May 11, 2010 In many anemias, additional sources of iron from diet and tissue stores are needed to meet the erythroid demand. Among a subset of anemias that arise from ineffective erythropoiesis, iron absorption and accumulation in the tissues increases to levels that are in excess of erythropoiesis demand even in the absence of transfusion. Oct 22, 2015 absorption. Thus iron supply to erythropoiesis is strictly dependent on the iron-regulatory hormone hepcidin that controls both macrophage and enterocyte ferroportin (SLC40A1)-mediated export activity (Hentze et al, 2010). Hepcidin regulation is nely tuned according to circulating and stored iron through a hormonal homeostatic mecha-nism.