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)

Increased acetaldehyde levels have been found in non-alcoholic liver diseases and an acetaldehyde-collagen adduct has been reported in rats with CCl4-induced cirrhosis. In cytosol and microsomes of rats with cirrhosis produced by N-nitrosodimethylamine, a similar acetaldehyde-protein adduct of approximately 200 kD was recognized by rabbit IgG raised against either an in vitro produced hemocyanin-acetaldehyde adduct or an in vivo occurring P4502E1-acetaldehyde adduct isolated from alcohol-fed rats, as well as by anti-rat collagen (I) IgG. Its immune complexes contained 3 proteins that reacted with the anti-collagen IgG and were digested by collagenase: 2 proteins with molecular weights similar to procollagens alpha 1 and alpha 2, and a beta 1,2(I)-like protein which was readily produced by in vitro modification of cytosol with acetaldehyde.
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PMID:Acetaldehyde-collagen adducts in N-nitrosodimethylamine-induced liver cirrhosis in rats. 846 25

Some recent proposals in management of alcoholic liver disease are discussed focusing on early diagnosis and treatment of alcohol abuse itself, alcoholic hepatitis early mortality, clinical meaning of nutritional therapy, serological approach and treatment of hepatic fibrosis, and problems in liver transplantation for end stage alcoholic liver cirrhosis. CAGE or similar systematized brief questionnaires, and desialylated transferrin/total transferrin ratio as serological marker, seems to be interesting contributions to "hidden" alcohol abuse diagnosis and abstinence control while psycho-social support and voluntary incorporation to self-aid groups are the best weapons to reach persistent abstinence. Corticosteroids seems to improve survival in a selected group of patients with severe alcoholic hepatitis, specially in those presenting encephalopathy but free of GI bleeding, decompensated diabetes, active infections, pancreatitis, and other contraindications or adverse effects of these drugs. Relationship between direct toxicity and nutritional deficiencies in pathogenesis of alcoholic liver injury are not clear enough, but malnutrition is generally present in patients requiring hospitalization, and related to clinical severity; oral, enteral or parenteral nutritional supplementation in this order of preference according to patients condition, associated or not with steroid anabolics, are useful in cases with moderate to severe alcoholic hepatitis or decompensated cirrhosis to eliminate the catabolic state, reaching a better nitrogen balance and liver function tests, without special adverse effects. A special role on liver regeneration is discussed. Antioxidants and supernutrients are special "modern" aspects of nutritional therapy in alcoholic liver disease generally related to the MEOS activation in chronic alcoholism, the excessive production of free radicals, and the depletion of glutathione, membrane phospholipids (specially phosphatidycholine), and vitamin A, E, and C. Natural supplements as soybean polyunsaturated lecithin, with high concentration of phosphatidycholine, or oral supplementation with natural metabolic products depleted from the liver of chronic heavy drinkers, such SAMe, have an interesting rationale based on experimental and clinical findings besides availability and costs. Carotenoids and tocopherols supplementation seems to be an useful tool, but are limited in the case of vitamin A because its special toxicity in chronic alcoholism. Serological markers of metabolism of liver connective tissue are clearly involved in fibrogenesis process and other inflammatory connected events; standardization of laboratory methods surely will result in new possibilities of non-invasive valuation of liver injury, evolution and therapeutic response; special histological damage such as sinusoidal "cappilarization" (type i.v. collagen and laminin), endothelial sinusoidal cell function (seric hyaluronate), or collagenase activity (TIMP-1 or tissue inhibitor of metalloproteinases-1) seems to be valuable by these new technologies.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:[New suggestions for the management of alcoholic liver diseases]. 852 63

We evaluated the mechanism of increased serum concentrations of the 7S fragment of the N-terminal domain of type IV collagen (7S collagen) in chronic liver disease. We measured the concentrations of hepatic-free and deposited 7S collagens after extraction with Tris-HCl buffer and bacterial collagenase, then compared them with the serum levels in 8 normal controls and 48 patients with chronic liver disease. The hepatic 7S collagen levels extracted with Tris-HCl buffer and collagenase accounted for 7% and 93%, respectively, of the total 7S collagen levels in normal controls. Both hepatic 7S collagen levels as well as serum levels increased in accordance with the progress of liver disease. Serum levels of 7S collagen showed a closer correlation with the hepatic 7S collagen levels extracted with Tris-HCl buffer (r = .822), compared with those extracted with collagenase (r = .382). On the other hand, the histological degrees of liver fibrosis were highly correlated with the hepatic collagenase-extracted 7S collagen levels (r = .822), compared with serum and the hepatic Tris-HCl buffer-extracted levels (r = .478 and r = .537, respectively). Although there was no difference in serum and hepatic 7S collagen levels between B and C viral patients, the serum and hepatic Tris-HCl buffer-extracted 7S collagen levels were higher in patients with alcoholic cirrhosis than patients with viral cirrhosis. However, the hepatic collagenase-extracted levels were similar in both groups. Gel filtration demonstrated that the serum and hepatic Tris-HCl buffer-extracted 7S collagens were mainly eluted in the macromolecular 7S collagen-reactive fraction in cirrhosis, whereas the hepatic collagenase-extracted 7S collagen was eluted in the authentic 7S collagen-reactive fraction. The results suggest that serum 7S collagen levels are not a particularly reliable measure of hepatic fibrosis but reflect the enhanced metabolism, especially synthesis of type IV collagen in the liver.
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PMID:Relationship between serum and hepatic 7S fragments of type IV collagen in chronic liver disease. 862 Nov 48

Heptic fibrosis/cirrhosis is a common hepatic disease characterized by the hyper-accumulation of connective tissue components, and hepatic necrosis. Chronic alcohol ingestion, viral infection, and metabolic disorders are contributing factors and there has been no effective treatment. Hepatocyte growth factor (HGF), originally identified as a potent mitogen for mature hepatocytes, is a long-sought hepatotrophic factor for liver regeneration. Administration of human recombinant HGF into rats with hepatic fibrosis/cirrhosis caused by dimethylnitrosamine (DMN) elicited mitogenic action for hepatocytes, stimulated hepatic collagenase activity, and prevented the onset and progression of hepatic fibrosis/cirrhosis. Accumulation of fibrous tissue components in the liver due to DMN-treatment were markedly decreased in HGF-injected rats. Moreover, HGF completely abrogated death caused by severe hepatic cirrhosis and dysfunction. We postulate that HGF may prove to be an effective treatment for human liver fibrosis/cirrhosis and for chronic hepatic failure.
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PMID:Hepatocyte growth factor suppresses the onset of liver cirrhosis and abrogates lethal hepatic dysfunction in rats. 869 Jul 30

Alcohol affects the liver through metabolic disturbances associated with its oxidation. Redox changes produced by the hepatic alcohol dehydrogenase pathway affect lipid, carbohydrate and protein metabolism. Ethanol is also oxidized in liver microsomes by the ethanol-inducible cytochrome P4502E1, resulting in ethanol tolerance and selective hepatic perivenular damage. Furthermore, P4502E1 activates various xenobiotics, explaining the increased susceptibility of the heavy drinker to the toxicity of anesthetics, commonly used medications (i.e. isoniazid), analgesics (i.e. acetaminophen), and chemical carcinogens. Induction of microsomal enzymes also contributes to vitamin A depletion, enhances its hepatotoxicity and results in increased acetaldehyde generation from ethanol, with formation of protein adducts, glutathione depletion, free-radical-mediated toxicity, and lipid peroxidation. Chronic ethanol consumption strikingly enhances the number of hepatic collagen-producing activated lipocytes. Both in vivo (in our baboon model of alcoholic cirrhosis) and in vitro (in cultured myofibroblasts and activated lipocytes) ethanol and/or its metabolite acetaldehyde increase collagen accumulation and mRNA for collagen. Gender differences are related, in part, to lower gastric ADH activity (with consequent reduction of first pass ethanol metabolism) in young women, decreased hepatic fatty acid binding protein and increased free-fatty acid levels as well as lesser omega-hydroxylation, all of which result in increased vulnerability to ethanol. Elucidation of the biochemical effects of ethanol are now resulting in improved therapy: in baboons, S-adenosyl-L-methionine attenuates the ethanol-induced glutathione depletion and associated mitochondrial lesions, and polyenylphosphatidylcholine opposes the ethanol-induced hepatic phospholipid depletion, the decrease in phosphatidylethanolamine methyltransferase activity and the activation of hepatic lipocytes, with full prevention of ethanol-induced septal fibrosis and cirrhosis; its dilinoleoyl species also increases collagenase activity in lipocytes. The efficacy of this compound in man is now being studied in randomized multicenter clinical trials.
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PMID:Susceptibility to alcohol-related liver injury. 897 51

Alcohol-induced tissue damage results from associated nutritional deficiencies as well as some direct toxic effects, which have now been linked to the metabolism of ethanol. The main pathway involves liver alcohol dehydrogenase which catalyzes the oxidation of ethanol to acetaldehyde, with a shift to a more reduced state, and results in metabolic disturbances, such as hyperlactacidemia, acidosis, hyperglycemia, hyperuricemia and fatty liver. More severe toxic manifestations are produced by an accessory pathway, the microsomal ethanol oxidizing system involving an ethanol-inducible cytochrome P450 (2E1). After chronic ethanol consumption, there is a 4- to 10-fold induction of 2E1, associated not only with increased acetaldehyde generation but also with production of oxygen radicals that promote lipid peroxidation. Most importantly, 2E1 activates many xenobiotics to toxic metabolites. These include solvents commonly used in industry, anaesthetic agents, medications such as isoniazid, over the counter analgesics (acetaminophen), illicit drugs (cocaine), chemical carcinogens, and even vitamin A and its precursor beta-carotene. Furthermore, enhanced microsomal degradation of retinoids (together with increased hepatic mobilization) promotes their depletion and associated pathology. Induction of 2E1 also yields increased acetaldehyde generation, with formation of protein adducts, resulting in antibody production, enzyme inactivation, decreased DNA repair, impaired utilization of oxygen, glutathione depletion, free radical-mediated toxicity, lipid peroxidation, and increased collagen synthesis. New therapies include adenosyl-L-methionine which, in baboons, replenishes glutathione, and attenuates mitochondrial lesions. In addition, polyenylphosphatidylcholine (PPC) fully prevents ethanol-induced septal fibrosis and cirrhosis, opposes ethanol-induced hepatic phospholipid depletion, decreased phosphatidylethanolamine methyltransferase activity and activation of hepatic lipocytes, whereas its dilinoleoyl species increases collagenase activity. Current clinical trials with PPC are targeted on susceptible populations, namely heavy drinkers at precirrhotic stages.
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PMID:Ethanol metabolism, cirrhosis and alcoholism. 902 26

Activated hepatic stellate cells (HSC) participate in matrix remodeling and deposition in liver fibrosis. The present study demonstrates that interleukin (IL)-10 is expressed by HSC upon activation in vitro or in vivo and that autocrine effects of this cytokine include inhibition of collagen production. Culture activation of HSC caused a distinct increase in IL-10 mRNA level compared with freshly isolated quiescent HSC. Treatment of cultured HSC with tumor necrosis factor-alpha, transforming growth factor-beta, or lipopolysaccharide further increased IL-10 mRNA by 2-fold and resulted in the release of IL-10 protein into the medium. HSC isolated from rats after bile duct ligation (BDL) showed prominent increases in IL-10 mRNA (x 100) and protein (x 30) levels at 7 days after BDL, but such induction disappeared in advanced liver fibrosis (19 days after BDL). IL-10 expression correlated positively with mRNA expression of interstitial collagenase and inversely with that of alpha1(I) collagen. Addition of anti-IL-10 IgG to cultured HSC caused enhanced collagen production under a basal or stimulated condition with TGF-beta, tumor necrosis factor-alpha, or lipopolysaccharide. These effects were associated with increased alpha1(I) collagen mRNA and reciprocally reduced collagenase mRNA levels. Co-transfection of HSC with an IL-10 expression vector and collagen reporter genes showed a 40% inhibition of alpha1(I) collagen promoter activity. These results demonstrate that activation of HSC causes enhanced autocrine expression of IL-10 which possesses a negative autoregulatory effect on HSC collagen production mediated at least in part by alpha1(I) collagen transcriptional inhibition and stimulation of collagenase expression. These findings, along with the demonstrated early induction of HSC IL-10 expression and its late disappearance during biliary liver fibrosis, suggest its in vivo role in matrix remodeling and a possibility that failure for HSC to sustain IL-10 expression underlies pathologic progression to liver cirrhosis.
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PMID:Expression of interleukin-10 by in vitro and in vivo activated hepatic stellate cells. 941 80

The prevention of cirrhosis in alcohol-fed baboons by the administration of a soybean extract-43% to 50% of which was dilinoleoyl-phosphatidylcholine (DLPC) and 24% of which was 1,palmitoyl 2,linoleoyl-phosphatidylcholine (PLPC)-was associated with a significant reduction in the number of stellate cells transformed to myofibroblast-like cells. To study whether these two major phospholipids affect the similar transformation that occurs by culturing stellate cells on uncoated plastic, we assessed their effects on proliferation (by (methyl-3H)-thymidine incorporation into DNA), expression of alpha-smooth muscle actin and type I procollagen (by densitometry of Western blots), and collagen synthesis (by incorporation of tritiated proline into collagenase-digestible proteins). These manifestations of stellate cell activation were decreased by 10 micromol/L DLPC but not by 10 micromol/L PLPC when compared with controls incubated either with 17 mmol/L ethanol (used as solvent for the phospholipids) or without addition. These agents did not affect cell viability, contamination with other cells, or the capacity of stellate cells to synthesize protein. Thus DLPC specifically decreases the in vitro activation of stellate cells, as judged by the decreases in proliferative activity, alpha-smooth muscle actin and procollagen I expressions, and collagen synthesis, whereas PLPC did not show such effects. alpha-Procollagen (type I) mRNA was not affected by DLPC, suggesting a post-translational effect. The reduction in the activation of hepatic stellate cells by DLPC may be responsible for, or at least contribute to, the prevention of fibrosis by the polyenylphosphatidylcholine mixture administered in vivo.
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PMID:Dilinoleoylphosphatidylcholine decreases hepatic stellate cell activation. 1021 64

Glomerular IgA deposits were eluted from biopsied kidney tissues of patients with IgA nephritis and the antibody specificity was analyzed. The IgA was successfully eluted with combined use of citrate buffer and collagenase. The elution procedure did not attenuate antibody activity which was confirmed by the preliminary experiment that mouse IgA monoclonal anti-DNP antibody similarly treated did not cause any decline of antigen-binding ability. Because of the limited amounts ranging from 80-800 ng/ml, the eluted IgA did not react with respective lysates of the kidney tissues from which the IgA had derived. Moreover, kidney tissues from 9 biopsies yielded 5 micrograms/ml of IgA, when mixed together as source of IgA; nevertheless, the eluted IgA did not react with the kidney lysates, either. The eluted IgA, however, did react with several bacterial antigens, among which the 34-kDa antigen from Haemophilus influenzae (34-kDa H. influenzae) was most clearly detected with IgA eluted from pooled 10 kidney samples of IgA nephritis, which was confirming by Western blot analysis. The reactivity of the eluted IgA with the 34-kDa H. influenzae antigen was seen in 3/5 of IgA nephritis and 3/9 of non IgA nephritis patients with glomerular IgA deposits, respectively. The reactivity of serum IgA with the bacterial antigen was also investigated, which revealed that the serum IgA reacted with the 34-kDa antigen in 2/12 of IgA nephritis, 4/10 of liver cirrhosis patients and 3/10 of healthy control individuals, respectively. The surerum IgA from the IgA nephritis patients appeared to react with 34-kDa antigen more intensively than did healthy control IgAs. These results suggest that the 34-kDa H. influenzae plays an important role in the pathogenesis of at least certain IgA nephritis cases.
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PMID:[Isolation of glomerular IgA deposits from biopsied kidney tissues of patients with IgA nephritis and analysis of the antibody specificity of IgA]. 1042 65

Chronic liver disease evaluation is a very complicated process requiring complex assessment of numerous liver functions. In addition to standard methods of investigation we perform biotransformation liver tests for evaluation of microsome enzyme system. Markers of fibrogenesis represent modern noninvasive tests for fibrotic liver process detection in different diseases. The key role in the process of fibrogenesis have the adipose liver cells (ITO cells) producing collagen I, III, IV and lamilin. These cells may be transformed into myofibroblasts-like cells under specific conditions. Kupffer cells and monocytes produce substances stimulating the proliferation and transformation of liver ITO cells as also proteoglycans and hyaluronic acid synthesis. Mediators of this fibrogenetic activity are platelet derived growth factor (PDGF), transforming growth factors alpha and beta, lymphokines and monokines released by T-lymphocytes and macrophages, interleukin 1-alpha and interferon-tau. Acetaldehyde and its metabolites are important stimulators of collagen production by liver fibroblasts. The most often used markers of hepatic fibrogenesis are the following: procollagen III peptide, procollagen IV. type (one of its end carboxypeptide chains is determined-either with 7s collagen or NC1), hyaluronic acid, fibronectin, tenascine and unduline. As the most sensitive markers of fibrinogenesis are considered: hyaluronic acid, laminine, procollagen IV. type. Less often used are enzymes participating in collagen synthesis: prolyl-4-hydroxylase,lysyl-hydroxylase, galactosyl-hydroxylysyl-glucosyl-transferase, monoaminooxidase and N-acetyl-beta-D-glucoseaminidase. Breakdown of collagen is a multienzymatic process, catalysed by collagenases and other proteolytic enzymes. Decreased activity of collagenase is a supporting factor of cirrhosis development. Cirrhosis may be connected also with the levels of inhibitors such as e.g. serum/tissue? inhibitor of metalloproteinase. Biochemical markers of fibrogenesis are useful in regular monitoring of disease development and treatment effectivness and should be an inseparable part of progression assessment in all chronic hepatopathies. (Fig. 3, Ref. 49.)
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PMID:[Biochemical markers of fibrogenesis in liver diseases]. 1049 95


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