Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0239946 (liver fibrosis)
 8,268 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Liver fibrosis is characterized by activation of hepatic stellate cells, which are then involved in synthesis of matrix proteins and in regulating matrix degradation. In the acute phases of liver injury and as liver fibrosis progresses, there is increased expression of matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs). Among the changes described, striking features include increased expression of gelatinase A (MMP-2) and membrane type 1-MMP (MT(1)-MMP; MMP-14) as well as TIMP-1 and TIMP-2. These molecules and other family members are involved in regulating degradation of both normal and fibrotic liver matrix. This article outlines recent progress in this field and discusses the mechanisms by which MMPs and TIMPs may contribute to the progression and regression of liver fibrosis. Recently described properties of MMPs and TIMPs of relevance to the pathogenesis of liver fibrosis are outlined. The proposal that regression of liver fibrosis is mediated by decreased expression of TIMPs and involves degradation of fibrillar collagens by a combination of MT(1)-MMP and gelatinase A, in addition to interstitial collagenase, is explored.
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PMID:Fibrogenesis II. Metalloproteinases and their inhibitors in liver fibrosis. 1091 30

Following liver injury, hepatic stellate cells (HSCs) become activated and express a combination of matrix metalloproteinases (MMPs) and their specific tissue inhibitors (TIMPs). In the early phases of liver injury (and primary cell culture), HSCs transiently express MMP-3, MMP-13, and uroplasminogen activator (uPA) and exhibit a matrix-degrading phenotype. In the later stages of liver injury and HSC activation, the pattern changes and the cells express a combination of MMPs that have the ability to degrade normal liver matrix, while inhibiting degradation of the fibrillar collagens that accumulate in liver fibrosis. This pattern is characterized by the combination of pro-MMP-2 and membrane type 1 (MT1)-MMP expression, which drive pericellular generation of active MMP-2 and local degradation of normal liver matrix. In addition there is a marked increase in expression of TIMP-1 leading to a more global inhibition of degradation of fibrillar liver collagens by interstitial collagenases (MMP-1/MMP-13). These pathways play a significant role in the progression of liver fibrosis. Following cessation of liver injury, the pattern reverses and TIMP-1 in particular is rapidly downregulated. This phase is characterized by increasing activity of collagenases, degradation of liver matrix, and regression of liver fibrosis.
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PMID:Extracellular matrix degradation and the role of hepatic stellate cells. 1158 66

Hepatic fibrosis is the hallmark of Schistosoma mansoni infection and often results in portal hypertension and bleeding from esophageal varices. The fibrotic process is highly dependent on type 2 cytokines, yet their role in the regulation of extracellular matrix remodeling genes remains largely unknown. Here, we examined the expression of matrix metalloproteases (MMP) -2, -3, -9, -12, and -13 and their inhibitors, tissue inhibitor of metalloproteases (TIMP) -1, -2, and -3, in the livers of infected mice and correlated their expression profiles with fibrosis and type 2 cytokine production. Expression of MMP-2, -3, -9, -12, and -13 and of TIMP-1 and -2 mRNA rapidly increased at the onset of egg laying in infected mice, while TIMP-3 was unchanged. Because TIMP are presumed to be important regulators of the extracellular matrix, and their expression correlated with the development of fibrosis, we studied their role in fibrogenesis by infecting TIMP-1- and TIMP-2-deficient mice. Strikingly, our data revealed no role for TIMP-1 or -2 in the fibrotic pathology induced by S. mansoni eggs. Because of these findings, we infected IL-10/IFN-gamma-deficient mice that develop an exaggerated fibrotic response to determine whether changes in type 2 cytokine dominance influence the pattern of MMP and TIMP expression. Fibrosis and type 2 cytokine production correlated with increased MMP-2/MMP-9 vs TIMP-1/TIMP-2 expression. These data, in addition to our knockout studies, demonstrate that TIMP-1/TIMP-2 play no essential role in fibrogenesis in schistosomiasis. Indeed, our findings suggest that inhibiting profibrotic cytokines or specific MMP may be a more effective strategy to ameliorate fibrotic pathology.
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PMID:Regulation of hepatic fibrosis and extracellular matrix genes by the th response: new insight into the role of tissue inhibitors of matrix metalloproteinases. 1173 22

AIM:To investigate clinic effects of Fuzheng Huayu 319 recipe (319 recipe) on liver fibrosis in chronic hepatitis B.METHODS:Ninety-five patients with chronic hepatitis B were divide into the treated (63 cases) and control (32 cases) group, and orally administrated with 0.5g 319 capsule or 0.5g Dahuang Zhachong pill tid for 3 months, respectively. The liver functions and serological fibrotic markers were observed before and after treatment, 12 cases in the treated group were examined with liver biopsy.RESULTS:Three hundreds nineteen recipe could remarkably decreased serum ALT level and total bilirubin and significantly improve serum albumin and A/G ratio. Its effects were better than Dahuang Zhachong pill. Before treatment, patients'serum monamine oxidase activities, tissue inhibitor of metalloproteinase (TIMP)-1, procollagen type and laminin were all higher than those of health peoples. These levels decreased remarkably after treatment,and urine hydroxyproline level increased significantly (P < 0.001-0.05). Compared with the control, the improvement in treated group was better than that in the control except TIMP-1. According to the scoring system for staging of chronic hepatitis, the fibrotic extents of 7 cases among 12 cases examined by liver biopsy decreased remarkably (1 case decreased by 3 scores, 5 by 2 scores, 1 by 1 score).CONCLUSION:Fuzheng Huayu 319 recipe had good therapeutic effects on chronic hepatitis B, it could reverse the development of liver fibross to some extent. In general its effects were better than that of Dahuang Zhachong pill.
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PMID:Effects of Fuzheng Huayu 319 recipe on liver fibrosis in chronic hepatitis B. 1181 18

A number of circulating breakdown products of collagen or other components of extracellular matrix, matrix degrading metalloproteinases (MMPs) and their tissue inhibitors (TIMPs) have been proposed as markers of hepatic fibrosis. However, the published results lack consistency. Since many of the patients with fibrosis studied were alcoholics, the question was raised whether recent alcohol consumption may affect the results obtained. Using sandwich-type assays of radioimmunoassay technology with corresponding antibodies, we studied eight markers of liver fibrosis: laminin, tenascin, undulin, TIMP-1, collagen VI, procollagen type III (PIIINP), hyaluronic acid (HA) and MMP-2. A group of 10 alcoholics was studied after significant alcohol consumption and following 2 weeks of abstinence, verified with repeated breath alcohol measurement. Laminin was significantly reduced at 1 week (22%) and at 2 weeks (30%). Similarly, tenascin and undulin were also significantly decreased. By contrast, TIMP-1, collagen VI, PIIINP, HA and MMP-2 did not significantly change. The mode of action of alcohol on these tests is unknown. These differences must be considered when using those measurements to assess liver fibrosis.
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PMID:Effects of alcohol consumption on eight circulating markers of liver fibrosis. 1200 13

Liver fibrosis is potentially reversible after removal of the injurious agent. Fibrosis resolution is characterized by apoptosis of hepatic myofibroblasts and degradation of extracellular matrix components. Matrix metalloproteinase-2 (MMP-2) is involved in matrix remodeling. In the liver, it is synthesized by myofibroblasts, secreted as a proenzyme, and activated by membrane type-MMPs (MT-MMP) such as MT1-MMP. The goal of this work was to determine whether apoptosis induction in human hepatic myofibroblasts modulates the gene expression of MMP-2 and/or its activation by MT1-MMP. Induction of apoptosis by cytochalasin D or C(2)-ceramide did not modulate MMP-2 mRNA expression. In contrast, apoptosis was associated with marked activation of pro-MMP-2, as shown by gelatin zymography, which revealed the presence of the 59-kd active form, whereas untreated cells only expressed the 66-kd proform. SB-203580, a specific inhibitor of p38 (MAPK), selectively abrogated both C(2)-ceramide-induced apoptosis and pro-MMP-2 activation. Apoptosis-induced pro-MMP-2 activation was inhibited by the tissue inhibitors of metalloproteinases (TIMP)-2 but not by TIMP-1, implying involvement of an MT-MMP-mediated process. Induction of apoptosis by cytochalasin D and C(2)-ceramide upregulated MT1-MMP protein expression and MT1-MMP mRNA expression. In conclusion, apoptosis of hepatic myofibroblasts induces pro-MMP-2 activation through increased MT1-MMP expression. HEPATOLOGY 2002;36:615-622.)
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PMID:Apoptosis of human hepatic myofibroblasts promotes activation of matrix metalloproteinase-2. 1219 53

Hepatic fibrosis results from excess extracellular matrix produced primarily by hepatic stellate cells (HSC). In response to injury, HSC differentiate to a myofibroblastic phenotype expressing smooth muscle actin and fibrillar collagens. Relaxin is a polypeptide hormone shown to have antifibrotic effects in fibrosis models. In this study, activated HSC from rat liver were treated with relaxin to determine if relaxin can reverse markers of HSC activation. Relaxin treatment resulted in a decrease in the expression of smooth muscle actin, but had no effect on cell proliferation rate. The levels of total collagen and type I collagen were reduced, while the synthesis of new collagen was inhibited. Furthermore, relaxin caused an increase in the expression and secretion of rodent interstitial collagenase (MMP-13), but there was no effect on the gelatinases MMP-2 or MMP-9. Relaxin also increased secretion of TIMP-1 and TIMP-2. The effective concentration of relaxin to induce these effects was consistent with action through the relaxin receptor. In conclusion, relaxin reversed markers of the activated phenotype of HSC including the production of fibrillar collagen. At the same time, the activity of a fibrillar collagenase was increased. These data suggest that relaxin not only inhibits HSC properties that contribute to the progression of hepatic fibrosis, but also promotes the clearance of fibrillar collagen. Therefore, relaxin may be a useful approach in the treatment of hepatic fibrosis.
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PMID:Inhibition of markers of hepatic stellate cell activation by the hormone relaxin. 1294 68

Apoptosis of hepatic stellate cells (HSC) has previously been shown to occur during spontaneous resolution of experimental liver fibrosis. TIMP-1 has also been shown to have a key role because of its ability to inhibit apoptosis of HSC via matrix metalloproteinase (MMP) inhibition. This has led to further study of novel substrates for MMPs that might impact on HSC survival. N-Cadherin is known to mediate cell-cell contacts in fibroblasts. In this study we demonstrate that N-Cadherin is expressed by activated rat HSC. Furthermore, during apoptosis of HSC, the N-Cadherin is cleaved into smaller fragments. Apoptosis of HSC may be inhibited by TIMP-1. This is associated with reduced fragmentation of N-Cadherin. N-Cadherin may have an important role in supporting HSC survival while N-Cadherin cleavage may play a part in promoting HSC apoptosis in recovery from liver fibrosis.
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PMID:N-Cadherin cleavage during activated hepatic stellate cell apoptosis is inhibited by tissue inhibitor of metalloproteinase-1. 1496 Jan 60

We have reported that Sho-saiko-to (TJ-9) prevents liver fibrosis in vivo. To gain further insights into the effect of TJ-9, the matrix metalloproteinases (MMPs)/tissue inhibitors of metalloproteinases (TIMPs) balance was examined. Hepatic stellate cells (HSCs) were isolated from male Wistar rats and cultured with TJ-9 (0-1000 microg/ml) on uncoated plastic dishes for 4 days. To elucidate the effects on the MMPs/TIMPs balance by TJ-9, quantitative analysis of type IV collagen-degrading activity, gelatin zymography and reverse zymography were carried out. Northern blot analysis was performed to determine the expression of MMP-2, 13 and TIMP-1 mRNAs. TJ-9 treatment resulted in dose-dependent upregulation of MMP-2, 13 mRNA and downregulation of TIMP-1 mRNA up to 500 microg/ml. Gelatin zymography, reverse zymography and quantitative analysis of type IV collagen-degrading activity confirmed that TJ-9 increased MMP-2 activity and prevented TIMP-1, 2 activities in a dose-dependent manner. SB203580 diminished the reduction of mRNA as well as the activity of TIMP-1 by TJ-9 and induction of mRNA as well as the activity of MMP-2. These results show that TJ-9 increased MMP-2, 13 activity with reduced TIMP-1, 2 activities on HSCs possibly via P38 pathway.
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PMID:Herbal medicine Sho-saiko-to (TJ-9) increases expression matrix metalloproteinases (MMPs) with reduced expression of tissue inhibitor of metalloproteinases (TIMPs) in rat stellate cell. 1498 50

Non-alcoholic steatohepatitis (NASH) may progress to liver cirrhosis, and NASH patients with liver cirrhosis have a risk of development of hepatocellular carcinoma. Peroxisome proliferator-activated receptor (PPAR) gamma ligand has recently been reported to have improved the condition of patients with NASH. The aim of this study was to investigate whether pioglitazone, a PPARgamma ligand, has any influence on the animal model of NASH as well as isolated hepatic stellate cells. In vivo, the effects of pioglitazone were examined using the choline-deficient L-amino acid-defined (CDAA)-diet liver fibrosis model. After two weeks, pioglitazone improved hepatic steatosis, prevented liver fibrosis, and reduced preneoplastic lesions in the liver after 10 weeks. Pioglitazone reduced the expression of TIMP-1 and TIMP-2 mRNA without changing MMP-13 mRNA expression compared to the liver fed a CDAA diet alone. In vitro, pioglitazone prevented the activation of hepatic stellate cells resulting in reducing the expression of type I procollagen, MMP-2, TIMP-1, and TIMP-2 mRNA with increased MMP-13 mRNA expression. These results indicate that pioglitazone may be one of the candidates for the benefit drugs for the liver disease of patients with NASH.
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PMID:Pioglitazone prevents hepatic steatosis, fibrosis, and enzyme-altered lesions in rat liver cirrhosis induced by a choline-deficient L-amino acid-defined diet. 1501 44


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