• Korean Journal of Ichthyology
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• v.12 no.3
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• pp.180-185
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• 2000

The effects of bisphenol-A(BPA), a monomer of plastics used in many consumer products, on vitellogenin(VTG) synthesis were examined in primary hepatocyte culture of olive flounder, Paralichthys olivaceus. The hepatocytes were precultured for 2 days, and then estradiol-$17\beta(10^{-6}M)$ and BPA were simultaneously added to the incubation medium. The hepatocytes were cultured for 6 more days and then spent medium was analyzed by SDS-PAGE. BPA increased the rate of VTG to total protein concentrations in a concentration-dependent way, and a significant difference was obtained at concentrations of $10^{-6}M$ and $10^{-5}M$ (P<0.05). In particular, the rate of VTG to total protein concentrations was 26.36% at $10^{-5}M$ of BPA, and its level did not differ from the control level with $E_2$ alone. $E_2$ and/or BPA-primed VTG synthesis was markedly inhibited to about 80% of the control(with $E_2$) by the addition of tamoxifen($10^{-6}M$) to the incubation medium. Furthermore, In vivo $E_2$-primed VTG synthesis was significantly inhibited by in vitro $E_2$-free incubation of hepatocyte to about 22% of the control (with $E_2$) on Day 6. The effect of reducing was delayed in a BPA concentration-dependent way. These results suggest that BPA induce VTG synthesis by estrogenic activity through estrogen receptor mediated response and prolong VTG synthesis on vitellogenesis in olive flounder.

• YAKHAK HOEJI
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• v.51 no.2
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• pp.115-125
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• 2007

The aim of this study was to investigate the protective activities of daidzin, daidzein, genistein or puerarin, active isoflavonoids of Puerariae Radix, on the hepatocyte injury induced by carbon tetrachloride (CCl$_4$, 10 mM), tert-butyl hydroperoxide (TBH, 0.5 mM) and D-galactosamine (GalN, 30 mM). Primary cultures of rat hepatocytes (18 hr cultured) were treated with CCl$_4$, TBH or GalN and various concentrations (0.1, 1, 10 and 100 ${\mu}$M) of daidzin, daidzein, genistein or puerarin. CCl$_4$ significantly increased the levels of lactate dehydrogenase (LDH), alanine aminotransferase (ALT) and aspartate aminotransferase (AST). The increase in LDH level was attenuated by daidzein, genistein and puerarin. Puerarin also inhibited the increase in AST level induced by CCl$_4$. The increases in LDH and ALT levels induced by TBH were significantly attenuated by daidzin and genistein treatments. GalN markedly increased the levels of LDH, ALT and AST These increases were significantly attenuated by daidzein. Daidzin also inhibited the increases in LDH and AST levels induced by GalN. The increases in LDH and ALT levels were attenuated by genistein and puerarin, respectively. These results suggest that daidzin and daidzein possess hepatoprotective activities.

• Preventive Nutrition and Food Science
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• v.8 no.1
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• pp.61-65
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• 2003

This study was investigated to identify the regulatory mechanism of ACC gene expression by hormones and nutrition. The fragment of ACC promoter I (PI) -220 bp region was recombined to pGL3-Basic vector with luciferase as a reporter gene. The primary hepatocyte from the rat was used to investigate the regulation of ACC PI activity. ACC PI (-220 bp)/luciferase chimeric plasmid was transfected into primary rat hepatocyte by using lipofectin. ACC PI activity was shown by measuring luciferase activity. The addition of insulin, dexamethasone, and triiodothyronine to the culture medium increased the activity of ACC PI by 2.5-, 2.3- and 1.8-fold, respectively. In the presence of 1 $\mu$M dexamethasone, the effects of insulin was amplified about 1.2-fold showing the additional effects of dexamethasone. Moreover the activity of luciferase was increased by insulin, dexamethasone, and triiodothyronine treatment approximately 4-fold. These results indicated that insulin, dexamethasone and thyroid hormone coordinately regulate ACC gene expression via regulation of promoter I activity. On the -220 to ＋21 region of ACC PI, the addition of the glucose to the culture medium increased the activity of ACC PI. With 25 mM glucose, luciferase activity increased by 7-fold. On the other hand, on the -220 bp region, ACC PI activity was not changed by polyunsaturated fatty acids. Therefore, it can be postulated that there are response elements for insulin, triiodothyronine, dexamethasone, and glucose, but not PUFAs on the -220 bp region of ACC PI.

• Archives of Pharmacal Research
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• v.21 no.6
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• pp.718-722
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• 1998

Scopoletin (7-hydroxy-6-methoxycoumarin), a coumarin, was isolated from the aerial part of Solanum lyratum Thunb. by the activity-guided fractionation employing carbon te trachloride-intoxicated primary cultured rat hepatocytes as a screening system. Its hepatoprotective activity was first evaluated by measuring the release of glutamic pyruvic transaminase and sorbitol dehydrogenase from carbon tetrachloride-intoxicated rat hepatocytes into the culture medium. Scopoletin significantly reduced the releases of glutamic pyruvic transaminase and sorbitol dehydrogenase from the carbon tetrachloride-intoxicated primary cultured rat hepatocytes by 53% and 58%, respectively, from the toxicity in a dose-dependent manner over concentration ranges of 1mcM to 50mcM. Further studies revealed that at the concentration of 10mcM, scopoletin significantly preserved glutathione content by 50% and the activity of superoxide dismutase by 36% and also inhibited the production of malondialdehyde to the degree as seen in the control.

• Toxicological Research
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• v.15 no.1
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• pp.89-93
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• 1999

2,3,7,8-Tetrachlorodibenzo-p-dioxin(TCDD) is known to induce cytochrome p450 1A1 and to activate c-Src kinase and p21 Ras. This study examined the molecular interactions of adaptor proteins including Shc, Grb2, and Sos in rat primary hepatocytes and their relationship to the induction of CYP1A1 by TCDD. TCDD induced CYP1A1 level and EROD activity in a dose-dependent mode. Sos/Grb2 association isincreased by TCDDㅑㅜ a dose dependent mode. Tyrosine phosphorylated Shc, mainly p152, onloads to Grb2/Sos complex upon TCDD stimulation. The electrophoretic mobility shift of Sos is showed by TCDD. These results indicate that TCDD modulated the molecular interaction features of adaptor compoes proteins including Shc, Grb2, and Cnl in early signaling pathway of TCDD-mediated CYP 1A1 induction of rat primary hepatocyte.

• Microbiology and Biotechnology Letters
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• v.28 no.4
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• pp.209-213
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• 2000

The cultured mycelia of Ganoderma lucidum were extracted and the extract was separated into six fractions by organic solvent fractionation. The antihepatotoxic activity of all the fractions was evaluated by measuring activities of glutamic pyruvic transaminase (GPT) and glutamic oxaloacetic transaminase (GOT). Among the fractions tested, the high-polarity fractions such as aqueous and n-butanol fractions significantly reduced activities of GPT and GOT in CCl4- and galactosamine-intoxicated rat primary hepatocytes. When intracellular synthetic activities were measured by pulsing the rate primary cultured hepatocytes with [3H]-uridine and [3H]-leucine, activities of DNA, RNA and protein. When direct toxicities of the fractions were measured against human hepatoma(SK-Hep-1), the non-polarity fractions such as n-butanol and ethyl acetate fractions showed potent direct cytotoxicities even at the concentration of 1 $\mu\textrm{g}$/ml. These data showed that Ganoderma lucidum has hepatoprotective and hepatotoxic recovery principles in its mycelia.

• Korean Journal of Ichthyology
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• v.12 no.3
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• pp.173-179
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• 2000

Effects of Estradiol-$17\beta(E_2)$ and 2, 4-dichlorophenoxy acetic acid (2, 4-D) on vitellogenin(VTG) production were investigated in primary hepatocyte culture of olive flounder, Paralichthys olivaceus. Highest survival rate of hepatocyte were observed at $27^{\circ}C$, which markedly declined equal to 50% of those of $15^{\circ}C$. Vitellogenin production peaked at the concentration of $10^{-6}M\;E_2$. No effect was observed on VTG production at various concentrations of 2, 4-D. However, a low concentration of 2, 4-D (ie, $10^{-8}M$) only appeared increased VTG production. $E_2$ or $10^{-8}M$ 2, 4-D-primed VTG production was markedly inhibited by the addition of $10^{-6}M$ tamoxifen to the culture medium(P<0.01). Inhibition was not affected by combinational treatment with $10^{-6}M$ $E_2$ and $10^{-6}M$ 2, 4-D. These results from the current investigation suggest that 2, 4-D mimics $E_2$, but the mechanism of reaction in inducing the $E_2$ receptor are different in VTG production in oliver flounder hepatocytes.

• YAKHAK HOEJI
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• v.56 no.2
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• pp.99-107
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• 2012

The protective effect of AI-1367 (Alnus japonica extract) on liver injury was investigated. Primary rat hepatocyte intoxication was induced by tert-butyl hydroperoxide (tBH), carbon tetrachloride ($CCl_4$), or D-glactosamine (D-GalN). Liver injury was induced by $CCl_4$, D-GalN or MCD (methionine choline deficient)-diet in mouse. The cellular leakage of lactate dehyrogenase and cell viability followed by the treatment of hepatotoxicants were significantly improved by AI-1367 treatment at a concentration range of 5~50 ${\mu}g/ml$ for tBH, 5~50 ${\mu}g/ml$ for D-GalN, and 5~100 ${\mu}g/ml$ for $CCl_4$, respectively. Treatment with AI-1367 (20, 10, 5 mg/kg, p.o.) on liver injury induced by subcutaneous injection of $CCl_4$ or D-GalN reduced significantly the levels of aspartate transaminase and alanine transaminase in serum. Histological observations revealed that fatty acid changes, hepatocyte necrosis and inflammatory cell infiltration in $CCl_4$ (D-GalN)-induced liver injury was improved by administration of AI-1367. AI-1367 treatment (10, 5, 2.5 mg/kg, p.o.) also significantly recovered the body weight change and serum levels of aspartate transaminase, alanine transaminase and triglyceride in liver injury induced by MCD diet. From these results, AI-1367 shows protective effects against tBH, $CCl_4$, D-GalN, or MCD diet-induced hepatotoxicity in vitro or in vivo.

• Fisheries and Aquatic Sciences
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• v.1 no.1
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• pp.19-23
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• 1998

Effects of pituitary and thyroid hormones on estradiol-induced vitellogenin (VTG) induction were electrophoretically examined in primary hepatocyte cultures of rainbow trout. Hepatocytes were precultured for 2 days and then estradiol-17 $\beta$ $(E_2,\;2 \times 10^{-6}M)$>, triiodothyronine $(T_3,\;10^{-8}-10^{-6}M)$, bovine growth hormone (bGH, 10-100 ng/ml), ovine prolactin (oPRL, 100-500 ng/ml), and pituitary extract (PE) of rainbow trout (0.75PE/dish) were added to the incubation medium. The hepatocytes were cultured for 7 more days. The addition of oPRL to the incubation medium was not effective in increasing VTG production at any concentrations. The addition of PE to the incubation medium with $E_2$ was not effective in increasing VTG production. The addition of bGH to the incubation medium with $E_2$ was not effective in increasing the rate of VTG production at concentrations of 10-50 ng/ml. However, a higher concentration of bGH, 100 ng/ml, increased VTG production. The various concentrations of $T_3$ were ineffective in stimulating VTG production. These results suggest that GH could be one of stimulus factors for VTG production in rainbow trout.

• Korean Journal of Veterinary Service
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• v.44 no.4
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• pp.299-303
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• 2021

A captive male polar bear (Ursus maritimus) was found dead after a long-term anorexia at a Park Zoo in Republic of Korea. At necropsy, the liver lesion was prominent with hepatomegaly carrying a big mass and numerous small nodules in various sizes. The cut surface of the nodules was creamy white, firm, and solid with umbilicated appearance. Histologically, there was proliferation of hepatocellular neoplastic cells arranged in glandular-like (pseudoglandular) pattern and complete loss of hepatocellular arrangement. The immunoreactivity for neoplastic hepatocyte antigens was positive for hepatocyte paraffin 1, and negative for vimentin, cytokeratin 7 and 19, and carcinoembryonic antigen. Based on those diagnostic features, the neoplasia was diagnosed as hepatocellular carcinoma. To the author's knowledge, this is the first case report of hepatocellular carcinoma in the captive polar bear in Republic of Korea.