• The Korean Journal of Pharmacology
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• v.29 no.2
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• pp.275-282
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• 1993

Liver microsomal epoxide hydrolase (mEH) is active in the detoxification of epoxide-containing reactive intermediate. Previous studies in this laboratory have shown that thiazole and pyrazine are efficacious inducers of mEH in rats with large increases in mEH mRNA levels (Carcinogensis, Kim et al, 1993). mEH was purified to electrophoretic homogeneity from thiazole-induced rat hepatic microsomes using DEAE-cellulose column chromatography whereas another protein $({\sim}43\;kDa)$ was co-purified with mEH from pyrazine-induced rat hepatic micrsomes (200 mg/kg body weight/day, ip, 3d). The antibody raised from a rabbit against mEH protein purified from thiazole-induced rat hepatic microsomes appeared to specifically recognize mEH protein in rat hepatic microsomes, as assessed by immunoblotting analysis. Immunoblotting analyses revealed a 10- and 7-fold increase in mEH levels in the hepatic microsomes isolated from thiazole- and pyrazine-treated rats, respectively. Moreover, immunoblotting analysis showed cross-reactivity of the mEH antibody with a 43 kDa protein in pyrazine-induced rat hepatic microsomes and with co-purified 43 kDa protein in purified fractions. The ratio between the 43 kDa protein and mEH in pyrazine-induced rat microsomes or in purified fractions was ${\sim}1$ to 15. N-terminal amino acid sequence analysis of both purified rat mEH and 43 kDa protein revealed that 10 out of 12 amino acids in N-terminus of the 43 kDa protein were identical with the mEH sequence with two amino acid residues of the 43 kDa protein undetermined. Either thiazole or pyrazine treatment, however, failed to increase the levels of mEH protein in rabbits while pyrazine caused elevation of the 43 kDa protein in this species, as determined by irnrnunoblotting analysis. These results demonstrated that treatment of rats with either thiazole or pyrazine causes elevation in hepatic mEH expiession whereas pyrazine treatment results in induction of another mEH-related 43 kDa protein and that a distinct species difference exists between rats and rabbits in the induction of mEH by these xenobiotics.

• Microbiology and Biotechnology Letters
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• v.34 no.2
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• pp.129-135
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• 2006

A gene encoding for a putative microsomal epoxide hydrolase (mEH) of a zebrafish, Danio rerio, was cloned and characterized. The putative mEH protein of D. rerio exhibited sequence similarity with mammalian mEH and some other bacterial EHs. A structural model for the putative mEH was constructed using homology modeling based on the crystallographic templates, 1 qo7 and 1 ehy. The catalytic triad consisting of $Asp^{233}$, $Glu^{413}$, and $His^{440}$ was identified, and the characteristic features such as two tyrosine residues and oxyanion hole were found to be highly conserved. Based on bioinformatic analysis together with EH activity assay, the putative protein was annotated as mEH of D. rerio. Enantiopure styrene oxide with enantiopurity of 99%ee and yield of 33.5% was obtained from racemic styrene oxide by the enantioselective hydrolysis activity of recombinant mEH of D. rerio for 45 min.

• KSBB Journal
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• v.19 no.1
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• pp.42-49
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• 2004

A gene coding for epoxide hydrolase (EH) of Aspergillus niger LK, a fungus possessing the enantioselective hydrolysis activity for racemic epoxides, was characterized by phylogenetic analysis. The deduced protein of A. niger LK epoxide hydrolase shares significant sequence similarity with several bacterial EHs and mammalian microsomal EHs (mEH) and belongs to the a/${\beta}$ hydrolase fold family. EH from A. niger LK had 90.6% identity with 3D crystal structure of lqo7 in Protein Data Bank. Sequence comparison with other source EHs suggested that Asp$\^$l92/, Asp$\^$374/ and His$\^$374/ constituted the catalytic triad. Based on the multiple sequence comparison of the functional and structural domain sequence, the phylogenetic tree between relevant epoxide hydrolases from various species were reconstructed by using Neighbor-Joining method. Genetic distances were so far as 1.841-2.682 but characteristic oxyanion hole and catalytic triad were highly conserved, which means they have diverged from a common ancestor.

• YAKHAK HOEJI
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• v.51 no.5
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• pp.291-295
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• 2007

The present study examines the effect of dominant-negative Akt on the insulin-mediated microsomal epoxide hydrolase (mEH) induction in rat hepatocytes. We also assessed the role of insulin in the expression of soluble epoxide hydrrolase (sEH). Insulin increased mEH levels and the enzyme activities, whereas sEH protein expression was unaffected by insulin. The specific PI3K inhibitors or p70 S6 kinase inhibitor ameliorated the insulin-mediated increase in mEH protein levels. Infection with adenovirus expressing dominant-negative and kinase-dead mutant of Akt1 effectively inhibited the insulin-mediated increase in mEH expression and mEH activity. These results suggest that mEH and sEH are differentially regulated by insulin and PI3K/Akt/p70S6K are active in the insulin-mediated regulation of mEH expression.

• The Korean Journal of Pharmacology
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• v.32 no.2
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• pp.233-241
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• 1996

Previous studies have shown that glucocorticoid suppresses microsomal epoxide hydrolase(EH) gene expression and that EH expression is altered during pregnancy. The effects of progesterone on the expression of rat EH and certain glutathione S-transferase(GST) genes were examined in this study. Northern RNA blot analysis revealed that progesterone was effective in increasing hepatic EH mRNA levels at 12 h to 48 h after treatment with a maximal 9-fold increase being noted at 12 h time point. Nonetheless, multiple daily treatment with progesterone rather caused minimal relative increases in EH mRNA levels. GST Ya and Yb1/2 mRNA levels were also transiently elevated at 12 h after progesterone treatment, followed by gradual decreases from the maximal Increases at day 1, 2 and 5 post-treatment. These changes in EH and GST mRNA levels were noted only at a relatively high dose of progesterone. Furthermore, immunoblot analyses showed that rats treated with progesterone for 5 days failed to show EH or GST induction, indicating that progesterone-induced alterations in EH and GST mRNA levels do not reflect bona fide induction of the detoxifying enzymes. Concomitant progesterone treatment of rats with the known EH inducers including ketoconazole and clotrimazole failed to additively nor antagonistically alter EH mRNA levels. In contrast, dexamethasone substantially reduced ketoconazole- or clotrimazole-inducible EH expression. These results showed that progesterone stimulates the EH, GST Ya and Yb1/2 gene expression at early times followed by marked reduction in the RNA levels from the maximum after multiple treatment and that the changes in mRNA do not necessarily reflect induction of the proteins.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.2
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• pp.521-525
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• 2012

Microsomal epoxide hydrolase (mEH) plays a significant role in the metabolism of numerous xenobiotics and is associated with several forms of cancer. Here, we investigated the role of mEH expression in bladder carcinogenesis, subsequent progression and recurrence. The expression of mEH was analyzed by Western blot in 50 bladder urothelial carcinoma and 20 normal epithelial tissues. There was a significantly higher mEH expression in the normal epithelium (P<0.05) and mEH expression was lower in high stage than in low stage tumors (P<0.05). Further, immunohistochmistry in 106 bladder urothelial carcinoma demonstrated mEH expression to be negatively correlated with histological grade, pT stage and recurrence (P<0.05). These findings suggest the important role of mEH in bladder carcinogenesis, cancer development and recurrence, providing support for efforts to develop mEH-based gene therapy.

• Food Science of Animal Resources
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• v.37 no.4
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• pp.599-605
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• 2017

Korean native honey (KNH) is much more expensive than European honey (EH) in Korea, because KNH is a favored honey which is produced less than EH. Food fraud of KNH has drawn attention of the government office concerned, which is in need of a method to differentiate between KNH and EH which are produced by the Asiatic honeybee, Apis cerana and the European honeybee, Apis mellifera, respectively. A method to discriminate KNH and EH was established by using duplex polymerase chain reaction (PCR) in this study. Immunochromatographic assay (IC) was examined to analyze the duplex PCR product. The DNA sequences of primers for the duplex PCR were determined by comparing cytochrome C oxidase genes of the two honey bee species. Chelex resin method was more efficient in extracting genomic DNA from honey than the other two procedures of commercial kits. The duplex PCR amplifying DNA of 133 bp were more sensitive than that amplifying DNA of 206 bp in detecting EH in the honey mixture of KNH and EH. Agarose gel electrophoresis and IC detected the DNA of 133 bp at the ratios of down to 1% and 5% EH in the honey mixture, respectively and also revealed that several KNH products distributed by internet shopping sites were actually EH. In conclusion, the duplex PCR with subsequent IC could also discriminate between KNH and EH and save time and labor.

• Journal of the Society of Naval Architects of Korea
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• v.51 no.1
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• pp.26-33
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• 2014

In this study, Non-load-carrying EH Grade steels in fillet welded joints were evaluated with both the hot spot stress method and the 1mm stress method. The thickness effect criterion for fatigue strength evaluation of welded of welded steel structures recommendations of the IIW was used to evaluate the fatigue strength of EH40 and EH36 and Both EH40 and EH36 have been compared with FAT 125 curve recommended in the IIW. Furthermore, fatigue strength of the welded tow and the ground conditions for Non-load-carrying EH36 based on the 1mm stress method has been discussed.

• Journal of Acupuncture Research
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• v.23 no.1
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• pp.1-14
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• 2006

Background : Recently, so many people are suffered from the allergic or auto-immune disease, and the representative disease is just Allergic Asthma. It is because human immune function has been decreased. Many treatments were done to treat this disease, and many methods were studied to increase immune function and to suppress the asthma. But, the effect of asthma-suppression and improvement of immune response of EH-HA(Ephedrae Herba Herbal Acupuncture) has not been studied in detail. To study the effects of EH-HA, we injected EH-HA at Joksamni(ST36) of C57BL/6 mice. Objectives : The purpose of this study is to investigate the effect of asthma-suppression and improvement of immune response of EH-HA(Ephedrae Herba Herbal Acupuncture). EH-HA was done at Joksamni(ST36) of the mice with ovalbumin-induced asthma. Methods : C57BL/6 mice were sensitized and challenged with OVA(ovalbumin) for 12 weeks. Two experimental groups were treated with different concentrations(1%, 0.1%) of EH-HA at Joksamni(ST36) for the later 8 weeks(3times/week). Results : 1. The lung weight of the group treated with EH-HA decreased significantly compared with that of control group. 2. The total cells in lung, total leukocytes and eosinophils in BALF of the group treated with EH-HA decreased significantly compared with those of control group. 3. Eosinophils in BALF of the group treated with EH-HA in photomicrographs decreased significantly compared with those of control group. 4. The concentrations of IL-13, IgE, IL-4 in serum and IL-4 in BALF of the group treated with EH-HA decreased significantly compared with those of control group. 5. The numbers of $Gr-1^+/CD11b^+\;cells,\;CD3e^-/CCR3^+\;cells,\;CD4^+\;cells,\;CD8^+\;cells,\;CD3e^+/CD69^+\;cells\;and\;IgE^+/B220^+\;cells$ in lung of the group treated with EH-HA decreased significantly compared with those of control group. 6. In RT-PCR, the mRNA expression of IL-4, IL-5 and IL-13 in the group treated with EH-HA decreased compared with those of control group. Conclusion : These results suggested that EH-HA at Joksamni(ST36) in C57BL/6mice may be effective to OVA-induced asthma of C57BL/6 mice.

• Journal of Korean Medicine Rehabilitation
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• v.24 no.4
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• pp.15-28
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• 2014

Objectives This study was carried out to find out the Antioxidant and Anti-inflammatory Effects of Components of Mahwangbujaseshin-tang in LPS-Stimulated RAW264.7 Macrophages. Methods There are 5 experimental groups. ; normal, control, EH (Ephedrae Herba), ALRP (Aconiti Lateralis Radix Preparata) and AR (Asiasari Radix). The extract of EH, ALRP and AR ($100{\mu}g/ml$) was added to each group. We examined cytotoxicity, total phenolic contents, DPPH and ABTS free radical scavenging activity, Intracellular ROS (reactive oxygen species) production, NO (Total Nitric oxide), iNOS (inducible nitric oxide synthase), PGE2 (prostaglandin E2), COX-2 (cyclooxygenase-2), $IL-1{\beta}$ ($interleukin-1{\beta}$), IL-6 (interleukin-6), $TNF-{\alpha}$ (tumor necrosis factor-${\alpha}$), MMP-9 (matrix metalloproteinase-9), TIMP-1 (tissue inhibitor of metalloproteinase-1) and HO-1 (heme oxygenase-1) expression level. Results 1. Total phenolic contents of EH were in the highest level. 2. DPPH and ABTS free radical scavenging activity of EH was in the highest level. 3. ROS production was significantly decreased in AR. 4. NO production was significantly decreased in EH, ALRP, AR and iNOS expression was decreased in EH, AR. 5. PGE2 and COX-2 expression was decreased in EH, AR. 6. $IL-1{\beta}$ production was significantly decreased in EH, AR and IL-6 production was significantly decreased in AR. $TNF-{\alpha}$ production was significantly decreased in ALRP, AR. 7. MMP-9 and TIMP-1 production were significantly decreased in EH. 8. HO-1 expression was significantly increased in EH. 9. With simultaneous usage of SnPP which is expression inhibitor of HO-1, NO, $IL-1{\beta}$, IL-6 and $TNF-{\alpha}$ production were partially increased in EH, ALRP, AR. Conclusions According to this study, Components of Mahwangbujaseshin-tang have anti-oxidants and anti-inflammation effects in LPS-Stimulated RAW264.7 Macrophages.