In which of the following conditions is the synthesis of hepcidin not reduced ?
Inorganic iron is transported into the mucosal cell by a proton-linked divalent metal ion transporter, and accumulated intracellularly by binding to ferritin. Iron leaves the mucosal cell via a transport protein  ferroportin, but only if there is free transferrin in plasma to bind to. Once transferrin is saturated with iron, any that has accumulated in the mucosal cells is lost when the cells are shed. Expression of the ferroportin gene (and possibly also that for the divalent metal ion transporter) is downregulated by hepcidin, a peptide secreted by the liver when body iron reserves are adequate.
In response to hypoxia, anemia, or hemorrhage, the synthesis of hepcidin is reduced, leading to increased synthesis of ferroportin and increased iron absorption. As a result of this mucosal barrier, only ∼10% of dietary iron is absorbed, and only 1% to 5% from many plant foods.
Hemosiderosis is an iron overload condition and further iron absorption is not required.
HARPERS ILLUSTRATED BIOCHEMISTRY30th ed. page no.541
Hypoxia
Anemia
Hemorrhage
Hemosiderosis