Eisen – Grundsätzliche Rolle im Körper und bei renaler Anämie

Zusammenfassung

Eisen ist ein äußerst wichtiges Spurenelement, das für die Aufrechterhaltung zahlreicher Lebensvorgänge inklusive des Energie- und Atemhaushaltes unerlässlich ist. Eisen wird im Körper vor allem über die Darmresorption reguliert und in der Leber im Wesentlichen gespeichert. Eisen wird hocheffektiv über Makrophagen wiederverwertet. Vor einigen Jahren hat man das Hormon Hepcidin identifiziert, das zentral für die Steuerung der Eisenhomöostase relevant ist. Hepcidin wird aufgrund verschiedener Stimuli wie Inflammation bzw. Eisenüberladung hochreguliert, wohingegen eine Reduzierung bei Anämie, Eisenmangel oder auch Hypoxie besteht. Bei chronischer Niereninsuffizienz zeigen sich aufgrund der fehlenden renalen Elimination und auch der Inflammation erhöhte Hepcidinspiegel, die zur Dysregulation des Eisenhaushaltes und damit auch zur renalen Anämie beitragen. Ziel dieser Übersicht ist es, die Eisenhomöostase und die Regulation von Hepcidin darzustellen.

Summary

Iron is a highly relevant trace element which is essential for the proper function of many essential life processes, including energy und breathing control. Iron is resorbed in the intestine and is mainly stored in the liver. Iron is efficiently recycled in macrophages. Some years ago, hepcidin was identified as a central peptide hormone which regulates iron homeostasis. Hepcidin can be controlled by various stimuli. Inflammation and high iron load regulate hepcidin levels down, whereas anemia, iron deficiency or hypoxia decreases hepcidin levels. In chronic renal failure, there is a reduced excretion of hepcidin and also an increase in hepcidin levels by chronic inflammtion. As a consequence, there is a dysregulation of iron homeostasis and this also leads to renal anemia. The purpose of the current review is to give information of iron homeostasis and to discuss the relevant regulatory role of hepcidin.

Key words

iron - role - renal anemia - hepcidin - homeostasis

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