Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0023890 (cirrhosis)
 42,195 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The presence and distribution of collagenase in experimental CCl4 cirrhosis of the liver in rats has been studied by immunohistochemical techniques. A monospecific anti-rat uterus collagenase antibody was raised in rabbits and used for indirect immunofluorescence staining of liver sections obtained from rats in both the reversible and irreversible stages of CCl4-induced cirrhosis. Collagenase is present assoicated with connective tissue septums as long as cirrhosis is reversible, and it is not detectable in the irreversible stage. In animals sacrificed during the transition between the reversible and irreversible stages of cirrhosis, collagenase appeared bound to the outer surfaces of connective tissue septums and was absent from the deeper portions. These observation suggest that the irreversibility of experimental CCl4 cirrhosis of the liver is associated with a disturbance in the mechanisms of collagen degradation, which may be a deficiency in collagenase activity, a change in the susceptibility of the substrate, or a combination of both factors.
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PMID:Collagenase in experimental carbon tetrachloride cirrhosis of the liver. 20 92

Percutaneous liver biopsies obtained from patients with a history of chronic alcoholism and normal liver, fatty liver, alcoholic hepatitis, or active cirrhosis were incubated with tritiated proline to determine the pattern of collagen biosynthesis in these conditions. Incorporation of labeled proline and hydroxyproline into salt-soluble and insoluble fractions of collagen was evaluated by radiochemical analysis and tissue localization documented by autoradiography. Biopsy specimens of alcoholic hepatitis and cirrhosis exhibit a significant increase in the amount of radioactive proline and hydroxyproline in salt-soluble and insoluble collagen. Marked accumulation of radioactivity occurred over bile ducts, fibroblasts, and collagen fibers in the portal area and over hepatocytes, fibroblasts, and collagen fibers in the centrilobular area. Fatty liver is associated with an increase in uptake of proline and hydroxyproline in the salt-soluble fraction of collagem; silver grains appear in the periphery of fat-laden cells and in areas of focal inflammation. Digestion by collagenase indicates that labeling over fibroblasts and collagen reflects active synthesis, whereas, entry of proline into the cell protein pool is responsible for accumulation of radioactivity in other sites. In vitro ethanol causes a significant increase in the incorporation of proline and hydroxyproline into collagen in biopsy specimens of alcoholic hepatitis or active cirrhosis, but has no effect on collagen synthesis by normal or fatty liver.
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PMID:Collagen biosynthesis in liver disease of the alcoholic. 117 Feb 67

We recently found that polyunsaturated lecithin prevents ethanol from causing cirrhosis in the baboon. Because transformation of lipocytes to transitional cells plays a key role in hepatic fibrogenesis in vivo, and because this process in alcohol-fed baboons was found to be attenuated by polyunsaturated lecithin, we focused on lipocytes to study the mechanism of the protective effect. Rat lipocytes cultured on plastic undergo spontaneous activation, accompanied by expression of alpha-smooth muscle actin isoform and production of substantial amounts of type I collagen. The latter was further increased on incubation with acetaldehyde. This in vitro model was used here to study how acetaldehyde-mediated collagen production and accumulation can be turned off. Addition of polyunsaturated lecithin (10 mumols/L) was found to prevent the acetaldehyde-induced increase in collagen accumulation by 83% (p less than 0.001). By contrast, a saturated phospholipid (10 mumols/L dilauroyl phosphatidylcholine), a monounsaturated one (10 mumols/L linoleoyl-palmitoyl phosphatidylcholine) or linoleic acid (20 mumols/L bound to albumin) had no such effect. Incorporation of [3H]proline into collagen and the expression of alpha-1 (I) procollagen mRNA were increased by acetaldehyde; the latter was not significantly affected by polyunsaturated lecithin. Polyunsaturated lecithin increased lipocyte collagenase activity by 100% (p less than 0.001), whereas dilauroyl phosphatidylcholine, linoleoyl-palmitoyl phosphatidylcholine and linoleic acid had no such action. We concluded that (a) polyunsaturated lecithin selectively prevents the acetaldehyde-induced increase in collagen accumulation in lipocyte cultures, whereas other phospholipids or linoleate have no such effect; and (b) polyunsaturated lecithin does not modify the acetaldehyde-mediated increase in alpha-1 (I) procollagen mRNA, but it increases collagenase activity, suggesting that the protective effect exerted by polyunsaturated lecithin against alcohol induced fibrosis in vivo is due at least in part to stimulation of collagenase activity, which may prevent excess collagen accumulation by offsetting increased collagen production.
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PMID:Polyunsaturated lecithin prevents acetaldehyde-mediated hepatic collagen accumulation by stimulating collagenase activity in cultured lipocytes. 137 80

Orthotopic liver transplantation as treatment for hereditary enzyme deficiencies in the absence of cirrhosis suffers from significant operative risks, complications, and donor shortages. Transplantation of isolated hepatocytes (HTX) may offer opportunities for the treatment of these diseases and retain the recipient liver. Hepatocytes transplanted into the portal vein, spleen, or omentum lack an ideal growing environment for cell proliferation and maintenance. Therefore, we investigated a method combining 75% recipient hepatectomy with direct injection of hepatocytes into the remaining 25% of liver parenchyma to provide proliferative stimuli and a stable environment during and following liver regeneration. Recipient Gunn rats (glucuronyltransferase deficiency and hyperbilirubinemia) underwent hepatectomy before HTX by direct injection of 10(7) isolated hepatocytes into the remaining parenchyma. Inbred male Wistar and Gunn rats were used as normal and control hepatocyte donors and saline injection served as a sham transplant control. Isolation of donor hepatocytes was performed with a two-step collagenase digestive method (Seglen) with cell viability of 85% to 95%. Liver regeneration was complete by 2 weeks posttransplant. Four weeks following HTX, total serum bilirubin and qualitative bile analysis were performed. A significant decrease in total serum bilirubin levels was observed in Gunn rats receiving Wistar hepatocytes compared with those receiving Gunn hepatocytes and saline control. Bile analysis from HTX rats demonstrated a normal pattern containing bilirubin monoglucuronides and diglucuronides (conjugated bilirubin) in the rats receiving Wistar hepatocytes, whereas the control group receiving Gunn hepatocytes or saline injection demonstrated only unconjugated bilirubin. No differences in histological appearance were noted between groups.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Intrahepatic hepatocyte transplantation following subtotal hepatectomy in the recipient: a possible model in the treatment of hepatic enzyme deficiency. 150 Oct 3

The concentration of the N-terminal peptide of procollagen III and the activity of collagen peptidase (PZ-peptidase) were measured in sera from 92 patients with chronic liver disease. In patients with liver cirrhosis and chronic hepatitis with transformation of liver structure, high values were found for both variables compared with hepatoses and chronic hepatitis without transformation. The concentration of procollagen III peptide and the activity of collagen peptidase in serum increased with increasing degrees of fibrosis and, even more markedly, with increasing degrees of mesenchymal activity in the liver.
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PMID:Collagen peptidase and type III procollagen peptide serum levels in chronic liver diseases. 164 85

In the liver biopsy of 100 patients with chronic liver diseases, the activity of 7-ethoxycoumarin O-deethylase (ECOD) was determined as a parameter of hepatic monooxygenase system and was compared with some markers of fibrosis e.g. collagen peptidase and hydroxyproline. ECOD was significantly different in healthy liver, fatty liver, chronic active hepatitis (CAH) and cirrhosis. The importance of the fibrotic process was shown by the significant correlations between ECOD and the signs of fibrosis in the liver biopsy. A connection between ECOD and the markers of fibrosis was not found. Further research is necessary to clarify this difference.
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PMID:[7-ethoxycoumarin o-deethylase and fibrosis in chronic liver diseases]. 165 26

Colchicine, which has been used for hundreds of years in the treatment of gout, has found a new use in the treatment of cirrhosis. In the experimental animal, and in vitro, colchicine decreases inflammation, inhibits collagen synthesis and also increases collagen degradation by activating collagenase. Many of the putative beneficial actions of the drug in cirrhosis, as well as its toxic side effects, are due to the fact that it binds to tubulin and thereby disrupts microtubules; however, it is unclear which of these actions, mostly demonstrated in the experimental animal, are present in the doses currently used in man. There have been 4 controlled trials of colchicine in various forms of cirrhosis, three of which have concerned primary biliary cirrhosis. Data are currently available on 146 colchicine-treated patients, of which 92 had primary biliary cirrhosis. Colchicine improves the conventional liver function tests in primary biliary cirrhosis and also reverses the basic defect in hepatic excretory capacity characteristic of this disease. The drug appears to have no significant effect on symptoms, clinical features or liver histology, but in 2 of the 3 primary biliary cirrhosis trials, as in the Mexican study of alcoholic and post-hepatitic cirrhosis, colchicine treatment was associated with improved survival.
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PMID:Colchicine in primary biliary cirrhosis. 177 43

In order to explore the cellular source(s) and the behaviour of the collagenolytic activity previously described in rat liver homogenates, in the reversibility of experimental cirrhosis of the liver, enriched suspensions of hepatocytes and of sinusoidal liver cells were obtained by a procedure which employs low EDTA concentrations and no bacterial collagenase. Cell suspensions were prepared from three different groups of animals: 1) normal controls, 2) rats with CCl4-induced cirrhosis of the liver, and 3) rats with swine serum-induced cirrhosis of the liver. Animals were sacrificed in each group upon completion of treatment and also after 3, 6 and 12 months. In each liver wet weight and collagen concentration were determined, and collagenolytic activity of both enriched cell suspensions was measured separately. In addition, histological studies of liver tissue and ultrastructural examination of cell suspensions were performed by standard procedures. Enriched suspensions of both normal hepatocytes and sinusoidal liver cells display Ca2(+)-dependent collagenolytic activities. Both cell suspensions obtained from each of the two types of cirrhotic livers show normal or slightly increased average levels of collagenase activity at the time of treatment discontinuation, when average liver collagen content ranges from 6 to 10-fold over normal, suggesting that the normal collagenase/collagen ratio is disturbed and that collagenolytic activity is deeply decreased in relation to the actual liver collagen load.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Collagenase of hepatocytes and sinusoidal liver cells in the reversibility of experimental cirrhosis of the liver. 198 May 58

Circulating AC levels as well as antibodies against AC-protein adducts are increased in non-alcoholic liver injury. To identify the adducts, we used rats with CCl4-induced cirrhosis. Liver subcellular fractions were analyzed by immunochemical staining of protein slot blots and of electrophoretically separated proteins, transferred to nitrocellulose, using AC-protein adduct-specific antibodies. One reactive protein of about 200 kD was detected in the liver soluble fraction and in the cytosol of isolated hepatocytes and, to a lesser extent in the liver microsomes of CCl4-treated rats; in control animals, this reactivity was much weaker. The immunopositive AC adduct co-migrated with the beta 1,2 dimer of rat collagen type I; it was sensitive to digestion by a highly purified collagenase and also reacted with anti-rat collagen type I-specific IgG. In addition, comparison of peptides of the CNBr-digested, immunoprecipitated AC adduct with those of rat collagen type I revealed a high degree of similarity. Thus, AC adduct formation occurs in liver injury of non-alcoholic origin, and a target protein appears to be related to collagen type I, most likely the procollagen precursor.
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PMID:Acetaldehyde-collagen adducts in CCl4-induced liver injury in rats. 217 75

Hepatocytes were isolated from thioacetamide (TAA)-induced macronodular cirrhotic rat livers by a collagenase perfusion method. In the content of cellular metabolites, fatty acid uptake and lipid secretion there were no substantial differences compared with cells isolated from micronodular cirrhosis described previously. In contrast to isolated hepatocytes from normal livers those from macronodular cirrhosis had a lowered cellular content of triglycerides, phospholipids and cholesterol but not of cholesterol esters and free fatty acids. In macronodular cirrhosis hepatocytes of hypertrophic type, rich in cell organelles, can be distinguished ultrastructurally from those with signs of atrophy and degeneration. Immediately after isolation many hepatocytes isolated from macronodular cirrhosis showed plasma membrane blebbing. Whereas the blebbing was without recognizable effects on the fine structure of the isolated hepatocytes of the hypertrophic type, in the more atrophic ones some mitochondria were swollen. In addition, morphological analysis of the crude and purified suspensions revealed a partial selection of the hypertrophic cells during the isolation procedure, presumably due to a more labile state of those cells which showed signs of atrophy and degeneration. When stabilized in the suspension medium, however, the hepatocytes maintained complex metabolic functions for at least 2 h. Thus, the method described allows the isolation of parenchymal cells from TAA-induced macronodular cirrhotic livers for studying ultrastructural and biochemical alterations in hyperregenerative experimental liver cirrhosis.
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PMID:Isolation and characterization of parenchymal cells from experimentally induced macronodular rat liver cirrhosis. 254 54


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