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)

Hepatic collagen synthesis was studied during progressive fibrosis induced by carbon tetrachloride in male Sprague-Dawley rats by determination of prolyl hydroxylase activity and hydrocyproline levels along with morphological assessment of fibrosis. Cirrhosis was present after approximately 4 weeks treatment. Prolyl hydroxylase activity was increased significantly before fibrosis was apparent histologically or by hydroxyproline levels. The significance of this finding is discussed.
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PMID:Hepatic prolyl hydroxylase activity in experimental cirrhosis. 17 70

Prolyl hydroxylase activity was determined in liver biopsy samples obtained from 10 patients. The liver prolyl hydroxylase values in patients with active hepatitis distribute into two numerical populations based on the extent of elevation over control. The first of these groups includes those with enzyme levels elevated approximately 2.5-fold over normal. Included in this group are patients with active (but nonagrressive) hepatitis and patients where advanced portal fibrosis is already established. The second group where prolyl hydroxylase is elevated approximately nine-fold is comprised of two patients with advanced clinical symptoms of active alcoholic hepatitis with evidence of aggressive cirrhosis but with only early minimal evidence of existing fibrosis.
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PMID:Prolyl hydroxylase activity in normal and diseased human liver. 17 74

100 patients were laparoscopied, liver tissue specimens taken from atypically altered areas. Prolyl hydroxylase was determined in the specimen, in parallel tissue was examined by light microscope. 8 groups of patients could be differentiated: Patients 1. with active, 2, with inactive cirrhosis, 3. with fatty infiltrations, 4. with fatty infiltration and mesenchymal reaction, 5. with aggressive, 6. with persistent, 7. with reactive hepatitis, 8. patients without histological changes. In the case of connective tissue increase in the liver prolyl hydroxylase activities were statistically significant above normal. In addition, there was a statistically significant difference between the enzyme activities of each group. A correlation could be found between prolyl hydroxylase activity and morphologically estimated connective tissue formation, but not the serum enzyme activities usually determined in liver diseases. Therefore, could be concluded that prolyl hydroxylase activity is an index of actual collagen biosynthesis in chronic liver diseases.
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PMID:[Prolyl hydroxylase activity in liver specimens in chronic liver diseases (author's transl)]. 21 Mar 65

Hepatic prolyl hydroxylase activity and collagen synthesis were measured in patients with alcoholic liver disease to determine the feasibility of using the enzyme prolyl hydroxylase as a marker of hepatic fibrogenesis. Alcoholic patients with liver histopathology consistent with normal, steatosis, alcoholic hepatitis, early cirrhosis, or advanced cirrhosis were analysed for liver prolyl hydroxylase activity and in vitro collagen synthesis. Prolyl hydroxylase activity and the rate of in vitro collagen synthesis were correlated when these parameters were measured in samples of the same liver biopsy. Mean prolyl hydroxylase activity was significantly raised in all groups of alcoholic patients with alcoholic liver disease, except those with steatosis, when compared with alcoholic patients with normal morphology. Alcoholic patients with early cirrhosis had enzyme activity (mean +/- SE: 1.367 +/-0.162 mU/mg protein) significantly raised over all other groups. Mean enzyme activity was less raised (0.985 +/- 0.097 mU/mg protein) in patients with advanced cirrhosis. The percentage of collagen synthesis in patients with early or advanced cirrhosis was also raised compared with alcoholic patients with normal morphology. Prolyl hydroxylase activity and the rate of collagen synthesis are significantly correlated (r=0.62). These findings suggest that hepatic prolyl hydroxylase activity is a useful indicator of hepatic fibrogenesis and its measurement on available liver biopsy tissue should be a potent diagnostic tool reflecting active fibrogenesis and predicting progression of alcoholic liverdisease.
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PMID:Hepatic prolyl hydroxylase and collagen synthesis in patients with alcoholic liver disease. 23 Jan 28

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 activity of prolyl hydroxylase was measured in liver tissue obtained from a small series of patients with a variety of liver disease. Enzyme levels were marginally elevated in patients with fatty liver and viral hepatitis, conditions not normally associated with progressive fibrosis. In some patients with alcoholic hepatitis and in all patients with cirrhosis and chronic active hepatitis, there was a marked increase in enzyme activity. Patients with conditions characterised by high liver prolyl hydroxylase levels showed histological evidence of extensive hepatic fibrosis and also significant increases in the serum values of glutamate dehydrogenase and gamma-glutamyl-transpeptidase. Prolyl hydroxylase activity was not detected in serum.
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PMID:Hepatic prolyl hydroxylase activity in human liver disease. 625 37