![]() membrane components, such as phosphatidylserine, or free haem. These new therapies could target various components of the red blood cell microparticles, e.g. These innovative results make it possible to anticipate new therapeutic possibilities for preventing and treating vaso-occlusive crises, as well as for preventing some more common cardiovascular diseases. These microparticles also probably contribute to the many lesions caused by chronic lack of oxygen, e.g. In patients with sickle cell disease, red blood cell fragments may be partly responsible for very painful vaso-occlusive crises. This also leads to oxidative stress and promotes obstruction of the blood vessels. This transfer of haem and iron from the red blood cells to the vascular lining interferes with dilation, limiting the blood supply to the tissues that need it. It is this feature that makes the microparticles dangerous.Įffectively, the red blood cell particles act as carriers, and deposit the toxic substances on the cells lining the blood vessels. As a result, the red blood cell fragments also contain haemoglobin, but in a degraded and toxic form: the iron previously contained in the haemoglobin becomes exposed on the surface of these thousands of red blood cell microparticles. Red blood cells contain haemoglobin, the protein that carries blood gases and enables us to breathe. Their rigidity leads to a considerable degree of haemolysis, which is therefore easier to study. These observations were made using red blood cells from patients with sickle cell disease, the most common genetic disorder in France. Researchers led by Olivier Blanc-Brude, a CNRS (French National Centre for Scientific Research) research fellow at the Inserm Paris Cardiovascular Center and Paris Descartes University, have just shown that at the exact moment of haemolysis, the red blood cells do not disappear: they actually release a large number of fragments, known as microparticles. They ultimately rupture and release their contents, a process referred to as intravascular haemolysis.ĭoes the red blood cell disappear then? Not quite… But abnormal red blood cells persist in the bloodstream in some diseases. Their stock is constantly renewed, and each one is discreetly removed every three months. ![]() There are approximately 5 million red blood cells in every microlitre of blood. yeah, the main point of all this is: yes, RBCs do have a membrane, and they are far more important to them than to other cells.A new study published in the journal Blood shows that red blood cells can turn against blood vessels by releasing aggressive fragments that contribute to the development of cardiovascular diseases. Consecutively, this ensures that they can securely transport adequate oxygen to all our cells and keep them alive. This in turn facilitates oxygen uptake by the RBCs, as the larger surface area an RBC has means that it can receive a much larger amount of diffused oxygen in the lungs than other cells, were other cells to take oxygen in the same manner. RBCs have a biconcave shape, which means that they have a larger surface area of cell membranes than a usual ellipsoid cell. In fact, cell membranes are vitally important to red blood cells from the point of view of diffusion, active transport and the huge surface area the cell surface membrane provides for that. Red blood cells, even though they look weirdly shaped, do have a cell membrane.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |