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Richard F Hurrell - One of the best experts on this subject based on the ideXlab platform.
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iron bioavailability in 8 24 month old thai children from a micronutrient fortified quick cooking rice containing Ferric Ammonium Citrate or a mixture of ferrous sulphate and Ferric sodium ethylenediaminetetraacetic acid
Maternal and Child Nutrition, 2015Co-Authors: Visith Chavasit, Suparat Porasuphatana, Umaporn Suthutvoravut, Christroph Zeder, Richard F HurrellAbstract:: A quick-cooking rice, produced from broken rice, is a convenient ingredient for complementary foods in Thailand. The rice is fortified with micronutrients including iron during the processing procedure, which can cause unacceptable sensory changes. A quick-cooking rice fortified with Ferric Ammonium Citrate (FAC) or a mixture of ferrous sulphate (FeSO4 ) and Ferric sodium ethylenediaminetetraacetic acid (NaFeEDTA), with a 2:1 molar ratio of iron from FeSO4 : iron from NaFeEDTA (FeSO4 + NaFeEDTA), gave a product that was organoleptically acceptable. The study compared iron absorption by infants and young children fed with micronutrient-fortified quick-cooking rice containing the test iron compounds or FeSO4 . Micronutrient-fortified quick-cooking rice prepared as a traditional Thai dessert was fed to two groups of 15 8-24-month healthy Thai children. The iron fortificants were isotopically labelled with (57) Fe for the reference FeSO4 or (58) Fe for the tested fortificants, and iron absorption was quantified based on erythrocyte incorporation of the iron isotopes 14 days after feeding. The relative bioavailability of FAC and of the FeSO4 + NaFeEDTA was obtained by comparing their iron absorption with that of FeSO4 . Mean fractional iron absorption was 5.8% [±standard error (SE) 1.9] from FAC and 10.3% (±SE 1.9) from FeSO4 + NaFeEDTA. The relative bioavailability of FAC was 83% (P = 0.02). The relative bioavailability of FeSO4 + NaFeEDTA was 145% (P = 0.001). Iron absorption from the rice containing FAC or FeSO4 + NaFeEDTA was sufficiently high to be used in its formulation, although iron absorption from FeSO4 + NaFeEDTA was significantly higher (P < 0.00001).
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Iron absorption by human subjects from different iron fortification compounds added to Thai fish sauce.
European journal of clinical nutrition, 2005Co-Authors: T Walczyk, S Tuntipopipat, C Zeder, P Sirichakwal, E Wasantwisut, Richard F HurrellAbstract:(a) To measure iron absorption by human subjects from citric acid stabilized fish sauce fortified with ferrous sulfate, Ferric Ammonium Citrate or ferrous lactate and (b) to identify the effect of added citric acid (3 g/l) on iron absorption from ferrous sulfate fortified fish sauce. Iron absorption from the intrinsically labeled compounds was determined via erythrocyte incorporation of isotopic labels (57Fe and 58Fe) using a randomized crossover design. In three separate absorption studies, 10 adult women each consumed a basic test meal of rice and vegetable soup seasoned with isotopically labeled, iron fortified fish sauce. Iron absorption was significantly lower from ferrous lactate and from Ferric Ammonium Citrate fortified fish sauce than from ferrous sulfate fortified fish sauce. Fractional iron absorption (geometric mean; −1s.d., +1s.d.) was 8.7(3.6; 21.4)% for ferrous lactate compared to 13.0(5.4; 31.4)% from ferrous sulfate, P=0.003 (study 1) and 6.0(2.5; 14.3)% from Ferric Ammonium Citrate relative to 11.7(4.4; 30.7)% from ferrous sulfate, P
Des R. Richardson - One of the best experts on this subject based on the ideXlab platform.
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Iron and gallium increase iron uptake from transferrin by human melanoma cells: further examination of the Ferric Ammonium Citrate-activated iron uptake process.
Biochimica et biophysica acta, 2001Co-Authors: Des R. RichardsonAbstract:Abstract Previously we showed that preincubation of cells with Ferric Ammonium Citrate (FAC) resulted in a marked increase in Fe uptake from both 59 Fe-transferrin (Tf) and 59 Fe-Citrate (D.R. Richardson, E. Baker, J. Biol. Chem. 267 (1992) 13972–13979; D.R. Richardson, P. Ponka, Biochim. Biophys. Acta 1269 (1995) 105–114). This Fe uptake process was independent of the transferrin receptor and appeared to be activated by free radicals generated via the iron-catalysed Haber-Weiss reaction. To further understand this process, the present investigation was performed. In these experiments, cells were preincubated for 3 h at 37°C with FAC or metal ion solutions and then labelled for 3 h at 37°C with 59 Fe-Tf. Exposure of cells to FAC resulted in Fe uptake from 59 Fe-Citrate that became saturated at an Fe concentration of 2.5 μM, while FAC-activated Fe uptake from Tf was not saturable up to 25 μM. In addition, the extent of FAC-activated Fe uptake from Citrate was far greater than that from Tf. These results suggest a mechanism where FAC-activated Fe uptake from Citrate may result from direct interaction with the transporter, while Fe uptake from Tf appears indirect and less efficient. Preincubation of cells with FAC at 4°C instead of 37°C prevented its effect at stimulating 59 Fe uptake from 59 Fe-Tf, suggesting that an active process was involved. Previous studies by others have shown that FAC can increase ferrireductase activity that may enhance 59 Fe uptake from 59 Fe-Tf. However, there was no difference in the ability of FAC-treated cells compared to controls to reduce Ferricyanide to ferrocyanide, suggesting no change in oxidoreductase activity. To examine if activation of this Fe uptake mechanism could occur by incubation with a range of metal ions, cells were preincubated with either FAC, Ferric chloride, ferrous sulphate, ferrous Ammonium sulphate, gallium nitrate, copper chloride, zinc chloride, or cobalt chloride. Stimulation of 59 Fe uptake from Tf was shown (in order of potency) with Ferric chloride, ferrous sulphate, ferrous Ammonium sulphate, and gallium nitrate. The other metal ions examined decreased 59 Fe uptake from Tf. The fact that redox-active Cu(II) ion did not stimulate Fe uptake while redox-inactive Ga(III) did, suggests a mechanism of transporter activation not solely dependent on free radical generation. Indeed, the activation of Fe uptake appears dependent on the presence of the Fe atom itself or a metal ion with atomic similarities to Fe (e.g. Ga).
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Two mechanisms of iron uptake from transferrin by melanoma cells. The effect of desferrioxamine and Ferric Ammonium Citrate.
The Journal of biological chemistry, 1992Co-Authors: Des R. Richardson, Erica BakerAbstract:The effects of Ferric Ammonium Citrate (FAC) and desferrioxamine (DFO) on iron (Fe), and transferrin (Tf) uptake have been investigated using SK-MEL-28 human melanoma cells, which express the Tf homologue, melanotransferrin, in high concentrations. Previously we demonstrated two separate Fe uptake mechanisms from Tf, viz. a specific process mediated by the transferrin receptor (TfR) and a nonspecific process (Richardson, D. R., and Baker, E. (1990) Biochim. Biophys. Acta 1053, 1-12). Cells exposed to DFO demonstrated up-regulation of the TfR with a concurrent increase in the rate of Fe uptake. Desferrioxamine also stimulated the nonspecific process of Fe uptake, resulting in a further increase in accumulation of Fe over Tf after saturation of the specific TfR. Ferric Ammonium Citrate had two effects. First, it resulted in down-regulation of the TfR. Second, and paradoxically, it markedly stimulated the rate of Fe uptake from Tf by the nonspecific process without increasing the rate of nonspecific Tf uptake. These data conclusively demonstrate that two entirely different mechanisms of iron uptake from Tf exist in melanoma cells and that Ferric Ammonium Citrate may be a useful experimental tool to further characterize the specific and nonspecific mechanisms of Fe uptake from Tf.
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The effect of desferrioxamine and Ferric Ammonium Citrate on the uptake of iron by the membrane iron-binding component of human melanoma cells
Biochimica et biophysica acta, 1992Co-Authors: Des R. Richardson, Erica BakerAbstract:Abstract The effect of Ferric Ammonium Citrate (FAC) and desferrioxamine (DFO) on membrane iron and transferrin uptake have been investigated using SK-MEL-28 human melanoma cells which express the membrane-bound transferrin homologue, melanotransferrin, at high concentrations. Exposure of melanoma cells to DFO increased membrane non-Tf-bound Fe uptake (putative melanotransferrin Fe-binding sites), suggesting upregulation of the membrane Fe-binding component. However, exposure to FAC did not result in down-regulation. Indeed, an increase in non-Tf-bound membrane Fe was apparent. Results suggested that non-Tf-bound membrane Fe uptake occurred by two processes corresponding to the specific and non-specific mechanisms of Fe uptake from Tf described previously (Richardson, D.R. and Baker, E. (1990) Biochim. Biophys. Acta 1053, 1–12).
T Walczyk - One of the best experts on this subject based on the ideXlab platform.
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Iron absorption by human subjects from different iron fortification compounds added to Thai fish sauce
European Journal of Clinical Nutrition, 2005Co-Authors: T Walczyk, S Tuntipopipat, C Zeder, P Sirichakwal, E Wasantwisut, R F HurrellAbstract:Objectives: (a) To measure iron absorption by human subjects from citric acid stabilized fish sauce fortified with ferrous sulfate, Ferric Ammonium Citrate or ferrous lactate and (b) to identify the effect of added citric acid (3 g/l) on iron absorption from ferrous sulfate fortified fish sauce. Design: Iron absorption from the intrinsically labeled compounds was determined via erythrocyte incorporation of isotopic labels (^57Fe and ^58Fe) using a randomized crossover design. In three separate absorption studies, 10 adult women each consumed a basic test meal of rice and vegetable soup seasoned with isotopically labeled, iron fortified fish sauce. Results: Iron absorption was significantly lower from ferrous lactate and from Ferric Ammonium Citrate fortified fish sauce than from ferrous sulfate fortified fish sauce. Fractional iron absorption (geometric mean; −1s.d., +1s.d.) was 8.7(3.6; 21.4)% for ferrous lactate compared to 13.0(5.4; 31.4)% from ferrous sulfate, P =0.003 (study 1) and 6.0(2.5; 14.3)% from Ferric Ammonium Citrate relative to 11.7(4.4; 30.7)% from ferrous sulfate, P
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Iron absorption by human subjects from different iron fortification compounds added to Thai fish sauce.
European journal of clinical nutrition, 2005Co-Authors: T Walczyk, S Tuntipopipat, C Zeder, P Sirichakwal, E Wasantwisut, Richard F HurrellAbstract:(a) To measure iron absorption by human subjects from citric acid stabilized fish sauce fortified with ferrous sulfate, Ferric Ammonium Citrate or ferrous lactate and (b) to identify the effect of added citric acid (3 g/l) on iron absorption from ferrous sulfate fortified fish sauce. Iron absorption from the intrinsically labeled compounds was determined via erythrocyte incorporation of isotopic labels (57Fe and 58Fe) using a randomized crossover design. In three separate absorption studies, 10 adult women each consumed a basic test meal of rice and vegetable soup seasoned with isotopically labeled, iron fortified fish sauce. Iron absorption was significantly lower from ferrous lactate and from Ferric Ammonium Citrate fortified fish sauce than from ferrous sulfate fortified fish sauce. Fractional iron absorption (geometric mean; −1s.d., +1s.d.) was 8.7(3.6; 21.4)% for ferrous lactate compared to 13.0(5.4; 31.4)% from ferrous sulfate, P=0.003 (study 1) and 6.0(2.5; 14.3)% from Ferric Ammonium Citrate relative to 11.7(4.4; 30.7)% from ferrous sulfate, P
Ralf Dringen - One of the best experts on this subject based on the ideXlab platform.
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iron accumulation iron mediated toxicity and altered levels of ferritin and transferrin receptor in cultured astrocytes during incubation with Ferric Ammonium Citrate
Journal of Neurochemistry, 2004Co-Authors: Hans H Hoepken, Till Korten, Stephen R Robinson, Ralf DringenAbstract:The cellular uptake and storage of iron have to be tightly regulated in order to provide iron for essential cellular functions while preventing the iron-catalysed generation of reactive oxygen species (ROS). In contrast to cells in other organs, little is known about the regulation of iron metabolism in brain cells, particularly in astrocytes. To investigate the regulation of iron metabolism in astrocytes we have used primary astrocyte cultures from the brains of newborn rats. After application of Ferric Ammonium Citrate (FAC), cultured astrocytes accumulated iron in a time- (0-48 h) and concentration-dependent (0.01-1 mm) manner. This accumulation was prevented if FAC was applied in combination with the iron-chelator deferoxamine (DFX). Application of FAC to astrocyte cultures caused a strong increase in the cellular content of the iron storage protein ferritin and a decrease in the amount of transferrin receptor (TfR), which is involved in the transferrin-mediated uptake of iron into cells. In contrast, application of DFX strongly increased the level of TfR. Both up-regulation of ferritin content by iron application and up-regulation of TfR content by DFX were prevented by the protein synthesis inhibitor cycloheximide (CHX). During incubation of astrocytes with FAC, a mild and transient increase in the extracellular activity of the cytosolic enzyme lactate dehydrogenase and in the concentration of intracellular ROS was observed. In contrast, prevention of protein synthesis by CHX during incubation with FAC resulted in significantly more cell loss and a persistent and intense increase in the production of intracellular ROS. These results demonstrate that both iron accumulation and deprivation modulate the synthesis of ferritin and TfR in astrocytes and that protein synthesis is required to prevent iron-mediated toxicity in astrocytes.
Erica Baker - One of the best experts on this subject based on the ideXlab platform.
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Two mechanisms of iron uptake from transferrin by melanoma cells. The effect of desferrioxamine and Ferric Ammonium Citrate.
The Journal of biological chemistry, 1992Co-Authors: Des R. Richardson, Erica BakerAbstract:The effects of Ferric Ammonium Citrate (FAC) and desferrioxamine (DFO) on iron (Fe), and transferrin (Tf) uptake have been investigated using SK-MEL-28 human melanoma cells, which express the Tf homologue, melanotransferrin, in high concentrations. Previously we demonstrated two separate Fe uptake mechanisms from Tf, viz. a specific process mediated by the transferrin receptor (TfR) and a nonspecific process (Richardson, D. R., and Baker, E. (1990) Biochim. Biophys. Acta 1053, 1-12). Cells exposed to DFO demonstrated up-regulation of the TfR with a concurrent increase in the rate of Fe uptake. Desferrioxamine also stimulated the nonspecific process of Fe uptake, resulting in a further increase in accumulation of Fe over Tf after saturation of the specific TfR. Ferric Ammonium Citrate had two effects. First, it resulted in down-regulation of the TfR. Second, and paradoxically, it markedly stimulated the rate of Fe uptake from Tf by the nonspecific process without increasing the rate of nonspecific Tf uptake. These data conclusively demonstrate that two entirely different mechanisms of iron uptake from Tf exist in melanoma cells and that Ferric Ammonium Citrate may be a useful experimental tool to further characterize the specific and nonspecific mechanisms of Fe uptake from Tf.
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The effect of desferrioxamine and Ferric Ammonium Citrate on the uptake of iron by the membrane iron-binding component of human melanoma cells
Biochimica et biophysica acta, 1992Co-Authors: Des R. Richardson, Erica BakerAbstract:Abstract The effect of Ferric Ammonium Citrate (FAC) and desferrioxamine (DFO) on membrane iron and transferrin uptake have been investigated using SK-MEL-28 human melanoma cells which express the membrane-bound transferrin homologue, melanotransferrin, at high concentrations. Exposure of melanoma cells to DFO increased membrane non-Tf-bound Fe uptake (putative melanotransferrin Fe-binding sites), suggesting upregulation of the membrane Fe-binding component. However, exposure to FAC did not result in down-regulation. Indeed, an increase in non-Tf-bound membrane Fe was apparent. Results suggested that non-Tf-bound membrane Fe uptake occurred by two processes corresponding to the specific and non-specific mechanisms of Fe uptake from Tf described previously (Richardson, D.R. and Baker, E. (1990) Biochim. Biophys. Acta 1053, 1–12).