Abstract
Background: Hem-iron is the main source of iron intake for humans in developed countries, which is best absorbed than inorganic iron (Fe). Iron deficiency is one of the most prevalent nutritional deficiencies in developing countries. One of the strategies to improve Fe nutrition is to increase hem-Fe intake in the population.
Objective: To study in vitro the mechanisms of hem-Fe uptake and transport at the intestinal cells.
Methods: Caco-2 Cells were grown in Iscove′s media, supplemented with 10% SFB, hem-Fe (Hb-Fe55) (0,1–100 uM Fe). We determined in cellular extracts, total intracellular Fe by AAE and heme oxygenase and DMT1(Divalent Metal Transporter 1) by Western Blot. We studied endocytic process, temperature effect and hem-Fe uptake and transport. The radioactivity was counted in the cells and in basolateral media.
Results: Cells exposed to hem-Fe showed lower intracellular Fe than cells exposed to inorganic Fe. Hem-Fe uptake was inhibited by acidification and K+ depletion. The highest uptake and transport were observed in cells incubated with hem-Fe. Heme oxygenase 1 expression increased and DMT1 expression decreased when hem-Fe increased in the incubation media.
Conclusions: Hem-Fe uptake in the intestinal epithelia cells would be by a inorganic Fe independent mechanism by a saturable and endocytic process dependent. Financing: FONDECYT 1030633 Chile.
Article PDF
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Arredondo, M., Flores, S., Mendiburo, M. et al. 16 Intestinal HEM Iron Uptake is an Endocytic-Mediated Process. Pediatr Res 57, 922 (2005). https://doi.org/10.1203/00006450-200506000-00044
Issue Date:
DOI: https://doi.org/10.1203/00006450-200506000-00044