Anemia de las enfermedades crónicas asociada a obesidad: papel de la hepcidina como mediador central / Hepcidin as a central mediator of anemia of chronic diseases associated with obesity

Recent evidence suggests that obesity-related inflammation may play a central role in hepcidin regulation. Hepcidin is a key regulator ofiron homeostasis and has now been suggested as a central mediator ofiron metabolism disorders involved in the pathogenesis of anemia of chronic disease. In this review, we focus on subclinical inflammation in obesity and its effect on hepcidin levels, as the most plausible explanation for the relationship between anemia of chronic disease and obesity.

Interleucina-10 e interferón gamma en adolescentes de sexo femenino anémicas con depósitos de hierro depletados / IL-10 and gamma interferon in anemic female adolescent with depleted body reserves of iron

La anemia es el desorden nutricional de mayor prevalencia en el mundo. Estudios sobre anemia por depleción de hierro (ADFe) y citocinas son escasos en humanos. Objetivo Analizar en adolescentes de sexo femenino con ADFe las concentraciones séricas de IL-10 e IFN-gamma. Métodos: Se estudiaron 56 adolescentes (16,1 +/- 1,1 años). Se consideró anemia a una Hb<120 g/L; depleción de hierro (DFe)=ferritina<12 micrones g/L; riesgo de DFe=12-20 micrones g/L y normal>20 micrones g/L. IL-10 e IFN-gamma fueron determinados en suero por ELISA (pg/mL). Los datos fueron analizados con SAS,p<0,05. Resultados: La prevalencia de anemia fue 39,29 por ciento; DFe 33,93 por ciento; Riesgo de DFe=23,22 por ciento y ferritina normal=42,85 por ciento. Las adolescentes anémicas mostraron incremento del IFN-gamma sérico respecto a las no anémicas (NA) p<0,0001. La correlación de Pearson mostró una relación negativa significativa entre Hemoglobina-IFN-gamma y ferritina sérica-IFN-gamma. Discusión: Anemia, DFe y ADFe asociado con el incremento en los niveles séricos de FN-gamma pudieran deberse a efectos inmunoreguladores de esta citocina en la homeostasis del metabolismo del hierro.

Anemia is the most prevalent nutritional disorders in the world. There are only a few studies on the relationship between anemia and cytokines in humans. Objective: To analyze serum concentration of IL-10 and gamma-IFN in anemic female adolescents with depleted reserves of iron (AFeD). Methods: Fifty-six adolescents (16.1 +/-1.1 years old) were analyzed. Anemia was considered when Hb<120g/L; iron depleted ferritin (FeD) < 12 micron g/L; FeD risk 12-20 micron g/L and normal >20 micron g/l. Cytokines were measured in serum by ELISA (pg/mL). The data was analyzed with the SAS program, p<0.05. Results: The prevalence of anemia was 39.29 percent. FeD=33.93 percent; FeD risk=23.22 percent, and normal serum ferritin=42.85 percent. Anemic adolescents shown increased gamma-IFN serum leveis compared to the non anemic (NA) group. Pearson correlation of Hb with gamma-IFN serum leveis and ferritin with gamma-IFN serum leveis were significant. Discussion: Anemia, FeD and AFeD were associated with high serum leveis of gamma-IFN; this could be due to immunoregulator effects of this cytokine on iron metabolism homeostasis. However, more studies are needed to clarify this relationship.

Modificación de la biodistribución de los glóbulos rojos marcados con 99mtc en la anemia ferropénica / Alteration in the biodistribution of 99mTc-RBC in an animal model of ferropenic anemia

Objetivo: Evaluar la biodistribución de 99mTc-GR en un modelo animal de anemia ferropénica. Materiales y métodos: Se utilizaron ratas alimentadas con dietas con diferente contenido de Fe: grupo A (anemia severa, 6.5 ppm), grupo B (anemia moderada, 18 ppm) y grupo C (control, 100 ppm). Se realizó la marcación in vivo de los 99mTc-GR y se evaluó la EBM y su biodistribución a los 30 minutos y a las 24 horas en sangre, hígado, bazo, tracto gastrointestinal, riñones, corazón y pulmones. Los resultados se expresaron como concentración de actividad porcentual (CA por ciento). Resultados: En todos los grupos la EBM fue superior al 98 por ciento. Se observó un aumento de CA por ciento en bazo a las 24 horas en el grupo A, acompañado de una disminución de la CA por ciento del pool sanguíneo posiblemente por aumento del secuestro esplénico de los GR. En los tres grupos hubo un aumento de la CA por ciento en riñón a las 24 horas. Conclusión: La biodistribución de 99mTc-GR se ve modificada en la anemia ferropénica.

Aim: To evaluate the biodistribution of 99mTc-RBC in an animal model of ferropenic anemia. Materials and methods: We used rats which were fed with different iron contents diets: group A (severeanemia, 6.5 ppm), group B (moderate anemia, 18 ppm) and group C (control, 100 ppm). We performed the in vivo labeling of RBC and evaluated the labeling efficiency and the biodistribution at 30 minutes and 24 hours in blood, liver, spleen, gastrointestinal tract, kidneys, heart and lungs. The results were expressed as activity concentration percentage (CA percent). Results: In all groups the labeling efficiency was higher than 98 percent. We observed an increase of CA percent in spleen at 24 hours in the group A, followed by a decrease of CA percent in blood. This could be a consequence of an increase of splenic uptake of RBC. An increase in CA percent in kidney was obtained at 24 hours for all the groups. Conclusion: An alteration in the RBC biodistribution is observed in an animal model of ferropenic anemia.

Biodisponibilidade do ferro como fator de proteção contra anemia entre crianças de 12 a 16 meses / Iron bioavailability as a protective factor against anemia among children aged 12 to 16 months

OBJETIVO: Este estudo investiga os fatores dietéticos determinantes da ausência de anemia entre lactentes de famílias de baixo nível socioeconômico submetidos a um programa de intervenção nutricional, bem como a adequação do consumo de ferro de acordo com as recomendações. METODOLOGIA: O estudo compreendeu 369 crianças pertencentes a uma coorte do município de São Leopoldo (RS), as quais foram randomizadas ao nascimento para constituírem dois grupos: intervenção e controle. O grupo intervenção foi submetido a orientações dietéticas no primeiro ano de vida, com visitas domiciliares mensais, e o grupo controle foi visitado aos 6 e 12 meses, sem intervenção dietética. Ao final do primeiro ano de vida, realizou-se inquérito alimentar recordatório de 24 horas. O diagnóstico de anemia foi determinado pelo nível de hemoglobina inferior a 11 g/dL. As dietas das crianças foram classificadas de acordo com a biodisponiblidade do ferro presente. RESULTADOS: A prevalência de anemia encontrada neste estudo foi de 63,7 por cento. A proporção de crianças com consumo adequado em relação às recomendações foi estatisticamente mais elevada no grupo sem anemia (26,8 por cento) do que no grupo com anemia (17,7 por cento). As crianças que não apresentaram anemia mostraram maior consumo de ferro (p = 0,019), vitamina C (p = 0,001), densidade energética no jantar (p = 0,006), densidade de ferro por 1.000 calorias (p = 0,045), e 16,3 por cento delas apresentaram dieta com alta biodisponibilidade em ferro (p = 0,002). CONCLUSÕES: A prática alimentar que garante alta biodisponibilidade de ferro protege a criança contra anemia e pode ser usada como proposta de intervenção na rede básica de saúde e no âmbito das secretarias municipais de educação infantil.

OBJECTIVE: This study investigates the nutritional factors that determine the absence of anemia in infants from families with a low socioeconomic background submitted to a nutrition intervention program, as well as iron intake according to recommendations. METHODS: The study included 369 children from a cohort of inhabitants of São Leopoldo, state of Rio Grande do Sul, Brazil, who were randomized at birth into an intervention group and into a control group. The intervention group had nutritional guidance in the first year of life, with monthly follow-up home visits, whereas the control group was visited at 6 and 12 months, without nutritional intervention. At the end of the first year of life, a 24-hour recall was used. Anemia was diagnosed based on a hemoglobin level less than 11 g/dL. The children's diets were classified according to iron bioavailability. RESULTS: The prevalence of anemia amounted to 63.7 percent in this study. The proportion of children with adequate iron intake relative to the recommendations was statistically higher in the nonanemic group (26.8 percent) than in the anemic one (17.7 percent). Nonanemic children had a greater intake of iron (p = 0.019), vitamin C (p = 0.001), energy density at dinner (p = 0.006), iron density per 1,000 calories (p = 0.045); and 16.3 percent of them had a diet with high iron bioavailability (p = 0.002). CONCLUSIONS: A diet with high iron bioavailability protects children from anemia and can be used as an intervention measure by basic health services and by the municipal departments of children's education.

Estado nutricional e absorção intestinal de ferro em crianças com doença hepática crônica com e sem colestase / Nutritional status and intestinal iron absorption in children with chronic hepatic disease with and without cholestasis

OBJETIVO: Avaliar a ingestão alimentar, a ocorrência de desnutrição energético-protéica e de anemia e a absorção intestinal de ferro em crianças com doença hepática crônica. CASUíSTICA E MÉTODOS: Foram estudados 25 pacientes com doença hepática crônica, sendo 15 com colestase e 11 sem colestase. A idade variou entre 6,5 meses e 12,1 anos. A absorção intestinal de ferro foi avaliada pela elevação do ferro sérico uma hora após a ingestão de 1 mg/kg de ferro elementar e pela resposta à ferroterapia oral. A absorção intestinal de ferro foi comparada com um grupo de crianças com anemia ferropriva. RESULTADOS: A ingestão média de energia e proteínas nos pacientes com doença hepática com colestase foi maior do que nos pacientes sem colestase. O déficit nutricional foi mais grave nos pacientes com colestase, predominando os déficits de estatura-idade e peso-idade. A anemia foi freqüente tanto nas crianças com doença hepática com colestase (11/14; 78,6 por cento) como nas sem colestase (7/11; 63,6 por cento). Na doença hepática com colestase, observou-se menor (p < 0,05) absorção intestinal de ferro (90,6±42,1 µg/dl), em comparação com o grupo com anemia ferropriva (159,6±69,9 µg/dl). No entanto, o grupo com colestase apresentou resposta à ferroterapia oral. Os pacientes com doença hepática sem colestase apresentaram absorção intestinal de ferro semelhante à das crianças com anemia ferropriva. CONCLUSÃO: A doença hepática crônica com colestase associa-se com maior comprometimento nutricional. Apesar das crianças com colestase apresentarem evidência de má absorção intestinal de ferro, apresentaram resposta à ferroterapia oral, provavelmente, pela coexistência de deficiência de ferro.

Morphological and functional alterations of the intestine of rats with iron-deficiency anemia

The present study was designed to assess the intestinal absorption of D-xylose and jejunal morphometry in rats with iron-deficiency anemia. Male Wistar rats were randomly divided into a control group (diet containing 50 mg Fe/kg, N = 12) and an anemic group (diet containing <5 mg Fe/kg, N = 12). The animals were housed in individual metabolic cages and deionized water and diet were provided ad libitum for 6 weeks. Hemoglobin and hematocrit were determined at 0, 2, 4, and 6 weeks. At the end of the study the rats were submitted to a D-xylose absorption test (50 mg/100 g body weight) and sacrificed and a jejunal specimen was obtained for morphometric study. At the end of the study the hemoglobin and hematocrit of the anemic rats (8.7 ± 0.9 g/dl and 34.1 ± 2.9 percent, respectively) were significantly (P < 0.05) lower than those of the controls (13.9 ± 1.4 g/dl and 47.1 ± 1.5 percent, respectively). There was no statistical difference in D-xylose absorption between the anemic (46.5 ± 7.4 percent) and control (43.4 ± 9.0 percent) groups. The anemic animals presented statistically greater villus height (445.3 ± 36.8 µm), mucosal thickness (614.3 ± 56.3 µm) and epithelial surface (5063.0 ± 658.6 µm) than control (371.8 ± 34.3, 526.7 ± 62.3 and 4401.2 ± 704.4 µm, respectively; P < 0.05). The increase in jejunum villus height, mucosal thickness and epithelial surface in rats with iron-deficiency anemia suggests a compensatory intestinal mechanism to increase intestinal iron absorption.

Disaccharidase levels in normal epithelium of the small intestine of rats with iron-deficiency anemia

Iron-deficiency anemia is the nutritional deficiency most frequently occurring throughout the world, which manifests as a complex systemic disease involving all cells, affecting enzyme activities and modifying protein synthesis. In view of these considerations, the objective of the present study was to determine the effects of iron-deficiency anemia on disaccharidase and on the epithelial morphokinetics of the jejunal mucosa. Newly weaned male Wistar rats were divided into 4 groups of 10 animals each: C6w received a standard ration containing 36 mg elemental iron per Kg ration for 6 weeks; E6w received and iron-poor ration (5-8 mg/kg ration) for 6 weeks; C10w received an iron-rich ration (36 mg/kg ration) for 10 weeks; E10w received an iron-poor ration for 6 weeks and then an iron-rick ration (36 mg/kg) for an additional 4 weeks. Jejunal fragments were used to measure disaccharidase content and to study cell proliferation. The following results were obtained: 1) a significant reduction (P<0.001) of animal weight, hemoglobin (Hb), serum iron and total iron-binding capacity (TIBC) in groups E6w as compared to C6w; reversal of the alterations in Hb, serum iron and TIBC with iron repletion (E10w = C10w); animal weights continued to be significanly different in group E10w and C10w. 2) Sucrase and maltase levels were unchanged; total and specific lactase levels were significantly lower in group E6w and this reduction was reversed by iron repletion (E10w = C10w). 3) The cell proliferation parameters did not differ between groups. On the basis of these results, we conclude that lactase production was influenced by iron deficiency and that fact was not related to changes in cell population and proliferation in the intestinal mucosa.

Anemia na gestaçäo / Anemia in pregnancy

Os autores pretendem fazer uma breve revisäo bibliográfica, visando a orientaçäo de médicos e estudantes sobre os aspectos fisiológicos e patológicos da anemia na gestaçäo