![]() The radicals generated in these so-called Fenton or Fenton-like reactions can cause oxidative damage and induce lipid peroxidation and tissue injury. Divalent ferrous iron (Fe 2+) is a cation capable of reacting with hydrogen peroxide generating one of the reactive oxygen species (ROS), the hydroxyl radical while being oxidized to Fe 3+. ![]() ![]() Although iron is essential for the functioning of human physiology, iron also has the potential to be toxic in the presence of hydrogen peroxide (H 2O 2). With the capability of donating and accepting electrons, metal can be found in two oxidation states in the human body. On top of these diverse roles, iron incorporated into heme is the main component of hemoglobin (Hb) and is thus crucial for oxygen transport and supply by erythrocytes. This metal plays a vital role in several cellular processes such as DNA synthesis, nucleic acid repair, cellular respiration in mitochondria, cell growth and cell death and contributes to host defense and cell signaling. Therefore, iron is one of the most important metals to sustain life from single cell bacteria to multi-cellular organisms such as humans. As a transition metal, its ability to donate and accept electrons in redox reactions, makes it favorable for fundamental biological processes. Iron (Fe) is one of the most abundant elements of the Earth’s crust. This review summarizes the key mechanisms and players involved in cellular and systemic iron regulation. In response to an increased iron load, hepatocytes secrete the peptide hormone hepcidin, which binds to and induces internalization and degradation of the iron transporter FPN, thus controlling the amount of iron released from the cells into the blood. While most of the physiologically active iron is bound hemoglobin, the major storage of most iron occurs in the liver in a ferritin-bound fashion. Dietary iron is taken up by the divalent metal transporter 1 (DMT1) in enterocytes and transported to portal blood via ferroportin (FPN), where it is bound to transferrin and taken up by hepatocytes, macrophages and bone marrow cells via transferrin receptor 1 (TfR1). Iron from senescent red blood cells is recycled by macrophages in the spleen, liver and bone marrow. Most of the body’s iron is bound to hemoglobin in erythrocytes. Iron is a critical metal for several vital biological processes.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |