No abstract available.
Thioacetamide*

To investigate the earlier cellular alterations(Glucose-6-Pase activity and morphologic features) caused by a hepatotoxin, thioacetamide (TAA), a single dose of the agent (200mg per kg of body weight) was given intraperitoneally to mice, which were sacrificed at intervals of 4, 8 or 16 hours after corresponding treatments. For histochemical study of glucose-6-phosphatase (G6Pase) activity, unfixed frozen sections were incubation of the Wachstein and Meisel medium and stained. The smallest pieces of liver tissue were fixed in glutaraldehyde and osmic acid, and stained by the routine electron-microscopic techniques. Some pieces of liver were fixed in 10% formalin, embedded in paraffin, and stained with hematoxylin and eosin. There was a rapid and progressive loss of G6Pase activity, in an orderly time sequence, in the experimental group. There were also morphologic changes: loss of cytoplasmic basophilia, cell infiltration and necrosis in the centrilobular and intermediate zones, and an increase of sER, small vesicles and ribosomes in the cytoplasm of hepatocytes, the marked changes of nuclei and nucleoli, and a slight increase of lipid droplets in the cytoplasm at 16 hours after intoxication. The correlation between these cellular alterations was discussed in view of mechanisms in the hepatotoxic action.
Acetamides/adverse effects* ; Animal ; Glucose-6-Phosphatase/metabolism* ; Liver/drug effects* ; Liver/enzymology ; Liver/ultrastructure ; Male ; Mice ; Thioacetamide/adverse effects* ; MH - ; Substances: ; Acetamides ; Thioacetamide ; Glucose-6-Phosphatase

To investigate the earlier cellular alterations(Glucose-6-Pase activity and morphologic features) caused by a hepatotoxin, thioacetamide (TAA), a single dose of the agent (200mg per kg of body weight) was given intraperitoneally to mice, which were sacrificed at intervals of 4, 8 or 16 hours after corresponding treatments. For histochemical study of glucose-6-phosphatase (G6Pase) activity, unfixed frozen sections were incubation of the Wachstein and Meisel medium and stained. The smallest pieces of liver tissue were fixed in glutaraldehyde and osmic acid, and stained by the routine electron-microscopic techniques. Some pieces of liver were fixed in 10% formalin, embedded in paraffin, and stained with hematoxylin and eosin. There was a rapid and progressive loss of G6Pase activity, in an orderly time sequence, in the experimental group. There were also morphologic changes: loss of cytoplasmic basophilia, cell infiltration and necrosis in the centrilobular and intermediate zones, and an increase of sER, small vesicles and ribosomes in the cytoplasm of hepatocytes, the marked changes of nuclei and nucleoli, and a slight increase of lipid droplets in the cytoplasm at 16 hours after intoxication. The correlation between these cellular alterations was discussed in view of mechanisms in the hepatotoxic action.
Acetamides/adverse effects* ; Animal ; Glucose-6-Phosphatase/metabolism* ; Liver/drug effects* ; Liver/enzymology ; Liver/ultrastructure ; Male ; Mice ; Thioacetamide/adverse effects* ; MH - ; Substances: ; Acetamides ; Thioacetamide ; Glucose-6-Phosphatase

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

Using animal models for the study of biliary disease is useful not only in promoting insight in its pathogenesis, but also in developing new therapeutic agents in various biliary diseases. It is generally accepted that gallstone formation can be formed by certain diets according to the characteristics of cholesterol or pigment gallstones. We can use high cholesterol diet supplement in mice or hamsters as a reliable animal model of cholesterol gallstone. Pigment gallstones are formed in hamsters or guinea pigs with a supplement of high carbohydrate diet. The animal model of cholangiocarcinoma is established by thioacetamide supplement in rats or liver fluke infection in hamsters. The Guinea pig is useful as a model for the study of the sphincter of Oddi motility. The overall advantages of using animal models and the specific advantages and disadvantages of various animal species are briefly discussed.
Animals* ; Cholangiocarcinoma ; Cholesterol ; Cricetinae ; Diet ; Fasciola hepatica ; Gallstones ; Guinea Pigs ; Mice ; Models, Animal* ; Rats ; Sphincter of Oddi ; Thioacetamide

BACKGROUND/AIMS: Tc-DTPA-galactosylated serum albumin (GSA) is a new liver imaging agent that specifically binds to asialoglycoprotein receptor, which resides exclusively on the plasma membrane of mammalian hepatocytes. To evaluate the usefulness of hepatic scintigraphy with Tc-GSA in the assessment of hepatic function, we have investigated serial changes in organ uptakes of Tc-GSA in mice with thioacetamide-induced hepatic injury and compared to changes in histology or levels of hepatic enzymes. MATERIALS AND METHODS: Acute hepatic injuries were induced by intraperitoneal injection of thioacetamide in ICR (Institute of Cancer Research) mice. Hepatic injuries were serially assessed by either light microscopic examination of liver slices or measurement of hepatic enzymes. The biodistribution of Tc-GSA was measured in liver and each excised organs using gamma counter. RESULTS: Hepatic injuries in light microscopic examination were not evident at 12 hours after injection of thioacetamide but resulted in maximal centrilobular necrosis and inflammation at 24 hours. These histologic changes were progressively improved upto 72 hours. Studied hepatic enzymes were elevated at 6 hours and reached to maximal level at 24 hours after administration of thioacetamide and declined progressively after then. Hepatic uptake of Tc-GSA was lowest at 6 hours after administration of thioacetamide and serially recovered until 72 hours. CONCLUSION: The degree in the decrease of hepatic uptake of Tc-GSA was precedent to either histologic changes or elevation of hepatic enzymes and correlated with the degree of hepatic daneges in acute hepatic injury. These findings suggest that hepatic scintigraphy using Tc-GSA can be used to detect early changes and serial assessment of hepatic function in acute hepatic injury.
Animals ; Asialoglycoprotein Receptor* ; Cell Membrane ; Hepatocytes ; Inflammation ; Injections, Intraperitoneal ; Liver ; Mice* ; Necrosis ; Radionuclide Imaging* ; Serum Albumin* ; Thioacetamide*

BACKGROUND/AIMS: Tc-DTPA-galactosylated serum albumin (GSA) is a new liver imaging agent that specifically binds to asialoglycoprotein receptor, which resides exclusively on the plasma membrane of mammalian hepatocytes. To evaluate the usefulness of hepatic scintigraphy with Tc-GSA in the assessment of hepatic function, we have investigated serial changes in organ uptakes of Tc-GSA in mice with thioacetamide-induced hepatic injury and compared to changes in histology or levels of hepatic enzymes. MATERIALS AND METHODS: Acute hepatic injuries were induced by intraperitoneal injection of thioacetamide in ICR (Institute of Cancer Research) mice. Hepatic injuries were serially assessed by either light microscopic examination of liver slices or measurement of hepatic enzymes. The biodistribution of Tc-GSA was measured in liver and each excised organs using gamma counter. RESULTS: Hepatic injuries in light microscopic examination were not evident at 12 hours after injection of thioacetamide but resulted in maximal centrilobular necrosis and inflammation at 24 hours. These histologic changes were progressively improved upto 72 hours. Studied hepatic enzymes were elevated at 6 hours and reached to maximal level at 24 hours after administration of thioacetamide and declined progressively after then. Hepatic uptake of Tc-GSA was lowest at 6 hours after administration of thioacetamide and serially recovered until 72 hours. CONCLUSION: The degree in the decrease of hepatic uptake of Tc-GSA was precedent to either histologic changes or elevation of hepatic enzymes and correlated with the degree of hepatic daneges in acute hepatic injury. These findings suggest that hepatic scintigraphy using Tc-GSA can be used to detect early changes and serial assessment of hepatic function in acute hepatic injury.
Animals ; Asialoglycoprotein Receptor* ; Cell Membrane ; Hepatocytes ; Inflammation ; Injections, Intraperitoneal ; Liver ; Mice* ; Necrosis ; Radionuclide Imaging* ; Serum Albumin* ; Thioacetamide*

PURPOSE: Tc-99m labeled diethylenetriaminepentaacetic acid (DTPA) -coupled galactosylated human serum albumin (GSA) is a currently used imaging agent for asialoglycoprotein receptor (ASGPR) of the liver, but, it has several shortcomings. Recently a new ASGPR imaging agent, (99m) Tc-lactosylated human serum albumin (LSA), with simple labeling procedure, high labeling efficiency, high stability was developed. In order to assess the feasibility of the (99m) Tc-LSA as a ASGPR imaging radiopharmaceuticals, we performed biodistribution study of the tracer in liver injured mice model and the results were compared with histolgic data. MATERIALS AND METHODS: To induce hepatic damage in ICR mice, diethylnitrosamine (DEN) (60 mg/kg/week X 5 time, low dose or 180 mg/kg/week X 2 times, high dose) and thioacetamide (TAA) (50 mg/kg X 1 time) were administrated intraperitoneally. Degree of liver damage was evaluated by tissue hematoxilin-eosin stain, and expression of asialoglycoprotein receptor (ASGPR) was assessed by immunohistochemistry using ASGPR antibody. (99m) Tc-LSA was intravenously administrated via tail vein in DEN or TAA treated mice, and biodistribution study of the tracer was also performed. RESULTS: DEN treated mice showed ballooning of hepatocyte and inflammatory cell infiltration in low dose group and severe hapatocyte necrosis in high dose group, and low dose group showed higher ASGPR staining than control mice in immunohistochemical staining. TAA treated mice showed severe hepatic necrosis. (99m) Tc-LSA Biodistribution study showed that mice with hepatic necrosis induced by high dose DEN or TAA revealed higher blood activity and lower liver activity than control mice, due to slow clearance of the tracer by the liver. The degree of liver uptake was inversely correlated with the degree of histologic liver damage. But low dose DEN treated mice with mild hepatic injury showed normal blood clearance and hepatic activity, partly due to overexpression of ASGPR in mice with mild degree hepatic injury. CONCLUSION: Liver uptake of (99m) Tc-LSA was inversely correlated with degree of histologic hepatic injury in DEN and TAA treated mice. These results support that (99m) Tc-LSA can be used to evaluate the liver status in liver disease patients.
Animals ; Asialoglycoprotein Receptor ; Diethylnitrosamine* ; Hepatocytes ; Humans ; Immunohistochemistry ; Liver Diseases ; Liver* ; Mice* ; Mice, Inbred ICR ; Necrosis ; Radiopharmaceuticals ; Serum Albumin* ; Thioacetamide* ; Veins

BACKGROUNDS/AIMS: Mesenchymal stem cells (MSCs) have the capacity to differentiate into hepatocytes, The purpose of this study is to investigate the MSCs' differentiation process and therapeutic potentials by comparing isolated MSCs with HGF-treated MSCs in rat's model with thiacetamide (TAA)-induced cirrhosis. METHODS: Male Sprague-Dawley (SD) rats, weighing 100-150 g were used in this study. To induce liver fibrosis, recipient rats were taken with 0.04% thioacetamide (TAA) in the drinking water (400 mg TAA/L) for 8 weeks. The rats underlying liver cirrhosis were divided into 3 groups according to the transplanted materials, compared to normal saline as control (I) and isolated MSCs (II) HGF-treated MSCs. RESULTS: Severe hepatic fibrosis and hepatocyte destruction were detected in the control group. Less hepatic cirrhosis and collagen formation, more hepatocyte regeneration and glycogen storage were detected in isolated MSCs compared to HGF-treated MSCs group, Distribution of red autofluorescence is mainly localized near the sinusoids in isolated MSCs, scattered away the sinusoids in HGF-treated MSCs group. MSCs transdifferentiated into CK-19 postive Oval cells and then to albulmin-producing hepatocytes, HGF treated MSCs differentiated into hepatocyte without the intermediate oval cells phase. HGF treated MSCs became the CK18-positive, MSCs became CD 90-positive. CONCLUSIONS: Significant hepatocyte differentiation occurred in not HGF-treated MSCs but isolated MSCs group unexpectedly. These results suggest that the beneficial effect of MSCs on in rat's model with TAA-induced cirrhosis may occur during early differentiation course of MSCs. Mature hepatocyte itself has a little effect on the accelerated differentiation and functional capacity of hepatic lineage cell-line.
Animals ; Collagen ; Drinking Water ; Fibrosis ; Glycogen ; Hepatocytes ; Humans ; Liver ; Liver Cirrhosis ; Male ; Mesenchymal Stromal Cells ; Rats ; Regeneration ; Thioacetamide ; Transplants

AHCC (Active Hexose Correlated Compounds), which was at first extracted from cultured broth of Basidiomycotina, is known to be one of the Biological Response Modifiers (BRM). We examined the protective effects of AHCC on carbon tetrachloride (CCl4) and thioacetamide (TAA)-induced liver injury in mice. The AHCC pretreatment prevented the suppression of several physiological and biochemical parameters in the mice injected with CCl4 or TAA for 5 days. The liver weights and serum ALT and AST levels were increased by CCl4 or TAA, the degree of which was significantly reduced with the AHCC pretreatment. The AHCC pretreatment induced increasing activity of GST (glutathione s-transferase) and showed an increasing tendency of P450 and EROD (ethoxyresorufin o-dealkylation). The AHCC pretreatment also showed negative effects against the suppression of drug metabolizing enzymes, such as P450, EROD, and GST induced by CCl4 or TAA. AHCC pretreatment showed protective effects with significant inhibition of fatty change, inflammation, and necrosis in CCl4 and TAA intoxicated mice liver. The present study suggests that the protective effect of AHCC pretreatment might be related to the protection of liver from the drug induced liver injury in mice model.
Animals ; Carbon Tetrachloride ; Cytochrome P-450 CYP1A1 ; Drug-Induced Liver Injury* ; Immunologic Factors ; Inflammation ; Liver ; Mice* ; Necrosis ; Thioacetamide ; Weights and Measures