• The Korean Journal of Nuclear Medicine
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• v.37 no.6
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• pp.418-427
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• 2003

Objects: $^{99m}-lactosylated$ human serum albumin (LSA) is a newly synthesized radiopharmaceutical that binds to asialoglycoprotein receptors, which are specifically presented on the hepatocyte membrane. Hepatic uptake and blood clearance of LSA were evaluated in rat with acute hepatic injury induced by dimethylnitrosamine (DMN) and results were compared with corresponding findings of liver enzyme profile and these of histologic changes. Materials and Methods: DMN (27 mg/kg) was injected intraperitoneally in Sprague-Dawley rat to induce acute hepatic injury. At 3(DMN-3), 8(DMN-8), and 21 (DMN-21) days after injection of DMN, LSA injected intravenously, and dynamic images of the liver and heart were recorded for 30 minutes. Time-activity curves of the heart and liver were generated from regions of interest drawn over liver and heart area. Degree of hepatic uptake and blood clearance of LSA were evaluated with visual interpretation and semiquantitative analysis using parameters (receptor index : LHL3 and index of blood clearance : HH3), analysis of time-activity curve was also performed with curve fitting using Prism program. Results: Visual assessment of LSA images revealed decreased hepatic uptake in DMN treated rat, compared to control group. In semiquantitative analysis, LHL3 was significantly lower in DMN treated rat group than control rat group (DMN-3: 0.842, DMN-8: 0.898, DMN-21: 0.91, Control: 0.96, p<0.05), whereas HH3 was significantly higher than control rat group (DMN-3: 0.731,.DMN-8: 0.654, DMN-21: 0.604, Control: 0.473, p<0.05). AST and ALT were significantly higher in DMN-3 group than those of control group. Centrilobular necrosis and infiltration of inflammatory cells were most prominent in DMN-3 group, and were decreased over time. Conclusion: The degree of hepatic uptake of LSA was inversely correlated with liver transaminase and degree of histologic liver injury in rat with acute hepatic injury.

• Korean Journal of Clinical Laboratory Science
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• v.43 no.4
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• pp.194-204
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• 2011

This study was carried out to compare the histopathological differences of liver lesions in carbon tetrachloride ($CCI_4$), dimethylnitrosamine (DMN), thioacetamide (TAA) and bile duct ligation (BDL)-induced rats. $CCl_4$, DMN and TAA were administered intraperitoneally and conducted bile duct ligation for 4 weeks to induce hepatic fibrosis. Indices of liver cell injury (steatosis, hydropic degeneration, bile duct hyperplasia, hemorrhage & hemosiderin deposition), the extent of liver fibrosis (fibrotic area) and the rate of regeneration (number of PCNA-positive cells) were investigated in each group. Liver tissues were stained with hematoxylin-eosin (HE), sirius red, prussian blue and immunostained with ${\alpha}$-smooth muscle actin (${\alpha}$-SMA), transforming growth factor-${\beta}1$ (TGF-${\beta}1$), proliferative cell nuclear antigen (PCNA), and quantified using a computerized image analysis system. Liver cell steatosis was significantly increased in $CCl_4$ and TAA groups, and hydropic degeneration and bile duct hyperplasia were significantly increased in TAA and BDL groups when compared with that in normal control, respectively. Fibrosis area was significantly increased in all four groups, especially in $CCl_4$ group. Correlation between ${\alpha}$-SMA and TGF-${\beta}1$ expressions in four groups was good. Hemorrhage area in liver parenchyma was significantly increased in DMN group only when compared with that in normal control, while hemosiderin deposition area was significantly increased in TAA and BDL groups as well as DMN group. The Number of PCNA-positive cells was significantly increased in all four groups, especially in TAA group. These results indicate that the duration and methods of hepatotoxic drug treatment are very important factors to make plans for animal experimentation on the induction of hepatic fibrogenesis in rats.

• Archives of Pharmacal Research
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• v.25 no.5
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• pp.655-663
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• 2002

Liver fibrosis is a prepathological state wherein damaged liver tissues in chronic liver diseases, such as hepatitis, are not repaired to normal tissues, but converted to fibrous tissue. 5-(2-Pyrazinyl)-4-methyl-1,2-dithiol-3-thione (oltipraz), a cancer chemopreventive agent, is effective against a wide variety of chemical carcinogens. Recently, we reported that oltipraz inhibits liver fibrogenesis (Kang et al., 2002). In the present study, the effects of oltipraz in combination with dimethyl-4,4'-dimethoxy-5,6,5',6'-dimethylene dioxybiphenyl-2,2'-dicarboxylate (DDb) on dimethylnitrosamine (DMN)-induced liver fibrogenesis were assessed in rats. Oltipraz (30 mg/kg body weight, po, 3 times per week for 4 weeks) was found to inhibit the increases in plasma ALT, AST and bilirubin by DMN, whereas DDB (30 mg/kg body weight, po, 3 times per week for 4 weeks) attenuated the increases in the plasma ALT and bilirubin. The lowered plasma protein and albumin contents in DMN-treated rats were completely restored by oltipraz, but not by DDB. DDB decreases liver cell injury and inflammation through inhibition of nuclear factor-kB. DMN increased the accumulation of liver collagen, as indicated by the increase in the 4-hydroxyproline content in liver homogenates, which was reduced by treatment with oltipraz, but not by DDB. Given the differential effect between oltipraz and DDB, the potential enhancement of antifibrotic efficacy by the drugs was assessed in the animal model. Despite the minimal effect of DDB on DMN-induced fibrogenesis, DDB (5-25 mg/kg), administered together with oltipraz (25-5 mg/kg), showed an additive protective effect against hepatotoxicity and fibrosis induced by DMN, which was shown by the blood chemistry parameters and histopathological analysis. The adequate composition ratio of oltipraz to DDB was 5:1. These results provide information on the pharmaceutical composition, comprising of oltipraz and DDB as the active components, for the treatment and/or prevention of liver fibrosis and cirrhosis.

• Archives of Pharmacal Research
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• v.23 no.6
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• pp.613-619
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• 2000

We investigated the expression profiles of rat fibrotic liver induced by bile duct ligation and scission (BDL/S) using the 3'-directed cDNA libraries. The possibility that the 3'-directed cDNA library represents the mRNA population faithfully was examined by northern blots. During the northern analysis based on fibrotic liver expression profile, we found for the first time that purine specific sodium nucleoside cotransporter (SPNT) was upregulated in BDL/S-induced fibrotic liver. To determine whether the accumulation of bile juice could affect the expression of SPNT mRNA or not, we examined the change of SPNT mRNA expression at 3, 14, 28 days after BDL/S operation. No change in SPNT expression was observed in rat liver at 3 days after surgery. In contrast, there were significant increases in SPNT expression at 14 and 28 days after surgery. We also examined whether chronic liver damage affected SPNT mRNA expression. SPNT mRNA level was significantly increased in BDL/S-induced fibrotic rat liver, whereas no significant change was obserbed in fibrotic livers chronically exposed to carbon tetrachloride or dimethylnitrosamine. From the above results, although further study might be needed, it was considered that the increment of SPNT mRNA in BDL/S liver morphological compatibility to human was remarkable.

• Toxicological Research
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• v.17
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• pp.79-82
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• 2001

The infection of liver flukes, Clonorchis sinensis (CS) and Opisthorchis viverrini (OV), has been known as a risk factor to induce cholangiocellular carcinoma (CCC) in human living in the endemic area, providing promoting effect on the liver initiated by chemical carcinogens. The present study evaluated the relationship between the dosage level of dimethylnitrosamine (DMN) and the infection load of CS in the neoplastic development by histopathological examination of the treated hamsters. To evaluate the effects of DMN, different doses of DMN ranging from 0 to 25 ppm were administered to hamsters with 20 CS metacercariea. For the risk assessment of the infection load, 0, 5, 15, 50 CS metacercariae were respectively infected with 12 ppm DMN. The mortality was closely related to the infection load rather than the concentration of DMN. The infection of CS clearly promoted the induction of CCC even at dose level of 6 ppm DMN. Only five metacercariae were enough to promote CCC induction at the concentration of 12 ppm DMN.

• Journal of Korean Biological Nursing Science
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• v.8 no.2
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• pp.41-59
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• 2006

Chronic liver diseases and hepatic cancer have been reported as 10% of cause of death in Koreans. Regardless of various causes, chronic liver disease accompanies commonly hepatic fibrosis. But still the mechanism of hepatic fibrosis remains poorly understood. Using the dimethylnitrosamine(DMN)-induced hepatic fibrosis rat model, We performed to evaluate the possible therapeutic effect of RIP(extracts of Phellodendron amurense and Patrinia scabiosaefolia) and to investigate the changes in referential connective tissue proteins($TGF-{\beta}_1$, ${\alpha}$-smooth muscle actin, and vimentin) as a marker of fibrogenesis. For these purposes, liver tissues were stained with H & E, and Azan staining for estimation of developing fibrosis. In the DMN-treated rat liver tissue, fibrosis were developed forming incomplete septal fibrosis. Whereas, in the RIP-treated rat liver tissues, the fibrosis were decreased recovering to normal morphology. The expressions of $TGF-{\beta}_1$, ${\alpha}$-smooth muscle actin($\alpha-SMA$), and vimetin were increased in the DMN-treated rat liver tissues, but decreased in the various areas of RIP-treated rat liver tissues. According to these results, RIP could be a possible therapeutic agent to reduce hepatic fibrosis, and the $TGF-{\beta}_1$, ${\alpha}$-SMA, and vimentin could be possible indicative markers of hepatic fibrosis development and recovery.

• Biomolecules & Therapeutics
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• v.28 no.6
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• pp.527-536
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• 2020

Liver fibrosis constitutes a significant health problem worldwide due to its rapidly increasing prevalence and the absence of specific and effective treatments. Growing evidence suggests that apoptosis-signal regulating kinase 1 (ASK1) is activated in oxidative stress, which causes hepatic inflammation and apoptosis, leading to liver fibrogenesis through a mitogen-activated protein kinase (MAPK) downstream signals. In this study, we investigated whether selonsertib, a selective inhibitor of ASK1, shows therapeutic efficacy for liver fibrosis, and elucidated its mechanism of action in vivo and in vitro. As a result, selonsertib strongly suppressed the growth and proliferation of hepatic stellate cells (HSCs) and induced apoptosis by increasing Annexin V and TUNEL-positive cells. We also observed that selonsertib inhibited the ASK1/MAPK pathway, including p38 and c-Jun N-terminal kinase (JNK) in HSCs. Interestingly, dimethylnitrosamine (DMN)-induced liver fibrosis was significantly alleviated by selonsertib treatment in rats. Furthermore, selonsertib reduced collagen deposition and the expression of extracellular components such as α-smooth muscle actin (α-SMA), fibronectin, and collagen type I in vitro and in vivo. Taken together, selonsertib suppressed fibrotic response such as HSC proliferation and extracellular matrix components by blocking the ASK1/MAPK pathway. Therefore, we suggest that selonsertib may be an effective therapeutic drug for ameliorating liver fibrosis.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.15
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• pp.6279-6284
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• 2015

Opisthorchis viverrini (OV)-induced cholangiocarcinoma (CCA) is an important cancer in the Great Mekong region, particularly in Thailand. Limitations of treatment options and the lack of an effective diagnostic tool for early detection of CCA are major concerns for the control of this type of cancer. The aim of the study was to investigate anti-CCA activity of the ethanolic extract of Atractylodes lancea (Thunb.) DC., and the applicability of positron emission tomography-computed tomography (PET-CT) as a tool for detection and monitoring the progression of CCA in Opisthorchis viverrini (OV)/dimethylnitrosamine (DMN)-induced CCA hamsters. Male Syrian hamsters were used for toxicity tests and anti-CCA activity evaluation. Development of CCA was induced by initial feeding of 50 metacercariae of OV, followed by drinking water containing 12.5 ppm of DMN in hamsters. The ethanolic extract of A. lancea (Thunb.) DC. was administered orally for 30 days. PET-CT was performed every 4 weeks after initiation of CCA using 18F-fluorodeoxyglucose ($^{18}F-FDG$). Results from the present study suggest that the ethanolic extract of A. lancea (Thunb.) DC. rhizome exhibited promising anti-CCA activity and safety profile in the OV/DMN-induced hamster model. To successfully apply PET-CT as a tool for early detection of tumor development and progression, modification of radiolabeling approach is required to improve its specificity for CCA cells.

• Korean Journal of Veterinary Research
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• v.36 no.1
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• pp.169-179
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• 1996

This study was carried out to examine the role of small cells and oval cells in cholangiocarcinogenesis in the hamsters infected with Clonorchis(C) sinensis. Forty two female Syrian golden hamsters were divided into two groups. Group I was for the induction of the cholangiocarcinoma, which was infected orally with C sinensis and given dimethylnitrosamine(15ppm) in drinking water for 4 weeks. Group II was served as control. More than 5 heads of hamsters in each group were sacrificed at 4, 7, 11 and 15 weeks after the beginning of the experiment. The livers were examined histopathologically, electron microscopically and immunohistochemically. The results obtained were as follows; 1. Cholangiocarcinomas were occurred in 1 of 6 animals at 11 weeks and in 4 of 6 animals at 15weeks after the beginning of the experiment. 2. Small cells and oval cells were proliferated around the portal triads from 4 weeks and peaked at 11 weeks, and slightly decreased after then. 3. The strong positive reaction to the $\alpha$-fetoprotein was shown in many of small cells and oval cells. But ductlike oval cells, which were arranged rosette form, showed week positive reaction to the $\alpha$-fetoprotein. 4. Most of small cells and oval cells showed negative reaction to the cytokeratin. But weak positive reaction in ductlike oval cells, and moderate positive reaction in cholangiocarcinoma cells were observed. These results suggested that cholangiocarcinoma induced by infection of C sinensis was believed to originate from the proliferated small cells around the portal triads which would be able to differentiate to the oval cells, ductlike oval cells, and cholangiocarcinoma cells gradually.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.9 no.4
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• pp.223-231
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• 1976

Dimethylamine(DMA) is known as an origin compound of dimethylnitrosamine which is responsible for carcinogenesis. It has been also reported that relatively large amount of DMA is distributed in fish muscle, particularly in salted and fermented fish. Tn this experiment, the degradation products of protein and trimethylaminoxide(TMAO) by the temperature conditions of $17^{\circ}C\;and\;27^{\circ}C$ in the course of anchovy fermentation with $22\%$ of salt were analysed, and the formation of DMA was discussed. Protein-N decreased through the whole fermentation period ill the conditions of $17^{\circ}C\;and\;27^{\circ}C$ whereas amino-N increased proportionally to the decrease of protein-N, and the increasing rate of amino-N was remarkably faster at $27^{\circ}C$ than at $17^{\circ}C$. Trimethylamine(TMA) gradually increased with the decrease of TMAO till 69th day of fermentation, hereafter tended to slightly decrease. It seemed that the difference in fermentation temperature affects on the formation of DMA and obviously on the variation of TMAO. Both DMA and TMA content were inversely varied with the TMAO content. Correlation coefficient of DMA to TMAO in quantitative variation was shown -0.811 at $17^{\circ}C$ and -0.865 at $27^{\circ}C$ of fermentation temperature respectively. The results suggested that the formation of DMA during fermentation of anchovy was attributed to the degradation of TMAO showing, contributorial ratio of 0.66 at $17^{\circ}C$ and 0.75 at $27^{\circ}C$ respectively.