M. Olivares

Zinc inhibits nonheme iron bioavailability in humans

There is increasing concern about potential negative interactions in combined iron and zinc supplementation. The aim of the present study was to determine the dose-response effect of zinc, given as a solution, on iron bioavailability. Twenty-two healthy adult women were selected to participate in the study. Iron, with or without zinc was given as an aqueous solution on d 1,2,14, and 15 of the study. Iron bioavailability was measured on the basis of erythrocyte incorporation of55Fe or59Fe 14 d after administration. Subjects received 0.5 mg of iron together with graded zinc concentrations (0-11.71 mg). No significant effect of zinc on iron absorption was found at Zn : Fe molar ratios up to 2 :1. At 5:1,10:1, and 20 :1 molar ratios, a dose-dependent inhibitory effect on iron absorption was observed (28-40% of iron absorption inhibition; one-way repeated-measures ANOVA, F = 4.48,p = 0.02). In conclusion, zinc administration combined with iron in an aqueous solution leads to the inhibition of iron bioavailability, which occurs in a dose-dependent way. This negative interaction should be considered for supplementation programs with both microminerals.

Escherichia coli isolates from inflammatory bowel diseases patients survive in macrophages and activate NLRP3 inflammasome.

Crohns disease (CD) is a multifactorial pathology associated with the presence of adherent-invasive Escherichia coli (AIEC) and NLRP3 polymorphic variants. The presence of intracellular E. coli in other intestinal pathologies (OIP) and the role of NLRP3-inflammasome in the immune response activated by these bacteria have not been investigated. In this study, we sought to characterize intracellular strains isolated from patients with CD, ulcerative colitis (UC) and OIP, and analyze NLRP3-inflammasome role in the immune response and bactericidal activity induced in macrophages exposed to invasive bacteria. For this, intracellular E. coli isolation from ileal biopsies, using gentamicin-protection assay, revealed a prevalence and CFU/biopsy of E. coli higher in biopsies from CD, UC and OIP patients than in controls. To characterize bacterial isolates, pulsed-field gel electrophoresis (PFGE) patterns, virulence genes, serogroup and phylogenetic group were analyzed. We found out that bacteria isolated from a given patient were closely related and shared virulence factors; however, strains from different patients were genetically heterogeneous. AIEC characteristics in isolated strains, such as invasive and replicative properties, were assessed in epithelial cells and macrophages, respectively. Some strains from CD and UC demonstrated AIEC properties, but not strains from OIP. Furthermore, the role of NLRP3 in pro-inflammatory cytokines production and bacterial elimination was determined in macrophages. E. coli strains induced IL-1β through NLRP3-dependent mechanism; however, their elimination by macrophages was independent of NLRP3. Invasiveness of intracellular E. coli strains into the intestinal mucosa and IL-1β production may contribute to CD and UC pathogenesis.

Iron status in low-birth-weight infants small and appropriate for gestational age. A follow-up study.

Iron nutrition was measured in 84 low‐birth‐weight infants. At birth, they were assigned to three groups: preterm infants appropriate for gestational age (n= 29); preterm infants small for gestational age (n= 17); and full‐term infants* small for gestational age (n= 38). A sub‐sample of infants was supplemented with iron 3 mg/kg from two to four months of age. At birth, preterm appropriate‐for‐gestational‐age infants had a lower hemoglobin concentration than full‐term small‐for‐gestational‐age infants (p < 0.01) and a higher serum ferritin than preterm small‐for‐gestational‐age infants (p < 0.05). In the non‐supplemented group, full‐term small‐for‐gestational‐age infants had significantly higher hemoglobin concentrations at four months of age. At this age, iron‐supplemented preterm infants appropriate or small for gestational age had significantly higher hemoglobin levels than non‐supplemented subjects, while iron supplementation did not have an effect on final hemoglobin concentration in full‐term small‐for‐gestational‐age infants. We conclude that preterm infants, irrespective of their adequacy for gestational age, show evidence of iron deficiency before four months of age. Full‐term infants do not develop iron deficiency up to this age.

Prevention of iron deficiency by milk fortification. The Chilean experience.

Olivares, M., Walter, T., Hertrampf, E., Pizarro, F. and Stekel, A. (Hematology Unit, Institue of Nutrition and Food Technology, University of Chile, Santiago, Chile). Prevention of iron deficiency by milk fortification. The Chilean experience.

The Gastrointestinal Tract and Acute Effects of Copper in Drinking Water and Beverages

Copper is an essential element for all living beings. Exposure to copper results almost exclusively from the ingestion of food and water. Generally, potable water contains low levels of copper, but high concentrations of this mineral have been found in water from private wells or when water or beverages with low pH have been conducted through copper piping. Some authors have associated acute gastrointestinal symptoms (diarrhea, abdominal pain, nausea, and vomiting) with elevated levels of copper in water or beverages, but without excluding other confounding factors that could produce such symptoms. Recently, various controlled studies have demonstrated that a concentration of 2 mg Cu/L of potable water does not produce an increase in gastrointestinal symptoms in infants, and that in women, only concentrations greater than 3 mg Cu/L increase the number of episodes of nausea, vomiting, and abdominal pain, but not diarrhea. This critical analysis of scientific publications verifies the WHO provisional level for copper in drinking water (2 mg/L) as safe for human health.

Evolución de la ingesta y del estado nutricional de zinc, hierro y cobre en mujeres sometidas a cirugía bariátrica hasta el segundo año postoperatorio

INTRODUCTION Bariatric surgery allows a significant reduction in weight and improvement of comorbidities associated with obesity in the long term, but it can also adversely affect the nutritional status of some micronutrients. OBJECTIVES To evaluate changes in intake and parameters of nutritional status of zinc, iron and copper in patients undergoing Roux-en-Y gastric bypass (GBP) or sleeve gastrectomy (SG), until the second postoperative year. METHODS We prospectively studied 45 women undergoing GBP or SG (mean age 35.2 ± 8.4 years, mean BMI 39.8 ± 4.0 kg/m²), every 6 months We measured intake and status indications nutritional zinc, iron and copper, and annually evaluated body composition. The contribution of minerals through supplements represented twice the recommended intake for a healthy woman in patients undergoing GT and three times for GBP. RESULTS 20 women underwent GBP and 25 SG. In both groups there was a significant reduction in weight and body fat percentage, which was maintained until the second postoperative year. Women who have had a greater commitment GBP nutritional status of zinc, iron and copper, that patients undergoing SG. CONCLUSIONS Gastric bypass Roux-Y produces a greater commitment of nutritional status of zinc, iron and copper sleeve gastrectomy. It should evaluate whether administration of supplementation fractional improve the absorption of these nutrients.

Blood biochemical indicators in young and adult Cebus apella of both sexes

Background  A frequent drawback in physiology of non‐human primates is that normal values for a variety of indicators (haematological, biochemical and others) are scant.

Erythrocyte CuZn superoxide dismutase activity is decreased in iron-deficiency anemia

Iron and copper and essential microminerals that are intimately related. The present study was performed to determine the effect of iron-deficiency anemia (IDA) and treatment with iron on laboratory indicators of copper status. Hemoglobin, mean corpuscular volume erythrocyte Zn protoporphyrin, serum ferritin, serum copper, serum ceruloplasmin, and erythrocyte CuZn-superoxide dismutase (SOD) activity were studied in 12 adult women with IDA before and after iron treatment for 60–90 d (100 mg/d Fe, as ferric polymaltose) and in 27 women with normal iron status. Prior to treatment with iron, serum copper and ceruloplasmin were not different between the groups and treatment with iron did not affect these measures. IDA women, before and after treatment with iron, presented a 2.9- and 2-fold decrease in erythrocyte CuZn-SOD activity compared to women with normal iron status (p <0.001). Treatment with iron increased erythrocyte CuZn-SOD activity of the IDA group; however, this change was not statistically significant. in conclusion, CuZn-SOD activity is decreased in IDA. Measurement of this enzyme activity is not useful for evaluating copper nutrition in iron-deficient subjects.

Folic acid nutrition in marasmic infants

Abstract To determine the prevalence of low folic acid levels in infants with marasmic malnutrition and to study its response to daily supplements of folic acid, a group of 80 malnourished infants 2 to 22 months of age were studied. In 12.5% of the group, serum folic acid levels were under 3ug/l and in 16.3%, red cell folic acid levels were under 140ug/l. In a sub group of 28 infants we determined the levels of folic acid on admission and discharge from a nutritional recovery center. During their hospital stay (median 117 days with a range of 94 to 130) infants received exclusively cows milk with a daily supplement of 100ug of folic acid. On discharge, a significant increase of serum folic levels to normal values was observed. A similar improvement, but not to the same extent, was appreciated in red cell folates. Inadequate quantity of supplementation or short time of observation could explain the lack of complete correction in the erythrocyte folic concentration.