Iron Metabolism in Normal and Pathological Conditions

This review describes modern conceptions of the physiological and pathological roles of iron, as well as the main mechanisms of iron metabolism regulation. In recent years, it has been shown that both deficiency and excess of iron can have damaging effects on the body, and the existence of homeostatic mechanisms controlling the total iron content of the body has been proved. The body of an average healthy adult human contains 3 to 5 g iron, most of which is contained in blood cells, bone marrow and liver; it is bound to proteins and this is important for prevention of cytotoxic effects of free iron ions. This review summarizes data on the main proteins involved in iron metabolism and their role in iron homeostasis. The processes of iron recirculation and the functional role of hepcidin, the key protein regulating extracellular iron concentration, are emphasized. The review provides brief data on pathogenic mechanisms of functional iron deficiency development and its role in anemia of chronic disease, as well as the pathogenesis, diagnostics and management of secondary iron overload.