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Essential Metal Uptake in Gram-negative Bacteria: X-ray Fluorescence, Radioisotopes, and Cell Fractionation
Published on: February 1, 2018
Iron absorption and transport
M E Conrad1, J N Umbreit, E G Moore
1USA Cancer Center, University of South Alabama, Mobile 36688, USA. mconrad@usamail.usouthal.edu
The American Journal of the Medical Sciences
|October 16, 1999
Summary
Iron absorption in the body involves distinct pathways for inorganic iron and heme. Understanding these iron uptake mechanisms is crucial for regulating iron levels and preventing cellular damage.
Area of Science:
- Biochemistry
- Cell Biology
- Physiology
Background:
- Iron is essential for numerous metabolic processes, including oxygen transport and DNA synthesis.
- Careful regulation of iron concentrations is vital to prevent tissue damage from free radicals.
- Intestinal absorption is the primary regulator of body iron levels.
Purpose of the Study:
- To elucidate the distinct pathways involved in intestinal iron uptake.
- To differentiate mechanisms for inorganic iron (ferric and ferrous) and heme iron absorption.
- To describe iron transport into and out of intestinal cells and into non-intestinal cells.
Main Methods:
- Studies utilizing blocking antibodies.
- Observations in rodent models of iron metabolism disorders.
- Experiments with tissue culture cells.
- Analysis of iron transport via transferrin receptor-dependent and independent pathways.
Main Results:
- Separate pathways exist for cellular uptake of ferric iron (mobilferrin-integrin) and ferrous iron (divalent cation transporter-1).
- Heme iron is absorbed via a distinct pathway.
- Iron enters intestinal cells from plasma via transferrin receptors and exits via hephaestin.
- Non-intestinal cells utilize transferrin receptor-dependent and independent pathways for iron uptake, and can also absorb iron salts.
Conclusions:
- Multiple, distinct pathways mediate iron uptake and transport within the body.
- Understanding these pathways is key to managing iron homeostasis and preventing iron-related toxicity.
- Further research is needed to fully describe the mechanisms of certain pathways, such as the transferrin receptor independent pathway (TRIP).
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