• 한국식품과학회지
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• 제41권5호
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• pp.597-601
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• 2009

간성상세포(HSC)는 간섬유화와 간경변에 중요한 역할을 한다고 알려져 있다. 간손상에 의해 둥근 모양의 간성상세포는 활성화되어 세포외기질(ECM)을 생산하는 myofibroblast와 같은 모양으로 활성화 된다. 활성화된 간성상세포의 특징은 빠른 증식 속도와 collagen과 같은 세포외 기질의 생산이다. 활성화된 간성상 세포의 제거방법은 apoptosis를 유도하는 것이다. 가자 추출물은 정상 간세포(rat primary hepatocyte), 간세포주(HepG2) 및 활성화된 간성상세포주인 T-HSC/Cl-6에 $1,000{\mu}g/mL$의 농도까지 처리하여 세포독성을 확인하였다. 그 결과 hepatocyte나 HepG2에서는 최고 농도에서도 독성이 없었으나 T-HSC/Cl-6는 U-shape 모양으로 사멸하는 것을 확인 하였다. T-HSC/Cl-6의 사멸이 apoptosis에 의한 것인지를 Annexin-V/PI double staining을 통하여 확인한 결과 apoptosis에 의해 T-HSC/Cl-6의 사멸이 일어나는 것을 확인하였다.

• 한국발생생물학회:학술대회논문집
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• 한국발생생물학회 2005년도 제5회 발생공학 국제심포지엄 및 학술대회
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• pp.50-51
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• 2005

• 한국수정란이식학회:학술대회논문집
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• 한국수정란이식학회 2005년도 제5회 발생공학 국제심포지엄 및 학술대회
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• pp.50-51
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• 2005

• Parasites, Hosts and Diseases
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• 제48권4호
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• pp.291-295
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• 2010

The onset, severity, and ultimate outcome of malaria infection are influenced by parasite-expressed virulence factors and individual host responses to these determinants, In both humans and mice, liver injury is involved after parasite entry, which persists until the erythrocyte stage after infection with the fatal strain Plasmodium falciparum (Pf), Hepatocyte growth factor (HGF) has strong anti-apoptotic effects in various kinds of cells, and also has diverse metabolic functions. In this work, Pf-subtilisin-like protease 2 (Pf-Sub2) 5' untranslated region (UTR) was analyzed and its transcriptional activity was estimated by luciferase expression. Fourteen TATA boxes were observed but only one Oct-1 and c-Myb were done. In addition, host HGF interaction with Pf-Sub2 was evaluated by co-transfection of HGF- and Pf-Sub2-cloned vector. Interestingly, -1,422/+12 UTR exhibited the strongest luciferase activity but -329 to + 12 UTR did not exhibit luciferase activity. Moreover, as compared with the control of unexpressed HGF, the HGF protein suppressed luciferase expression driven by the 5' untranslated region of the Pf-Sub2 promoter. Taken together, it is suggested that HGF controls and interacts with the promoter region of the Pf-Sub2 gene.

• 한국환경성돌연변이발암원학회지
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• 제23권2호
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• pp.56-62
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• 2003

The liver progenitor cells could form a potential target cell population fore both tumor-initiating and -promoting chemicals. Induction of drug-metabolizing and antioxidant enzymes, including AhR-dependent CYP1A1, NQO-1 and AKR1C9, was detected in the rat liver epithelial WB-F344 "stem-like" cells. Additionally, WB-F344 cells express a functional, wild-type form of p53 protein, a biomarker of genotoxic events, and connexin 43, a basic structural unit of gap junctions forming an important type of intercellular communication. In this cellular model, two complementary assays have been established for detection of the modes of action associated with tumor promotion: inhibition of gap junctional intercellular communication (GJIC) and proliferative activity in confluent cells. We found that the PAHs and PCBs, which are AhR agonists, released WB-F344 cells from contact inhibition, increasing both DNA synthesis and cell numbers. Genotoxic effects of some PAHs that lead to apoptosis and cell cycle delay might interfere with the proliferative activity of PAHs. Contrary to that, the nongenotoxic low-molecular-weight PAHs and non-dioxin-like PCB congeners, abundant in the environment, did not significantly affect cell cycle and cell proliferation; however both groups of compounds inhibited GJIC in WB-F344 cells. The release from contact inhibiton by a mechanism that possibly involves the AhR activation, inhibition of GJIC and genotoxic events induced by environmental contaminants are three important modes of action that could play an important role in carcinogenic effects of toxic compounds. The relative potencies to inhibit GJIC, to induce AhR-mediated activity, and to release cells from contact inhibition were determined for a large series of PAHs and PCBs and their metabolites. In vitro bioassays based on detection of events on cellular level (deregulation of GJIC and/or proliferation) or determination of receptor-mediated activities in both ?$stem-like^{\circ}{\times}$ and hepatocyte-like liver cellular models are valuable tools for detection of modes of action of polyaromatic hydrocarbons. They may serve, together with concentration data, as a first step in their risk assessment.

• Parasites, Hosts and Diseases
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• 제52권2호
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• pp.151-162
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• 2014

The technique of stem cells or hepatocytes transplantation has recently improved in order to bridge the time before whole-organ liver transplantation. In the present study, unfractionated bone marrow stem cells (BMSCs) were harvested from the tibial and femoral marrow compartments of male mice, which were cultured in Dulbecco's modified Eagle's medium (DMEM) with and without hepatocyte growth factor (HGF), and then transplanted into Schistosoma mansoni- infected female mice on their 8th week post-infection. Mice were sacrificed monthly until the third month of bone marrow transplantation, serum was collected, and albumin concentration, ALT, AST, and alkaline phosphatase (ALP) activities were assayed. On the other hand, immunohistopathological and immunohistochemical changes of granuloma size and number, collagen content, and cells expressing OV-6 were detected for identification of liver fibrosis. BMSCs were shown to differentiate into hepatocyte-like cells. Serum ALT, AST, and ALP were markedly reduced in the group of mice treated with BMSCs than in the untreated control group. Also, granuloma showed a marked decrease in size and number as compared to the BMSCs untreated group. Collagen content showed marked decrease after the third month of treatment with BMSCs. On the other hand, the expression of OV-6 increased detecting the presence of newly formed hepatocytes after BMSCs treatment. BMSCs with or without HGF infusion significantly enhanced hepatic regeneration in S. mansoni-induced fibrotic liver model and have pathologic and immunohistopathologic therapeutic effects. Also, this new therapeutic trend could generate new hepatocytes to improve the overall liver functions.

• Toxicological Research
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• 제17권3호
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• pp.215-223
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• 2001

카드뮴의 주요한 표적장기이며 카드뮴이 만성 및 급성 폭로시 축적되는 가장 중요한 장기인 간의 세포독성을 Hepalclc7세포에서 caspases및 Bax단백질의 활성과 발현 그리고 미토콘드리아 세포막 전위 변화(MPT) 등을 조사하여 다음과 같은 결과를 얻었다. 1. 카드뮴은 농도의존적으로 간세포인 Hepalclc7 세포의 생존율을 감소시켰다. 2. 카드뮴을 농도별로 처리하였을 때 100 M 이상의 농도에서 세포사멸의 특징중의 하나인 DNA분절현상을 확인하였다. 3. 카드뮴 처리 후 caspase-3, caspase-8, caspase-9 의 활성변화를 조사한 결과 caspase-3,-9 pretease 활성이 시간이 경과함에 따라 증가하였다. 4. 카드뮴 처리 후 cytochrome c가 세포질내로 방출되었고 이는 caspase-9 proteas의 활성화를 유도하였다. 5. 카드뮴 처리 후 Bax가 세포질에서 미토콘드리아로 이동하여 cytochrome c의 세포질내로의 방출에 관여하였다. 6. 카드뮴 처리시 미토콘드리아 세포막 전위차의 감소를 JC-1 형광염색을 통하여 확인하였다. 이상의 결과는 카드뮴에 의한 Hepalclc7 세포사멸의 신호전달기전은 세포질내에 있는 Bax가 미토콘드리아로 이동, cytochrome c의 세포질내로의 방출, 그리고 caspase-3, 9 pretease 활성화를 의해서 매개되는 것으로 판단된다. 또한 Bax 단백질의 발현변화가 미토콘드리아의 기능변화에 기여하였으리라 사료된다.

• 한국수의병리학회지
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• 제6권1호
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• pp.41-48
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• 2002

Oval cell is considered as facultative precursor cells for both hepatocytes and biliary cells, as well as origin of hepatocellar and cholangiocellular carcinoma (CCC) during carcinogenesis or toxic liver injury. To clarify the cellular origin or differentiation of cholagiocarcinogensis, the fate of carcinogen-induced oval cells was pathologically and phenotypically chased in Syrian golden hamster liver after Clonorchis sinensis (CS) infection which would give rise to a promoting effect. Two week treatment of hamsters with 0.005% diethylnitrosamine (DEN) followed by 2 week treatment of 1% 2-acetylaminofluorene (AAF) under choline deficient diet resulted in massive proliferation of BrdU labeleed and PCNA positive oval cells showing various distinct morphology, histochemical and immunohistochemical phenotypes for GGT, cytokeratin 19 and OV-6. Oval cells also frequently form ductular-like structures or phenotypically show hepatocyte-like characteristics. After CS infection, the oval cells showed sequential morphological changes to atypicl proliferating bile ductules and all hamsters thereafter developed well differentiated and anaplastic CCC at 16 week after CS infection. In electron microscopy, some bile ductules were constructed by intermediate oval cells and bile ductular cells surrounded by basement membrane. The results of this study strongly suggest that CCC developed in the present study were originated from hepatic stem-like oval cells, supporting the theory of stem cell origin of cancers. In addition, this hamster model would be valuable for the molecular mechanistic study during chemical-triggered cholangiocarcinogenesis.

• Journal of Microbiology and Biotechnology
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• 제11권2호
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• pp.186-192
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• 2001

A primary culture of human fetal hepatocytes was obtained through a therapeutic abortion process at 26 weeks of gestation period. More than $10^8$ cells were seeded on a plastic plate. These hepatocytes were infected with hepatitis B virus (HBV). The HBV was purified from serum of one chronic HBV carrier. Transformed hepatocytes were subcultured in a 10% FBS-supplemented medium. The morphology of the transformed cell was epithelial-like. The cells from the first pass showed signs of early proliferation and had a latent period of more than 3 months after 6-7 passages. After the rest period, the transformed cell proliferated actively and they were subcultured every three days. Transformed hepatocytes were characterized by detection of the HBV transcript by RT-PCR. The secretion of virions from transformed cells was investigated by PCR with the cell medium. Two types of virions secreted into the culture medium were examined by using the transmission electron microscope. Another approach to study the secretion of virions in to culture medium was carried out with HBV antibody. HBsAg was detected in the culture medium of transformed cells using ELISA and Western blot analyses. These data suggested that the human fetal hepatocyte cell line has been established by infection of HBV, in which this cell line secreted viral particles into the culture medium.

• Asian-Australasian Journal of Animal Sciences
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• 제21권9호
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• pp.1244-1251
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• 2008

The aim of the present study was to delineate the expression and secretion of insulin-like growth factor (IGF) system components by pig liver cells. Hepatocytes were prepared from 3-wk-old weanling piglets following a two-step collagenase perfusion procedure, after which the cells were incubated for 24 or 48 h at a density of $2{\pm}10^5$ cells per 35-mm dish in 2-ml Williams' medium E. The cells were found to express the genes encoding IGF-I, IGF-binding proteins (IGFBPs)-2 and -3 and acid-labile subunit (ALS) by reverse transcription-polymerase chain reaction (RT-PCR) following the culture. However, IGF-I was localized to hepatocytes by immunohistochemical analysis, whereas IGFBP-3 was localized to endothelial cells, but not to hepatocytes. This indicated that the IGFBP-3 gene expression detected by RT-PCR was likely to have been contributed by unidentified non-parenchymal cells that had not been removed during the hepatocyte preparation. The conditioned culture medium (CCM) of the cells contained immunoreactive IGF-I and IGF-II, with the latter being seven-fold more abundant than the former. The CCM also contained 43-, 40-, 34-, 31-kDa doublet and 26-kDa IGFBPs as examined by Western ligand blotting. The 40-, 34- and 31-kDa doublet IGFBPs were approximately three-fold as abundant as the 43- and 26-kDa IGFBPs. Moreover, the 43- and 40-kDa doublet and the 34-kDa IGFBPs were immunoprecipitable with IGFBP-3 and IGFBP-2 antibodies, respectively. Overall, these results are similar to those known in the rat, which suggests that the IGF system components are likely to be expressed and secreted in pig liver in a manner similar to that in rat liver.