• BMB Reports
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• 제32권3호
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• pp.259-265
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• 1999

This study was designed to examine the anticarcinogenic effect of dietary supplementation with garlic powder on rat hepatocarcinogenesis. All rats were initiated by a single dose (200 mg/body weight) intraperitoneal injection of diethylnitrosamine (DEN), and three weeks later, subjected to two-thirds partial hepatectomy. Two weeks after initiation, four groups of rats were given experimental diets supplemented with 0 (control group), 0.5, 2.0, or 5.0% garlic powder for 6 weeks. Rats were sacrificed at eight weeks after initiation. The induction of placental glutathione S-transferase (GST-P) positive foci was significantly inhibited almost equally in all three groups fed garlic diets. Glucose 6-phosphatase (G6Pase) activity was increased in rats fed 0.5% and 2.0% garlic powder, and was negatively correlated with the number and area of GST-P positive foci. Thiobarbituric acid reactive substance (TBARS) contents were decreased in rats fed 2.0% and 5.0% garlic powder. Only 5.0% garlic powder supplementation significantly increased the glutathione content and the glutathione S-transferase activity, compared to the control group. Therefore, all levels of garlic powder, 0.5% to 5.0%, exerted an anti promotional effect during hepatocarcinogenesis. Dietary supplementation with garlic powder seemed to maintain microsomal membrane integrity by increasing G6Pase activities. Glutathione-dependent detoxifying enzymes did not seem to contribute to this protective effect directly. The present study suggests that garlic powder is effective in inhibiting the induction of GST-P positive foci, possibly by stabilizing the hepatic microsomal membrane.

• 한국식물병리학회지
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• 제13권4호
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• pp.248-254
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• 1997

순무우 모자이크 바이러스 Ca 계통(TuMV-Ca)의 외피 단백질을 대장균 NM522 strain에서 발현시켰다. 발현된 바이러스 단백질은 한천젤 이중확산법, ELISA와 Western blotting을 이용하여 확인하였다. 외피단백질 발현 벡터(pGEX-Tu)의 구축은 IPTG induction site를 지니는 pGEX-KG에 TuMV-Ca 외피단백질 유전자를 결합하였다. 최적 단백질 발현 조건은 pGEX-Tu를 지니는 대장균을 액체 배지 1 ml당 $A_{595}$=0.1/ml의 농도로 접종한 후 2시간 뒤에 IPTG를 최종 농도를 1 mM로 조절하여 induction 시키는 경우였다. 합성된 목적 단백질은 발현 벡터의 특성상 GST (Glutathion S-Transferase) 단백질과 결합된 형태로 약 59 kDa의 단백질이었다. (uMV CP 33 kDa + GST 26 kDa.)

• Journal of Ginseng Research
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• 제36권4호
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• pp.449-460
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• 2012

Plants have versatile detoxification systems to encounter the phytotoxicity of the wide range of natural and synthetic compounds present in the environment. Glutathione S-transferase (GST) is an enzyme that detoxifies natural and exogenous toxic compounds by conjugation with glutathione (GSH). Recently, several roles of GST giving stress tolerance in plants have demonstrated, but little is known about the role of ginseng GSTs. Therefore, this work aimed to provide further information on the GST gene present in Panax ginseng genome as well as its expression and function. A GST cDNA (PgGST) was isolated from P. ginseng cDNA library, and it showed the amino acid sequence similarity with theta type of GSTs. PgGST in ginseng plant was induced by exposure to metals, plant hormone, heavy metals, and high light irradiance. To improve the resistance against environmental stresses, full-length cDNA of PgGST was introduced into Nicotiana tabacum. Overexpression of PgGST led to twofold increase in GST-specific activity compared to the non-transgenic plants, and the GST overexpressed plant showed resistance against herbicide phosphinothricin. The results suggested that the PgGST isolated from ginseng might have a role in the protection mechanism against toxic materials such as heavy metals and herbicides.

• BMB Reports
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• 제40권4호
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• pp.511-516
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• 2007

A glutathione S-transferase (GST) related to the phi (F) class of enzymes only found in plants has been cloned from the Oryza sativa. The GST cDNA was cloned by PCR using oligonucleotide primers based on the OsGSTF5 (GenBank Accession No. $\underline{AF309382}$) sequences. The cDNA was composed of a 669-bp open reading frame encoding for 223 amino acids. The deduced peptide of this gene shared on overall identity of 75% with other known phi class GST sequences. On the other hands, the OsGSTF5 sequence showed only 34% identity with the sequence of the OsGSTF3 cloned by our previous study (Cho et al., 2005). This gene was expressed in Escherichia coli with the pET vector system and the gene product was purified to homogeneity by GSH-Sepharose affinity column chromatography. The expressed OsGSTF5 formed a homo-dimer composed of 28 kDa subunit and its pI value was approximately 7.8. The expressed OsGSTF5 displayed glutathione conjugation activity toward 1-chloro-2,4-dinitrobenzene and 1,2-epoxy-3-(p-nitrophenoxy)propane and glutathione peroxidase activity toward cumene hydroperoxide. The OsGSTF5 also had high activities towards the herbicides alachlor, atrazine and metolachlor. The OsGSTF5 was highly sensitive to inhibition by S-hexylGSH, benastatin A and hematin. We propose from these results that the expressed OsGSTF5 is a phi class GST and appears to play a role in the conjugation of herbicide and GPOX activity.

• 한국콘텐츠학회논문지
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• 제13권11호
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• pp.288-296
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• 2013

본 연구의 목적은 수근관증후군 뇌졸중 환자에서 경직정도에 따른 정중신경 단면적, 신경전도속도 및 상지기능 차이를 알아보고자 하였다. 연구대상은 성인 뇌졸중 환자 42명에서 CTS군 21명과 Non-CTS군 21명으로 선정하였다. 측정방법으로는 정중신경 단면적, 신경전도속도, GST, FMAS, CTS-FSS로 측정하였다. 연구결과, CTS군과 Non-CTS군 간 각 등급에서 정상측(p<.001)과 마비측(p<.001)의 정중신경 단면적, 정중 운동신경과 감각신경 기시잠시는 통계학적으로 유의한 차이가 있었다. CTS군과 Non-CTS군 간 각 등급에서 GST(p<.05), FMAS(p<.05), CTS-FSS(p<.001)는 통계학적으로 유의한 차이가 있었다. 본 연구는 수근관에 대한 병리역학적 내용을 제시함으로서 뇌졸중 환자의 상지기능훈련 시 고려해야할 내용 중 하나임을 제시하였다.

• Asian Pacific Journal of Cancer Prevention
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• 제13권12호
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• pp.6403-6407
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• 2012

Detoxifying enzymes are present in most epithelial cells of the human gastrointestinal tract where they protect against xenobiotics which may cause cancer. Induction of examples such as glutathione S-transferase (GST) and its thiol conjugate, glutathione (GSH) as well as NAD(P)H: quinoneoxidoreductase (NQO1) facilitate the excretion of carcinogens and thus preventing colon carcinogenesis. Pterostilbene, an analogue of resveratrol, has demonstrated numerous pharmacological activities linked with chemoprevention. This study was conducted to investigate the potential of pterostilbene as a chemopreventive agent using the HT-29 colon cancer cell line to study the modulation of GST and NQO1 activities as well as the GSH level. Initially, our group, established the optimum dose of 24 hours pterostilbene treatment using MTT assays. Then, effects of pterostilbene ($0-50{\mu}M$) on GST and NQO1 activity and GSH levels were determined using GST, NQO1 and Ellman assays, respectively. MTT assay of pterostilbene ($0-100{\mu}M$) showed no cytotoxicity toward the HT-29 cell line. Treatment increased GST activity in the cell line significantly (p<0.05) at 12.5 and $25.0{\mu}M$. In addition, treatment at $50{\mu}M$ increased the GSH level significantly (p<0.05). Pterostilbene also enhanced NQO1 activity significantly (p<0.05) at $12.5{\mu}M$ and $50{\mu}M$. Hence, pterostilbene is a potential chemopreventive agent capable of modulation of detoxifiying enzyme levels in HT-29 cells.

• Clinical and Experimental Pediatrics
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• 제51권3호
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• pp.262-266
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• 2008

목 적 : GSTs는 glutathione과 친전자성 화합물의 결합을 촉매하여 생체내에 독성 물질로부터 조직을 보호하는 효소로, 여러 다형성이 확인 되었으며 일부 GSTs의 null 유전자형을 가진 사람은 GSTs 단백을 생성하지 못하여 다양한 질병의 감수성에 영향을 미친다고 보고 되었다. 이것은 빌리루빈과 같은 non-substrate ligand와 결합하여 세포내로 운반하는 역할을 하는 대표적인 ligandin이며 빌리루빈을 간세포 내 소포체로 이동시켜 UGT를 통해 glucuronidation 시키는 역할을 한다. 이 연구에서는 빌리루빈 대사의 ligandin인 GSTs 중 GSTM1, GSTT1과 신생아 황달과 연관성이 있는 지 알아보고자 본 연구를 시행하였다. 방 법 : 혈청 빌리루빈 수치가 12 mg/dL 이상인 건강하고 위험인자가 없는 만삭아 중 신생아 고빌리루빈혈증 환아 88명, 대조군은 186명을 대상으로 혈액 0.5 cc를 채혈하여 DNA를 분류하였고 중합효소 연쇄 반응을 수행하여 DNA band를 확인하였다. 결 과 : 대조군의 GSTM1 null 유전형 58.1%, GSTT1의 null 유전형 53.2%였다. 환자군에서 GSTM1 null 유전형은 42% (P=0.0187), GSTT1 null 유전형은 31.8% (P=0.0014)로 통계학적 연관성이 있었다. GSTM1/GSTT1 null/null인 경우, 환자군에서 20명(22.7%)(P=0.0008), GSTM1/GSTT1 null/present인 경우 환자군에서 17명(19.3%) (P=0.0470), GSTM1/GSTT1 present/null인 경우 환자군에서 8명(9.1%) (P=0.0066)으로 나타났다 결 론 : GSTM1과 GSTT1 모두 환자군에서 null 유전형이 대조군에 비하여 더 적게 나타나 GSTs null 유전형이 신생아 고빌리루빈혈증의 위험인자는 아니었다.

• Preventive Nutrition and Food Science
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• 제4권1호
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• pp.52-56
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• 1999

This study has examined the effects of Aralia elata Seemann ethanol extract on antioxidant enzyme systems inrats along with benzo($\alpha$) pyrene(B(a)P) administration . The ethanol extract of Aralia elata Seemann (50mg/kg body wt.) was fed to rats for 4 weeks by stomach tubing. The extract administration increased antioxidant activities of glutathione sulfur transferase(GST) comparing to the control. also total superoxide dismutase(SOD) and Cu, Zn-SOD activities were stimulated. Catalase activities were increased by 50% with the extract feeding compared to the control . Combined administration of B($\alpha$)P and the extract increased GST activity in B($\alpha$) P group. Although total SOD acitivity was decreased , Cu, Zn-SOD was greately increased from 0.10unit to 0.18 unit and catalase activity also was increased compared to the group of B($\alpha$) P. GST activity in CLE group was 1.32 unit, increased by 33% comparing to the group CL of 0.99unit. Cu, Zn-SOD and catalase activities in thegroup fed high fat and ethanol extracts were increased by 25% and 39%, respectivley comparing to the group of high fat. In addition , total SOD was decreased but, Cu, Zn-SOD acitivity was increased from 0.09 unit to 0.18unit. Catalase activity was 76.05 unit in the group of B($\alpha$) P and extract comparing to 65.26 units in B($\alpha$)P group. Serum $\alpha$-tocopherol of rat was markedly increased by theextract. Administration of B9$\alpha$)P reduced $\alpha$-tocopherol levels in the serum, on the other hand, lard in the diet increased $\alpha$-tocopherol levels in the serum. The above results indicate that Aralia bud exerts antioxidant functions in vivo against B($\alpha$)P. Further research may be necessary for the identification fo the biologically active material.

• 약학회지
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• 제44권4호
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• pp.300-307
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• 2000

Expression of xenobiotic-metabolizing enzymes can be altered by xenobiotics, which represents changes in the production of reactive metabolic intermediates as well as toxicities in tissues. Metabolic intermediates derived from xenobiotics are considered to produce the reactive oxygen species including drug free radicals and hydroxyl free radicals, which would be ultimately responsible for drug-induced toxicities. The effects of 1,2-benzothiazine anti-inflammatory agents on the expression of xenobiotic-metabolizing enzymes including major cytochrome P450s, microsomal epoxide hydrolase (mEH) and glutathione S-transferase (GST) were studied in the liver with the aim of providing the part of information on potential production of reactive metabolites and hepatotoxicity by the agents. The synthetic compounds 24, 36 and 39 exhibited anti-inflammatory effects in rats as assessed by the Randall-Selitto method. The anti-inflammatory effect was detected as early as at 30 min after gavaging the agents with the ED5O being noted at 80 mg/kg, which was comparable to that of ibuprofen. Treatment of rats with each compound (100 mg/kg, 3d) resulted in no significant induction in the immunochemically-detectable cytochromes P45O 1A1/2, P450 2B1/2, P45O 2 Cl1 and P45O 2El. Changes in the mEN expression were also minimal, as evidenced by both Western blot and Northern blot analyses. Hepatic GST expression was slightly increased by the agents: GST Ya protein and mRNA expression was ～1.5-fold increased after treatment with compounds 24 and 39, whereas GST Yb1/2 and Yc1/2 mRNA levels were elevated 2- to 3-fold. In summary the effects of the synthetic 1,2-benzothiazines on the expression of major P45O, mEH and G57 were not significant, providing evidence that metabolic activation of the agents, potential drug interaction and hepatotoxicity would be minimal.

• International Journal of Industrial Entomology and Biomaterials
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• 제18권1호
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• pp.28-32
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• 2009

We describe here the cloning and characterization of a cDNA encoding the glutathione S-transferase (GST) from the bumblebee Bombus ignitus. The Delta-class B. ignitus GST (BiGSTD) gene spans 1668 bp and consists of four introns and five exons that encode 216 amino acid residues with a calculated molecular weight of approximately 24561 Da and a pI of 8.03. The N-terminal domain of BiGSTD has a conserved Ser residue, as well as conserved Lys, Pro, Glu, Ser and Tyr residues that are involved in the GSH-binding site of GST. The BiGSTD showed 60% protein sequence identity to the Bombyx mori GSTT1, 58% to Musca domestica GST, 57% to Drosophila melanogaster GST, and 55% to Anopheles gambiae GST1. BiGSTD was close to the insect-specific Delta class of GSTs in a phylogenetic tree. Northern blot analysis showed that BiGSTD is highly expressed in the fat body and midgut, and less so in the muscles of B. ignitus worker bees.