| Abstract
| - Iron chelates, namely, ferrous bisglycinate and ferric EDTA, are promising alternatives to iron saltsfor food fortification. The objectives of this study were to compare iron uptake from radiolabeled ferroussulfate, ferrous ascorbate, ferrous bisglycinate, ferric chloride, ferric citrate, and ferric EDTA by Caco-2cells with different iron status and in the presence of divalent metal cations. Iron-loaded Caco-2 cells,with reduced DMT-1 and elevated HFE mRNA levels, down-regulated uptake from ferrous ascorbateand bisglycinate but not from ferric compounds. Nevertheless, iron uptake from all compounds wasmarkedly inhibited in the presence of 100-fold molar excess of Co2+ and Mn2+ cations, with ferrouscompounds showing a greater percent reduction. Our results suggest that ferrous iron is thepredominant form of iron taken up by intestinal epithelial cells and the DMT-1 pathway is the majorpathway for uptake. Iron uptake from chelates appears to follow the same pathway as uptake fromsalts. Keywords: Iron uptake; Caco-2; DMT-1; HFE; EDTA; bisglycinate; chelates
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