OBJECTIVETo establish a modified rat model of liver cancer with concurrent cirrhosis for the study of carcinogenesis characteristics and drug intervention of liver cancer.

METHODSFifty male Wistar rats weighing 100-120 g were randomly divided into normal control group (20 rats) and model group (30 rats). In the model group, the rats were subjected to intraperitoneal injection of 50 mg/kg DEN N-diethylnitrosamine (DEN) twice a week for 4 consecutive weeks, followed then by weekly injections for another 10 weeks. The control rats received injections of 0.1 ml saline in the same manner. At 2, 4, 8, 12, 14, and 18 weeks, 3 rats from each group were sacrificed for assessing tumor formation and liver cirrhosis.

RESULTSLiver cancer with concurrent cirrhosis was induced successfully after 14 weeks of DEN injections. At the 14th week, 3 out of the 5 rats were found to have cirrhosis and LC, and at the 18th week, all the 3 rats examined had cirrhosis and liver cancer. The total carcinogenesis rate in the rats was 75% at 18 weeks with an overall mortality of 33%.

CONCLUSIONThis approach to establishing rat models of liver cancer with concurrent cirrhosis requires simple operation, shortens the time of carcinogenesis, and ensures a high success rate of carcinogenesis and a low mortality rate. The carcinogenesis characteristics in this model are similar to those in human.

Animals ; Liver Cirrhosis, Experimental ; complications ; pathology ; Liver Neoplasms, Experimental ; etiology ; pathology ; Male ; Rats ; Rats, Wistar

Animals ; Bile Duct Diseases ; Liver Cirrhosis, Experimental ; Rats

OBJECTIVETo investigate the expression of the lysosomal enzyme acid sphingomyelinase (ASMase) in alcohol-induced hepatic fibrosis using a rat model.

METHODSThe model of liver fibrosis was induced by administration of alcohol and high fat diet using 20 rats. Six rats given no alcohol and normal diet served as the control group. Real-time PCR, western blotting, and immunohistochemistry were used to evaluate fibrosis-related changes in the mRNA and protein expressions of ASMase.

RESULTSThe fibrotic liver tissues of the model rats showed significantly higher expression levels of ASMase than the non-fibrotic liver tissues of the control rats (P less than 0.05).

CONCLUSIONExpression of ASMase is increased in the fibrotic liver tissue of an alcohol-induced hepatic fibrosis rat model, suggesting that this lysosomal enzyme may contribute to development of this disease condition.

Animals ; Liver ; enzymology ; Liver Cirrhosis, Alcoholic ; enzymology ; Liver Cirrhosis, Experimental ; enzymology ; Male ; Rats ; Rats, Sprague-Dawley ; Sphingomyelin Phosphodiesterase ; metabolism

BACKGROUND/AIMS: The reactive oxygen species from thioacetamide (TAA) induces rat liver cirrhosis that resembles the human disease, and it can serve as a suitable animal model for studying human liver cirrhosis. The aim of this study was to identify the molecular protein signatures via a proteomics approach with using a rat model with TAA-induced liver cirrhosis. METHODS: Male Wistar rats were treated with 0.3 g/L TAA in their drinking water. The animals were then sacrificed at 9 and 30 weeks after TAA administration. The development of liver cirrhosis was observed with histological study. The livers were processed for proteins extraction and the proteins were analyzed by 2-dimensional electrophoresis. The proteins were identified by matrix-assisted laser desorption ionizing time-of-flight mass spectrometry and this was validated by immunohistochemical staining. RESULTS: On the proteomics analysis of the liver tissues, a total of 88 proteins showed significant change in their expression between the controls and the cirrhotic rats. When the proteins were categorized by their function, they included ECM/cellular skeleton, cell proliferation/death signal, metabolism, DNA damage/stress and immune response related proteins. The level of expression gradually increased up to 30 weeks for interleukin-6 (IL-6) precursor, transforming growth factor-beta (TGF-beta) induced protein, TIMP-1 and MMP-9. Cytochrome P450 2B, which is required for the metabolic activation of TAA, also showed the same increasing pattern. In contrast, the expression level of the proteins did not show a significant change at 9 weeks, but this increased to 3-fold at 30 weeks for carbonic anhydrase VII, ras related protein Rab 6, Annexin A2, neurofibromatosis type 2 and aldehyde dehydrogenase. CONCLUSIONS: This study showed that there is a repertoire of proteins during the development of liver cirrhosis via TAA. In this model, IL-6, TGF-beta, MMP-9 and TIMP-1 were reconfirmed as the molecular signatures during the development of TAA-induced liver cirrhosis.
Thioacetamide ; Rats, Wistar ; Rats ; Proteomics ; Proteins/*metabolism ; Male ; Liver Cirrhosis, Experimental/*metabolism ; Liver/*metabolism ; Animals

Animals ; Cyclophilins ; metabolism ; Liver ; metabolism ; pathology ; Liver Cirrhosis, Experimental ; metabolism ; Rats ; Rats, Wistar

Animals ; Carbon Tetrachloride Poisoning ; Diabetes Mellitus, Experimental ; complications ; Liver Cirrhosis, Experimental ; chemically induced ; complications ; pathology ; Male ; Rats ; Rats, Sprague-Dawley

Animals ; Leptin ; pharmacology ; Liver Cirrhosis, Experimental ; metabolism ; pathology ; Male ; Mice ; Mice, Inbred C57BL ; Superoxide Dismutase ; metabolism

Animals ; Endostatins ; blood ; Estrogens ; therapeutic use ; Liver Cirrhosis, Experimental ; drug therapy ; metabolism ; Male ; Rats ; Rats, Wistar

BACKGROUNDIn the process of hepatic fibrosis, the accumulation of collagen fibers is strongly related to the hepatic function. The aim of this study was to investigate the three-dimensional architecture of the collagen network in the liver of rats with hepatic fibrosis.

METHODSHealthy adult male Wistar rats (n = 32) were randomly divided into a control group (n = 16) and a hepatic fibrosis group (n = 16). In the control group, the rats were treated with peanut oil while the rats in hepatic fibrosis group were treated for 10 weeks with 60% CCl(4) diluted in peanut oil. The quantity of collagen fibers was detected by Western blotting; distribution of the collagen was detected by sirius red staining and polarized microscope; the three-dimensional architecture of collagen in the liver was observed under the scanning electron microscope after fixed tissues were treated with cell-maceration using NaOH. Statistical analysis was performed using the u test.

RESULTSThe quantity of collagen fibers increased significantly in the hepatic fibrosis group. With the aggravation of hepatic fibrosis, collagen fibers gradually accumulated. They interlaced the reticulation compartment and formed a round or ellipse liver tissue conglomeration like a grape framework that was disparate and wrapped up the normal liver lobule. The deposition of collagen fibers was obvious in adjacent hepatic parenchyma, especially around the portal tracts.

CONCLUSIONOur experiment showed the collagen proliferation and displays clearly the three-dimensional architecture of collagen fibers in rat liver with hepatic fibrosis by scanning electron microscope. It can provide a morphological foundation for the mechanisms of changed haemodynamics and portal hypertension in hepatic fibrosis.

Animals ; Blotting, Western ; Collagen ; ultrastructure ; Liver Cirrhosis, Experimental ; pathology ; Male ; Microscopy, Electron, Scanning ; Rats ; Rats, Wistar

Angiotensinogen ; metabolism ; Animals ; Liver Cirrhosis, Experimental ; metabolism ; pathology ; Rats ; Rats, Sprague-Dawley ; Renin-Angiotensin System