Iron overload
Normal plasma contains very little ferritin. Ferritin in plasma is elevated in iron overload. Thus ferritin level in blood is an index of body iron stores. iv. Ferritin is an acute phase reactant protein that is elevated in inflammatory diseases. Estimation of ferritin is also indicated in chronic kidney disease to assess the extent of anemia. v. Synthesis of TfR and ferritin and that of ferritin are reciprocally controlled. Both are controlled by the iron content. When iron levels are high, ferritin is synthesized to store the iron; but the TfR synthesis is blocked. When iron levels are high, iron binds to iron-response-element- binding-protein (IREBP), preventing it from binding to IRE. This will result in synthesis of new ferritin, and suppression of synthesis of TfR. Transferrin receptors (TfR) are present on most of the body cells, especially on cells which synthesize heme. The iron-transferrin complex is taken up by the body cells by the receptor mechanism. The transferrin receptor has a molecular weight of 200 kD. It binds two molecules of transferrin. The iron-transferrin- receptor is internalized. Iron is taken in by the cells, and receptor molecules are externalized. vii. Transferrin is a glycoprotein. Abnormal glycosylation is seen in congenital disorders and in chronic alcohol abuse.Ref: DM Vasudevan, page no: 425
Cannot occur because very efficient excretory mechanism are available
Occur in a deficiency of ferroxidase I
Would be accompanied by an increase in total serum transferrin
Might be caused by an ingestion of large amounts of iron along with alcohol
nutrition and digestion