Review Article The liver: conductor of systemic iron balance

Iron is a micronutrient essential for almost all organisms: bacteria, plants, and ani-mals. It is a metal that exists in multiple redox states, including the divalent fer-rous (Fe21) and the trivalent ferric (Fe31) species. The multiple oxidation states of iron make it excellent for electron transfer, allowing iron to be selected during evolu-tion as a cofactor for many proteins involved in central cellular processes in-cluding oxygen transport, mitochondrial respiration, and DNA synthesis. However, the redox cycling of ferrous and ferric iron in the presence of H2O2, which is physio-logically present in the cells, also lead