[Alcoholic liver cirrhosis].
In alcoholic liver disease, it is well-known that ethanol and its metabolites induce hepatic fibrosis. With progress in injury, the accumulation of extracellular matrix, which consists of type I, III, IV collagen and laminine, occurs in the area of hepatic central vein and perihepatocytes. In these fibrotic areas, the activated lipocytes (transitional cell and myofibroblast, etc), which may be transformed from Ito cell by fibrogenic cytokines, are increased and may play an important role in the progression of alcoholic hepatic fibrosis. Actually, a recent study indicates that chronic ethanol consumption sensitizes the response of lipocytes to TGF beta. It is observed that acetaldehyde and lactate stimulate collagen production and that acetaldehyde increases collagen mRNA expression and collagen gene transcription in cultured human fibroblast. The extracellular matrix is degraded by matrix metalloproteinases (MMPs). The collagenase activity is decreased in progression of liver cirrhosis and is regulated by fibrogenic cytokines. Acetaldehyde decreases by 50% of the collagenase mRNA expression in fibroblast. It is clear that hepatic fibrosis may progress under the balance of collagen production and degradation, which are associated with fibrogenic cytokines. Thus, in the search for mechanism of alcoholic hepatic fibrosis, it is important to elucidate how ethanol and its metabolites influence the activation of lipocytes through fibrogenic cytokines.
Ishii
H
H
Division of Gastroenterology, School of Medicine, Keio University.
Arai
M
M
D000818:Animals; D003094:Collagen / Q000378:metabolism; D016207:Cytokines / Q000502:physiology; D005355:Fibrosis; D006801:Humans; D008099:Liver / Q000166:cytology / Q000378:metabolism / Q000473:pathology*; D008104:Liver Cirrhosis, Alcoholic / Q000378:metabolism / Q000473:pathology*; D008666:Metalloendopeptidases / Q000502:physiology
D016207:Cytokines; D003094:Collagen; D008666:Metalloendopeptidases