الفهرس | Only 14 pages are availabe for public view |
Abstract The liver plays an important role in the biochemical metabolism of the body and has various functions, such as the production of glucose, proteins and lipids, and the secretion and excretion of the bile and other waste products. Liver diseases have expanded dramatically in the past decade, partly because of the current epidemic of hepatitis C, which infected millions of people through contaminated blood transfusion. Approximately 20% of these patients are destined to develop cirrhosis or hepatocellular carcinoma, in addition to fulminant hepatic failure, which is a multi factorial process leading to disturbance of essential functions such as acid base balance, energy supply and thermoregulation. If not rapidly reversed, complications will lead to hepatic coma by affecting the brain and kidneys. With additional organ failure, recovery becomes impossible and leads to a high patient mortality. The catastrophic failure of pervious normal liver is one of the most challenging emergencies in clinical medicine. Recent progress in cell biology, resulting in isolation and characterization of stem cells and progenitor cells,increased expectation for a new approach to the treatment of liver diseases. Stem cells are unspecialized cells that can renew themselves and can also differentiate into more mature cells with specialized functions. Two main categories of mammalian stem cells are adult stem cells and embryonic stem cells. Embryonic stem cells are derived from inner cell mass of blastocysts in the early stage embryo. On the other hand, the adult stem cells are undifferentiated cells that occur in a differentiated tissue such as bone marrow or brain in the adult body. Adult stem cells can also be extracted from umbilical cord blood and placenta. |