• Environmental Mutagens and Carcinogens
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• v.24 no.4
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• pp.171-179
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• 2004

Cytochrome P4503A4(CYP3A4) is the most abundnat CYPs in human liver, comparising approximately 30% of the total liver CYPs contents ans is involbed in the metabolism of more than 60% of currently used therapeutic drugs. The expression of CYP3A4 is induced by a variety of structurally unrelated xonobiotics including the antibiotic rifampicin and endogenous hormones, and might be mediated through steroid and xenobiotic receptor(SXR) system. The molecular mechanisms underlying regulation of CYP3A4 gene expression hae not been understood. In order to gain the insight of the molecular mechanism of CYP3A4 gene expression, study has been undertaken to investigate if the histone deacelylation is involved in the regulation of CYP3A4 gene expression by proximal promoter or not. Also SXR was investigated to see if they were involved in the regulation of CYP3A4 proximal promoter activity. HepG2 or Hena-I cells were transfected with a plasmid containing~1kb of the CYP3A4 proximal promoter region (-863 to +64bp) cloned in front of a reporter gene, luciferase, in the presence or absence of SXR or hER. Transfected cells were treated with CYP3A4 inducers such as rifampicin, PCN and RU 486, or with estradiol, in order to exmine to regulation of CYP3A4 gene expression in the presence or absence of trichostatin A (TSA). In HepG2 cells, CYP3A4 inducers and estradiol increased significantly the luciferase activity by CYP3A4 proximal promoter, only when TSA was co-treated after SXR cotransfection. In the case of Hepa-I cells CYP3A4 inducers and estradiol incressed modestly the luciferase activity when TSA was co-treated, but this increment was not enhanced by SXR cotransfection in contrast to HepG2 cells. Taken together, these results indicated that the inhibition of histone deacetylation was required to SXR-mediated increase in CYP3A4 proximal promoter region when rifampicin, or PCN was treated. Futher a trans-activation by SXR may demand other species-specific transcription factors.

• Microbiology and Biotechnology Letters
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• v.32 no.1
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• pp.67-71
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• 2004

Pata de Vaca (Bauhinia forficata) Is a tree which grows naturally in the rainforests and tropical parts of Peru and Brazil, as well as tropical zones of Asia, eastern Paraguay and northeastern Argentina. The active fraction (Pata-50) of the 70% ethanol extract from Pata de Vaca was sequentially fractionated by HP-20 Diaion column chromatography and C-18 column chromatography, and its characteristics were investigated. The growth of all cancer cells tested except for MCF-7 was Inhibited in a concentration-dependent manner by Pata-50. Its $IC_{50}$ values were estimated to be 40.4 $\mu\textrm{g}$/$m\ell$ on AGS, 51.3 $\mu\textrm{g}$/$m\ell$ on HT-29, 52.1$\mu\textrm{g}$/$m\ell$ on HepG2, 65.2$\mu\textrm{g}$/$m\ell$ on A549, and 77.5$\mu\textrm{g}$/$m\ell$ on HeLa cells. A flow cytometric analysis of HepG2 cells revealed induction of apoptosis, but cell cycle regulation was not affected. The HepG2 cell population of apoptosis region increased In a concentration-dependent manner by Pata-50.

• Nuclear Medicine and Molecular Imaging
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• v.41 no.3
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• pp.226-233
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• 2007

Purpose: Dual reporter gene imaging has several advantages for more sophisticated molecular imaging studies such as gene therapy monitoring. Herein, we have constructed hepatoma cell line expressing dual reporter genes of sodium iodide symporter (NIS) and enhanced green fluorescence protein (EGFP), and the functionalities of the genes were evaluated in vivo by nuclear and optical imaging. Materials and Methods: A pRetro-PN vector was constructed after separating NIS gene from pcDNA-NIS. RSV-EGFP-WPRE fragment separated from pLNRGW was cloned into pRetro-PN vector. The final vector expressing dual reporter genes was named pRetro-PNRGW. A human hepatoma (HepG2) cells were transfected by the retrovirus containing NIS and EGFP gene (HepG2-NE). Expression of NIS gene was confirmed by RT-PCR, radioiodine uptake and efflux studies. Expression of EGFP was confirmed by RT-PCR and fluorescence microscope. The HepG2 and HepG2-NE cells were implanted in shoulder and hindlimb of nude mice, then fluorescence image, gamma camera image and I-124 microPET image were undertaken. Results: The HepG2-NE cell was successfully constructed. RT-PCR showed NIS and EGFP mRNA expression. About 50% of cells showed fluorescence. The iodine uptake of NIS-expressed cells was about 9 times higher than control. In efflux study, $T_{1/2}$ of HepG2-NE cells was 9 min. HepG2-NE xenograft showed high signal-to-background fluorescent spots and higher iodine-uptake compared to those of HepG2 xenograft. Conclusion: A hepatoma cell line expressing NIS and EGFP dual reporter genes was successfully constructed and could be used as a potential either by therapeutic gene or imaging reporter gene.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.245.2-246
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• 2002

We studied on the antiproliferative effects of bile acids and their derivatives on HepG2 human hepatocellular carcinoma cells. Ursodeoxycholic acid (UDCA) and its synthetic derivative HS-1030. and chenodeoxycholic acid (CDCA) and its synthetic derivatives. HS-1199 and HS\ulcorner200, were used. We focused on the regulation of cell cycle and induction of apoptosis by these bile acid derivatives. (omitted)

• Journal of Ginseng Research
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• v.47 no.3
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• pp.420-428
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• 2023

Background: Ginsenoside F2 (GF2), a minor component of Panax ginseng, has been reported to possess a wide variety of pharmacological activities. However, its effects on glucose metabolism have not yet been reported. Here, we investigated the underlying signaling pathways involved in its effects on hepatic glucose. Methods: HepG2 cells were used to establish insulin-resistant (IR) model and treated with GF2. Cell viability and glucose uptake-related genes were also examined by real-time PCR and immunoblots. Results: Cell viability assays showed that GF2 up to 50 μM did not affect normal and IR-HepG2 cell viability. GF2 reduced oxidative stress by inhibiting phosphorylation of the mitogen-activated protein kinases (MAPK) signaling components such as c-Jun N-terminal kinase (JNK), extracellular signal-regulated kinase 1/2 (ERK1/2), and p38 MAPK, and reducing the nuclear translocation of NF-κB. Furthermore, GF2 activated PI3K/AKT signaling, upregulated the levels of glucose transporter 2 (GLUT-2) and GLUT-4 in IR-HepG2 cells, and promoted glucose absorption. At the same time, GF2 reduced phosphoenolpyruvate carboxykinase and glucose-6-phosphatase expression as well as inhibiting gluconeogenesis. Conclusion: Overall, GF2 improved glucose metabolism disorders by reducing cellular oxidative stress in IR-HepG2 cells via MAPK signaling, participating in the PI3K/AKT/GSK-3β signaling pathway, promoting glycogen synthesis, and inhibiting gluconeogenesis.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.4
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• pp.586-590
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• 2003

The pharmacological effect of Korean-Chinese traditional herbal medicine, Hawangyeonhaedoktang (HT) on experimentally induced-triglyceride accumulation in cultured human hepatocyte HepG2 cells was studied. HePG2 cells were cultured in the Dulbecco's modified Eagle's (DME) medium without (Control medium) or with HT (0.5 mg/mL and 5.0 mg/mL) containing 1 mM oleate, 0.2% bovine serum albumin (BSA), and glucose 4.5 mg/mL for 6 and 24 hours in experiment I and 2 mM oleate, 0.5% BSA, and glucose 4.5 mg/mL for 6, 24 and in hours in Experiment II or 1 and 3 hours in Experiment III. Oleate ［$^{14}$ C］(0.5 $\mu$Ci/mL medium) added as a radioactive lipid precursor in the experiment I. In the experiment I, the intracellular triglyceride concentration was decreased remarkably during incubation for 6 and 24 hours, in a dose-dependent manner. At the same time, HT caused a decrease in the incorporation of ［$^{14}$ C］ oleate into intracellular triglyceride fraction and the secretion of triglyceride labeled with ［$^{14}$ C］ oleate into medium. In the experiment II and III compared to experiment I, the triglyceride accumulation in HepG2 cells was occurred, and HT prevented the accumulation of triglyceride during incubation for 24 and 48 hours. This result suggest that HT prevent the triglyceride accumulation in human hepatocytes by its inhibiting action on the intercellular triglyceride biosynthesis.

• Herbal Formula Science
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• v.15 no.1
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• pp.213-228
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• 2007

Objectives : The purpose of this report was to investigate the chemotherapeutic effect of Bujeonghangamtang against cancer cells. Materials and Methods : Various cancer cell lines including PANC-1, C6 glioma, SH-SY5Y, HepG2, and MCF-7 cells, were used. Apoptosis was determined by DAPI nuclei staining and flow cytometry in PANC-1 cells treated with 1 mg/ml Bujeonghangamtang for 48 hr. Expression of cell cycle arrest mediators including, cdc2p34 and cyclin B1 proteins were measured by Western blot analysis. Mitochondrial membrane potential was measured by fluorescence staining with JC-1, rhodamine 123. Result : Bujeonghangamtang induced the apoptosis of PANC-1, which was characterized as nucleic acid and genomic DNA fragmentation, chromatin condensation, and sub-G0/G1 fraction of cell cycle increase. but not C6 glioma, SH-SY5Y, HepG2, and MCF-7 cells. PANC-1 cells were markedly sensitive to Bujeonghangamtang. Treatment with Bujeonghangamtang resulted in the decreased expression of cdc2p34 and cyclin B1. Treatment with Bujeonghangamtang also increased the ROS production and induced mitochondrial dysfunction. Conclusion : Bujeonghangamtang exerted cytotoxicity against human Pancreatic cancer cells via cell cycle arrest-mediated apoptotic signaling including ROS production and mitochondrial dysfunction. Our data suggest that Bujeonghangamtang may be an important modulator of chemosensitivity of cancer cells against anticancer chemotherapeutic agents.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.6
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• pp.931-936
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• 2003

We investigated inhibitory effects of Hericium erinaceus on the growth of cancer cells and the expression of cell cycle regulators, cyclins. Anticancer effects of Hericium erinaceus extract and fractions against cancer cell lines including HepG2 and HT29 were investigated. The methanol extract, the hexane fraction, the chloroform fraction and the ethylacetate fraction of Hericiu erinacew inhibited growth of cancer cells but they had no effect on the cytotoxicity of normal human liver cells under the same conditions. As shown by western blot analysis, the expression of cyclin B1 known as cell cycle regulator was markedly decreased after treatment with Hericium erinaceus extract in HepG2 cells. These results suggest that antiproliferative effect of Hericaum erinaceus extract is associated with markedly decreased expression of cyclin B1.

• Journal of the East Asian Society of Dietary Life
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• v.19 no.3
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• pp.384-394
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• 2009

This study was performed to determine the antioxidative and anticancer effects of extracts from Adenophora remotiflora leaves. The antioxidative effects of the extracts were measured using 1,1-diphenyl-2-picrylhydrazyl (DPPH)-radical scavenging activity and hemoglobin-induced linoleic acid oxidative inhibition assays. The results indicated that the extracts had stronger effects than the synthetic antioxidant BHT at the same concentration. The $SC_{50}$ values (50% radical scavenging effect on $1{\times}10^{-4}$ M DPPH) of the methanol fraction, water extract, and BHT were 47.5 ${\mu}g$/mL, 74.6 ${\mu}g$/mL and 102.2 ${\mu}g$/mL, respectively. In addition the $IC_{50}$ values (hemoglobin-induced linoleic acid oxidation inhibition) of the methanol fraction, water extract, and BHT were 120.8 ${\mu}g$/mL, 135.6 ${\mu}g$/mL, and 150.2 ${\mu}g$/mL, respectively. This research also assessed decreases in the survival of BNLcl2 cells (normal liver cells) by solvent fractions of the A. remotiflora leaf extracts at various concentrations (1, 5, 10, 25, 50, 100, 250, 500, 1,000, 2,000 ${\mu}g$/mL). The water extract did not decrease survival at any of the concentrations when compared to the control group. The hexane, ethyl acetate, and methanol fractions decreased survival as compared to the control group by inducing cell toxicity at a concentration of 1,000 ${\mu}g$/mL and above. Therefore, an anticancer activity experiment was conducted using concentrations below 500 ${\mu}g$/mL. At 500 ${\mu}g$/mL, the methanol fraction decreased A549 cell (human lung carcinoma cells) survival by 46% as compared to the control group, presenting the greatest effect against cell survival. All extracts showed greater anticancer activity in Hep G2 cells (human liver carcinoma cells) as compared to the A549 cells. For the Hep G2 cells, the methanol extract decreased survival by 28% as compared to the control group at the concentration of 500 ${\mu}g$/mL, thus restraining lung cancer cell growth.

• The Journal of Korean Medicine
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• v.20 no.1 s.37
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• pp.91-105
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• 1999

The effects of Yinjin and Yinjinsaryongsangagambang on a DNA damaging agent, etoposide-induced apoptosis, cell viability, cell cycle progression, and mRNA expression of apoptosis-related genes of human hepatocyte cell line HepG2 were investigated using tryphan blue exclusion assay, MTT assay, flow cytometry, immunocytometric analysis of PCNA, and quantitative RT-PCR analysis. MTT assay showed that Yinjin and Yinjinsaryongsangagambang increases cellular viability of HepG2 cells in a dosage-dependent manner. Stimulation of cell cycle progression by Yinjin or Yinjinsaryongsangagambang was detected by flow cytometric analysis of the DNA content and immunocytometric analysis of PCNA expression. A significant reduction of a DNA-damaging agent, etoposide-induced apoptosis were found in both Yinjin and Yinjinsaryongsangagambang-treated cells in dosage-dependent manner. In overall, 3-fold reduction of apoptosis was recognized in $10.0\;{\mu}g/ml$ of Yinjin or Yinjinsaryongsangagambang-treated cells compared to untreated cells. Although the difference is not significant, Yinjinsaryongsangagambang showed slightly higher effect on the inhibition of apoptosis than Yinjin. From flow cytometric analysis of apoptosis, while 39.9% of untreated cells showed etoposide-induced apoptotic cell death, only 19.6% or 17.4% of Yinjin or Yinjinsaryongsangagambang-treated cells were fond at apoptotic sub G1 phase, respectively. Interestingly, strong induction of Gadd45-mRNA was observed from Yinjin or Yinjinsaryongsangagambang-treated cells. However, no changes in expression levels of p53 and Waf1 were detected, demonstrating that induction of Gadd45 mRNA expression by Yinjin or Yinjinsaryongsangagambang occurs by p53-independent mechanism. Marked mRNA inductions of two apoptosis-inhibiting genes, Bcl-2 and Bcl- XL, were found in both Yinjin or Yinjinsaryongsangagambang-treated HepG2 cells while no changes was detected in expression levels of an apoptosis-promoting gene, Bax.