Iron
Iron is an essential element for human beings. The control of this necessary but potentially toxic substance is an important part of many aspects of human health and disease. Hematologists have been especially interested in the system of iron metabolism because iron is essential to red blood cells. In fact, most of the human body's iron is contained in red blood cells' hemoglobin, and iron deficiency is the most common cause of anemia.
When body levels of iron are too low, then hepcidin in the duodenal epithelium is decreased. This causes an increase in ferroportin activity, stimulating iron uptake in the digestive system. An iron surplus will stimulate the reverse of this process.
In individual cells, an iron deficiency causes responsive element binding protein (IRE-BP) to bind to iron responsive elements (IRE) on mRNAs for transferrin receptors, resulting in increased production of transferrin receptors. These receptors increase binding of transferrin to cells, and therefore stimulating iron uptake.
Read more about this topic: Human Homeostasis
Famous quotes containing the word iron:
“Industrial man—a sentient reciprocating engine having a fluctuating output, coupled to an iron wheel revolving with uniform velocity. And then we wonder why this should be the golden age of revolution and mental derangement.”
—Aldous Huxley (1894–1963)
“With our principles we seek to rule our habits with an iron hand, or to justify, honor, scold, or conceal them:Mtwo men with identical principles are likely to be seeking fundamentally different things with them.”
—Friedrich Nietzsche (1844–1900)
“Manhattan. Sometimes from beyond the skyscrapers, across the hundreds of thousands of high walls, the cry of a tugboat finds you in your insomnia in the middle of the night, and you remember that this desert of iron and cement is an island.”
—Albert Camus (1913–1960)