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)

Peritoneal liver biopsy specimens from eight patients with hepatitis B associated cirrhosis, complicated by hepatocellular carcinoma, were studied for identification and localisation of myofibroblasts. The avidin-biotin peroxidase complex technique was used on paraffin wax sections, using monoclonal antibodies for actin and desmin, and ultrastructural examination was performed. Myofibroblasts were found in seven of the eight cirrhotic specimens and in all eight tumour specimens. They were identified in the fibrotic areas by the immunohistochemical technique, but ultrastructural examination disclosed their presence in the perisinusoidal space and between tumour cells.
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PMID:Myofibroblasts in hepatitis B related cirrhosis and hepatocellular carcinoma. 131 87

Proliferating lipocytes (fat-storing cells or perisinusoidal stellate cells of the liver) were detected by in vivo incorporation of bromodeoxyuridine (BrdU) in an experimental model of cirrhosis in the rat by dimethylnitrosamine. Lipocytes were identified by sequential double immunohistochemical staining on frozen sections using anti-desmin antibodies as a marker of cytoplasmic intermediate filaments followed by anti-BrdU antibodies to identify S-phase nuclei in animals treated for 7, 14 or 21 days. The number of desmin-positive (lipocytes) and desmin-negative (Kupffer and endothelial cells) sinusoidal cells incorporating BrdU was recorded. The labelling index of lipocytes was calculated as the percentage of BrdU-labelled desmin-positive cells with respect to total number of lipocytes. In control animals, when the total number of lipocytes was 153.9 +/- 11/mm2 (mean +/- 1 S.E.) the number of desmin-positive S-phase sinusoidal cells never exceeded 6.8 +/- 1.2/mm2 with a maximum labelling index of 4.3 +/- 0.5%. At 7 days of treatment, the values were respectively 236 +/- 26.5/mm2, 53.2 +/- 5.9/mm2 and 22.6 +/- 0.5% (p less than 0.001 vs. controls), while, at 21 days they were 272.5 +/- 21.2/mm2, 23.3 +/- 4.0/mm2 and 8.5 +/- 1.1% respectively (p less than 0.01). These results show that hyperplasia of lipocytes represents an early reaction to dimethylnitrosamine-induced liver injury. The local accumulation of lipocytes appears to occur in areas where fibrous septa develop later on.
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PMID:Quantitative analysis of proliferating sinusoidal cells in dimethylnitrosamine-induced cirrhosis. An immunohistochemical study. 144 3

That Ito cells in rat liver express desmin was confirmed by immunohistochemical technique. Anyhow, changes of desmin-positive cells, lysozyme-positive cells and fibronectin were further studied in experimental cirrhosis of rat. It was found that desmin-positive cells, with the transitional features between Ito cells and myofibroblasts or fibroblasts under electron microscope, increased in number and expression of desmin in the necrotic areas as well as in the cellular fibrous septa, but decreased in number in the fibrous septa except those areas close to the edges of the septa. These results suggested that Ito cells, myofibroblasts and fibroblasts may belong to the same cellular system and play an important role in the pathogenesis of cirrhosis. Meanwhile, it was also noted that changes of both fibronectin and lysozyme-positive cells were correlated with those of desmin-positive cells. These provide evidence in vivo that fibronectin and Kupffer cells may exert certain effects on the migration and proliferation of Ito cells in cases of liver cirrhosis.
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PMID:[Dynamic changes of Ito cells in experimental cirrhosis of rat]. 191 24

It has been suggested that perisinusoidal liver cells (PSC) play a pivotal role in the pathogenesis of fibrocontractive changes. Using light and electron microscopic immunolocalization techniques, a series of 207 normal and pathologic human liver specimens were evaluated for the expression of alpha smooth muscle (SM) actin and desmin in this and other nonparenchymal cell types. In normal adult liver tissue, PSCs were practically devoid of desmin and exceptionally stained for alpha-SM actin, whereas this actin isoform frequently was encountered in PSCs from the embryonic to the adolescent period. A broad spectrum of pathologic conditions was accompanied by the presence of alpha-SM actin containing PSCs; these were detected preferentially in periportal or perivenular zones according to the predominant location of the underlying hepatocellular damage. The occurrence of this PSC phenotype generally was associated with fibrogenesis and was in some cases detected earlier than overt collagen accumulation. Fibrous bands subdividing liver tissue in cirrhosis and focal nodular hyperplasia, as well as desmoplastic reaction to malignant tumors, contained alpha-SM actin-rich cells admixed with variable proportions of cells coexpressing desmin. In end stages, this population was less numerous than in active fibrotic or cirrhotic processes. Using immunogold electron microscopy, alpha-SM actin was localized in microfilament bundles of typical PSCs. Our results are compatible with the assumption that the appearance of alpha-SM actin and desmin-expressing myofibroblasts results at least in part from a phenotypic modulation of PSCs.
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PMID:Modulation of alpha smooth muscle actin and desmin expression in perisinusoidal cells of normal and diseased human livers. 202 9

Hepatic fibrosis represents an important stage in the progression of chronic liver disease to cirrhosis. In the present paper we have investigated whether capsaicin-sensitive neuropeptide-containing sensory neurons may participate in the development of liver fibrosis. The expression of hepatic fibrosis induced by common bile duct obstruction has been studied both in capsaicin- and vehicle-treated rats. Common bile duct-induced liver fibrosis was less marked in capsaicin-treated rats than in vehicle-treated rats. Diffuse alterations of liver parenchyma structure with marked collagen deposition and nodular regeneration occurred 8 weeks after common bile duct ligation in vehicle-treated animals, while none of the capsaicin-treated rats exhibited the formation of complete connective septa altering the parenchyma architecture. Both vehicle- and capsaicin-treated rats showed an increasing number of desmin-positive cells in the perivenular zone, but the density of these cells was lower in treated animals than in untreated rats. The hydroxyproline content of the liver increased after common bile duct ligation in a time-dependent manner. Eight weeks after bile duct obstruction vehicle-treated rats showed a 7-fold increase of liver collagen content in comparison to normal animals. This enhancement was about 3.5-fold in capsaicin-treated rats. These findings raise the possibility that the peripheral release of neuropeptides stored in sensory nerves might participate in the development of liver fibrosis following common bile duct obstruction.
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PMID:Effect of sensory denervation with capsaicin on liver fibrosis induced by common bile duct ligation in rat. 229 20

The present study is concerned with the early events associated with the development of cirrhosis induced by dimethylnitrosamine (DMN). The antigenic expression of MHC class II components (Ia) and of some intermediate filament proteins (vimentin and desmin) have been studied by immunohistochemistry and the findings correlated with ultrastructural data. Micronodular cirrhosis developed after 3 weeks of treatment with DMN but enhanced expression of Ia antigen on macrophages and on infiltrating lymphocytes was observed after 1 week, before the formation of septa, suggesting that immune-mediated mechanisms are involved in the response to DMN-induced liver injury. The expression of vimentin and of desmin also increased at an early stage and at 3 weeks the septa were outlined by cellular elements showing positivity for both intermediate filament proteins. In keeping with these observations, ultrastructural data showed active division of macrophages in situ, infiltration of the parenchyma by T and B lymphocytes, activation of lipocytes (Ito cells) showing evidence of mitosis, and the presence of transitional elements between lipocytes, myofibroblasts and fibroblasts. This experimental model may be helpful in understanding the relationship between immune-mediated response to liver injury and development of hepatic fibrosis.
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PMID:Dimethylnitrosamine-induced cirrhosis. Evidence for an immunological mechanism. 292 2

Male F-344 rats were treated for 10 weeks either with CCl4 (0.2 ml/kg, per os, twice a week) or with CCl4 (same as above) and phenobarbital (0.2 g/l in drinking water). Liver fibrosis and cirrhosis developed in both treated groups, and was confirmed histologically. Cirrhosis was more frequent after the CCl4 + phenobarbital treatment. The collagen content of the liver, measured by morphometry and biochemically, was significantly higher in the animals of the group treated with CCl4 + phenobarbital than in the animals treated only with CCl4. Specially altered fat-storing cells (Ito cells) were found in the periportal and septal fibrotic areas in direct proportion to the amount of fibrosis and cirrhosis. They were identified as altered fat-storing cells by their desmin content and Vitamin A storing capability. This study demonstrated that these cells were enlarged and contained neutral fat, lipofuscin and PAS-positive material. The potential role of GAG-containing FSC in fibrogenesis is discussed.
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PMID:Glycosaminoglycan containing fat-storing cells in hepatic fibrogenesis. 315 42

In the last years, considerable advances have been made in the study of the proteins and polypeptides of the cytoskeleton, and its three main components: microfilaments (MF), intermediate filaments (IMF) and microtubules (MT). The principal properties of these elements and those of many associated proteins are recalled. The actin MF are mainly involved in cell contractility, the IMF in cell shape, while the MT and their associated proteins are involved in intracellular transport. Some pathological modifications of the cytoskeleton will be considered. In the liver, accumulations of keratin result in the formation of Mallory's hyalin, found in several types of cirrhosis and hepatomas. In muscle, accumulations of desmin are observed in various myopathies. An accumulation of alpha-actinin at the Z bands characterizes nemalin myopathy. In several forms of hemolytic anemias, alterations of the membranous cytoskeletal components of the red blood cells--spectrin, ankyrin, actin--may explain their abnormal shape and excessive fragility. In the nervous system, many pathological conditions are related to abnormal cytoskeletal components. In Parkinson's disease, Lewy bodies are an accumulation of neurofilaments (IMF). In Alzheimer's disease, and some related conditions, the intraneuronal tangles are associated with modifications of MT and neurofilaments. The role of MT and in particular of the MT-associated protein tau, as demonstrated recently, confirms the involvement of the MT. The observed disturbances of MT-related axonal flow may explain some of the known functional changes in these forms of dementia.
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PMID:[Pathology of the cytoskeleton]. 329 78

Multiple injections of D-galactosamine induce liver fibrosis and cirrhosis in rats. The purpose of this immunopathological study was to correlate inflammation and hepatic extracellular matrix remodeling after repeated administration of galactosamine. Rats were given 10, 20, 30, 40, 60, 80, 100 and 140 intraperitoneal injections of D-galactosamine (500 mg/kg body wt, three times weekly). Controls received injections of saline solution. Cryostat sections of liver tissue obtained on biopsy or autopsy were immunostained with a panel of monoclonal and polyclonal monospecific antibodies reactive with macrophages, T and B lymphocytes, desmin, the extracellular matrix components fibronectin; laminin; collagen types I, III and IV; and the fibronectin receptor alpha 5 beta 1. Total RNA was extracted and Northern-blot analysis was performed with a specific cDNA probe for rat collagen type III. Spotty liver cell necrosis and mild portal and parenchymal inflammation was seen after 10 injections of galactosamine. After 20 to 40 injections, expansion of protal tracts, prominent bile ductular proliferation and gradual formation of fibrous septa were encountered with the development of cirrhosis at later intervals. These progressive histological changes were paralleled by a gradual increase of desmin-positive cells in developing septa with deposition of fibronectin; collagen types I, III, and IV; and laminin. Northern-blot analysis showed that this accumulation of extracellular matrix was not accompanied by increase of mRNA for collagen type III. In conclusion, repetitive administration of galactosamine causes progressive liver disease with prominent bile ductule proliferation and development of fibrous septa. These pathological alterations bear some resemblance to the morphological changes in chronic biliary disease in human beings.
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PMID:Immunohistochemical study of hepatic fibrosis induced in rats by multiple galactosamine injections. 750 72

The association of the common bile duct (CBD) ligation followed by CCl4 and progesterone treatment leads to liver cirrhosis in rats in 28 days. The resulting cirrhosis shows mixed aspects: it starts as biliary cirrhosis and goes on to nodular and periportal pseudolobular form of cirrhosis. Because Ito cells are the main source of extracellular matrix components, changing their phenotype from quiescent Ito cells to myofibroblast like cells, the purpose of this study was to evaluate the behaviour of Ito cells by the immunohistochemistry technique of desmin and alpha-SM-actin after these treatments. After CBD ligation alone, positive Ito cells for desmin remarkably proliferate around adenomateous areas; after treatment with CCl4 alone desmin positive stellate cells are more numerous. Desmin positive Ito cells in CBD ligation and CCl4 treatment were even larger than those of the previous lots. Significant differences were not observed after progesterone and for the alpha-SM-actin positive cells.
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PMID:[Perisinusoidal stellate cells in a model of experimental liver cirrhosis]. 756 65


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