In a new discovery, the research team has revealed an unknown clockwork mechanism within the body that controls the creation of oxygen-carrying red blood cells. The finding sheds light on iron-restricted anaemias that leave millions of people weak, tired and unable to concentrate – and it may point the way to better treatments as well.
The researchers made the discovery while seeking to better understand why iron-restricted anaemias cause the body to create insufficient numbers of vital red blood cells. While examining bone marrow cells, they found that the cells contained large pools of the receptor for erythropoietin, a hormone that directs the bone marrow to make red blood cells (The hormone known as EPO).
To do its job receiving the instruction to make blood cells, the receptor must be on the outside of the marrow cells. Yet so much was stored up inside them. This might explain why some people's bone marrow cells fail to follow the hormone's instructions.
Researcher Lorrie Delehanty was studying anaemia using a model the lab developed ‘anemia in a dish’, the scientists call it. If you drop the iron level way down, these cells act like anaemic cells. They basically become anaemic cells – they even look very pale. Something else happens, too, she noticed: A particular protein disappeared.
The Scribble protein (named after the SCRIB gene that produces it) proved to be a key piece of the clockwork mechanism. Basically, the amount of iron in the blood affects the amount of the Scribble protein available, and Scribble controls whether the hormone receptor is welled up inside the bone marrow cells or doing its job on the outside.
The research team realized that this was kind of a complicated symphony that starts with iron and ultimately controls how much and what kind of messages the cells get. The researchers used this knowledge to fix EPO resistance in their model, and they hope the discovery will eventually be useful for treating anaemias in people, too.
Researcher Goldfarb said, "We have got the key components, and we want to move up the hierarchy to the master regulatory element that is controlling this. This will get us that much closer to alternative treatments for anaemia."