How Cells Get Their Iron From The Body
As discussed above, 60% or more of the iron in the body is located in hemoglobin molecules of red blood cells, and much of the rest is in ferritin storage form in the liver and other places, the amount of this varying widely between persons. When red blood cells reach a certain age, they are degraded and engulfed by specialized scavenging macrophages. These cells internalize the iron-containing hemoglobin, degrade it, put the iron onto transferrin molecules, and then export the transferrin-iron complexes back out into the blood. Most of the iron used for blood cell production comes from this cycle of hemoglobin recycling.
All cells use some iron, and must get it from the circulating blood. Since iron is tightly bound to transferrin, cells throughout the body have receptors for transferrin-iron complexes on their surfaces. These receptors engulf and internalize both the protein and the iron attached to it through receptor-mediated endocytosis. Once inside, the cell transfers the iron to ferritin, the internal iron storage molecule which is present in all cells.
Transferrin receptor production will increase, and ferritin production will decrease.
Read more about this topic: Human Iron Metabolism
Famous quotes containing the words cells, iron and/or body:
“The twelve Cells for Incorrigibles ... are also carved out of the solid rock hill. On the walls of one of the cells human “liberty” is clearly inscribed, with the “liberty” in significant quotation marks.”
—Administration in the State of Ariz, U.S. public relief program (1935-1943)
“For us she is not the iron lady. She is the kind, dear Mrs. Thatcher.”
—Alexander Dubcek (b. 1921)
“And so I look on those sentiments which make the glory of the human being, love, humility, faith, as being also the intimacy of Divinity in the atoms; and, that, as soon as the man is right, assurances and previsions emanate from the interior of his body and his mind; as, when flowers reach their ripeness, incence exhales from them, and, as a beautiful atmosphere is generated from the planet by the averaged emanations from all its rocks and soils.”
—Ralph Waldo Emerson (1803–1882)