• Title/Summary/Keyword: cytochrome P-450 1A1

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Screening of Genetic Polymorphisms of CYP3A4 and CYP3A5 Genes

  • Lee, Jin Sol;Cheong, Hyun Sub;Kim, Lyoung Hyo;Kim, Ji On;Seo, Doo Won;Kim, Young Hoon;Chung, Myeon Woo;Han, Soon Young;Shin, Hyoung Doo
    • The Korean Journal of Physiology and Pharmacology
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    • v.17 no.6
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    • pp.479-484
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    • 2013
  • Given the CYP3A4 and CYP3A5's impact on the efficacy of drugs, the genetic backgrounds of individuals and populations are regarded as an important factor to be considered in the prescription of personalized medicine. However, genetic studies with Korean population are relatively scarce compared to those with other populations. In this study, we aimed to identify CYP3A4/5 polymorphisms and compare the genotype distributions among five ethnicities. To identify CYP3A4/5 SNPs, we first performed direct sequencing with 288 DNA samples which consisted of 96 Koreans, 48 European-Americans, 48 African-Americans, 48 Han Chinese, and 48 Japanese. The direct sequencing identified 15 novel SNPs, as well as 42 known polymorphisms. We defined the genotype distributions, and compared the allele frequencies among five ethnicities. The results showed that minor allele frequencies of Korean population were similar with those of the Japanese and Han Chinese populations, whereas there were distinct differences from European-Americans or African-Americans. Among the pharmacogenetic markers, frequencies of $CYP3A4^*1B$ (rs2740574) and $CYP3A5^*3C$ (rs776742) in Asian groups were different from those in other populations. In addition, minor allele frequency of $CYP3A4^*18$ (rs28371759) was the highest in Korean population. Additional in silico analysis predicted that two novel non-synonymous SNPs in CYP3A5 (+27256C>T, P389S and +31546T>G, I488S) could alter protein structure. The frequency distributions of the identified polymorphisms in the present study may contribute to the expansion of pharmacogenetic knowledge.

Effect of Benzoyl Peroxide on the Activity of Drug-metabolizing Enzyme System and Lipid Peroxidation in Rats (Benzoyl peroxide가 흰쥐의 지질과산화현상에 미치는 영향)

  • Lee, H.W.;Rhee, K.S.;Hong, S.U.
    • The Korean Journal of Pharmacology
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    • v.18 no.1
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    • pp.55-63
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    • 1982
  • Lipid peroxidation is the reaction of oxidative deterioration of polyunsaturated lipids and this peroxidation involves the direct reaction of oxygen and lipid to form free radical intermediates, which can lead to autocatalysis. As results of the extensive studies on the lipid peroxidation by many authors, the relationship between lipid peroxidation and the drug metabolizing system as well as the actions of free radicals on the peroxidation was reasonably well known. For a long time, the mechanism of hepatotoxicity of $CCl_4$ was not clearly understood. However, it is now quite well established that $CCl_4$ is activated in vivo to a free radical which is a highly reactive molecule. Therefore, lipid peroxidation which induces the reduction of cytochrome P-450 and aminopyrine demethylase activity is known as decisive event of $CCl_4$ hepatotoxicity. On the other hand, it was also reported that singlet molecular oxygen produces lipid peroxidation in liver microsomes. In this study the effects of benzoyl peroxide on the lipid peroxidation and drug-metabolizing enzyme were examined. Benzoyl peroxide mixed with starch and phosphates etc. is usually used as a food additive for flour bleaching and maturing purpose because of its oxidative property. Albino rats were used for the experimental animals. Benzoyl peroxide was suspended in soybean oil and sesame oil and administered intraperitoneally or orally. TBA value and aminopyrine demethylase activity were determined in liver microsomal fraction and serum. The results were summerized as following. 1) Body weights of animals administered benzoyl peroxide suspension were decreased while that of oil administered group were increased. 2) The activity of aminopyrine demethylase was generally decreased in animals administered oil suspension of benzoyl peroxide. Furthermore, the marked reduction of the enzyme activity was observed in animals administered benzoyl peroxide intraperitoneally. 3) Generally, microsomal TBA values as well as serum TBA were significantly elevated in benzoyl peroxide group in comparison with the control group. However, the more remarkable increase of serum TBA than microsomal TBA was observed in animals administered orally for 6 days. 4) Specifically, the changing pattern of TBA value was notable in serum rather than in liver microsome by intraperitoneal administration of benzoyl peroxide.

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Quality and Availability Evaluation of Human Hepatocytes Isolated from Resected Partial Livers for Toxicology and Drug Metabolism Studies in Korea (독성 및 약물대사 연구를 위한 한국인 부분 간 유래 간세포의 품질 및 활용성 평가)

  • Noh, Jeong-Kwon;Jang, In Keun;Kim, Hyo Eun;Lee, Jong Eun;Yang, Mal Sook;Jang, Eun Mi;Lee, Ji-Hyun;Park, Hey-Jung;Kim, Young-A;Lee, Suk-Koo;Jeong, Ho-Sang;Ahn, Joon-Ik;Lee, Doo-Hoon
    • KSBB Journal
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    • v.29 no.1
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    • pp.58-66
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    • 2014
  • Demand for in vitro pharmacological evaluation and toxicity test using human hepatocytes has been increasing. In USA and Europe, human hepatocytes obtained from donated whole liver unsuitable for transplantation were distributed to researchers and deposited in cell bank facility as cryopreserved vial. In Korea, however, incidence of transplantation- inappropriate whole liver has been quite low and the whole livers almost have so severe liver disease such as fatty or fibrotic liver that cannot meet the demand. In this study we aimed to isolate human hepatocytes from liver resection surgery-originated partial liver, and assure the isolated human hepatocytes and its cryopreserved hepatocytes to be qualified for the in vitro pharmacological evaluation and drug toxicity tests. We compared those with commercially available human hepatocyte, BD $GenTest^{TM}$ by cell morphology, hepatic gene expression, urea synthesis, albumin secretion, ammonia removal, and cytochrome P450 induction activities. Changes in hepatotoxic gene expression after cryopreservation are evaluated with a typical hepatotoxic drug, acetaminophen. Consequently, the fresh hepatocytes from the partial liver and its cryopreserved hepatocytes expressed their intrinsic hepatic functions well and showed equal hepatotoxicity gene expression trend regardless to cryopreservation. Therefore, liver resection surgery-originated partial liver can be used as a useful source of human hepatocytes for various pharmacological and hepatotoxicity test.

Differences in Gene Expression Profiles Reflecting Differences in Drug Sensitivity to Acetaminophen in Normal and Transformed Hepatic Cell Lines In vitro

  • Jeong, Youn-Kyoung;Kang, Jin-Seok;Kim, Joo-Whan;Suh, Soo-Kyung;Lee, Michael;Kim, Seung-Hee;Lee, Sang-Kook;Park, Sue-Nie
    • Molecular & Cellular Toxicology
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    • v.5 no.1
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    • pp.32-43
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    • 2009
  • Acetaminophen (APAP) overdose is known to cause severe hepatotoxicity mainly through the depletion of glutathione. In this study, we compared the cytotoxic effects of APAP on both a normal murine hepatic cell line, BNL CL.2, and its SV40-transformed cell line, BNL SV A.8. Gene expression profiles for APAP-treated cells were also obtained using microarray and analyzed to identify differences in genes or profiles that may explain the differences of susceptibility to APAP in these cell lines. These two cell lines exhibited different susceptibilities to APAP (0-$5,000{\mu}M$); BNL SV A.8 cells were more susceptible to APAP treatment compared to BNL CL.2 cells. A dose of $625{\mu}M$ APAP, which produced significant differences in cytotoxicity in these cell lines, was tested. Microarray analysis was performed to identify significant differentially expressed genes (DEGs) irrespective of APAP treatment. Genes up-regulated in BNL SV A.8 cells were associated with immune response, defense response, and apoptosis, while down-regulated genes were associated with catalytic activity, cell adhesion and the cytochrome P450 family. Consistent with the cytotoxicity data, no significant DEGs were found in BNL CL.2 cells after treatment with $625{\mu}M$ APAP, while cell cycle arrest and apoptosis-related genes were up-regulated in BNL SV A.8 cells. Based on the significant fold-changes in their expression, a genes were selected and their expressions were confirmed by quantitative real-time RT-PCR; there was a high correlation between them. These results suggest that gene expression profiles may provide a useful method for evaluating drug sensitivity of cell lines and eliciting the underlying molecular mechanism. We further compared the genes identified from our current in vitro studies to the genes previously identified in our lab as regulated by APAP in both C57BL/6 and ICR mice in vivo. We found that a few genes are regulated in a similar pattern both in vivo and in vitro. These genes might be useful to develop as in vitro biomarkers for predicting in vivo hepatotoxicity. Based on our results, we suggest that gene expression profiles may provide useful information for elucidating the underlying molecular mechanisms of drug susceptibility and for evaluating drug sensitivity in vitro for extrapolation to in vivo.

Protective Effects of 2-(Allylthio)pyrazine on Retinoyl Palmitate- and Pyridine-Potentiated Carbon tetrachloride- induced Hepatotoxicity: Effect on ${\Phi}x$-174 DNA Strand Breakage (비타민 A 및 피리딘으로 유발된 사염화탄소 유발성 간독성에 대한 2-(알릴티오)피라진의 보호효과: ${\Phi}$x-174 DNA 손상에 미치는 효과)

  • Kim, Sang-Geon;Cho, Joo-Youn;Choi, Sung-Hee;Kim, Nak-Doo
    • YAKHAK HOEJI
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    • v.40 no.6
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    • pp.727-733
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    • 1996
  • 2-(Allylthio)pyrazine is effective in selectively suppressing constitutive and inducible expression of cytochrome P450 2E1. The effect of 2-(allylthio)pyrazine against potentiat ed chemical injury was studied in rats. Vitamin-A pretreatment of rats substantially increased carbon tetrachloride hepatotoxicity, as supported by an ~4-fold increase in serum alanine aminotransferase (ALT) activity. Concomitant pretreatment of rats with 2-(allylthio)pyrazine at the daily dose of 200mg/kg resulted in a 76% decrease in vitamin-A-potentiated hepatotoxicity, which supported the possibility that 2-(allylthio)pyrazine protects the liver against chemical-induced hepatic injury by the mechanism associated with Kupffer cell inactivation. Pyridine pretreatment caused substantial enhancement in carbon tetrachloride hepatotoxicity. 2-(Allylthio)pyrazine treatment of rats reduced the pyridine-potentiated toxicity in a dose-dependent manner. Animals treated with both pyridine and 2-(allylthio)pyrazine prior to intoxicating dose of CCl$_4$ resulted in 85% and 47% decreases in pyridine-increased triglycerides and cholesterol levels in the liver. The protective effect of 2-(allylthio)pyrazine on the DNA strand breakage induced by benzenetriol was assessed by measuring the conversion of supercoiled ${\Phi}x$-174 DNA to the open relaxed form. 2-(Allylthio)pyrazine blocked the benzenetriol-induced conversion of supercoiled DNA to open circular form in a dose-dependent manner. The presence of 2-(allylthio)pyrazine at the doses from I to 10mM in the incubation mixture containing 5 ${\mu}$M benzenetriol completely protected benzenetriol-induced DNA strand breakage with the EC50 for the 2-(allylthio)pyrazine blocking being noted as ~220 ${\mu}$M, whereas allyl disulfide exerted protecting effect at relatively high concentrations (i.e. ~850 ${\mu}$M), suggesting that 2-(allylthio)pyrazine effectively scavenges the reactive oxygen species. These results provide evidence that 2-(allylthio)pyrazine blocks vitamin A- or pyridine-potentiated CCl$_4$ hepatotoxicity and that the agent is active in protecting DNA by scavenging the reactive oxygen species.

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Mycelial Culture of Lentinus edodes Alleviates Rat Liver Toxicity Induced by Carbon Tetrachloride and Ethanol (표고버섯균사체의 사염화탄소 및 알콜로 처리된 흰쥐 간기능 보호 효과)

  • Ha, Yeong-L.;Kim, Young-S.;Ahn, Chae-R.;Kweon, Jung-M.;Park, Cherl-W.;Ha, Young-K.;Kim, Jeong-O.
    • Journal of Life Science
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    • v.20 no.1
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    • pp.133-141
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    • 2010
  • The protective effect of a mixed powder from solid-cultured and liquid-cultured Lentinus edodes mycelia (2:1, w/w) (designate LED) on the carbon tetrachloride ($CCl_4$)- and ethanol-induced hepatotoxicity of male Sprague-Dawley (SD) rat was investigated. In the $CCl_4$-induced rat hepatotoxicity experiment, rats of 4 groups (6 rats/group) were administere with Normal (0.2 ml distilled water), Control (0.2 ml distilled water), LED (LED 200 mg/kg BW + 0.2 ml distilled water), and Silymarin (200 mg/kg BW + 0.2 ml distilled water), p.o., daily for 2 weeks. Afterwards, all groups except for the Normal group were subjected to abdominal injection with $CCl_4$ ($CCl_4$ : corn oil, 1:1 v/v; 0.5 ml/kg BW). For the ethanol- induced rat hepatotoxicity experiment, rats were divided into 5 groups (5 rats/group): Normal; Pair-fed control (PFC); Control (ethanol); LED (ethanol + LED 200 mg/kg BW); and Silymarin (ethanol + silymarin 200 mg/kg BW). Rats of the Normal and PFC groups were fed a basal liquid diet, and rats of the Control, LED, and Silymarin groups were fed a liquid ethanol diet containing LED or Silymarin. Eight weeks later, blood and liver samples were collected to analyze biomarkers. In $CCl_4$-induced SD rats, LED elevated hepatic superoxide dismutase (SOD), catalase, and glutathione peroxidase (GSH peroxidase) activities and thiobarbituric reactive substances (TBARS) were reduced, resulting in the reduction of glutamate-oxalate transaminase (GOT), glutamate-pyruvate transaminase (GPT) and lactic dehydrogenase (LDH) activities in plasma. Similar results of these enzymes and biochemical markers in both liver tissues and plasma were seen in ethanol-induced hepatotoxicity of SD rats. In addition, elevated alcohol dehydrogenase (ADH) activity and reduced expression of cytochrome p450 mixed monooxygenase enzyme (CYP2E1) were seen in liver tissues from ethanol-treated rats by LED treatment. These effects of LED were similar to those of Silymarin. In in vitro experiments, LED showed antioxidant activity in a 2,2-diphenyl-1-picrylhydrazyl (DPPH) system and mouse liver mitochondria system induced by NADPH/$Fe^{2+}$ and cumine hydroperoxide (CuOOH). These results indicate that LED protected SD rat hepatotoxicity, induced by $CCl_4$ and ethanol, through its antioxidative activity and might be useful as a material for protection from hepatoxicity in humans.

Integrated transcriptomic analysis on small yellow follicles reveals that sosondowah ankyrin repeat domain family member A inhibits chicken follicle selection

  • Zhong, Conghao;Liu, Zemin;Qiao, Xibo;Kang, Li;Sun, Yi;Jiang, Yunliang
    • Animal Bioscience
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    • v.34 no.8
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    • pp.1290-1302
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    • 2021
  • Objective: Follicle selection is an important process in chicken egg laying. Among several small yellow (SY) follicles, the one exhibiting the highest expression of follicle stimulation hormone receptor (FSHR) will be selected to become a hierarchal follicle. The role of lncRNA, miRNA and other non-coding RNA in chicken follicle selection is unclear. Methods: In this study, the whole transcriptome sequencing of SY follicles with different expression levels of FSHR in Jining Bairi hens was performed, and the expression of 30 randomly selected mRNAs, lncRNAs and miRNAs was validated by quantitative real-time polymerase chain reaction. Preliminary studies and bioinformatics analysis were performed on the selected mRNA, lncRNA, miRNA and their target genes. The effect of identified gene was examined in the granulosa cells of chicken follicles. Results: Integrated transcriptomic analysis on chicken SY follicles differing in FSHR expression revealed 467 differentially expressed mRNA genes, 134 differentially expressed lncRNA genes and 34 differentially expressed miRNA genes, and sosondowah ankyrin repeat domain family member A (SOWAHA) was the common target gene of three miRNAs and one lncRNA. SOWAHA was mainly expressed in small white (SW) and SY follicles and was affected by follicle stimulation hormone (FSH) treatment in the granulosa cells. Knockdown of SOWAHA inhibited the expression of Wnt family member 4 (Wnt4) and steroidogenic acute regulatory protein (StAR) in the granulosa cells of prehierarchal follicles, while stimulated Wnt4 in hierarchal follicles. Overexpression of SOWAHA increased the expression of Wnt4 in the granulosa cells of prehierarchal follicles, decreased that of StAR and cytochrome P450 family 11 subfamily A member 1 in the granulosa cells of hierarchal follicles and inhibited the proliferation of granulosa cells. Conclusion: Integrated analysis of chicken SY follicle transcriptomes identified SOWAHA as a network gene that is affected by FSH in granulosa cells of ovarian follicles. SOWAHA affected the expression of genes involved in chicken follicle selection and inhibited the proliferation of granulosa cells, suggesting an inhibitory role in chicken follicle selection.

Protective Effects of Angelica keiskei Extracts Against D-Galactosamine (GalN)-induced Hepatotoxicity in Rats

  • Choi, Sang-Hoon;Park, Kwan-Ha
    • Journal of Food Hygiene and Safety
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    • v.26 no.3
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    • pp.235-241
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    • 2011
  • Although the vegetable Angelica keiskei (AK) has widely been utilized for the purpose of general health improvement among Korean population, its functionalities are not very well defined. In this study, we examined the effects of methanol extract of AK in rats on the biochemical changes induced by two hepatotoxins, D-galactosamine (GalN) and carbon tetrachloride ($CCl_4$). AK was orally administered once daily for 7 days to male rats at 200 and 500 mg/kg, before hepatotoxins. Effects of AK were assessed 24 hr later. AK pretreatments at 200 and 500 mg/kg significantly blunted GalN-induced elevation in liver lipid peroxidation, plasma aspartate-transaminase (AST) and alanine-transaminase (ALT) activities. AK also prevented, after 500 mg/kg but not after 200 mg/kg, the GalN-induced elevation in triglyceride, total cholesterol and LDL-cholesterol levels. Differently from against GalN-induced toxicity, AK did further elevate the $CCl_4$-induced rise in AST, ALT and lipid peroxidation. These results suggest that AK, when pre-administered prior to GalN, exerted protective effects against GalN-induced hepatotoxicity, in contrast however, AK exacerbated that induced by $CCl_4$. To explore possible mechanism for the toxicity-potentiating effects of AK on $CCl_4$, the activity of hepatic drug metabolism after AK treatment was assessed. It was observed that AK increased the activity of aniline hydroxaylase, a cytochrome P450 isoenzyme responsible for metabolic activation of $CCl_4$. This finding suggests that hepatoprotective effects of AK are not equally expected depending on hepatotoxins employed.

A study on the Effects of Rehmannia Radix and Eukmigihwangtang (EMGHT) on Antioxidation Activity in Aging Rats (숙지황(熟地黃)과 육미지황탕(六味地黃湯)이 노화과정(老化過程) 흰쥐에서의 항산화(抗酸化) 기전(機轉)에 미치는 영향(影響))

  • Ahn, Sang-Won;Lee, Cheol-wan
    • Journal of Haehwa Medicine
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    • v.8 no.1
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    • pp.593-623
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    • 1999
  • This experimental study was designed to verify the anti-aging efficacy of Eukmigihwangtang (EMGHT) and Rehmannia Radix, and determine the specific role and actions of Rehmannia Radix. Normal rat (2 months old), aging rat (8 months old), and pathologically induced rat (2 months old, injected 30mg/kg of streptozotocin) are observed to study the aging eliciting factors such as peroxide contents and enzyme activities. The following results were obtained in this study: 1. For the body weight changes, normal group given Rehmannia Radix showed decrease in the body weight compared to the control group, aging group given EMGHT and Rehmannia Radix showed significant decrease in the body weight, and STZ injected group showed suppression to the body weight loss when given EMGHT and Rehmannia Radix. 2. For the content changes in serum lipid peroxide, normal group showed increasing level as the rat gets older. Aging group and STZ injected group given EMGHT and Rehmannia Radix showed significant decrease in the lipid peroxide level compared to the control group. Decrease was more prominant in the group given EMGHT. 3. For the changes in serum hydroxyl radical, normal group did not show significant changes, but aging group and STZ injected group given EMGHT and Rehmannia Radix showed significant decrease in the hydroxyl radical level compared to the control group. Decrease was more prominant in the group given EMGHT. 4. For the changes in serum superoxide dismutase (SOD) activity, normal group did not show significant changes, but aging group given EMGHT and Rehmannia Radix showed significant increase in the SOD activity compared to the control group. STZ injected group given EMGHT and Rehmannia Radix showed significant decrease in the SOD activity compared to the control group. 5. For the content changes in hepatic lipid peroxide, aging group and STZ injected group given EMGHT and Rehmannia Radix showed significant decrease in the lipid peroxide level compared to the control group. 6. For the changes in hepatic cytochrome P-450 activity, aging group and STZ injected group given EMGHT and Rehmannia Radix showed significant decrease compared to the control group. Cytochrome b5 activity was significantly decreased only in the STZ injected group given EMGHT and Rehmannia Radix. 7. For the changes in hepatic aminopyrine demethylase and aniline hydroxylase activity, aging group given EMGHT and Rehmannia Radix showed significant decrease compared to the control group. STZ injected group given EMGHT and Rehmannia Radix showed significant increase in the aminopyrine demethylase activity, and showed significant decrease in the aniline hydroxylase activity compared to the control group. 8. For the content changes in hepatic protein bound-SH and nonprotein bound-SH, againg group and STZ injected group given EMGHT and Rehmannia Radix showed significant increase compared to the control group. 9. For the content changes in hepatic glutathione level, aging group and STZ injected group given EMGHT and Rehmannia Radix showed significant increase compared to the control group. 10. For the changes in hepatic glutathione S-transferase activity, aging group and STZ injected group given EMGHT and Rehmannia Radix showed significant increase and decrease, respectively, compared to the control group. 11. For the changes in hepatic glutathione reductase activity, aging group and STZ injected group given EMGHT and Rehmannia Radix showed significant increase compared to the control group, while $\gamma$-Glutamylcystein synthetase activity did not show significant changes. 12. For the changes in hepatic superoxide dismutase activity, aging group and STZ injected group given EMGHT and Rehmannia Radix showed significant decrease compared to the control group. From the above results, the antioxidant effects of EMGHT and Rehmannia Radix were proved, as well as the role of Rehmannia Radix, a chief of EMGHT, was examined. In addition, since no change was reconized as the quantity of Rehmannia Radix and the order herbs increased, the reasonableness on EMGHT was proven with respect to its composition and quantity. Thus, the significance of EMGHT could be objectively exmined in terms of its composition and quantity. Considering animals used in the experiment, there were obvious changes in aging rats and pathologically induced rats than in normal rats. Consequently, it was noticeable that EMGHT and Rehmannia Radix were working selectively on the subjects.

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Evolutionary Explanation for Beauveria bassiana Being a Potent Biological Control Agent Against Agricultural Pests

  • Han, Jae-Gu
    • 한국균학회소식:학술대회논문집
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    • 2014.05a
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    • pp.27-28
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    • 2014
  • Beauveria bassiana (Cordycipitaceae, Hypocreales, Ascomycota) is an anamorphic fungus having a potential to be used as a biological control agent because it parasitizes a wide range of arthropod hosts including termites, aphids, beetles and many other insects. A number of bioactive secondary metabolites (SMs) have been isolated from B. bassiana and functionally verified. Among them, beauvericin and bassianolide are cyclic depsipeptides with antibiotic and insecticidal effects belonging to the enniatin family. Non-ribosomal peptide synthetases (NRPSs) play a crucial role in the synthesis of these secondary metabolites. NRPSs are modularly organized multienzyme complexes in which each module is responsible for the elongation of proteinogenic and non-protein amino acids, as well as carboxyl and hydroxyacids. A minimum of three domains are necessary for one NRPS elongation module: an adenylation (A) domain for substrate recognition and activation; a tholation (T) domain that tethers the growing peptide chain and the incoming aminoacyl unit; and a condensation (C) domain to catalyze peptide bond formation. Some of the optional domains include epimerization (E), heterocyclization (Cy) and oxidation (Ox) domains, which may modify the enzyme-bound precursors or intermediates. In the present study, we analyzed genomes of B. bassiana and its allied species in Hypocreales to verify the distribution of NRPS-encoding genes involving biosynthesis of beauvericin and bassianolide, and to unveil the evolutionary processes of the gene clusters. Initially, we retrieved completely or partially assembled genomic sequences of fungal species belonging to Hypocreales from public databases. SM biosynthesizing genes were predicted from the selected genomes using antiSMASH program. Adenylation (A) domains were extracted from the predicted NRPS, NRPS-like and NRPS-PKS hybrid genes, and used them to construct a phylogenetic tree. Based on the preliminary results of SM biosynthetic gene prediction in B. bassiana, we analyzed the conserved gene orders of beauvericin and bassianolide biosynthetic gene clusters among the hypocrealean fungi. Reciprocal best blast hit (RBH) approach was performed to identify the regions orthologous to the biosynthetic gene cluster in the selected fungal genomes. A clear recombination pattern was recognized in the inferred A-domain tree in which A-domains in the 1st and 2nd modules of beauvericin and bassianolide synthetases were grouped in CYCLO and EAS clades, respectively, suggesting that two modules of each synthetase have evolved independently. In addition, inferred topologies were congruent with the species phylogeny of Cordycipitaceae, indicating that the gene fusion event have occurred before the species divergence. Beauvericin and bassianolide synthetases turned out to possess identical domain organization as C-A-T-C-A-NM-T-T-C. We also predicted precursors of beauvericin and bassianolide synthetases based on the extracted signature residues in A-domain core motifs. The result showed that the A-domains in the 1st module of both synthetases select D-2-hydroxyisovalerate (D-Hiv), while A-domains in the 2nd modules specifically activate L-phenylalanine (Phe) in beauvericin synthetase and leucine (Leu) in bassianolide synthetase. antiSMASH ver. 2.0 predicted 15 genes in the beauvericin biosynthetic gene cluster of the B. bassiana genome dispersed across a total length of approximately 50kb. The beauvericin biosynthetic gene cluster contains beauvericin synthetase as well as kivr gene encoding NADPH-dependent ketoisovalerate reductase which is necessary to convert 2-ketoisovalarate to D-Hiv and a gene encoding a putative Gal4-like transcriptional regulator. Our syntenic comparison showed that species in Cordycipitaceae have almost conserved beauvericin biosynthetic gene cluster although the gene order and direction were sometimes variable. It is intriguing that there is no region orthologous to beauvericin synthetase gene in Cordyceps militaris genome. It is likely that beauvericin synthetase was present in common ancestor of Cordycipitaceae but selective gene loss has occurred in several species including C. militaris. Putative bassianolide biosynthetic gene cluster consisted of 16 genes including bassianolide synthetase, cytochrome P450 monooxygenase, and putative Gal4-like transcriptional regulator genes. Our synteny analysis found that only B. bassiana possessed a bassianolide synthetase gene among the studied fungi. This result is consistent with the groupings in A-domain tree in which bassianolide synthetase gene found in B. bassiana was not grouped with NRPS genes predicted in other species. We hypothesized that bassianolide biosynthesizing cluster genes in B. bassiana are possibly acquired by horizontal gene transfer (HGT) from distantly related fungi. The present study showed that B. bassiana is the only species capable of producing both beauvericin and bassianolide. This property led to B. bassiana infect multiple hosts and to be a potential biological control agent against agricultural pests.

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