Iron Metabolism: New Biomarkers Implicated
- Pp. 80-120 (41)Ana Hernando- Holgado and M. Pilar Gallego-Hernanz
Human organisms require sufficient amounts of iron to satisfy metabolic needs and to accomplish specialized functions such as erythropoiesis, cellular immune response and oxidative metabolism. Despite its abundance, iron physico-chemical properties (practically insoluble at neutral pH under aerobic conditions) hinder its availability and thus specific ligands have evolved for absorption, transport and storage. Iron plays a corner-stone role both in erythropoiesis and inflammation. Iron deficit leads to anemia, but this deficit can be functional (with normal storage) or a true lack of iron: the accuracy of diagnosis results in a completely different treatment. Correct assessment of iron metabolism allows to diagnose and treat (not only in treatment decision-making, but. also predicting and assessing response to treatment) anemia. In this chapter, we review principal biomarkers related to iron metabolism as hemoglobin (whose levels are used as a measure of anemia), ferritin (related to iron storage and inflammation), hepcidin (related mainly to inflammation), transferrin and its receptors and other proteins involved in absorption and transport. Finally we review the phases of iron deficiency and its main clinical manifestation: anemia, both ferropenic and inflammation anemia, as well as clinical implication of iron overload.