Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0019158 (hepatitis)
 30,205 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Immunohistochemical study was carried out on D-galactosamine hydrochloride (GaIN)-induced subacute hepatitis in rats of JCL: Wistar-TGN (ARGHGEN) 1Nts strain (Mini rats), in which the expression of growth hormone gene is suppressed by the presence of an antisense transgene. Mini rats were given 1000 mg/kg of GaIN once a week for 4 consecutive weeks and killed at 1, 2, 3 and 4 weeks after the first administration. At 1 week after the first administration, proliferation of small epithelial cells positive for both alpha-fetoprotein and cytokeratin 7, i.e. so-called oval cells, was observed in the whole area of each hepatic lobule, and prominent deposition of fibronectin, laminin and type IV collagen was detected around these oval cells. Together with these extracellular matrix components, many activated Ito cells positive for both desmin and alpha-smooth muscle actin were observed. With time, most of the oval cells formed duct-like structures and lost their positive stainability for alpha-fetoprotein, and many Ito cells became inactive. Deposition of fibronectin decreased rapidly from 2 weeks after the first administration. At 4 weeks after the first administration, deposition of laminin was detected only around the duct-like structures, where that of type IV collagen was also still prominent. These results suggest that a large population of oval cells differentiated into bile duct epithelial cells and that Ito cells and extracellular matrix components might play a role in this process.
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PMID:Immunohistochemical study on galactosamine-induced subacute hepatitis in rats of JCL: Wistar-TGN (ARGHGEN) 1 Nts strain (Mini rats). 925 Apr 81

Histopathological and immunohistochemical studies were carried out on D-galactosamine (GalNAc)-induced acute hepatitis in rats of the JCI: Wistar TgN (ARGHGEN) 1 Nts strain (Mini rats), in which expression of the growth hormone gene is suppressed by an antisense transgene. Hepatitis characterized by hepatocellular acidophilic necrosis with inflammatory cell infiltration was most prominent at 2 days after GalNAc (1000 mg/kg)-injection, when proliferation of Ito cells and deposition of fibronectin and laminin were found along the sinusoidal linings. At 72 hours after GalNAc-injection, Ito cell proliferation with deposition of laminin and fibronectin became more prominent, and marked proliferation of small epithelial cells was observed in the periportal area. At 7 days after GalNAc-injection, quite a number of alpha-smooth muscle actin-positive Ito cells, surrounded by abundant fibronectin, laminin and type IV collagen, were still observed in close juxtaposition to rapidly proliferating small epithelial cells. The small epithelial cells were found to be positive for both alpha-fetoprotein and cytokeratin 7 and were therefore considered to be so-called oval cells. The results suggest that there may be some relation between oval cell proliferation, Ito cell activation and extracellular matrix accumulation in GalNAc-induced acute hepatitis in Mini rats.
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PMID:Prolonged oval cell proliferation with Ito cell activation and extracellular matrix accumulation in galactosamine-induced acute hepatitis in mini rats. 930 54

The inbred mutant strains of Long-Evans Cinnamon (LEC) rats spontaneously develops acute hepatitis as a result of abnormal copper accumulation, followed by chronic hepatitis, cholangiofibrosis and hepatocellular carcinoma. To shed some light on the role of macrophages in the liver failure, immunohistochemical methods were used to investigate the kinetics of macrophage populations in the liver of male LEC rats, in relation to the appearance of myofibroblastic cells and hepatocyte apoptosis. Rats examined at 24 weeks of age and moribund rats killed at 22-25 weeks of age had increased serum concentrations of aspartate aminotransferase and alanine aminotransferase, with jaundice and histological changes indicative of hepatic failure, whereas rats examined at 8, 12, 16 or 20 weeks old showed no such abnormal findings. Immunolabelling with ED1 (a monoclonal antibody recognizing rat macrophages) and ED2 (a monoclonal antibody specific for rat resident macrophages) revealed that numbers of blood monocyte-derived macrophages and Kupffer cells began to increase markedly at 16 weeks of age (before the onset of hepatitis). However, alpha-smooth muscle actin (SMA)-positive myofibroblastic cells (modulated perisinusoidal cells) and hepatocyte apoptosis, demonstrable by the TUNEL method, were rarely seen at 8, 12, 16, 20 or 24 weeks. There was no close relationship between macrophage expansion and the appearance of myofibroblastic cells or hepatocyte apoptosis. In moribund rats, only a few SMA-positive cells were seen in the periportal zones; hepatocytes undergoing apoptosis increased in number, and macrophages engulfing apoptotic bodies were observed occasionally, suggesting that apoptosis was related to hepatic failure as an early event. In addition, immunohistochemical examination demonstrated abnormal deposits of laminin along the sinusoids from 20 weeks, as an initial extracellular matrix protein in LEC rat livers.
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PMID:Macrophage populations and apoptotic cells in the liver before spontaneous hepatitis in Long-Evans Cinnamon (LEC) rats. 1020 30

Synaptophysin is a protein involved in neurotransmitter exocytosis and is a neuroendocrine marker. We studied synaptophysin immunohistochemical expression in 35 human liver specimens (normal and different pathological conditions), in rat models of galactosamine hepatitis and carbon tetrachloride-induced cirrhosis, and in freshly isolated rat stellate cells. Synaptophysin reactivity was present in perisinusoidal stellate cells in both human and rat normal liver biopsies. The number of synaptophysin-reactive perisinusoidal cells increased in pathological conditions. Double staining for alpha-smooth muscle actin and synaptophysin, detected by confocal laser scanning microscopy, unequivocally demonstrated colocalization of both markers in lobular stellate cells. In addition, freshly isolated rat stellate cells expressed synaptophysin mRNA (detected by polymerase chain reaction) and protein. Finally, electron microscopy showed the presence of small electron translucent vesicles, comparable to the synaptophysin-reactive synaptic vesicles in neurons, in stellate cell projections. We conclude that synaptophysin is a novel marker for quiescent as well as activated hepatic stellate cells. Together with the stellate cell's expression of neural cell adhesion molecule, glial fibrillary acidic protein, and nestin, this finding raises questions about its embryonic origin and its differentiation. In addition, the presence of synaptic vesicles in stellate cell processes suggests a hitherto unknown mechanism of interaction with neighboring cells.
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PMID:Synaptophysin: A novel marker for human and rat hepatic stellate cells. 1059 12

The myofibroblastic transformation of hepatic stellate cells (HSC; also known as Ito cells) usually occurs following necrosis of adjacent liver cells. No report has previously found that such a transformation occurs in herpes simplex virus (HSV) hepatitis. We present an autopsy case of HSV hepatitis with myofibroblastic transformation of HSC that is different from the usual transformation of HSC. The patient was a 66-year-old woman who had received various therapies for cutaneous T-cell lymphoma. An autopsy revealed submassive hepatic necrosis with hemorrhage due to HSV hepatitis. HSV infection was confirmed by DNA in situ hybridization in liver tissue. Immunohistochemical staining for alpha-smooth muscle actin (ASMA) showed a strong positive reaction in almost all of the HSC in non-necrotic areas. However, in necrotic areas, the HSC were completely negative for ASMA. These findings indicate that not only liver cells but also HSC can become necrotic in HSV hepatitis. In contrast, in non-necrotic areas, almost all of the HSC showed active transformation to myofibroblasts.
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PMID:Adult-onset herpes simplex virus hepatitis with diffuse myofibroblastic transformation of hepatic stellate cells (Ito cells) in non-necrotic areas. 1135 Jun 12

To characterize cellular responses during hepatic regeneration, we examined 13 explant livers and 5 liver allografts by immunohistochemistry for cytokeratin 7, HepPar1, CD68, alpha-smooth muscle actin (alpha-SMA) and proliferating cell nuclear antigen as well as reticulin and Masson-trichrome staining. Within a week after liver damage, elongated CD68-positive cells were detected along the border of necrotic area. The number of alpha-SMA-positive cells was slightly increased along the sinusoids. Ductular proliferation or fibrosis was negligible. After one or two weeks, the size and number of CD68-positive cells were markedly increased. alpha-SMA-positive cells increased in number within lobules and portal tracts. Ductular proliferation occurred predominantly at the limiting plate or along the border of necrotic areas. After one month, necrotic parenchyma was replaced by many ductules, CD68-positive cells, alpha-SMA-positive cells. Nodules of regenerating hepatocytes and irregular fibrosis were diffusely present. Other nonparenchymal cells were not significantly changed. These observations indicate that chronological interaction between nonparenchymal and parenchymal cells occur during the course of human hepatic regeneration and suggest extensive porto-periportal fibrosis more than a few months after the onset of fulminant hepatitis is a major indicator of chronic functional impairment necessitating liver transplantation.
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PMID:Parenchymal and nonparenchymal cellular responses in human hepatic regeneration. 1151 89

Canine chronic hepatitis (CCH) is a progressive inflammatory disease of unknown etiology. To characterize the inflammatory infiltrate, 16 dogs with CCH were selected and classified into three groups based on the stage of fibrosis, as evaluated with Masson's trichrome stain. The inflammatory infiltrate in each liver section was immunohistochemically characterized and evaluated using CD3, lysozyme, lamba and kappa light chain, and alpha-smooth muscle actin antibodies. Numerous breeds were affected, and middle-aged females predominated in this select group. Necroinflammatory activity progressively increased and then waned as the hepatitis progressed to cirrhosis. CD3+ lymphocytes were the most numerous lymphoid cells in dogs with CCH. Degenerate hepatocytes were occasionally surrounded by CD3+ lymphocytes. Necrosis was positively correlated with the number of CD3+ lymphocytes. The lamba and kappa light chain-positive cell infiltrate was variable but generally mild. A positive correlation between the lambda and kappa light chain-positive cells and the portal alpha-smooth muscle actin was found. The number of alpha-smooth muscle actin-positive cells (myofibroblasts) in portal triads and fibrous septa was positively correlated with the stage of fibrosis. In contrast, no correlation was found between the number of lysozyme-positive cells (Kupffer cells) and the stage of fibrosis. These results further support the idea of an immune-mediated process in CCH and suggest that periductular myofibroblasts play an important role in canine liver fibrogenesis.
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PMID:Characterization of the inflammatory infiltrate in canine chronic hepatitis. 1173 95

Hepatic stellate cells have been considered the most important cell-type involved in hepatic fibrogenesis. Proliferation and differentiation of hepatic stellate cells into myofibroblast-like cells has been related to the development of liver fibrosis. The alpha-actin expressed by hepatic stellate cells was considered a marker of their activation to myofibroblast-like cell. The aim of this study is to evaluate the changes in morphology, distribution, percentage and alpha-smooth muscle actin expression of hepatic stellate cells in normal and cirrhotic livers, and to correlate activated hepatic stellate cells with the progression of fibrosis. Human liver biopsies (n=121) were divided in five groups: 1) normal livers (controls); 2) cirrhosis post-HCV hepatitis; 3) cirrhosis post-HBV hepatitis; 4) non viral related cirrhosis; 5) recurrent HCV hepatitis after orthotopic liver transplantation. Samples immunostained with anti alpha-smooth muscle actin antibody by immunoperoxidase method were semi-quantitatively evaluated. Liver fibrosis was quantified by computer image analysis on specimens stained with Masson's trichrome. In normal adult livers stellate cells were very rarely stained for alpha-smooth muscle actin. In cirrhotic livers, a strongly enhanced percentage of stellate cells expressing alpha-smooth muscle actin was detected in cirrhotic fragments with respect to the control group, with a significant correlation between alpha-smooth muscle actin positive stellate cells and the volume fraction of fibrosis. Moreover, liver biopsies of recurrent hepatitis revealed an increased number of activated stellate cells compared to normal livers, and intermediate volume fraction of fibrosis. These results confirmed that a direct correlation existed between activated stellate cells and the progression of fibrosis. Alpha-smooth muscle actin confirmed to be a reliable marker of hepatic stellate cells activation also in precocious stages of the disease.
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PMID:Activated hepatic stellate cells in liver cirrhosis. A morphologic and morphometrical study. 1571 57

During fibrosis, the extracellular matrix (ECM) is continuously remodeled and increases in volume due to the production of various proteins. We studied the distribution of tenascin-C (TN-C) and the correlation of TN-C with the necro-inflammatory activity and expression of alpha-smooth muscle actin (alpha-SMA), cytokeratin 7 (CK7), and CD3+ T-lymphocytes in canine chronic hepatitis. This was analyzed using immunohistochemistry and semiquantitative scoring. We used 3 groups (n = 19) of dogs: group 1 (n = 5) with neonatal hepatitis/lobular dissecting hepatitis (NH/LDH), group 2 (n = 8) with chronic hepatitis/cirrhosis (CH/CIRR), and group 3 (n = 6) consisting of healthy animals. In normal livers, TN-C was localized in Disse's space and around bile ducts and blood vessels. In CH/CIRR livers, TN-C was localized at the periphery of the regenerating nodules and was conspicuous in the bridging fibrous bands. In NH/LDH, TN-C was diffusely distributed along the reticular fibers that dissected between single cells or groups of hepatocytes. alpha-SMA in the normal hepatic parenchyma showed an irregular distribution along the perisinusoidal linings. In other groups, alpha-SMA was increased in fibrotic septa and perisinusoidal linings. In normal livers, CK7 was positive in bile ducts. In other groups, CK7-expressing cells were conspicuous in the portal-parenchymal interface, the periphery of the regenerative nodules, and the degenerated parenchyma. The pattern of CD3+ lymphocytes was inversely proportional to that of TN-C. These results also showed that TN-C is strongly correlated with increased fibrotic stage, inflammatory activity, and expression of CK7 and alpha-SMA. TN-C, CK7, and CD3 expression did not differ between diagnostic groups.
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PMID:Tenascin-C in chronic canine hepatitis: immunohistochemical localization and correlation with necro-inflammatory activity, fibrotic stage, and expression of alpha-smooth muscle actin, cytokeratin 7, and CD3+ cells. 1803 93

Hepatic COX-2 overexpression is sufficient to induce hepatitis, but its role on liver fibrosis remains unknown. We aim to elucidate possible biological effects of COX-2 in liver fibrosis using both gain-of-function and loss-of-function mouse models. COX-2 transgenic (TG) mice that specifically overexpress the human COX-2 cDNA in the liver, knockout (KO), and wild type (WT) mice were studied in two different murine fibrosis models induced by carbon tetrachloride (CCl(4)) injection or methionine and choline-deficient (MCD) diet. Liver injury was assessed by serum ALT and bilirubin levels and histological examination. Hepatic collagen content was determined by picrosirius red stain morphometry assay and quantitation of hydroxyproline. Hepatic stellate cell (HSC) activation was determined by immunohistochemical analysis of alpha-smooth muscle actin (alpha-SMA). mRNA expression of fibrogenic genes was assayed by real-time quantitative PCR. COX-2 protein was overexpressed in the liver of TG mice compared with WT littermates. CCl(4) or MCD-induced liver fibrotic injury was equally severe in TG and WT mice, as demonstrated by similar elevated levels of hepatic collagen contents. Enhanced COX-2 expression in TG liver did not affect HSC activation and fibrogenic gene expression upon CCl(4) or MCD treatment. Importantly, CCl(4)-treated KO mice did not show significant difference in liver fibrotic damage and fibrogenic gene expression compared with the WT counterparts. This is the first report on the effect of COX-2 in liver fibrosis based on genetic mouse models. The results suggest that COX-2 does not appear to mediate the development of liver fibrosis.
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PMID:Elucidation of the role of COX-2 in liver fibrogenesis using transgenic mice. 1850 50


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