• Toxicological Research
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• 제3권1호
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• pp.1-8
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• 1987

In vitro induction of cytochrome 450 associated monooxygenase activities by phenobarbital (PB) and 3-methylcholanthrene (MC) was investigated in primary cultures of adult rat hepatocytes. PB and MC were added to the culture 24 hr after the initial plating of hepatocytes. A signiftcant increase of the activities of 7-ethoxycoumarin 0-deethylase and aryl hydrocarbon hydroxylase were observed in MC and PB treated culture. MC caused about 500% induction of the initial oxidation rates of both enzymes in 48 hr. However the PB maintained both enzyme activities close to the level of freshly isolated hepatocytes. Biphenyl 4-hydroxylase and aminopyrine N-demethylase activities were also induced by MC and PB. But the level of induction was less than that occuring with 7-ethoxycoumarin 0-deethylase and aryl hydrocarbon hydroxylase. When aflatoxin $B_1$ was added to the hepatocyte cultures which have been treated with MC or PB, it caused a significant increase of the unscheduled DNA synthesis at higher dose of aflatoxin $B_1$ as compared to those of untreated control hepatocyte cultures. The results suggest that microsomal enzyme activities can be selectively controlled preferably in hepatocyte cultures by the in vitro induction method. This principle may be useful for studying the metabolism and other toxicological studies.

• Nutritional Sciences
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• 제8권4호
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• pp.212-218
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• 2005

Hepatoprotective effects of the extract of Kochiae fructus (KF), a traditional oriental medicinal plant, were evaluated against carbon tetrachloride($CCl_4$)-induced liver damage in rats. Male Sprague-Dawley rats were divided into control, $CCl_4,\;CCl_4$ plus methanol extract of KF (KFM-$CCl_4$), and $CCl_4$ plus butanol extract of KF (KFB-$CCl_4$) groups. KFM and KFB were orally administered once a day (200 mg/kg body weight) for 14 days. A mixture of 0.2 mL/100 g body weight of $CCl_4$ in olive oil was injected at 30 minutes after the final administration of KFM and KFB. The KFB pretreatment resulted in a significant decrease in the serum transaminase and lactic dehydrogenase levels in the $CCl_4$-treated rats. The $CCl_4$ treatment significantly lowered the activities of glutathione, glutathione reductase (GR), glutathione-S-transferase (GST), superoxide dismutase (SOD), catalase and glutathione peroxidase (GSH-Px). However, pretreatment with KFM and KFB resulted in a significant increase in the glutathione, GR and GST levels. KFB increased the activities of SOD, catalase and GSH-Px, but KFM did not alter them. Pretreatment with KFM and KFB resulted in a significant decrease in the production of aminopyrine N-demethylase in the $CCl_4$-treated rats. KF extract would appear to contribute to alleviate the adveISe effect of $CCl_4$ treatment by enhancing the hepatic antioxidant defense system.

• Clinical and Experimental Pediatrics
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• 제56권8호
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• pp.355-358
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• 2013

Kabuki syndrome (KS) is a rare genetic disease with a distinctive dysmorphic face, intellectual disability, and multiple congenital abnormalities. KS is inherited in an autosomal dominant manner. As the primary cause of KS, MLL2 mutations have been identified in 56-76% of affected individuals who have been tested, suggesting that there may be additional genes associated with KS. Recently, a few KS individuals have been found to have de novo partial or complete deletions of an X chromosome gene, KDM6A, which encodes a histone demethylase that interacts with MLL2. Nevertheless, mutations in MLL2 are the major cause of KS. Although there are a few reports of KS patients in Korea, none of these had been confirmed by genetic analysis. Here, we report a case of a Korean patient with clinical features of KS. Using direct sequencing, we identified a frameshift heterozygous mutation for MLL2 : (c.5256_5257delGA;p.Lys1753Alafs$^*34$). Clinically, the patient presented with typical facial features, and diagnosis of KS was based on the diagnostic criteria. While KS is a rare disease, other malformations that overlap with those found in individuals with KS are common. Hence, the diagnosis of KS by mutational analysis can be a valuable method for patients with KS-like syndromes. Furthermore, in the near future, other genes could be identified in patients with KS without a detectable MLL2 mutation.

• Journal of Nutrition and Health
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• 제38권9호
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• pp.689-697
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• 2005

This study was conducted to fine out the preventive effects of chitosan and chitosan oligomer on the disorders of hepatic functions and lipid metabolism induced by 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin (TCDD) using adult male rats (SD) for four weeks. Rats were fed chitosan ($4\%$) or chitosan oligomer ($4\%$) diets respectively before 3weeks of TCDD treatment (50 ug/kg BW) by intraperitoneal injection and then continually supplied these diets for one week until being sacrificed. The elevation of serum total and LDL cholesterol levels induced by TCDD treatment was significantly reduced in the rats fed chitosan diets. The increment of liver triglyceride levels caused by TCDD treatment was tended to suppress in all rats fed chitosan and chitosan oligomer diets. Fecal total lipid and cholesterol excretion were high levels in the rats fed chitosan diets. The hepatic cytosolic catalase activities significantly decreased by TCDD treatment appeared recovering trend by chitosan diets. In hepatic microsomal cytochrome p-450, NADPH cytochrome p-450 reductase, ethoxycoumarin-o-deethylase (ECOD) and benzphetamin N-demethylase (BPND) chitosan than chitosan oligomer diets apparently decreased the increasing levels by TCDD treatment. In histochemical observation the fat droplets and apoptosis of hepatocytes by TCDD treatment were markedly alleviated by chitosan and chitosan oligomer diets. These results indicate that chitosan, more than chitosan oligomer can exert preventive effects on some disorders of hepatic functions and lipids accumulation by TCDD.

• 약학회지
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• 제52권4호
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• pp.316-321
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• 2008

The hepatoprotection by the methanol extract of Oenanthe javanica DC (water dropwort) (OJME) was investigated in Sprague Dawley rats with inducing liver damage by acetaminophen. After OJME administration for 1 week, the increase of hepatic lipid peroxide level by acetaminophen-induced hepatotoxicity was significantly reduced. In case of phase I microsomal enzyme systems including cytochrome P-450, aminopyrine N-demethylase and aniline hydroxylase, any significant differences between in control and in OJME-pretreated group was observed after acetaminophen treatment. However, the pretreatment of OJME maintained the hepatic glutathione level and the activity of liver cytosolic glutathione S-transferase, which was significantly decreased by the acetaminophen intoxication. Among the glutathione-generating system, glutathione reductase was more responsible for its biosynthesis rather than ${\gamma}-glutamylcystein$ synthetase. OJME itself showed the strong inhibition activity on DPPH radical generation. In conclusion, OJME administration maintains the liver glutathione pool and hepatic glutathione S-transferase activity, in addition with its high anti-oxidative capability, to show hepatoprotective effect from acetaminophen intoxication.

• 동의생리병리학회지
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• 제17권5호
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• pp.1177-1181
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• 2003

Chinese cabbage is a vegetable of Cruciferous family. It was usually consumed as Kimchi. It was known to have amount of vitamin c. Recently the trend for the development of functional food combined with oriental herbs. For this aim the study was performed to evaluate the hepatoprotective effect via antioxidant activity of leaf and root of Sanchon Chinese cabbage(Brassica campetris L.) comparatively. The methanol extracts of Chinese cabbage were tested for investigating the effects on the formation of lipid peroxide and the activities of free radical generating enzyme in vitro in bromobenzene-treated rats. The methanol extracts of chinese cabbage reduced bromobenzene-induced hepatic lipid peroxidation and inhibited the activity of xanthine oxidase. The methanol extracts of chinese cabbage did not activate amionopyrine N-demethylase, aniline hydroxylase and glutathione S-transferase. Epoxide hydrolase activity was decreased by bromobenzene, which was restored by pretreatment of the methanol extracts of chinese cabbage. The results suggest that the methanol extracts of Chinese cabbage is reduced by enhancing the activity of epoxide hydrolase.

• 한국연초학회지
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• 제20권1호
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• pp.99-107
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• 1998

Numerous studies have demonstrated a negative association between cigarette smoking and Parkinson's disease. The present study was undertaken to investigate whether chronic exposure of mice to cigarette smoke a(footed the metabolism of 1-methyl-1113,6-tetrahydro-pyridine (MPTP) by cytochrome P4SO (P-450) or flavin-containing monooxygenase (FMO) in the hepatic microsomes of C57BL6/J mice. Adult male C57BL6/J mice were exposed to mainstream smoke generated from 15 cigarettes for 10 min a day and 5 day per week for 6 weeks. MPTP (10 mg/kg body weight) was administered to mice by subcutaneous injection for 6 consecutive days. Microsolnal P-450 content was increased by MPTP, smoke exposure, or both, but NADPH cytochrome P-450 reductase activity was rather decreased by the same treatments. The activities of benzo(a)pyrene hydroxylase, 7-ethoxycoumarin O-deethylase and ethoxyresorufin O-deethylase were significantly increased by the exposure of cigarette smoke, but were not or little affected by MPTP treatment. Benzphetamine N-demethylase activity was not affected either by MPTP treatment or by cigarette smoke exposure, but it was significantly increased by the combined MPTP treatment with cigarette smoke exposure, showing their synergic effect for the induction of the enzyme activity. Interestingly, in vitro studies of hepatic FMO and P-450 system both O-oxygenation and N-demethylation of MPTP were increased in the smoke-exposed or in the MPTP-treated mice. These results suggest that the enhancement in the N-demethylation as well as O-deethylation of P-450 system and in the N-oxygenation of FMO activity by cigarette smoke exposure in mouse liver may contribute to attenuating the neurotoxic effects of MPTP on the nigrostriatal dopaminergic neurons.

• Asian Pacific Journal of Cancer Prevention
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• 제15권7호
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• pp.3051-3056
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• 2014

Previous studies have demonstrated that JMJD2A is a potential oncogene and is overexpressed in human tumors. However, its role in the endometrial carcinoma remains largely unknown. In this study, we discovered that JMJD2A was overexpressed in endometrial carcinoma, using immunohistochemistry, quantitative realtime polymerase chain reaction, and western blotting. Downregulation of JMJD2A led to reduced endometrial carcinoma RL95-2 and ISK cell proliferation, invasion and metastasis as asessed with cell counting kit-8, cell migration and invasive assays. Collectively, our results support that JMJD2A is a promoter of endometrial carcinoma cell proliferation and survival, and is a potential novel drug target.

• BMB Reports
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• 제49권5호
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• pp.245-246
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• 2016

The level and activity of critical regulatory proteins in cells are tightly controlled by several tiers of post-translational modifications. HIF-1α is maintained at low levels under normoxia conditions by the collaboration between PHD proteins and the VHL-containing E3 ubiquitin ligase complex. We recently identified a new physiologically relevant mechanism that regulates HIF-1α stability in the nucleus in response to cellular oxygen levels. This mechanism is based on the collaboration between the SET7/9 methyltransferase and the LSD1 demethylase. SET7/9 adds a methyl group to HIF-1α, which triggers degradation of the protein by the ubiquitin-proteasome system, whereas LSD1 removes the methyl group, leading to stabilization of HIF-1α under hypoxia conditions. In cells from knock-in mice with a mutation preventing HIF-1α methylation (Hif1α^KA/KA), HIF-1α levels were increased in both normoxic and hypoxic conditions. Hif1α^KA/KA knock-in mice displayed increased hematological parameters, such as red blood cell count and hemoglobin concentration. They also displayed pathological phenotypes; retinal and tumor-associated angiogenesis as well as tumor growth were increased in Hif1α^KA/KA knock-in mice. Certain human cancer cells exhibit mutations that cause defects in HIF-1α methylation. In summary, this newly identified methylation-based regulation of HIF-1α stability constitutes another layer of regulation that is independent of previously identified mechanisms.

• 생약학회지
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• 제36권2호통권141호
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• pp.81-87
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• 2005

The effects of the DWP-04 [DDB:selenium yeast:glutathione (31.1 : 6.8 : 62.1 (w/w%)] on acetaminophen detoxification enzyme system were studied in rats. Treatment with DWP-04 was prevented againt acetaminophen-induiced hepatotoxicity in rat as evidenced by the decreased formation of lipid peroxide. Effect of DWP-04 on the activities of free radical-generating enzymes, free radical scavenging enzymes and glutathione-related enzymes as well as detoxification mechanism of DWP-04 against acetaminophen-treated was investigated in rat. Activities of cytochrome p450, cytochrome b5, aminopyrine demethylase and aniline hydroxylase as free radical-generating enzymes activities were decreased by the treatment with DWP-04 against acetaminophen treated. Although acetaminophen-induced hepatotoxicity results in the significantly decrease in the level of hepatic glutathione and activities of glutathine S-transferase, quinone reductase, glutathione reductase and ${\gamma}-glutamyl-$cysteine synthetase, these decreasing effects were markedly lowered in the DWP-04-treated rat. Therefore, it was concluded that the mechanism for the observed preventive effect of DWP-04 against the acetaminophen-induced hepatotoxicity was associated with the decreased activities in the free radical-generating enzyme system.