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)

Liver cirrhosis is an end stage of several diseases that affect the liver chronically. It is characterized, among other things, by excess collagen deposition, distortion of liver architecture, tissue malfunction and hemodynamic alterations. Many of the complications of cirrhosis may result from excess matrix-deposition. Therefore, prevention of collagen accumulation or removal of collagen deposits could ameliorate the disease. In this article we discuss the pathophysiology of liver fibrosis and we describe various compounds with antiinflammatory and antifibrogenic activity. We discuss their possible mechanism of action and we describe animal and clinical studies in which these compounds have been utilized.
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PMID:Fibrogenesis in cirrhosis. Potential for therapeutic intervention. 164 3

We used immunofluorescence and immunohistochemical PAP methods on 22 paraffin-embedded liver tissue specimens for observation and analysis of the distribution of extracellular matrix (ECM) elements in chronic hepatitis and cirrhosis. Our study revealed that in CLH there was only mild increases of types III, V collagen and fibronectin in spotty necrosis areas. In CPH, types III, V collagen and fibronectin revealed mild to moderate increase in portal area and lobular sinusoid. In CAH, moderate to marked increases of types III, V collagen and fibronectin and mild increase of type IV collagen in portal area, sinusoid lining, piecemeal necrosis and fibroseptum were found. Types I, IV collagen in fibroseptum were also noted. Some periportal hepatocytes showed abundant intracellular fibronectin. In cirrhosis, cases expressed similar finding to CAH except much more type IV collagen deposition. In addition, the basement membrane components including type IV collagen and laminin were found in the "capillarization" of periportal sinusoids in fibrotic liver tissue. In areas of piecemeal necrosis, the hepatocytes, single or assembled in "rosettes", were underlined by linear deposits of laminin and type IV collagen. Our study revealed that, histologically, the ECMs distribution of CAH is similar to that of cirrhosis but could be clearly distinguished from CPH and CLH. The prominent changes of ECMs, especially the basement membrane components, in case of CAH and cirrhosis are consistent with the fact that ECM may play a central role in liver function impairment and fibrogenesis.
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PMID:Extracellular matrix alteration in chronic hepatitis. 165 20

Excessive accumulation of collagen in the extracellular matrix has a crucial role in fibrosis. Thus pharmacological inhibition of collagen deposition is likely to be beneficial for patients suffering from fibrotic disorders such as liver cirrhosis. Prolyl 4-hydroxylase catalyzes the formation of 4-hydroxyproline in collagens and other proteins with collagen-like amino acid sequences by the hydroxylation of proline residues in -X-Pro-Gly- sequences. The reaction products, 4-hydroxyproline residues, serve to stabilize the collagen triple helices under physiological conditions. Conversely, collagen chains that contain no 4-hydroxyproline cannot fold into triple helical molecules that are stable at body temperature. The prolyl 4-hydroxylase reaction therefore seems to be a particularly suitable target for the pharmological regulation of excessive collagen formation. The reaction catalyzed by prolyl 4-hydroxylase requires Fe2+, 2-oxoglutarate, O2 and ascorbate and involves an oxidative decarboxylation of 2-oxoglutarate. The active enzyme is an alpha 2 beta 2 tetramer that consists of two types of inactive monomer and has two catalytic sites. Some parts of the catalytic sites may be built up cooperatively of both the alpha and beta subunits, but the alpha subunit appears to contribute the major part. The beta subunit contains the carboxyl-terminal tetrapeptide sequence -Lys-Asp-Glu-Leu which is essential for the retention of a polypeptide within the lumen of the endoplasmic reticulum. Since the alpha subunit lacks the carboxyl-terminal retention signal, one function of the beta subunit in the prolyl 4-hydroxylase tetramer may be to retain the enzyme within the endoplasmic reticulum.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Prolyl 4-hydroxylase and its role in collagen synthesis. 166 65

The model of biliary cirrhosis by bile duct ligation was further characterized using PIIIP, 7S-collagen as well as standard enzymes in the serum, prolyl 4-hydroxylase and total hydroxyproline in the liver and light microscopical histology. Five weeks after bile duct ligation there was an increase in total collagen content of the liver to 510% of initial values accompanied by an increase of serum-PIIIP (225%) and 7S-collagen (389%). The time-course of this connective tissue proliferation was biphasic with an initial phase of cholestasis and cellular damage followed by rapidly increasing collagen accumulation. The novel prolyl 4-hydroxylase inhibitor HOE 077 reduced the accumulation of collagen in the liver over 6 weeks by 48%. There were no apparent side effects and treated animals showed a tendency towards less functional impairment. The drug's effects, however, were not dose-dependent between daily doses of two times 2 mg/kg and two times 10 mg/kg. These results emphasize the usefulness of the bile duct ligation model for studies of collagen metabolism. They show HOE 077 to be a promising agent for the inhibition of hepatic fibrosis.
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PMID:Fibrosis of the liver in rats induced by bile duct ligation. Effects of inhibition by prolyl 4-hydroxylase. 166 67

Common features of chronic alcoholic liver disease are progressive hypoalbuminemia and liver fibrosis. The molecular mechanisms which account for these effects are still controversial. Therefore, in the present study we evaluated albumin and collagen gene expression in livers of alcohol abusers and patients with viral-induced liver disease. Albumin and pro-alpha 1 (I) collagen mRNA levels were determined in 30 patients who underwent diagnostic liver biopsy. Of 14 alcoholics, 7 had alcoholic hepatitis alone, while the other 7 had cirrhosis plus alcoholic hepatitis. Of 16 non-alcoholic patients with chronic viral infection, 6 had chronic active hepatitis and 10 cirrhosis plus chronic active hepatitis. Total RNA was extracted from a portion of each biopsy, hybridized with a human albumin or collagen cDNA clone and compared to 2 normal surgical specimens which served as controls. The Northern hybridization studies revealed that: despite the presence of inflammation and fibrosis, the albumin mRNA levels of alcoholics were similar to normal controls; these alcoholics had significantly higher levels of albumin mRNA than did patients with similar histological stages of disease due to viral infection; and all the categories of patients had markedly increased procollagen mRNA levels when compared to controls. Given these results it is tempting to speculate that alcohol may actually increase albumin mRNA content in man as it does in animals. Furthermore, the increased procollagen mRNA levels in fibrotic livers suggest that an increase in collagen synthesis may be a significant factor in the pathogenesis of hepatic fibrosis.
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PMID:Albumin and procollagen type I gene regulation in alcohol and viral-induced human liver disease. 167 41

A sandwich ELISA system for detecting vascular basement membrane associated collagen (BAC) was developed. Serum levels of BAC were determined in patients with liver diseases (N = 53), various cancers (N = 65) and other diseases (399). Serum levels of procollagen type III (PIIIP) amino propeptide, type IV collagen.7s domain (7s domain) and other parameters (TP, ALB, GOT, GPT, CHE, gamma-GTP, ALP, LDH, CHE, TG, GLU) were also determined in those patients. In the whole patients, serum concentrations of BAC showed a weak correlation with GOT, GPT, ALB and CHE but not with gamma-GTP and ALP. There was no correlation between BAC and PIIIP or 7s domain. Although serum levels of BAC were elevated in both liver diseases and cancers, the increase in liver diseases was more marked. Markedly increased serum levels of BAC with low levels of CHE were found only in liver cirrhosis and liver cirrhosis plus hepatocellular carcinoma. Increased BAC may reflect capillarization of the liver sinusoid or remodeling of the vascular basement membrane which is observed in the progression of liver fibrosis. Serum BAC is thought to be a promising new marker, different from PIIIP or 7s domain for diagnosing fibrosis state in the organs, particularly in the liver.
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PMID:[Serum level of vascular basement membrane associated collagen by the sandwich ELISA with monoclonal antibodies and its clinical significance in various diseases]. 170 45

Vitronectin (VN), fibronectin (FN) and laminin (LM), which are known to be important glycoproteins in cell attachment, are produced by such liver cells as hepatocytes, Kupffer cells endothelial cells and Ito cells. In this study, the levels of plasma VN, FN and serum LM P1 in patients with chronic hepatitis, liver cirrhosis and hepatocellular carcinoma accompanied with cirrhosis were examined and compared with those in normal subjects. Plasma VN levels in patients with chronic hepatitis, compensated cirrhosis and decompensated cirrhosis were less than that in normal subjects. As hepatic dysfunction deteriorated, plasma VN level decreased in chronic liver diseases. Plasma FN levels in patients with compensated and decompensated cirrhosis were also less than that of patients with chronic hepatitis, which was not significantly different from that of normal subjects. Plasma VN and FN levels in patients with hepatocellular carcinoma were similar to those in patients with compensated cirrhosis. Plasma VN and FN levels in patients with chronic liver diseases including hepatocellular carcinoma showed positive correlations with serum albumin content, cholinesterase activity, and normalized normo test value. On the other hand, serum LM P1 levels in patients with chronic hepatitis, compensated cirrhosis and decompensated cirrhosis were higher than that of normal subjects. As hepatic dysfunction deteriorated, serum LM P1 level increased in chronic liver diseases. Level of serum type IV collagen 7S, which is related to hepatic fibrosis, was similar to that of serum LM P1; serum LM P1 concentration in patients with chronic liver diseases showed a significant positive correlation with that of serum type IV collagen 7S. Immunolocalization of VN in liver tissue from patients with chronic hepatitis and cirrhosis was examined by the method of avidin-biotin-complex staining, and positive reaction was observed in enlarged portal tracts, central veins and fibrous septa. These results suggest that decreased levels of plasma VN and FN and increased level of serum LM P1 in patients with chronic liver diseases are related to hepatic dysfunction, and that changes in the levels of these glycoproteins involved in cell attachment are important in the development of hepatic fibrosis in patients with chronic liver diseases.
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PMID:[Changes in plasma vitronectin, fibronectin, and serum laminin P1 levels and immunohistochemical study of vitronectin in the liver of patients with chronic liver diseases]. 170 42

Serum concentrations of the aminoterminal propeptide of procollagen type III (PIIIP) are elevated in fibrogenic diseases of the liver, but the mechanism of elevation is not fully understood. To investigate the mechanism, we compared serum concentrations of PIIIP with total liver content of mRNA for the pro alpha 1 (III) chain, in rats with carbon tetrachloride (CCl4)-induced liver fibrosis. Adult male rats received CCl4 in mineral oil twice weekly for 8 weeks and were compared with age-matched controls. Serum concentrations of PIIIP were measured by a specific radioimmunoassay; molecular sizes of PIIIP in serum were also determined. Pro alpha 1 (III) mRNA content in the liver was quantitated by RNA slot-blot hybridization and chemical measurement of total hepatic RNA content. Total collagen content of the liver was estimated by hydroxyproline measurement. All CCl4-treated animals had septal fibrosis after 4 weeks, and evidence of cirrhosis (regenerative nodules, ascites) was seen after 7 weeks of treatment. Serum concentrations of PIIIP and pro alpha 1 (III) mRNA content in the liver were correlated well until cirrhosis has established. They increased simultaneously after 3 weeks of treatment, 1 week before any elevation of hepatic hydroxyproline could be detected. After cirrhosis has established, pro alpha 1 (III) mRNA content in the liver decreased markedly, but serum PIIIP levels continued to be elevated. Hepatic hydroxyproline plateaued after 5 weeks. The molecular sizes of serum PIIIP indicate the release of intact native procollagen peptide during the development of cirrhosis. In conclusion, at least in CCl4-induced liver fibrosis in the rats, serum PIIIP levels can be used as a fibrogenic marker for the period progressing to cirrhosis. But the use of the serum PIIIP levels in cirrhosis seems to be limited by factors other than liver fibrogenesis.
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PMID:The serum concentrations of the aminoterminal propeptide of procollagen type III and the hepatic content of mRNA for the alpha 1 chain of procollagen type III in carbon tetrachloride-induced rat liver fibrogenesis. 172 28

In vitro models have shown that metabolites of ethanol (acetaldehyde and lactate) stimulate collagen synthesis, thereby, suggesting that they may be important as fibrogenic mediators. The relevance of these findings for fibrogenesis in the human liver in vivo, however, has not as yet been demonstrated. Serum markers for collagen (PIIINP, using radioimmunoassays employing polyclonal antibodies and Fab-fragments (PIIINP-Fab), respectively) and basement membrane (laminin) metabolism were therefore investigated in 25 alcoholic cirrhotics (Pugh-Score: 6.7 +/- 1.9 S.D.) and in 19 comparable nonalcoholic cirrhotics (Pugh-Score: 6.3 +/- 1.5, n.s.) with only slight evidence for inflammation: GOT 28 +/- 22 vs. 24 +/- 21 U/l; GPT 24 +/- 23 vs. 31 +/- 28 U/l; gamma-globulins 24 +/- 8 vs. 22 +/- 5%, respectively (all n.s.). Severity of the disease was assessed by quantitative liver function tests. Levels of PIIINP, PIIINP-Fab and laminin measured by RIA were 21 +/- 19 micrograms/l, 90 +/- 42 micrograms/l and 2.5 +/- 0.8 U/ml in alcoholic cirrhosis and 10 +/- 6 micrograms/l, 61 +/- 10 micrograms/l and 1.9 +/- 0.4 U/ml in nonalcoholic cirrhosis, respectively (all p less than 0.01). Differences on PIIINP and PIIINP-Fab remained significant even after accurate matching for galactose elimination capacity, aminopyrine breath test and hepatic sorbitol clearance. Laminin levels were higher in alcoholic cirrhosis only after matching for the hepatic sorbitol clearance (p less than 0.01). The higher levels of serum markers for collagen and basement membrane metabolism in alcoholic vs. nonalcoholic patients with cirrhosis at equal severity of the disease and with only minimal signs of inflammation may be the clinical reflection of a specific fibrogenic effect of ethanol metabolites.
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PMID:Higher levels of serum aminoterminal type III procollagen peptide, and laminin in alcoholic than in nonalcoholic cirrhosis of equal severity. 173 19

Liver fat-storing cells (FSC) play an important role in collagen deposition. During the induction of liver cirrhosis, FSC lose their fat droplets, acquire an actin-rich cytoskeleton and transform into myofibroblasts. Myofibroblasts have been associated with increased collagen production in cirrhotic livers. Cultured FSC resemble myofibroblasts. However, it is not known whether regulation of collagen gene expression is similar in FSC obtained from normal or cirrhotic livers. In this communication, we describe the characterization of two fat-storing cell lines, one from normal (NFSC) and one from CCl4-cirrhotic liver (CFSC), obtained after spontaneous immortalization in culture. We studied the effect of serum and various growth factors on cell proliferation. We determined the production of collagen and fibronectin and we analyzed the presence of mRNA transcripts of collagens type I, III, and IV, fibronectin laminin, transforming growth factor-beta and interleukin-6. We found that CFSC have a greater serum-dependency than NFSC. NFSC grow with a mixture of insulin and epidermal growth factor, whereas CFSC proliferate only with platelet-derived growth factor. Although we did not find significant differences in the expression of mRNAs for collagen type I, fibronectin and transforming growth factor-beta, collagen and fibronectin synthesis was increased 2- and 1.5-fold respectively. NFSC contained 1.6- and 2.0-fold more type III collagen and laminin mRNAs, respectively, than CFSC. Neither cell line expressed type IV collagen mRNA. NFSC but not CFSC produced interleukin-6. These results suggest that, except for the lack of transcripts of collagen type IV, both cell lines resemble primary cultures of FSC. However, significant differences in cell proliferation and interleukin-6 production between the two cell lines were found. We suggest that these cell lines could be useful tools to study possible differences in regulation of matrix production by FSC.
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PMID:Characterization of fat-storing cell lines derived from normal and CCl4-cirrhotic livers. Differences in the production of interleukin-6. 175 10


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