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)

Monocytes appear to play a role in immunological abnormalities observed in primary biliary cirrhosis (PBC). Monocytes not only produce fibroproliferative factors, such as IL-1, TNF, and PDGF but also produce superoxide anion which can directly damage tissues, and thus may lead to fibrosis. The aim of this study was to compare the superoxide production in monocytes obtained from 12 control persons, 9 patients with non biliary cirrhosis, 6 untreated PBC patients, 6 patients with gallstones under urso- and chenodeoxycholicacid (Lithofalk) treatment and 32 PBC patients under ursodeoxycholicacid (UDCA) therapy. Monocytes were isolated and the production of superoxide anions with and without phorbol-myristate-acetate (PMA) stimulation was determined. In two occasion, the monocytes from control patients were preincubated with 10, 50, 100 microM UDCA. Unstimulated monocytes from PBC patients under UDCA therapy produce an average 43% more and the PMA stimulated monocytes an average 42% more superoxide than monocytes from the control or from the other cirrhotic patients. The UDCA preincubation did not influence the superoxide production of monocytes obtained from control patients. These findings suggest that the increased activity of monocytes may also play a role in liver damage and fibrosis in PBC.
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PMID:[Comparative study of superoxide production of monocytes in primary biliary cirrhosis]. 747 83

Hemodynamic changes in cirrhosis may be associated with alterations in aortic vascular smooth muscle cell (AVSMC) function. The present study compared the proliferative response to serum and growth factors in cirrhotic and control AVSMC. Serum from cirrhotic rats, cirrhotic cell lysates, and the conditioned medium of cultured cirrhotic AVSMC induced an increase in [3H]thymidine incorporation in control but not in cirrhotic AVSMC. Platelet-derived growth factor-beta (PDGF-BB) induced a greater increase in [3H]thymidine incorporation in cirrhotic than in control cells. [3H]thymidine incorporation induced by cirrhotic conditioned medium was blocked by anti-PDGF antibody. Immunoblot studies showed that the anti-PDGF antibody recognized a 30-kDa protein in the conditioned medium of cirrhotic AVSMC culture, a protein corresponding to PDGF. Binding studies of PDGF-BB indicated a twofold increase in receptor density in cirrhotic AVSMC with no alteration in affinity for PDGF-BB. We conclude that an increased responsiveness of cirrhotic AVSMC to the PDGF could contribute to alterations in AVSMC and muscle cell tone that may play a role in the hemodynamic changes in cirrhosis.
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PMID:Responsiveness to growth factors in aortic vascular smooth muscle cells from rats with cirrhosis. 935 31

This study was designed to investigate the expression and localization of PDGF, bFGF, EGF, and TGF alpha in gastric coronary vein of cirrhotic (n = 30) and non-cirrhotic patients (n = 10) using immunohistochemical technique. The strongly positive immunostaining rate were 93%, 89%, 70% and 68% respectively in cirrhotic patients. The immunostaining was negative in non-cirrhotic patients. The damage to endothelium, hypertrophy and hyperplasia of vascular smooth muscle cells and vascular remodeling were seen in gastric coronary vein of cirrhotic patients. These results suggested that gastric coronary vein could produce growth factor during cirrhosis, the growth factor can act on the vascular function and/or structure via autocrine-paracrine mechanism.
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PMID:Immunohistochemical analysis of growth factor expression and localization in gastric coronary vein of cirrhotic patients. 938 88

Polyenylphosphatidylcholine (PPC), a polyunsaturated phospholipid extract from soy beans, prevents the development of liver cirrhosis in animal models. Its mechanism of action is unknown. Based on the hypothesis that PPC might act by decreasing hepatic stellate cell proliferation, we studied the effect of PPC and its main components, dilinoleoylphosphatidylcholine (DLPC) and palmitoyl-linoleoylphosphatidylcholine (PLPC), on PDGF-induced stellate cell proliferation and intracellular signal transduction. Normal rat hepatic stellate cells in tissue culture were serumstarved, and incubated with 10ng/ml PDGF in the absence or presence of phospholipids. Cell proliferation was measured by 3H-thymidine incorporation. P44MAPK activation was determined by kinase assay, and AP-1 binding by electrophoretic mobility shift assay. PPC (200 ng/ml) significantly inhibited PDGF-induced proliferation (p < 0.05; ANOVA, n = 3) and antagonized PDGF-induced P44MAPK activation and AP-1 binding. This effect was mimicked by DLPC but not by PLPC. Neither DLPC nor PLPC prevented PDGF receptor activation. We conclude that PPC exerts a previously unrecognized effect on mitogen-induced stellate cell proliferation which may be mediated by DLPC. Inhibition of this cascade represents a potential mechanism for the inhibitory effect of PPC on hepatic fibrogenesis.
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PMID:Polyenylphosphatidylcholine inhibits PDGF-induced proliferation in rat hepatic stellate cells. 967 6

By using a selective ROCK inhibitor Y-27632, the role of Rho-ROCK signaling in the function of hepatic stellate cells in culture was studied. Stellate cells maintained the "star-like" configuration of the quiescent stage in the presence of Y-27632, while the expression of smooth muscle alpha-actin and PDGF receptor beta was not affected by the agent. Serum-stimulated migration of the cells was significantly suppressed by Y-27632. The contraction of stellate cells induced by 5 nM endothelin-1 was attenuated by the agent in a dose-dependent manner. Formation of F-actin stress fibers and phosphorylation of myosin light chain was apparently reduced by Y-27632 even under the stimulation with endothelin-1. On the other hand, ex vivo liver perfusion experiment revealed that endothelin-1 (2 nM)-induced increase of portal vein constriction was almost completely inhibited by 20 microM Y-27632 with a concomitant improvement of hepatocyte degeneration. These results suggest that ROCK is one of the key regulators of stellate cell motility and that the clinical application of ROCK inhibitors such as Y-27632 should be considered in the reduction of portal hypertension in liver fibrosis and cirrhosis.
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PMID:ROCK inhibitor Y-27632 attenuates stellate cell contraction and portal pressure increase induced by endothelin-1. 1060 Apr 96

Cytokines are a group of proteins with autocrine, paracrine and endocrine activities which provide communication among hepatic cells and other cells and tissues of the man. Active in minute quantities, the cytokines activate and regulate homeostasis and cellular repair through effects on cell growth, differentiation and receptor expression and cell-mediated immunity. Cytokines--IL-1, IL-2, IL-6, IL-8 IL-10, IL-12, TNF-alfa, PDGF and others, modulate liver metabolism in health and disease, physiological and pathologic liver functions and the evolution of liver inflammation and injury to hepatic fibrosis and liver cirrhosis. Data concerning the use of a recombinant form of Interleukin-10 and Interleukin-12 in the treatment of chronic liver disease (chronic viral hepatitis, fibrosis, cirrhosis, alcoholic liver disease) and cell-mediated immunity regulation are widely discussed in the review.
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PMID:[Cytokines and the liver in health and disease]. 1119 92

Platelet-derived growth factor (PDGF) overactivity has been implicated in atherosclerosis and several fibrotic conditions including lung and kidney fibrosis, liver cirrhosis and myelofibrosis. Low oxygen tension (hypoxia) is a known stimulus for transcriptional induction of PDGF ligand and receptor genes in different tissues. We studied the expression and localization of PDGF-A, PDGF-B, and PDGF receptor (PDGFR)-alpha and -beta subunits in adult rat isolated corpus cavernosum (CC) under generalized transient hypoxia (pO(2) 10%) in comparison with normoxic conditions. Semi-quantitative RT-PCR analysis of mRNA extracted from rat penis showed higher amounts of PDGF-A, PDGF-B and PDGFR-beta mRNA transcripts in hypoxic versus normoxic animals. The immunohistochemical analysis showed that the localization of PDGF subunits and PDGFR-beta was confined to the cytoplasm of the perivascular smooth muscle cells, endothelium and trabecular fibroblasts. Our findings indicate that transient low oxygen tension induces PDGF overexpression in rat CC, which in the long term may lead to an increase of connective tissue production. We suggest that a local impairment of the PDGF/PDGFR system may contribute to CC fibrosis, which is an established cause of erectile dysfunction in man.
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PMID:Platelet-derived growth factor (PDGF) and PDGF receptors in rat corpus cavernosum: changes in expression after transient in vivo hypoxia. 1147 35

Hepatic stellate cells (HSCs) and transdifferentiated myofibroblasts are the principal producers of excessive extracellular matrix in liver fibrosis and cirrhosis. Activation of HSC is regulated by several cytokines and growth factors, including platelet-derived growth factor B-chain (PDGF-B), a potent mitogen for HSC, and overexpressed during hepatic fibrogenesis. Previous studies showed that MAPK and phosphatidylinositol 3' kinase are key signaling pathways involved in PDGF-induced stimulation of HSC. Based on the involvement of PDGF-B in fibrogenesis, reducing ligand stimulation of proliferative cytokine- or growth factor receptors interfering with receptor signaling therefore presents an interesting strategy for hepatic fibrosis prevention or interruption. We therefore generated an adenoviral vector serotype 5 (Ad5) expressing an antisense mRNA of the PDGF B-chain (Ad5-CMV-asPDGF) for application in an experimentally induced liver fibrogenesis model. The transgene clearly showed the ability to down-regulate endogenous PDGF B-chain and PDGFRbeta mRNA in culture-activated HSC and rat livers. The asPDGF mRNA also attenuates experimental liver fibrogenesis indicated by reduced levels of alpha-SMA and collagen type I expression.
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PMID:Antisense strategy against PDGF B-chain proves effective in preventing experimental liver fibrogenesis. 1535 92

Inhibition of hepatic stellate cell activation is an important clinical aspect for the control of liver inflammation, fibrosis and cirrhosis. S-adenosyl-L-methionine (SAM), an intermediate product of L-methionine metabolism, is a precursor of glutathione and an endogenous methyl donor. Although the hepato-protective action of SAM has been reported in several animal models, the effect of SAM on the function of hepatic stellate cells has not been elucidated. Using a primary-culture model of hepatic stellate cells, we found that SAM blunts the activation process as indicated by the suppression of expression of collagen alpha1(I) and smooth muscle alpha-actin. SAM also hampers the DNA synthesis of hepatic stellate cells stimulated with a dimer of platelet-derived growth factor-B via the inhibition of phosphorylation of PDGF receptor-beta and down-stream signaling pathways. SAM additionally inhibits the contraction of hepatic stellate cells by disturbing the formation of F-actin stress fibers and phosphorylated myosin light chains. Thus, SAM regulates the activation of hepatic stellate cells and may clinically contribute to therapy targeted at human liver fibrosis.
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PMID:Effect of S-adenosyl-L-methionine on the activation, proliferation and contraction of hepatic stellate cells. 1571 26

Chronic ethanol-induced liver injury follows a typical progression from its earliest stage of steatosis to more advanced injury, characterized by the development of inflammation, hepatocyte necrosis/apoptosis, fibrosis and finally cirrhosis. Kupffer cells, the resident macrophage in the liver, play a critical role in the progression of liver injury. Increased exposure of Kupffer cells to lipopolysaccharide (LPS) during chronic ethanol exposure leads to the production of a number of inflammatory mediators, including tumor necrosis factor alpha (TNF-alpha). Recent evidence indicates that in addition to increased exposure to LPS, Kupffer cells also develop an enhanced sensitivity to LPS after chronic ethanol feeding. We have recently identified early growth response-1 (Egr-1), an immediate-early gene transcription factor, as an important contributor to increased LPS-stimulated TNF-alpha secretion by Kupffer cells after chronic ethanol exposure. In other models of tissue injury, such as ischemia-reperfusion in the lung, Egr-1 acts as a coordinator of the complex response to stress. Here we review the literature regarding the role of EGR-1 in regulation of a number of genes implicated in each of the stages of chronic ethanol-induced liver injury. In addition to the critical role of Egr-1 in generating maximal LPS-stimulated TNF-alpha expression, Egr-1 also controls the expression of a number of inflammatory mediators, including intercellular adhesion molecule (ICAM)-1, monocyte chemotactic protein (MCP)-1 and macrophage inflammatory protein (MIP)-2, as well as genes contributing to fibrosis, such as transforming growth factor (TFG)-beta1, platelet-derived growth factor PDGF-A chain and fibroblast growth factor (FGF). Understanding the contribution of Egr-1 to the expression of genes involved in the development of chronic ethanol-induced liver injury may lead to the development of improved therapies designed to prevent and/or reverse alcohol-induced liver injury.
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PMID:Ethanol-induced liver injury: potential roles for egr-1. 1634


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