Hormones hepcidin

The absorption efficiency of non-heme iron in particular is also inversely related to iron status. The factor responsible for communicating body iron status to the enterocyte to allow for the up- or downregulation of iron absorption remained elusive until recently, when the hormone hepcidin was identified. Hepcidin declines during iron deficiency, and its decline is associated with an increased production of the DMT-1 and ferroportin transporters in a rat model, although its exact mode of action is unknown. Hepcidin may also regulate iron absorption and retention or release of iron from body stores during conditions of enhanced erythropoiesis and inflammation. 

A Peptide Hormone Synthesized in Liver, Hepcidin, Coordinates Mammalian Iron Physiology... 

Recently, a peptide hormone known as hepcidin has been imphcated as a major circulating molecule that coordinates iron metabolism responses in the reticuloendothehal system and the duodenum. The presence of a circulating factor helps to explain how sites that are physically distant from one another, such as the duodenum and spleen, can coordinately regulate the amount of iron that they release into the bloodstream. Hepcidin negatively regulates iron absorption through the small intestine, iron transport across the placenta,... 

Finally, the hairpin-like peptides, hepcidins, isolated from human urine and liver [120], and from the gill of hybrid striped bass [121], are more complex, with eight cysteine residues forming four disulphide bridges. They form an unusual distorted P-sheet. Interestingly, besides their antimicrobial activity, hepcidins are the principal hormonal-regulators of iron homeostasis in humans [124]. 

VERGA FALZACAPPA MV, MUCKENTHALER MU. Hepcidin iron-hormone and antimicrobial peptide. Gene 2005 Dec 30 364 37 4. 

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