely affected with HH. Comparing of MS/MS spectra of in vitro oxidized samples that have most fragment ion peaks in common with oxidized peptide MS/MS spectra from samples of patients with HH revealed a significant correlation between the two. These data show that elevated NTBI may be involved in oxidative modification of the iron binding proteins, ferritin and transferrin, and that such modifications may play a significant role in the pathophysiology of HH.
34

Iron metabolism in the <i>Drosophila</i> mutants <i>fumble</i> and <i>malvolio</i>

Hanson, Akela Danielle 31 July 2007
The Drosophila mutant fumble has a defect in mitochondrially targeted pantothenate kinase (PANK) and exhibits a movement disorder in the females. The human disease pantothenate kinase associated neurodegeneration (PKAN) has the same genetic defect and a neurodegenerative phenotype as well as iron accumulation in the brain. We have found that fumble females accumulate almost 2 fold more iron in the heads than wildtype. Dietary iron supplementation increases the iron accumulation in the heads further. The small isoform of malvolio (MVL), a homologue of mammalian NRAMP iron transporters, is expressed in the heads of flies. Its expression is upregulated in the fumble females, as well as in dietary iron supplemented wildtype flies. Unlike in the wildtype, dietary iron supplementation leads to a downregulation of MVL in the fumble flies. Although iron levels were elevated in fumble, ferritin expression was relatively unchanged and remained unchanged in the heads of fumble and wildtype with dietary iron supplementation. <p>The Drosophila mutant malvolio was used to determine how iron metabolism is affected when the MVL gene is defective. Iron levels were unchanged in malvolio relative to its parental strain (w1118) with or without dietary iron supplementation. Despite similar iron levels, a small decrease in ferritin expression was found in malvolio relative to w1118, and dietary iron increased ferritin expression in malvolio. However ferritin expression decreased in the parental strain of malvolio after iron supplementation. <p>Most of the iron in the Drosophila heads was in the form of goethite and ferrihydrite. The presence of iron oxides implies that this iron is in a mineralized storage form, likely ferritin. Dietary iron supplementation induced the appearance of ferric phosphates in fumble, malvolio, and wildtype. The subcellular location of this iron is unknown. It may be non-transferrin bound iron in the hemolymph, or a cytosolic intermediate in the labile iron pool. Also of note was the presence of transferrin-bound iron in wildtype heads on normal diet that was not seen after iron supplementation or in the heads of the fumble mutant. The presence in fumble of the kind of ferrihydrite characteristic of the mitochondrial protein frataxin may indicate that iron is accumulating in mitochondria.<p>The upregulation of MVL in the fumble mutant is of significant interest because it is the first protein involved in iron metabolism found to be altered with mitochondrial PANK deficiency. A disruption in MVL could be relevant to the brain iron accumulation in fumble and could be a treatment target for human PKAN.
35

Detection of <i>in vitro</i> and <i>in vivo</i> oxidative modifications of ferritin and transferrin by mass spectrometry : hereditary hemochromatosis as a model

Ahmed, Mohamed S. 12 December 2007 (has links)
Hereditary Hemochromatosis (HH) is an inherited recessive autosomal disorder characterized by accumulation of excess iron. When iron binding proteins become saturated, concentrations of free, or non-transferrin-bound iron (NTBI) rise, a condition thought to be responsible for the adverse effects associated with HH. To investigate that disturbing iron homeostasis plays a role in free radical injury in HH, protein carbonyls were found to be 1-7 times higher in patients with HH than in controls, with the greatest increases being observed in untreated HH patients with high ferritin and >90% transferrin saturation with iron. An Unpaired t test revealed a P value of 0.0278 (P< 0.05), which is considered to be statistically significant. Our data showed a significant positive correlation (linear relationship) between the level of carbonyl content and ferritin concentration in plasma samples from patients with HH. In vitro oxidation of transferrin and ferritin standards with hydrogen peroxide and excess iron, followed by immobilized trypsin digestion (Poroszyme), high-resolution LC-MS/MS analysis (Q-TOF Ultima, Waters) and MS/MS data processing (PEAKS, Bioinformatics Solution), identified several tryptic peptides containing oxidized Met,Trp and His residues. Mapping of the oxidized ferritin residues showed them to be located on the inner face of each sub-unit, the face directed toward the ferritin core where iron is normally stored. Using the same methodology, oxidized residues were subsequently detected in ferritin and transferrin isolated from plasma samples of patients severely affected with HH. Comparing of MS/MS spectra of in vitro oxidized samples that have most fragment ion peaks in common with oxidized peptide MS/MS spectra from samples of patients with HH revealed a significant correlation between the two. These data show that elevated NTBI may be involved in oxidative modification of the iron binding proteins, ferritin and transferrin, and that such modifications may play a significant role in the pathophysiology of HH.
36

Iron metabolism in the <i>Drosophila</i> mutants <i>fumble</i> and <i>malvolio</i>

Hanson, Akela Danielle 31 July 2007 (has links)
The Drosophila mutant fumble has a defect in mitochondrially targeted pantothenate kinase (PANK) and exhibits a movement disorder in the females. The human disease pantothenate kinase associated neurodegeneration (PKAN) has the same genetic defect and a neurodegenerative phenotype as well as iron accumulation in the brain. We have found that fumble females accumulate almost 2 fold more iron in the heads than wildtype. Dietary iron supplementation increases the iron accumulation in the heads further. The small isoform of malvolio (MVL), a homologue of mammalian NRAMP iron transporters, is expressed in the heads of flies. Its expression is upregulated in the fumble females, as well as in dietary iron supplemented wildtype flies. Unlike in the wildtype, dietary iron supplementation leads to a downregulation of MVL in the fumble flies. Although iron levels were elevated in fumble, ferritin expression was relatively unchanged and remained unchanged in the heads of fumble and wildtype with dietary iron supplementation. <p>The Drosophila mutant malvolio was used to determine how iron metabolism is affected when the MVL gene is defective. Iron levels were unchanged in malvolio relative to its parental strain (w1118) with or without dietary iron supplementation. Despite similar iron levels, a small decrease in ferritin expression was found in malvolio relative to w1118, and dietary iron increased ferritin expression in malvolio. However ferritin expression decreased in the parental strain of malvolio after iron supplementation. <p>Most of the iron in the Drosophila heads was in the form of goethite and ferrihydrite. The presence of iron oxides implies that this iron is in a mineralized storage form, likely ferritin. Dietary iron supplementation induced the appearance of ferric phosphates in fumble, malvolio, and wildtype. The subcellular location of this iron is unknown. It may be non-transferrin bound iron in the hemolymph, or a cytosolic intermediate in the labile iron pool. Also of note was the presence of transferrin-bound iron in wildtype heads on normal diet that was not seen after iron supplementation or in the heads of the fumble mutant. The presence in fumble of the kind of ferrihydrite characteristic of the mitochondrial protein frataxin may indicate that iron is accumulating in mitochondria.<p>The upregulation of MVL in the fumble mutant is of significant interest because it is the first protein involved in iron metabolism found to be altered with mitochondrial PANK deficiency. A disruption in MVL could be relevant to the brain iron accumulation in fumble and could be a treatment target for human PKAN.
37

Avaliação molecular e bioquímica do metabolismo do ferro em pacientes portadores de síndrome metabólica

Rauber, Mariana Reis January 2014 (has links)
Introdução: A síndrome metabólica (SM) apresenta elevada prevalência na população mundial, sendo a hiperferritinemia um achado frequente nestes pacientes. A investigação do aumento da ferritina nesta doença representa um desafio diagnóstico, muitas vezes necessitando exames de alto custo, mas sendo fundamental para identificação dos pacientes que apresentam sobrecarga de ferro. Objetivo: Avaliar os parâmetros bioquímicos e moleculares relacionados ao metabolismo do ferro em pacientes portadores de SM. Métodos: Através de um estudo transversal, foram avaliados 94 pacientes portadores de SM de acordo com os critérios da International Diabetes Federation que estavam em acompanhamento no ambulatório de Medicina Interna do HCPA. Foram avaliados dados antropométricos e de diagnóstico para SM, dosagem de ferro, ferritina, a saturação da transferrina, hepcidina, além das mutações C282Y e H63D do gene HFE da hemocromatose. Resultados: A prevalência de hiperferritinemia na população em estudo foi de 27,7%, sendo maior no sexo masculino (53,8%) que no sexo feminino (14,5%) (p<0,001). A elevação da saturação de transferrina, e não da ferritina, se correlacionou com mutações do gene da hemocromatose. A hiperferritinemia se associou com saturação de transferrina (p<0,001) e a hepcidina (p=0,008), após análise de regressão logística. Conclusão: A hiperferritinemia é um achado frequente na SM, sendo mais comum em homens. A dosagem da saturação de transferrina é um bom parâmetro para screening de pacientes com mutação da hemocromatose, como já demonstrado na literatura. Sugere-se a hepcidina como um novo biomarcador com potencial promissor na investigação da hiperferritinemia associada à SM. / Introduction: Metabolic syndrome (MS) has a high prevalence in the world population, and hyperferritinemia is a frequent finding in these patients. The investigation of the increased ferritin in this syndrome represents a diagnostic challenge, often requiring expensive tests, but is essential for identification of patients with iron overload. Objective: To evaluate biochemical and molecular parameters related to iron metabolism in patients with MS. Methods: In a cross-sectional study, we evaluated 94 patients with MS according to the criteria of the International Diabetes Federation who were accompanied in the outpatient clinics of internal medicine, Hospital de Clínicas de Porto Alegre. We evaluated anthropometric data and diagnostic criteria for MS, iron dosage, ferritin, transferrin saturation, hepcidin, besides the C282Y and H63D mutations in the HFE hemochromatosis gene. Results: The prevalence of hyperferritinemia in the study population was 27.7% and was higher in males (53.8%) than in females (14.5%) (p <0.001). The elevation of transferrin saturation, but not ferritin, did relate with mutations the hemochromatosis gene. Hyperferritinemia related to transferrin saturation (p <0.001) and hepcidin (p = 0.008) after logistic regression analysis. Conclusion: Hyperferritinemia is a frequent finding in metabolic syndrome, most frequently in men. Determination of transferrin saturation is a good parameter for screening of patients with hemochromatosis mutation, as already demonstrated in literature. It is suggested hepcidin as a new biomarker with promising potential in research hyperferritinemia associated with MS.
38

Avaliação molecular e bioquímica do metabolismo do ferro em pacientes portadores de síndrome metabólica

Rauber, Mariana Reis January 2014 (has links)
Introdução: A síndrome metabólica (SM) apresenta elevada prevalência na população mundial, sendo a hiperferritinemia um achado frequente nestes pacientes. A investigação do aumento da ferritina nesta doença representa um desafio diagnóstico, muitas vezes necessitando exames de alto custo, mas sendo fundamental para identificação dos pacientes que apresentam sobrecarga de ferro. Objetivo: Avaliar os parâmetros bioquímicos e moleculares relacionados ao metabolismo do ferro em pacientes portadores de SM. Métodos: Através de um estudo transversal, foram avaliados 94 pacientes portadores de SM de acordo com os critérios da International Diabetes Federation que estavam em acompanhamento no ambulatório de Medicina Interna do HCPA. Foram avaliados dados antropométricos e de diagnóstico para SM, dosagem de ferro, ferritina, a saturação da transferrina, hepcidina, além das mutações C282Y e H63D do gene HFE da hemocromatose. Resultados: A prevalência de hiperferritinemia na população em estudo foi de 27,7%, sendo maior no sexo masculino (53,8%) que no sexo feminino (14,5%) (p<0,001). A elevação da saturação de transferrina, e não da ferritina, se correlacionou com mutações do gene da hemocromatose. A hiperferritinemia se associou com saturação de transferrina (p<0,001) e a hepcidina (p=0,008), após análise de regressão logística. Conclusão: A hiperferritinemia é um achado frequente na SM, sendo mais comum em homens. A dosagem da saturação de transferrina é um bom parâmetro para screening de pacientes com mutação da hemocromatose, como já demonstrado na literatura. Sugere-se a hepcidina como um novo biomarcador com potencial promissor na investigação da hiperferritinemia associada à SM. / Introduction: Metabolic syndrome (MS) has a high prevalence in the world population, and hyperferritinemia is a frequent finding in these patients. The investigation of the increased ferritin in this syndrome represents a diagnostic challenge, often requiring expensive tests, but is essential for identification of patients with iron overload. Objective: To evaluate biochemical and molecular parameters related to iron metabolism in patients with MS. Methods: In a cross-sectional study, we evaluated 94 patients with MS according to the criteria of the International Diabetes Federation who were accompanied in the outpatient clinics of internal medicine, Hospital de Clínicas de Porto Alegre. We evaluated anthropometric data and diagnostic criteria for MS, iron dosage, ferritin, transferrin saturation, hepcidin, besides the C282Y and H63D mutations in the HFE hemochromatosis gene. Results: The prevalence of hyperferritinemia in the study population was 27.7% and was higher in males (53.8%) than in females (14.5%) (p <0.001). The elevation of transferrin saturation, but not ferritin, did relate with mutations the hemochromatosis gene. Hyperferritinemia related to transferrin saturation (p <0.001) and hepcidin (p = 0.008) after logistic regression analysis. Conclusion: Hyperferritinemia is a frequent finding in metabolic syndrome, most frequently in men. Determination of transferrin saturation is a good parameter for screening of patients with hemochromatosis mutation, as already demonstrated in literature. It is suggested hepcidin as a new biomarker with promising potential in research hyperferritinemia associated with MS.
39

Iron: essential for life and a source of diseases / Hierro: fundamental para la vida y causante de enfermedades

Gutiérrez, Lucia 25 September 2017 (has links)
El hierro es un elemento fundamental para la vida, siendo imprescindible en procesos vitales como el transporte de oxígeno, la transferencia de electrones, reacciones enzimáticas, metabolismo aeróbico, la fotosíntesis o la fijación de nitrógeno. Dada la relevancia de este elemento en rutas metabólicas centrales para el desarrollo de la vida, no nos tiene que sorprender el gran número de enfermedades que están asociadas a problemas relacionados con el metabolismo del hierro. Las especies patológicas con hierro que aparecen en el marco de algunas enfermedades son materiales nanométricos cuya caracterización presenta grandes dificultades. El conocimiento en detalle de estas especies puede tener gran relevancia en situaciones tan diferentes como la mejora de técnicas de diagnóstico de la malaria o el tratamiento de enfermedades neurodegenerativas. / Iron is a fundamental element for life, being essential in vital processes such as oxygen transport, electron transfer, enzymatic reactions, aerobic metabolism, photosynthesis or nitrogen fixation. Given the relevance of this element in metabolic routes central to life development, it is unsurprising that a great number of pathologies are linked to iron metabolism problems. Iron pathological species that appear in the frame of some diseases are nanometric materials, whose characterization presents huge difficulties. Detailed knowledge of these species may have great relevance in different problems such as the improvement of malaria diagnostic techniques or the treatment of neurodegenerative diseases.
40

Avaliação molecular e bioquímica do metabolismo do ferro em pacientes portadores de síndrome metabólica

Rauber, Mariana Reis January 2014 (has links)
Introdução: A síndrome metabólica (SM) apresenta elevada prevalência na população mundial, sendo a hiperferritinemia um achado frequente nestes pacientes. A investigação do aumento da ferritina nesta doença representa um desafio diagnóstico, muitas vezes necessitando exames de alto custo, mas sendo fundamental para identificação dos pacientes que apresentam sobrecarga de ferro. Objetivo: Avaliar os parâmetros bioquímicos e moleculares relacionados ao metabolismo do ferro em pacientes portadores de SM. Métodos: Através de um estudo transversal, foram avaliados 94 pacientes portadores de SM de acordo com os critérios da International Diabetes Federation que estavam em acompanhamento no ambulatório de Medicina Interna do HCPA. Foram avaliados dados antropométricos e de diagnóstico para SM, dosagem de ferro, ferritina, a saturação da transferrina, hepcidina, além das mutações C282Y e H63D do gene HFE da hemocromatose. Resultados: A prevalência de hiperferritinemia na população em estudo foi de 27,7%, sendo maior no sexo masculino (53,8%) que no sexo feminino (14,5%) (p<0,001). A elevação da saturação de transferrina, e não da ferritina, se correlacionou com mutações do gene da hemocromatose. A hiperferritinemia se associou com saturação de transferrina (p<0,001) e a hepcidina (p=0,008), após análise de regressão logística. Conclusão: A hiperferritinemia é um achado frequente na SM, sendo mais comum em homens. A dosagem da saturação de transferrina é um bom parâmetro para screening de pacientes com mutação da hemocromatose, como já demonstrado na literatura. Sugere-se a hepcidina como um novo biomarcador com potencial promissor na investigação da hiperferritinemia associada à SM. / Introduction: Metabolic syndrome (MS) has a high prevalence in the world population, and hyperferritinemia is a frequent finding in these patients. The investigation of the increased ferritin in this syndrome represents a diagnostic challenge, often requiring expensive tests, but is essential for identification of patients with iron overload. Objective: To evaluate biochemical and molecular parameters related to iron metabolism in patients with MS. Methods: In a cross-sectional study, we evaluated 94 patients with MS according to the criteria of the International Diabetes Federation who were accompanied in the outpatient clinics of internal medicine, Hospital de Clínicas de Porto Alegre. We evaluated anthropometric data and diagnostic criteria for MS, iron dosage, ferritin, transferrin saturation, hepcidin, besides the C282Y and H63D mutations in the HFE hemochromatosis gene. Results: The prevalence of hyperferritinemia in the study population was 27.7% and was higher in males (53.8%) than in females (14.5%) (p <0.001). The elevation of transferrin saturation, but not ferritin, did relate with mutations the hemochromatosis gene. Hyperferritinemia related to transferrin saturation (p <0.001) and hepcidin (p = 0.008) after logistic regression analysis. Conclusion: Hyperferritinemia is a frequent finding in metabolic syndrome, most frequently in men. Determination of transferrin saturation is a good parameter for screening of patients with hemochromatosis mutation, as already demonstrated in literature. It is suggested hepcidin as a new biomarker with promising potential in research hyperferritinemia associated with MS.

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