Fluoxetine-induced toxicity results in human placental glutathione S-transferase-π (GST-π) dysfunction.

PubMed

Dalmizrak, Ozlem; Kulaksiz-Erkmen, Gulnihal; Ozer, Nazmi

2016-10-01

The antidepressant drug fluoxetine (FLU) is considered in the group of selective serotonine re-uptake inhibitors. Its distribution in brain and binding to human brain glutathione S-transferase-π (GST-π) have been shown. FLU can cross blood brain barrier and placenta, accumulate in fetus and may cause congenital malformations. To elucidate the interaction of placental GST-π with FLU. First, concentration-dependent inhibition of human placental GST-π was evaluated by using different FLU concentrations and then 0.3125, 0.625, 1.25, 2.5 and 5 mM FLU concentrations were chosen and tested while keeping GSH concentration constant and 1-chloro-2,4-dinitrobenzene (CDNB) concentration varied and vice versa. The data were evaluated with different kinetic models and Statistica 9.00 for Windows. The Vm, at variable [CDNB] (142 ± 16 U/mg protein) was 3 times higher than the Vm obtained at variable [GSH] (49 ± 4 U/mg protein). On the other hand, the Km for CDNB was ∼10 times higher than the Km for GSH (1.99 ± 0.36 mM versus 0.21 ± 0.06 mM). The IC50 value for FLU was 8.6 mM. Both at constant [CDNB] and variable [GSH] and at constant [GSH] and variable [CDNB] the inhibition types were competitive with the Ki values of 5.62 ± 4.37 and 8.09 ± 1.27 mM, respectively. Although the Ki values obtained for FLU in vitro are high, due to their uneven distribution, long elimination time and inhibitory behavior on detoxification systems, it may cause defects in adults but these effects may be much more severe in fetus and result in congenital malformations.

Genome-Wide Identification, Characterization, and Expression Profiling of Glutathione S-Transferase (GST) Family in Pumpkin Reveals Likely Role in Cold-Stress Tolerance

PubMed Central

Abdul Kayum, Md.; Nath, Ujjal Kumar; Park, Jong-In; Choi, Eung Kyoo; Song, Jae-Young; Kim, Hoy-Taek; Nou, Ill-Sup

2018-01-01

Plant growth and development can be adversely affected by cold stress, limiting productivity. The glutathione S-transferase (GST) family comprises important detoxifying enzymes, which play major roles in biotic and abiotic stress responses by reducing the oxidative damage caused by reactive oxygen species. Pumpkins (Cucurbita maxima) are widely grown, economically important, and nutritious; however, their yield can be severely affected by cold stress. The identification of putative candidate genes responsible for cold-stress tolerance, including the GST family genes, is therefore vital. For the first time, we identified 32 C. maxima GST (CmaGST) genes using a combination of bioinformatics approaches and characterized them by expression profiling. These CmaGST genes represent seven of the 14 known classes of plant GSTs, with 18 CmaGSTs categorized into the tau class. The CmaGSTs were distributed across 13 of pumpkin’s 20 chromosomes, with the highest numbers found on chromosomes 4 and 6. The large number of CmaGST genes resulted from gene duplication; 11 and 5 pairs of CmaGST genes were segmental- and tandem-duplicated, respectively. In addition, all CmaGST genes showed organ-specific expression. The expression of the putative GST genes in pumpkin was examined under cold stress in two lines with contrasting cold tolerance: cold-tolerant CP-1 (C. maxima) and cold-susceptible EP-1 (Cucurbita moschata). Seven genes (CmaGSTU3, CmaGSTU7, CmaGSTU8, CmaGSTU9, CmaGSTU11, CmaGSTU12, and CmaGSTU14) were highly expressed in the cold-tolerant line and are putative candidates for use in breeding cold-tolerant crop varieties. These results increase our understanding of the cold-stress-related functions of the GST family, as well as potentially enhancing pumpkin breeding programs. PMID:29439434

Glutathione-S-transferase polymorphisms (GSTM1, GSTT1 and GSTP1) and acute leukemia risk in Asians: a meta-analysis.

PubMed

Tang, Zhen-Hai; Zhang, Chi; Cheng, Pan; Sun, Hong-Min; Jin, Yu; Chen, Yuan-Jing; Huang, Fen

2014-01-01

The association between glutathione-S-transferase polymorphisms (GSTM1, GSTT1 and GSTP1) and risk of acute leukemia in Asians remains controversial. This study was therefore designed to evaluate the precise association in 23 studies identified by a search of PubMed and several other databases, up to December 2013. Using random or fixed effects models odds ratios (ORs) with corresponding 95% confidence intervals (CIs) were calculated. Heterogeneity across studies was assessed, and funnel plots were constructed to test for publication bias. The meta-analysis showed positive associations between GST polymorphisms (GSTM1 and GSTT1 but not GSTP1) and acute leukemia risk [(OR=1.47, 95% CI 1.18-1.83); (OR=1.32, 95% CI 1.07-1.62); (OR=1.01, 95% CI 0.84-1.23), respectively] and heterogeneity between the studies. The results suggested that the GSTM1 null genotype and GSTT1null genotype, but not the GSTP1 polymorphism, might be a potential risk factors for acute leukemia. Further well-designed studies are needed to confirm our findings.

Functional variability of glutathione S-transferases in Basque populations.

PubMed

Iorio, Andrea; Piacentini, Sara; Polimanti, Renato; De Angelis, Flavio; Calderon, Rosario; Fuciarelli, Maria

2014-01-01

Glutathione S-transferases (GSTs) are enzymes involved in Phase II reactions. They play a key role in cellular detoxification. Various studies have shown that genes coding for the GST are highly polymorphic and some of these variants are directly associated with a decrease of enzyme activity making individuals more susceptible to different clinical phenotypes. The aim of this study is to investigate the genetic variability of GST genes among human populations. We have focused our attention on the polymorphic variants of the GSTA1, GSTM1, GSTO1, GSTO2, GSTP1, GSTT1, and GSTT2B genes. These polymorphisms were analyzed in a whole sample of 151 individuals: 112 autochthonous Navarrese Basques, and 39 non-autochthonous Navarrese Basques. DNA extraction from plasma was performed by using the phenol:chloroform:isoamylic alcohol method. Genotyping of the gene polymorphisms was performed by PCR Multiplex and the PCR-RFLP method. We applied correspondence analysis and built frequency-maps to compare the genetic structure in worldwide populations. Our results were compared with data available on the Human Genome Diversity Project (HGDP) and on the 1,000 Genomes Project to obtain information on the functional variability of GSTs in Basques. Our data indicated that Basque communities showed a higher differentiation of certain functional GST variants (i.e., GSTM1-positive/null genotype, GSTP1*I105V, and GSTT2B*1/0) than other European and Mediterranean populations. This might account for epidemiological differences in the predisposition to diseases and drug response among Basques and could be used to design and interpret genetic association studies for this particular population. Copyright © 2014 Wiley Periodicals, Inc.

Differential Roles for VviGST1, VviGST3, and VviGST4 in Proanthocyanidin and Anthocyanin Transport in Vitis vinífera

PubMed Central

Pérez-Díaz, Ricardo; Madrid-Espinoza, José; Salinas-Cornejo, Josselyn; González-Villanueva, Enrique; Ruiz-Lara, Simón

2016-01-01

In plant cells, flavonoids are synthesized in the cytosol and then are transported and accumulated in the vacuole. Glutathione S-transferase-mediated transport has been proposed as a mechanism involved in flavonoid transport, however, whether binding of flavonoids to glutathione S-transferase (GST) or their transport is glutathione-dependent is not well understood. Glutathione S-transferases from Vitis vinífera (VviGSTs) have been associated with the transport of anthocyanins, however, their ability to transport other flavonoids such as proanthocyanidins (PAs) has not been established. Following bioinformatics approaches, we analyzed the capability of VviGST1, VviGST3, VviGST4, and Arabidopsis TT19 to bind different flavonoids. Analyses of protein-ligand interactions indicate that these GSTs can bind glutathione and monomers of anthocyanin, PAs and flavonols. A total or partial overlap of the binding sites for glutathione and flavonoids was found in VviGST1, and a similar condition was observed in VviGST3 using anthocyanin and flavonols as ligands, whereas VviGST4 and TT19 have both sites for GSH and flavonoids separated. To validate the bioinformatics predictions, functional complementation assays using the Arabidopsis tt19 mutant were performed. Overexpression of VviGST3 in tt19-1 specifically rescued the dark seed coat phenotype associated to correct PA transport, which correlated with higher binding affinity for PA precursors. VviGST4, originally characterized as an anthocyanin-related GST, complemented both the anthocyanin and PA deposition, resembling the function of TT19. By contrast, VviGST1 only partially rescued the normal seed color. Furthermore the expression pattern of these VviGSTs showed that each of these genes could be associated with the accumulation of different flavonoids in specific tissues during grapevine fruit development. These results provide new insights into GST-mediated PA transport in grapevine and suggest that VviGSTs present

Effects of glutathione s-transferase (GST) M1 and T1 polymorphisms on antioxidant vitamins and oxidative stress-related parameters in Korean subclinical hypertensive subjects after kale juice (Brassica oleracea acephala) supplementation.

PubMed

Lee, Hye-Jin; Han, Jeong-Hwa; Park, Yoo Kyoung; Kang, Myung-Hee

2018-04-01

Glutathione s-transferase ( GST ) is involved in the formation of a multigene family comprising phase II detoxification enzymes, involved in the detoxification of reactive oxygen species. This study evaluated whether daily supplementation with kale juice could modulate levels of plasma antioxidant vitamins and oxidative stress-related parameters. We further examined whether this modulation was affected by combined GSTM1 and T1 polymorphisms. Totally, 84 subclinical hypertensive patients having systolic blood pressure (BP) over 130 mmHg or diastolic BP over 85 mmHg, received 300 mL of kale juice daily for 6 weeks. Blood samples were drawn before start of study and after completion of 6 weeks. After supplementation, we observed significant decrease in DNA damage and increase in erythrocyte catalase activity in all genotypes. Plasma level of vitamin C was significantly increased in the wild/null and double null genotypes. The plasma levels of β-carotene, erythrocyte glutathione peroxidase activity, and nitric oxide were increased only in the wild/null genotype after kale juice supplementation. The effect of kale juice was significantly greater in the GSTM1 null genotype and wild/null genotype groups, suggesting possibility of personalized nutritional prescriptions based on personal genetics.

Glutathione S - transferases class Pi and Mi and their significance in oncology.

PubMed

Marchewka, Zofia; Piwowar, Agnieszka; Ruzik, Sylwia; Długosz, Anna

2017-06-19

In this article the current data, which shows that glutathione S-transferases (GST) class Pi and Mi are interesting and promising biomarkers in acute and chronic inflammatory processes as well as in the oncology, were presented based on the review of the latest experimental and clinical studies. The article shows their characteristics, functions and participation (direct - GST Pi, indirect - GST Mi) in the regulation of signaling pathways of JNK kinases, which are involved in cell differentiation. Overexpression of glutathione S-transferases class Pi and Mi in many cancer cells plays a key role in cancer treatment, making them resistant to chemotherapy. GST isoenzymes are involved in the metabolism of various types of xenobiotics and endogenous substrates, so their altered expression in cancer tissues as well as in serum and urine could be an important potential marker of the cancer and an indicator of oxidative stress. The study shows the role of glutathione S-transferases in redox homeostasis of tumor cells and in the mechanism of resistance to anticancer drugs.

Mechanistic insights into EgGST1, a Mu class glutathione S-transferase from the cestode parasite Echinococcus granulosus.

PubMed

Arbildi, Paula; Turell, Lucía; López, Verónica; Alvarez, Beatriz; Fernández, Verónica

2017-11-01

Glutathione transferases (GSTs) comprise a major detoxification system in helminth parasites, displaying both catalytic and non-catalytic activities. The kinetic mechanism of these enzymes is complex and depends on the isoenzyme which is being analyzed. Here, we characterized the kinetic mechanism of rEgGST1, a recombinant form of a cytosolic GST from Echinococcus granulosus (EgGST1), which is related to the Mu-class of mammalian enzymes, using the canonical substrates glutathione (GSH) and 1-chloro-2,4-dinitrobenzene (CDNB). Initial rate and product inhibition studies were consistent with a steady-state random sequential mechanism, where both substrates are bound to the enzyme before the products are released. Kinetic constants were also determined (pH 6.5 and 30 °C). Moreover, rEgGST1 lowered the pK a of GSH from 8.71 ± 0.07 to 6.77 ± 0.08, and enzyme-bound GSH reacted with CDNB 1 × 10 5 times faster than free GSH at pH 7.4. Finally, the dissociation of the enzyme-GSH complex was studied by means of intrinsic fluorescence, as well as that of the complex with the anthelminth drug mebendazole. This is the first report on mechanistic issues related to a helminth parasitic GST. Copyright © 2017 Elsevier Inc. All rights reserved.

Pleiotropic Functions of Glutathione S-Transferase P

PubMed Central

Zhang, Jie; Grek, Christina; Ye, Zhi-Wei; Manevich, Yefim; Tew, Kenneth D.; Townsend, Danyelle M.

2016-01-01

Glutathione S-transferase P (GSTP) is one member of the GST superfamily that is prevalently expressed in mammals. Known to possess catalytic activity through deprotonating glutathione allowing formation of thioether bonds with electrophilic substrates, more recent discoveries have broadened our understanding of the biological roles of this protein. In addition to catalytic detoxification, other properties so far ascribed to GSTP include chaperone functions, regulation of nitric oxide pathways, regulation of a variety of kinase signaling pathways, and participation in the forward reaction of protein S-glutathionylation. The expression of GSTP has been linked with cancer and other human pathologies and more recently even with drug addiction. With respect to human health, polymorphic variants of GSTP may determine individual susceptibility to oxidative stress and/or be critical in the design and development of drugs that have used redox pathways as a discovery platform. PMID:24974181

GST Theta null genotype is associated with an increased risk for ulcerative colitis: a case-control study and meta-analysis of GST Mu and GST Theta polymorphisms in inflammatory bowel disease.

PubMed

Broekman, Mark M T J; Bos, Caro; Te Morsche, René H M; Hoentjen, Frank; Roelofs, Hennie M J; Peters, Wilbert H M; Wanten, Geert J A; de Jong, Dirk J

2014-10-01

Glutathione S-transferases (GSTs) are important in the detoxification of many compounds, including reactive oxygen species. Polymorphisms in GSTs resulting in a decreased enzyme activity might enhance the risk for inflammatory bowel disease by eliciting a state of oxidative stress. Previous case-control studies showed divergent results and were frequently limited in sample size; therefore we conducted a meta-analysis including results from our case-control study. For the case-control study, we genotyped 552 patients with Crohn's disease (CD), 223 patients with ulcerative colitis (UC) and 972 healthy controls by PCR for functional deletions in GST Mu and GST Theta. Both were not analyzed in recent genome-wide association studies. For the meta-analysis, PubMed, EMBASE and Web of Science were searched. In this meta-analysis, we show an enhanced susceptibility for UC in individuals with the GSTT1null genotype (odds ratio (OR) 2.27, 95% confidence interval (CI) 1.31-3.92). In our case-control study, a reduced risk for CD was seen with the GSTT1null genotype (OR 0.58, 95% CI 0.43-0.77); however, pooled analysis showed an OR of 1.67, 95% CI 0.81-3.45. In this meta-analysis, we showed an increased risk for UC in individuals with the GSTT1null genotype.

Effects of glutathione s-transferase (GST) M1 and T1 polymorphisms on antioxidant vitamins and oxidative stress-related parameters in Korean subclinical hypertensive subjects after kale juice (Brassica oleracea acephala) supplementation

PubMed Central

2018-01-01

BACKGROUND/OBJECTIVES Glutathione s-transferase (GST) is involved in the formation of a multigene family comprising phase II detoxification enzymes, involved in the detoxification of reactive oxygen species. This study evaluated whether daily supplementation with kale juice could modulate levels of plasma antioxidant vitamins and oxidative stress-related parameters. We further examined whether this modulation was affected by combined GSTM1 and T1 polymorphisms. SUBJECTS/METHODS Totally, 84 subclinical hypertensive patients having systolic blood pressure (BP) over 130 mmHg or diastolic BP over 85 mmHg, received 300 mL of kale juice daily for 6 weeks. Blood samples were drawn before start of study and after completion of 6 weeks. RESULTS After supplementation, we observed significant decrease in DNA damage and increase in erythrocyte catalase activity in all genotypes. Plasma level of vitamin C was significantly increased in the wild/null and double null genotypes. The plasma levels of β-carotene, erythrocyte glutathione peroxidase activity, and nitric oxide were increased only in the wild/null genotype after kale juice supplementation. CONCLUSIONS The effect of kale juice was significantly greater in the GSTM1 null genotype and wild/null genotype groups, suggesting possibility of personalized nutritional prescriptions based on personal genetics. PMID:29629028

An ethylene-responsive enhancer element is involved in the senescence-related expression of the carnation glutathione-S-transferase (GST1) gene.

PubMed

Itzhaki, H; Maxson, J M; Woodson, W R

1994-09-13

The increased production of ethylene during carnation petal senescence regulates the transcription of the GST1 gene encoding a subunit of glutathione-S-transferase. We have investigated the molecular basis for this ethylene-responsive transcription by examining the cis elements and trans-acting factors involved in the expression of the GST1 gene. Transient expression assays following delivery of GST1 5' flanking DNA fused to a beta-glucuronidase receptor gene were used to functionally define sequences responsible for ethylene-responsive expression. Deletion analysis of the 5' flanking sequences of GST1 identified a single positive regulatory element of 197 bp between -667 and -470 necessary for ethylene-responsive expression. The sequences within this ethylene-responsive region were further localized to 126 bp between -596 and -470. The ethylene-responsive element (ERE) within this region conferred ethylene-regulated expression upon a minimal cauliflower mosaic virus-35S TATA-box promoter in an orientation-independent manner. Gel electrophoresis mobility-shift assays and DNase I footprinting were used to identify proteins that bind to sequences within the ERE. Nuclear proteins from carnation petals were shown to specifically interact with the 126-bp ERE and the presence and binding of these proteins were independent of ethylene or petal senescence. DNase I footprinting defined DNA sequences between -510 and -488 within the ERE specifically protected by bound protein. An 8-bp sequence (ATTTCAAA) within the protected region shares significant homology with promoter sequences required for ethylene responsiveness from the tomato fruit-ripening E4 gene.

Pharmacogenetics of azathioprine in inflammatory bowel disease: A role for glutathione-S-transferase?

PubMed Central

Stocco, Gabriele; Pelin, Marco; Franca, Raffaella; De Iudicibus, Sara; Cuzzoni, Eva; Favretto, Diego; Martelossi, Stefano; Ventura, Alessandro; Decorti, Giuliana

2014-01-01

Azathioprine is a purine antimetabolite drug commonly used to treat inflammatory bowel disease (IBD). In vivo it is active after reaction with reduced glutathione (GSH) and conversion to mercaptopurine. Although this reaction may occur spontaneously, the presence of isoforms M and A of the enzyme glutathione-S-transferase (GST) may increase its speed. Indeed, in pediatric patients with IBD, deletion of GST-M1, which determines reduced enzymatic activity, was recently associated with reduced sensitivity to azathioprine and reduced production of azathioprine active metabolites. In addition to increase the activation of azathioprine to mercaptopurine, GSTs may contribute to azathioprine effects even by modulating GSH consumption, oxidative stress and apoptosis. Therefore, genetic polymorphisms in genes for GSTs may be useful to predict response to azathioprine even if more in vitro and clinical validation studies are needed. PMID:24707136

Inherited glutathione-S-transferase deficiency is a risk factor for pulmonary asbestosis.

PubMed

Smith, C M; Kelsey, K T; Wiencke, J K; Leyden, K; Levin, S; Christiani, D C

1994-09-01

Pulmonary diseases attributable to asbestos exposure constitute a significant public health burden, yet few studies have investigated potential genetic determinants of susceptibility to asbestos-related diseases. The glutathione-S-transferases are a family of conjugating enzymes that both catalyze the detoxification of a variety of potentially cytotoxic electrophilic agents and act in the generation of sulfadipeptide leukotriene inflammatory mediators. The gene encoding glutathione-S-transferase class mu (GSTM-1) is polymorphic; approximately 50% of Caucasian individuals have a homozygous deletion of this gene and do not produce functional enzyme. Glutathione-S-transferase mu (GST-mu) deficiency has been previously reported to be associated with smoking-induced lung cancer. We conducted a cross-sectional study to examine the prevalence of the homozygous deletion for the GSTM-1 gene in members of the carpentry trade occupationally exposed to asbestos. Members of the United Brotherhood of Carpenters and Joiners of America attending their 1991 National Union conference were invited to participate. Each participant was offered a chest X-ray and was asked to complete a comprehensive questionnaire and have their blood drawn. All radiographs were assessed for the presence of pneumoconiosis in a blinded fashion by a National Institute for Occupational Safety and Health-certified International Labor Office "B" reader. Individual GSTM-1 status was determined using polymerase chain reaction methods. Six hundred fifty-eight workers were studied. Of these, 80 (12.2%) had X-ray abnormalities associated with asbestos exposure. Individuals genetically deficient in GST-mu were significantly more likely to have radiographic evidence of nonmalignant asbestos-related disease than those who were not deficient (chi 2 = 5.0; P < 0.03).(ABSTRACT TRUNCATED AT 250 WORDS)

GLUTATHIONE S-TRANSFERASE THETA 1-1-DEPENDENT METABOLISM OF THE DISINFECTION BYPRODUCT BROMODICHLOROMETHANE

EPA Science Inventory

ABSTRACT
Bromodichloromethane (BDCM), a prevalent drinking water disinfection by-product, was previously shown to be mutagenic in Salmonella expressing glutathione S-transferase (GST) theta 1-1 (GST T1-1). In the present study, in vitro experiments were performed to study the...

Preparation of GST Fusion Proteins.

PubMed

Einarson, Margret B; Pugacheva, Elena N; Orlinick, Jason R

2007-04-01

INTRODUCTIONThis protocol describes the preparation of glutathione-S-transferase (GST) fusion proteins, which have had a wide range of applications since their introduction as tools for synthesis of recombinant proteins in bacteria. GST was originally selected as a fusion moiety because of several desirable properties. First and foremost, when expressed in bacteria alone, or as a fusion, GST is not sequestered in inclusion bodies (in contrast to previous fusion protein systems). Second, GST can be affinity-purified without denaturation because it binds to immobilized glutathione, which provides the basis for simple purification. Consequently, GST fusion proteins are routinely used for antibody generation and purification, protein-protein interaction studies, and biochemical analysis.

Methylenetetrahydrofolate reductase and glutathione S-tranferase gene polymorphisms in secondary mixed phenotype acute leukemia: a case report.

PubMed

Skoric, Dejan; Ivana, Joksic; Tanja, Radic; Jovana, Jakovljevic; Petar, Ivanovski; Tatjana, Simic

2014-04-01

Therapy-induced leukemia is a well-known clinical syndrome occurring as a late complication in patients treated with cytotoxic therapy. We herein present results of analysis of common gene polymorphisms in methylenetetrahydrofolate reductase (MTHFR) and glutathione S-transferase (GST) genes in a 10-year-old boy who developed very rare type of cancer, mixed phenotype acute leukemia, 6 years after treatment of acute lymphoblastic leukemia. Impairment in function of GST and MTHFR enzymes found in our patient may have contributed to the development of secondary mixed phenotype acute leukemia, although precise mechanism remains elusive.

Influence of glutathione S-transferase polymorphisms (GSTT1, GSTM1, GSTP1) on type-2 diabetes mellitus (T2D) risk in an endogamous population from north India.

PubMed

Mastana, Sarabjit S; Kaur, Antarpreet; Hale, Rachel; Lindley, Martin R

2013-12-01

Glutathione S-transferases (GSTs) belong to a group of multigene and multifunctional detoxification enzymes, which defend cells against a wide variety of toxic insults and oxidative stress. Oxidative stress leads to cellular dysfunction which contributes to the pathophysiology of diseases such as cancer, atherosclerosis, and diabetes mellitus. It is important to assess whether the glutathione S-Transferase (GSTT1, GSTM1 and GSTP1) genotypes are associated with type 2 diabetes mellitus as deletion polymorphisms have an impaired capability to counteract the oxidative stress which is a feature of diabetes. GSTT1, GSTM1 and GSTP1 gene polymorphisms were analysed in 321 patients and 309 healthy controls from an endogamous population from north India. An association analysis was carried out at two levels (a) individual genes and (b) their double and triple combinations. The proportion of GSTT1 and GSTM1 null genotypes was higher in diabetics compared to controls (GSTT1 30.8 vs. 21.0 %; GSTM1 49.5 vs. 27.2 %). The frequency of the null genotype at both loci was higher in diabetics (19.6 vs. 7.8 %) leading to an odds ratio of 2.90 (CI 1.76-4.78, P < 0.0001). At GSTP1locus, patients had a higher frequency of the V/V genotype (15.6 vs. 7.5 %) and significant susceptible odds ratio (2.56, CI 1.47-4.48, P < 0.001). A combination of null genotypes at GSTT1 and GSTM1 loci and V/V genotype of GSTP1 locus showed highest odds ratio (9.64, CI 1.53-60.63, P < 0.01). Overall this study highlights that GST genes may play an important role in the pathogenesis of type 2 diabetes. The risk is higher in individuals carrying more than one susceptible genotype at these loci. The potential role of GST polymorphisms as markers of susceptibility to type 2 diabetes needs further investigations in a larger number of patients and populations.

Neuroantibodies (NAB) in African-American Children: Associations with Gender, Glutathione-S-Transferase (GST)Pi Polymorphisms (SNP) and Heavy Metals

EPA Science Inventory

CONTACT (NAME ONLY): Hassan El-Fawal Abstract Details PRESENTATION TYPE: Platform or Poster CURRENT CATEGORY: Neurodegenerative Disease | Biomarkers | Neurotoxicity, Metals KEYWORDS: Autoantibodies, Glutathione-S-Transferase, DATE/TIME LAST MODIFIED: DATE/TIME SUBMITTED: Abs...

Assessment of cumulative evidence for the association between glutathione S-transferase polymorphisms and lung cancer: application of the Venice interim guidelines.

PubMed

Langevin, Scott M; Ioannidis, John P A; Vineis, Paolo; Taioli, Emanuela

2010-10-01

There is an overwhelming abundance of genetic association studies available in the literature, which can often be collectively difficult to interpret. To address this issue, the Venice interim guidelines were established for determining the credibility of the cumulative evidence. The objective of this report is to evaluate the literature on the association of common glutathione S-transferase (GST) variants (GSTM1 null, GSTT1 null and GSTP1 Ile105Val polymorphism) and lung cancer, and to assess the credibility of the associations using the newly proposed cumulative evidence guidelines. Information from the literature was enriched with an updated meta-analysis and a pooled analysis using data from the Genetic Susceptibility to Environmental Carcinogens database. There was a significant association between GSTM1 null and lung cancer for the meta-analysis (meta odds ratio=1.17, 95% confidence interval: 1.10-1.25) and pooled analysis (adjusted odds ratio=1.10, 95% confidence interval: 1.04-1.16), although substantial heterogeneity was present. No overall association between lung cancer and GSTT1 null or GSTP1 Ile105Val was found. When the Venice criteria was applied, cumulative evidence for all associations were considered 'weak', with the exception of East Asian carriers of the G allele of GSTP1 Ile105Val, which was graded as 'moderate' evidence. Despite the large amounts of studies, and several statistically significant summary estimates produced by meta-analyses, the application of the Venice criteria suggests extensive heterogeneity and susceptibility to bias for the studies on association of common genetic polymorphisms, such as with GST variants and lung cancer.

Molecular mimicry between cockroach and helminth glutathione S-transferases promotes cross-reactivity and cross-sensitization

USDA-ARS?s Scientific Manuscript database

The extensive similarities between helminth proteins and allergens are thought to contribute to helminth-driven allergic sensitization. We investigated the molecular and structural similarities between Bla g 5, a major glutathione-S transferase (GST) allergen of cockroaches, and the GST of Wucherer...

Association of Neuroantibodies(NAB) with Glutathione-S-Tranferase(GST) Isozyme Polymorphisms(SNP) in African-American Children with Heavy Metal Exposure

EPA Science Inventory

Polymorphisms in GST isozymes have implications in heavy metal accumulation, neurodegeneration, and immune-mediated disease. Blood cell DNA and sera from 131 African-American children were used to determine GST Pi [rs947895 (C>A), rs17593068 (G>T), rs6591256 (A>G), rs187...

Glutathione S-transferase Pi expression predicts response to adjuvant chemotherapy for stage C colon cancer: a matched historical control study.

PubMed

Jankova, Lucy; Robertson, Graham; Chan, Charles; Tan, King L; Kohonen-Corish, Maija; Fung, Caroline L-S; Clarke, Candice; Lin, Betty P C; Molloy, Mark; Chapuis, Pierre H; Bokey, Les; Dent, Owen F; Clarke, Stephen J

2012-05-28

This study examined the association between overall survival and Glutathione S-transferase Pi (GST Pi) expression and genetic polymorphism in stage C colon cancer patients after resection alone versus resection plus 5-fluourouracil-based adjuvant chemotherapy. Patients were drawn from a hospital registry of colorectal cancer resections. Those receiving chemotherapy after it was introduced in 1992 were compared with an age and sex matched control group from the preceding period. GST Pi expression was assessed by immunohistochemistry. Overall survival was analysed by the Kaplan-Meier method and Cox regression. From an initial 104 patients treated with chemotherapy and 104 matched controls, 26 were excluded because of non-informative immunohistochemistry, leaving 95 in the treated group and 87 controls. Survival did not differ significantly among patients with low GST Pi who did or did not receive chemotherapy and those with high GST Pi who received chemotherapy (lowest pair-wise p = 0.11) whereas patients with high GST Pi who did not receive chemotherapy experienced markedly poorer survival than any of the other three groups (all pair-wise p <0.01). This result was unaffected by GST Pi genotype. Stage C colon cancer patients with low GST Pi did not benefit from 5-fluourouracil-based adjuvant chemotherapy whereas those with high GST Pi did.

Identification of Glutathione S-Transferase (GST) Genes from a Dark Septate Endophytic Fungus (Exophiala pisciphila) and Their Expression Patterns under Varied Metals Stress

PubMed Central

Qiao, Qin; Liu, Lei; Wang, Jun-Ling; Cao, Guan-Hua; Li, Tao; Zhao, Zhi-Wei

2015-01-01

Glutathione S-transferases (GSTs) compose a family of multifunctional enzymes that play important roles in the detoxification of xenobiotics and the oxidative stress response. In the present study, twenty four GST genes from the transcriptome of a metal-tolerant dark septate endophyte (DSE), Exophiala pisciphila, were identified based on sequence homology, and their responses to various heavy metal exposures were also analyzed. Phylogenetic analysis showed that the 24 GST genes from E. pisciphila (EpGSTs) were divided into eight distinct classes, including seven cytosolic classes and one mitochondrial metaxin 1-like class. Moreover, the variable expression patterns of these EpGSTs were observed under different heavy metal stresses at their effective concentrations for inhibiting growth by 50% (EC50). Lead (Pb) exposure caused the up-regulation of all EpGSTs, while cadmium (Cd), copper (Cu) and zinc (Zn) treatments led to the significant up-regulation of most of the EpGSTs (p < 0.05 to p < 0.001). Furthermore, although heavy metal-specific differences in performance were observed under various heavy metals in Escherichia coli BL21 (DE3) transformed with EpGSTN-31, the over-expression of this gene was able to enhance the heavy metal tolerance of the host cells. These results indicate that E. Pisciphila harbored a diverse of GST genes and the up-regulated EpGSTs are closely related to the heavy metal tolerance of E. pisciphila. The study represents the first investigation of the GST family in E. pisciphila and provides a primary interpretation of heavy metal detoxification for E. pisciphila. PMID:25884726

Characterization of Affinity-Purified Isoforms of Acinetobacter calcoaceticus Y1 Glutathione Transferases

PubMed Central

Chee, Chin-Soon; Tan, Irene Kit-Ping; Alias, Zazali

2014-01-01

Glutathione transferases (GST) were purified from locally isolated bacteria, Acinetobacter calcoaceticus Y1, by glutathione-affinity chromatography and anion exchange, and their substrate specificities were investigated. SDS-polyacrylamide gel electrophoresis revealed that the purified GST resolved into a single band with a molecular weight (MW) of 23 kDa. 2-dimensional (2-D) gel electrophoresis showed the presence of two isoforms, GST1 (pI 4.5) and GST2 (pI 6.2) with identical MW. GST1 was reactive towards ethacrynic acid, hydrogen peroxide, 1-chloro-2,4-dinitrobenzene, and trans,trans-hepta-2,4-dienal while GST2 was active towards all substrates except hydrogen peroxide. This demonstrated that GST1 possessed peroxidase activity which was absent in GST2. This study also showed that only GST2 was able to conjugate GSH to isoproturon, a herbicide. GST1 and GST2 were suggested to be similar to F0KLY9 (putative glutathione S-transferase) and F0KKB0 (glutathione S-transferase III) of Acinetobacter calcoaceticus strain PHEA-2, respectively. PMID:24892084

Glutathione S-transferase Pi expression predicts response to adjuvant chemotherapy for stage C colon cancer: a matched historical control study

PubMed Central

2012-01-01

Background This study examined the association between overall survival and Glutathione S-transferase Pi (GST Pi) expression and genetic polymorphism in stage C colon cancer patients after resection alone versus resection plus 5-fluourouracil-based adjuvant chemotherapy. Methods Patients were drawn from a hospital registry of colorectal cancer resections. Those receiving chemotherapy after it was introduced in 1992 were compared with an age and sex matched control group from the preceding period. GST Pi expression was assessed by immunohistochemistry. Overall survival was analysed by the Kaplan-Meier method and Cox regression. Results From an initial 104 patients treated with chemotherapy and 104 matched controls, 26 were excluded because of non-informative immunohistochemistry, leaving 95 in the treated group and 87 controls. Survival did not differ significantly among patients with low GST Pi who did or did not receive chemotherapy and those with high GST Pi who received chemotherapy (lowest pair-wise p = 0.11) whereas patients with high GST Pi who did not receive chemotherapy experienced markedly poorer survival than any of the other three groups (all pair-wise p <0.01). This result was unaffected by GST Pi genotype. Conclusion Stage C colon cancer patients with low GST Pi did not benefit from 5-fluourouracil-based adjuvant chemotherapy whereas those with high GST Pi did. PMID:22639861

A model to environmental monitoring based on glutathione-S-transferase activity and branchial lesions in catfish

NASA Astrophysics Data System (ADS)

Neta, Raimunda Nonata Fortes Carvalho; Torres, Audalio Rebelo

2017-11-01

In this work, we validate the glutathione-S-transferase and branchial lesions as biomarkers in catfish Sciades herzbergii to obtain a predictive model of the environmental impact effects in a harbor of Brazil. The catfish were sampled from a port known to be contaminated with heavy metals and organic compounds and from a natural reserve in São Marcos Bay, Maranhão. Two biomarkers, hepatic glutathione S-transferase (GST) activity and branchial lesions were analyzed. The values for GST activity were modeled with the occurrence of branchial lesions by fitting a third order polynomial. Results from the mathematical model indicate that GST activity has a strong polynomial relationship with the occurrence of branchial lesions in both the wet and the dry seasons, but only at the polluted port site. Our mathematic model indicates that when the GST ceases to act, serious branchial lesions are observed in the catfish of the contaminated port area.

Glutathione-S-transferase profiles in the emerald ash borer, Agrilus planipennis.

PubMed

Rajarapu, Swapna Priya; Mittapalli, Omprakash

2013-05-01

The emerald ash borer, Agrilus planipennis Fairmaire is a recently discovered invasive insect pest of ash, Fraxinus spp. in North America. Glutathione-S-transferases (GST) are a multifunctional superfamily of enzymes which function in conjugating toxic compounds to less toxic and excretable forms. In this study, we report the molecular characterization and expression patterns of different classes of GST genes in different tissues and developmental stages plus their specific activity. Multiple sequence alignment of all six A. planipennis GSTs (ApGST-E1, ApGST-E2, ApGST-E3, ApGST-O1, ApGST-S1 and ApGST-μ1) revealed conserved features of insect GSTs and a phylogenetic analysis grouped the GSTs within the epsilon, sigma, omega and microsomal classes of GSTs. Real time quantitative PCR was used to study field collected samples. In larval tissues high mRNA levels for ApGST-E1, ApGST-E3 and ApGST-O1 were obtained in the midgut and Malpighian tubules. On the other hand, ApGST-E2 and ApGST-S1 showed high mRNA levels in fat body and ApGST-μ1 showed constitutive levels in all the tissues assayed. During development, mRNA levels for ApGST-E2 were observed to be the highest in feeding instars, ApGST-S1 in prepupal instars; while the others showed constitutive patterns in all the developmental stages examined. At the enzyme level, total GST activity was similar in all the tissues and developmental stages assayed. Results obtained suggest that A. planipennis is potentially primed with GST-driven detoxification to metabolize ash allelochemicals. To our knowledge this study represents the first report of GSTs in A. planipennis and also in the family of wood boring beetles. Copyright © 2013 Elsevier Inc. All rights reserved.

Glutathione S-transferase M1 and T1 gene polymorphisms with consumption of high fruit-juice and vegetable diet affect antioxidant capacity in healthy adults.

PubMed

Yuan, Linhong; Zhang, Ling; Ma, Weiwei; Zhou, Xin; Ji, Jian; Li, Nan; Xiao, Rong

2013-01-01

To our knowledge, no data have yet shown the combined effects of GSTM1/GSTT1 gene polymorphisms with high consumption of a fruit and vegetable diet on the body's antioxidant capacity. A 2-wk dietary intervention in healthy participants was conducted to test the hypothesis that the antioxidant biomarkers in individuals with different glutathione-S-transferases (GST) genotypes will be different in response to a high fruit-juice and vegetable diet. In our study, 24 healthy volunteers with different GST genotypes (12 GSTM1+/GSTT1+ and 12 GSTM1-/GSTT1- participants) consumed a controlled diet high in fruit-juice and vegetables for 2 wk. Blood and first-void urine specimens were obtained at baseline, 1-wk, and 2-wk intervals. The antioxidant capacity-related biomarkers in blood and urine were observed and recorded at the scheduled times. Erythrocyte GST and glutathione reductase (GR) activities response to a high fruit-juice and vegetable diet are GST genotype-dependent. Two weeks on the high fruit-juice and vegetable diet increased GST and GR activities in the GSTM1+/GSTT1+ group (P < 0.05 compared with baseline or GSTM1-/GSTT1- group), although no effects were observed on GST and GR activities in GSTM1-/GSTT1- participants. Dietary intervention increased total antioxidant capacity and decreased plasma malondialdehyde content in all participants (P < 0.05 compared with baseline), whereas GSTM1+/GSTT1+ participants respond more quickly to a high fruit-juice and vegetable diet than GSTM1-/GSTT1- participants. The diet intervention was effective in enhancing glutathione peroxidase and catalase activities in all participants (P < 0.05 compared with baseline), although there was no influence on erythrocyte superoxide dismutase activity (P > 0.05). The effects of a diet rich in fruit-juice and vegetables on antioxidant capacity were dependent on GSTM1/GSTT1 genotypes. Copyright © 2013 Elsevier Inc. All rights reserved.

Polymorphisms of Glutathione S-transferases Omega-1 among ethnic populations in China

PubMed Central

Fu, Songbo; Wu, Jie; Chen, Feng; Sun, Dianjun; Fu, Songbin

2008-01-01

Background Glutathione S-transferases (GSTs) is a genetic factor for many diseases and exhibits great diversities among various populations. We assessed association of the genotypes of Glutathione S-transferases Omega-1 (GSTO1) A140D with ethnicity in China. Results Peripheral blood samples were obtained from 1314 individuals from 14 ethnic groups. Polymorphisms of GSTO1 A140D were measured using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Logistic regression was employed to adjustment for regional factor. The frequency of GSTO1 140A allele was 15.49% in the total 14 ethnic populations. Compared to Han ethnic group, two ethnic populations were more likely to have AA or CA genotype [odds ratio (OR): 1.77, 95% confidence interval (95% CI): 1.05–2.98 for Uygur and OR: 1.78, 95% CI: 1.18–2.69 for Hui]. However, there were no statistically significant differences across 14 ethnic groups when region factor was adjusted. In Han ethnicity, region was significantly associated with AA or CA genotype. Han individuals who resided in North-west of China were more likely to have these genotypes than those in South of China (OR: 1.63, 95% CI: 1.21–2.20). Conclusion The prevalence of the GSTO1 140A varied significantly among different regional populations in China, which showed that geography played a more important role in the population differentiation for this allele than the ethnicity/race. PMID:18400112

The Nrf2/SKN-1-dependent glutathione S-transferase π homologue GST-1 inhibits dopamine neuron degeneration in a Caenorhabditis elegans model of manganism.

PubMed

Settivari, Raja; VanDuyn, Natalia; LeVora, Jennifer; Nass, Richard

2013-09-01

Exposure to high levels of manganese (Mn) results in a neurological condition termed manganism, which is characterized by oxidative stress, abnormal dopamine (DA) signaling, and cell death. Epidemiological evidence suggests correlations with occupational exposure to Mn and the development of the movement disorder Parkinson's disease (PD), yet the molecular determinants common between the diseases are ill-defined. Glutathione S-transferases (GSTs) of the class pi (GSTπ) are phase II detoxification enzymes that conjugate both endogenous and exogenous compounds to glutathione to reduce cellular oxidative stress, and their decreased expression has recently been implicated in PD progression. In this study we demonstrate that a Caenorhabditis elegans GSTπ homologue, GST-1, inhibits Mn-induced DA neuron degeneration. We show that GST-1 is expressed in DA neurons, Mn induces GST-1 gene and protein expression, and GST-1-mediated neuroprotection is dependent on the PD-associated transcription factor Nrf2/SKN-1, as a reduction in SKN-1 gene expression results in a decrease in GST-1 protein expression and an increase in DA neuronal death. Furthermore, decreases in gene expression of the SKN-1 inhibitor WDR-23 or the GSTπ-binding cell death activator JNK/JNK-1 result in an increase in resistance to the metal. Finally, we show that the Mn-induced DA neuron degeneration is independent of the dopamine transporter DAT, but is largely dependent on the caspases CED-3 and the novel caspase CSP-1. This study identifies a C. elegans Nrf2/SKN-1-dependent GSTπ homologue, cell death effectors of GSTπ-associated xenobiotic-induced pathology, and provides the first in vivo evidence that a phase II detoxification enzyme may modulate DA neuron vulnerability in manganism. Copyright © 2013 Elsevier Inc. All rights reserved.

Impact of CYP2E1, GSTA1 and GSTP1 gene variants on serum alpha glutathione S-transferase level in patients undergoing anaesthesia.

PubMed

Mikstacki, Adam; Skrzypczak-Zielinska, Marzena; Zakerska-Banaszak, Oliwia; Tamowicz, Barbara; Skibinska, Maria; Molinska-Glura, Marta; Szalata, Marlena; Slomski, Ryszard

2016-05-14

The serum glutathione S-transferase alpha (α-GST) concentration has been used as a marker of hepatic condition. After sevoflurane anaesthesia a mild impairment of hepatocellular integrity was observed. Genetic polymorphisms in CYP2E1, GSTA1 and GSTP1 genes, affecting enzymes activity, may possibly influence the hepatotoxic effect of sevoflurane. The aim of this study was to assess the influence of genetic polymorphism of CYP2E1, GSTA1 and GSTP1 genes on serum α-GST level in 86 unrelated patients representing ASA physical status I-II, undergoing laryngological surgery under general anaesthesia with sevoflurane. The serum samples from three perioperative time points were analyzed using ELISA. Genetic variants were detected by pyrosequencing and sequencing. Finally, the statistical associations between serum α-GST concentration and analyzed alleles of CYP2E1, GSTP1 and GSTA1 genes were estimated. The allele GSTA1*B (-567G, -69T, -52A) frequency was 0.43, whereas the alleles c.313G and c.341T of GSTP1 were identified with frequencies of 0.28 and 0.1 respectively. The -1053T allele of the CYP2E1 gene was observed with 0.01 frequency. We found serum α-GST concentrations in homozygous changes c.313A>G and c.341C>T of the GSTP1 gene significantly higher at the end of anaesthesia as compared with the levels at pre-anaesthetic and 24 h post-anaesthetic time points. Moreover, GSTA1 wild type genotype was associated with increased α-GST concentration at 24 h after the end of anaesthesia. GSTP1 gene polymorphism has an impact on the perioperative serum α-GST concentration in patients undergoing sevoflurane anaesthesia. A similar association, although not statistically significant exists between GSTA1 gene variants and perioperative serum α-GST level.

The relationship of glutathione-S-transferases copy number variation and indoor air pollution to symptoms and markers of respiratory disease.

PubMed

Hersoug, Lars-Georg; Brasch-Andersen, Charlotte; Husemoen, Lise Lotte Nystrup; Sigsgaard, Torben; Linneberg, Allan

2012-07-01

Exposure to particulate matter (PM) may induce inflammation and oxidative stress in the airways. Carriers of null polymorphisms of glutathione S-transferases (GSTs), which detoxify reactive oxygen species, may be particularly susceptible to the effects of PM. To investigate whether deletions of GSTM1 and GSTT1 modify the potential effects of exposure to indoor sources of PM on symptoms and objective markers of respiratory disease. We conducted a population-based, cross-sectional study of 3471 persons aged 18-69 years. Information about exposure to indoor sources of PM and respiratory symptoms was obtained by a self-administered questionnaire. In addition, measurements of lung function (spirometry) and fractional exhaled nitric oxide were performed. Copy number variation of GSTM1 and GSTT1 was determined by polymerase chain reaction-based assays. We found that none of the symptoms and objective markers of respiratory disease were significantly associated with the GST null polymorphisms. An increasing number of positive alleles of the GSTM1 polymorphism tended to be associated lower prevalence of wheeze, cough, and high forced expiratory volume in 1 s (FEV(1) ), but these trends were not statistically significant. Furthermore, we did not observe any statistically significant interactions between GST copy number variation and exposure to indoor sources of PM in relation to respiratory symptoms and markers. In this adult population, GST copy number variations were not significantly associated with respiratory outcomes and did not modify the effects of self-reported exposure to indoor sources of PM on respiratory outcomes. © 2011 Blackwell Publishing Ltd.

Development of enzyme-linked immunosorbent assay (ELISA) for glutathione S-transferase (GST-S) protein in the intertidal copepod Tigriopus japonicus and its application for environmental monitoring.

PubMed

Rhee, Jae-Sung; Kim, Bo-Mi; Jeong, Chang-Bum; Leung, Kenneth Mei Yee; Park, Gyung Soo; Lee, Jae-Seong

2013-11-01

To utilize the GST-S protein as a useful biomarker for environmental contamination, we developed a polyclonal antibody-based enzyme-linked immunosorbent assay (ELISA) in the intertidal copepod Tigriopus japonicus. Two polyclonal antibodies, TJ-GST-S1 and TJ-GST-S2, were raised against two TJ-GST-S synthetic peptides. Also a recombinant TJ-GST-S protein was purified as a standard for ELISA development. Each polyclonal antibody was tested by Western blot analysis and indirect ELISA. Of two polyclonal antibodies, TJ-GST-S2 ELISA was further employed due to its wide range of detection and the limit of specificity compared to those of TJ-GST-S1 ELISA system. After exposure to 4 metals (Ag, As, Cd, and Cu) to T. japonicus, the amount of TJ-GST-S protein was significantly elevated in a concentration-dependent manner. Also, TJ-GST-S protein was upregulated at relative high concentrations of B[α]P, PCB, and TBT. In this paper, we suggest that T. japonicas ELISA for TJ-GST-S2 is useful as a potential indicator system for marine contaminants. Copyright © 2013 Elsevier Ltd. All rights reserved.

Glutathione S-transferases in neonatal liver disease.

PubMed Central

Mathew, J.; Cattan, A. R.; Hall, A. G.; Hines, J. E.; Nelson, R.; Eastham, E.; Burt, A. D.

1992-01-01

AIMS: To investigate the distribution of alpha and pi class glutathione S-transferases (GST) in normal fetal, neonatal, and adult liver; and to examine changes in GST expression in neonatal liver disease. METHODS: alpha and pi class GST were immunolocalised in sections of formalin fixed liver tissue obtained from human fetuses (n = 21), neonates (n = 8), young children (n = 9) and adults (n = 10), and from neonates with extrahepatic biliary atresia (n = 15) and neonatal hepatitis (n = 12). Monospecific rabbit polyclonal antibodies were used with a peroxidase-antiperoxidase method. RESULTS: Expression of pi GST was localised predominantly within biliary epithelial cells of developing and mature bile ducts of all sizes from 16 weeks' gestation until term and in neonatal and adult liver. Coexpression of pi and alpha GST was seen in hepatocytes of developing fetal liver between 16 and 34 weeks' gestation. Although pi GST was seen in occasional hepatocytes up to six months of life, this isoenzyme was not expressed by hepatocytes in adult liver. By contrast, alpha GST continued to be expressed by hepatocytes in adult liver; this isoenzyme was also seen in some epithelial cells of large bile ducts in adult liver. No change was observed in the distribution of alpha GST in either neonatal hepatitis or extrahepatic biliary atresia. However, aberrant expression of pi GST was identified in hepatocytes of all but one case of extrahepatic biliary atresia but in only two cases of neonatal hepatitis. CONCLUSIONS: The phenotypic alterations noted in extrahepatic biliary atresia may result from the effect of cholate stasis. Evaluation of the pattern of pi and alpha GST distribution by immunohistochemical staining may provide valuable information in distinguishing between these two forms of neonatal liver disease. Images PMID:1401176

Aniline exposure associated with up-regulated transcriptional responses of three glutathione S-transferase Delta genes in Drosophila melanogaster.

PubMed

Chan, Wen-Chiao; Chien, Yi-Chih; Chien, Cheng-I

2015-03-01

Complex transcriptional profile of glutathione S-transferase Delta cluster genes occurred in the developmental process of the fruit fly Drosophila melanogaster. The purpose of this project was to quantify the expression levels of Gst Delta class genes altered by aniline exposure and to understand the relationship between aniline dosages and the variation of Gst Delta genes expressed in D. melanogaster. Using RT-PCR expression assays, the expression patterns of the transcript mRNAs of the glutathione S-transferase Delta genes were revealed and their expression levels were measured at eggs, larvae, pupae and adults. The adult stage was selected for further dose-response assays. After analysis, the results indicated that three Gst Delta genes (Gst D2, Gst D5 and Gst D6) were found to show a peak of up-regulated transcriptional response at 6-8h of exposure of aniline. Furthermore, the dose-response relationship of their induction levels within the dose regiments (from 1.2 to 2.0 μl/tube) had been measured. The expression patterns and annotations of these genes were discussed in the context. Copyright © 2015 Elsevier B.V. All rights reserved.

Purification and Biochemical Characterization of Glutathione S-Transferase from Down Syndrome and Normal Children Erythrocytes: A Comparative Study

ERIC Educational Resources Information Center

Hamed, Ragaa R.; Maharem, Tahany M.; Abdel-Meguid, Nagwa; Sabry, Gilane M.; Abdalla, Abdel-Monem; Guneidy, Rasha A.

2011-01-01

Down syndrome (DS) is the phenotypic manifestation of trisomy 21. Our study was concerned with the characterization and purification of glutathione S-transferase enzyme (GST) from normal and Down syndrome (DS) erythrocytes to illustrate the difference in the role of this enzyme in the cell. Glutathione S-transferase and glutathione (GSH) was…

Lymphocyte DNA damage and plasma antioxidant status in Korean subclinical hypertensive patients by glutathione S-transferase polymorphism

PubMed Central

Han, Jeong-Hwa; Lee, Hye-Jin; Choi, Hee Jeong; Yun, Kyung Eun

2017-01-01

BACKGROUND/OBJECTIVES Glutathione S-transferase (GST) forms a multigene family of phase II detoxification enzymes which are involved in the detoxification of xenobiotics by conjugating substances with glutathione. The aim of this study is to assess the antioxidative status and the degree of DNA damage in the subclinical hypertensive patients in Korea using glutathione S-transferase polymorphisms. SUBJECTS/METHODS We examined whether DNA damage and antioxidative status show a difference between GSTM1 or GSTT1 genotype in 227 newly diagnosed, untreated (systolic blood pressure (BP) ≥ 130 mmHg or diastolic BP ≥ 85 mmHg) subclinical hypertensive patients and 130 normotensive subjects (systolic BP < 120 mmHg and diastolic BP < 80 mmHg). From the blood of the subjects, the degree of the DNA damage in lymphocyte, the activities of erythrocyte superoxide dismutase, the catalase, and the glutathione peroxidase, the level of glutathione, plasma total radical-trapping antioxidant potential (TRAP), anti-oxidative vitamins, as well as plasma lipid profiles and conjugated diene (CD) were analyzed. RESULTS Of the 227 subjects studied, 68.3% were GSTM1 null genotype and 66.5% were GSTT1 null genotype. GSTM1 null genotype had an increased risk of hypertension (OR: 2.104, CI: 1.38-3.35), but no significant association in GSTT1 null genotype (OR 0.982, CI: 0.62-1.55). No difference in erythrocyte activities of superoxide dismutase, catalase, or glutathione peroxidase, and plasma TRAP, CD, lipid profiles, and GSH levels were observed between GSTM1 or GSTT1 genotype. Plasma levels of α-tocopherol increased significantly in GSTT1 wild genotype (P < 0.05); however, plasma level of β-carotene increased significantly in GSTT1 null genotype (P < 0.01). DNA damage assessed by the Comet assay was significantly higher in GSTM1 null genotype than wild genotype (P < 0.05). CONCLUSIONS These results confirm the association between GSTM1 null genotype and risk of hypertension as they suggest

Association of polymorphisms in glutathione S-transferase genes (GSTM1, GSTT1, GSTP1) with idiopathic azoospermia or oligospermia in Sichuan, China.

PubMed

Xiong, Da-Ke; Chen, Hong-Han; Ding, Xian-Ping; Zhang, Shao-Hong; Zhang, Jian-Hui

2015-01-01

The reported effects of the glutathione S-transferase (GSTs) genes (GSTM1, GSTT1, and GSTP1) on male factor infertility have been inconsistent and even contradictory. Here, we conducted a case-control study to investigate the association between functionally important polymorphisms in GST genes and idiopathic male infertility. The study group consisted of 361 men with idiopathic azoospermia, 118 men with idiopathic oligospermia, and 234 age-matched healthy fertile male controls. Genomic DNA was extracted from the peripheral blood, and analyzed by polymerase chain reaction and restriction fragment length polymorphism analysis. There was a significant association between the GSTP1 variant genotype (Ile/Val + Val/Val) with idiopathic infertility risk (odds ratio [OR]: 1.53; 95% confidence interval [CI]: 1.11-2.11; P = 0.009). Similarly, a higher risk of infertility was noted in individuals carrying a genotype combination of GSTT1-null and GSTP1 (Ile/Val + Val/Val) (OR: 2.17; 95% CI: 1.43-3.31; P = 0.0002). These results suggest an increased risk of the GSTP1 variant genotype (Ile/Val + Val/Val) for developing male factor infertility. Our findings also underrate the significance of the effect of GSTM1 and/or GSTT1 (especially the former) in modulating the risk of male infertility in males from Sichuan, Southwest China.

Glutathione S-Transferases Interact with AMP-Activated Protein Kinase: Evidence for S-Glutathionylation and Activation In Vitro

PubMed Central

Polge, Cécile; Ramirez, Sacnicte; Michelland, Sylvie; Sève, Michel; Vertommen, Didier; Rider, Mark; Lentze, Nicolas; Auerbach, Daniel; Schlattner, Uwe

2013-01-01

AMP-activated protein kinase (AMPK) is a cellular and whole body energy sensor with manifold functions in regulating energy homeostasis, cell morphology and proliferation in health and disease. Here we apply multiple, complementary in vitro and in vivo interaction assays to identify several isoforms of glutathione S-transferase (GST) as direct AMPK binding partners: Pi-family member rat GSTP1 and Mu-family members rat GSTM1, as well as Schistosoma japonicum GST. GST/AMPK interaction is direct and involves the N-terminal domain of the AMPK β-subunit. Complex formation of the mammalian GSTP1 and -M1 with AMPK leads to their enzymatic activation and in turn facilitates glutathionylation and activation of AMPK in vitro. GST-facilitated S-glutathionylation of AMPK may be involved in rapid, full activation of the kinase under mildly oxidative physiological conditions. PMID:23741294

Activity-Based Probes for Isoenzyme- and Site-Specific Functional Characterization of Glutathione S -Transferases

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stoddard, Ethan G.; Killinger, Bryan J.; Nair, Reji N.

Glutathione S-transferases (GSTs) comprise a highly diverse family of phase II drug metabolizing enzymes whose shared function is the conjugation of reduced glutathione to various endo- and xenobiotics. Although the conglomerate activity of these enzymes can be measured by colorimetric assays, measurement of the individual contribution from specific isoforms and their contribution to the detoxification of xenobiotics in complex biological samples has not been possible. For this reason, we have developed two activity-based probes that characterize active glutathione transferases in mammalian tissues. The GST active site is comprised of a glutathione binding “G site” and a distinct substrate binding “Hmore » site”. Therefore, we developed (1) a glutathione-based photoaffinity probe (GSH-ABP) to target the “G site”, and (2) a probe designed to mimic a substrate molecule and show “H site” activity (GST-ABP). The GSH-ABP features a photoreactive moiety for UV-induced covalent binding to GSTs and glutathione-binding enzymes. The GST-ABP is a derivative of a known mechanism-based GST inhibitor that binds within the active site and inhibits GST activity. Validation of probe targets and “G” and “H” site specificity was carried out using a series of competitors in liver homogenates. Herein, we present robust tools for the novel characterization of enzyme- and active site-specific GST activity in mammalian model systems.« less

Glutathione S-transferase mediates an ageing response to mitochondrial dysfunction

PubMed Central

Dancy, Beverley M.; Brockway, Nicole; Ramadasan-Nair, Renjini; Yang, Yoing; Sedensky, Margaret M.; Morgan, Philip G.

2016-01-01

To understand primary mitochondrial disease, we utilized a complex I-deficient Caenorhabditis elegans mutant, gas-1. These animals strongly upregulate the expression of gst-14 (encoding a glutathione S-transferase). Knockdown of gst-14 dramatically extends the lifespan of gas-1 and increases hydroxynonenal (HNE) modified mitochondrial proteins without improving complex I function. We observed no change in reactive oxygen species levels as measured by Mitosox staining, consistent with a potential role of GST-14 in HNE clearance. The upregulation of gst-14 in gas-1 animals is specific to the pharynx. These data suggest that an HNE-mediated response in the pharynx could be beneficial for lifespan extension in the context of complex I dysfunction in C. elegans. Thus, whereas HNE is typically considered damaging, our work is consistent with recent reports of its role in signaling, and that in this case, the signal is pro-longevity in a model of mitochondrial dysfunction. PMID:26704446

Expression Patterns of Glutathione Transferase Gene (GstI) in Maize Seedlings Under Juglone-Induced Oxidative Stress

PubMed Central

Sytykiewicz, Hubert

2011-01-01

Juglone (5-hydroxy-1,4-naphthoquinone) has been identified in organs of many plant species within Juglandaceae family. This secondary metabolite is considered as a highly bioactive substance that functions as direct oxidant stimulating the production of reactive oxygen species (ROS) in acceptor plants. Glutathione transferases (GSTs, E.C.2.5.1.18) represent an important group of cytoprotective enzymes participating in detoxification of xenobiotics and limiting oxidative damages of cellular macromolecules. The purpose of this study was to investigate the impact of tested allelochemical on growth and development of maize (Zea mays L.) seedlings. Furthermore, the effect of juglone-induced oxidative stress on glutathione transferase (GstI) gene expression patterns in maize seedlings was recorded. It was revealed that 4-day juglone treatment significantly stimulated the transcriptional activity of GstI in maize seedlings compared to control plants. By contrast, at the 6th and 8th day of experiments the expression gene responses were slightly lower as compared with non-stressed seedlings. Additionally, the specific gene expression profiles, as well as the inhibition of primary roots and coleoptile elongation were proportional to juglone concentrations. In conclusion, the results provide strong molecular evidence that allelopathic influence of juglone on growth and development of maize seedlings may be relevant with an induction of oxidative stress in acceptor plants. PMID:22174645

Monobromobimane occupies a distinct xenobiotic substrate site in glutathione S-transferase π

PubMed Central

Ralat, Luis A.; Colman, Roberta F.

2003-01-01

Monobromobimane (mBBr), functions as a substrate of porcine glutathione S-transferase π (GST π): The enzyme catalyzes the reaction of mBBr with glutathione. S-(Hydroxyethyl)bimane, a nonreactive analog of monobromobimane, acts as a competitive inhibitor with respect to mBBr as substrate but does not affect the reaction of GST π with another substrate, 1-chloro-2,4-dinitrobenzene (CDNB). In the absence of glutathione, monobromobimane inactivates GST π at pH 7.0 and 25°C as assayed using mBBr as substrate, with a lesser effect on the enzyme’s use of CDNB as substrate. These results indicate that the sites occupied by CDNB and mBBr are not identical. Inactivation is proportional to the incorporation of 2 moles of bimane/mole of subunit. Modification of GST π with mBBr does not interfere with its binding of 8-anilino-1-naphthalene sulfonate, indicating that this hydrophobic site is not the target of monobromobimane. S-Methylglutathione and S-(hydroxyethyl)bimane each yield partial protection against inactivation and decrease reagent incorporation, while glutathionyl-bimane protects completely against inactivation. Peptide analysis after trypsin digestion indicates that mBBr modifies Cys45 and Cys99 equally. Modification of Cys45 is reduced in the presence of S-methylglutathione, indicating that this residue is at or near the glutathione binding region. In contrast, modification of Cys99 is reduced in the presence of S-(hydroxyethyl)bimane, suggesting that this residue is at or near the mBBr xenobiotic substrate binding site. Modification of Cys99 can best be understood by reaction with monobromobimane while it is bound to its xenobiotic substrate site in an alternate orientation. These results support the concept that glutathione S-transferase accomplishes its ability to react with a diversity of substrates in part by harboring distinct xenobiotic substrate sites. PMID:14573868

Monobromobimane occupies a distinct xenobiotic substrate site in glutathione S-transferase pi.

PubMed

Ralat, Luis A; Colman, Roberta F

2003-11-01

Monobromobimane (mBBr), functions as a substrate of porcine glutathione S-transferase pi (GST pi): The enzyme catalyzes the reaction of mBBr with glutathione. S-(Hydroxyethyl)bimane, a nonreactive analog of monobromobimane, acts as a competitive inhibitor with respect to mBBr as substrate but does not affect the reaction of GST pi with another substrate, 1-chloro-2,4-dinitrobenzene (CDNB). In the absence of glutathione, monobromobimane inactivates GST pi at pH 7.0 and 25 degrees C as assayed using mBBr as substrate, with a lesser effect on the enzyme's use of CDNB as substrate. These results indicate that the sites occupied by CDNB and mBBr are not identical. Inactivation is proportional to the incorporation of 2 moles of bimane/mole of subunit. Modification of GST pi with mBBr does not interfere with its binding of 8-anilino-1-naphthalene sulfonate, indicating that this hydrophobic site is not the target of monobromobimane. S-Methylglutathione and S-(hydroxyethyl)bimane each yield partial protection against inactivation and decrease reagent incorporation, while glutathionyl-bimane protects completely against inactivation. Peptide analysis after trypsin digestion indicates that mBBr modifies Cys45 and Cys99 equally. Modification of Cys45 is reduced in the presence of S-methylglutathione, indicating that this residue is at or near the glutathione binding region. In contrast, modification of Cys99 is reduced in the presence of S-(hydroxyethyl)bimane, suggesting that this residue is at or near the mBBr xenobiotic substrate binding site. Modification of Cys99 can best be understood by reaction with monobromobimane while it is bound to its xenobiotic substrate site in an alternate orientation. These results support the concept that glutathione S-transferase accomplishes its ability to react with a diversity of substrates in part by harboring distinct xenobiotic substrate sites.

Inhibition of the recombinant cattle tick Rhipicephalus (Boophilus) annulatus glutathione S-transferase.

PubMed

Guneidy, Rasha A; Shahein, Yasser E; Abouelella, Amira M K; Zaki, Eman R; Hamed, Ragaa R

2014-09-01

Rhipicephalus (Boophilus) annulatus is a bloodsucking ectoparasite that causes severe production losses in the cattle industry. This study aims to evaluate the in vitro effects of tannic acid, hematin (GST inhibitors) and different plant extracts (rich in tannic acid) on the activity of the recombinant glutathione S-transferase enzyme of the Egyptian cattle tick R. annulatus (rRaGST), in order to confirm their ability to inhibit the parasitic essential detoxification enzyme glutathione S-transferase. Extraction with 70% ethanol of Hibiscus cannabinus (kenaf flowers), Punica granatum (red and white pomegranate peel), Musa acuminata (banana peel) (Musaceae), Medicago sativa (alfalfa seeds), Tamarindus indicus (seed) and Cuminum cyminum (cumin seed) were used to assess: (i) inhibitory capacities of rRaGST and (ii) their phenolic and flavonoid contents. Ethanol extraction of red pomegranate peel contained the highest content of phenolic compounds (29.95mg gallic acid/g dry tissue) compared to the other studied plant extracts. The highest inhibition activities of rRaGST were obtained with kenaf and red pomegranate peel (P. granatum) extracts with IC50 values of 0.123 and 0.136mg dry tissue/ml, respectively. Tannic acid was the more effective inhibitor of rRaGST with an IC50 value equal to 4.57μM compared to delphinidine-HCl (IC50=14.9±3.1μM). Gossypol had a weak inhibitory effect (IC50=43.7μM), and caffeic acid had almost no effect on tick GST activity. The IC50 values qualify ethacrynic acid as a potent inhibitor of rRaGST activity (IC50=0.034μM). Cibacron blue and hematin showed a considerable inhibition effect on rRaGST activity, and their IC50 values were 0.13μM and 7.5μM, respectively. The activity of rRaGST was highest for CDNB (30.2μmol/min/mg protein). The enzyme had also a peroxidatic activity (the specific activity equals 26.5μmol/min/mg protein). Both tannic acid and hematin inhibited rRaGST activity non-competitively with respect to GSH and

Serum glutathione S-transferase Pi as predictor of the outcome and acute kidney injury in premature newborns.

PubMed

Stojanović, Vesna D; Barišić, Nenad A; Radovanović, Tanja D; Kovač, Nataša B; Djuran, Jelena D; Antić, Amira Peco E; Doronjski, Aleksandra D

2018-07-01

The incidence of acute kidney injury (AKI) among the neonates treated at the Neonatal Intensive Care Unit is high with high mortality rates. Glutathione S-transferase (GST) class Pi plays an important role in the protection of cells from cytotoxic and oncogenic agents. The aim of the study was to examine whether the levels of serum glutathione S-transferase Pi (GST Pi) determined after birth have any predictive value for the outcome and development of AKI in premature neonates. The prospective study included 36 premature neonates. The data about morbidity was gathered for all the neonates included in the study. The blood samples were taken in the first 6 h of life and GST Pi levels were measured. The mean values and standard deviations of GST Pi among the neonates who died and who survived were 1.904 ± 0.4535 vs 1.434 ± 0.444 ng/ml (p = 0.0128). Logistic regression revealed a statistically significant, positive correlation between GST Pi levels and death (p = 0.0180, OR7.5954; CI 1.4148-40.7748).The mean value of GST Pi levels in the neonates with AKI was higher than in neonates without AKI (p = 0.011). The conclusion of our study is that high levels of serum GST Pi in the first 6 h after birth are associated with an increased mortality and development of AKI in prematurely born neonates.

Glutathione-s-transferase-pi expression in early breast cancer: association with outcome and response to chemotherapy.

PubMed

Arun, Banu K; Granville, Laura A; Yin, Guosheng; Middleton, Lavinia P; Dawood, Shaheenah; Kau, Shu-Wan; Kamal, Arif; Hsu, Limin; Hortobagyi, Gabriel N; Sahin, Aysegul A

2010-06-01

Glutathione-S-transferase-pi (GST-pi) is a detoxification enzyme expressed in breast cancer; however its involvement in chemotherapy sensitivity and prognosis is not well understood. We evaluated the expression of GSTpi and its predictive role of chemotherapy response. Breast tumor samples from 166 patients at stage I/II of the disease were immunostained for GST-pi, and the expression was 96 %. There was a trend toward improved disease-free survival with high GST-pi expression (p =.09). There was a statistically non-significant association between high GST-pi expression and improved outcome with adjuvant chemotherapy (p =.055). Further studies should evaluate the role of GST-pi expression in relation to response to different chemotherapies.

Identification of Small-Molecule Frequent Hitters of Glutathione S-Transferase-Glutathione Interaction.

PubMed

Brenke, Jara K; Salmina, Elena S; Ringelstetter, Larissa; Dornauer, Scarlett; Kuzikov, Maria; Rothenaigner, Ina; Schorpp, Kenji; Giehler, Fabian; Gopalakrishnan, Jay; Kieser, Arnd; Gul, Sheraz; Tetko, Igor V; Hadian, Kamyar

2016-07-01

In high-throughput screening (HTS) campaigns, the binding of glutathione S-transferase (GST) to glutathione (GSH) is used for detection of GST-tagged proteins in protein-protein interactions or enzyme assays. However, many false-positives, so-called frequent hitters (FH), arise that either prevent GST/GSH interaction or interfere with assay signal generation or detection. To identify GST-FH compounds, we analyzed the data of five independent AlphaScreen-based screening campaigns to classify compounds that inhibit the GST/GSH interaction. We identified 53 compounds affecting GST/GSH binding but not influencing His-tag/Ni(2+)-NTA interaction and general AlphaScreen signals. The structures of these 53 experimentally identified GST-FHs were analyzed in chemoinformatic studies to categorize substructural features that promote interference with GST/GSH binding. Here, we confirmed several existing chemoinformatic filters and more importantly extended them as well as added novel filters that specify compounds with anti-GST/GSH activity. Selected compounds were also tested using different antibody-based GST detection technologies and exhibited no interference clearly demonstrating specificity toward their GST/GSH interaction. Thus, these newly described GST-FH will further contribute to the identification of FH compounds containing promiscuous substructures. The developed filters were uploaded to the OCHEM website (http://ochem.eu) and are publicly accessible for analysis of future HTS results. © 2016 Society for Laboratory Automation and Screening.

Characterization of glutathione S-transferase and its immunodiagnostic potential for detecting Taenia multiceps.

PubMed

Sun, Ying; Wang, Yu; Huang, Xing; Gu, Xiaobing; Lai, Weimin; Peng, Xuerong; Yang, Guangyou

2017-08-15

Taenia multiceps is a widespread zoonotic tapeworm parasite which infects cloven-hoofed animals around the world. Animal infection with Coenurus cerebralis, the coenurus larvae of T. multiceps (Tm), is often fatal, which is a major cause of economic losses in stockbreeding. This study amplified the glutathione S-transferase (GST) gene from the total RNA of C. cerebralis. The resulting protein, Tm-GST, consisted of 201 amino acids, and had a predicted molecular mass of 23.1kDa. Its amino acid sequence shares 77.61% similarity with Echinococcus granulosus GST. Recombinant Tm-GST (rTm-GST) was expressed in Escherichia coli. The protein reacted with serum from goats infected with T. multiceps. Immunofluorescence signals indicated that Tm-GST was largely localized in the parenchymatous area of adult T. multiceps; in addition, it was also apparent in the coenurus. An enzyme-linked immunosorbent assay based on rTm-GST showed specificity of 92.8% (13/14) and sensitivity of 90% (18/20) in detecting anti-GST antibodies in serum from naturally infected animals. This study suggests that Tm-GST has the potential to be used as a diagnostic antigen for Coenurosis. Copyright © 2017. Published by Elsevier B.V.

Optimization and revision of the production process of the Necator americanus glutathione S-transferase 1 (Na-GST-1), the lead hookworm vaccine recombinant protein candidate

PubMed Central

Curti, Elena; Seid, Christopher A; Hudspeth, Elissa; Center, Lori; Rezende, Wanderson; Pollet, Jeroen; Kwityn, Cliff; Hammond, Molly; Matsunami, Rise K; Engler, David A; Hotez, Peter J; Elena Bottazzi, Maria

2014-01-01

Infection by the human hookworm Necator americanus is a leading cause of anemia and disability in the developing countries of Africa, Asia, and the Americas. In order to prevent childhood hookworm disease in resource poor settings, a recombinant vaccine is under development by the Sabin Vaccine Institute and Texas Children’s Hospital Center for Vaccine Development, a Product Development Partnership (PDP). Previously, we reported on the expression and purification of a highly promising hookworm vaccine candidate, Na-GST-1, an N. americanus glutathione s-transferase expressed in Pichia pastoris (yeast), which led to production of 1.5 g of 95% pure recombinant protein at a 20L scale.1, 2, 3 This yield and purity of Na-GST-1 was sufficient for early pilot manufacturing and initial phase 1 clinical testing. However, based on the number of doses which would be required to allow mass vaccination and a potential goal to deliver a vaccine as inexpensively as possible, a higher yield of expression of the recombinant antigen at the lowest possible cost is highly desirable. Here we report on modifications to the fermentation (upstream process) of the antigen expressed in P. pastoris, and to the purification (downstream process) of the recombinant protein that allowed for a 2–3-fold improvement in the final yield of Na-GST-1 purified protein. The major improvements included upstream process changes such as the addition of a sorbitol pulse and co-feed during methanol induction as well as an extension of the induction stage to approximately 96 hours; downstream process changes included modifying the UFDF to flat sheet with a 10 kDa Molecular Weight cut-off (MWCO), adjusting the capacity of an ion-exchange chromatography step utilizing a gradient elution as opposed to the original step elution, and altering the hydrophobic interaction chromatography conditions. The full process, as well as the purity and stability profiles of the target Na-GST-1, and its formulation on

Analyses of Genetic Variations of Glutathione S-Transferase Mu1 and Theta1 Genes in Bangladeshi Tannery Workers and Healthy Controls.

PubMed

Akther, Jobaida; Ebihara, Akio; Nakagawa, Tsutomu; Islam, Laila N; Suzuki, Fumiaki; Hosen, Md Ismail; Hossain, Mahmud; Nabi, A H M Nurun

2016-01-01

Glutathione S-transferases (GSTs) belong to a group of multigene detoxification enzymes, which defend cells against oxidative stress. Tannery workers are at risk of oxidative damage that is usually detoxified by GSTs. This study investigated the genotypic frequencies of GST Mu1 (GSTM1) and GST Theta1 (GSTT1) in Bangladeshi tannery workers and healthy controls followed by their status of oxidative stress and total GST activity. Of the 188 individuals, 50.0% had both GSTM1 and GSTT1 (+/+), 12.2% had GSTM1 (+/-), 31.4% had GSTT1 (-/+) alleles, and 6.4% had null genotypes (-/-) with respect to both GSTM1 and GSTT1 alleles. Among 109 healthy controls, 54.1% were double positive, 9.2% had GSTM1 allele, 32.1% had GSTT1 allele, and 4.6% had null genotypes. Out of 79 tannery workers, 44.3% were +/+, 16.8% were +/-, 30.5% were -/+, and 8.4% were -/-. Though the polymorphic genotypes or allelic variants of GSTM1 and GSTT1 were distributed among the study subjects with different frequencies, the differences between the study groups were not statistically significant. GST activity did not vary significantly between the two groups and also among different genotypes while level of lipid peroxidation was significantly higher in tannery workers compared to controls irrespective of their GST genotypes.

Analyses of Genetic Variations of Glutathione S-Transferase Mu1 and Theta1 Genes in Bangladeshi Tannery Workers and Healthy Controls

PubMed Central

Akther, Jobaida; Ebihara, Akio; Nakagawa, Tsutomu; Islam, Laila N.; Suzuki, Fumiaki; Hosen, Md. Ismail; Hossain, Mahmud; Nabi, A. H. M. Nurun

2016-01-01

Glutathione S-transferases (GSTs) belong to a group of multigene detoxification enzymes, which defend cells against oxidative stress. Tannery workers are at risk of oxidative damage that is usually detoxified by GSTs. This study investigated the genotypic frequencies of GST Mu1 (GSTM1) and GST Theta1 (GSTT1) in Bangladeshi tannery workers and healthy controls followed by their status of oxidative stress and total GST activity. Of the 188 individuals, 50.0% had both GSTM1 and GSTT1 (+/+), 12.2% had GSTM1 (+/−), 31.4% had GSTT1 (−/+) alleles, and 6.4% had null genotypes (−/−) with respect to both GSTM1 and GSTT1 alleles. Among 109 healthy controls, 54.1% were double positive, 9.2% had GSTM1 allele, 32.1% had GSTT1 allele, and 4.6% had null genotypes. Out of 79 tannery workers, 44.3% were +/+, 16.8% were +/−, 30.5% were −/+, and 8.4% were −/−. Though the polymorphic genotypes or allelic variants of GSTM1 and GSTT1 were distributed among the study subjects with different frequencies, the differences between the study groups were not statistically significant. GST activity did not vary significantly between the two groups and also among different genotypes while level of lipid peroxidation was significantly higher in tannery workers compared to controls irrespective of their GST genotypes. PMID:27294127

Isolation and purification of glutathione S-transferases from Brachionus plicatilis and B. calyciflorus (Rotifera).

PubMed

Bowman, B P; Snell, T W; Cochrane, B J

1990-01-01

1. The enzyme glutathione S-transferase (GST), a critical element in xenobiotic metabolism, was isolated from the marine rotifer Brachionus plicatilis and its freshwater congener B. calyciflorus. 2. In B. plicatilis, GST comprised 4.2% of cytosolic protein and was present as three separate isozymes with mol. wts 30,000, 31,400 and 33,700. Specific activity of crude homogenates was 56 nmol min-1 mg-1 protein, while that of affinity chromatography purified GST was 1850. 3. In B. calyciflorus, GST was present as two isozymes with mol. wts of 26,300 and 28,500, representing 1.0% of cytosolic protein. Crude GST specific activity was 1750 nmol min-1 mg-1 protein and purified was 72,400. 4. Rotifer GSTs are unusual because they are monomers whereas all other animals thus far investigated posses dimeric GSTs.

Molecular cloning and expression of five glutathione S-transferase (GST) genes from Banana (Musa acuminata L. AAA group, cv. Cavendish).

PubMed

Wang, Zhuo; Huang, Suzhen; Jia, Caihong; Liu, Juhua; Zhang, Jianbin; Xu, Biyu; Jin, Zhiqiang

2013-09-01

Three tau class MaGSTs responded to abiotic stress, MaGSTF1 and MaGSTL1 responded to signaling molecules, they may play an important role in the growth of banana plantlet. Glutathione S-transferases (GST) are multifunctional detoxification enzymes that participate in a variety of cellular processes, including stress responses. In this study, we report the molecular characteristics of five GST genes (MaGSTU1, MaGSTU2, MaGSTU3, MaGSTF1 and MaGSTL1) cloned from banana (Musa acuminate L. AAA group, cv. Cavendish) using a RACE-PCR-based strategy. The predicted molecular masses of these GSTs range from 23.4 to 27.7 kDa and their pIs are acidic. At the amino acid level, they share high sequence similarity with GSTs in the banana DH-Pahang (AA group) genome. Phylogenetic analysis showed that the deduced amino acid sequences of MaGSTs also have high similarity to GSTs of other plant species. Expression analysis by semi-quantitative RT-PCR revealed that these genes are differentially expressed in various tissues. In addition, their expression is regulated by various stress conditions, including exposure to signaling molecules, cold, salinity, drought and Fusarium oxysporum f specialis(f. Sp) cubense Tropical Race 4 (Foc TR4) infection. The expression of the tau class MaGSTs (MaGSTU1, MaGSTU2 and MaGSTU3) mainly responded to cold, salinity and drought while MaGSTF1 and MaGSTL1 expressions were upregulated by signaling molecules. Our findings suggest that MaGSTs play a key role in both development and abiotic stress responses.

Association of ACE, FABP2 and GST genes polymorphism with essential hypertension risk among a North Indian population.

PubMed

Abbas, Shania; Raza, Syed Tasleem; Chandra, Anu; Rizvi, Saliha; Ahmed, Faisal; Eba, Ale; Mahdi, Farzana

2015-01-01

Hypertension has a multi-factorial background based on genetic and environmental interactive factors. ACE, FABP2 and GST genes have been suggested to be involved in the development of hypertension. However, the results have been inconsistent. The present study was carried out to investigate the association of ACE (rs4646994), FABP2 (rs1799883) and GST (GSTM1 null or positive genotype and GSTT1 null or positive genotype) genes polymorphism with essential HTN cases and controls. This study includes 138 essential hypertension (HTN) patients and 116 age-, sex- and ethnicity-matched control subjects. GST (GSTM1 null or positive genotype and GSTT1 null or positive genotype) genes polymorphisms were evaluated by multiplex PCR, ACE (rs4646994) gene polymorphisms by PCR and FABP2 (rs1799883) gene polymorphisms by PCR-RFLP method. Significant differences were obtained in the frequencies of ACE DD, II genotype (p = 0.006, 0.003), GSTT1 null, GSTM1 positive genotype (p = 0.048, 0.010) and FABP2 Ala54/Ala54 genotype (p = 0.049) between essential HTN cases and controls. It is concluded that ACE (rs 4646994), FABP2 (rs1799883) and GST (GSTM1 null or positive genotype and GSTT1 null or positive genotype) genes polymorphism are associated with HTN. Further investigation with a larger sample size may be required to validate this study.

Glutathione S-transferase-encoding gene as a potential probe for environmental bacterial isolates capable of degrading polycyclic aromatic hydrocarbons.

PubMed Central

Lloyd-Jones, G; Lau, P C

1997-01-01

Homologs of the glutathione S-transferase (GST)-encoding gene were identified in a collection of aromatic hydrocarbon-degrading Sphingomonas spp. isolated from New Zealand, Antarctica, and the United States by using PCR primers designed from the GST-encoding gene of Sphingomonas paucimobilis EPA505. Sequence analysis of PCR fragments generated from these isolates and of the GST gene amplified from DNA extracted from polycyclic aromatic hydrocarbon (PAH)-contaminated soil revealed a high degree of conservation, which may make the GST-encoding gene a potentially useful marker for PAH-degrading bacteria. PMID:9251217

Glutathion-S-Transferase P1 polymorphisms association with broncopulmonary dysplasia in preterm infants

PubMed Central

Karagianni, P; Rallis, D; Fidani, L; Porpodi, M; Kalinderi, K; Tsakalidis, C; Nikolaidis, N

2013-01-01

Background: Oxidative stress, characterized by the excretion of pre-oxidative and anti-oxidative proteases, has a key role in the pathogenesis of bronchopulmonary dysplasia (BPD). One of the many host anti-oxidant enzymes is glutathione-S-transferase P1 (GSTP1), with three polymorphic alleles having been identified: homozygous ile, heterozygous ile/val and homozygous val isomorph. The aim of this study was to examine the genetic predisposition to BPD in the GSTP1 polymorphisms. Methods: A prospective case-control study was carried out in the 2nd Neonatal Intensive Care Unit of Aristotle University in Thessaloniki, Greece during 2008. The genetic polymorphisms of GSTP1 in 28 preterms <32 weeks gestational age (GA) with BPD compared to 74 controls (33 preterms without BPD and 41 healthy terms) were examined. Results: The homozygous ile isomorph was predominant in all groups (preterms with BPD: 82%, preterms without BPD: 70%, healthy terms: 78%), followed by the heterozygous ile/val (14%, 18% and 20% respectively) and the homozygous val isomorph (4%, 12% and 2% respectively). The homozygous ile isomorph was also identified in the majority of preterms with mild (80%), moderate (100%) and severe (73%) BPD. The GSTP1 genetic distribution did not differ between the groups and GSTP1 polymorphisms were not associated with the severity of BPD. Conclusions: This study could not confirm an association between GSTP1 polymorphisms and the development of BPD or the severity of the disease. PMID:25031518

Glutathion-S-Transferase P1 polymorphisms association with broncopulmonary dysplasia in preterm infants.

PubMed

Karagianni, P; Rallis, D; Fidani, L; Porpodi, M; Kalinderi, K; Tsakalidis, C; Nikolaidis, N

2013-10-01

Oxidative stress, characterized by the excretion of pre-oxidative and anti-oxidative proteases, has a key role in the pathogenesis of bronchopulmonary dysplasia (BPD). One of the many host anti-oxidant enzymes is glutathione-S-transferase P1 (GSTP1), with three polymorphic alleles having been identified: homozygous ile, heterozygous ile/val and homozygous val isomorph. The aim of this study was to examine the genetic predisposition to BPD in the GSTP1 polymorphisms. A prospective case-control study was carried out in the 2nd Neonatal Intensive Care Unit of Aristotle University in Thessaloniki, Greece during 2008. The genetic polymorphisms of GSTP1 in 28 preterms <32 weeks gestational age (GA) with BPD compared to 74 controls (33 preterms without BPD and 41 healthy terms) were examined. The homozygous ile isomorph was predominant in all groups (preterms with BPD: 82%, preterms without BPD: 70%, healthy terms: 78%), followed by the heterozygous ile/val (14%, 18% and 20% respectively) and the homozygous val isomorph (4%, 12% and 2% respectively). The homozygous ile isomorph was also identified in the majority of preterms with mild (80%), moderate (100%) and severe (73%) BPD. The GSTP1 genetic distribution did not differ between the groups and GSTP1 polymorphisms were not associated with the severity of BPD. This study could not confirm an association between GSTP1 polymorphisms and the development of BPD or the severity of the disease.

Differential expression of two glutathione S-transferases identified from the American dog tick, Dermacentor variabilis.

PubMed

Dreher-Lesnick, S M; Mulenga, A; Simser, J A; Azad, A F

2006-08-01

Reciprocal signalling and gene expression play a cardinal role during pathogen-host molecular interactions and are prerequisite to the maintenance of balanced homeostasis. Gene expression repertoire changes during rickettsial infection and glutathione-S-transferases (GSTs) were among the genes found up-regulated in Rickettsia-infected Dermacentor variabilis. GSTs are well known to play an important part in cellular stress responses in the host. We have cloned two full-length GSTs from D. variabilis (DvGST1 and DvGST2). Comparison of these two DvGST molecules with those of other species indicate that DvGST1 is related to the mammalian class theta and insect class delta GSTs, while DvGST2 does not seem to fall in the same family. Northern blotting analyses revealed differential expression patterns, where DvGST1 and DvGST2 transcripts are found in the tick gut, with DvGST2 transcripts also present in the ovaries. Both DvGST transcripts are up-regulated upon tick feeding. Challenge of fed adult ticks with Escherichia coli injection showed decreased transcript amounts compared with ticks injected with phosphate-buffered saline (sham) and naïve ticks.

Glutathione-S-transferases pi, alpha, mu and mdr1 mRNA expression in normal lymphocytes and chronic lymphocytic leukemia.

PubMed

Marie, J P; Simonin, G; Legrand, O; Delmer, A; Faussat, A M; Lewis, A D; Sikic, B I; Zittoun, R

1995-10-01

Chronic B cell lymphoproliferative disorders are frequently sensitive to alkylating agents. To assess the glutathione-S-transferases (GSTs) gene expression in B tumoral lymphocytes, possibly responsible for this sensitivity, we developed a sensitive RT-PCR assay for the three isoenzymes GST pi, GST mu and GST alpha mRNA. Normal B and T lymphocytes from 11 blood donors were separated by magnetic beads and tested with this assay. The GST pi was the most abundant transferase, and was detected in all B and T cell samples. GST mu was undetectable ('null' phenotype) in 6/11 normal donors, either in B or T cells. GST alpha was very stable from donor to donor, and was highly correlated between B and T cells of the same individual (P < 0.0001). There is no correlation between the three isoenzymes, and between each isoenzyme and mdr1 gene expression. Twenty-three B lymphoproliferative disorders (20 B-CLL, 3 CD5- chronic lymphoproliferative syndromes) were tested with the same technique. An average decrease of 57% of the GST pi expression was noted in the mononuclear cells of these patients (P < 0.02), with no differences between the untreated and treated cases. The GST alpha and mdr1 mRNA levels did not differ from normal B lymphocytes, but the proportion of patients with no detectable expression of GST mu is lower than in the control (13%). Interestingly, the low content of GST pi in B-CLL could explain the frequent sensitivity of this disease to alkylating agents.

Development of pyrethroid-like fluorescent substrates for glutathione S-transferase

PubMed Central

Huang, Huazhang; Yao, Hongwei; Liu, Jun-Yan; Samra, Aman I.; Kamita, Shizuo G.; Cornel, Anthony J.; Hammock, Bruce D.

2012-01-01

The availability of highly sensitive substrates is critical for the development of precise and rapid assays for detecting changes in glutathione S-transferase (GST) activity that are associated with GST-mediated metabolism of insecticides. In this study, six pyrethroid-like compounds were synthesized and characterized as substrates for insect and mammalian GSTs. All of the substrates were esters composed of the same alcohol moiety, 7-hydroxy-4-methylcoumarin, and acid moieties that structurally mimic some commonly used pyrethroid insecticides including cypermethrin and cyhalothrin. CpGSTD1, a recombinant Delta class GST from the mosquito Culex pipiens, metabolized our pyrethroid-like substrates with both chemical and geometric (i.e., the cis-isomers were metabolized at 2- to 5-fold higher rates than the corresponding trans-isomers) preference. A GST preparation from mouse liver also metabolized most of our pyrethroid-like substrates with both chemical and geometric preference but at 10- to 170-fold lower rates. CpGSTD1 and mouse GSTs metabolized CDNB, a general GST substrate, at more than 200-fold higher rates than our novel pyrethroid-like substrates. There was a 10-fold difference in the specificity constant (kcat/KM ratio) of CpGSTD1 for CDNB and those of CpGSTD1 for cis-DCVC and cis-TFMCVC suggesting that cis-DCVC and cis-TFMCVC may be useful for the detection of GST-based metabolism of pyrethroids in mosquitoes. PMID:23000005

Glutathione S-transferase π complexes with and stimulates Na⁺,K⁺-ATPase.

PubMed

Ochiai, Hideo; Eguchi, Hiroshi; Noguchi, Shunsuke; Hayashi, Yutaro; Nishino, Hideaki; Kawamura, Masaru; Wu, Chau H

2013-01-01

Glutathione S-transferase (GST) was found to complex with the Na⁺,K⁺-ATPase as shown by binding assay using quartz crystal microbalance. The complexation was obstructed by the addition of antiserum to the α-subunit of the Na⁺,K⁺-ATPase, suggesting the specificity of complexation between GST and the Na⁺,K⁺-ATPase. Co-immunoprecipitation experiments, using the anti-α-subunit antiserum to precipitate the GST-Na⁺,K⁺-ATPase complex and then using antibodies specific to an isoform of GST to identify the co-precipitated proteins, revealed that GSTπ was complexed with the Na⁺,K⁺-ATPase. GST stimulated the Na⁺,K⁺-ATPase activity up to 1.4-fold. The level of stimulation exhibited a saturable dose-response relationship with the amount of GST added, although the level of stimulation varied depending on the content of GSTπ in the lots of GST received from supplier. The stimulation was also obtained when recombinant GSTπ was used, confirming the results. When GST was treated with reduced glutathione, GST activity was greatly stimulated, whereas the level of stimulation of the Na⁺,K⁺-ATPase activity was similar to that when untreated GST was added. When GST was treated with H₂O₂, GST activity was greatly diminished while the stimulation of the Na⁺,K⁺-ATPase activity was preserved. The results suggest that GSTπ complexes with the Na⁺,K⁺-ATPase and stimulates the latter independent of its GST activity. Copyright © 2012 John Wiley & Sons, Ltd.

Identification and characterization of the zebrafish glutathione S-transferase Pi-1.

PubMed

Abunnaja, Maryam S; Kurogi, Katsuhisa; Mohammed, Yasir I; Sakakibara, Yoichi; Suiko, Masahito; Hassoun, Ezdihar A; Liu, Ming-Cheh

2017-10-01

Zebrafish has in recent years emerged as a popular vertebrate model for use in pharmacological and toxicological studies. While there have been sporadic studies on the zebrafish glutathione S-transferases (GSTs), the zebrafish GST gene superfamily still awaits to be fully elucidated. We report here the identification of 15 zebrafish cytosolic GST genes in NCBI GenBank database and the expression, purification, and enzymatic characterization of the zebrafish cytosolic GST Pi-1 (GSTP1). The cDNA encoding the zebrafish GSTP1 was cloned from a 3-month-old female zebrafish, expressed in Eschelichia coli host cells, and purified. Purified GSTP1 displayed glutathione-conjugating activity toward 1-chloro-2,4-dinitrobenzene as a representative substrate. The enzymatic characteristics of the zebrafish GSTP1, including pH-dependency, effects of metal cations, and kinetic parameters, were studied. Moreover, the expression of zebrafish GSTP1 at different developmental stages during embryogenesis, throughout larval development, onto maturity was examined. © 2017 Wiley Periodicals, Inc.

Human glutathione transferases catalyzing the bioactivation of anticancer thiopurine prodrugs.

PubMed

Eklund, Birgitta I; Gunnarsdottir, Sjofn; Elfarra, Adnan A; Mannervik, Bengt

2007-06-01

cis-6-(2-Acetylvinylthio)purine (cAVTP) and trans-6-(2-acetylvinylthio)guanine (tAVTG) are thiopurine prodrugs provisionally inactivated by an alpha,beta-unsaturated substituent on the sulfur of the parental thiopurines 6-mercaptopurine (6-MP) and 6-thioguanine (6-TG). The active thiopurines are liberated intracellularly by glutathione (GSH) in reactions catalyzed by glutathione transferases (GSTs) (EC 2.5.1.18). Catalytic activities of 13 human GSTs representing seven distinct classes of soluble GSTs have been determined. The bioactivation of cAVTP and tAVTG occurs via a transient addition of GSH to the activated double bond of the S-substituent of the prodrug, followed by elimination of the thiopurine. The first of these consecutive reactions is rate-limiting for thiopurine release, but GST-activation of this first addition is shifting the rate limitation to the subsequent elimination. Highly active GSTs reveal the transient intermediate, which is detectable by UV spectroscopy and HPLC analysis. LC/MS analysis of the reaction products demonstrates that the primary GSH conjugate, 4-glutathionylbuten-2-one, can react with a second GSH molecule to form the 4-(bis-glutathionyl)butan-2-one. GST M1-1 and GST A4-4 were the most efficient enzymes with tAVTG, and GST M1-1 and GST M2-2 had highest activity with cAVTP. The highly efficient GST M1-1 is polymorphic and is absent in approximately half of the human population. GST P1-1, which is overexpressed in many cancer cells, had no detectable activity with cAVTP and only minor activity with tAVTG. Other GST-activated prodrugs have targeted GST P1-1-expressing cancer cells. Tumors expressing high levels of GST M1-1 or GST A4-4 can be predicted to be particularly vulnerable to chemotherapy with cAVTP or tAVTG.

The effect of glutathione S-transferase M1 and T1 polymorphisms on blood pressure, blood glucose, and lipid profiles following the supplementation of kale (Brassica oleracea acephala) juice in South Korean subclinical hypertensive patients.

PubMed

Han, Jeong-Hwa; Lee, Hye-Jin; Kim, Tae-Seok; Kang, Myung-Hee

2015-02-01

Glutathione S-transferase (GST) forms a multigene family of phase II detoxification enzymes which are involved in the detoxification of reactive oxygen species. This study examines whether daily supplementation of kale juice can modulate blood pressure (BP), levels of lipid profiles, and blood glucose, and whether this modulation could be affected by the GSTM1 and GSTT1 polymorphisms. 84 subclinical hypertensive patients showing systolic BP over 130 mmHg or diastolic BP over 85 mmHg received 300 ml/day of kale juice for 6 weeks, and blood samples were collected on 0-week and 6-week in order to evaluate plasma lipid profiles (total cholesterol, triglyceride, HDL-cholesterol, and LDL-cholesterol) and blood glucose. Systolic and diastolic blood pressure was significantly decreased in all patients regardless of their GSTM1 or GSTT1 polymorphisms after kale juice supplementation. Blood glucose level was decreased only in the GSTM1-present genotype, and plasma lipid profiles showed no difference in both the GSTM1-null and GSTM1-present genotypes. In the case of GSTT1, on the other hand, plasma HDL-C was increased and LDL-C was decreased only in the GSTT1-present type, while blood glucose was decreased only in the GSTT1-null genotype. These findings suggest that the supplementation of kale juice affected blood pressure, lipid profiles, and blood glucose in subclinical hypertensive patients depending on their GST genetic polymorphisms, and the improvement of lipid profiles was mainly greater in the GSTT1-present genotype and the decrease of blood glucose was greater in the GSTM1-present or GSTT1-null genotypes.

The effect of glutathione S-transferase M1 and T1 polymorphisms on blood pressure, blood glucose, and lipid profiles following the supplementation of kale (Brassica oleracea acephala) juice in South Korean subclinical hypertensive patients

PubMed Central

Han, Jeong-Hwa; Lee, Hye-Jin; Kim, Tae-Seok

2015-01-01

BACKGROUND/OBJECTIVES Glutathione S-transferase (GST) forms a multigene family of phase II detoxification enzymes which are involved in the detoxification of reactive oxygen species. This study examines whether daily supplementation of kale juice can modulate blood pressure (BP), levels of lipid profiles, and blood glucose, and whether this modulation could be affected by the GSTM1 and GSTT1 polymorphisms. SUBJECTS/METHODS 84 subclinical hypertensive patients showing systolic BP over 130 mmHg or diastolic BP over 85 mmHg received 300 ml/day of kale juice for 6 weeks, and blood samples were collected on 0-week and 6-week in order to evaluate plasma lipid profiles (total cholesterol, triglyceride, HDL-cholesterol, and LDL-cholesterol) and blood glucose. RESULTS Systolic and diastolic blood pressure was significantly decreased in all patients regardless of their GSTM1 or GSTT1 polymorphisms after kale juice supplementation. Blood glucose level was decreased only in the GSTM1-present genotype, and plasma lipid profiles showed no difference in both the GSTM1-null and GSTM1-present genotypes. In the case of GSTT1, on the other hand, plasma HDL-C was increased and LDL-C was decreased only in the GSTT1-present type, while blood glucose was decreased only in the GSTT1-null genotype. CONCLUSIONS These findings suggest that the supplementation of kale juice affected blood pressure, lipid profiles, and blood glucose in subclinical hypertensive patients depending on their GST genetic polymorphisms, and the improvement of lipid profiles was mainly greater in the GSTT1-present genotype and the decrease of blood glucose was greater in the GSTM1-present or GSTT1-null genotypes. PMID:25671068

Glutathione S-Transferase Protein Expression in Different Life Stages of Zebrafish (Danio rerio)

PubMed Central

Tierbach, Alena; Groh, Ksenia J; Schönenberger, René; Schirmer, Kristin

2018-01-01

Abstract Zebrafish is a widely used animal model in biomedical sciences and toxicology. Although evidence for the presence of phases I and II xenobiotic defense mechanisms in zebrafish exists on the transcriptional and enzyme activity level, little is known about the protein expression of xenobiotic metabolizing enzymes. Given the important role of glutathione S-transferases (GSTs) in phase II biotransformation, we analyzed cytosolic GST proteins in zebrafish early life stages and different organs of adult male and female fish, using a targeted proteomics approach. The established multiple reaction monitoring-based assays enable the measurement of the relative abundance of specific GST isoenzymes and GST classes in zebrafish through a combination of proteotypic peptides and peptides shared within the same class. GSTs of the classes alpha, mu, pi and rho are expressed in zebrafish embryo as early as 4 h postfertilization (hpf). The majority of GST enzymes are present at 72 hpf followed by a continuous increase in expression thereafter. In adult zebrafish, GST expression is organ dependent, with most of the GST classes showing the highest expression in the liver. The expression of a wide range of cytosolic GST isoenzymes and classes in zebrafish early life stages and adulthood supports the use of zebrafish as a model organism in chemical-related investigations. PMID:29361160

Increased resistance to acetaminophen hepatotoxicity in mice lacking glutathione S-transferase Pi

PubMed Central

Henderson, Colin J.; Wolf, C. Roland; Kitteringham, Neil; Powell, Helen; Otto, Diana; Park, B. Kevin

2000-01-01

Overdose of acetaminophen, a widely used analgesic drug, can result in severe hepatotoxicity and is often fatal. This toxic reaction is associated with metabolic activation by the P450 system to form a quinoneimine metabolite, N-acetyl-p-benzoquinoneimine (NAPQI), which covalently binds to proteins and other macromolecules to cause cellular damage. At low doses, NAPQI is efficiently detoxified, principally by conjugation with glutathione, a reaction catalyzed in part by the glutathione S-transferases (GST), such as GST Pi. To assess the role of GST in acetaminophen hepatotoxicity, we examined acetaminophen metabolism and liver damage in mice nulled for GstP (GstP1/P2(−/−)). Contrary to our expectations, instead of being more sensitive, GstP null mice were highly resistant to the hepatotoxic effects of this compound. No significant differences between wild-type (GstP1/P2(+/+)) mice and GstP1/P2(−/−) nulls in either the rate or route of metabolism, particularly to glutathione conjugates, or in the levels of covalent binding of acetaminophen-reactive metabolites to cellular protein were observed. However, although a similar rapid depletion of hepatic reduced glutathione (GSH) was found in both GstP1/P2(+/+) and GstP1/P2(−/−) mice, GSH levels only recovered in the GstP1/P2(−/−) mice. These data demonstrate that GstP does not contribute in vivo to the formation of glutathione conjugates of acetaminophen but plays a novel and unexpected role in the toxicity of this compound. This study identifies new ways in which GST can modulate cellular sensitivity to toxic effects and suggests that the level of GST Pi may be an important and contributing factor in the sensitivity of patients with acetaminophen-induced hepatotoxicity. PMID:11058152

Glutathione S-transferase Pi mediates proliferation of androgen-independent prostate cancer cells

PubMed Central

Hokaiwado, Naomi; Takeshita, Fumitaka; Naiki-Ito, Aya; Asamoto, Makoto; Ochiya, Takahiro; Shirai, Tomoyuki

2008-01-01

Prostate cancers generally acquire an androgen-independent growth capacity with progression, resulting in resistance to antiandrogen therapy. Therefore, identification of the genes regulated through this process may be important for understanding the mechanisms of prostate carcinogenesis. We here utilized androgen-dependent/independent transplantable tumors, newly established with the ‘transgenic rat adenocarcinoma in prostate’ (TRAP) model, to analyze their gene expression using microarrays. Among the overexpressed genes in androgen-independent prostate cancers compared with the androgen-dependent tumors, glutathione S-transferase pi (GST-pi) was included. In line with this, human prostate cancer cell lines PC3 and DU145 (androgen independent) had higher expression of GST-pi compared with LNCaP (androgen dependent) as determined by semiquantitative reverse transcription–polymerase chain reaction analysis. To investigate the roles of GST-pi expression in androgen-independent human prostate cancers, GST-pi was knocked down by a small interfering RNA (siRNA), resulting in significant decrease of the proliferation rate in the androgen-independent PC3 cell line. In vivo, administration of GST-pi siRNA–atelocollagen complex decreased GST-pi protein expression, resulting in enhanced numbers of TdT mediated dUTP-biotin nick-end labering (TUNEL)-positive apoptotic cells. These findings suggest that GST-pi might play important roles in proliferation of androgen-independent human prostate cancer cells. PMID:18413363

Insights into ligand binding to a glutathione S-transferase from mango: Structure, thermodynamics and kinetics

DOE PAGES

Valenzuela-Chavira, Ignacio; Contreras-Vergara, Carmen A.; Arvizu-Flores, Aldo A.; ...

2017-01-17

We studied a mango glutathione S-transferase (GST) ( Mangifera indica) bound to glutathione (GSH) and S-hexyl glutathione (GSX). This GST Tau class (MiGSTU) had a molecular mass of 25.5 kDa. MiGSTU Michaelis-Menten kinetic constants were determined for their substrates obtaining a K m, V max and k cat for CDNB of 0.792 mM, 80.58 mM min -1 and 68.49 s -1 respectively and 0.693 mM, 105.32 mM min -1 and 89.57 s -1, for reduced GSH respectively. MiGSTU had a micromolar affinity towards GSH (5.2 mM) or GSX (7.8 mM). As a result, the crystal structure of the MiGSTU inmore » apo or bound to GSH or GSX generated a model that explains the thermodynamic signatures of binding and showed the importance of enthalpic-entropic compensation in ligand binding to Tau-class GST enzymes.« less

Insights into ligand binding to a glutathione S-transferase from mango: Structure, thermodynamics and kinetics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Valenzuela-Chavira, Ignacio; Contreras-Vergara, Carmen A.; Arvizu-Flores, Aldo A.

We studied a mango glutathione S-transferase (GST) ( Mangifera indica) bound to glutathione (GSH) and S-hexyl glutathione (GSX). This GST Tau class (MiGSTU) had a molecular mass of 25.5 kDa. MiGSTU Michaelis-Menten kinetic constants were determined for their substrates obtaining a K m, V max and k cat for CDNB of 0.792 mM, 80.58 mM min -1 and 68.49 s -1 respectively and 0.693 mM, 105.32 mM min -1 and 89.57 s -1, for reduced GSH respectively. MiGSTU had a micromolar affinity towards GSH (5.2 mM) or GSX (7.8 mM). As a result, the crystal structure of the MiGSTU inmore » apo or bound to GSH or GSX generated a model that explains the thermodynamic signatures of binding and showed the importance of enthalpic-entropic compensation in ligand binding to Tau-class GST enzymes.« less

Characterization of glutathione-S-transferases in zebrafish (Danio rerio).

PubMed

Glisic, Branka; Mihaljevic, Ivan; Popovic, Marta; Zaja, Roko; Loncar, Jovica; Fent, Karl; Kovacevic, Radmila; Smital, Tvrtko

2015-01-01

Glutathione-S-transferases (GSTs) are one of the key enzymes that mediate phase II of cellular detoxification. The aim of our study was a comprehensive characterization of GSTs in zebrafish (Danio rerio) as an important vertebrate model species frequently used in environmental research. A detailed phylogenetic analysis of GST superfamily revealed 27 zebrafish gst genes. Further insights into the orthology relationships between human and zebrafish GSTs/Gsts were obtained by the conserved synteny analysis. Expression of gst genes in six tissues (liver, kidney, gills, intestine, brain and gonads) of adult male and female zebrafish was determined using qRT-PCR. Functional characterization was performed on 9 cytosolic Gst enzymes after overexpression in E. coli and subsequent protein purification. Enzyme kinetics was measured for GSH and a series of model substrates. Our data revealed ubiquitously high expression of gstp, gstm (except in liver), gstr1, mgst3a and mgst3b, high expression of gsto2 in gills and ovaries, gsta in intestine and testes, gstt1a in liver, and gstz1 in liver, kidney and brain. All zebrafish Gsts catalyzed the conjugation of GSH to model GST substrates 1-chloro-2,4-dinitrobenzene (CDNB) and monochlorobimane (MCB), apart from Gsto2 and Gstz1 that catalyzed GSH conjugation to dehydroascorbate (DHA) and dichloroacetic acid (DCA), respectively. Affinity toward CDNB varied from 0.28 mM (Gstp2) to 3.69 mM (Gstm3), while affinity toward MCB was in the range of 5 μM (Gstt1a) to 250 μM (Gstp1). Affinity toward GSH varied from 0.27 mM (Gstz1) to 4.45 mM (Gstt1a). Turnover number for CDNB varied from 5.25s(-1) (Gstt1a) to 112s(-1) (Gstp2). Only Gst Pi enzymes utilized ethacrynic acid (ETA). We suggest that Gstp1, Gstp2, Gstt1a, Gstz1, Gstr1, Mgst3a and Mgst3b have important role in the biotransformation of xenobiotics, while Gst Alpha, Mu, Pi, Zeta and Rho classes are involved in the crucial physiological processes. In summary, this study provides the

The Relationship Between Glutathione S-Transferase-P1 and Beta-2 Adrenoreceptor Genotypes with Asthmatic Patients in the Turkish Population.

PubMed

Kaymak, Cetin; Aygun Kocabas, Neslihan; Aydın, Nesrin; Oztuna, Derya; Karakaya, Ali Esat

2016-09-01

Individual differences in the activity of enzymes that metabolize xenobiotics can impact health and disease. Beta-2 adrenoreceptor (ADRB2) is a functional G-coupled protein expressed in the vascular endothelium of lungs, alveolar walls, and the ganglions of cholinergic nerves which induces bronchodilation in response to catecholamines. Glutathione S-Transferase-P1 (GSTP1) is a candidate pi class GST gene, which controls pi class glutathione S-transferase activity. In this study we determined the relationship between the ADRB2 Arg16Gly polymorphism and GSTP1 polymorphisms, involved in bronchodilator response and oxidative stress, respectively, with susceptibility to asthma. In this study, 129 asthmatic patients and 127 healthy control cases were recruited to determine ADRB2 and GSTP1 genotypes by allele-specific polymerase chain reaction and restriction fragment length polymorphism assays, respectively. The ADRB2 genotype frequencies of the patients and control cases were found to be 10.9% (Arg16Arg), 48.8% (Arg16Gly), and 40.3% (Gly16Gly) and 24.4% (Arg16Arg), 36.2% (Arg16Gly), and 39.4% (Gly16Gly), respectively. GSTP1 genotype frequencies of patients and control cases were found to be 55% (Ile105Ile), 43.4% (Ile105Val), and 1.6% (Val105Val) and 75.6% (Ile105Ile), 22% (Ile105Val), and 2.4% (Val105Val), respectively. In the case of the GSTP1 gene, we found statistically significant differences in the genotype frequency of Ile105Val and the allele frequency of Val105 in the asthmatic group compared with the controls. Moreover, we observed a relationship between allele frequencies and clinical phenotypes including atopia nocturnal dyspnea, and steroid dependency in the asthmatic patients. Our results suggest that the GSTP1 Ile105Val polymorphism may be linked to the severeness of airway dysfunction.

Functional interaction of glutathione S-transferase pi and peroxiredoxin 6 in intact cells.

PubMed

Zhou, Suiping; Lien, Yu-Chin; Shuvaeva, Tea; DeBolt, Kristine; Feinstein, Sheldon I; Fisher, Aron B

2013-02-01

Peroxiredoxin 6 (Prdx6) is a 1-Cys member of the peroxiredoxin superfamily that plays an important role in antioxidant defense. Glutathionylation of recombinant Prdx6 mediated by π glutathione S-transferase (GST) is required for reduction of the oxidized Cys and completion of the peroxidatic catalytic cycle in vitro. This study investigated the requirement for πGST in intact cells. Transfection with a plasmid construct expressing πGST into MCF7, a cell line that lacks endogenous πGST, significantly increased phospholipid peroxidase activity as measured in cell lysates and protected intact cells against a peroxidative stress. siRNA knockdown indicated that this increased peroxidase activity was Prdx6 dependent. Interaction between πGST and Prdx6, evaluated by the Duolink Proximity Ligation Assay, was minimal under basal conditions but increased dramatically following treatment of cells with the oxidant, tert-butyl hydroperoxide. Interaction was abolished by mutation of C47, the active site for Prdx6 peroxidase activity. Depletion of cellular GSH by treatment of cells with buthionine sulfoximine had no effect on the interaction of Prdx6 and πGST. These data are consistent with the hypothesis that oxidation of the catalytic cysteine in Prdx6 is required for its interaction with πGST and that the interaction plays an important role in regenerating the peroxidase activity of Prdx6. Copyright © 2012 Elsevier Ltd. All rights reserved.

Biochemical effects of glyphosate based herbicide, Excel Mera 71 on enzyme activities of acetylcholinesterase (AChE), lipid peroxidation (LPO), catalase (CAT), glutathione-S-transferase (GST) and protein content on teleostean fishes.

PubMed

Samanta, Palas; Pal, Sandipan; Mukherjee, Aloke Kumar; Ghosh, Apurba Ratan

2014-09-01

Effects of glyphosate based herbicide, Excel Mera 71 at a dose of 17.20mg/l on enzyme activities of acetylcholinesterase (AChE), lipid peroxidation (LPO), catalase (CAT), glutathione-S-transferase (GST) and protein content were measured in different tissues of two Indian air-breathing teleosts, Anabas testudineus (Bloch) and Heteropneustes fossilis (Bloch) during an exposure period of 30 days under laboratory condition. AChE activity was significantly increased in all the investigated tissues of both fish species and maximum elevation was observed in brain of H. fossilis, while spinal cord of A. testudineus showed minimum increment. Fishes showed significant increase LPO levels in all the tissues; highest was observed in gill of A. testudineus but lowest LPO level was observed in muscle of H. fossilis. CAT was also enhanced in both the fishes, while GST activity in liver diminished substantially and minimum was observed in liver of A. testudineus. Total protein content showed decreased value in all the tissues, maximum reduction was observed in liver and minimum in brain of A. testudineus and H. fossilis respectively. The results indicated that Excel Mera 71 caused serious alterations in the enzyme activities resulting into severe deterioration of fish health; so, AChE, LPO, CAT and GST can be used as suitable indicators of herbicidal toxicity. Copyright © 2014 Elsevier Inc. All rights reserved.

Occupational exposure to antineoplastic agents induces a high level of chromosome damage. Lack of an effect of GST polymorphisms

DOE Office of Scientific and Technical Information (OSTI.GOV)

Testa, Antonella; Giachelia, Manuela; Palma, Selena

The aim of our study was to investigate whether occupational exposure to antineoplastic drugs (AND) resulted in genetic damage, possibly indicative of adverse health effects in the long term. We performed a chromosomal aberrations (CA) analysis in peripheral blood lymphocytes (PBL) of a group of 76 trained nurses occupationally exposed to AND. Furthermore, we analysed whether genetic polymorphisms in four metabolic genes of the glutathione S-transferase (GST) family involved in antineoplastic drugs detoxification (GSTM1, GSTT1, GSTP1, GSTA1) had any effect on the yield of chromosomal aberrations in nurses exposed to antineoplastic agents. The exposed group showed a very significant increasemore » of genetic damage (p < 0.0001) potentially indicative of an increased risk of cancer. Unexpectedly, besides the elevated level of chromatid-type aberrations usually related to exposure to chemical agents, we found also severe chromosome damages such as chromosome deletions and dicentric chromosomes, usually related to radiation exposure. No significant association was detected between all GSTs genotypes and chromosome damage. In conclusion, our data show how the occupational exposure to AND is associated to a potential cancer risk, suggesting that current prevention methods do not completely eliminate opportunities for exposure and supporting the need to improve the actual safety practices.« less

Lack of association between the glutathione-s-transferase genes (GSTT1 and GSTM1) and nasal polyposis.

PubMed

Arbag, Hamdi; Cora, Tulin; Acar, Hasan; Ozturk, Kayhan; Sari, Fatih; Ulusoy, Bulent

2006-03-01

To evaluate the glutation-S-transferase (GST) polymorphisms (GSTM1 and GSTT1) in nasal polyposis (NP). The study population consisted of 102 unrelated healthy individuals and 98 patients with NP (67 without asthma, 31 with asthma). Genotyping of the polymorphism in the GSTM1 and GSTT1 genes was performed using the multiplex polymerase chain reaction (PCR)-based method. GSTM1 and GSTT1 null-genotypes were found in 46.1% and 23.5% of the controls, and in 43.9% and 33.7% of the NP patients, respectively. These differences were not significant (for GSTM1 null odds ratio (OR) = 0.92; 95% confidence interval (CI) = 0.52-1.6 and for GSTT1, OR = 1.65; 95% CI = 0.89-3.07). Although no significant difference for combined GSTM1 and GSTT1 null genotypes between control (8.8%) and NP patients (17.3%) was found, there was a 2.16-fold increased proportion in the NP with the combined GSTM1-null and GSTT1-null genotype (OR = 2.16; 95% CI = 0.91-5.13). These results suggest that there is lack of association between GSTM1 and GSTT1 polymorphisms and NP. The GSTM1 or GSTT1 polymorphisms had also no relevant developing effect on NP patients without or with asthma.

Insights into ligand binding to a Glutathione S-transferase from mango: structure, thermodynamics and kinetics

PubMed Central

Valenzuela-Chavira, Ignacio; Contreras-Vergara, Carmen A.; Arvizu-Flores, Aldo A.; Serrano-Posada, Hugo; Lopez-Zavala, Alonso A.; García-Orozco, Karina D.; Hernandez-Paredes, Javier; Rudiño-Piñera, Enrique; Stojanoff, Vivian; Sotelo-Mundo, Rogerio R.; Islas-Osuna, Maria A.

2017-01-01

We studied a mango glutathione S-transferase (GST) (Mangifera indica) bound to glutathione (GSH) and S-hexyl glutathione (GSX). This GST Tau class (MiGSTU) had a molecular mass of 25.5 kDa. MiGSTU Michaelis-Menten kinetic constants were determined for their substrates obtaining a Km, Vmax and kcat for CDNB of 0.792 mM, 80.58 mM·min−1 and 68.49 s−1 respectively and 0.693 mM, 105.32 mM·min−1 and 89.57 s−1, for reduced GSH respectively. MiGSTU had a micromolar affinity towards GSH (5.2 μM) or GSX (7.8 μM). The crystal structure of the MiGSTU in apo or bound to GSH or GSX generated a model that explains the thermodynamic signatures of binding and showed the importance of enthalpic-entropic compensation in ligand binding to Tau-class GST enzymes. PMID:28104507

Transfected Babesia bovis Expressing a Tick GST as a Live Vector Vaccine

PubMed Central

Oldiges, Daiane P.; Laughery, Jacob M.; Tagliari, Nelson Junior; Leite Filho, Ronaldo Viana; Davis, William C.; da Silva Vaz, Itabajara; Termignoni, Carlos; Knowles, Donald P.; Suarez, Carlos E.

2016-01-01

The Rhipicephalus microplus tick is a notorious blood-feeding ectoparasite of livestock, especially cattle, responsible for massive losses in animal production. It is the main vector for transmission of pathogenic bacteria and parasites, including Babesia bovis, an intraerythrocytic apicomplexan protozoan parasite responsible for bovine Babesiosis. This study describes the development and testing of a live B. bovis vaccine expressing the protective tick antigen glutathione-S-transferase from Haemaphysalis longicornis (HlGST). The B. bovis S74-T3B parasites were electroporated with a plasmid containing the bidirectional Ef-1α (elongation factor 1 alpha) promoter of B. bovis controlling expression of two independent genes, the selectable marker GFP-BSD (green fluorescent protein–blasticidin deaminase), and HlGST fused to the MSA-1 (merozoite surface antigen 1) signal peptide from B. bovis. Electroporation followed by blasticidin selection resulted in the emergence of a mixed B. bovis transfected line (termed HlGST) in in vitro cultures, containing parasites with distinct patterns of insertion of both exogenous genes, either in or outside the Ef-1α locus. A B. bovis clonal line termed HlGST-Cln expressing intracellular GFP and HlGST in the surface of merozoites was then derived from the mixed parasite line HlGST using a fluorescent activated cell sorter. Two independent calf immunization trials were performed via intravenous inoculation of the HlGST-Cln and a previously described control consisting of an irrelevant transfected clonal line of B. bovis designated GFP-Cln. The control GFP-Cln line contains a copy of the GFP-BSD gene inserted into the Ef-1α locus of B. bovis in an identical fashion as the HIGST-Cln parasites. All animals inoculated with the HlGST-Cln and GFP-Cln transfected parasites developed mild babesiosis. Tick egg fertility and fully engorged female tick weight was reduced significantly in R. microplus feeding on HlGST-Cln-immunized calves

Glutathione S-transferase Pi expression in invasive breast cancer and its relation with the clinical outcome.

PubMed

Franco, R L; Schenka, N G M; Schenka, A A A; Rezende, L F; Gurgel, M S C

2012-01-01

Glutathione S-transferase (GST) is a cytosolic enzymatic system involved in cellular detoxifying process. In vitro studies have shown that the presence of this enzymatic system in breast carcinoma cells can accelerate the elimination of drugs commonly used in chemotherapy, thereby decreasing its efficacy. The aim of the present study was to evaluate the association between GST Pi expression by breast carcinoma cells and disease-free and overall survival. Ninety-five female patients with invasive breast carcinoma submitted to surgical treatment and adjuvant chemotherapy from January, 1995 to June, 1997 and followed until August, 2006 were evaluated. The expression of GST Pi in breast carcinoma cells, determined by immunohistochemistry, was correlated with several clinical and pathological parameters of prognostic significance. There were 36 (37.9%) GST Pi-positive cases. GST Pi immunoexpression was not significantly correlated with patient's age, histological tumor type, clinical stage, hormone receptor status and survival. On the other hand, GST Pi positivity showed a significant correlation with a lower histological grade/C-erb-B2 negative breast carcinoma phenotype. The findings suggest that GST Pi expression does not constitute a satisfactory prognostic factor in breast cancer.

Variable Levels of Glutathione S-Transferases Are Responsible for the Differential Tolerance to Metolachlor between Maize (Zea mays) Shoots and Roots.

PubMed

Li, Dongzhi; Xu, Li; Pang, Sen; Liu, Zhiqian; Wang, Kai; Wang, Chengju

2017-01-11

Glutathione S-transferases (GSTs) play important roles in herbicide tolerance. However, studies on GST function in herbicide tolerance among plant tissues are still lacking. To explore the mechanism of metolachlor tolerance difference between maize shoots and roots, the effects of metolachlor on growth, GST activity, and the expression of the entire GST gene family were investigated. It was found that this differential tolerance to metolachlor was correlated with contrasting GST activity between the two tissues and can be eliminated by a GST inhibitor. An in vitro metolachlor-glutathione conjugation assay confirmed that the transformation of metolachlor is 2-fold faster in roots than in shoots. The expression analysis of the GST gene family revealed that most GST genes are expressed much higher in roots than shoots, both in control and in metolachlor-treated plants. Taken together, higher level expression of most GST genes, leading to higher GST activity and faster herbicide transformation, appears to be responsible for the higher tolerance to metolachlor of maize roots than shoots.

Detection of Glutathione by Glutathione-S-Transferase-Nanoconjugate Ensemble Electrochemical Device.

PubMed

Barman, Ujjwol; Mukhopadhyay, Gargi; Goswami, Namami; Ghosh, Siddhartha Sankar; Paily, Roy P

2017-06-01

This paper reports a novel electrochemical method for detection of Glutathione (GSH) using Glutathione-S-Transferase (GST) - ZnO composite nanoparticles to investigate the prospects of the method for detection of cancer at an early stage. The purified GST enzyme was bound with ZnO nanoparticles by electrostatic interactions and the nanocomposite was dropcast on a silicon dioxide wafer. The GST functionalized deposited layer was then used as a chemiresistive channel to detect conjugation reaction between GSH and 1-Chloro-2, 4-Dinitrobenzene (CDNB). The zeta potential values of the ZnO nanoparticles and the GST were found to be 13.4 mV and-6.21 mV, respectively. Around 73.8% binding was observed between the enzyme and ZnO nanoparticles. I - V analysis of the chemiresistive channel showed an increase in conductivity of the channel due to conjugation reaction between GSH and CDNB as compared with that of GSH or CDNB alone. I - V characterization of the GST functionalized layer was performed at various concentrations of GSH and a sensitivity and limit of detection of 5.68 nA/ [Formula: see text] and 41.9 nM were obtained, respectively. Thus from I - V analysis of the chemiresistivechannel, the detectionand quantification of GSH could be obtained. The kinetic parameters of both GST and nanoconjugate of ZnO nanoparticles andGSTwere determinedwith respect to its substrates, GSH and CDNB, using Michaelis-Mentenmodel. This novel approach of detection of GSH bymeans of ZnO nanoparticle and GST enzyme composite can be further analyzed for in vitro experiments, which will lead us to a new and efficient way of detecting certain types of cancers at an early stage.

A SERS protocol as a potential tool to access 6-mercaptopurine release accelerated by glutathione-S-transferase.

PubMed

Wang, Ying; Sun, Jie; Yang, Qingran; Lu, Wenbo; Li, Yan; Dong, Jian; Qian, Weiping

2015-11-21

The developed method for monitoring GST, an important drug metabolic enzyme, could greatly facilitate researches on relative biological fields. In this work, we have developed a SERS technique to monitor the absorbance behaviour of 6-mercaptopurine (6-MP) and its glutathione-S-transferase (GST)-accelerated glutathione (GSH)-triggered release behaviour on the surface of gold nanoflowers (GNFs), using the GNFs as excellent SERS substrates. The SERS signal was used as an indicator of absorbance or release of 6-MP on the gold surface. We found that GST can accelerate GSH-triggered release behaviour of 6-MP from the gold surface. We speculated that GST catalyzes nucleophilic GSH to competitively bind with the electrophilic substance 6-MP. Experimental results have proved that the presented SERS protocol can be utilized as an effective tool for accessing the release of anticancer drugs.

Urinary polycyclic aromatic hydrocarbon (OH-PAH) metabolite concentrations and the effect of GST polymorphisms among US Air Force personnel exposed to jet fuel.

PubMed

Rodrigues, Ema G; Smith, Kristen; Maule, Alexis L; Sjodin, Andreas; Li, Zheng; Romanoff, Lovisa; Kelsey, Karl; Proctor, Susan; McClean, Michael D

2014-05-01

To evaluate the association between inhalation exposure to jet propulsion fuel 8 (JP-8) and urinary metabolites among US Air Force (USAF) personnel, and investigate the role of glutathione S-transferase polymorphisms. Personal air samples were collected from 37 full-time USAF personnel during 4 consecutive workdays and analyzed for JP-8 constituents and total hydrocarbons. Pre- and postshift urine samples were collected each day and analyzed for polycyclic aromatic hydrocarbon urinary metabolites. Work shift exposure to total hydrocarbons was significantly associated with postshift urinary 1-naphthol (β = 0.17; P = <0.0001), 2-naphthol (β = 0.09; P = 0.005), and 2-hydroxyfluorene concentrations (β = 0.08; P = 0.006), and a significant gene-environment interaction was observed with glutathione S-transferase mu-1. USAF personnel experience inhalation exposure to JP-8, which is associated with absorption of JP-8 constituents while performing typical job-related tasks, and in our data the glutathione S-transferase mu-1 polymorphism was associated with differential metabolism of naphthalene.

Chlortetracycline detoxification in maize via induction of glutathione S-transferases after antibiotic exposure.

PubMed

Farkas, Michael H; Berry, James O; Aga, Diana S

2007-02-15

Soil contamination with nonmetabolized antibiotics is an emerging environmental concern, especially on agricultural croplands that receive animal manure as fertilizer. In this study, phytotoxicity of chlortetracycline (CTC) antibiotics on pinto beans (Phaseolus vulgaris) and maize (Zea mays) was investigated under controlled conditions. When grown in CTC-treated soil, a significant increase in the activities of the plant stress proteins glutathione S-transferases (GST) and peroxidases (POX) were observed in maize plants, but not in pinto beans. In vitro conjugation reactions demonstrated that the induced GST in maize catalyzed the conjugation of glutathione (GSH) with CTC, producing stable conjugates that were structurally characterized using liquid chromatography/mass spectrometry. The antibiotic-induced GST produced CTC-glutathione conjugate at relative concentrations 2-fold higher than that produced by constitutively expressed GST extracted from untreated maize. On the other hand, GST extracted from pinto beans (both treated and untreated) did not efficiently catalyze glutathione conjugation with CTC. These results suggest that maize is able to detoxify chlortetracycline via the glutathione pathway, whereas pinto beans cannot. This may explain the observed stunted growth of pinto beans after antibiotic treatment. This study demonstrates the importance of plant uptake in determining the fate of antibiotics in soil and their potential phytotoxicity to susceptible plants.

Construction of fusion vectors of corynebacteria: expression of glutathione-S-transferase fusion protein in Corynebacterium acetoacidophilum ATCC 21476.

PubMed

Srivastava, Preeti; Deb, J K

2002-07-02

A series of fusion vectors containing glutathione-S-transferase (GST) were constructed by inserting GST fusion cassette of Escherichia coli vectors pGEX4T-1, -2 and -3 in corynebacterial vector pBK2. Efficient expression of GST driven by inducible tac promoter of E. coli was observed in Corynebacterium acetoacidophilum. Fusion of enhanced green fluorescent protein (EGFP) and streptokinase genes in this vector resulted in the synthesis of both the fusion proteins. The ability of this recombinant organism to produce several-fold more of the product in the extracellular medium than in the intracellular space would make this system quite attractive as far as the downstream processing of the product is concerned.

Oxidative stress markers and genetic polymorphisms of glutathione S-transferase T1, M1, and P1 in a subset of children with autism spectrum disorder in Lagos, Nigeria.

PubMed

Oshodi, Y; Ojewunmi, O; Oshodi, T A; Ijarogbe, G T; Ogun, O C; Aina, O F; Lesi, Fea

2017-09-01

The role of oxidative stress has been identified in the development of autism spectrum disorder (ASD), and polymorphisms of glutathione S-transferase have been associated with some diseases linked to oxidative stress. Hence, we evaluated the serum levels of oxidative stress markers and investigated genetic polymorphisms of glutathione S-transferase associated with autism. Forty-two children clinically diagnosed with ASD using the Diagnostic and Statistical Manual for Mental Disorders (DSM-5) criteria and a clinical interview were included in the study. Twenty-three age-matched controls without any known genetic/developmental disorder were also recruited. Oxidative stress markers along with the genetic polymorphisms of glutathione S-transferase were determined. Reduced glutathione in ASD patients was significantly lower than the control (P = 0.008), whereas other oxidative stress markers measured were not significantly different in both the control and case populations. The frequencies of GSTT1 and GSTM1 null genotypes were lower among the controls compared with the cases, however, no association risk was observed. The observed risk of carrying Val/Val genotype among the cases was approximately six times that of the controls. Individuals with ASD showed a significant diminished level of reduced glutathione, however, the distribution of GSTT1, GSTM1, and GSTP1 polymorphisms was not found to be associated with autism in this study population.

Glutathione S-transferase iso-enzymes in perfusate from pumped kidneys are associated with delayed graft function

PubMed Central

Hall, Isaac E.; Bhangoo, Ronik S.; Reese, Peter P.; Doshi, Mona D.; Weng, Francis L.; Hong, Kwangik; Lin, Haiqun; Han, Gang; Hasz, Rick D.; Goldstein, Michael J.; Schröppel, Bernd; Parikh, Chirag R.

2014-01-01

Accurate and reliable assessment tools are needed in transplantation. The objective of this prospective, multicenter study was to determine the associations of the alpha and pi iso-enzymes of glutathione S-transferase (GST), measured from perfusate solution at the start and end (base and post) of kidney allograft machine perfusion, with subsequent delayed graft function (DGF). We also compared GST iso-enzyme perfusate levels from discarded versus transplanted kidneys. A total of 428 kidneys were linked to outcomes as recorded by the United Network of Organ Sharing. DGF, defined as any dialysis in the first week of transplant, occurred in 141 recipients (32%). Alpha and pi-GST levels significantly increased during machine perfusion. The adjusted relative risks (95% confidence interval) of DGF with each log-unit increase in base and post pi-GST were 1.14 (1.0-1.28) and 1.33 (1.02-1.72), respectively. Alpha-GST was not independently associated with DGF. There were no significant differences in GST values between discarded and transplanted kidneys, though renal resistance was significantly higher in discarded kidneys. We found pi-GST at the end of machine perfusion to be independently associated with DGF. Further studies should elucidate the utility of GST for identifying injured kidneys with regard to organ allocation, discard and recipient management decisions. PMID:24612768

Glutathione S-transferase M1 and glutathione S-transferase T1 genotype in chronic pancreatitis: a meta-analysis.

PubMed

Zhong, Yanjun; Zou, Runmei; Cao, Jie; Peng, Mou

2015-02-01

A meta-analysis to determine the association between chronic pancreatitis and glutathione-S transferase (GST) mu 1 (GSTM1) and theta 1 (GSTT1) deletions. Case-control studies concerning the relationship between chronic pancreatitis and GSTM1 or GSTT1 deletions were identified (up to October 2013). Meta-analyses of the association between GSTM1 and GSTT1 genotype and chronic pancreatitis or alcoholic chronic pancreatitis (ACP) were performed. Seven studies were included in the meta-analysis (650 patients/1382 controls for GSTM1 and 536 patients/1304 controls for GSTT1). There were no significant relationships between GSTM1/GSTT1 and chronic pancreatitis or GSTT1 and ACP. There was a significant association between GSTM1 null genotype and ACP (odds ratio 1.16, 95% confidence intervals 1.03, 1.30). The GSTM1 null genotype was significantly associated with ACP risk. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

Cloning, expression and biochemical characterization of one Epsilon-class (GST-3) and ten Delta-class (GST-1) glutathione S-transferases from Drosophila melanogaster, and identification of additional nine members of the Epsilon class.

PubMed Central

Sawicki, Rafał; Singh, Sharda P; Mondal, Ashis K; Benes, Helen; Zimniak, Piotr

2003-01-01

From the fruitfly, Drosophila melanogaster, ten members of the cluster of Delta-class glutathione S-transferases (GSTs; formerly denoted as Class I GSTs) and one member of the Epsilon-class cluster (formerly GST-3) have been cloned, expressed in Escherichia coli, and their catalytic properties have been determined. In addition, nine more members of the Epsilon cluster have been identified through bioinformatic analysis but not further characterized. Of the 11 expressed enzymes, seven accepted the lipid peroxidation product 4-hydroxynonenal as substrate, and nine were active in glutathione conjugation of 1-chloro-2,4-dinitrobenzene. Since the enzymically active proteins included the gene products of DmGSTD3 and DmGSTD7 which were previously deemed to be pseudogenes, we investigated them further and determined that both genes are transcribed in Drosophila. Thus our present results indicate that DmGSTD3 and DmGSTD7 are probably functional genes. The existence and multiplicity of insect GSTs capable of conjugating 4-hydroxynonenal, in some cases with catalytic efficiencies approaching those of mammalian GSTs highly specialized for this function, indicates that metabolism of products of lipid peroxidation is a highly conserved biochemical pathway with probable detoxification as well as regulatory functions. PMID:12443531

Nuclear translocation of glutathione S-transferase {pi} is mediated by a non-classical localization signal

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kawakatsu, Miho; Goto, Shinji, E-mail: sgoto@nagasaki-u.ac.jp; Yoshida, Takako

2011-08-12

Highlights: {yields} Nuclear translocation of GST{pi} is abrogated by the deletion of the last 16 amino acid residues in the carboxy-terminal region, indicating that residues 195-208 of GST{pi} are required for nuclear translocation. {yields} The lack of a contiguous stretch of positively charged amino acid residues within the carboxy-terminal region of GST{pi}, suggests that the nuclear translocation of GST{pi} is mediated by a non-classical nuclear localization signal. {yields} An in vitro transport assay shows that the nuclear translocation of GST{pi} is dependent on cytosolic factors and ATP. -- Abstract: Glutathione S-transferase {pi} (GST{pi}), a member of the GST family ofmore » multifunctional enzymes, is highly expressed in human placenta and involved in the protection of cellular components against electrophilic compounds or oxidative stress. We have recently found that GST{pi} is expressed in the cytoplasm, mitochondria, and nucleus in some cancer cells, and that the nuclear expression of GST{pi} appears to correlate with resistance to anti-cancer drugs. Although the mitochondrial targeting signal of GST{pi} was previously identified in the amino-terminal region, the mechanism of nuclear translocation remains completely unknown. In this study, we find that the region of GST{pi}195-208 is critical for nuclear translocation, which is mediated by a novel and non-classical nuclear localization signal. In addition, using an in vitro transport assay, we demonstrate that the nuclear translocation of GST{pi} depends on the cytosolic extract and ATP. Although further experiments are needed to understand in depth the precise mechanism of nuclear translocation of GST{pi}, our results may help to establish more efficient anti-cancer therapy, especially with respect to resistance to anti-cancer drugs.« less

Urinary Polycyclic Aromatic Hydrocarbon (OH-PAH) Metabolite Concentrations and the Effect of GST Polymorphisms Among US Air Force Personnel Exposed to Jet Fuel

PubMed Central

Rodrigues, Ema G.; Smith, Kristen; Maule, Alexis L.; Sjodin, Andreas; Li, Zheng; Romanoff, Lovisa; Kelsey, Karl; Proctor, Susan; McClean, Michael D.

2016-01-01

Objective To evaluate the association between inhalation exposure to jet propulsion fuel 8 (JP-8) and urinary metabolites among US Air Force (USAF) personnel, and investigate the role of glutathione S-transferase polymorphisms. Methods Personal air samples were collected from 37 full-time USAF personnel during 4 consecutive workdays and analyzed for JP-8 constituents and total hydrocarbons. Pre- and postshift urine samples were collected each day and analyzed for polycyclic aromatic hydrocarbon urinary metabolites. Results Work shift exposure to total hydrocarbons was significantly associated with postshift urinary 1-naphthol (β = 0.17; P = <0.0001), 2-naphthol (β = 0.09; P = 0.005), and 2-hydroxyfluorene concentrations (β = 0.08; P = 0.006), and a significant gene-environment interaction was observed with glutathione S-transferase mu-1. Conclusions USAF personnel experience inhalation exposure to JP-8, which is associated with absorption of JP-8 constituents while performing typical job-related tasks, and in our data the glutathione S-transferase mu-1 polymorphism was associated with differential metabolism of naphthalene. PMID:24806557

The fungal glutathione S-transferase system. Evidence of new classes in the wood-degrading basidiomycete Phanerochaete chrysosporium.

PubMed

Morel, Mélanie; Ngadin, Andrew A; Droux, Michel; Jacquot, Jean-Pierre; Gelhaye, Eric

2009-12-01

The recent release of several basidiomycete genome sequences allows an improvement of the classification of fungal glutathione S-transferases (GSTs). GSTs are well-known detoxification enzymes which can catalyze the conjugation of glutathione to non-polar compounds that contain an electrophilic carbon, nitrogen, or sulfur atom. Following this mechanism, they are able to metabolize drugs, pesticides, and many other xenobiotics and peroxides. A genomic and phylogenetic analysis of GST classes in various sequenced fungi--zygomycetes, ascomycetes, and basidiomycetes--revealed some particularities in GST distribution, in comparison with previous analyses with ascomycetes only. By focusing essentially on the wood-degrading basidiomycete Phanerochaete chrysosporium, this analysis highlighted a new fungal GST class named GTE, which is related to bacterial etherases, and two new subclasses of the omega class GSTs. Moreover, our phylogenetic analysis suggests a relationship between the saprophytic behavior of some fungi and the number and distribution of some GST isoforms within specific classes.

Characterisation of Dermanyssus gallinae glutathione S-transferases and their potential as acaricide detoxification proteins.

PubMed

Bartley, Kathryn; Wright, Harry W; Bull, Robert S; Huntley, John F; Nisbet, Alasdair J

2015-06-26

Glutathione S-transferases (GSTs) facilitate detoxification of drugs by catalysing the conjugation of the reduced glutathione (GSH) to electrophilic xenobiotic substrates and therefore have a function in multi-drug resistance. As a result, knowledge of GSTs can inform both drug resistance in, and novel interventions for, the control of endo- and ectoparasite species. Acaricide resistance and the need for novel control methods are both pressing needs for Dermanyssus gallinae, a highly economically important haematophagous ectoparasite of poultry. A transcriptomic database representing D. gallinae was examined and 11 contig sequences were identified with GST BlastX identities. The transcripts represented by 3 contigs, designated Deg-GST-1, -2 and -3, were fully sequenced and further characterized by phylogenetic analysis. Recombinant versions of Deg-GST-1, -2 and -3 (rDeg-GST) were enzymically active and acaricide-binding properties of the rDeg-GSTs were established by evaluating the ability of selected acaricides to inhibit the enzymatic activity of rDeg-GSTs. 6 of the identified GSTs belonged to the mu class, followed by 3 kappa, 1 omega and 1 delta class molecules. Deg-GST-1 and -3 clearly partitioned with orthologous mu class GSTs and Deg-GST-2 partitioned with delta class GSTs. Phoxim, permethrin and abamectin significantly inhibited rDeg-GST-1 activity by 56, 35 and 17% respectively. Phoxim also inhibited rDeg-2-GST (14.8%) and rDeg-GST-3 (20.6%) activities. Deg-GSTs may have important roles in the detoxification of pesticides and, with the increased occurrence of acaricide resistance in this species worldwide, Deg-GSTs are attractive targets for novel interventions.

Glutathione-S-transferase-oxidative stress relationship in the internal spermatic vein blood of infertile men with varicocele.

PubMed

Mostafa, T; Rashed, L A; Zeidan, A S; Hosni, A

2015-02-01

This study aimed to assess glutathione-S-transferase (GST) enzyme- oxidative stress (OS) relationship in the internal spermatic vein (ISV) of infertile men associated with varicocele (Vx). Ninety five infertile oligoasthenoteratozoospemic (OAT) men associated with Vx were subjected to history taking, clinical examination and semen analysis. During inguinal varicocelectomy, GST, malondialdehyde (MDA) and glutathione peroxidase (GPx) were estimated in the blood samples drawn from ISV and median cubital veins. The mean levels of GST, GPx were significantly decreased and the mean level of GPx was significantly increased in the ISV compared with the peripheral blood. The mean level of GST and GPx in the ISV was significantly decreased, and the mean level of MDA was significantly increased in Vx grade III compared with Vx grade II cases. There was nonsignificant difference in the mean level of GST in the ISV in unilateral Vx cases compared with bilateral Vx cases. There was significant positive correlation of GST with sperm count, sperm motility, GPx and significant negative correlation with sperm abnormal forms, MDA. It is concluded that ISV of infertile men associated with Vx has decreased levels of GST compared with peripheral venous circulation that is correlated with both OS and Vx grade. © 2014 Blackwell Verlag GmbH.

Thermal- and urea-induced unfolding processes of glutathione S-transferase by molecular dynamics simulation.

PubMed

Li, Jiahuang; Chen, Yuan; Yang, Jie; Hua, Zichun

2015-05-01

The Schistosoma juponicum 26 kDa glutathione S-transferase (sj26GST) consists of the N-terminal domain (N-domain), containing three alpha-helices (named H1-H3) and four anti-parallel beta-strands (S1-S4), and the C-terminal domain (C-domain), comprising five alpha-helices (named H4-H8). In present work, molecular dynamics simulations and fluorescence spectroscopic were used to gain insights into the unfolding process of sj26GST. The molecular dynamics simulations on sj26GST subunit both in water and in 8 M urea were carried out at 300 K, 400 K and 500 K, respectively. Spectroscopic measurements were employed to monitor structural changes. Molecular dynamics simulations of sj26GST subunit induced by urea and temperature showed that the initial unfolding step of sj26GST both in water and urea occurred on N-domain, involving the disruption of helices H2, H3 and strands S3 and S4, whereas H6 was the last region exposed to solution and was the last helix to unfold. Moreover, simulations analyses combining with fluorescence and circular dichroism spectra indicated that N-domain could not fold independent, suggesting that correct folding of N-domain depended on its interactions with C-domain. We further proposed that the folding of GSTs could begin with the hydrophobic collapse of C-domain whose H4, H5, H6 and H7 could move close to each other and form a hydrophobic core, especially H6 wrapped in the hydrophobic center and beginning spontaneous formation of the helix. S3, S4, H3, and H2 could form in the wake of the interaction between C-domain and N-domain. The paper can offer insights into the molecular mechanism of GSTs unfolding. © 2014 Wiley Periodicals, Inc.

Glutathione S-transferase 4 is a putative DIF-binding protein that regulates the size of fruiting bodies in Dictyostelium discoideum.

PubMed

Kuwayama, Hidekazu; Kikuchi, Haruhisa; Oshima, Yoshiteru; Kubohara, Yuzuru

2016-12-01

In the development of the cellular slime mold Dictyostelium discoideum , two chlorinated compounds, the differentiation-inducing factors DIF-1 and DIF-2, play important roles in the regulation of both cell differentiation and chemotactic cell movement. However, the receptors of DIFs and the components of DIF signaling systems have not previously been elucidated. To identify the receptors for DIF-1 and DIF-2, we here performed DIF-conjugated affinity gel chromatography and liquid chromatography-tandem mass spectrometry and identified the glutathione S-transferase GST4 as a major DIF-binding protein. Knockout and overexpression mutants of gst4 ( gst4 - and gst4 OE , respectively) formed fruiting bodies, but the fruiting bodies of gst4 - cells were smaller than those of wild-type Ax2 cells, and those of gst4 OE cells were larger than those of Ax2 cells. Both chemotaxis regulation and in vitro stalk cell formation by DIFs in the gst4 mutants were similar to those of Ax2 cells. These results suggest that GST4 is a DIF-binding protein that regulates the sizes of cell aggregates and fruiting bodies in D. discoideum .

Phylogenetic analysis of the GST family in Anopheles (Nyssorhynchus) darlingi.

PubMed

Azevedo-Júnior, Gilson Martins de; Guimarães-Marques, Giselle Moura; Cegatti Bridi, Leticia; Christine Ohse, Ketlen; Vicentini, Renato; Tadei, Wanderli; Rafael, Míriam Silva

2014-08-01

Anopheles darlingi Root, 1926 and Anopheles gambiae (Diptera: Culicidae) are the most important human malaria vectors in South America and Africa, respectively. The two species are estimated to have diverged 100 million years ago. Studies on the phylogenetics and evolution of gene sequences, such as glutathione S-transferase (GST) in disease-transmitting mosquitoes are scarce. The sigma class GST (KC890767) from the transcriptome of An. darlingi captured in the Brazilian Amazon was studied by in silico hybridization, and mapped to chromosome 3 of An. gambiae. The sigma class GST of An. darlingi was used for phylogenetic analyses to understand the GST base composition of the most recent common ancestor between An. darlingi, Anopheles gambiae, Aedes aegypti and Culex quinquefasciatus. The GST (KC890767) of An. darlingi was studied to generate the main divergence branches using a Neighbor-Joining and bootstrapping approaches to confirm confidence levels on the tree nodes that separate the An. darlingi and other mosquito species. The results showed divergence between An. gambiae, Ae. Aegypti, Cx. quinquefasciatus, and Phlebotomus papatasi as outgroup, and the homology relationship between sigma class GST of An. darlingi and GSTS1_1 gene of An. gambiae was valuable for phylogenetic and evolutionary studies. Copyright © 2014 Elsevier B.V. All rights reserved.

Glutathione S-transferase iso-enzymes in perfusate from pumped kidneys are associated with delayed graft function.

PubMed

Hall, I E; Bhangoo, R S; Reese, P P; Doshi, M D; Weng, F L; Hong, K; Lin, H; Han, G; Hasz, R D; Goldstein, M J; Schröppel, B; Parikh, C R

2014-04-01

Accurate and reliable assessment tools are needed in transplantation. The objective of this prospective, multi-center study was to determine the associations of the alpha and pi iso-enzymes of glutathione S-transferase (GST), measured from perfusate solution at the start and end (base and post) of kidney allograft machine perfusion, with subsequent delayed graft function (DGF). We also compared GST iso-enzyme perfusate levels from discarded versus transplanted kidneys. A total of 428 kidneys were linked to outcomes as recorded by the United Network of Organ Sharing. DGF, defined as any dialysis in the first week of transplant, occurred in 141 recipients (32%). Alpha- and pi-GST levels significantly increased during machine perfusion. The adjusted relative risks (95% confidence interval) of DGF with each log-unit increase in base and post pi-GST were 1.14 (1.0-1.3) and 1.36 (1.1-1.8), respectively. Alpha-GST was not independently associated with DGF. There were no significant differences in GST values between discarded and transplanted kidneys, though renal resistance was significantly higher in discarded kidneys. We found pi-GST at the end of machine perfusion to be independently associated with DGF. Further studies should elucidate the utility of GST for identifying injured kidneys with regard to organ allocation, discard and recipient management decisions. © Copyright 2014 The American Society of Transplantation and the American Society of Transplant Surgeons.

Differences in glutathione S-transferase pi expression in transgenic mice with symptoms of neurodegeneration.

PubMed

Kaźmierczak, Beata; Kuźma-Kozakiewicz, Magdalena; Usarek, Ewa; Barańczyk-Kuźma, Anna

2011-01-01

Glutathione S-transferase pi (GST pi) is an enzyme involved in cell protection against toxic electrophiles and products of oxidative stress. GST pi expression was studied in transgenic mice hybrids (B6-C3H) with symptoms of neurodegeneration harboring SOD1G93A (SOD1/+), Dync1h1 (Cra1/+) and double (Cra1/SOD1) mutations, at presymptomatic and symptomatic stages (age 70, 140, 365 days) using RT-PCR and Western blotting. The main changes in GST pi expression were observed in mice with the SODG93A mutation. In SOD1/+ and Cra1/SOD1 transgenics, with the exception of cerebellum, the changes in GST pi-mRNA accompanied those in GST pi protein. In brain cortex of both groups the expression was unchanged at the presymptomatic (age 70 days) but was lower at the symptomatic stage (age 140 days) and at both stages in hippocampus and spinal cord of SOD1/+ but not of Cra1/SOD1 mice compared to age-matched wild-type controls. In cerebellum of the presymptomatic and the symptomatic SOD1/+ mice and presymptomatic Cra1/SOD1 mice, the GST pi-mRNA was drastically elevated but the protein level remained unchanged. In Cra1/+ transgenics there were no changes in GST pi expression in any CNS region both on the mRNA and on the protein level. It can be concluded that the SOD1G93A but not the Dync1h1 mutation significantly decreases detoxification efficiency of GST pi in CNS, however the Dync1h1 mutation reduces the effects caused by the SOD1G93A mutation. Despite similarities in neurological symptoms, the differences in GST pi expression between SOD1/+ and Cra1/+ transgenics indicate a distinct pathogenic entity of these two conditions.

Glutathione S-transferase PI (GST-PI) mRNA expression and DNA methylation is involved in the pathogenesis and prognosis of NSCLC.

PubMed

Grimminger, Peter P; Maus, Martin K H; Schneider, Paul M; Metzger, Ralf; Hölscher, Arnulf H; Sugita, Hirofumi; Danenberg, Peter V; Alakus, Hakan; Brabender, Jan

2012-10-01

The aim of this study was to investigate the relevance of mRNA expression and DNA methylation of GST-PI in tumor and non-tumor lung tissue from NSCLC patients in terms of prognostic and pathogenetic value of this biomarker. Quantitative real-time PCR was used to measure mRNA expression and DNA methylation of GST-PI in paired tumor (T) and non-tumor (N) lung tissue of 91 NSCLC patients. Of all 91 patients 49% were stage I, 21% stage II and 30% stage IIIA. Forty-seven percent of the patients had squamous cell carcinoma, 36% adenocarcinoma and 17% large cell carcinoma. All patients were R0 resected. GST-PI mRNA expression could be measured in 100% in both (T and N) tissues; GST-PI DNA methylation was detected in 14% (N) and 14% (T). The median GST-PI mRNA expression in N was 7.83 (range: 0.01-19.43) and in T 13.15 (range: 0.01-116.8; p≤0.001). The median GST-PI methylation was not significantly different between T and N. No associations were seen between the mRNA expression or DNA methylation levels and clinical or histopathologic parameters such as gender, age, TNM stage, tumor histology and grading. The median survival of the investigated patients was 59.7 years (the median follow-up was 85.9 months). High GST-PI DNA methylation was significantly associated with a worse prognosis (p=0.041, log rank test). No correlation was found between the GST-PI DNA methylation levels and the correlating mRNA expression levels. GST-PI mRNA expression seems to be involved in the pathogenesis of NSCLC. High levels of GST-PI DNA methylation in tumor tissue of NSCLC patients have a potential as a biomarker identifying subpopulations with a more aggressive tumor biology. Quantitation of GST-PI DNA methylation may be a useful method to identify patients with a poor prognosis after curative resection and who will benefit from intensive adjuvant therapy. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Molecular cloning, expression and enzymatic characterization of glutathione S-transferase from Antarctic sea-ice bacteria Pseudoalteromonas sp. ANT506.

PubMed

Shi, Yonglei; Wang, Quanfu; Hou, Yanhua; Hong, Yanyan; Han, Xiao; Yi, Jiali; Qu, Junjie; Lu, Yi

2014-01-01

A glutathione S-transferase (GST) gene from Antarctic sea-ice bacteria Pseudoalteromonas sp. ANT506 (namely PsGST), was cloned and expressed in Escherichia coli. The open reading frame of PsGST comprised 654 bp encoding a protein of 217 amino acids with a calculated molecular size of 24.3 kDa. The rPsGST possesses the conserved amino acid defining the binding sites of glutathione (G-site) and substrate binding pocket (H-site) in GST N_3 family. PsGST was expressed in E. coli and the recombinant PsGST (rPsGST) was purified by Ni-affinity chromatography with a high specific activity of 74.21 U/mg. The purified rPsGST showed maximum activity at 40 °C and exhibited 14.2% activity at 0 °C. It was completely inactivated at 50 °C for 40 min. These results indicated that rPsGST was a typical cold active GST with low thermostability. The enzyme was little affected by H2O2 and Triton X-100, and 50.2% of the remaining activity was detected in the presence of high salt concentrations (2M NaCl). The enzymatic Km values for CDNB and GSH was 0.22 mM and 1.01 mM, respectively. These specific enzyme properties may be related to the survival environment of Antarctic sea ice bacteria. Copyright © 2013 Elsevier GmbH. All rights reserved.

The role of glutathione S-transferases in the detoxification of some organophosphorus insecticides in larvae and pupae of the yellow mealworm, Tenebrio molitor (Coleoptera: Tenebrionidae).

PubMed

Kostaropoulos, I; Papadopoulos, A I; Metaxakis, A; Boukouvala, E; Papadopoulou-Mourkidou, E

2001-06-01

The correlation between the natural levels of glutathione S-transferase (GST) and the tolerance to the organophosphorus insecticides parathion-methyl and paraoxon-methyl, as well as the interaction of affinity-purified enzyme and the insecticides were investigated in order to collect further information on the role of the glutathione S-transferase system as a mechanism of defence against insecticides in insects. The studies were carried out on the larvae and pupae of the coleopteran Tenebrio molitor L, which exhibit varying natural levels of GST activity. Stage-dependent susceptibility of the insect against insecticides was observed during the first 24 h. However, 48 h after treatment, the KD50 value increased significantly due to the recovery of some individuals. Simultaneous injection of insecticide with compounds which inhibit GST activity in vitro caused an alteration in susceptibility of insects 24 or 48 h post-treatment, depending on stage and insecticide used. Inhibition studies combined with competitive fluorescence spectroscopy revealed that the insecticides probably bind to the active site of the enzyme, thus inhibiting its activity towards 1-chloro-2,4-dinitrobenzene in a competitive manner. High-performance liquid chromatography and gas chromatography revealed that T molitor GST catalyses the conjugation of the insecticides studied to a reduced form of glutathione (GSH). From the above experimental results, it is considered that GST offers a protection against the organophosphorus insecticides studied by active site binding and subsequent conjugation with GSH.

Ferrocene labelings as inhibitors and dual electrochemical sensors of human glutathione S-transferase P1-1.

PubMed

Martos-Maldonado, Manuel C; Quesada-Soriano, Indalecio; García-Maroto, Federico; Vargas-Berenguel, Antonio; García-Fuentes, Luís

2012-12-01

The inhibitory and sensor properties of two ferrocene conjugates, in which the ferrocene and glutathione are linked through a spacer arm of different length and chemical structure, on human Pi glutathione S-transferase, were examined by activity assays, ITC, fluorescence spectroscopy and voltammetry. Such ferrocene conjugates are strong competitive inhibitors of this enzyme with an enhanced binding affinity, the one bearing the longest spacer arm being the most potent inhibitor. Voltammetric measurements showed a strong decrease of the peak current intensity and an increase of the oxidation potential upon binding of ferrocene-glutathione conjugates to GST P1-1 showing that both conjugates can be used as dual electrochemical sensors for GST P1-1. Copyright © 2012 Elsevier Ltd. All rights reserved.

[Gene polymorphisms in patients with Down's syndrome].

PubMed

Kuz'mina, N S; Ushenkova, L I; Shagirova, Zh M; Sheĭkhaev, G O; Mikhaĭlov, V F; Kurbatova, L A; Mazurik, V K; Rubanovich, A V; Zasukhina, G D

2009-01-01

Polymorphisms of glutation-S-transferase (GSTM1, GSTT1 GSTP1) and methylentetrahydrofolate reductase (MTHFR) genes have been studied in DNA from blood lymphocytes of 18 patients with Down's syndrome and 61 controls. Frequencies of normal alleles of GST genotypes were lower in patients as compared to the controls. A DNA analysis of 11 patients and 17 controls revealed the presence of mutations in region 246-250 of exon 7 of the p53 gene in 4 patients. Mutations were not found in the control group. Due to the small sample size, the results of this study should be interpreted with caution and need replication in larger studies.

Expression of thymidylate synthase and glutathione-s-transferase pi in patients with esophageal squamous cell carcinoma.

PubMed

Huang, Jun-Xing; Li, Feng-Yue; Xiao, Wei; Song, Zheng-Xiang; Qian, Rong-Yu; Chen, Ping; Salminen, Eeva

2009-09-14

To investigate the expression of thymidylate synthase (TS) and glutathione-s-transferase pi (GST-pi) in esophageal squamous cell carcinoma and their association with the clinicopathologic characteristics. Immunohistochemical methods were used to detect the expression of TS and GST-pi in surgically resected formalin-fixed, paraffin-embedded esophageal squamous cell carcinoma (ESCC) tissue sections from 102 patients (median age, 58 years) and in 28 normal esophageal mucosa (NEM) samples. The relationship between TS and GST-pi expression and clinicopathologic factors was examined. The expression of TS and GST-pi was not statistically significantly associated with age of the patients, tumor size, lymph node metastasis, depth of invasion or tumor stage. TS staining was positive in 17.86% of normal esophageal mucosa and in 42.16% of ESCC samples (P < 0.05). The expression level of TS was not only significantly lower in well-differentiated (21.88%) than in poorly-differentiated carcinomas (51.43%, P < 0.05), but was also significantly higher in samples from male patients (46.51%) than from female patients (18.75%, P < 0.05). GST-pi was positively stained in 78.57% of normal esophageal mucosa and in 53.92% of ESCC samples (P < 0.05). The expression level of GST-pi was also significantly higher in well-differentiated carcinomas (65.63%) than in poorly-differentiated carcinomas (35.00%, P < 0.05). The expression of TS and of GST-pi may be used as molecular markers for the characterization of ESCC. Poorly-differentiated cells showed increased expression of TS and reduced expression of GST-pi.

Association study between GSTT1 and GSTM1 polymorphisms and risk of preeclampsia in Chinese population.

PubMed

Guan, Linbo; Fan, Ping; Liu, Xinghui; Liu, Rui; Chen, Yihong; Ye, Liyan; Chen, Jinxin; Zhu, Yue; Liu, Yu; Bai, Huai

2016-09-01

Preeclampsia is a pregnancy-specific disorder associated with oxidative stress. The glutathione S-transferases (GST) are a group of enzymes that protect cells from oxidative stress. Functional genetic polymorphisms of GST genes (GSTT1, GSTM1) have previously been reported. The aim of this study was to investigate the association of GST gene polymorphisms with the risk of preeclampsia in Chinese subjects. The case-control population consists of 525 subjects. The genotyping of the GSTT1 and GSTM1 polymorphisms was carried out on genomic DNA using the multiplex polymerase chain reaction (PCR). We calculated odds ratios (ORs), adjusted for the confounding variables, to estimate the association between gene polymorphisms and preeclampsia. The GSTT1 null genotype was found to be protective from the development of preeclampsia (odds ratios 0.645, 95% confidence interval 0.421-0.989; P=0.044). Further analysis showed that a combination of deletion genotypes of the GSTT1 and GSTM1 genes conferred an even lower risk of preeclampsia (OR=0.470, 95%CI=0.255-0.866; P=0.015). There is no relationship between the GSTT1 and GSTM1 gene polymorphisms and blood pressure levels in pregnant women with and without preeclampsia. Our data suggest that a GSTT1 null polymorphism might be associated with decreased risk for preeclampsia in the Chinese population, and that this risk decreases with the combination of both GSTT1 and GSTM1 null polymorphisms. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Glutathione and glutathione S-transferase levels in patients with liver metastases of colorectal cancer and other hepatic disorders.

PubMed

Baltruskeviciene, Edita; Kazbariene, Birutė; Badaras, Robertas; Bagdonaitė, Loreta; Krikštaponienė, Aurelija; Zdanavičius, Linas; Aleknavicius, Eduardas; Didziapetrienė, Janina

2016-07-01

Glutathione and glutathione S-transferases (GST) are involved in cell defence against reactive oxygen species, which induces oxidative stress and are associated with different chronic diseases. The aim of the present study was to determine the differences in reduced glutathione (GSH) and GST levels in patients with different liver diseases. Overall, 114 patients were enrolled in this study: 58 patients with colorectal cancer (18 without and 40 with liver metastases), 27 with liver steatosis, 29 with alcoholic cirrhosis and a group of 40 healthy volunteers. The levels of GSH and GST in blood serum were evaluated by enzyme-linked immunosorbent assay (ELISA) according to the manufacturer's guidelines. Significant differences in GSH and GST levels were observed in most of the groups compared to the healthy volunteers (GSH: 52.72 µg/mL, GST: 0.53 ng/mL): with hepatic steatosis (GSH: 17.04 µg/mL, p < 0.001; GST: 5.89 ng/mL, p < 0.001), alcoholic cirrhosis (GSH: 62.04 µg/mL, p < 0.003; GST: 0.94 ng/mL, p < 0.001) and liver metastases (GSH: 37.84 µg/mL, p < 0.001, GST: 1.25 ng/mL, p=0.747). The different GSH and GST levels in patients with colorectal cancer liver metastases, liver steatosis and alcoholic cirrhosis indicate the differences in antioxidative system damage and its compensatory possibilities and could serve as potential biomarkers for its correction.

Role of glutathione S-transferase Pi in cisplatin-induced nephrotoxicity.

PubMed

Townsend, Danyelle M; Tew, Kenneth D; He, Lin; King, Jarrod B; Hanigan, Marie H

2009-02-01

One of the dose-limiting toxicities of cisplatin is nephrotoxicity. Renal toxicity is localized to quiescent proximal tubule cells, where the formation of DNA-adducts cannot account for the dose-limiting toxicity. Our earlier results have shown that a glutathione conjugate of cisplatin is metabolized to a nephrotoxicant via gamma-glutamyl transpeptidase (GGT) and a cysteine S-conjugate beta-lyase. The present study was designed to evaluate the potential role of glutathione S-transferase Pi (GSTP) in the initial steps of the bioactivation of cisplatin. Wild-type mice and mice deficient in both murine GSTP genes (GstP1/P2) were treated with cisplatin. Toxicity in both male and female mice was evaluated 5 days after treatment and renal damage was most severe in wild-type male mice. Wild-type males have approximately 10-fold higher levels of GSTP expression in the liver than females, suggesting that hepatic GSTP in the wild-type males contributed to the formation of the nephrotoxic platinum-glutathione conjugate. In GstP1/P2 null mice the gender difference in toxicity was eliminated. Our data show that GSTP expression is a determinant in cisplatin-induced nephrotoxicity and its levels contribute to sex-dependent differences.

Role of Glutathione S-Transferase Pi in Cisplatin Induced Nephrotoxicity

PubMed Central

Townsend, Danyelle M.; Tew, Kenneth D.; He, Lin; King, Jarrod B.; Hanigan, Marie H.

2009-01-01

SUMMARY One of the dose-limiting toxicities of cisplatin is nephrotoxicity. Renal toxicity is localized to quiescent proximal tubule cells, where the formation of DNA-adducts cannot account for the dose-limiting toxicity. Our earlier results have shown that a glutathione-conjugate of cisplatin is metabolized to a nephrotoxicant via gamma-glutamyltranspeptidase (GGT) and a cysteine S-conjugate beta-lyase. The present study was designed to evaluate the potential role of glutathione-S-transferase Pi (GSTP) in the initial steps of the bioactivation of cisplatin. Wild-type mice and mice deficient in both murine GSTP genes (GstP1/P2) were treated with cisplatin. Toxicity in both male and female mice was evaluated 5 days after treatment and renal damage was most severe in wild-type male mice. Wild-type males have ~10-fold higher levels of GSTP expression in the liver than females, suggesting that hepatic GSTP in the wild-type males contributed to the formation of the nephrotoxic platinum-glutathione conjugate. In GstP1/P2 null mice the gender difference in toxicity was eliminated. Our data show that GSTP expression is a determinant in cisplatin-induced nephrotoxicity and its levels contribute to sex-dependent differences. PMID:18819770

Association of glutathione S-transferase P1 (GSTP1) polymorphism with Tourette syndrome in Taiwanese patients.

PubMed

Shen, Che-Piao; Chou, I-Ching; Liu, Hsin-Ping; Lee, Cheng-Chun; Tsai, Yuhsin; Wu, Bor-Tsang; Hsu, Ban-Dar; Lin, Wei-Yong; Tsai, Fuu-Jen

2014-01-01

The etiology of Tourette syndrome (TS) is multifactorial. TS vulnerability may be associated with genetic and environmental factors. From the genetic point of view, TS is heterogeneous. Previous studies showed that some single-nucleotide polymorphisms (SNPs) of the glutathione-S-transferase P1 (GSTP1) gene can affect cellular proliferation and apoptotic activity and TS is a neurodevelopmental disorder. We guessed that there was a relationship between TS and genetic variants of the GSTP1 gene. Therefore, in this study, we aimed to test the hypothesis that GSTP1 SNPs were associated with TS. We performed a case-control study. One hundred twenty-one TS children and 105 normal children were included in the study. Polymerase chain reaction was used to identify the GSTP1 gene polymorphism at position rs6591256 (A/G, promoter polymorphism) in TS patients and normal children. The polymorphism at position rs6591256 in the GSTP1 gene revealed significant differences in the allele (p=0.0135) and genotype (p=0.0159) distributions between the TS patients and the control group. The A allele was present at a higher frequency than the G allele in the TS patients compared with the control group (odds ratio [OR]=1.91, 95% confidence interval [CI]: 1.14-3.21). The AA genotype was associated with susceptibility to TS with an OR of 2.38 for the AA versus AG genotype (95% CI: 1.29-4.41). These findings suggest that variants in the GSTP1 gene may play a role in susceptibility to TS.

Association of glutathione S-transferase pi (GSTP1) Ile105Val polymorphism with the risk of skin cancer: a meta-analysis.

PubMed

Zhou, Cheng-Fan; Ma, Tai; Zhou, Deng-Chuan; Shen, Tong; Zhu, Qi-Xing

2015-08-01

Numerous epidemiological studies have evaluated the association of Glutathione S-transferase P1 (GSTP1) Ile105Val polymorphism with the risk of skin cancer. However, the results remain inconclusive. To derive a more precise estimation of the association between the GSTP1 Ile105Val polymorphism and skin cancer risk, a meta-analysis was performed. A comprehensive search was conducted to identify the eligible studies. We used odds ratios (ORs) with 95 % confidence intervals (CIs) to assess the association of GSTP1 Ile105Val polymorphism with skin cancer risk. Thirteen case-control studies in nine articles, which included a total of 1504 cases and 2243 controls. Overall, we found that GSTP1 Ile105Val polymorphism was not associated with skin cancer risk. Furthermore, subgroup analysis by histological types showed that GSTP1 Ile105Val polymorphism was associated with risks of malignant melanoma under the dominant model (Val/Val + Val/Ile vs. Ile/Ile: OR 1.230, 95 % CI 1.017-1.488, P = 0.033). However, lack of association between GSTP1 Ile105Val polymorphism and BCC and SCC risk in all genetic models. Our meta-analysis suggested that the GSTP1 Ile105Val polymorphism might be associated with increased risk of malignant melanoma in Caucasian population.

Glutathione-S-transferase P protects against endothelial dysfunction induced by exposure to tobacco smoke.

PubMed

Conklin, Daniel J; Haberzettl, Petra; Prough, Russell A; Bhatnagar, Aruni

2009-05-01

Exposure to tobacco smoke impairs endothelium-dependent arterial dilation. Reactive constituents of cigarette smoke are metabolized and detoxified by glutathione-S-transferases (GSTs). Although polymorphisms in GST genes are associated with the risk of cancer in smokers, the role of these enzymes in regulating the cardiovascular effects of smoking has not been studied. The P isoform of GST (GSTP), which catalyzes the conjugation of electrophilic molecules in cigarette smoke such as acrolein, was expressed in high abundance in the mouse lung and aorta. Exposure to tobacco smoke for 3 days (5 h/day) decreased total plasma protein. These changes were exaggerated in GSTP(-/-) mice. Aortic rings isolated from tobacco smoke-exposed GSTP(-/-) mice showed greater attenuation of ACh-evoked relaxation than those from GSTP(+/+) mice. The lung, plasma, and aorta of mice exposed to tobacco smoke or acrolein (for 5 h) accumulated more acrolein-adducted proteins than those tissues of mice exposed to air, indicating that exposure to tobacco smoke results in the systemic delivery of acrolein. Relative to GSTP(+/+) mice, modification of some proteins by acrolein was increased in the aorta of GSTP(-/-) mice. Aortic rings prepared from GSTP(-/-) mice that inhaled acrolein (1 ppm, 5 h/day for 3 days) or those exposed to acrolein in an organ bath showed diminished ACh-induced arterial relaxation more strongly than GSTP(+/+) mice. Acrolein-induced endothelial dysfunction was prevented by pretreatment of the aorta with N-acetylcysteine. These results indicate that GSTP protects against the endothelial dysfunction induced by tobacco smoke exposure and that this protection may be related to the detoxification of acrolein or other related cigarette smoke constituents.

Prevalence of glutathione S-transferase gene deletions and their effect on sickle cell patients.

PubMed

Sanjay, Pandey; Mani, Mishra Rahasy; Sweta, Pandey; Vineet, Shah; Kumar, Ahuja Rajesh; Renu, Saxena

2012-01-01

Glutathione S-transferase gene deletions are known detoxification agents and cause oxidative damage. Due to the different pathophysiology of anemia in thalassemia and sickle cell disease, there are significant differences in the pathophysiology of iron overload and iron-related complications in these disorders. The aim of this study was to estimate the frequency of the GSTM1 and GSTT1 genotypes in sickle cell disease patients and their effect on iron status. Forty sickle cell anemia and sixty sickle ß-thalassemia patients and 100 controls were evaluated to determine the frequency of GST gene deletions. Complete blood counts were performed by an automated cell analyzer. Hemoglobin F, hemoglobin A, hemoglobin A2 and hemoglobin S were measured and diagnosis of patients was achieved by high performance liquid chromatography with DNA extraction by the phenol-chloroform method. The GST null genotype was determined using multiplex polymerase chain reaction and serum ferritin was measured using an ELISA kit. Statistical analysis was by EpiInfo and GraphPad statistics software. An increased frequency of the GSTT1 null genotype (p-value = 0.05) was seen in the patients. The mean serum ferritin level was higher in patients with the GST genotypes than in controls; this was statistically significant for all genotypes except GSTM1, however the higher levels of serum ferritin were due to blood transfusions in patients. GST deletions do not play a direct role in iron overload of sickle cell patients.

Limonin Methoxylation Influences Induction of Glutathione S-Transferase and Quinone Reductase

PubMed Central

PEREZ, JOSE LUIS; JAYAPRAKASHA, G. K.; VALDIVIA, VIOLETA; MUNOZ, DIANA; DANDEKAR, DEEPAK V.; AHMAD, HASSAN; PATIL, BHIMANAGOUDA S.

2009-01-01

Previous studies have indicated the chemoprevention potential of citrus limonoids due to the induction of phase II detoxifying enzymes. In the present study, three citrus limonoids were purified and identified from sour orange seeds as limonin, limonin glucoside (LG), deacetylnomilinic acid glucoside (DNAG). In addition, limonin was modified to defuran limonin and limonin 7-methoxime. The structures of these compounds were confirmed by NMR studies. These five compounds were used to investigate the influence of Phase II enzymes in female A/J mice. Our results indicated that the highest induction of Glutathione S-Transferase (GST) activity against 1-chloro-2, 4-dinitrobenzene (CDNB) by DNAG (67%) in lung homogenates followed by limonin-7-methoxime (32%) in treated liver homogenates. Interestingly, the limonin-7-methoxime showed the highest GST activity (270%) in liver against 4-nitroquinoline 1-oxide (4NQO), while the same compound in stomach induced GST by 51% compared to the control. DNAG treated group induced 55% in stomach homogenates. Another Phase II enzyme, quinone reductase (QR), was significantly induced by limonin-7-methoxime by 65 and 32% in liver and lung homogenates, respectively. Defuran limonin, induced QR in lung homogenates by 45%. Our results indicated that modification of the limonin have differential induction of phase II enzymes. These findings are indicative of a possible mechanism for the prevention of cancer by aiding in detoxification of xenobiotics. PMID:19480426

INDUCTION OF DNA-PROTEIN CROSSLINKS BY THE METABOLISM OF DICHLOROMETHANE IN V79 CELL LINES TRANSFECTED WITH THE MURINE GLUTATHIONE-S-TRANSFERASE THETA 1 GENE

EPA Science Inventory

Dichloromethane (DCM) is considered a probable human carcinogen. Laboratory studies have shown an increased incidence of lung and liver cancer in mice but not in rats or hamsters. Despite the correlation between metabolism of DCM by the glutathione-S-transferase (GST) pathway and...

The relationship between changes in functional cardiac parameters following anthracycline therapy and carbonyl reductase 3 and glutathione S transferase Pi polymorphisms.

PubMed

Volkan-Salanci, Bilge; Aksoy, Hakan; Kiratli, Pınar Özgen; Tülümen, Erol; Güler, Nilüfer; Öksüzoglu, Berna; Tokgözoğlu, Lale; Erbaş, Belkıs; Alikaşifoğlu, Mehmet

2012-10-01

The aim of this prospective clinical study is to evaluate the relationship between changes in functional cardiac parameters following anthracycline therapy and carbonyl reductase 3 (CBR3p.V244M) and glutathione S transferase Pi (GSTP1p.I105V) polymorphisms. Seventy patients with normal cardiac function and no history of cardiac disease scheduled to undergo anthracycline chemotherapy were included in the study. The patients' cardiac function was evaluated by gated blood pool scintigraphy and echocardiography before and after chemotherapy, as well as 1 year following therapy. Gene polymorphisms were genotyped in 70 patients using TaqMan probes, validated by DNA sequencing. A deteriorating trend was observed in both systolic and diastolic parameters from GG to AA in CBR3p.V244M polymorphism. Patients with G-allele carriers of GSTP1p.I105V polymorphism were common (60%), with significantly decreased PFR compared to patiens with AA genotype. Variants of CBR3 and GSTP1 enzymes may be associated with changes in short-term functional cardiac parameters.

Association of genetic polymorphism of glutathione S-transferase (GSTM1, GSTT1, GSTP1) with bladder cancer susceptibility.

PubMed

Safarinejad, Mohammad Reza; Safarinejad, Saba; Shafiei, Nayyer; Safarinejad, Shiva

2013-10-01

The glutathione-S-transferases (GSTs) comprise a class of enzymes that detoxify carcinogenic compounds by conjugating glutathione to facilitate their removal. Polymorphisms in GSTM1, GSTT1, and GSTP1 genes have been related to risk for bladder cancer. Studies focusing on GSTs gene variants relationship with the risk of bladder cancer have produced conflicting and inconsistent results. We examine the association between genetic polymorphism of glutathione S-transferase P1, GSTM1, GSTT1 genes and development of bladder transitional cell carcinoma (TCC). The study population consisted of 166 histologically confirmed male bladder TCC cases and 332 healthy male controls. Genotyping was done using the polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) method and also investigated combined gene interactions. The GSTP1 Val/Val genotype was significantly associated with bladder cancer (OR = 4.32, 95% CI: 2.64-6.34), whereas the association observed for GSTM1 null (OR = 1.32, 95% CI: 0.82-2.62; P = 0.67) and GSTT1 null genotype (OR = 1.18, 95% CI: 0.79-1.67; P = 0.74) did not reach statistical significance. There was a significant multiple interaction between GSTM1, GSTT1, and GSTP1 genotypes in risk of bladder cancer (P for interaction = 0.02). The risk associated with the concurrent presence of GSTM1 positive and GSTP1 Ile/Val or Val/Val (OR = 3.71, 95% CI: 2.34-5.54) and GSTT1 positive and GSTP1 Ile/Val or Val/Val (OR = 2.66, 95% CI: 1.54-4.72) was statistically significant. Patients carrying GSTP1 Val/Val genotype were at increased risk for developing high-grade (OR = 7.68, 95% CI: 4.73-19.25) and muscle invasive (OR = 10.67, 95% CI: 6.34-21.75) bladder cancer. High risk for bladder TCC also was observed with respect to combined GSTT1 null/GSTP1 Ile/Val or Val/Val (OR = 4.76, 95% CI: 2.68-18.72) and GSTM1 null/GSTT1 null/GSTP1 Ile/Val or Val/Val (OR = 6.42, 95% CI: 4.76-14.72) genotype variant. This study suggests that the GSTP1 polymorphism

Possible prenatal impact of sertraline on human placental glutathione S-transferase-π.

PubMed

Dalmizrak, O; Kulaksiz-Erkmen, G; Ozer, N

2012-05-01

Sertraline (SER), a tricyclic antidepressant, is considered to belong to the group of selective amine reuptake inhibitors. Its ability to cross the blood-brain barrier and transplacental transport has been reported previously. It is widely distributed in the brain and is bound to human glutathione S-transferase-π (GST-π). If SER is taken during pregnancy, it gets accumulated in the embryo and fetus, and some studies have suggested it may cause congenital malformations, thus the study of the interaction of GST-π with antidepressants is crucial. In this study, the interaction of human placental GST-π with SER in the presence of the natural ligand, reduced glutathione (GSH) and a xenobiotic ligand, 1-chloro-2,4-dinitrobenzene (CDNB) was investigated. The V(m) values obtained at variable [CDNB] and variable [GSH] were 61.3 ± 2.3 and 46.4 ± 1.7 U/mg protein, respectively. The k(cat) and k(cat)/K(m) values for GSH and CDNB were 3.63 × 10(6) s(-1), 2.59 × 10(10) M(-1) s(-1) and 4.79 × 10(6) s(-1), 1.29 × 10(10) M(-1) s(-1), respectively. The half maximal inhibitory concentration value for SER was 4.60 mM. At constant [CDNB] and variable [GSH] the inhibition type was linear mixed-type, with K(s), α, and K(i) values of 0.14 ± 0.02, 2.90 ± 1.64, and 2.18 ± 0.80 mM, respectively. On the other hand, at fixed [GSH] and at variable [CDNB], the inhibition type was competitive, with K(i) value of 0.96 ± 0.10 mM. Thus, these findings weaken the importance of the protective role of GST against toxic electrophiles in vivo in adults, but due to its immature enterohepatic system SER may accumulate in the fetus and cause congenital malformations.

Glutathione S-transferase M1 and T1 Polymorphisms, Cigarette Smoking and HPV Infection in Precancerous and Cancerous Lesions of the Uterine Cervix.

PubMed

Sharma, Anita; Gupta, Sanjay; Sodhani, Pushpa; Singh, Veena; Sehgal, Ashok; Sardana, Sarita; Mehrotra, Ravi; Sharma, Joginder Kumar

2015-01-01

Glutathione S-transferases (GSTs) play an important role in detoxification of carcinogenic electrophiles. The null genotypes in GSTM1 and GSTT1 have been implicated in carcinogenesis. Present study was planned to evaluate the influence of genetic polymorphisms of GSTM1 and GSTT1 gene loci in cervical carcinogenesis. The study was conducted in Lok Nayak hospital, New Delhi. DNA from clinical scrapes of 482 women with minor gynaecologic complaints attending Gynaecology OPD and tumor biopsies of 135 cervical cancer cases attending the cancer clinic was extracted. HPV DNA was detected by standard polymerase chain reaction (PCR) using L1 consensus primer pair. Polymorphisms of GSTM1 and GSTT1 were analysed by multiplex PCR procedures. Differences in proportions were tested using Pearson's Chi-square test with Odds ratio (OR) and 95% confidence interval (CI). The risk of cervical cancer was almost three times in women with GSTM1 homozygous null genotype (OR-2.62, 95%CI, 1.77-3.88; p<0.0001). No association of GSTM1 or GSTT1 homozygous null genotypes was observed in women with normal, precancerous and cervical cancerous lesions among ≤35 or >35 years of age groups. Smokers with null GSTT1 genotype had a higher risk of cervical cancer as compared to non-smokers (OR-3.01, 95% CI, 1.10-8.23; p=0.03). The results further showed that a significant increased risk of cervical cancer was observed in HPV positive smoker women with GSTT1 (OR-4.36, 95% CI, 1.27-15.03; p=0.02) and GSTM1T1 (OR-3.87, 95% CI, 1.05-14.23; p=0.04) homozygous null genotypes as compared to HPV positive non smokers. The results demonstrate that the GST null genotypes were alone not associated with the development of cervical cancer, but interacted with smoking and HPV to exert effects in our Delhi population.

In silico genome-wide identification and characterization of the glutathione S-transferase gene family in Vigna radiata.

PubMed

Vaish, Swati; Awasthi, Praveen; Tiwari, Siddharth; Tiwari, Shailesh Kumar; Gupta, Divya; Basantani, Mahesh Kumar

2018-05-01

Plant glutathione S-transferases (GSTs) are integral to normal plant metabolism and biotic and abiotic stress tolerance. The GST gene family has been characterized in diverse plant species using molecular biology and bioinformatics approaches. In the current study, in silico analysis identified 44 GSTs in Vigna radiata. Of the total 44 GSTs identified, chromosomal locations of 31 GSTs were confirmed. The pI value of GST proteins ranged from 5.10 to 9.40. The predicted molecular weights ranged from 13.12 to 50 kDa. Subcellular localization analysis revealed that all GSTs were predominantly localized in the cytoplasm. The active site amino acids were confirmed to be serine in tau, phi, theta, zeta, and TCHQD; cysteine in lambda, DHAR, and omega; and tyrosine in EF1G. The gene architecture conformed to the two-exon/one-intron and three-exon/two-intron organization in the case of tau and phi classes, respectively. MEME analysis identified 10 significantly conserved motifs with the width of 8-50 amino acids. The motifs identified were either specific to a specific GST class or were shared by multiple GST classes. The results of the current study will be of potential importance in the characterization of the GST gene family in V. radiata, an economically important leguminous crop.

Germline glutathione S-transferase variants in breast cancer: Relation to diagnosis and cutaneous long-term adverse effects after two fractionation patterns of radiotherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Edvardsen, Hege; Kristensen, Vessela N.; Medical Faculty, University of Oslo, Oslo

Purpose: To explore whether certain glutathione S-transferase (GST) polymorphisms are associated with an increased risk of breast cancer or the level of radiation-induced adverse effects after two fractionation patterns of adjuvant radiotherapy. Methods and Materials: The prevalence of germline polymorphic variants in GSTM1, GSTP1, and GSTT1 was determined in 272 breast cancer patients and compared with that in a control group of 270 women from the general population with no known history of breast cancer. The genetic variants were determined using multiplex polymerase chain reaction followed by restriction enzyme fragment analysis. In 253 of the patients surveyed for radiotherapy-induced sidemore » effects after a median observation time of 13.7 years (range, 7-22.8 years), the genotypes were related to the long-term effects observed after two fractionation patterns (treatment A, 4.3 Gy in 10 fractions for 156 patients; and treatment B, 2.5 Gy in 20 fractions for 97; both administered within a 5-week period). Results: None of the GST polymorphisms conferred an increased risk of breast cancer, either alone or in combination. Compared with treatment B, treatment A was followed by an increased level of moderate to severe radiation-induced side effects for all the endpoints studied (i.e., degree of telangiectasia, subcutaneous fibrosis and atrophy, lung fibrosis, costal fractures, and pleural thickening; p <0.001 for all endpoints). A significant association was found between the level of pleural thickening and the GSTP1 Ile105Val variant. Conclusion: The results of this study have illustrated the impact of hypofractionation on the level of adverse effects and indicated that the specific alleles of GSTP1, M1, and T1 studied here may be significant in determining the level of adverse effects after radiotherapy.« less

Involvement of glutathione/glutathione S-transferase antioxidant system in butyrate-inhibited vascular smooth muscle cell proliferation.

PubMed

Ranganna, Kasturi; Mathew, Omana P; Yatsu, Frank M; Yousefipour, Zivar; Hayes, Barbara E; Milton, Shirlette G

2007-11-01

Vascular smooth muscle cell (VSMC) proliferation is an important etiological factor in vascular proliferative diseases such as primary atherosclerosis, hypertension, arterial and in-stent restenosis, and transplant vasculopathy. Our studies established that butyrate, a bacterial fermentation product of dietary fiber and a chromatin modulator, is a potent inhibitor of VSMC proliferation. The cardiovascular health benefits of a high-fiber diet, the principle source of butyrate in the body, have been known for a long time, however, very little is known about the antiatherogenic potential of butyrate. Because oxidative stress plays an important role in the pathogenesis of atherosclerosis, we examined involvement of the glutathione/glutathione S-transferase (GST) antioxidant system in butyrate's inhibition of VSMC proliferation. Treatment of proliferating VSMCs with butyrate leads to the induction of several GSTs. Interestingly, our study also demonstrated the nuclear localization of GST-P1 (GST-7-7), which is considered to be a cytosolic protein; this was demonstrated using immunostaining and was corroborated by western blotting. Also, the butyrate-induced antiproliferative action, and the induction of GST-P1 and its nuclear localization are downregulated when butyrate is withdrawn. Furthermore, assessment of intracellular glutathione levels reveals their augmentation by butyrate. Conversely, butyrate treatment reduces the levels of reactive oxygen species in VSMCs. Collectively, the butyrate-treatment-related increase in glutathione content, the reduction in reactive oxygen species, the upregulation of GST and the nuclear localization of GST-P1 in growth-arrested VSMCs imply that butyrate's antiproliferative action involves modulation of the cellular redox state. Thus, induction of the glutathione/GST antioxidant system appears to have other regulatory role(s) besides detoxification and regulation of the cellular redox state, for example, cell-cycle control and cell

Purification and properties of the glutathione S-transferases from the anoxia-tolerant turtle, Trachemys scripta elegans.

PubMed

Willmore, William G; Storey, Kenneth B

2005-07-01

Glutathione S-transferases (GSTs) play critical roles in detoxification, response to oxidative stress, regeneration of S-thiolated proteins, and catalysis of reactions in nondetoxification metabolic pathways. Liver GSTs were purified from the anoxia-tolerant turtle, Trachemys scripta elegans. Purification separated a homodimeric (subunit relative molecular mass =34 kDa) and a heterodimeric (subunit relative molecular mass = 32.6 and 36.8 kDa) form of GST. The enzymes were purified 23-69-fold and 156-174-fold for homodimeric and heterodimeric GSTs, respectively. Kinetic data gathered using a variety of substrates and inhibitors suggested that both homodimeric and heterodimeric GSTs were of the alpha class although they showed significant differences in substrate affinities and responses to inhibitors. For example, homodimeric GST showed activity with known alpha class substrates, cumene hydroperoxide and p-nitrobenzylchloride, whereas heterodimeric GST showed no activity with cumene hydroperoxide. The specific activity of liver GSTs with chlorodinitrobenzene (CDNB) as the substrate was reduced by 2.6- and 8.7-fold for homodimeric and heterodimeric GSTs isolated from liver of anoxic turtles as compared with aerobic controls, suggesting an anoxia-responsive stable modification of the protein that may alter its function during natural anaerobiosis.

Purification of Glutathione S-Transferase pi from Erythrocytes and Evaluation of the Inhibitory Effect of Hypericin.

PubMed

Turk, Seyhan; Kulaksiz Erkmen, Gulnihal; Dalmizrak, Ozlem; Ogus, I Hamdi; Ozer, Nazmi

2015-12-01

Hypericin is a photosensitizer compound used in the photodynamic therapy (PDT). PDT is an alternative cancer treatment strategy whose function is dependent on the photosensitizers accumulating selectively in tumor cells and following visible or infra-red light induced activation lead to the apoptosis/necrosis of the tumor cells via the formation of reactive oxygen species. Thus, the cellular redox balance is essential for the efficacy of PDT. Among the protective enzyme systems glutathione S-transferases (GST, E.C.2.5.1.18) function in detoxification, protection against oxidative stress and intracellular transport of molecules. It is known that isoenzymes of GST and especially GST-pi is increased in cancer cells and it plays very important functions in the development of resistance to anticancer drugs. Since photosensitizers are used intravenously, it is important to elucidate the effects of photosensitizers on the erythrocyte enzymes. The aim of the present study was to investigate the impact of hypericin on human erythrocyte GST-pi (heGST-pi). Purification yield of 71% and purification fold of 2550 were achieved by using conventional chromatographic methods. The specific activity of the enzyme is found as 51 U/mg protein. Hypericin inhibited heGST-pi in a dose dependent manner and inhibition was biphasic. Noncompetitive type of inhibition was observed with both substrates, GSH and CDNB. The inhibitory constant (K i ) values obtained from Lineweaver-Burk, Dixon, secondary plots; slope and y-intercept versus 1/S (substrate) and from non-linear regression analysis were in good correlation: K i (GSH) was calculated as 0.19 ± 0.01 μM and K i (CDNB) as 0.26 ± 0.03 μM.

Effect of recombinant glutathione S-transferase as vaccine antigen against Rhipicephalus appendiculatus and Rhipicephalus sanguineus infestation.

PubMed

Sabadin, Gabriela Alves; Parizi, Luís Fernando; Kiio, Irene; Xavier, Marina Amaral; da Silva Matos, Renata; Camargo-Mathias, Maria Izabel; Githaka, Naftaly Wang'ombe; Nene, Vish; da Silva Vaz, Itabajara

2017-12-04

The ticks Rhipicephalus appendiculatus and Rhipicephalus sanguineus are the main vectors of Theileria parva and Babesia spp. in cattle and dogs, respectively. Due to their impact in veterinary care and industry, improved methods against R. appendiculatus and R. sanguineus parasitism are under development, including vaccines. We have previously demonstrated the induction of a cross-protective humoral response against Rhipicephalus microplus following vaccination with recombinant glutathione S-transferase from Haemaphysalis longicornis tick (rGST-Hl), suggesting that this protein could control tick infestations. In the present work, we investigated the effect of rGST-Hl vaccine against R. appendiculatus and R. sanguineus infestation in rabbits. In silico analysis revealed that GST from H. longicornis, R. appendiculatus and R. sanguineus have >80% protein sequence similarity, and multiple conserved antigenic sites. After the second vaccine dose, rGST-Hl-immunized rabbits showed elevated antibody levels which persisted until the end of experiment (75 and 60 days for R. appendiculatus and R. sanguineus, respectively). Western blot assays demonstrated cross-reactivity between anti-rGST-Hl antibodies and native R. appendiculatus and R. sanguineus GST extracts from ticks at different life stages. Vaccination with rGST-Hl decreased the number, weight, and fertility of engorged R. appendiculatus adults, leading to an overall vaccine efficacy of 67%. Interestingly, histological analysis of organ morphology showed damage to salivary glands and ovaries of R. appendiculatus adult females fed on vaccinated animals. In contrast, rGST-Hl vaccination did not affect R. appendiculatus nymphs, and it was ineffective against R. sanguineus across the stages of nymph and adult. Taken together, our results show the potential application of rGST-Hl as an antigen in anti-tick vaccine development, however indicating a broad difference in efficacy among tick species. Copyright © 2017 Elsevier

Glutathione S-transferase M1-null genotype as risk factor for SOS in oxaliplatin-treated patients with metastatic colorectal cancer.

PubMed

Vreuls, C P H; Olde Damink, S W M; Koek, G H; Winstanley, A; Wisse, E; Cloots, R H E; van den Broek, M A J; Dejong, C H C; Bosman, F T; Driessen, A

2013-02-19

Oxaliplatin is used as a neo-adjuvant therapy in hepatic colorectal carcinoma metastasis. This treatment has significant side effects, as oxaliplatin is toxic to the sinusoidal endothelial cells and can induce sinusoidal obstruction syndrome (SOS), which is related to decreased overall survival. Glutathione has an important role in the defence system, catalysed by glutathione S-transferase (GST), including two non-enzyme producing polymorphisms (GSTM1-null and GSTT1-null). We hypothesise that patients with a non-enzyme producing polymorphism have a higher risk of developing toxic injury owing to oxaliplatin. In the nontumour-bearing liver, the presence of SOS was studied histopathologically. The genotype was determined by a semi-nested PCR. Thirty-two of the 55 (58%) patients showed SOS lesions, consisting of 27% mild, 22% moderate and 9% severe lesions. The GSTM1-null genotype was present in 25 of the 55 (46%). Multivariate analysis showed that the GSTM1-null genotype significantly correlated with the presence of (moderate-severe) SOS (P=0.026). The GSTM1-null genotype is an independent risk factor for SOS. This finding allows us, in association with other risk factors, to conceive a potential risk profile predicting whether the patient is at risk of developing SOS, before starting oxaliplatin, and subsequently might result in adjustment of treatment.

Glutathione S-transferases in human renal cortex and neoplastic tissue: enzymatic activity, isoenzyme profile and immunohistochemical localization.

PubMed

Rodilla, V; Benzie, A A; Veitch, J M; Murray, G I; Rowe, J D; Hawksworth, G M

1998-05-01

1. Glutathione S-transferase (GST) activity in the cytosol of renal cortex and tumours from eight men and eight women was measured using 1-chloro-2,4-dinitrobenzene (CDNB) as a substrate. GST activities ranged from 685 to 2192 nmol/min/mg protein in cortex (median 1213) and from non-detectable (minimum 45) to 2424 nmol/min/mg protein in tumours (median 469). The activities in the tumours were lower than those in the normal cortices (p < 0.05). 2. In men, the activity in the cortical cytosol was in all cases higher than that measured in the corresponding tumours (p < 0.05). In women, the difference in activity between cortices and tumours was not significantly different (p > 0.05). 3. The age of the patients ranged from 42 to 81 years (median 62) and was not found to play a role in the levels of GST activity observed in cortex or in renal tumours from either sex. 4. Immunoblotting and immunohistochemical studies confirmed that GST-alpha was the predominant form expressed both in normal cortex and tumour and probably accounted for most of the GST activity present in these samples. GST-mu and GST-phi were expressed in both tumours and normal cortex and, while in some cases the level of expression in the cortices was higher than that found in the tumours, the reverse was also observed. Within the GST-mu class, GST M1/M2 was only detected in one sample (tumour), which showed the highest overall expression of GST-mu. GSTM3 was the predominant isoenzyme of the mu class in normal and tumour tissue, whereas GTM4 and GSTM5 were not detected. 5. These differences could have functional significance where xenobiotics or cytotoxic drugs are specific substrates for the different classes of GSTs.

Fish hepatic glutathione-S-transferase activity is affected by the cestode parasites Schistocephalus solidus and Ligula intestinalis: evidence from field and laboratory studies.

PubMed

Frank, Sabrina Nadine; Faust, Steffen; Kalbe, Martin; Trubiroha, Achim; Kloas, Werner; Sures, Bernd

2011-06-01

The activity of hepatic glutathione-S-transferase (GST) was analysed in 3 different fish species with respect to fish sex and infection with parasites. In both sexes of laboratory bred three-spined sticklebacks (Gasterosteus aculeatus) experimentally infected with Schistocephalus solidus (Cestoda), a significantly lower GST-activity was found for infected fish compared to control. After field sampling of roach (Rutilus rutilus) from Lake Müggelsee (MS) and the Reservoir Listertalsperre (LTS), the GST-activity showed significantly lower values for males infected with Ligula intestinalis from MS (25%) and for infected females from LTS (55%). L. intestinalis-infected female chub (Leuciscus cephalus) from LTS also appeared to have a lower GST-activity. Thus, it could be shown that the presence of parasites significantly affects GST-activity in different fish species resulting in a decreased GST-activity due to infection. Our results therefore emphasize the need for more integrative approaches in environmental pollution research to clearly identify the possible effects of parasites in an effort to develop biomarkers for evaluating environmental health.

Decreased Glutathione S-transferase Level and Neonatal Hyperbilirubinemia Associated with Glucose-6-phosphate Dehydrogenase Deficiency: A Perspective Review.

PubMed

Al-Abdi, Sameer Yaseen

2017-02-01

Classically, genetically decreased bilirubin conjugation and/or hemolysis account for the mechanisms contributing to neonatal hyperbilirubinemia associated with glucose-6-phosphate dehydrogenase (G6PD) deficiency. However, these mechanisms are not involved in most cases of this hyperbilirubinemia. Additional plausible mechanisms for G6PD deficiency-associated hyperbilirubinemia need to be considered. Glutathione S-transferases (GST) activity depends on a steady quantity of reduced form of glutathione (GSH). If GSH is oxidized, it is reduced back by glutathione reductase, which requires the reduced form of nicotinamide adenine dinucleotide phosphate (NADPH). The main source of NADPH is the pentose phosphate pathway, in which G6PD is the first enzyme. Rat kidney GSH, rat liver GST, and human red blood cell GST levels have been found to positively correlate with G6PD levels in their respective tissues. As G6PD is expressed in hepatocytes, it is expected that GST levels would be significantly decreased in hepatocytes of G6PD-deficient neonates. As hepatic GST binds bilirubin and prevents their reflux into circulation, hypothesis that decreased GST levels in hepatocytes is an additional mechanism contributing to G6PD deficiency-associated hyperbilirubinemia seems plausible. Evidence for and against this hypothesis are discussed in this article hoping to stimulate further research on the role of GST in G6PD deficiency-associated hyperbilirubinemia. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Effects of imidacloprid on detoxifying enzyme glutathione S-transferase on Folsomia candida (Collembola).

PubMed

Sillapawattana, Panwad; Schäffer, Andreas

2017-04-01

Chemical analyses of the environment can document contamination by various xenobiotics, but it is also important to understand the effect of pollutants on living organisms. Thus, in the present work, we investigated the effect of the pesticide imidacloprid on the detoxifying enzyme glutathione S-transferase (GST) from Folsomia candida (Collembola), a standard test organism for estimating the effects of pesticides and environmental pollutants on non-target soil arthropods. Test animals were treated with different concentrations of imidacloprid for 48 h. Changes in steady-state levels of GST messenger RNA (mRNA) and GST enzyme activity were investigated. Extracted proteins were separated according to their sizes by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and the resolved protein bands were detected by silver staining. The size of the glutathione (GSH) pool in Collembola was also determined. A predicted protein sequence of putative GSTs was identified with animals from control group. A 3-fold up-regulation of GST steady-state mRNA levels was detected in the samples treated with 5.0 mg L -1 imidacloprid compared to the control, while a 2.5- and 2.0- fold up-regulation was found in organisms treated with 2.5 and 7.5 mg L -1 imidacloprid, respectively. GST activity increased with increasing imidacloprid amounts from an initial activity of 0.11 μmol min -1  mg -1 protein in the control group up to 0.25 μmol min -1  mg -1 protein in the sample treated with the 5.0 mg L -1 of pesticide. By contrast, the total amount of GSH decreased with increasing imidacloprid concentration. The results suggest that the alteration of GST activity, steady-state level of GST mRNA, and GSH level may be involved in the response of F. candida to the exposure of imidacloprid and can be used as biomarkers to monitor the toxic effects of imidacloprid and other environmental pollutants on Collembola.

Polymorphisms of glutathione S-transferase π 1 and toll-like receptors 2 and 9: Association with breast cancer susceptibility

PubMed Central

AL-HARRAS, MOHAMMAD F.; HOUSSEN, MAHA E.; SHAKER, MOHAMED E.; FARAG, KAMEL; FAROUK, OMAR; MONIR, REHAN; EL-MAHDY, RASHA; ABO-HASHEM, EKBAL M.

2016-01-01

Polymorphisms in antioxidant enzymes and innate immune receptors have been implicated in the development of various types of cancer. The present study aimed to investigate whether polymorphisms of glutathione S-transferase π 1 (GSTP1) and toll-like receptors (TLRs) 2 and 9 are associated with susceptibility to breast cancer among females. The study was conducted on 72 Egyptian female patients with breast cancer, along with 100 healthy volunteers. Polymorphisms of GSTP1 (codon 105 Ile/Val) and TLR9 rs187084 (1237T/C) genes were assessed by polymerase chain reaction (PCR)-restriction fragment length polymorphism, while the −196 to −174 deletion/insertion (del/ins) polymorphism of TLR2 was detected by PCR. The results indicated a decrease in GSTP1 Val allele frequency in breast cancer patients compared with healthy controls, at rates of 22.9 vs. 32.5%, respectively. In addition, the breast cancer group demonstrated a decreased TLR9 C allele frequency compared with the control group, at rates of 36.1 vs. 51.5%, respectively (P=0.0047). A non-significant difference was detected in the frequency of the TLR2 −196 to −174 del allele in breast cancer patients when compared to normal controls. In conclusion, these results suggested that the GSTP1 Val and TLR9 1237C alleles, but not TLR2 −196 to −174 del, are likely to be associated with breast cancer development among females. PMID:26998146

Polymorphisms of glutathione S-transferase π 1 and toll-like receptors 2 and 9: Association with breast cancer susceptibility.

PubMed

Al-Harras, Mohammad F; Houssen, Maha E; Shaker, Mohamed E; Farag, Kamel; Farouk, Omar; Monir, Rehan; El-Mahdy, Rasha; Abo-Hashem, Ekbal M

2016-03-01

Polymorphisms in antioxidant enzymes and innate immune receptors have been implicated in the development of various types of cancer. The present study aimed to investigate whether polymorphisms of glutathione S-transferase π 1 (GSTP1) and toll-like receptors (TLRs) 2 and 9 are associated with susceptibility to breast cancer among females. The study was conducted on 72 Egyptian female patients with breast cancer, along with 100 healthy volunteers. Polymorphisms of GSTP1 (codon 105 Ile/Val) and TLR9 rs187084 (1237T/C) genes were assessed by polymerase chain reaction (PCR)-restriction fragment length polymorphism, while the -196 to -174 deletion/insertion (del/ins) polymorphism of TLR2 was detected by PCR. The results indicated a decrease in GSTP1 Val allele frequency in breast cancer patients compared with healthy controls, at rates of 22.9 vs. 32.5%, respectively. In addition, the breast cancer group demonstrated a decreased TLR9 C allele frequency compared with the control group, at rates of 36.1 vs. 51.5%, respectively (P=0.0047). A non-significant difference was detected in the frequency of the TLR2 -196 to -174 del allele in breast cancer patients when compared to normal controls. In conclusion, these results suggested that the GSTP1 Val and TLR9 1237C alleles, but not TLR2 -196 to -174 del, are likely to be associated with breast cancer development among females.

Association of N-acetyltransferase-2 and glutathione S-transferase polymorphisms with idiopathic male infertility in Vietnam male subjects.

PubMed

Trang, Nguyen Thi; Huyen, Vu Thi; Tuan, Nguyen Thanh; Phan, Tran Duc

2018-04-25

N-acetyltransferase-2 (NAT2) and Glutathione S-transferases (GSTs) are phase-II xenobiotic metabolizing enzymes participating in detoxification of toxic arylamines, aromatic amines, hydrazines and reactive oxygen species (ROS), which are produced under oxidative and electrophile stresses. The purpose of this research was to investigate whether two common single-nucleotide polymorphisms (SNP) of NAT2 (rs1799929, rs1799930) and GSTP1 (rs1138272, rs1695) associated with susceptibility to idiopathic male infertility. A total 300 DNA samples (150 infertile patients and 150 healthy control) were genotyped for the polymorphisms by ARMS - PCR. We revealed a significant association between the NAT2 variant genotypes (CT + TT (rs1799929), (OR: 3.74; p < 0.001)) and (GA + AA (rs1799930), (OR: 3.75; p < 0.001)) or GSTP1 variant genotypes (GA + AA (rs1695), (OR: 5.11; p < 0,001)) and (CT + TT (rs1138272), (OR: 7.42; p < 0,001) with idiopathic infertility risk. Our findings rate the effect of single-nucleotide polymorphisms of GSTP1 and/or NAT2 in modulation of the risk of male infertility in subjects from Vietnam. This pilot study is the first (as far as we know) to reveal that polymorphisms of NAT2 (rs1799929, rs1799930) and GSTP1 (rs1138272, rs1695) are some novel genetic markers for susceptibility to idiopathic male infertility. Copyright © 2018 Elsevier B.V. All rights reserved.

A study of the association of glutathione S-transferase M1/T1 polymorphisms with susceptibility to vitiligo in Egyptian patients.

PubMed

Aly, Dalia Gamal; Salem, Samar Abdallah; Amr, Khalda Sayed; El-Hamid, Mahmoud Fawzy Abd

2018-01-01

The association of glutathione S-transferases M1/T1 (GSTM1/T1) null polymorphisms with vitiligo was proposed in several studies including two Egyptian studies with contradictory results. The aim here was to assess the association between GSTM1/T1 null polymorphisms and the susceptibility to vitiligo in a larger sample of Egyptian patients with generalized vitiligo. This study included 122 vitiligo patients and 200 healthy controls that were age, and gender matched. Assessment of GSTM1/T1 gene polymorphisms was done using a multiplex polymerase chain reaction (PCR). Increased odds of generalized vitiligo was observed with the null genotypes of GSTM1 and GSTT1 polymorphisms (P<0.05). Controls with GSTM1 null/GSTT1+ heterozygosis presented with a 2.97 odds protection from having generalized vitiligo (OR=2.97, 95%CI=1.1-7.7) (P=0.02) compared with patients. Small sample size of patients. This study showed a significant trend towards an association with the combination of the GSTM1/GSTT1 double null polymorphism and generalized vitiligo. Individuals with GSTM1 null/GSTT1+ heterozygosis have a 2.97 odds protection from having generalized vitiligo compared with patients. It was is the first time, to our knowledge, that such an association has been reported.

Recombinant human glutathione S-transferases catalyse enzymic isomerization of 13-cis-retinoic acid to all-trans-retinoic acid in vitro.

PubMed Central

Chen, H; Juchau, M R

1998-01-01

The steric conversion of 13-cis-retinoic acid (13-cRA) to all-trans-retinoic acid (t-RA) has been proposed as an activation mechanism for the observed therapeutic and teratogenic activities of 13-cRA. Here we have investigated the catalysis of isomerization of 13-cRA to t-RA by recombinant human glutathione S-transferases (GSTs). Substrate was incubated with GST in 0.1 M sodium phosphate buffer, pH 7.5, at 37 degrees C in total darkness. The t-RA generated was measured quantitatively by HPLC. Under the reaction conditions used, GSTP1-1 was far more effective than human GSTM1-1 or human GSTA1-1 in catalysing the isomerization reaction. The reaction catalysed by GSTP1-1 showed substrate saturation and the Km and Vmax values for the reaction were approx. 7 microM and 650 pmol/min per nmol respectively. The reaction rate increased linearly with increasing enzyme concentration. The reaction was inhibited both by heat treatment and by S-decylglutathione (a potent inhibitor of transferase activity associated with GST). Additions of polyclonal rabbit antiserum for human GSTP1-1 to the reaction resulted in a significant decrease in generation of t-RA (70-80%). In addition, ethacrynic acid, a selective substrate for Pi isoforms of GST, also inhibited the isomerization of 13-cRA to t-RA catalysed by GSTP1-1. Under the same reaction conditions, GSTP1-1 was much less effective in catalysing the steric conversion of 9-cis-retinoic acid to t-RA, indicating that the enzyme was stereospecific for the conversion of 13-cRA to t-RA. These observations suggest that enzymic catalysis was the primary mechanism for the GSTP1-1-dependent conversion of 13-cRA to t-RA. Reactions catalysed by a purified rat hepatic GST Pi isoenzyme proceeded more slowly than reactions catalysed by human GSTP1-1. Comparative studies also showed that there were marked species differences in catalytic activities between various purified mammalian hepatic GST mixtures. PMID:9806904

Recombinant human glutathione S-transferases catalyse enzymic isomerization of 13-cis-retinoic acid to all-trans-retinoic acid in vitro.

PubMed

Chen, H; Juchau, M R

1998-11-15

The steric conversion of 13-cis-retinoic acid (13-cRA) to all-trans-retinoic acid (t-RA) has been proposed as an activation mechanism for the observed therapeutic and teratogenic activities of 13-cRA. Here we have investigated the catalysis of isomerization of 13-cRA to t-RA by recombinant human glutathione S-transferases (GSTs). Substrate was incubated with GST in 0.1 M sodium phosphate buffer, pH 7.5, at 37 degrees C in total darkness. The t-RA generated was measured quantitatively by HPLC. Under the reaction conditions used, GSTP1-1 was far more effective than human GSTM1-1 or human GSTA1-1 in catalysing the isomerization reaction. The reaction catalysed by GSTP1-1 showed substrate saturation and the Km and Vmax values for the reaction were approx. 7 microM and 650 pmol/min per nmol respectively. The reaction rate increased linearly with increasing enzyme concentration. The reaction was inhibited both by heat treatment and by S-decylglutathione (a potent inhibitor of transferase activity associated with GST). Additions of polyclonal rabbit antiserum for human GSTP1-1 to the reaction resulted in a significant decrease in generation of t-RA (70-80%). In addition, ethacrynic acid, a selective substrate for Pi isoforms of GST, also inhibited the isomerization of 13-cRA to t-RA catalysed by GSTP1-1. Under the same reaction conditions, GSTP1-1 was much less effective in catalysing the steric conversion of 9-cis-retinoic acid to t-RA, indicating that the enzyme was stereospecific for the conversion of 13-cRA to t-RA. These observations suggest that enzymic catalysis was the primary mechanism for the GSTP1-1-dependent conversion of 13-cRA to t-RA. Reactions catalysed by a purified rat hepatic GST Pi isoenzyme proceeded more slowly than reactions catalysed by human GSTP1-1. Comparative studies also showed that there were marked species differences in catalytic activities between various purified mammalian hepatic GST mixtures.

A novel biomarker for marine environmental pollution of pi-class glutathione S-transferase from Mytilus coruscus.

PubMed

Liu, Huihui; He, Jianyu; Zhao, Rongtao; Chi, Changfeng; Bao, Yongbo

2015-08-01

Glutathione S-transferases (GSTs) are the superfamily of phase II detoxification enzymes that play crucial roles in innate immunity. In this study, a pi-class GST homolog was identified from Mytilus coruscus (named as McGST1, KC525103). The full-length cDNA sequence of McGST1 was 621bp with a 5' untranslated region (UTR) of 70bp and a 3'-UTR of 201bp. The deduced amino acid sequence was 206 residues in length with theoretical pI/MW of 5.60/23.72kDa, containing the conserved G-site and diversiform H-site. BLASTn analysis and phylogenetic relationship strongly suggested that this cDNA sequence was a member of pi class GST family. The prediction of secondary structure displayed a preserved N-terminal and a C-terminal comprised with α-helixes. Quantitative real time RT-PCR showed that constitutive expression of McGST1 was occurred, with increasing order in mantle, muscle, gill, hemocyte, gonad and hepatopancreas. The stimulation of bacterial infection, heavy metals and 180CST could up-regulate McGST1 mRNA expression in hepatopancreas with time-dependent manners. The maximum expression appeared at 6h after pathogenic bacteria injected, with 10-fold in Vibrio alginolyticus and 16-fold in Vibrio harveyi higher than that of the control. The highest point of McGST1 mRNA appeared at different time for exposure to copper (10-fold at day 15), cadmium (9-fold at day10) and 180 CST (10-fold at day 15). These results suggested that McGST1 played a significant role in antioxidation and might potentially be used as indicators and biomarkers for detection of marine environmental pollution. Copyright © 2015 Elsevier Inc. All rights reserved.

Chaperone activity of human small heat shock protein-GST fusion proteins.

PubMed

Arbach, Hannah; Butler, Caley; McMenimen, Kathryn A

2017-07-01

Small heat shock proteins (sHsps) are a ubiquitous part of the machinery that maintains cellular protein homeostasis by acting as molecular chaperones. sHsps bind to and prevent the aggregation of partially folded substrate proteins in an ATP-independent manner. sHsps are dynamic, forming an ensemble of structures from dimers to large oligomers through concentration-dependent equilibrium dissociation. Based on structural studies and mutagenesis experiments, it is proposed that the dimer is the smallest active chaperone unit, while larger oligomers may act as storage depots for sHsps or play additional roles in chaperone function. The complexity and dynamic nature of their structural organization has made elucidation of their chaperone function challenging. HspB1 and HspB5 are two canonical human sHsps that vary in sequence and are expressed in a wide variety of tissues. In order to determine the role of the dimer in chaperone activity, glutathione-S-transferase (GST) was genetically linked as a fusion protein to the N-terminus regions of both HspB1 and HspB5 (also known as Hsp27 and αB-crystallin, respectively) proteins in order to constrain oligomer formation of HspB1 and HspB5, by using GST, since it readily forms a dimeric structure. We monitored the chaperone activity of these fusion proteins, which suggest they primarily form dimers and monomers and function as active molecular chaperones. Furthermore, the two different fusion proteins exhibit different chaperone activity for two model substrate proteins, citrate synthase (CS) and malate dehydrogenase (MDH). GST-HspB1 prevents more aggregation of MDH compared to GST-HspB5 and wild type HspB1. However, when CS is the substrate, both GST-HspB1 and GST-HspB5 are equally effective chaperones. Furthermore, wild type proteins do not display equal activity toward the substrates, suggesting that each sHsp exhibits different substrate specificity. Thus, substrate specificity, as described here for full-length GST

Multiple glutathione S-transferase genes: identification and expression in oriental fruit fly, Bactrocera dorsalis.

PubMed

Hu, Fei; Dou, Wei; Wang, Jing-Jing; Jia, Fu-Xian; Wang, Jin-Jun

2014-02-01

The oriental fruit fly, Bactrocera dorsalis (Hendel), is widely distributed in Asia-Pacific regions, where it is a serious pest of a wide range of tropical and subtropical fruit and vegetable crops. In this study, 17 cDNA encoding glutathione S-transferases (GSTs) in B. dorsalis were sequenced and characterised. Phylogenetic analysis revealed that 16 GSTs belonged to five different cytosolic classes, including four in delta, eight in epsilon, two in omega, one in theta, and one in zeta. The remaining GST (BdGSTu1) was unclassified. RT-qPCR assay showed that the relative expression levels of five GST genes were significantly higher in larval stages than in adulthood. Tissue-specific expression analysis found that BdGSTe3, BdGSTe9 and BdGSTd5 were expressed highly in the midgut, BdGSTe4, BdGSTe6, BdGSTd6 and BdGSTz2 were higher in the fat body, and six GSTs were higher in Malpighian tubules. RT-qPCR confirmed that the expressions of nine GST genes were increased by malathion exposure at various times and doses, while BdGSTe4, BdGSTe9 and BdGSTt1 were increased by β-cypermethrin exposure. The increases in GST gene expression levels after malathion and β-cypermethrin exposure in B. dorsalis might increase the ability of this species to detoxify other insecticides and xenobiotics. © 2013 Society of Chemical Industry.

Primary and secondary structural analyses of glutathione S-transferase pi from human placenta.

PubMed

Ahmad, H; Wilson, D E; Fritz, R R; Singh, S V; Medh, R D; Nagle, G T; Awasthi, Y C; Kurosky, A

1990-05-01

The primary structure of glutathione S-transferase (GST) pi from a single human placenta was determined. The structure was established by chemical characterization of tryptic and cyanogen bromide peptides as well as automated sequence analysis of the intact enzyme. The structural analysis indicated that the protein is comprised of 209 amino acid residues and gave no evidence of post-translational modifications. The amino acid sequence differed from that of the deduced amino acid sequence determined by nucleotide sequence analysis of a cDNA clone (Kano, T., Sakai, M., and Muramatsu, M., 1987, Cancer Res. 47, 5626-5630) at position 104 which contained both valine and isoleucine whereas the deduced sequence from nucleotide sequence analysis identified only isoleucine at this position. These results demonstrated that in the one individual placenta studied at least two GST pi genes are coexpressed, probably as a result of allelomorphism. Computer assisted consensus sequence evaluation identified a hydrophobic region in GST pi (residues 155-181) that was predicted to be either a buried transmembrane helical region or a signal sequence region. The significance of this hydrophobic region was interpreted in relation to the mode of action of the enzyme especially in regard to the potential involvement of a histidine in the active site mechanism. A comparison of the chemical similarity of five known human GST complete enzyme structures, one of pi, one of mu, two of alpha, and one microsomal, gave evidence that all five enzymes have evolved by a divergent evolutionary process after gene duplication, with the microsomal enzyme representing the most divergent form.

A meta-analysis of association between glutathione S-transferase M1 gene polymorphism and Parkinson's disease susceptibility.

PubMed

Weikang, Chen; Jie, Li; Likang, Lan; Weiwen, Qiu; Liping, Lu

2016-01-01

The aim of this meta-analysis was to evaluate whether there was an association between glutathione S-transferase M1(GSTM1)gene polymorphism and Parkinson's disease (PD) susceptibility by pooling published data. We performed comprehensive electronic database search for articles published between February12,2015 and April30 2016. The published case-control or cohort studies related to GSTM1 gene polymorphism and Parkinson's disease susceptibility were screened, reviewed, and included in this meta-analysis. The correlation between GSTM1 gene polymorphism and PD susceptibility was expressed by odds ratio (OR) and its corresponding 95% confidence interval (95%CI). Publication bias was evaluated by Begg's funnel plot and Egger's line regression test. All analysis was done by stata11.0 software. After searching the PubMed, EMBASE, and CNKI databases, seventeen case-control studies with 3,538 PD and 5,180 controls were included in the final meta-analysis. The data was pooled by a fixed-effect model for lack of statistical heterogeneity across the studies; the results showed GSTM1 null expression can significant increase the susceptibility of PD (OR=1.11, 95% CI:1.01-1.21, P<0.05). Subgroup analysis indicated GSTM1 gene polymorphism was associated with PD susceptibility in the Caucasian ethnic group (OR=1.15, 95% CI:1.05-1.27, P<0.05) but not in the Asian ethnic group (OR=0.89, 95% CI:0.70-1.12, P>0.05). Begg's funnel plot and Egger's line regression test showed no significant publication bias. Based on the present evidence, GSTM1 null expression can significant increase the susceptibility of PD in persons of Caucasian ethnicity.

Green tea consumption and glutathione S-transferases genetic polymorphisms on the risk of adult leukemia.

PubMed

Liu, Ping; Zhang, Min; Xie, Xing; Jin, Jie; Holman, C D'Arcy J

2017-03-01

Green tea may have a beneficial role of inhibiting leukemia. Glutathione S-transferases (GSTs) are known to detoxify certain carcinogens. We investigated the roles of green tea consumption and polymorphisms of GSTM1, GSTT1 and GSTP1 on the risk of adult leukemia, and to determine whether the associations varied within GSTs genotypes. A multicenter case-control study was conducted in China, 2008-2013. It comprised 442 incident, hematologically confirmed adult leukemia cases and 442 outpatient controls, individually matched to cases by gender, birth quinquennium and study site. Data were collected by face-to-face interview using a validated questionnaire. Genetic polymorphisms were assayed by PCR. An inverse association between green tea consumption and adult leukemia risk was observed. Compared with non-tea drinkers, the adjusted odds ratios (95 % confidence intervals) were 0.50 (0.27-0.93), 0.31 (0.17-0.55) and 0.53 (0.29-0.99) for those who, respectively, consumed green tea >20 years, ≥2 cups daily and dried tea leaves >1000 g annually. In assessing the associations by GSTs genotypes, risk reduction associated with green tea consumption was stronger in individuals with the GSTT1-null genotype (OR 0.24; 95 % CI 0.11-0.53) than GSTT1-normal carriers (OR 0.67; 95 % CI 0.42-1.05; P interaction = 0.02). GSTM1 and GSTP1 did not significantly modify the inverse association of leukemia with green tea. The results suggest that regular daily green tea consumption may reduce leukemia risk in Chinese adults regardless of GSTM1 and GSTP1 polymorphic status. The association between green tea and adult leukemia risk varied with GSTT1 genotype and highlights further study.

Yeast one-hybrid system used to identify the binding proteins for rat glutathione S-transferase P enhancer I.

PubMed

Liao, Ming-Xiang; Liu, Dong-Yuan; Zuo, Jin; Fang, Fu-De

2002-03-01

To detect the trans-factors specifically binding to the strong enhancer element (GPEI) in the upstream of rat glutathione S-transferase P (GST-P) gene. Yeast one-hybrid system was used to screen rat lung MATCHMAKER cDNA library to identify potential trans-factors that can interact with core sequence of GPEI(cGPEI). Electrophoresis mobility shift assay (EMSA) was used to analyze the binding of transfactors to cGPEI. cDNA fragments coding for the C-terminal part of the transcription factor c-Jun and rat adenine nucleotide translocator (ANT) were isolated. The binding of c-Jun and ANT to GPEI core sequence were confirmed. Rat c-jun transcriptional factor and ANT may interact with cGPEI. They could play an important role in the induced expression of GST-P gene.

Measurement of glutathione S-transferase and its class-pi in plasma and tissue biopsies obtained after laparoscopy and endoscopy from subjects with esophagus and gastric cancer.

PubMed

Mohammadzadeh, G S; Nasseri Moghadam, S; Rasaee, M J; Zaree, A B; Mahmoodzadeh, H; Allameh, A

2003-06-01

To develop an indirect enzyme-linked immunosorbent assay (ELISA) for measuring class-pi glutathione S-transferase (GST) in plasma, and tissue biopsies obtained from upper gastrointestinal cancer (UGI Ca) patients. GST activity and GST-pi concentration were detected in normal human squamous esophageal epithelium, normal gastric cardia and their corresponding malignant tumor biopsies. Plasma GST was significantly higher (p < 0.05) in UGI Ca patients as compared to those obtained from normal individuals. Plasma GST-pi concentration in normal subjects was 6.6 +/- 1.9 ng/mg protein, whereas it was higher in UGI Ca patients (esophageal, 10.0 +/- 1.8; gastric, 10.7 +/- 1.7 ng/mL, p GST and GST-pi levels were higher in surgically resected tumor biopsies as compared to normal tissues adjacent to a tumor (p < 0.05). GST-pi was also elevated in malignant esophagus and gastric biopsies taken at endoscopy as compared to normal and normal-appearing esophageal tissues (p < 0.05). Total GST was also increased significantly in gastric malignant tissues although its activity was within the same range in normal and normal-appearing tissues. A significant correlation between plasma GST-pi with that in malignant tissues was observed. Total GST and GST-pi were also correlated in different malignant tissues. Biopsies obtained at endoscopy can be used satisfactorily to measure tumor markers.

The inhibition characteristics of human placental glutathione S-transferase-π by tricyclic antidepressants: amitriptyline and clomipramine.

PubMed

Dalmizrak, Ozlem; Kulaksiz-Erkmen, Gulnihal; Ozer, Nazmi

2011-09-01

Tricyclic antidepressants (TCAs) are the non-selective amine re-uptake inhibitors, well absorbed from small intestine, cross the blood-brain barrier, distributed in the brain, and are bound to glutathione S-transferase-π (GST-π). TCAs can pass through placenta, accumulate in utero baby, and cause congenital malformations. Thus, the study of the interaction of GST-π with antidepressants is crucial. In this study, the interaction of GST-π with amitriptyline and clomipramine was investigated. The K (m) values for glutathione (GSH) and 1-chloro-2,4-dinitrobenzene (CDNB) were found to be 0.16 ± 0.04 and 3.60 ± 1.67 mM, respectively. The V (m) values were varying according to the fixed substrate; [CDNB] fixed, 53 ± 3 and [GSH] fixed 182 ± 63 U/mg protein. At variable [GSH] and variable [CDNB], the k (cat) values of 7.0 × 10(6) and 1.42 × 10(7) s(-1) and the k (cat)/K (m) values of 4.38 × 10(10) and 3.94 × 10(9 )M(-1 )s(-1) were obtained, respectively. At fixed [CDNB] and variable [GSH], amitriptyline (K (s) = 0.16 ± 0.03 mM; α = 2.08; and K (i) = 1.75 ± 0.37 mM) and clomipramine (K (s) = 0.24 ± 0.05 mM; α = 1.57; and K (i) = 3.90 ± 2.26 mM) showed linear mixed-type inhibition whereas when the varied substrate is CDNB, amitriptyline (K (i) = 4.90 ± 0.68 mM) and clomipramine (K (i) = 3.37 ± 0.39 mM) inhibition were noncompetitive. The inhibition of GST-π by TCAs means the destruction of its protective role against toxic electrophiles. The effect of antidepressants on fetus will be much severe, thus, the antidepressant therapy of pregnant women should be done with caution.

Modulatory influence of sandalwood oil on mouse hepatic glutathione S-transferase activity and acid soluble sulphydryl level.

PubMed

Banerjee, S; Ecavade, A; Rao, A R

1993-02-01

The effect of the oil from the wood of Santalum album on glutathione S-transferase (GST) activity and acid soluble sulphydryl (SH) levels in the liver of adult male Swiss albino mice was investigated. Oral feeding by gavage to mice each day with 5 and 15 microliters sandalwood oil for 10 and 20 days exhibited an increase in GST activity in time- and dose-responsive manners. Feeding a dose of 5 microliters sandalwood oil for 10 and 20 days caused, respectively, a 1.80-fold (P < 0.001) and 1.93-fold (P < 0.001) increase in GST enzyme activity, while feeding a dose of 15 microliters of the oil per day for 10 and 20 days induced, respectively, 4.73-fold (P < 0.001) and 6.10-fold (P < 0.001) increases in the enzyme's activity. In addition, there were 1.59-fold (P < 0.001) and 1.57 (P < 0.001) increases in acid-soluble SH levels in the hepatic tissue of the mice following feeding of the oil at the dose levels of 5 and 15 microliters for 10 days. Furthermore, mice fed on a diet containing 1% 2(3)-butyl-4-hydroxyanisole (positive control) also showed an increase in hepatic GST activity and SH levels. Enhancement of GST activity and acid-soluble SH levels are suggestive of a possible chemopreventive action of sandalwood oil on carcinogenesis through a blocking mechanism.

Genetic polymorphisms in glutathione-S-transferases are associated with anxiety and mood disorders in nicotine dependence

PubMed Central

Pizzo de Castro, Márcia Regina; Ehara Watanabe, Maria Angelica; Losi Guembarovski, Roberta; Odebrecht Vargas, Heber; Vissoci Reiche, Edna Maria; Kaminami Morimoto, Helena; Dodd, Seetal; Berk, Michael

2014-01-01

Background Nicotine dependence is associated with an increased risk of mood and anxiety disorders and suicide. The primary hypothesis of this study was to identify whether the polymorphisms of two glutathione-S-transferase enzymes (GSTM1 and GSTT1 genes) predict an increased risk of mood and anxiety disorders in smokers with nicotine dependence. Materials and methods Smokers were recruited at the Centre of Treatment for Smokers. The instruments were a sociodemographic questionnaire, Fagerström Test for Nicotine Dependence, diagnoses of mood disorder and nicotine dependence according to DSM-IV (SCID-IV), and the Alcohol, Smoking and Substance Involvement Screening Test. Anxiety disorder was assessed based on the treatment report. Laboratory assessment included glutathione-S-transferases M1 (GSTM1) and T1 (GSTT1), which were detected by a multiplex-PCR protocol. Results Compared with individuals who had both GSTM1 and GSTT1 genes, a higher frequency of at least one deletion of the GSTM1 and GSTT1 genes was identified in anxious smokers [odds ratio (OR)=2.21, 95% confidence interval (CI)=1.05–4.65, P=0.034], but there was no association with bipolar and unipolar depression (P=0.943). Compared with nonanxious smokers, anxious smokers had a greater risk for mood disorders (OR=4.67; 95% CI=2.24–9.92, P<0.001), lung disease (OR=6.78, 95% CI=1.95–23.58, P<0.003), and suicide attempts (OR=17.01, 95% CI=2.23–129.91, P<0.006). Conclusion This study suggests that at least one deletion of the GSTM1 and GSTT1 genes represents a risk factor for anxious smokers. These two genes may modify the capacity for the detoxification potential against oxidative stress. PMID:24637631

Photoaffinity labelling of the active site of the rat glutathione transferases 3-3 and 1-1 and human glutathione transferase A1-1.

PubMed

Cooke, R J; Björnestedt, R; Douglas, K T; McKie, J H; King, M D; Coles, B; Ketterer, B; Mannervik, B

1994-09-01

The glutathione transferases (GSTs) form a group of enzymes responsible for a wide range of molecular detoxications. The photoaffinity label S-(2-nitro-4-azidophenyl)glutathione was used to study the hydrophobic region of the active site of the rat liver GST 1-1 and 2-2 isoenzymes (class Alpha) as well as the rat class-Mu GST 3-3. Photoaffinity labelling was carried out using a version of S-(2-nitro-4-azidophenyl)glutathione tritiated in the arylazido ring. The labelling occurred with higher levels of radioisotope incorporation for the Mu than the Alpha families. Taking rat GST 3-3, 1.18 (+/- 0.05) mol of radiolabel from S-(2-nitro-4-azidophenyl)glutathione was incorporated per mol of dimeric enzyme, which could be blocked by the presence of the strong competitive inhibitor, S-tritylglutathione (Ki = 1.4 x 10(-7) M). Radiolabelling of the protein paralleled the loss of enzyme activity. Photoaffinity labelling by tritiated S-(2-nitro-4-azidophenyl)glutathione on a preparative scale (in the presence and absence of S-tritylglutathione) followed by tryptic digestion and purification of the labelled peptides indicated that GST 3-3 was specifically photolabelled; the labelled peptides were sequenced. Similarly, preparative photoaffinity labelling by S-(2-nitro-4-azidophenyl)glutathione of the rat liver 1-1 isoenzyme, the human GST A1-1 and the human-rat chimaeric GST, H1R1/1, was carried out with subsequent sequencing of radiolabelled h.p.l.c.-purified tryptic peptides. The results were interpreted by means of molecular-graphics analysis to locate photoaffinity-labelled peptides using the X-ray-crystallographic co-ordinates of rat GST 3-3 and human GST A1-1. The molecular-graphical analysis indicated that the labelled peptides are located within the immediate vicinity of the region occupied by S-substituted glutathione derivatives bound in the active-site cavity of the GSTs investigated.

Differential expression of glutathione s-transferase enzyme in different life stages of various insecticide-resistant strains of Anopheles stephensi: a malaria vector.

PubMed

Sanil, D; Shetty, V; Shetty, N J

2014-06-01

Interest in insect glutathione s-transferases (GSTs) has primarily focused on their role in insecticide resistance. These play an important role in biotransformation and detoxification of many different xenobiotic and endogenous substances including insecticides. The GST activity among 10 laboratory selected insecticide resistant and susceptible/control strains of Anopheles stephensi was compared using the substrates 1-chloro-2,4-dinitrobenzene (CDNB). The difference in the GST activities of different life stages of diverse insecticide resistant strains was compared and presented. About 100 larvae, pupae, adult males, adult females and eggs (100 μg in total weight) were collected and used for the experiment. The extracts were prepared from each of the insecticide-resistant strains and control. Protein contents of the enzyme homogenate and GST activities were determined. Deltamethrin and cyfluthrin-resistant strains of An. stephensi showed significantly higher GST activity. Larvae and pupae of DDT-resistant strain showed peak GST activity followed by the propoxur-resistant strain. On contrary, the GST activity was found in reduced quantity in alphamethrin, bifenthrin, carbofuran and chloropyrifos resistant strains. Adults of either sexes showed higher GST activity in mosquito strain resistant to organophosphate group of insecticides namely, temephos and chloropyrifos. The GST activity was closely associated with almost all of the insecticides used in the study, strengthening the fact that one of the mechanisms associated with resistance includes an increase of GST activity. This comparative data on GST activity in An. stephensi can be useful database to identify possible underlying mechanisms governing insecticide-resistance by GSTs.

Glutathione S-transferase P1 Ile105Val Polymorphism and Male Infertility Risk: An Updated Meta-analysis

PubMed Central

Huang, Xue-Kun; Huang, Yong-Han; Huang, Juan-Hua; Liang, Jing-Yao

2017-01-01

Background: Several studies concerning the association between glutathione S-transferase P1 (GSTP1) Ile105Val polymorphism and male infertility risk have reported controversial findings. The present study was aimed to explore this association using a meta-analysis. Methods: The PubMed, EMBASE, China National Knowledge Infrastructure (CNKI), and Wanfang databases were searched. Odds ratios (ORs) with 95% confidence intervals (CIs) were calculated to estimate the strength of the association. Results: A total of 3282 cases and 3268 controls in nine case-control studies were included. There was no significant association between GSTP1 Ile105Val polymorphism and male infertility in the overall population, but significant associations were found under the dominant (OR = 1.23, 95% CI = 1.04–1.46, I2 = 32.2%) and heterozygote (OR = 1.29, 95% CI = 1.08–1.53, I2 = 26.8%) models after excluding studies for which the data did not satisfy Hardy-Weinberg equilibrium (HWE). Similarly, subgroup analyses revealed no significant association in Asians or Chinese population although a significant association was apparent among Chinese population in studies with HWE under the heterozygote model (OR = 1.25, 95% CI = 1.03–1.52, I2 = 44.1%). Significant heterogeneity could be observed in some genetic models, but this heterogeneity was not significant when stratified by HWE. No evidence for publication bias was found. Conclusions: The GSTP1 Ile105Val polymorphism might not be associated with male infertility risk, and thus additional well-designed studies with larger sample size are warranted. PMID:28397729

The effects of endosulfan on cytochrome P450 enzymes and glutathione S-transferases in zebrafish (Danio rerio) livers.

PubMed

Dong, Miao; Zhu, Lusheng; Shao, Bo; Zhu, Shaoyuan; Wang, Jun; Xie, Hui; Wang, Jinhua; Wang, Fenghua

2013-06-01

Endosulfan, an organochlorine pesticide, has been used worldwide in the past decades. The present study was performed to investigate the effect of endosulfan on liver microsomal cytochrome P450 (CYP) enzymes and glutathione S-transferases (GST) in zebrafish. Male and female zebrafish were separated and exposed to a control and four concentrations of endosulfan (0.01, 0.1, 1, and 10μgL(-1)) and were sampled on days 7, 14, 21, and 28. After exposure to endosulfan, the content of CYP increased and later gradually fell back to control level in most sampling time intervals. A similar tendency was also found in the activities of NADPH-P450 reductase (NCR), aminopyrine N-demethylase (APND) and erythromycin N-demethylase (ERND). GST activities were generally higher in treatment groups than control groups. Regarding sex-based differences, the induction degree of the activity of NCR was generally higher in males than females. Similar differences were also found on the 28th day in the activities of APND and ERND, as well as GST activity on the 7th day. Overall, the present results demonstrate the toxicity at low doses of endosulfan and indicated marked induction of CYP and GST enzymes in zebrafish liver. Copyright © 2012 Elsevier Inc. All rights reserved.

Influence of ethacrynic acid on glutathione S-transferase pi transcript and protein half-lives in human colon cancer cells.

PubMed

Shen, H; Ranganathan, S; Kuzmich, S; Tew, K D

1995-10-12

Ethacrynic acid (EA) is a plant phenolic acid that is both an inhibitor and an inducer of glutathione S-transferase (GST) activity. To determine contributory factors in the increased GST activity caused by EA treatment, human colon carcinoma HT29 cells were compared with a cloned EA-resistant population (HT6-8) maintained in medium containing 72 microM EA. Several factors are involved in the increased expression of GST pi in HT6-8. For example, nuclear run-on experiments showed an approximately 2-fold increase in the rate of transcription of GST pi. In addition, the half-life of GST pi transcript was increased from 4.1 (wild type, HT29, HT4-1) to 8.4 hr. The half-life of GST pi protein was 1-2 hr in HT4-1 cells versus 8-9 hr in HT6-8 cells. When either human ovarian carcinoma cells (SKOV3) or human prostatic carcinoma cells (DU145) were treated with EA, the half-life of the GST pi transcript was also increased. The transcript half-lives of another thiol-metabolism enzyme, gamma-glutamylcysteine synthetase (gamma-GCS), and a phase II detoxification enzyme, dihydrodiol dehydrogenase (DDH), were also increased in HT6-8, SKOV3 and DU145 cells treated with EA. However, the half-lives of transcripts from "housekeeping genes," such as glyceraldehyde 3-phosphate dehydrogenase (G3PDH), beta-actin and beta-tubulin, were not changed in these cell lines following EA. Apparently, a number of coordinated factors are involved in EA-enhanced expression of GST pi and other detoxification enzymes.

The structure of a zeta class glutathione S-transferase from Arabidopsis thaliana: characterisation of a GST with novel active-site architecture and a putative role in tyrosine catabolism.

PubMed

Thom, R; Dixon, D P; Edwards, R; Cole, D J; Lapthorn, A J

2001-05-18

The cis-trans isomerisation of maleylacetoacetate to fumarylacetoacetate is the penultimate step in the tyrosine/phenylalanine catabolic pathway and has recently been shown to be catalysed by glutathione S-transferase enzymes belonging to the zeta class. Given this primary metabolic role it is unsurprising that zeta class glutathione S-transferases are well conserved over a considerable period of evolution, being found in vertebrates, plants, insects and fungi. The structure of this glutathione S-transferase, cloned from Arabidopsis thaliana, has been solved by single isomorphous replacement with anomalous scattering and refined to a final crystallographic R-factor of 19.6% using data from 25.0 A to 1.65 A. The zeta class enzyme adopts the canonical glutathione S-transferase fold and forms a homodimer with each subunit consisting of 221 residues. In agreement with structures of glutathione S-transferases from the theta and phi classes, a serine residue (Ser17) is present in the active site, at a position that would allow it to stabilise the thiolate anion of glutathione. Site-directed mutagenesis of this residue confirms its importance in catalysis. In addition, the role of a highly conserved cysteine residue (Cys19) present in the active site of the zeta class glutathione S-transferase enzymes is discussed. Copyright 2001 Academic Press.

Enzymatic Activity of Glutathione S-Transferase and Dental Fluorosis Among Children Receiving Two Different Levels of Naturally Fluoridated Water.

PubMed

Bonola-Gallardo, Irvin; Irigoyen-Camacho, María Esther; Vera-Robles, Liliana; Campero, Antonio; Gómez-Quiroz, Luis

2017-03-01

This study was conducted to measure the activity of the enzyme glutathione S-transferase (GST) in saliva and to compare the activity of this enzyme in children with and without dental fluorosis in communities with different concentrations of naturally fluoridated water. A total of 141 schoolchildren participated in this cross-sectional study. Children were selected from two communities: one with a low (0.4 ppm) and the other with a high (1.8 ppm) water fluoride concentration. Dental fluorosis was evaluated by applying the Thylstrup and Fejerskov Index (TFI) criteria. Stimulated saliva was obtained, and fluoride concentration and GST activity were measured. The GST activity was compared among children with different levels of dental fluorosis using multinomial logistic regression models and odds ratios (OR). The mean age of the children was 10.6 (±1.03) years. Approximately half of the children showed dental fluorosis (52.5 %). The average GST activity was 0.5678 (±0.1959) nmol/min/μg. A higher concentration of fluoride in the saliva was detected in children with a higher GST activity (p = 0.039). A multinomial logistic regression model used to evaluate the GST activity and the dental fluorosis score identified a strong association between TFI = 2-3 (OR = 15.44, p = 0.007) and TFI ≥ 4 (OR = 55.40, p = 0.026) and the GST activity level, compared with children showing TFI = 0-1, adjusted for age and sex. Schoolchildren with higher levels of dental fluorosis and a higher fluoride concentration in the saliva showed greater GST activity. The increased GST activity most likely was the result of the body's need to inactivate free radicals produced by exposure to fluoride.

Chronically sun-damaged melanomas express low levels of nuclear glutathione-S-transferase-π: an epidemiological and clinicopathological study in Italy.

PubMed

Campione, Elena; Medda, Emanuela; Paternò, Evelin J; Diluvio, Laura; Ricozzi, Ilaria; Carboni, Isabella; Costanza, Gaetana; Rossi, Piero; Rapanotti, Cristina; Di Stefani, Alessandro; Chimenti, Sergio; Bianchi, Luca; Orlandi, Augusto

2015-01-01

The detoxifying enzyme glutathione-s-transferase pi (GST-π) is present in keratinocytes and melanocytes and exerts a protective role against tumour progression. Melanomas close to melanocytic naevus remnants occur less frequently on sun-exposed areas, whereas solar dermal elastosis, hallmark of chronic sun-damage, characterise melanomas on sun-exposed skin. We evaluated the expression of GST-π in 113 melanomas associated to melanocytic naevus remnants or to solar dermal elastosis, classified according to clinical characteristics, history of sun exposure, histological subtypes and AJCC staging. Chronically sun-damaged melanomas, identified by moderate-severe solar dermal elastosis, showed a lower nuclear GST-π expression and a higher thickness than those related to melanocytic naevus remnants (p < 0.03). Multivariate logistic regression analysis demonstrated that male gender and chronic sun-exposure are independent risk factors significantly associated to melanomas localised on the trunk (OR = 3.36, 95% CI: 1.31-8.65; OR = 5.97, 95% CI: 1.71-20.87). If confirmed on a larger series, lower expression of nuclear GST-π in melanoma cells could represent a possible marker of chronically sun-damaged melanoma pathogenesis.

Purification, molecular cloning and heterologous expression of a glutathione S-transferase involved in insecticide resistance from the rice brown planthopper, Nilaparvata lugens.

PubMed

Vontas, John G; Small, Graham J; Nikou, Dimitra C; Ranson, Hilary; Hemingway, Janet

2002-03-01

A novel glutathione S-transferase (GST)-based pyrethroid resistance mechanism was recently identified in Nilaparvata lugens [Vontas, Small and Hemingway (2001) Biochem. J. 357, 65-72]. To determine the nature of GSTs involved in conferring this resistance, the GSTs from resistant and susceptible strains of N. lugens were partially purified by anion exchange and affinity chromatography. The majority of peroxidase activity, previously correlated with resistance, was confined to the fraction that bound to the affinity column, which was considerably elevated in the resistant insects. A cDNA clone encoding a GST (nlgst1-1) - the first reported GST sequence from Hemiptera with up to 54% deduced amino-acid identity with other insect class I GSTs - was isolated from a pyrethroid-resistant strain. Northern analysis showed that nlgst1-1 was overexpressed in resistant insects. nlgst1-1 was expressed in Escherichia coli, purified and characterized. The ability of the recombinant protein to bind to the S-hexylglutathione affinity matrix, its substrate specificities and its immunological properties confirmed that this GST was one from the elevated subset of N. lugens GSTs. Peroxidase activity of the recombinant nlgst1-1 indicated that it had a role in resistance, through detoxification of lipid peroxidation products induced by pyrethroids. Southern analysis of genomic DNA from the resistant and susceptible strains indicated that GST-based insecticide resistance may be associated with gene amplification in N. lugens.

Differences among allelic variants of human glutathione transferase A2-2 in the activation of azathioprine.

PubMed

Zhang, Wei; Modén, Olof; Mannervik, Bengt

2010-07-30

Azathioprine has been clinically used for decades in connection with organ transplantation, autoimmune disease, and treatment of cancer. Toxic side-reactions are common and have been linked to the liberation of excessively high concentrations of 6-mercaptopurine and corresponding toxic metabolites. An allelic variant of thiopurine methyltransferase with low activity is associated with elevated concentrations of 6-mercaptopurine. However, other genetic markers remain to be identified in order to fully account for adverse reactions and efficacy failure. In the present study, we studied the five known allelic variants of human glutathione transferase A2-2 (GST A2-2) (EC 2.5.1.18), abundantly expressed in liver and efficiently catalyzing the bioactivation of azathioprine to release 6-mercaptopurine. All five variants exhibited high activity with azathioprine, but allelic variant E of GST A2-2 displayed a 3-4-fold elevated catalytic efficiency compared to the other variants. High GST activity can lead to overproduction of 6-mercaptopurine, and the nature of the multiple forms of GSTs in a patient will obviously affect the metabolism of azathioprine. In addition to GST A2-2, the polymorphic GST M1-1 is also highly active with azathioprine. Considering our findings, it appears that the genotypic and phenotypic variations in the GST complement may influence the presentation of adverse reactions in patients treated with azathioprine. Clinical trials will be required to clarify the impact of the GST expression in comparison with the established biomarker thiopurine methyltransferase as predictors of adverse reactions. (c) 2010 Elsevier Ireland Ltd. All rights reserved.

Clinicopathological correlates and prognostic significance of glutathione S-transferase Pi expression in 468 patients after potentially curative resection of node-positive colonic cancer.

PubMed

Tan, King L; Jankova, Lucy; Chan, Charles; Fung, Caroline L-S; Clarke, Candice; Lin, Betty P C; Robertson, Graham; Molloy, Mark; Chapuis, Pierre H; Bokey, Les; Dent, Owen F; Clarke, Stephen J

2011-12-01

This study investigated the association between glutathione S-transferase Pi (GST Pi) expression, histopathology and overall survival in 468 patients after resection of stage C colonic adenocarcinoma. Data were drawn from a prospective hospital registry of consecutive bowel cancer resections with a minimum follow-up of 5 years. Nuclear and cytoplasmic GST Pi expression, assessed by both intensity of staining and percentage of stained cells at both the central part of the tumour and the invasive tumour front, were evaluated retrospectively by tissue microarray immunohistochemistry on archival specimens. The most effective measure of GST Pi expression was the percentage of immunostained nuclei in central tumour tissue, where >40% stained was associated significantly with high grade, invasion beyond the muscularis propria, involvement of a free serosal surface or apical node, and invasion into an adjacent organ or structure. After adjustment of other predictors, GST Pi expression remained independently prognostic for reduced overall survival (hazard ratio 1.4, P = 0.002). In patients with clinicopathological stage C colonic cancer, GST Pi expression is associated with features of tumour aggressiveness and with reduced overall survival. Further appropriately designed studies should aim to discover whether GST Pi can predict response to adjuvant chemotherapy. © 2011 Blackwell Publishing Limited.

Inhibition of P-glycoprotein and glutathione S-transferase-pi mediated resistance by fluoxetine in MCF-7/ADM cells.

PubMed

Zhang, Ye; Zhou, Ting; Duan, Jingjing; Xiao, Zhijun; Li, Guihua; Xu, Feng

2013-10-01

Chemotherapy is important in the systematic treatment of breast cancer. While multidrug resistance (MDR) is the main obstacle in chemotherapy, a reversal reagent with high reversal effect but low toxicity is the hotspot issue at present to overcome MDR. Antidepressant fluoxetine (FLX) is a potential new highly effective chemosensitizer, however, the possible mechanism is unclear. In this study, the effect of FLX on multidrug resistance mediated by P-glycoprotein (P-gp) and glutathione S-transferase-pi (GST-π) were researched in resistant/sensitive breast cancer cells. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) was used to determine the cells viability after being incubated with FLX/Adriamycin (ADM)/Paclitaxel (PTX) alone or FLX-ADM, FLX-PTX combination. Western blot was performed to assay the expression of P-gp and GST-π proteins. Reverse transcriptase polymerase chain reaction (RT-PCR) and quantitative real-time PCR (qRT-PCR) were performed to assay the level of MDR1 mRNA. The results showed that pre-treatment with FLX enhance cytotoxicity significantly both on resistant and sensitive cells, downregulated the expression of P-gp and GST-π proteins in resistance cells, decreased the MDR1 mRNA by FLX-PTX combination only. No P-gp and GST-π were detected in sensitive cells. Our research thus indicated that FLX reverse the breast cancer cell's resistance and enhance the chemosensitivity by regulating P-gp and GST-π levels. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

Three-dimensional structure of Schistosoma japonicum glutathione S-transferase fused with a six-amino acid conserved neutralizing epitope of gp41 from HIV

NASA Technical Reports Server (NTRS)

Lim, Kap; Ho, Joseph X.; Keeling, Kim; Gilliland, Gary L.; Ji, Xinhua; Rueker, Florian; Carter, Daniel C.

1994-01-01

The 3-dimensional crystal structure of glutathione S-transferase (GST) of Schistosoma japonicum (Sj) fused with a conserved neutralizing epitope on gp41 (glycoprotein, 41 kDa) of human immunodeficiency virus type 1 (HIV-1) was determined at 2.5 A resolution. The structure of the 3-3 isozyme rat GST of the mu gene class was used as a molecular replacement model. The structure consists of a 4-stranded beta-sheet and 3 alpha-helices in domain 1 and 5 alpha-helices in domain 2. The space group of the Sj GST crystal is P4(sub 3)2(sub 1)2 with unit cell dimensions of a = b = 94.7 A, and c = 58.1 A. The crystal has 1 GST monomer per asymmetric unit, and 2 monomers that form an active dimer are related by crystallographic 2-fold symmetry. In the binding site, the ordered structure of reduced glutathione is observed. The gp41 peptide (Glu-Leu-Asp-Lys-Trp-Ala) fused to the C-terminus of Sj GST forms a loop stabilized by symmetry-related GSTs. The Sj GST structure is compared with previously determined GST structures of mammalian gene classes mu, alpha, and pi. Conserved amino acid residues among the 4 GSTs that are important for hydrophobic and hydrophilic interactions for dimer association and glutathione binding are discussed.

Novel role for glutathione S-transferase pi. Regulator of protein S-Glutathionylation following oxidative and nitrosative stress.

PubMed

Townsend, Danyelle M; Manevich, Yefim; He, Lin; Hutchens, Steven; Pazoles, Christopher J; Tew, Kenneth D

2009-01-02

Glutathione S-transferase Pi (GSTpi) is a marker protein in many cancers and high levels are linked to drug resistance, even when the selecting drug is not a substrate. S-Glutathionylation of proteins is critical to cellular stress response, but characteristics of the forward reaction are not known. Our results show that GSTpi potentiates S-glutathionylation reactions following oxidative and nitrosative stress in vitro and in vivo. Mutational analysis indicated that the catalytic activity of GST is required. GSTpi is itself redox-regulated. S-Glutathionylation on Cys47 and Cys101 autoregulates GSTpi, breaks ligand binding interactions with c-Jun NH2-terminal kinase (JNK), and causes GSTpi multimer formation, all critical to stress response. Catalysis of S-glutathionylation at low pK cysteines in proteins is a novel property for GSTpi and may be a cause for its abundance in tumors and cells resistant to a range of mechanistically unrelated anticancer drugs.

Expression of glutathione S-transferases in poplar trees (Populus trichocarpa) exposed to 2,4,6-trinitrotoluene (TNT).

PubMed

Brentner, Laura B; Mukherji, Sachiyo T; Merchie, Kate M; Yoon, Jong Moon; Schnoor, Jerald L; Van Aken, Benoit

2008-10-01

Twelve Populus genes were identified from Arabidopsis thaliana sequences previously shown to be induced by exposure to 2,4,6-trinitrotoluene (TNT). Using the resources of the Poplar Genome Project and National Center for Biotechnology Information databases, Populus conserved domains were identified and used to design gene specific primers. RNA extracted from root tissues of TNT-exposed hydroponic poplar plants was used to quantify the expression of genes by reverse-transcriptase real-time polymerase chain reaction. Cyclophilin and 18S ribosomal DNA genes were used as internal standards. Exposure to TNT resulted in a significant increase of gene expression of two glutathione S-transferases (GST), peaking at levels of 25.0 +/- 13.1 and 10 +/- 0.7 fold the expression level of non-exposed plants after 24 h for each of the GST genes, respectively. This paper demonstrates the use of functional genomics information from the model plant species, Arabidopsis, to identify genes which may be important in detoxification of TNT in the model phytoremediation species, Populus trichocarpa.

Immunoreactivities for glutathione S-transferases and glutathione peroxidase in the lateral wall of pigmented and albino guinea pig cochlea.

PubMed

Fujimura, Takeyuki; Suzuki, Hideaki; Udaka, Tsuyoshi; Shiomori, Teruo; Mori, Takanori; Inaba, Tsuyoshi; Hiraki, Nobuaki; Kayashima, Kotaro; Doi, Yoshiaki

2008-09-01

Dark-skinned people are known to be more tolerant of ototraumatic noise than are light-skinned people, and pigmented animals are more tolerant of ototraumatic noise and aminoglycoside ototoxicity than are albino animals. Such tolerance may be dependent on the local ability of detoxification and antioxidant enzymes, including glutathione S-transferase (GST) and glutathione peroxidase (GSPx). In the present study, we examined the difference in GST/GSPx expression in the lateral wall of the cochlea between pigmented and albino guinea pigs. Eight-week-old male pigmented and albino guinea pigs were killed by transcardiac perfusion with 2% paraformaldehyde. The cochlear ducts were isolated, further fixed with 4% paraformaldehyde, decalcified, and then embedded in paraffin. Sections prepared at 5-microm thickness were incubated with anti-GST-alpha,-mu,-pi, or anti-GSPx antibody, reacted with Alexa Fluorconjugated secondary antibody, and examined under a Carl Zeiss Axioskop 2 plus fluorescence microscope. The cochlea ducts were also subjected to immunoelectron microscopy for GST-pi by the postembedment method. The stria vascularis of pigmented guinea pigs was strongly immunoreactive for GST-alpha,-mu,-pi, and GSPx, whereas no or only weak immunoreactivities were seen in the stria vascularis of albino guinea pigs. The spiral ligament showed positive but different immunoreactivities for these enzymes between the strains. Double-stained immunofluorescence micrographs for GST-pi and GSPx showed a close resemblance of localization between the two enzymes in both pigmented and albino guinea pigs. At the ultrastructural level, immunoreactivity for GST-pi was localized preferentially in the melanin cells of pigmented guinea pigs. These results suggest that correlation between pigmentation and inner ear susceptibility is, at least partially, attributed to the different distribution of GST/GSPx in the stria vascularis.

Cooperativity and pseudo-cooperativity in the glutathione S-transferase from Plasmodium falciparum.

PubMed

Liebau, Eva; De Maria, Francesca; Burmeister, Cora; Perbandt, Markus; Turella, Paola; Antonini, Giovanni; Federici, Giorgio; Giansanti, Francesco; Stella, Lorenzo; Lo Bello, Mario; Caccuri, Anna Maria; Ricci, Giorgio

2005-07-15

Binding and catalytic properties of glutathione S-transferase from Plasmodium falciparum (PfGST) have been studied by means of fluorescence, steady state and pre-steady state kinetic experiments, and docking simulations. This enzyme displays a peculiar reversible low-high affinity transition, never observed in other GSTs, which involves the G-site and shifts the apparent K(D) for glutathione (GSH) from 200 to 0.18 mM. The transition toward the high affinity conformation is triggered by the simultaneous binding of two GSH molecules to the dimeric enzyme, and it is manifested as an uncorrected homotropic behavior, termed "pseudo-cooperativity." The high affinity enzyme is able to activate GSH, lowering its pK(a) value from 9.0 to 7.0, a behavior similar to that found in all known GSTs. Using 7-chloro-4-nitrobenzo-2-oxa-1,3-diazole, this enzyme reveals a potential optimized mechanism for the GSH conjugation but a low catalytic efficiency mainly due to a very low affinity for this co-substrate. Conversely, PfGST efficiently binds one molecule of hemin/monomer. The binding is highly cooperative (n(H) = 1.8) and occurs only when GSH is bound to the enzyme. The thiolate of GSH plays a crucial role in the intersubunit communication because no cooperativity is observed when S-methylglutathione replaces GSH. Docking simulations suggest that hemin binds to a pocket leaning into both the G-site and the H-site. The iron is coordinated by the amidic nitrogen of Asn-115, and the two carboxylate groups are in electrostatic interaction with the epsilon-amino group of Lys-15. Kinetic and structural data suggest that PfGST evolved by optimizing its binding property with the parasitotoxic hemin rather than its catalytic efficiency toward toxic electrophilic compounds.

Evaluation of the in vitro inhibitory impact of hypericin on placental glutathione S-transferase pi.

PubMed

Dalmizrak, Ozlem; Kulaksiz-Erkmen, Gulnihal; Ozer, Nazmi

2012-10-01

St John's Wort (SJW) extracts are herbal products which are available without prescription in most countries and widely used in the treatment of mild to moderate depression. Since it is a herbal product and available without prescription, use of SJW is common among pregnant and/or lactating woman. The principal of the study was to clarify the effects of hypericin, one of the components of SJW, on glutathione S-transferase-pi (GST-pi) purified from human placenta. The K (m) values of GST-pi were 0.21 ± 0.03 mM for glutathione (GSH) and 2.29 ± 0.54 mM for 1-chloro-2,4-dinitrobenzene (CDNB). At fixed [GSH], the V (m) value calculated was about 3 times higher than the conditions in which [CDNB] was fixed; 201 ± 30 U/mg protein versus 74 ± 3 U/mg protein. At constant substrate concentrations (1 mM), an average IC (50) value of 0.70 ± 0.02 μM was obtained. Hypericin inhibited GST-pi competitively with respect to both substrates. When GSH was the varied substrate a K (i) value of 0.31 ± 0.05 μM was found; when CDNB was the varied substrate, a K (i) value of 0.85 ± 0.02 μM was obtained. On the basis of these data considering transplacental transfer of hypericin and immature hepatic clearance of the baby, using this herbal product may cause abnormalites due to the inhibition of one of the most important placental detoxification enzymes, GST-pi.

Genomic Insights into the Glutathione S-Transferase Gene Family of Two Rice Planthoppers, Nilaparvata lugens (Stål) and Sogatella furcifera (Horváth) (Hemiptera: Delphacidae)

PubMed Central

Zhou, Wen-Wu; Liang, Qing-Mei; Xu, Yi; Gurr, Geoff M.; Bao, Yan-Yuan; Zhou, Xue-Ping; Zhang, Chuan-Xi; Cheng, Jiaan; Zhu, Zeng-Rong

2013-01-01

Background Glutathione S-transferase (GST) genes control crucial traits for the metabolism of various toxins encountered by insects in host plants and the wider environment, including insecticides. The planthoppers Nilaparvata lugens and Sogatella furcifera are serious specialist pests of rice throughout eastern Asia. Their capacity to rapidly adapt to resistant rice varieties and to develop resistance to various insecticides has led to severe outbreaks over the last decade. Methodology/Principal Findings Using the genome sequence of N. lugens, we identified for the first time the complete GST gene family of a delphacid insect whilst nine GST gene orthologs were identified from the closely related species S. furcifera. Nilaparvata lugens has 11 GST genes belonging to six cytosolic subclasses and a microsomal class, many fewer than seen in other insects with known genomes. Sigma is the largest GST subclass, and the intron–exon pattern deviates significantly from that of other species. Higher GST gene expression in the N. lugens adult migratory form reflects the higher risk of this life stage in encountering the toxins of non-host plants. After exposure to a sub-lethal dose of four insecticides, chlorpyrifos, imidacloprid, buprofezin or beta-cypermethrin, more GST genes were upregulated in S. furcifera than in N. lugens. RNA interference targeting two N. lugens GST genes, NlGSTe1 and NlGSTm2, significantly increased the sensitivity of fourth instar nymphs to chlorpyrifos but not to beta-cypermethrin. Conclusions/Significance This study provides the first elucidation of the nature of the GST gene family in a delphacid species, offering new insights into the evolution of metabolic enzyme genes in insects. Further, the use of RNA interference to identify the GST genes induced by insecticides illustrates likely mechanisms for the tolerance of these insects. PMID:23457591

Genomic insights into the glutathione S-transferase gene family of two rice planthoppers, Nilaparvata lugens (Stål) and Sogatella furcifera (Horváth) (Hemiptera: Delphacidae).

PubMed

Zhou, Wen-Wu; Liang, Qing-Mei; Xu, Yi; Gurr, Geoff M; Bao, Yan-Yuan; Zhou, Xue-Ping; Zhang, Chuan-Xi; Cheng, Jiaan; Zhu, Zeng-Rong

2013-01-01

Glutathione S-transferase (GST) genes control crucial traits for the metabolism of various toxins encountered by insects in host plants and the wider environment, including insecticides. The planthoppers Nilaparvata lugens and Sogatella furcifera are serious specialist pests of rice throughout eastern Asia. Their capacity to rapidly adapt to resistant rice varieties and to develop resistance to various insecticides has led to severe outbreaks over the last decade. Using the genome sequence of N. lugens, we identified for the first time the complete GST gene family of a delphacid insect whilst nine GST gene orthologs were identified from the closely related species S. furcifera. Nilaparvata lugens has 11 GST genes belonging to six cytosolic subclasses and a microsomal class, many fewer than seen in other insects with known genomes. Sigma is the largest GST subclass, and the intron-exon pattern deviates significantly from that of other species. Higher GST gene expression in the N. lugens adult migratory form reflects the higher risk of this life stage in encountering the toxins of non-host plants. After exposure to a sub-lethal dose of four insecticides, chlorpyrifos, imidacloprid, buprofezin or beta-cypermethrin, more GST genes were upregulated in S. furcifera than in N. lugens. RNA interference targeting two N. lugens GST genes, NlGSTe1 and NlGSTm2, significantly increased the sensitivity of fourth instar nymphs to chlorpyrifos but not to beta-cypermethrin. This study provides the first elucidation of the nature of the GST gene family in a delphacid species, offering new insights into the evolution of metabolic enzyme genes in insects. Further, the use of RNA interference to identify the GST genes induced by insecticides illustrates likely mechanisms for the tolerance of these insects.

In vitro kinetics of hepatic glutathione s-transferase conjugation in largemouth bass and brown bullheads

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gallagher, E.P.; Sheehy, K.M.; Lame, M.W.

2000-02-01

The kinetics of glutathione 5-transferase (GST) catalysis were investigated in largemouth bass (Micropterus salmoides) and brown bullheads (Amerius nebulosus), two freshwater fish species found in a variety of polluted waterways in the eastern US. The initial rates of hepatic GST activity toward four GST substrates, including 1-chloro-2,4-dinitrobenzene, ethacrynic acid, {Delta}5-androstene-17-dione, and nitrobutyl chloride, were significantly higher in brown bullheads than in largemouth bass. Hepatic GST activity toward 1,2-dichloro-4-nitrobenzene, a {mu}-class GST substrate in rodents, was not detectable in either species. Liver cytosolic GSTs were more efficient in bullheads than in bass at catalyzing 1-chloro-2,4-dinitrobenzene-reduced glutathione (CDNB-GSH) conjugation over a broadmore » range of electrophile (CDNB) concentrations, including those representative of environmental exposure. In contrast, largemouth bass maintained higher ambient concentrations of GSH, the nucleophilic cofactor for GST-mediated conjugation, than brown bullheads. Biphasic kinetics for GST-CDNB conjugation under conditions of variable GSH concentration were apparent in Eadie-Hofstee plots of the kinetic data, suggesting the presence of at least two hepatic GST isozymes with markedly different K{sub m} values for GSH in both species. The GST-CDNB reaction rate data obtained under conditions of variable GSH were well fitted (R{sup 2} = 0.999) by the two-enzyme Michaelis-Menten equation. In addition, Western blotting experiments confirmed the presence of two different hepatic GST-like proteins in both largemouth bass and brown bullhead liver. Collectively, these findings indicate that largemouth bass and brown bullhead GSTs catalyze the conjugation of structurally diverse, class-specific GST substrates, and that brown bullheads exhibit higher initial rates of GST activity than largemouth bass. The relatively higher rates of in vitro liver GST activity at the low substrate

Echinococcus granulosus: Evidence of a heterodimeric glutathione transferase built up by phylogenetically distant subunits.

PubMed

Arbildi, Paula; La-Rocca, Silvana; Lopez, Veronica; Da-Costa, Natalia; Fernandez, Veronica

2017-01-01

In the cestode parasite Echinococcus granulosus, three phylogenetically distant cytosolic glutathione transferases (GSTs) (EgGST1, 2 and 3) were identified. Interestingly, the C-terminal domains of EgGST3 and EgGST2 but not EgGST1, exhibit all amino acids involved in Sigma-class GST dimerization. Here, we provide evidence indicating that EgGST2 and EgGST3 naturally form a heterodimeric structure (EgGST2-3), and also we report the enzymatic activity of the recombinant heterodimer. EgGST2-3 might display novel properties able to influence the infection establishment. This is the first report of a stable heterodimeric GST built up by phylogenetically distant subunits. Copyright © 2016 Elsevier B.V. All rights reserved.

Human cytosolic glutathione-S-transferases: quantitative analysis of expression, comparative analysis of structures and inhibition strategies of isozymes involved in drug resistance.

PubMed

Mohana, Krishnamoorthy; Achary, Anant

2017-08-01

Glutathione-S-transferase (GST) inhibition is a strategy to overcome drug resistance. Several isoforms of human GSTs are present and they are expressed in almost all the organs. Specific expression levels of GSTs in various organs are collected from the human transcriptome data and analysis of the organ-specific expression of GST isoforms is carried out. The variations in the level of expressions of GST isoforms are statistically significant. The GST expression differs in diseased conditions as reported by many investigators and some of the isoforms of GSTs are disease markers or drug targets. Structure analysis of various isoforms is carried out and literature mining has been performed to identify the differences in the active sites of the GSTs. The xenobiotic binding H site is classified into H1, H2, and H3 and the differences in the amino acid composition, the hydrophobicity and other structural features of H site of GSTs are discussed. The existing inhibition strategies are compared. The advent of rational drug design, mechanism-based inhibition strategies, availability of high-throughput screening, target specific, and selective inhibition of GST isoforms involved in drug resistance could be achieved for the reversal of drug resistance and aid in the treatment of diseases.

A study on effects of glutathione s-transferase from silkworm on CCL4-induced mouse liver injury.

PubMed

Yan, Hui; Gui, Zhongzheng; Wang, Bochu

2011-01-01

To assess the hepatoprotective activity of Glutathione S-transferase(GSTsw), extracted and purified from silkworm, in experimental acute mice liver injury and explore mechanisms. Mice were divided into five groups: control group, carbon tetrachloride (CCl4) group, and three treatment groups that received CCl4 and GSTsw at doses of 0.083 mg•g(-1), 0.0415 mg•g(-1) and 0.0207 mg•g(-1) for 3 days. ALT in serum, GST, SOD and T-AOC in liver tissue homogenate, and changes in liver pathology in the five groups were studied. CCl4 administration led to pathological and biochemical evidence of liver injury as compared to untreated controls. GSTsw administration led to significant protection against CCl4-induced changes in liver pathology. It was also associatedwith significantly lower serum ALT levels, higher GST-SOD and T-AOC level in live tissue homogenate. Thus, GSTsw showed protective activity against CCl4-induced hepatotoxicity in mice.

Effects of GSTM1/GSTT1 gene polymorphism and fruit & vegetable consumption on antioxidant biomarkers and cognitive function in the elderly: a community based cross-sectional study.

PubMed

Yuan, Linhong; Ma, Weiwei; Liu, Jinmeng; Meng, Liping; Liu, Jixia; Li, Shuang; Han, Jing; Liu, Quanri; Feng, Lingli; Wang, Chao; Xiao, Rong

2014-01-01

It was reported that Glutathione S-transferase (GST) gene polymorphism and fruit and vegetable (FV) intake were associated with body antioxidant capacity. The oxidative/anti-oxidative imbalance played an important role in the pathogenesis of AD. However, the association of GST genotype, dietary FV consumption with body antioxidant biomarkers and cognitive function in the elderly is not clear. The aim of the present study was to determine the association of GST genotype, and dietary FV intake, with antioxidant biomarkers and cognitive function in the elderly. Food frequency questionnaire was used to collect data of dietary FV intakes in 504 community dwelling elderly aged from 55 to 75 years old. GSTM1 and GSTT1 genotypes were determined by using multiple-PCR method. Plasma and erythrocyte antioxidant biomarkers were measured. Cognitive function was measured by using Montreal Cognitive Assessment. Statistical analysis was applied for exploring the association of GST genotype and FV intake with antioxidant biomarkers level and cognitive function in the elderly. Individual GSTM1 or GSTT1 gene deletion affects body antioxidant biomarkers levels, including erythrocyte GST activity, plasma total antioxidant capacity, and glutathione levels. GSTM1and/or GSTT1 gene deletion have no effects on cognitive function in the surveyed participants. The effect of GST genotype on antioxidant biomarkers are FV intake dependent. There is interaction of FV intake and GST genotype on cognitive function in the elderly. GST genotype or daily FV consumption impact body antioxidant biomarkers, but not cognitive function in the elderly. There were combined effects of GST genotype and FV consumption on cognitive function in the elderly population. Large scale perspective population study is required to explore the association of GST genetic polymorphism, FV consumption and antioxidant biomarkers and cognitive function in the elderly.

Anti-CD25 monoclonal antibody enhances the protective efficacy of Schistosoma japonicum GST vaccine via inhibition of CD4+CD25+Foxp3+ regulatory T cells.

PubMed

Tang, Chun-Lian; Yang, Jin; Cheng, Liang-Yu; Cheng, Lan-Fang; Liu, Zhi-Ming

2017-10-01

The effect of anti-CD25 monoclonal antibody (anti-CD25 mAb) on the protection efficacy of Schistosoma japonicum 26 kDa GST (glutathione-S-transferase) vaccine was evaluated. Mice were immunized with GST before infection with S. japonicum cercariae and then injected with anti-CD25 mAb. The worm reduction rate was promoted from 24.18% in mice with GST immunization to 47.09% in mice with GST plus anti-CD25 mAb. Compared with the control group, the percentages of splenic CD4 + CD25 + Foxp3 + regulatory T cells (Tregs) were significantly lower after administration of anti-CD25 mAb; meanwhile, elevated levels of IFN-γ and IL-2 were secreted by splenocytes. These results indicate that the poor protective efficacy of the GST vaccine against S. japonicum results from the presence of CD4 + CD25 + Foxp3 + Tregs, while anti-CD25 mAb can partially block CD4 + CD25 + Foxp3 + Tregs and thus enhance the protective efficacy of the GST vaccine.

Identification and characterisation of multiple glutathione S-transferase genes from the diamondback moth, Plutella xylostella.

PubMed

Chen, Xi'en; Zhang, Ya-lin

2015-04-01

The diamondback moth (DBM), Plutella xylostella, is one of the most harmful insect pests on crucifer crops worldwide. In this study, 19 cDNAs encoding glutathione S-transferases (GSTs) were identified from the genomic and transcriptomic database for DBM (KONAGAbase) and further characterized. Phylogenetic analysis showed that the 19 GSTs were classified into six different cytosolic classes, including four in delta, six in epsilon, three in omega, two in sigma, one in theta and one in zeta. Two GSTs were unclassified. RT-PCR analysis revealed that most GST genes were expressed in all developmental stages, with higher expression in the larval stages. Six DBM GSTs were expressed at the highest levels in the midgut tissue. Twelve purified recombinant GSTs showed varied enzymatic properties towards 1-chloro-2,4-dinitrobenzene and glutathione, whereas rPxGSTo2, rPxGSTz1 and rPxGSTu2 had no activity. Real-time quantitative PCR revealed that expression levels of the 19 DBM GST genes were varied and changed after exposure to acephate, indoxacarb, beta-cypermethrin and spinosad. PxGSTd3 was significantly overexpressed, while PxGSTe3 and PxGSTs2 were significantly downregulated by all four insecticide exposures. The changes in DBM GST gene expression levels exposed to different insecticides indicate that they may play individual roles in tolerance to insecticides and xenobiotics. © 2014 Society of Chemical Industry.

Interaction of Ferulic Acid with Glutathione S-Transferase and Carboxylesterase Genes in the Brown Planthopper, Nilaparvata lugens.

PubMed

Yang, Jun; Sun, Xiao-Qin; Yan, Shu-Ying; Pan, Wen-Jun; Zhang, Mao-Xin; Cai, Qing-Nian

2017-07-01

Plant phenolics are crucial defense phytochemicals against herbivores and glutathione S-transferase (GST) and carboxylesterase (CarE) in herbivorous insects are well-known detoxification enzymes for such xenobiotics. To understand relationship between a plant phenolic and herbivore GST or CarE genes, we evaluated the relationship between a rice phenolic ferulic acid and resistance to brown planthopper (BPH, Nilaparvata lugens), and investigated the interaction of ferulic acid with GST or CarE genes in BPH. The results indicate that ferulic acid content in tested rice varieties was highly associated with resistance to BPH. Bioassays using artificial diets show that the phenolic acid toxicity to BPH was dose dependent and the LC 25 and LC 50 were 5.81 and 23.30 μg/ml at 72 hr, respectively. Activities of the enzymes BPH GST and CarE were increased at concentrations below the LC 50 of ferulic acid. Moreover, low ferulic acid concentrations (< LC 25 ) upregulated the transcriptional levels of NlGSTD1 and NlGSTE1 of the GST family and NlCE of the CarE family. By using dsRNA-induced gene silencing (DIGS) of GST or CarE, it was shown that suppressed expression levels of NlGSTD1, NlGSTE1 and NlCE were 14.6%-21.2%, 27.8%-34.2%, and 10.5%-19.8%, respectively. Combination of NlGSTD1, NlGSTE1 or NlCE knockdown with ferulic acid increased nymph mortality by 92.9%, 119.9%, or 124.6%, respectively. These results suggest that depletion of detoxification genes in herbivorous insects by plant-mediated RNAi technology might be a new potential resource for improving rice resistance to BPH.

Comprehensive genome-wide analysis of Glutathione S-transferase gene family in potato (Solanum tuberosum L.) and their expression profiling in various anatomical tissues and perturbation conditions.

PubMed

Islam, Md Shiful; Choudhury, Mouraj; Majlish, Al-Nahian Khan; Islam, Tahmina; Ghosh, Ajit

2018-01-10

Glutathione S-transferases (GSTs) are ubiquitous enzymes which play versatile functions including cellular detoxification and stress tolerance. In this study, a comprehensive genome-wide identification of GST gene family was carried out in potato (Solanum tuberosum L.). The result demonstrated the presence of at least 90 GST genes in potato which is greater than any other reported species. According to the phylogenetic analyses of Arabidopsis, rice and potato GST members, GSTs could be subdivided into ten different classes and each class is found to be highly conserved. The largest class of potato GST family is tau with 66 members, followed by phi and lambda. The chromosomal localization analysis revealed the highly uneven distribution of StGST genes across the potato genome. Transcript profiling of 55 StGST genes showed the tissue-specific expression for most of the members. Moreover, expression of StGST genes were mainly repressed in response to abiotic stresses, while largely induced in response to biotic and hormonal elicitations. Further analysis of StGST gene's promoter identified the presence of various stress responsive cis-regulatory elements. Moreover, one of the highly stress responsive StGST members, StGSTU46, showed strong affinity towards flurazole with lowest binding energy of -7.6kcal/mol that could be used as antidote to protect crop against herbicides. These findings will facilitate the further functional and evolutionary characterization of GST genes in potato. Copyright © 2017 Elsevier B.V. All rights reserved.

Impact of glutathione S-transferase M1 and T1 on anti-tuberculosis drug-induced hepatotoxicity in Chinese pediatric patients.

PubMed

Liu, Fang; Jiao, An-xia; Wu, Xi-rong; Zhao, Wei; Yin, Qing-qin; Qi, Hui; Jiao, Wei-wei; Xiao, Jing; Sun, Lin; Shen, Chen; Tian, Jian-ling; Shen, Dan; Jacqz-Aigrain, Evelyne; Shen, A-dong

2014-01-01

Anti-tuberculosis drug induced hepatotoxicity (ATDH) is a major adverse drug reaction associated for anti-tuberculosis therapy. The glutathione S-transferases (GST) plays a crucial role in the detoxification of hepatotoxic metabolites of anti-tuberculosis drugs.An association between GSTM1/GSTT1 null mutations and increased risk of ATDH has been demonstrated in adults. Given the ethnic differences and developmental changes, our study aims to investigate the potential impacts of GSTM1/GSTT1 genotypes on the development of ATDH in Han Chinese children treated with anti-tuberculosis therapy. Children receiving anti-tuberculosis therapy with or without evidence of ATDH were considered as the cases or controls, respectively. The GSTM1 and GSTT1 genotyping were performed using the polymerase chain reaction. One hundred sixty-three children (20 cases and 143 controls) with a mean age of 4.7 years (range: 2 months-14.1 years) were included. For the GSTM1, 14 (70.0%) cases and 96 (67.1%) controls had homozygous null mutations. For the GSTT1, 13 (65.0%) cases and 97 (67.8%) controls had homozygous null mutations. Neither the GSTM1, nor the GSTT1 polymorphism was significantly correlated with the occurrence of ATHD. Our results did not support the GSTM1 and GSTT1 polymorphisms as the predictors of ADTH in Chinese Han children treated with anti-tuberculosis drugs. An age-related association between pharmacogenetics and ATHD need to be confirmed in the further study.

Purification, molecular cloning and heterologous expression of a glutathione S-transferase involved in insecticide resistance from the rice brown planthopper, Nilaparvata lugens.

PubMed Central

Vontas, John G; Small, Graham J; Nikou, Dimitra C; Ranson, Hilary; Hemingway, Janet

2002-01-01

A novel glutathione S-transferase (GST)-based pyrethroid resistance mechanism was recently identified in Nilaparvata lugens [Vontas, Small and Hemingway (2001) Biochem. J. 357, 65-72]. To determine the nature of GSTs involved in conferring this resistance, the GSTs from resistant and susceptible strains of N. lugens were partially purified by anion exchange and affinity chromatography. The majority of peroxidase activity, previously correlated with resistance, was confined to the fraction that bound to the affinity column, which was considerably elevated in the resistant insects. A cDNA clone encoding a GST (nlgst1-1) - the first reported GST sequence from Hemiptera with up to 54% deduced amino-acid identity with other insect class I GSTs - was isolated from a pyrethroid-resistant strain. Northern analysis showed that nlgst1-1 was overexpressed in resistant insects. nlgst1-1 was expressed in Escherichia coli, purified and characterized. The ability of the recombinant protein to bind to the S-hexylglutathione affinity matrix, its substrate specificities and its immunological properties confirmed that this GST was one from the elevated subset of N. lugens GSTs. Peroxidase activity of the recombinant nlgst1-1 indicated that it had a role in resistance, through detoxification of lipid peroxidation products induced by pyrethroids. Southern analysis of genomic DNA from the resistant and susceptible strains indicated that GST-based insecticide resistance may be associated with gene amplification in N. lugens. PMID:11853540

Genome-wide identification and expression analysis of glutathione S-transferase gene family in tomato: Gaining an insight to their physiological and stress-specific roles

PubMed Central

Islam, Shiful; Rahman, Iffat Ara; Islam, Tahmina

2017-01-01

Glutathione S-transferase (GST) refers to one of the major detoxifying enzymes that plays an important role in different abiotic and biotic stress modulation pathways of plant. The present study aimed to a comprehensive genome-wide functional characterization of GST genes and proteins in tomato (Solanum lycopersicum L.). The whole genome sequence analysis revealed the presence of 90 GST genes in tomato, the largest GST gene family reported till date. Eight segmental duplicated gene pairs might contribute significantly to the expansion of SlGST gene family. Based on phylogenetic analysis of tomato, rice, and Arabidopsis GST proteins, GST family members could be further divided into ten classes. Members of each orthologous class showed high conservancy among themselves. Tau and lambda are the major classes of tomato; while tau and phi are the major classes for rice and Arabidopsis. Chromosomal localization revealed highly uneven distribution of SlGST genes in 13 different chromosomes, where chromosome 9 possessed the highest number of genes. Based on publicly available microarray data, expression analysis of 30 available SlGST genes exhibited a differential pattern in all the analyzed tissues and developmental stages. Moreover, most of the members showed highly induced expression in response to multiple biotic and abiotic stress inducers that could be harmonized with the increase in total GST enzyme activity under several stress conditions. Activity of tomato GST could be enhanced further by using some positive modulators (safeners) that have been predicted through molecular docking of SlGSTU5 and ligands. Moreover, tomato GST proteins are predicted to interact with a lot of other glutathione synthesizing and utilizing enzymes such as glutathione peroxidase, glutathione reductase, glutathione synthetase and γ-glutamyltransferase. This comprehensive genome-wide analysis and expression profiling would provide a rational platform and possibility to explore the

Single nucleotide polymorphisms and microsatellites in the canine glutathione S-transferase pi 1 (GSTP1) gene promoter.

PubMed

Sacco, James; Mann, Sarah; Toral, Keller

2017-01-01

Genetic polymorphisms within the glutathione S-transferase P1 ( GSTP1 ) gene affect the elimination of toxic xenobiotics by the GSTP1 enzyme. In dogs, exposure to environmental chemicals that may be GSTP1 substrates is associated with cancer. The objectives of this study were to investigate the genetic variability in the GSTP1 promoter in a diverse population of 278 purebred dogs, compare the incidence of any variants found between breeds, and predict their effects on gene expression. To provide information on ancestral alleles, a number of wolves, coyotes, and foxes were also sequenced. Fifteen single nucleotide polymorphisms (SNPs) and two microsatellites were discovered. Three of these loci were only polymorphic in dogs while three other SNPs were unique to wolves and coyotes. The major allele at c.-46 is T in dogs but is C in the wild canids. The c.-185 delT variant was unique to dogs. The microsatellite located in the 5' untranslated region (5'UTR) was a highly polymorphic GCC tandem repeat, consisting of simple and compound alleles that varied in size from 10 to 22-repeat units. The most common alleles consisted of 11, 16, and 17-repeats. The 11-repeat allele was found in 10% of dogs but not in the other canids. Unequal recombination and replication slippage between similar and distinct alleles may be the mechanism for the multiple microsatellites observed. Twenty-eight haplotypes were constructed in the dog, and an additional 8 were observed in wolves and coyotes. While the most common haplotype acrossbreeds was the wild-type *1A(17), other prevalent haplotypes included *3A(11) in Greyhounds, *6A(16) in Labrador Retrievers, *9A(16) in Golden Retrievers, and *8A(19) in Standard Poodles. Boxers and Siberian Huskies exhibited minimal haplotypic diversity. Compared to the simple 16*1 allele, the compound 16*2 allele (found in 12% of dogs) may interfere with transcription factor binding and/or the stability of the GSTP1 transcript. Dogs and other canids exhibit

Preparation and investigation of P28GST-loaded PLGA microparticles for immunomodulation of experimental colitis.

PubMed

Thi, T H Hoang; Priemel, P A; Karrout, Y; Driss, V; Delbeke, M; Dendooven, A; Flament, M P; Capron, M; Siepmann, J

2017-11-25

The aim of this work was to prepare and characterize (in vitro and in vivo) PLGA-based microparticles loaded with an enzymatic protein derived from the helminth parasite Schistosoma haematobium: glutathione S-transferase P28GST (P28GST). This protein is not only a promising candidate vaccine against schistosomiasis, it also exhibits interesting immunomodulating effects, which can be helpful for the regulation of inflammatory diseases. Helminths express a regulatory role on intestinal inflammation, and immunization by P28GST has recently been shown to be as efficient as infection to reduce inflammation in a murine colitis model. As an alternative to the combination with a classical adjuvant, long acting P28GST microparticles were prepared in order to induce colitis prevention. PLGA was used as biodegradable and biocompatible matrix former, and a W/O/W emulsion/solvent extraction technique applied to prepare different types of microparticles. The effects of key formulation and processing parameters (e.g., the polymer molecular weight, drug loading, W/O/W phase volumes and stirring rates of the primary/secondary emulsions) on the systems' performance were studied. Microparticles providing about constant P28GST release during several weeks were selected and their effects in an experimental model of colitis evaluated. Mice received P28GST-loaded or P28GST-free PLGA microparticles (s.c.) on Day 0, and optionally also on Days 14 and 28. Colitis was induced on Day 35, the animals were sacrificed on Day 37. Interestingly, the Wallace score (being a measure of the severity of the inflammation) was significantly lower in mice treated with P28GST microparticles compared to placebo after 1 or 3 injections. As immunogenicity markers, increased anti-P28GST IgG levels were detected after three P28GST PLGA microparticle injections, but not in the control groups. Thus, the proposed microparticles offer an interesting potential for the preventive treatment of experimental colitis

Three-dimensional structure of Schistosoma japonicum glutathione S-transferase fused with a six-amino acid conserved neutralizing epitope of gp41 from HIV

NASA Technical Reports Server (NTRS)

Lim, K.; Ho, J. X.; Keeling, K.; Gilliland, G. L.; Ji, X.; Ruker, F.; Carter, D. C.

1994-01-01

The 3-dimensional crystal structure of glutathione S-transferase (GST) of Schistosoma japonicum (Sj) fused with a conserved neutralizing epitope on gp41 (glycoprotein, 41 kDa) of human immunodeficiency virus type 1 (HIV-1) (Muster T et al., 1993, J Virol 67:6642-6647) was determined at 2.5 A resolution. The structure of the 3-3 isozyme rat GST of the mu gene class (Ji X, Zhang P, Armstrong RN, Gilliland GL, 1992, Biochemistry 31:10169-10184) was used as a molecular replacement model. The structure consists of a 4-stranded beta-sheet and 3 alpha-helices in domain 1 and 5 alpha-helices in domain 2. The space group of the Sj GST crystal is P4(3)2(1)2, with unit cell dimensions of a = b = 94.7 A, and c = 58.1 A. The crystal has 1 GST monomer per asymmetric unit, and 2 monomers that form an active dimer are related by crystallographic 2-fold symmetry. In the binding site, the ordered structure of reduced glutathione is observed. The gp41 peptide (Glu-Leu-Asp-Lys-Trp-Ala) fused to the C-terminus of Sj GST forms a loop stabilized by symmetry-related GSTs. The Sj GST structure is compared with previously determined GST structures of mammalian gene classes mu, alpha, and pi. Conserved amino acid residues among the 4 GSTs that are important for hydrophobic and hydrophilic interactions for dimer association and glutathione binding are discussed.

Analysis of glutathione S-transferase Pi isoform (GSTP1) single-nucleotide polymorphisms and macular telangiectasia type 2.

PubMed

Szental, Joshua A; Baird, Paul N; Richardson, Andrea J; Islam, F M Amirul; Scholl, Hendrik P N; Charbel Issa, Peter; Holz, Frank G; Gillies, Mark; Guymer, Robyn H

2010-12-01

Recent imaging studies have suggested that macular pigment is decreased centrally in macular telangiectasia type 2 (MT2). The uptake of xanthophyll pigment into the macula is thought to be facilitated by a xanthophyll-binding protein (XBP). The Pi isoform of glutathione S-transferase (GSTP1) represents one such XBP with high binding affinity. This case-control study aimed to determine whether two common single-nucleotide polymorphisms (SNPs) of GSTP1 were associated with MT2. DNA samples from 39 cases and 21 controls were collected. Two polymorphic sites of Ile105Val and Ala114Val in exons 5 and 6 respectively, of the GSTP1 gene were analysed. Comparison of alleles and genotypes between cases and controls indicated that there were no statistically significant differences for either the Ile105Val SNP (P=0.43) or the Ala114Val SNP (P=0.85), or for any combinations; however, the homozygous at-risk genotype (GG) of the Ile105Val SNP was present in 8% of cases but absent in controls. This study found no statistically significant association between two common GSTP1 SNPs and MT2; however, a trend towards a greater frequency of the GG genotype of the Ile105Val SNP in cases is of great interest. The biological plausibility of disturbed macular pigment uptake in MT2 makes GSTP1 an excellent candidate gene. Further investigation is warranted in future studies of MT2.

Decreased expression of GST pi is correlated with a poor prognosis in human esophageal squamous carcinoma

PubMed Central

2010-01-01

Background Glutathione S-transferase pi (GST pi) is a subgroup of GST family, which provides cellular protection against free radical and carcinogenic compounds due to its detoxifying function. Expression patterns of GST pi have been studied in several carcinomas and its down-regulation was implicated to be involved in malignant transformation in patients with Barrett's esophagus. However, neither the exact role of GST pi in the pathogenesis nor its prognostic impact in squamous esophageal carcinoma is fully characterized. Methods Immunohistochemistry was used to investigate GST pi expression on 153 archival squamous esophageal carcinoma specimens with a GST pi monoclonal antibody. Statistic analyses were performed to explore its association with clinicopathological factors and clinical outcome. Results The GST pi expression was greatly reduced in tissues of esophageal carcinomas compared to adjacent normal tissues and residual benign tissues. Absent of GST pi protein expression in cytoplasm, nuclear and cytoplasm/nucleus was found in 51%, 64.7% and 48% of all the carcinoma cases, respectively. GST pi deficiency in cytoplasm, nucleus and cytoplasm/nucleus was significantly correlated to poor differentiation (p < 0.001, p < 0.001 and p < 0.001, respectively). UICC stage and T stage were found significantly correlated to negative expression of GST pi in cytoplasm (p < 0.001 and p = 0.004, respectively) and cytoplasm/nucleus (p = 0.017 and p = 0.031, respectively). In univariate analysis, absent of GST pi protein expression in cytoplasm, nucleus and cytoplasm/nucleus was significantly associated with a shorter overall survival (p < 0.001, p < 0.001 and p < 0.001, respectively), whereas only GST pi cytoplasmic staining retained an independent prognostic significance (p < 0.001) in multivariate analysis. Conclusions Our results show that GST pi expression is down regulated in the squamous esophageal carcinoma, and that the lack of GST pi expression is associated with

Glutathione S-transferase of brown planthoppers (Nilaparvata lugens) is essential for their adaptation to gramine-containing host plants.

PubMed

Sun, Xiao-Qin; Zhang, Mao-Xin; Yu, Jing-Ya; Jin, Yu; Ling, Bing; Du, Jin-Ping; Li, Gui-Hua; Qin, Qing-Ming; Cai, Qing-Nian

2013-01-01

Plants have evolved complex processes to ward off attacks by insects. In parallel, insects have evolved mechanisms to thwart these plant defenses. To gain insight into mechanisms that mediate this arms race between plants and herbivorous insects, we investigated the interactions between gramine, a toxin synthesized by plants of the family Gramineae, and glutathione S transferase (GST), an enzyme found in insects that is known to detoxify xenobiotics. Here, we demonstrate that rice (Oryza sativa), a hydrophytic plant, also produces gramine and that rice resistance to brown planthoppers (Nilaparvata lugens, BPHs) is highly associated with in planta gramine content. We also show that gramine is a toxicant that causes BPH mortality in vivo and that knockdown of BPH GST gene nlgst1-1 results in increased sensitivity to diets containing gramine. These results suggest that the knockdown of key detoxification genes in sap-sucking insects may provide an avenue for increasing their sensitivity to natural plant-associated defense mechanisms.

Glutathione S-Transferase of Brown Planthoppers (Nilaparvata lugens) Is Essential for Their Adaptation to Gramine-Containing Host Plants

PubMed Central

Yu, Jing-Ya; Jin, Yu; Ling, Bing; Du, Jin-Ping; Li, Gui-Hua; Qin, Qing-Ming; Cai, Qing-Nian

2013-01-01

Plants have evolved complex processes to ward off attacks by insects. In parallel, insects have evolved mechanisms to thwart these plant defenses. To gain insight into mechanisms that mediate this arms race between plants and herbivorous insects, we investigated the interactions between gramine, a toxin synthesized by plants of the family Gramineae, and glutathione S transferase (GST), an enzyme found in insects that is known to detoxify xenobiotics. Here, we demonstrate that rice (Oryza sativa), a hydrophytic plant, also produces gramine and that rice resistance to brown planthoppers (Nilaparvata lugens, BPHs) is highly associated with in planta gramine content. We also show that gramine is a toxicant that causes BPH mortality in vivo and that knockdown of BPH GST gene nlgst1-1 results in increased sensitivity to diets containing gramine. These results suggest that the knockdown of key detoxification genes in sap-sucking insects may provide an avenue for increasing their sensitivity to natural plant-associated defense mechanisms. PMID:23700450

Effect of Patulin from Penicillium vulpinum on the Activity of Glutathione-S-Transferase and Selected Antioxidative Enzymes in Maize

PubMed Central

Ismaiel, Ahmed A.

2017-01-01

The mycotoxin patulin (PAT) was purified from Penicillium vulpinum CM1 culture that has been isolated from a soil cultivated with maize. The effect of PAT and of a fungal culture filtrate on the activities of glutathione-S-transferase (GST) and some antioxidant enzymes viz. ascorbate peroxidase (APX), glutathione reductase (GR), dehydroascorbate reductase (DHAR) and monodehydroascorbate reductase (MDHAR) was investigated in roots and shoots of 8-day-old maize seedlings. PAT and culture filtrate caused significant reduction effects in a dose-related manner on the total GST activity. Upon application of the high PAT concentration (25 μg·mL−1) and of the concentrated fungal filtrate (100%, v/v), the reduction in GST activity of roots was 73.8–76.0% and of shoots was 60–61.7%. Conversely, significant increases in the activities of antioxidant enzymes were induced. Application of 25 μg·PAT·mL−1 increased APX, GR, DHAR, and MDHAR activity of root by 2.40-, 2.00-, 1.24-, and 2.16-fold, respectively. In shoots, the enzymatic activity was increased by 1.57-, 1.45-, 1.45-, and 1.61-fold, respectively. Similar induction values of the enzymatic activity were obtained upon application of the concentrated fungal filtrate. This is the first report describing the response of GST and antioxidant enzyme activities of plant cells to PAT toxicity. PMID:28737668

Characterization and expression profiling of glutathione S-transferases in the diamondback moth, Plutella xylostella (L.).

PubMed

You, Yanchun; Xie, Miao; Ren, Nana; Cheng, Xuemin; Li, Jianyu; Ma, Xiaoli; Zou, Minming; Vasseur, Liette; Gurr, Geoff M; You, Minsheng

2015-03-05

Glutathione S-transferases (GSTs) are multifunctional detoxification enzymes that play important roles in insects. The completion of several insect genome projects has enabled the identification and characterization of GST genes over recent years. This study presents a genome-wide investigation of the diamondback moth (DBM), Plutella xylostella, a species in which the GSTs are of special importance because this pest is highly resistant to many insecticides. A total of 22 putative cytosolic GSTs were identified from a published P. xylostella genome and grouped into 6 subclasses (with two unclassified). Delta, Epsilon and Omega GSTs were numerically superior with 5 genes for each of the subclasses. The resulting phylogenetic tree showed that the P. xylostella GSTs were all clustered into Lepidoptera-specific branches. Intron sites and phases as well as GSH binding sites were strongly conserved within each of the subclasses in the GSTs of P. xylostella. Transcriptome-, RNA-seq- and qRT-PCR-based analyses showed that the GST genes were developmental stage- and strain-specifically expressed. Most of the highly expressed genes in insecticide resistant strains were also predominantly expressed in the Malpighian tubules, midgut or epidermis. To date, this is the most comprehensive study on genome-wide identification, characterization and expression profiling of the GST family in P. xylostella. The diversified features and expression patterns of the GSTs are inferred to be associated with the capacity of this species to develop resistance to a wide range of pesticides and biological toxins. Our findings provide a base for functional research on specific GST genes, a better understanding of the evolution of insecticide resistance, and strategies for more sustainable management of the pest.

Association between glutathione S-transferase M1, P1, and NFKB1 polymorphisms and systemic lupus erythematosus susceptibility: a meta-analysis.

PubMed

Lee, Y H; Song, G G

2016-09-30

This study aimed to determine whether Glutathione S-transferase M1 (GSTM1), P1 (GSTT1), NFKB1 polymorphisms confer susceptibility to systemic lupus erythematosus (SLE). We performed a meta-analysis on the associations between GSTM1 and GSTT1 null genotypes, and NFKB1 -94 ins/delATTG polymorphisms and SLE. In total, seven studies were considered for this meta-analysis, which comprised 2,119 SLE patients and 3,014 healthy controls. Meta-analysis of the GSTM1 null polymorphism in 869 SLE and 1,544 control subjects revealed an association between SLE and the GSTM1 null genotype (OR = 1.321, 95% CI = 1.103-1.583, p = 0.002). Stratification by ethnicity indicated an association between the GSTM1 null genotype and SLE in Asians (OR = 1.334, 95% CI = 1.096-1.623, p = 0.004). However, meta-analysis of the GSTT1 null polymorphism, comprising 717 SLE and 1,008 control subjects, revealed no association between SLE and the GSTT1 null genotype overall (OR = 0.850, 95% CI = 0.687-1.051, p = 0.113) or in an Asian population (OR = 0.794, 95% CI = 0.594-1.061, p = 0.119). Meta-analysis of the NFKB1 -94 ins/delATTG polymorphism, comprising 1,250 SLE and 1,127 control subjects, revealed an association between SLE and the NFKB1 D allele (OR = 1.127, 95% CI = 1.011-1.257, p = 0.031). Ethnicity-specific meta-analysis revealed an association between the NFKB1 D allele and SLE in Asians (OR = 1.155, 95% CI = 1.026-1.300, p = 0.017). This meta-analysis demonstrates that the functional GSTM1 and NFKB1 polymorphisms are associated with the SLE risk in Asians.

Association of glutathione S-transferase pi isoform single-nucleotide polymorphisms with exudative age-related macular degeneration in a Chinese population.

PubMed

Gu, Hong; Sun, Erdan; Cui, Lei; Yang, Xiufen; Lim, Apiradee; Xu, Jun; Snellingen, Torkel; Liu, Xipu; Wang, Ningli; Liu, Ningpu

2012-10-01

To investigate the association between single-nucleotide polymorphisms in the pi isoform of glutathione S-transferase (GSTP1) gene and the risk of exudative age-related macular degeneration (AMD) in a Chinese case-control cohort. A total of 131 Chinese patients with exudative AMD and 138 control individuals were recruited. Genomic DNA was extracted from venous blood leukocytes. Two common nonsynonymous single-nucleotide polymorphisms in GSTP1 (rs1695 and rs1138272) were genotyped by polymerase chain reaction followed by allele-specific restriction enzyme digestion and direct sequencing. Significant association with exudative AMD was detected for single-nucleotide polymorphism, rs1695 (P = 0.019). The risk G allele frequencies were 21.8% in AMD patients and 12.7% in control subjects (P = 0.007). Compared with the wild-type AA genotype, odds ratio for the risk of AMD was 1.91 (95% confidence interval, 1.09-3.35) for the heterozygous AG genotype and 2.52 (95% confidence interval, 0.6-10.61) for the homozygous GG genotype. In contrast, rs1138272 was not associated with exudative AMD (P = 1.00). The risk G allele frequencies of rs1138272 were 0.4% in AMD patients and 0.4% in control subjects (P = 1.00). Our data suggest that the GSTP1 variant rs1695 moderately increases the risk of exudative AMD. The variant rs1138272 was rare and was not associated with exudative AMD in this Chinese cohort.

Decreased glutathione S-transferase expression and activity and altered sex steroids in Lake Apopka brown bullheads (Ameriurus nebulosus)

USGS Publications Warehouse

Gallagher, E.P.; Gross, T.S.; Sheehy, K.M.

2001-01-01

A number of freshwater lakes and reclaimed agricultural sites in Central Florida have been the receiving waters for agrochemical and municipal runoff. One of these sites, Lake Apopka, is also a eutrophic system that has been the focus of several case studies reporting altered reproductive activity linked to bioaccumulation of persistent organochlorine chemicals in aquatic species. The present study was initiated to determine if brown bullheads (Ameriurus nebulosus) from the north marsh of Lake Apopka (Lake Apopka Marsh) exhibit an altered capacity to detoxify environmental chemicals through hepatic glutathione S-transferase (GST)-mediated conjugation as compared with bullheads from a nearby reference site (Lake Woodruff). We also compared plasma sex hormone concentrations (testosterone, 17-?? estradiol, and 11 keto-testosterone) in bullheads from the two sites. Female bullheads from Lake Apopka had 40% lower initial rate GST conjugative activity toward 1-chloro-2,4-dinitrobenzene (CDNB), 50% lower activity towards p-nitrobutyl chloride (NBC), 33% lower activity toward ethacrynic acid (ECA), and 43% lower activity toward ??5-androstene-3,17-dione (??5-ADI), as compared with female bullheads from Lake Woodruff. Enzyme kinetic analyses demonstrated that female bullheads from Lake Apopka had lower GST-catalyzed CDNB clearance than did female Lake Woodruff bullheads. Western blotting studies of bullhead liver cytosolic proteins demonstrated that the reduced GST catalytic activities in female Lake Apopka bullheads were accompanied by lower expression of hepatic GST protein. No site differences were observed with respect to GST activities or GST protein expression in male bullheads. Female Lake Apopka bullheads also had elevated concentrations of plasma androgens (testosterone and 11-ketotestosterone) as compared with females from Lake Woodruff. In contrast, male Lake Apopka bullheads had elevated levels of plasma estrogen but similar levels of androgens as compared with

Cloning, identification and functional characterization of a pi-class glutathione-S-transferase from the freshwater mussel Cristaria plicata.

PubMed

Hu, Baoqing; Deng, Lirong; Wen, Chungen; Yang, Xilan; Pei, Pengzu; Xie, Yanhai; Luo, Shaoqing

2012-01-01

Glutathione-S-transferases (GSTs) are multifunctional phase II detoxification enzymes that catalyze the attachment of electrophilic substrates to glutathione and play an important role in protecting organisms against the toxicity of reactive oxygen species (ROS). The piGST cDNA was cloned and sequenced after rapid amplification of cDNA ends (RACE) from the freshwater mussel Cristaria plicata. The comparison of the deduced amino acid sequences with GSTs from other species showed that the enzymes belonged to the pi-class and the amino acids defining the binding sites of glutathione (G-site) and for xenobiotic substrates (H-site) were highly conserved. The Cp-piGST cDNA is 816 nucleotides (nt) in length and contained a 615 nt open reading frame (ORF) encoding 205 amino acid residues, and has 19 nt of 5' untranslated region (UTR) and a 3' UTR of 182 nt including a tailing signal (AATAAA) and a poly (A) tail. The molecular weight of the predicted piGST is 23.4 kDa, with the calculated PI being 5.2. The mRNA transcript of Cp-piGST could be detected in all the examined tissues with highest expression level in hepatopancreas. The expression level of Cp-piGST in hepatopancreas and gill showed similar trend that were significantly increased after bacterial challenge compared to the control group at 12 h. Furthermore, the recombinant Cp-piGST with high enzyme activity was induced to be expressed as a soluble form by IPTG at 20°C for 8 h, and then was purified by using the native Ni(2+) affinity chromatography. The specific activity of the purified soluble Cp-piGST enzyme into pET30 was 2.396 μmol/min/mg, and which into pET32 was 1.706 μmol/min/mg. The recombinant Cp-piGST had a maximum activity at approximately pH 8.0, and its optimum temperature was 37°C. The recombinant Cp-piGST enzyme activity became lower gradually with the denaturant concentration increasing. Copyright © 2011 Elsevier Ltd. All rights reserved.

Glutathione S-transferase (placental) as a marker of transformation in the human cervix uteri: an immunohistochemical study.

PubMed Central

Randall, B. J.; Angus, B.; Akiba, R.; Hall, A.; Cattan, A. R.; Proctor, S. J.; Jones, R. A.; Horne, C. H.

1990-01-01

Using an indirect immunohistochemical technique on paraffin sections, employing a polyclonal antibody to the acidic (placental) form of glutathione-S-transferase (GST), we have evaluated cytoplasmic and nuclear staining in a series of 67 cervical biopsies including normal non neoplastic tissue, immature squamous metaplasia, all grades of cervical intraepithelial neoplasia (CIN) and invasive carcinomas of keratinising and non-keratinising types. No differences in cytoplasmic staining between the varied lesions studied were seen. However, there were marked differences in nuclear staining. While normal non-neoplastic stratified squamous epithelium showed weak staining of the lower one-third of the epithelium only, in immature squamous metaplasia and in all grades of CIN there was intense nuclear staining in all layers of the epithelium. Invasive carcinomas showed generally less intense nuclear staining than CIN lesions. Endocervical cell nuclei also showed intense nuclear staining. These findings indicate that GST is of limited use as a marker of transformation in the human cervix uteri. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 PMID:2223578

Association of GSTM1, GSTT1 and GSTP1 Ile105Val polymorphisms with clinical response to imatinib mesylate treatment among Malaysian chronic myeloid leukaemia patients.

PubMed

Makhtar, Siti Maziras; Husin, Azlan; Baba, Abdul Aziz; Ankathil, Ravindran

2017-09-01

The detoxifying activity of glutathione S-transferases (GST) enzymes not only protect cells from the adverse effects of xenobiotics, but also alters the effectiveness of drugs in cancer cells, resulting in toxicity or drug resistance. In this study, we aimed to evaluate the association of GSTM1, GSTT1 and GSTP1 Ile105Val polymorphisms with treatment response among Malaysian chronic myeloid leukaemia (CML) patients who everyday undergo 400 mg of imatinib mesylate (IM) therapy. Multiplex polymerase chain reaction (multiplex-PCR) was performed to detect GSTM1 and GSTT1 polymorphisms simultaneously and polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis was conducted to detect the GSTP1 Ile195Val polymorphism. On evaluating the association of the variant genotype with treatment outcome, heterozygous variant (AG) and homozygous variant (GG) of GSTP1 Ile105Val showed significantly a higher risk for the development of resistance to IM with OR: 1.951 (95% CI: 1.186-3.209, P = 0.009) and OR: 3.540 (95% CI: 1.305-9.606, P = 0.013), respectively. Likewise, GSTT1 null genotype was also associated with a significantly higher risk for the development of resistance to IM with OR = 1.664 (95% CI: 1.011-2.739, P = 0.045). Our results indicate the potential usefulness of GST polymorphism genotyping in predicting the IM treatment response among CML patients.

Crystal structure of the 28 kDa glutathione S-transferase from Schistosoma haematobium.

PubMed

Johnson, Kenneth A; Angelucci, Francesco; Bellelli, Andrea; Hervé, Maxime; Fontaine, Josette; Tsernoglou, Demetrious; Capron, André; Trottein, François; Brunori, Maurizio

2003-09-02

Schistomiasis is a debilitating parasitic disease which affects 200 million people, causing life-threatening complications in 10% of the patients. This paper reports the crystal structure of the Schistosoma haematobium 28 kDa glutathione S-transferase, a multifunctional enzyme involved in host-parasite interactions and presently considered as a promising vaccine candidate against schistosomiasis. The structures of the GSH-free enzyme, as well as the partially (approximately 40%) and almost fully (approximately 80%) GSH-saturated enzyme, exhibit a unique feature, absent in previous GST structures, concerning the crucial and invariant Tyr10 side chain which occupies two alternative positions. The canonical conformer, which allows an H-bond to be formed between the side chain hydroxyl group and the activated thiolate of GSH, is somewhat less than 50% occupied. The new conformer, with the phenoxyl ring on the opposite side of the mobile loop connecting strand 1 and helix 1, is stabilized by a polar interaction with the guanidinium group of the conserved Arg21 side chain. The presence of two conformers of Tyr10 may provide a clue about clarifying the multiple catalytic functions of Sh28GST and might prove to be relevant for the design of specific antischistosomal drugs. The K(d) for GSH binding was determined by equilibrium fluorescence titrations to be approximately 3 microM and by stopped-flow rapid mixing experiments to be approximately 9 microM. The relatively tight binding of GSH by Sh28GST explains the residually bound GSH in the crystal and supports a possible role of GSH as a tightly bound cofactor involved in the catalytic mechanism for prostaglandin D(2) synthase activity.

Glutathione S-transferase activity in follicular fluid from women undergoing ovarian stimulation: role in maturation.

PubMed

Meijide, Susana; Hernández, M Luisa; Navarro, Rosaura; Larreategui, Zaloa; Ferrando, Marcos; Ruiz-Sanz, José Ignacio; Ruiz-Larrea, M Begoña

2014-10-01

Female infertility involves an emotional impact for the woman, often leading to a state of anxiety and low self-esteem. The assisted reproduction techniques (ART) are used to overcome the problem of infertility. In a first step of the in vitro fertilization therapy women are subjected to an ovarian stimulation protocol to obtain mature oocytes, which will result in competent oocytes necessary for fertilization to occur. Ovarian stimulation, however, subjects the women to a high physical and psychological stress, thus being essential to improve ART and to find biomarkers of dysfunction and fertility. GSH is an important antioxidant, and is also used in detoxification reactions, catalysed by glutathione S-transferases (GST). In the present work, we have investigated the involvement of GST in follicular maturation. Patients with fertility problems and oocyte donors were recruited for the study. From each woman follicles at two stages of maturation were extracted at the preovulatory stage. Follicular fluid was separated from the oocyte by centrifugation and used as the enzyme source. GST activity was determined based on its conjugation with 3,4-dichloronitrobenzene and the assay was adapted to a 96-well microplate reader. The absorbance was represented against the incubation time and the curves were adjusted to linearity (R(2)>0.990). Results showed that in both donors and patients GST activity was significantly lower in mature oocytes compared to small ones. These results suggest that GST may play a role in the follicle maturation by detoxifying xenobiotics, thus contributing to the normal development of the oocyte. Supported by FIS/FEDER (PI11/02559), Gobierno Vasco (Dep. Educación, Universiades e Investigación, IT687-13), and UPV/EHU (CLUMBER UFI11/20 and PES13/58). The work was approved by the Ethics Committee of the UPV/EHU (CEISH/96/2011/RUIZLARREA), and performed according to the UPV/EHU and IVI-Bilbao agreement (Ref. 2012/01). Copyright © 2014. Published by

JS-K, a glutathione S-transferase-activated nitric oxide donor with antineoplastic activity in malignant gliomas.

PubMed

Weyerbrock, Astrid; Osterberg, Nadja; Psarras, Nikolaos; Baumer, Brunhilde; Kogias, Evangelos; Werres, Anna; Bette, Stefanie; Saavedra, Joseph E; Keefer, Larry K; Papazoglou, Anna

2012-02-01

Glutathione S-transferases (GSTs) control multidrug resistance and are upregulated in many cancers, including malignant gliomas. The diazeniumdiolate JS-K generates nitric oxide (NO) on enzymatic activation by glutathione and GST, showing promising NO-based anticancer efficacy. To evaluate the role of NO-based antitumor therapy with JS-K in U87 gliomas in vitro and in vivo. U87 glioma cells and primary glioblastoma cell lines were exposed to JS-K and a variety of inhibitors to study cell death by necrosis, apoptosis, and other mechanisms. GST expression was evaluated by immunocytochemistry, polymerase chain reaction, and Western blot, and NO release from JS-K was studied with a NO assay. The growth-inhibitory effect of JS-K was studied in a U87 xenograft model in vivo. Dose-dependent inhibition of cell proliferation was observed in human U87 glioma cells and primary glioblastoma cells in vitro. Cell death was partially induced by caspase-dependent apoptosis, which could be blocked by Z-VAD-FMK and Q-VD-OPH. Inhibition of GST by sulfasalazine, cGMP inhibition by ODQ, and MEK1/2 inhibition by UO126 attenuated the antiproliferative effect of JS-K, suggesting the involvement of various intracellular death signaling pathways. Response to JS-K correlated with mRNA and protein expression of GST and the amount of NO released by the glioma cells. Growth of U87 xenografts was reduced significantly, with immunohistochemical evidence for increased necrosis and apoptosis and reduced proliferation. Our data show for the first time the potent antiproliferative effect of JS-K in gliomas in vitro and in vivo. These findings warrant further investigation of this novel NO-releasing prodrug in gliomas.

Assessment of cumulative evidence for the association between glutathione S-transferase polymorphisms and lung cancer: application of the Venice interim guidelines

PubMed Central

Langevin, Scott M.; Ioannidis, John P.A.; Vineis, Paolo; Taioli, Emanuela

2010-01-01

There is an overwhelming abundance of genetic association studies available in the literature, which often can be collectively difficult to interpret. To address this issue, the Venice interim guidelines were established for determining the credibility of the cumulative evidence. The objective of this report is to evaluate the literature on the association of common GST variants (GSTM1 null, GSTT1 null and GSTP1 Ile105Val polymorphism) and lung cancer, and to assess the credibility of the associations using the newly proposed cumulative evidence guidelines. Information from the literature was enriched with an updated meta-analysis and a pooled analysis using data from the Genetic Susceptibility to Environmental Carcinogens (GSEC) database. There was a significant association between GSTM1 null and lung cancer for the meta- (meta OR = 1.17, 95% CI: 1.10–1.25) and pooled analysis (adjusted OR = 1.10, 95% CI: 1.04–1.16), although substantial heterogeneity was present. No overall association between lung cancer and GSTT1 null or GSTP1 Ile105Val was found. When the Venice criteria was applied, cumulative evidence for all associations were considered “weak”, with the exception of East Asian carriers of the G allele of GSTP1 Ile105Val, which was graded as “moderate” evidence. In spite of large amounts of studies, and several statistically significant summary estimates produced by meta-analyses, the application of the Venice criteria suggests extensive heterogeneity and susceptibility to bias for the studies on association of common genetic polymorphisms, such as with GST variants and lung cancer. PMID:20729793

Identification and expression profiles of fifteen delta-class glutathione S-transferase genes from a stored-product pest, Liposcelis entomophila (Enderlein) (Psocoptera: Liposcelididae).

PubMed

Jing, Tian-Xing; Wu, Yu-Xian; Li, Ting; Wei, Dan-Dan; Smagghe, Guy; Wang, Jin-Jun

2017-04-01

Glutathione S-transferases (GSTs) comprise a diverse family of enzymes found ubiquitously in aerobic organisms and they play important roles in insecticide resistance. In this study, we tested the sensitivities of Liposcelis entomophila, collected from four different field populations, to three insecticides. The results showed that the insects from Tongliang population had a relatively higher tolerance to malathion and propuxor than insects from other field populations. The insecticide sensitivities of different populations detected in psocids may be due to the different control practices. Through sequence mining and phylogenetic analyses, we identified 15 delta class GST genes that contained the conserved motifs of the GSTs. Quantitative real-time PCR (Q-PCR) analysis indicated that the 15 GST genes were expressed at all tested developmental stages, and 12 GST genes had significantly higher expression levels in adulthood than in egg stage. The expression levels of 15 GST genes in different field populations showed that 9 GST genes were significantly higher in Tongliang population compared to other populations. Furthermore, Q-PCR confirmed that the expression of several delta class GSTs was upregulated at different times after malathion, propuxor and deltamethrine exposure with the LC 50 concentration of insecticide. Taken together, these findings showed that delta class GST genes have various expression levels in different developmental stages and different field populations, and they were up-regulated in response to insecticide exposure, which suggested that these GSTs may be associated with insecticide metabolism in psocids. Copyright © 2017 Elsevier Inc. All rights reserved.

Interaction between mercury (Hg), arsenic (As) and selenium (Se) affects the activity of glutathione S-transferase in breast milk; possible relationship with fish and sellfish intake.

PubMed

Gaxiola-Robles, Ramón; Labrada-Martagón, Vanessa; Celis de la Rosa, Alfredo de Jesús; Acosta-Vargas, Baudilio; Méndez-Rodríguez, Lía Celina; Zenteno-Savín, Tania

2014-08-01

Breast milk is regarded as an ideal source of nutrients for the growth and development of neonates, but it can also be a potential source of pollutants. Mothers can be exposed to different contaminants as a result of their lifestyle and environmental pollution. Mercury (Hg) and arsenic (As) could adversely affect the development of fetal and neonatal nervous system. Some fish and shellfish are rich in selenium (Se), an essential trace element that forms part of several enzymes related to the detoxification process, including glutathione S-transferase (GST). The goal of this study was to determine the interaction between Hg, As and Se and analyze its effect on the activity of GST in breast milk. Milk samples were collected from women between day 7 and 10 postpartum. The GST activity was determined spectrophotometrically; total Hg, As and Se concentrations were measured by atomic absorption spectrometry. To explain the possible association of Hg, As and Se concentrations with GST activity in breast milk, generalized linear models were constructed. The model explained 44% of the GST activity measured in breast milk. The GLM suggests that GST activity was positively correlated with Hg, As and Se concentrations. The activity of the enzyme was also explained by the frequency of consumption of marine fish and shellfish in the diet of the breastfeeding women. Copyright AULA MEDICA EDICIONES 2014. Published by AULA MEDICA. All rights reserved.

Glutathione S-transferase pi polymorphism contributes to the treatment outcomes of advanced non-small cell lung cancer patients in a Chinese population.

PubMed

Chen, J B; Wang, F; Wu, J J; Cai, M

2016-07-25

We analyzed the association between polymorphisms in three glutathione S-transferase genes (GSTP1, GSTM1, and GSTT1) and the treatment outcome for advanced non-small cell lung cancer (NSCLC). We recruited 284 NSCLC patients at advanced stage from Department of Radiotherapy in Peace Hospital Attached to Changzhi Medical College between May 2009 and May 2011, who had received cisplatin-based chemotherapy. The GSTP1, GSTM1, and GSTT1 genotyping for was determined using DNA pyrosequencing on an ABI Prism 3100 DNA analyzer. In the Cox proportional hazards model, the IIe/Val and Val/Val genotypes of GSTP1 were associated with lower risk of disease progression compared with the IIe/IIe genotype, and the HRs (95%CIs) were 0.37 (0.18-0.74) and 0.15 (0.06-0.35), respectively. The IIe/Val and Val/Val genotypes significantly decreased risk of death from all causes in patients with NSCLC, and the HRs (95%CIs) were 0.52 (0.29-0.92) and 0.37 (0.17- 0.79), respectively No significant association was observed between GSTM1 and GSTT1 polymorphisms and progression-free survival and overall survival in the NSCLC patients. In summary, we suggest that GSTP1 polymorphisms might influence the treatment outcome of advanced NSCLC patients, and our results could help improve individualized therapy.

Characterization of a lambda-cyhalothrin metabolizing glutathione S-transferase CpGSTd1 from Cydia pomonella (L.).

PubMed

Liu, Jiyuan; Yang, Xueqing; Zhang, Yalin

2014-11-01

In insects, glutathione S-transferases (GSTs) are enzymes involved in detoxification of insecticides. However, few data are available for the codling moth, Cydia pomonella (L.). In this study, we cloned a delta class GST gene CpGSTd1 from C. pomonella. Real-time quantitative PCR shows that CpGSTd1 was up-regulated with aging, and the mRNA level of CpGSTd1 was higher in the fat body and silk glands than in other tissues. The expression level of CpGSTd1 exposure to insecticide suggests that CpGSTd1 is up-regulated after chlorpyrifos-methyl and lambda-cyhalothrin treatments. Both lambda-cyhalothrin and chlorpyrifos-methyl altered GST activity in vivo. The purified CpGSTd1 protein exhibits a high catalytic efficiency with CDNB and was inhibited by lambda-cyhalothrin and chlorpyrifos-methyl in vitro. Metabolism assays indicate that lambda-cyhalothrin was significantly metabolized while chlorpyrifos-methyl was not metabolized by CpGSTd1. Binding free energy analysis suggests that CpGSTd1 binding is tighter with lambda-cyhalothrin than with chlorpyrifos-methyl. Our study suggests that CpGSTd1 plays a key role in the metabolism of insecticides in C. pomonella.

Activation and inactivation of carcinogenic dihaloalkanes and other compounds by glutathione S-transferase 5-5 in Salmonella typhimurium tester strain NM5004.

PubMed

Shimada, T; Yamazaki, H; Oda, Y; Hiratsuka, A; Watabe, T; Guengerich, F P

1996-01-01

A newly developed tester Salmonella typhimurium NM5004 strain was constructed by introducing a plasmid containing both rat GSH S-transferase (GST) 5-5 cDNA and the umuC"lacZ operon into the host strain Salmonella typhimurium TA1535 and used to examine whether or not GST modified the genotoxic activities of several dihaloalkanes and other compounds. Twenty-nine chemicals that were suggested to be conjugated by GST were compared with regard to their abilities to induce umu gene expression and cause cytotoxicity responses in both the NM5004 strain and the original tester strain (S. typhimurium TA1535/pSK1002, which is devoid of GST activity toward 1,2-epoxy-3-(4'-nitrophenoxy)propane). Ten chemicals--1,2-dibromoethane,N-(2,3-epoxypropyl)phthalimide, 1,3-dichloroacetone, CH2I2, 1,2-epoxy-3-phenoxypropane, 2,3-epoxypropyl p-methoxyphenyl ether, 1-bromo-2-chloroethane, 1-bromo-2,3-dichloropropane, CH2BrCl, and CH2Br2--were found to enhance induction of umu gene expression in the NM5004 strain as compared with the TA1535/pSK1002 strain. 1,2-Epoxy-3-(4'-nitrophenoxy)propane and 2,3-dibromo-1-chloropropane were inactivated by GST 5-5 in the NM5004 tester strain, although these chemicals were cytotoxic in both tester strains. Roles of GST 5-5 were also examined for the inactivation of reactive metabolites of several procarcinogens that were formed through oxidation by liver microsomes of polychlorinated biphenyl-treated rats. The results suggest that reactive metabolites (possibly epoxides) of aflatoxin B1, sterigmatocystin, 1,2-dihydro-1,2-dihydroxy-6-aminochrysene, and (+)- and (-)-enantiomers of 7,8-dihydroxy-7,8-dihydrobenzo[a]pyrene could be trapped as inactivated GSH conjugates in the NM5004 strain. High-performance liquid chromatographic analysis suggested that exo-aflatoxin B1-8,9-oxide--GSH conjugate was formed during the oxidation of aflatoxin B1 by rat and human liver microsomes in the presence of GSH and several GST enzymes including purified rat theta class GST

Functional complementation of anthocyanin sequestration in the vacuole by widely divergent glutathione S-transferases.

PubMed Central

Alfenito, M R; Souer, E; Goodman, C D; Buell, R; Mol, J; Koes, R; Walbot, V

1998-01-01

Glutathione S-transferases (GSTs) traditionally have been studied in plants and other organisms for their ability to detoxify chemically diverse herbicides and other toxic organic compounds. Anthocyanins are among the few endogenous substrates of plant GSTs that have been identified. The Bronze2 (Bz2) gene encodes a type III GST and performs the last genetically defined step of the maize anthocyanin pigment pathway. This step is the conjugation of glutathione to cyanidin 3-glucoside (C3G). Glutathionated C3G is transported to the vacuole via a tonoplast Mg-ATP-requiring glutathione pump (GS-X pump). Genetically, the comparable step in the petunia anthocyanin pathway is controlled by the Anthocyanin9 (An9) gene. An9 was cloned by transposon tagging and found to encode a type I plant GST. Bz2 and An9 have evolved independently from distinct types of GSTs, but each is regulated by the conserved transcriptional activators of the anthocyanin pathway. Here, a phylogenetic analysis is presented, with special consideration given to the origin of these genes and their relaxed substrate requirements. In particle bombardment tests, An9 and Bz2 functionally complement both mutants. Among several other GSTs tested, only soybean GmGST26A (previously called GmHsp26A and GH2/4) and maize GSTIII were found to confer vacuolar sequestration of anthocyanin. Previously, these genes had not been associated with the anthocyanin pathway. Requirements for An9 and Bz2 gene function were investigated by sequencing functional and nonfunctional germinal revertants of an9-T3529, bz2::Ds, and bz2::Mu1. PMID:9668133

GST-M1 is transcribed moreso than AKR7A2 in AFB₁-exposed human monocytes and lymphocytes.

PubMed

Bahari, Abbas; Mehrzad, Jalil; Mahmoudi, Mahmoud; Bassami, Mohammad Reza; Dehghani, Hesam

2015-01-01

Glutathione-S-transferases (GST) and aldo-keto reductases (AKR) are key aflatoxin (AF)-detoxifying enzymes. In this study, the expression of GST-M1, GST-T1, AKR-7A2, and AKR-7A3 genes in human monocytes and lymphocytes was analyzed after in vitro exposure to 10 or 100 ng AFB1/ml for 2 h. Unlike in pilot studies that showed that all four examined genes were present in HepG2 cells, in lymphocytes and monocytes, only GST-M1 and AKR-7A2 were detected. In fact, the induced expression of both GST-M1 and AKR-7A2 genes in human monocytes was moreso than that seen in AFB1-exposed lymphocytes. In addition, analyses of the effects of the exposures on cell cycle status were performed as, in cells lacking adequate detoxification capacities, it would be expected the cells would arrest at checkpoints in the cell cycle or progress to apoptotic/necrotic states. The results here indicated that only the high dose of AFB1 led to a change in cell cycle profiles and only in the monocytes (i.e. cells in S phase were significantly reduced). In general, the results here strongly suggest that human immune cell lineages appear to be able to increase their expression of AFB1-detoxifying enzymes (albeit to differing degrees) and, as a result, are able to counter potential toxicities from AFB1 and (likely) its metabolites.

Association of manganese superoxide dismutase and glutathione S-transferases genotypes with myocardial infarction in patients with type 2 diabetes mellitus.

PubMed

Kariž, Stojan; Nikolajević Starčević, Jovana; Petrovič, Daniel

2012-10-01

In the present study we investigated the association between genetic polymorphisms with functional effects on redox regulation: Val16Ala of manganese superoxide dismutase (MnSOD), polymorphic deletions of glutathione S-transferases M1 (GSTM1) and T1 (GSTT1) and Ile105Val of glutathione S-transferase P1 (GSTP1) and myocardial infarction (MI) in a group of patients with type 2 diabetes mellitus. The study population consisted of 463 Caucasian subjects with type 2 diabetes mellitus of more than 10 years' duration: 206 patients with MI and 257 patients with no history of coronary artery disease (CAD). Genotypes were determined by polymerase chain reaction (PCR) with restriction fragment length polymorphism (RFLP) and with multiplex PCR. The genotype distributions of tested single nucleotide polymorphisms did not show significant difference between cases and controls. After adjustment for age, gender, smoking, BMI, duration of diabetes and lipid parameters carriers of GSTM1/GSTT1-null haplotype showed an increased risk for MI (OR=3.22, 95% CI 1.37-5.04, p=0.03). The GSTM1/GSTT1 haplotype might be a genetic risk factor for MI in patients with type 2 diabetes mellitus. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

JS-K, a glutathione S-transferase-activated nitric oxide donor with antineoplastic activity in malignant gliomas

PubMed Central

Weyerbrock, Astrid; Osterberg, Nadja; Psarras, Nikolaos; Baumer, Brunhilde; Kogias, Evangelos; Werres, Anna; Bette, Stefanie; Saavedra, Joseph E.; Keefer, Larry K.; Papazoglou, Anna

2011-01-01

Background Glutathione S-transferases (GSTs) control multidrug-resistance and are upregulated in many cancers including malignant gliomas. The diazeniumdiolate JS-K generates nitric oxide (NO) on enzymatic activation by glutathione and GST, showing promising NO-based anticancer efficacy. Objective To evaluate the role of NO-based antitumor therapy with JS-K in U87 gliomas in vitro and in vivo. Methods U87 glioma cells and primary glioblastoma cell lines were exposed to JS-K and a variety of inhibitors to study cell death by necrosis, apoptosis and other mechanisms. GST-expression was evaluated by immunocytochemistry, PCR and Western blot and NO release from JS-K using a NO assay. The growth-inhibitory effect of JS-K was studied in a U87 xenograft model in vivo. Results Dose-dependent inhibition of cell proliferation was observed in human U87 glioma cells and primary glioblastoma cells in vitro. Cell death was partially induced by caspase-dependent apoptosis which could be blocked by Z-VAD-FMK and Q-VD-OPH. GST-inhibition by sulfasalazine, cGMP inhibition by ODQ and MEK 1/2 inhibition by UO126 attenuated the antiproliferative effect of JS-K, suggesting the involvement of various intracellular death signalling pathways. Response to JS-K correlated with mRNA and protein expression of GST and the amount of NO released by the glioma cells. Growth of U87 xenografts was significantly reduced, with immunohistochemical evidence for increased necrosis, apoptosis and reduced proliferation. Conclusion Our data for the first time show the potent antiproliferative effect of JS-K in gliomas in vitro and in vivo. These findings warrant further investigation of this novel NO-releasing prodrug in gliomas. PMID:21849924

Glutathione S-transferase expression and isoenzyme composition during cell differentiation of Caco-2 cells.

PubMed

Scharmach, E; Hessel, S; Niemann, B; Lampen, A

2009-11-30

The human colon adenocarcinoma cell line Caco-2 is frequently used to study human intestinal metabolism and transport of xenobiotica. Previous studies have shown that both Caco-2 cells and human colon cells constitutively express the multigene family of detoxifying enzymes glutathione S-transferases (GSTs), particularly GST alpha and GST pi. GSTs may play a fundamental role in the molecular interplay between phase I, II enzymes and ABC-transporters. The gut fermentation product, butyrate, can modulate the potential for detoxification. The aim of this study was to investigate the basal expression of further cytosolic GSTs in Caco-2 cells during cell differentiation. In addition, a comparison was made with expression levels in MCF-7 and HepG2, two other cell types with barrier functions. Finally, the butyrate-mediated modulation of gene and protein expression was determined by real time PCR and western blot analysis. In Caco-2, gene and protein expression levels of GST alpha increased during cell differentiation. High levels of GSTO1 and GSTP1 were constantly expressed. No expression of GSTM5 and GSTT1 was detected. HepG2 expressed GSTO1 and MCF-7 GSTZ1 most intensively. No expression of GSTA5, GSTM5, or GSTP1 was detected in either cell. Incubation of Caco-2 cells with butyrate (5 mM) significantly induced GSTA1 and GSTM2 in proliferating Caco-2 cells. In differentiated cells, butyrate tended to increase GSTO1 and GSTP1. The results of this study show that a differentiation-dependent expression of GSTs in Caco-2 cells may reflect the in vivo situation and indicate the potential of butyrate to modify intestinal metabolism. GSTA1-A4 have been identified as good markers for cell differentiation. The Caco-2 cell line is a useful model for assessing the potential of food-related substances to modulate the GST expression pattern.

Polymorphisms of glutathione S-transferase Mu 1 (GSTM1), Theta 1 (GSTT1), and Pi 1 (GSTP1) genes and epithelial ovarian cancer risk.

PubMed

Oliveira, Cristiane; Lourenço, Gustavo Jacob; Sagarra, Regina Aparecida Martinho; Derchain, Sophie Françoise Mauricette; Segalla, José Getulio; Lima, Carmen Silvia Passos

2012-01-01

Exposure of ovarian cells to estrogen, which is detoxified by glutathione S-transferases (GSTs), has been associated with epithelial ovarian cancer (EOC) development. We tested in this study whether the GSTM1, GSTT1 and GSTP1 Ile105Val polymorphisms alter the risk of EOC. Genomic DNA from 132 EOC patients and 132 controls was analyzed by polymerase chain reaction and restriction fragment length polymorphism methods. The differences between groups were analyzed by χ ^{2} or Fisher's exact test. The frequencies of GSTP1 Ile/Ile (57.6% versus 45.5%, P=0.03), GSTM1 null plus GSTP1 Ile/Ile (43.5% versus 25.8%; P=0.03) and GSTM1 null plus GSTT1 null plus GSTP1 Ile/Ile (30.3% versus 7.7%; P=0.007) genotypes were higher in patients than in controls. Individuals with the respective genotypes had a 1.80 (95% CI: 1.06-3.06), 2.38 (95% CI: 1.08-5.24) and 11.28 (95%CI: 1.95-65.30)-fold increased risks of EOC than those with the remaining genotypes. Our data present preliminary evidence that GSTM1, GSTT1 and GSTP1 polymorphisms, particularly in combination, constitute important inherited EOC determinants in individuals from Southeastern Brazil.

Glutathione S-transferase polymorphisms (GSTM1, GSTT1, GSTP1) and male factor infertility risk: a pooled analysis of studies.

PubMed

Safarinejad, Mohammad Reza; Dadkhah, Farid; Ali Asgari, Majid; Hosseini, Seyed Yousef; Kolahi, Ali Asgar; Iran-Pour, Elham

2012-01-01

To determine the role of glutathione S-transferases (GSTs; GSTM1, GSTT1, and GSTP1) gene polymorphisms in susceptibility to male factor infertility. We report a pooled analysis of 11 studies on the association of GSTM1, GSTT1, and GSTP1 polymorphisms and male factor infertility, including 1323 cases and 1054 controls. An overall significant association was determined between the GSTM1 null genotype [odds ratio (OR), 2.74; 95% confidence interval (CI), 1.72 to 3.84; P = .003], GSTT1 null genotype (OR, 1.54; 95% CI, 1.43 to 3.47; P = .02), and male factor infertility. The GSTP1 Ile/Val genotype had overall protective effect against development of infertility (OR, 0.48; 95% CI, 0.27 to 0.77), while there was significant heterogeneity between studies. In sensitivity analysis, two studies were excluded; the association and direction between GSTM1 and GSTT1 null genotypes and GSTP1 Ile/Val genotype and male infertility remained unchanged. There was no significant interaction between smoking status and studied genotypes on male infertility risk (P = .26). These results demonstrated that amongst populations studied to date, GSTM1 and GSTT1 null genotypes are associated with strong and modest increase in the risk of male infertility, respectively. On the contrary, GSTP1 Ile/Val genotype has protective effect.

Glutathione S-conjugates as prodrugs to target drug-resistant tumors

PubMed Central

Ramsay, Emma E.; Dilda, Pierre J.

2014-01-01

Living organisms are continuously exposed to xenobiotics. The major phase of enzymatic detoxification in many species is the conjugation of activated xenobiotics to reduced glutathione (GSH) catalyzed by the glutathione-S-transferase (GST). It has been reported that some compounds, once transformed into glutathione S-conjugates, enter the mercapturic acid pathway whose end products are highly reactive and toxic for the cell responsible for their production. The cytotoxicity of these GSH conjugates depends essentially on GST and gamma-glutamyl transferases (γGT), the enzymes which initiate the mercapturic acid synthesis pathway. Numerous studies support the view that the expression of GST and γGT in cancer cells represents an important factor in the appearance of a more aggressive and resistant phenotype. High levels of tumor GST and γGT expression were employed to selectively target tumor with GST- or γGT-activated drugs. This strategy, explored over the last two decades, has recently been successful using GST-activated nitrogen mustard (TLK286) and γGT-activated arsenic-based (GSAO and Darinaparsin) prodrugs confirming the potential of GSH-conjugates as anticancer drugs. PMID:25157234

Down-regulation of glutatione S-transferase α 4 (hGSTA4) in the muscle of thermally injured patients is indicative of susceptibility to bacterial infection

PubMed Central

Apidianakis, Yiorgos; Que, Yok-Ai; Xu, Weihong; Tegos, George P.; Zimniak, Piotr; Hamblin, Michael R.; Tompkins, Ronald G.; Xiao, Wenzhong; Rahme, Laurence G.

2012-01-01

Patients with severe burns are highly susceptible to bacterial infection. While immunosuppression facilitates infection, the contribution of soft tissues to infection beyond providing a portal for bacterial entry remains unclear. We showed previously that glutathione S-transferase S1 (gstS1), an enzyme with conjugating activity against the lipid peroxidation byproduct 4-hydroxynonenal (4HNE), is important for resistance against wound infection in Drosophila muscle. The importance of the mammalian functional counterpart of GstS1 in the context of wounds and infection has not been investigated. Here we demonstrate that the presence of a burn wound dramatically affects expression of both human (hGSTA4) and mouse (mGsta4) 4HNE scavengers. hGSTA4 is down-regulated significantly within 1 wk of thermal burn injury in the muscle and fat tissues of patients from the large-scale collaborative Inflammation and the Host Response to Injury multicentered study. Similarly, mGsta4, the murine GST with the highest catalytic efficiency for 4HNE, is down-regulated to approximately half of normal levels in mouse muscle immediately postburn. Consequently, 4HNE protein adducts are increased 4- to 5-fold in mouse muscle postburn. Using an open wound infection model, we show that deletion of mGsta4 renders mice more susceptible to infection with the prevalent wound pathogen Pseudomonas aeruginosa, while muscle hGSTA4 expression negatively correlates with burn wound infection episodes per patient. Our data suggest that hGSTA4 down-regulation and the concomitant increase in 4HNE adducts in human muscle are indicative of susceptibility to infection in individuals with severely thermal injuries.—Apidianakis, Y., Que, Y.-A., Xu, W., Tegos, G. P., Zimniak, P., Hamblin, M. R., Tompkins, R. G., Xiao, W., Rahme, L. G. Down-regulation of glutatione S-transferase α 4 (hGSTA4) in the muscle of thermally injured patients is indicative of susceptibility to bacterial infection. PMID:22038048

Testing GSTP1 genotypes and haplotypes interactions in Slovenian post-/pre-menopausal women: novel involvement of glutathione S-transferases in bone remodeling process.

PubMed

Mlakar, Simona Jurkovic; Prezelj, Janez; Marc, Janja

2012-02-01

Osteoporosis (OP) is an age-related disease associated with increased production of reactive oxygen species (ROS) and a reduction in antioxidant defense system, such as low activity of glutathione S-transferase (GST) family. The enzyme activity of the member of GSTs, GSTP1, depends on gene polymorphisms such as: Ala114Val and Ile105Val. The aim of this study was to evaluate the association between genetic polymorphisms of the GSTP1 gene and BMD variation and biochemical bone remodeling markers in 523 Slovenian pre- and post-menopausal women. Observational pilot study in a representative cohort of Slovenian patients with adjustment for potential confounders (age, height, weight, years since menopause, smoking status and glucocorticoid use) using univariate one-way and two-way analyses. Ala114Val and Ile105Val polymorphisms genotypes of GSTP1 gene, bone mineral density (BMD) values of total hip (_th), femoral neck (_fn) and lumbar spine (_ls), plasma osteocalcin (OC), serum bone alkaline phosphatase (BALP), free soluble RANKL and serum osteoprotegerin (sOPG) concentrations were determined. Our results show that the Ala114Val heterozygotes are (borderline) significantly associated with higher concentrations of pOC (p=0.052) and decreased BMD_fn values (p=0.053) and the same trend is shown for BMD_th and BMD_ls values in osteopenic postmenopausal women. Furthermore, significantly higher concentrations of pOC were determined among Val allele carriers of Ile105Val gene polymorphism (p=0.037) and in carriers with the absent 114Ala-105Ile haplotype combination, again in osteopenic post-menopausal women. In addition, in pre-menopausal women the significant associations between sOPG and Ala114Val genotypes subgroups and between sBALP and Ile105Val genotypes subgroups, alone or in combination with Ala114Val, were determined (0.032, 0.026 and 0.008, respectively). Since significant associations existed in Ala114Val genotype and 114Ala-105Ile haplotype subgroups, these

Voltage-gated sodium channel polymorphism and metabolic resistance in pyrethroid-resistant Aedes aegypti from Brazil.

PubMed

Martins, Ademir Jesus; Lins, Rachel Mazzei Moura de Andrade; Linss, Jutta Gerlinde Birgitt; Peixoto, Alexandre Afranio; Valle, Denise

2009-07-01

The nature of pyrethroid resistance in Aedes aegypti Brazilian populations was investigated. Quantification of enzymes related to metabolic resistance in two distinct populations, located in the Northeast and Southeast regions, revealed increases in Glutathione-S-transferase (GST) and Esterase levels. Additionally, polymorphism was found in the IIS6 region of Ae. aegypti voltage-gated sodium channel (AaNa(V)), the pyrethroid target site. Sequences were classified in two haplotype groups, A and B, according to the size of the intron in that region. Rockefeller, a susceptible control lineage, contains only B sequences. In field populations, some A sequences present a substitution in the 1011 site (Ile/Met). When resistant and susceptible individuals were compared, the frequency of both A (with the Met mutation) and B sequences were slightly increased in resistant specimens. The involvement of the AaNa(V) polymorphism in pyrethroid resistance and the metabolic mechanisms that lead to potential cross-resistance between organophosphate and pyrethroids are discussed.

Enhanced phytoremediation of mixed heavy metal (mercury)-organic pollutants (trichloroethylene) with transgenic alfalfa co-expressing glutathione S-transferase and human P450 2E1.

PubMed

Zhang, Yuanyuan; Liu, Junhong; Zhou, Yuanming; Gong, Tingyun; Wang, Jing; Ge, Yinlin

2013-09-15

Soil contamination is a global environmental problem and many efforts have been made to find efficient remediation methods over the last decade. Moreover, remediation of mixed contaminated soils are more difficult. In the present study, transgenic alfalfa plants pKHCG co-expressing glutathione S-transferase (GST) and human P450 2E1 (CYP2E1) genes were used for phytoremediation of mixed mercury (Hg)-trichloroethylene (TCE) contaminants. Simultaneous expression of GST and CYP2E1 may produce a significant synergistic effect, and leads to improved resistance and accumulation to heavy metal-organic complex contaminants. Based on the tolerance and accumulation assays, pKHCG transgenic plants were more resistant to Hg/TCE complex pollutants and many folds higher in Hg/TCE-accumulation than the non-transgenic control plants in mixed contaminated soil. It is confirmed that GST and CYP2E1 co-expression may be a useful strategy to help achieve mixed heavy metal-organic pollutants phytoremediation. Copyright © 2013 Elsevier B.V. All rights reserved.

Effect of a glutathione S-transferase inhibitor on oxidative stress and ischemia-reperfusion-induced apoptotic signalling of cultured cardiomyocytes

PubMed Central

Röth, E; Marczin, N; Balatonyi, B; Ghosh, S; Kovács, V; Alotti, N; Borsiczky, B; Gasz, B

2011-01-01

Oxidative stress and ischemia-reperfusion (I/R) injury are crucial in the pathogenesis of cardiovascular diseases. The antioxidant glutathione S-transferase (GST) is responsible for the high-capacity metabolic inactivation of electrophilic compounds and toxic substrates. The main objective of the present study was to examine the effect of GST inhibition (with the administration of ethacrynic acid [EA]) on the viability and apoptosis of cardiomyocytes when these cells are exposed to various stress components of I/R and mitogen-activated protein kinase (c-Jun N-terminal kinase, p38 and extracellular signal-regulated kinase [ERK]) inhibitors. The primary culture of neonatal rat cardiomyocytes was divided into six experimental groups: control group of cells (group 1), cells exposed to H2O2 (group 2), I/R (group 3), I/R and EA (group 4), H2O2 coupled with EA (group 5), and EA alone (group 6). The viability of cardiomyocytes was determined using a colorimetric MTT assay. The apoptosis ratio was evaluated via fluorescein isothiocyanate-labelled annexin V and propidium iodide staining. c-Jun N-terminal kinase, p38, Akt/protein kinase B and ERK/p42-p44 transcription factors were monitored with flow cytometry. c-Jun N-terminal kinase activation increased due to GST inhibition during I/R. EA administration led to a significant increase in p38 activation following both H2O2 treatment and I/R. ERK phosphorylation increased when GST was exposed to I/R. A pronounced decrease in Akt phosphorylation was observed when cells were cotreated with EA and H2O2. GST plays an important role as a regulator of mitogen-activated protein kinase pathways in I/R injury. PMID:22065940

Impact of the Ile105Val Polymorphism of the Glutathione S-transferase P1 (GSTP1) Gene on Obesity and Markers of Cardiometabolic Risk in Young Adult Population.

PubMed

Chielle, E O; Trott, A; da Silva Rosa, B; Casarin, J N; Fortuna, P C; da Cruz, I B M; Moretto, M B; Moresco, R N

2017-05-01

The aim of the study was to investigate the association between Glutathione S-transferase P1 (GSTP1) gene polymorphism with obesity and markers of cardiometabolic risk. A cross-sectional study was carried out in individuals aged≥18 and ≤30 years. The study included 54 normal weight, 27 overweight and 68 obese volunteers. Anthropometric measurements and biochemical parameters were evaluated, the DNA was extracted from blood samples and polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was used to measure GSTP1 Ile 105 Val gene polymorphism of the study participants. Also, biochemical analysis and hormone assays were carried out. A positive association between GSTP1 polymorphism and obesity was observed on subjects carrying at least one G allele (AG and GG). GG genotype was found only in the obese group. The G allele carriers presented 2.4 times higher chance of obesity when compared to those with the AA genotype. These results were independent of sex and age. We suggest that despite a study in population regional (south of Brazil), the GSTP1 gene polymorphism may play a significant role in the increase of susceptibility of obesity and contribute to identify the cardiovascular risk in young adults. © Georg Thieme Verlag KG Stuttgart · New York.

Characterization of the glutathione S-transferase gene family through ESTs and expression analyses within common and pigmented cultivars of Citrus sinensis (L.) Osbeck

PubMed Central

2014-01-01

Background Glutathione S-transferases (GSTs) represent a ubiquitous gene family encoding detoxification enzymes able to recognize reactive electrophilic xenobiotic molecules as well as compounds of endogenous origin. Anthocyanin pigments require GSTs for their transport into the vacuole since their cytoplasmic retention is toxic to the cell. Anthocyanin accumulation in Citrus sinensis (L.) Osbeck fruit flesh determines different phenotypes affecting the typical pigmentation of Sicilian blood oranges. In this paper we describe: i) the characterization of the GST gene family in C. sinensis through a systematic EST analysis; ii) the validation of the EST assembly by exploiting the genome sequences of C. sinensis and C. clementina and their genome annotations; iii) GST gene expression profiling in six tissues/organs and in two different sweet orange cultivars, Cadenera (common) and Moro (pigmented). Results We identified 61 GST transcripts, described the full- or partial-length nature of the sequences and assigned to each sequence the GST class membership exploiting a comparative approach and the classification scheme proposed for plant species. A total of 23 full-length sequences were defined. Fifty-four of the 61 transcripts were successfully aligned to the C. sinensis and C. clementina genomes. Tissue specific expression profiling demonstrated that the expression of some GST transcripts was 'tissue-affected' and cultivar specific. A comparative analysis of C. sinensis GSTs with those from other plant species was also considered. Data from the current analysis are accessible at http://biosrv.cab.unina.it/citrusGST/, with the aim to provide a reference resource for C. sinensis GSTs. Conclusions This study aimed at the characterization of the GST gene family in C. sinensis. Based on expression patterns from two different cultivars and on sequence-comparative analyses, we also highlighted that two sequences, a Phi class GST and a Mapeg class GST, could be involved in

Characterization of the glutathione S-transferase gene family through ESTs and expression analyses within common and pigmented cultivars of Citrus sinensis (L.) Osbeck.

PubMed

Licciardello, Concetta; D'Agostino, Nunzio; Traini, Alessandra; Recupero, Giuseppe Reforgiato; Frusciante, Luigi; Chiusano, Maria Luisa

2014-02-03

Glutathione S-transferases (GSTs) represent a ubiquitous gene family encoding detoxification enzymes able to recognize reactive electrophilic xenobiotic molecules as well as compounds of endogenous origin. Anthocyanin pigments require GSTs for their transport into the vacuole since their cytoplasmic retention is toxic to the cell. Anthocyanin accumulation in Citrus sinensis (L.) Osbeck fruit flesh determines different phenotypes affecting the typical pigmentation of Sicilian blood oranges. In this paper we describe: i) the characterization of the GST gene family in C. sinensis through a systematic EST analysis; ii) the validation of the EST assembly by exploiting the genome sequences of C. sinensis and C. clementina and their genome annotations; iii) GST gene expression profiling in six tissues/organs and in two different sweet orange cultivars, Cadenera (common) and Moro (pigmented). We identified 61 GST transcripts, described the full- or partial-length nature of the sequences and assigned to each sequence the GST class membership exploiting a comparative approach and the classification scheme proposed for plant species. A total of 23 full-length sequences were defined. Fifty-four of the 61 transcripts were successfully aligned to the C. sinensis and C. clementina genomes. Tissue specific expression profiling demonstrated that the expression of some GST transcripts was 'tissue-affected' and cultivar specific. A comparative analysis of C. sinensis GSTs with those from other plant species was also considered. Data from the current analysis are accessible at http://biosrv.cab.unina.it/citrusGST/, with the aim to provide a reference resource for C. sinensis GSTs. This study aimed at the characterization of the GST gene family in C. sinensis. Based on expression patterns from two different cultivars and on sequence-comparative analyses, we also highlighted that two sequences, a Phi class GST and a Mapeg class GST, could be involved in the conjugation of anthocyanin

Delineation of xenobiotic substrate sites in rat glutathione S-transferase M1-1

PubMed Central

Hearne, Jennifer L.; Colman, Roberta F.

2005-01-01

Glutathione S-transferases catalyze the conjugation of glutathione with endogenous and exogenous xenobiotics. Hu and Colman (1995) proposed that there are two distinct substrate sites in rat GST M1-1, a 1-chloro-2,4-dintrobenzene (CDNB) substrate site located in the vicinity of tyrosine-115, and a monobromobimane (mBBr) substrate site. To determine whether the mBBr substrate site is distinguishable from the CDNB substrate site, we tested S-(hydroxyethyl)bimane, a nonreactive derivative of mBBr, for its ability to compete kinetically with the substrates. We find that S-(hydroxyethyl)bimane is a competitive inhibitor (KI = 0.36 μM) when mBBr is used as substrate, but not when CDNB is used as substrate, demonstrating that these two sites are distinct. Using site-directed mutagenesis, we have localized the mBBr substrate site to an area midway through α-helix 4 (residues 90–114) and have identified residues that are important in the enzymatic reaction. Substitution of alanine at positions along α-helix 4 reveals that mutations at positions 103, 104, and 109 exhibit a greater perturbation of the enzymatic reaction with mBBr than with CDNB as substrate. Various other substitutions at positions 103 and 104 reveal that a hydrophobic residue is necessary at each of these positions to maintain optimal affinity of the enzyme for mBBr and preserve the secondary structure of the enzyme. Substitutions at position 109 indicate that this residue is important in the enzyme’s affinity for mBBr but has a minimal effect on Vmax. These results demonstrate that the promiscuity of rat GST M1-1 is in part due to at least two distinct substrate sites. PMID:16195544

Non-invasive delivery of dsGST is lethal to the sweet potato whitefly, Bemisia tabaci (G.) (Hemiptera: Aleyrodidae).

PubMed

Asokan, R; Rebijith, K B; Roopa, H K; Kumar, N K Krishna

2015-02-01

The sweet potato whitefly, Bemisia tabaci (G.) biotype B (Hemiptera: Aleyrodidae), is one of the most economically important pest, by being a dreaded vector of Geminiviruses, and also causes direct damage to the crops by sucking phloem sap. Glutathione S-transferase (GST) is a large family of multifunctional enzymes that play pivotal roles in the detoxification of secondary allelochemical produced by the host plants and in insecticide resistance, thus regulates insect growth and development. The objective of this study is to show the potential of RNA interference (RNAi) in the management of B. tabaci. RNAi is a sequence-specific gene silencing mechanism induced by double-stranded RNA (dsRNA) which holds tremendous potential in pest management. In this regard, we sequenced the GST from B. tabaci and synthesized approximately 500-bp dsRNA from the above and delivered through diet to B. tabaci. Real-time quantitative PCR (RT-qPCR) showed that continuous application of dsGST at 1.0, 0.5, and 0.25 μg/μl reduced mRNA expression levels for BtGST by 77.43, 64.86, and 52.95 % which resulted in mortality by 77, 59, and 40 %, respectively, after 72 h of application. Disruption of BtGST expression will enable the development of novel strategies in pest management and functional analysis of vital genes in B. tabaci.

Identification of the S-transferase like superfamily bacillithiol transferases encoded by Bacillus subtilis

PubMed Central

Perera, Varahenage R.; Lapek, John D.; Newton, Gerald L.; Gonzalez, David J.; Pogliano, Kit

2018-01-01

Bacillithiol is a low molecular weight thiol found in Firmicutes that is analogous to glutathione, which is absent in these bacteria. Bacillithiol transferases catalyze the transfer of bacillithiol to various substrates. The S-transferase-like (STL) superfamily contains over 30,000 putative members, including bacillithiol transferases. Proteins in this family are extremely divergent and are related by structural rather than sequence similarity, leaving it unclear if all share the same biochemical activity. Bacillus subtilis encodes eight predicted STL superfamily members, only one of which has been shown to be a bacillithiol transferase. Here we find that the seven remaining proteins show varying levels of metal dependent bacillithiol transferase activity. We have renamed the eight enzymes BstA-H. Mass spectrometry and gene expression studies revealed that all of the enzymes are produced to varying levels during growth and sporulation, with BstB and BstE being the most abundant and BstF and BstH being the least abundant. Interestingly, several bacillithiol transferases are induced in the mother cell during sporulation. A strain lacking all eight bacillithiol transferases showed normal growth in the presence of stressors that adversely affect growth of bacillithiol-deficient strains, such as paraquat and CdCl2. Thus, the STL bacillithiol transferases represent a new group of proteins that play currently unknown, but potentially significant roles in bacillithiol-dependent reactions. We conclude that these enzymes are highly divergent, perhaps to cope with an equally diverse array of endogenous or exogenous toxic metabolites and oxidants. PMID:29451913

Evaluation of Glutathione-S-Transferase P1 Polymorphism and its Relation to Bone Mineral Density in Egyptian Children and Adolescents with Beta-Thalassemia Major

PubMed Central

Ragab, Seham M.; Badr, Eman A.; Ibrahim, Ahmed S.

2016-01-01

Background Osteoporosis is a major complication of beta thalassemia major (TM). Increased oxidative stress and its controlling genes were linked to osteoporosis. Ile105 Val variant is a functional polymorphism of Glutathione S-transferase P1 (GSTP1), with reduced anti-oxidative property. No data are available about this variant or its association with osteoporosis among thalassemia patients yet. Objectives To investigate Ile105Val polymorphism and its possible association with bone mineral density (BMD) values in a group of TM children. Methods Thirty five TM children and 30 age and sex matched healthy controls were included. Liver and renal functions, serum ferritin, calcium, phosphorous, alkaline phosphatase and osteocalcin were assayed. BMD was determined by DXA with calculation of Z-scores at lumbar spine (LS) and femoral neck (FN). Height for age Z- score (HAZ) adjusted BMD Z-scores were calculated. GSTP1 Ile105Val polymorphism was studied by polymerase chain reaction-restriction fragment length polymorphism. Results The relative frequency of 105 Val allele was significantly higher in TM patients than the controls (p<0.0001). Significant association between genotype subgroups and BMD parameters was detected. Compared to wild homozygotes, polymorphic homozygotes had lower LS-BMD (p =0.029), LS-BMD Z –score (p=0.008 ), LS- BMD haz - Z-score (p=0.011), FN- BMD (p= 0.001), FN- BMD Z –score (p=0.02) and FN-BMD haz - Z-score (p=0.001). They exhibited higher osteocalcin levels compared to heterozygotes and wild homozygotes (p=0.012, p=0.013, respectively). Conclusion Ile105Val polymorphism was frequent among TM patients and could increase their susceptibility to reduced BMD. Large sample studies are required to confirm these findings. PMID:26740865

Erk-Creb pathway suppresses glutathione-S-transferase pi expression under basal and oxidative stress conditions in zebrafish embryos.

PubMed

Hrubik, Jelena; Glisic, Branka; Fa, Svetlana; Pogrmic-Majkic, Kristina; Andric, Nebojsa

2016-01-05

Transcriptional activation of phase II enzymes including glutathione-S-transferase pi class (Gst Pi) is important for redox regulation and defense from xenobiotics. The role of extracellular signal-regulated kinase (Erk) and protein kinase B (Akt) in regulation of Gst Pi expression has been described using adult mammalian cells. Whether these signaling pathways contribute to Gst Pi expression during embryogenesis is unknown. Using zebrafish embryo model, we provide novel evidence that Erk signaling acts as a specific suppressor of gstp1-2 mRNA during early embryogenesis. Addition of Erk inhibitor U0126 enhanced gstp1-2 mRNA expression during transition from blastula to the segmentation stage and from pharyngula until the hatching stage. Basal Erk activity did not affect gstp1-2 expression in tert-butylhydroquinone-exposed embryos. Addition of phorbol 12-myristate 13-acetate increased Erk activity leading to suppression of gstp1-2 mRNA. Activation of cAMP/Creb pathway by forskolin prevented gstp1-2 expression, whereas U0126 suppressed Creb phosphorylation, thus setting up Creb as a proximal transmitter of Erk inhibitory effect. Collectively, these findings suggest that Erk-Creb pathway exerts suppressive effect on gstp1-2 mRNA in a narrow developmental window. This study also provides a novel link between Erk and gstp1-2 expression, setting apart a possible differential regulation of gstp1-2 in adult and embryonic cells. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Characterization of equine GST A3-3 as a steroid isomerase.

PubMed

Lindström, Helena; Peer, Shawna M; Ing, Nancy H; Mannervik, Bengt

2018-04-01

Glutathione transferases (GSTs) comprise a superfamily of enzymes prominently involved in detoxication by making toxic electrophiles more polar and therefore more easily excretable. However some GSTs have developed alternative functions. Thus, a member of the Alpha class GSTs in pig and human tissues is involved in steroid hormone biosynthesis, catalyzing the obligatory double-bond isomerization of Δ 5 -androstene-3,17-dione to Δ 4 -androstene-3,17-dione and of Δ 5 -pregnene-3,20-dione to Δ 4 -pregnene-3,20-dione on the biosynthetic pathways to testosterone and progesterone. The human GST A3-3 is the most efficient steroid double-bond isomerase known so far in mammals. The current work extends discoveries of GST enzymes that act in the steroidogenic pathways in large mammals. The mRNA encoding the steroid isomerase GST A3-3 was cloned from testis of the horse (Equus ferus caballus). The concentrations of GSTA3 mRNA were highest in hormone-producing organs such as ovary, testis and adrenal gland. EcaGST A3-3 produced in E. coli has been characterized and shown to have highly efficient steroid double-bond isomerase activity, exceeding its activities with conventional GST substrates. The enzyme now ranks as one of the most efficient steroid isomerases known in mammals and approaches the activity of the bacterial ketosteroid isomerase, one of the most efficient enzymes of all categories known today. The high efficiency and the tissue distribution of EcaGST A3-3 support the view that the enzyme plays a physiologically significant role in the biosynthesis of steroid hormones. Copyright © 2017 Elsevier Ltd. All rights reserved.

Allyl isothiocyanate that induces GST and UGT expression confers oxidative stress resistance on C. elegans, as demonstrated by nematode biosensor.

PubMed

Hasegawa, Koichi; Miwa, Satsuki; Tsutsumiuchi, Kaname; Miwa, Johji

2010-02-17

Electrophilic xenobiotics and endogenous products from oxidative stresses induce the glutathione S-transferases (GSTs), which form a large family within the phase II enzymes over both animal and plant kingdoms. The GSTs thus induced in turn detoxify these external as well as internal stresses. Because these stresses are often linked to ageing and damage to health, the induction of phase II enzymes without causing adverse effects would be beneficial in slowing down ageing and keeping healthy conditions. We have tested this hypothesis by choosing allyl isothiocyanate (AITC), a functional ingredient in wasabi, as a candidate food ingredient that induces GSTs without causing adverse effects on animals' lives. To monitor the GST induction, we constructed a gst::gfp fusion gene and used it to transform Caenorhabditis elegans for use as a nematode biosensor. With the nematode biosensor, we found that AITC induced GST expression and conferred tolerance on the nematode against various oxidative stresses. We also present evidence that the transcription factor SKN-1 is involved in regulating the GST expression induced by AITC. We show the applicability of the nematode biosensor for discovering and evaluating functional food substances and chemicals that would provide anti-ageing or healthful benefits.

Genetic Polymorphisms of Glutathione S-Transferase P1 (GSTP1) and the Incidence of Anti-Tuberculosis Drug-Induced Hepatotoxicity.

PubMed

Wu, Shouquan; Wang, You-Juan; Tang, Xiaoyan; Wang, Yu; Wu, Jingcan; Ji, Guiyi; Zhang, Miaomiao; Chen, Guo; Liu, Qianqian; Sandford, Andrew J; He, Jian-Qing

2016-01-01

Anti-tuberculosis drug-induced hepatotoxicity (ATDH) is one of the most common adverse effects associated with tuberculosis (TB) therapy. Animal studies have demonstrated important roles of glutathione S-transferases in the prevention of chemical-induced hepatotoxicity. The aim of this study was to investigate the relationship between single nucleotide polymorphisms (SNPs) of glutathione S-transferase P1 (GSTP1) and ATDH in TB patients. We used two independent samples for this genetic association study. In the initial prospective study, 322 newly diagnosed TB patients were followed up for three months after initiating anti-TB therapy. In an independent retrospective study, 115 ATDH patients and 116 patients without ATDH were selected to verify the results of the prospective study. Tag-SNPs of GSTP1 were genotyped either with the MassARRAY platform or the improved multiple ligase detection reaction (iMLDR) method. The associations between SNPs and ATDH were analyzed by logistic regression analysis adjusting for confounding factors. Of the 322 patients recruited in the prospective cohort, 35 were excluded during the 3 months of follow-up, and 30 were diagnosed with ATDH and were considered as the ATDH group. The remaining 257 subjects without ATDH were considered as the non-ATDH group. After correction for potential confounding factors, significant differences were found for rs1695 (A>G) under an allelic model (OR = 3.876, 95%CI: 1.258011.905; P = 0.018). In the retrospective study, rs1695 allele A also had a higher risk of ATDH (OR = 2.10, 95%CI: 1.17-3.76; P = 0.012). We only found rs4147581AA genotype under a dominant model was related to ATDH in the prospective study (OR = 2.578, 95%CI: 1.076-6.173; P = 0.034). This is the first study to suggest that GSTP1 genotyping can be an important tool for identifying patients who are susceptible to ATDH. This result should be verified in independent large sample studies and also in other ethnic populations.

Cytokine Responses to the Anti-schistosome Vaccine Candidate Antigen Glutathione-S-transferase Vary with Host Age and Are Boosted by Praziquantel Treatment

PubMed Central

Bourke, Claire D.; Nausch, Norman; Rujeni, Nadine; Appleby, Laura J.; Trottein, François; Midzi, Nicholas; Mduluza, Takafira; Mutapi, Francisca

2014-01-01

Background Improved helminth control is required to alleviate the global burden of schistosomiasis and schistosome-associated pathologies. Current control efforts rely on the anti-helminthic drug praziquantel (PZQ), which enhances immune responses to crude schistosome antigens but does not prevent re-infection. An anti-schistosome vaccine based on Schistosoma haematobium glutathione-S-transferase (GST) is currently in Phase III clinical trials, but little is known about the immune responses directed against this antigen in humans naturally exposed to schistosomes or how these responses change following PZQ treatment. Methodology Blood samples from inhabitants of a Schistosoma haematobium-endemic area were incubated for 48 hours with or without GST before (n = 195) and six weeks after PZQ treatment (n = 107). Concentrations of cytokines associated with innate inflammatory (TNFα, IL-6, IL-8), type 1 (Th1; IFNγ, IL-2, IL-12p70), type 2 (IL-4, IL-5, IL-13), type 17 (IL-17A, IL-21, IL-23p19) and regulatory (IL-10) responses were quantified in culture supernatants via enzyme-linked immunosorbent assay (ELISA). Factor analysis and multidimensional scaling were used to analyse multiple cytokines simultaneously. Principal Findings A combination of GST-specific type 2 (IL-5 and IL-13) and regulatory (IL-10) cytokines was significantly lower in 10–12 year olds, the age group at which S. haematobium infection intensity and prevalence peak, than in 4–9 or 13+ year olds. Following PZQ treatment there was an increase in the number of participants producing detectable levels of GST-specific cytokines (TNFα, IL-6, IL-8, IFNγ, IL-12p70, IL-13 and IL-23p19) and also a shift in the GST-specific cytokine response towards a more pro-inflammatory phenotype than that observed before treatment. Participant age and pre-treatment infection status significantly influenced post-treatment cytokine profiles. Conclusions/Significance In areas where schistosomiasis is endemic host

Delineation of xenobiotic substrate sites in rat glutathione S-transferase M1-1.

PubMed

Hearne, Jennifer L; Colman, Roberta F

2005-10-01

Glutathione S-transferases catalyze the conjugation of glutathione with endogenous and exogenous xenobiotics. Hu and Colman (1995) proposed that there are two distinct substrate sites in rat GST M1-1, a 1-chloro-2,4-dintrobenzene (CDNB) substrate site located in the vicinity of tyrosine-115, and a monobromobimane (mBBr) substrate site. To determine whether the mBBr substrate site is distinguishable from the CDNB substrate site, we tested S-(hydroxyethyl)bimane, a nonreactive derivative of mBBr, for its ability to compete kinetically with the substrates. We find that S-(hydroxyethyl)bimane is a competitive inhibitor (K(I) = 0.36 microM) when mBBr is used as substrate, but not when CDNB is used as substrate, demonstrating that these two sites are distinct. Using site-directed mutagenesis, we have localized the mBBr substrate site to an area midway through alpha-helix 4 (residues 90-114) and have identified residues that are important in the enzymatic reaction. Substitution of alanine at positions along alpha-helix 4 reveals that mutations at positions 103, 104, and 109 exhibit a greater perturbation of the enzymatic reaction with mBBr than with CDNB as substrate. Various other substitutions at positions 103 and 104 reveal that a hydrophobic residue is necessary at each of these positions to maintain optimal affinity of the enzyme for mBBr and preserve the secondary structure of the enzyme. Substitutions at position 109 indicate that this residue is important in the enzyme's affinity for mBBr but has a minimal effect on Vmax. These results demonstrate that the promiscuity of rat GST M1-1 is in part due to at least two distinct substrate sites.

Gene-knockdown in the honey bee mite Varroa destructor by a non-invasive approach: studies on a glutathione S-transferase

PubMed Central

2010-01-01

Background The parasitic mite Varroa destructor is considered the major pest of the European honey bee (Apis mellifera) and responsible for declines in honey bee populations worldwide. Exploiting the full potential of gene sequences becoming available for V. destructor requires adaptation of modern molecular biology approaches to this non-model organism. Using a mu-class glutathione S-transferase (VdGST-mu1) as a candidate gene we investigated the feasibility of gene knockdown in V. destructor by double-stranded RNA-interference (dsRNAi). Results Intra-haemocoelic injection of dsRNA-VdGST-mu1 resulted in 97% reduction in VdGST-mu1 transcript levels 48 h post-injection compared to mites injected with a bolus of irrelevant dsRNA (LacZ). This gene suppression was maintained to, at least, 72 h. Total GST catalytic activity was reduced by 54% in VdGST-mu1 gene knockdown mites demonstrating the knockdown was effective at the translation step as well as the transcription steps. Although near total gene knockdown was achieved by intra-haemocoelic injection, only half of such treated mites survived this traumatic method of dsRNA administration and less invasive methods were assessed. V. destructor immersed overnight in 0.9% NaCl solution containing dsRNA exhibited excellent reduction in VdGST-mu1 transcript levels (87% compared to mites immersed in dsRNA-LacZ). Importantly, mites undergoing the immersion approach had greatly improved survival (75-80%) over 72 h, approaching that of mites not undergoing any treatment. Conclusions Our findings on V. destructor are the first report of gene knockdown in any mite species and demonstrate that the small size of such organisms is not a major impediment to applying gene knockdown approaches to the study of such parasitic pests. The immersion in dsRNA solution method provides an easy, inexpensive, relatively high throughput method of gene silencing suitable for studies in V. destructor, other small mites and immature stages of ticks

The Glutathione-S-Transferase, Cytochrome P450 and Carboxyl/Cholinesterase Gene Superfamilies in Predatory Mite Metaseiulus occidentalis

PubMed Central

Hoy, Marjorie A.

2016-01-01

Pesticide-resistant populations of the predatory mite Metaseiulus (= Typhlodromus or Galendromus) occidentalis (Arthropoda: Chelicerata: Acari: Phytoseiidae) have been used in the biological control of pest mites such as phytophagous Tetranychus urticae. However, the pesticide resistance mechanisms in M. occidentalis remain largely unknown. In other arthropods, members of the glutathione-S-transferase (GST), cytochrome P450 (CYP) and carboxyl/cholinesterase (CCE) gene superfamilies are involved in the diverse biological pathways such as the metabolism of xenobiotics (e.g. pesticides) in addition to hormonal and chemosensory processes. In the current study, we report the identification and initial characterization of 123 genes in the GST, CYP and CCE superfamilies in the recently sequenced M. occidentalis genome. The gene count represents a reduction of 35% compared to T. urticae. The distribution of genes in the GST and CCE superfamilies in M. occidentalis differs significantly from those of insects and resembles that of T. urticae. Specifically, we report the presence of the Mu class GSTs, and the J’ and J” clade CCEs that, within the Arthropoda, appear unique to Acari. Interestingly, the majority of CCEs in the J’ and J” clades contain a catalytic triad, suggesting that they are catalytically active. They likely represent two Acari-specific CCE clades that may participate in detoxification of xenobiotics. The current study of genes in these superfamilies provides preliminary insights into the potential molecular components that may be involved in pesticide metabolism as well as hormonal/chemosensory processes in the agriculturally important M. occidentalis. PMID:27467523

Combined glutathione S transferase M1/T1 null genotypes is associated with type 2 diabetes mellitus

PubMed Central

POROJAN, MIHAI D.; BALA, CORNELIA; ILIES, ROXANA; CATANA, ANDREEA; POPP, RADU A.; DUMITRASCU, DAN L.

2015-01-01

Background Due to new genetic insights, a considerably large number of genes and polymorphic gene variants are screened and linked with the complex pathogenesis of type 2 diabetes (DM). Our study aimed to investigate the association between the two isoforms of the glutathione S-transferase genes (Glutathione S transferase isoemzyme type M1- GSTM1 and Glutathione S transferase isoemzyme type T1-GSTT1) and the prevalence of DM in the Northern Romanian population. Methods We conducted a cross-sectional, randomized, case-control study evaluating the frequency of GSTM1 and GSTT1 null alleles in patients diagnosed with DM. A total of 106 patients diagnosed with DM and 124 healthy controls were included in the study. GSTM1 and GSTT1 null alleles genotyping was carried out using Multiplex PCR amplification of relevant gene fragments, followed by gel electrophoresis analysis of the resulting amplicons. Results Molecular analysis did not reveal an increased frequency of the null GSTM1 and GSTT1 alleles (mutant genotypes) respectively in the DM group compared to controls (p=0.171, OR=1.444 CI=0.852–2.447; p=0.647, OR=0.854, CI=0.436–1.673). Nevertheless, the combined GSTM1/GSTT1 null genotypes were statistically significantly higher in DM patients compared to control subjects (p=0.0021, OR=0.313, CI=0.149–0.655) Conclusions The main finding of our study is that the combined, double GSTM1/GSTT1 null genotypes are to be considered among the polymorphic genetic risk factors for type 2 DM. PMID:26528065

Glutathione Transferase from Trichoderma virens Enhances Cadmium Tolerance without Enhancing Its Accumulation in Transgenic Nicotiana tabacum

PubMed Central

Dixit, Prachy; Mukherjee, Prasun K.; Ramachandran, V.; Eapen, Susan

2011-01-01

Background Cadmium (Cd) is a major heavy metal pollutant which is highly toxic to plants and animals. Vast agricultural areas worldwide are contaminated with Cd. Plants take up Cd and through the food chain it reaches humans and causes toxicity. It is ideal to develop plants tolerant to Cd, without enhanced accumulation in the edible parts for human consumption. Glutathione transferases (GST) are a family of multifunctional enzymes known to have important roles in combating oxidative stresses induced by various heavy metals including Cd. Some GSTs are also known to function as glutathione peroxidases. Overexpression/heterologous expression of GSTs is expected to result in plants tolerant to heavy metals such as Cd. Results Here, we report cloning of a glutathione transferase gene from Trichoderma virens, a biocontrol fungus and introducing it into Nicotiana tabacum plants by Agrobacterium-mediated gene transfer. Transgenic nature of the plants was confirmed by Southern blot hybridization and expression by reverse transcription PCR. Transgene (TvGST) showed single gene Mendelian inheritance. When transgenic plants expressing TvGST gene were exposed to different concentrations of Cd, they were found to be more tolerant compared to wild type plants, with transgenic plants showing lower levels of lipid peroxidation. Levels of different antioxidant enzymes such as glutathione transferase, superoxide dismutase, ascorbate peroxidase, guiacol peroxidase and catalase showed enhanced levels in transgenic plants expressing TvGST compared to control plants, when exposed to Cd. Cadmium accumulation in the plant biomass in transgenic plants were similar or lower than wild-type plants. Conclusion The results of the present study suggest that transgenic tobacco plants expressing a Trichoderma virens GST are more tolerant to Cd, without enhancing its accumulation in the plant biomass. It should be possible to extend the present results to crop plants for developing Cd tolerance and

Detoxification enzyme activities (CYP1A1 and GST) in the skin of humpback whales as a function of organochlorine burdens and migration status.

PubMed

Bengtson Nash, S; Dawson, A; Burkhard, M; Waugh, C; Huston, W

2014-10-01

The activities of glutathione-s-transferase (GST) and cytochrome P-450 1A1 (CYP1A1) enzymes were measured in freshly extracted epidermis of live-biopsied, migrating, southern hemisphere humpback whales (Megaptera novaeangliae). The two quantified enzyme activities did not correlate strongly with each other. Similarly, neither correlated strongly with any of the organochlorine compound groups previously measured in the superficial blubber of the sample biopsy core, likely reflecting the anticipated low levels of typical aryl-hydrocarbon receptor ligands. GST activity did not differ significantly between genders or between northward (early migration) or southward (late migration) migrating cohorts. Indeed, the inter-individual variability in GST measurements was relatively low. This observation raises the possibility that measured activities were basal activities and that GST function was inherently impacted by the fasting state of the sampled animals, as seen in other species. These results do not support the implementation of CYP1A1 or GST as effective biomarkers of organochlorine contaminant burdens in southern hemisphere populations of humpback whales as advocated for other cetacean species. Further investigation of GST activity in feeding versus fasting cohorts may, however, provide some insight into the fasting metabolism of these behaviourally adapted populations. Copyright © 2014 Elsevier B.V. All rights reserved.

Biochemical Characterization and Vaccine Potential of a Heme-Binding Glutathione Transferase from the Adult Hookworm Ancylostoma caninum

PubMed Central

Zhan, Bin; Liu, Sen; Perally, Samirah; Xue, Jian; Fujiwara, Ricardo; Brophy, Peter; Xiao, Shuhua; Liu, Yueyuan; Feng, Jianjun; Williamson, Angela; Wang, Yan; Bueno, Lilian L.; Mendez, Susana; Goud, Gaddam; Bethony, Jeffrey M.; Hawdon, John M.; Loukas, Alex; Jones, Karen; Hotez, Peter J.

2005-01-01

We report the cloning and expression of Ac-GST-1, a novel glutathione S-transferase from the adult hookworm Ancylostoma caninum, and its possible role in parasite blood feeding and as a vaccine target. The predicted Ac-GST-1 open reading frame contains 207 amino acids (mass, 24 kDa) and exhibited up to 65% amino acid identity with other nematode GSTs. mRNA encoding Ac-GST-1 was detected in adults, eggs, and larval stages, but the protein was detected only in adult hookworm somatic extracts and excretory/secretory products. Using antiserum to the recombinant protein, Ac-GST-1 was immunolocalized to the parasite hypodermis and muscle tissue and weakly to the intestine. Recombinant Ac-GST-1 was enzymatically active, as determined by conjugation of glutathione to a model substrate, and exhibited a novel high-affinity binding site for hematin. The possible role of Ac-GST-1 in parasite heme detoxification during hemoglobin digestion or heme uptake prompted interest in evaluating it as a potential vaccine antigen. Vaccination of dogs with Ac-GST-1 resulted in a 39.4% reduction in the mean worm burden and 32.3% reduction in egg counts compared to control dogs following larval challenge, although the reductions were not statistically significant. However, hamsters vaccinated with Ac-GST-1 exhibited statistically significant worm reduction (53.7%) following challenge with heterologous Necator americanus larvae. These studies suggest that Ac-GST-1 is a possible drug and vaccine target for hookworm infection. PMID:16177370

Regulation of DM-20 mRNA expression and intracellular translocation of glutathione-S-transferase pi isoform during oligodendrocyte differentiation in the adult rat spinal cord.

PubMed

Kitada, Masaaki; Takeda, Kazuya; Dezawa, Mari

2016-07-01

We previously demonstrated that NG2-positive oligodendrocyte precursor cells (OPCs) do not express DM-20 mRNA and identified a distinct DM-20 mRNA-positive cell population expressing glutathione-S-transferase pi isoform (GST-pi) in the nucleus (GST-pi(Nuc)) of the adult rat spinal cord. As GST-pi intranuclear localization correlates with progenitor cell properties, we examined the differentiation status of this cell population under the intensive 5-bromo-2'-deoxyuridine (BrdU) administration method, consisting of intraperitoneal BrdU injections every 2 h for 48 h. We observed that a certain population of proliferating/proliferated cells expressed DM-20 mRNA, and sometimes two proliferating/proliferated cells were observed still attached to each other. We performed triple staining for BrdU, DM-20 mRNA, and NG2 and found pairs of neighboring BrdU-positive cells, which were considered to originate from the same progenitor cells and where both cells expressed DM-20 mRNA. Triple staining for BrdU, DM-20 mRNA, and GST-pi detected proliferating/proliferated cells exhibiting the GST-pi(Nuc)/DM-20 mRNA-positive expression pattern. These findings suggested the presence of a GST-pi(Nuc)/DM-20 mRNA-positive oligodendrocyte-lineage progenitor cell population in the adult rat spinal cord. However, we did not find any pair of neighboring BrdU-positive cells with this expression pattern. These observations collectively support the idea that GST-pi(Nuc)/DM-20 mRNA-expressing cells are the progeny of NG2-positive OPCs rather than a novel type of oligodendrocyte-lineage progenitor cells and that DM-20 mRNA expression is dynamically regulated during differentiation of OPCs into oligodendrocytes.

Expression of ovarian microsomal epoxide hydrolase and glutathione S-transferase during onset of VCD-induced ovotoxicity in B6C3F{sub 1} mice

DOE Office of Scientific and Technical Information (OSTI.GOV)

Keating, Aileen F.; Sipes, I. Glenn; Hoyer, Patricia B.

2008-07-01

4-vinylcyclohexene diepoxide (VCD) specifically destroys small pre-antral follicles in the rodent ovary. VCD can be detoxified to an inactive tetrol by microsomal epoxide hydrolase (mEH), or by conjugation to glutathione (GSH) by glutathione S-transferase (GST). Formation of VCD-GSH adducts in the mouse ovary 4 h after VCD exposure (0.57 mmol/kg/day) has been demonstrated. Because the mouse ovary expresses both mEH and GST, expression of mEH and GST pi and mu during a time-course of VCD-induced ovotoxicity was evaluated in a neonatal mouse ovarian culture system. Ovaries from postnatal day 4 (PND4) B6C3F{sub 1} mice were incubated with VCD (15 {mu}M)more » for 2, 4, 6, 8, 10, 12, or 15 days. Following incubation, ovaries were histologically evaluated, or assessed for mRNA or protein expression. VCD did not cause follicle loss (p > 0.05) on days 2, 4, or 6 of culture. At days 8, 10, 12, and 15, VCD reduced (p < 0.05) both primordial and primary follicle numbers. Increased (p < 0.05) expression of mEH, GST pi and GST mu mRNA was detected after 4 days of VCD exposure. This expression was reduced on days 6 and 8, when follicle loss was underway, but increased (p < 0.05) after 10 days of exposure. mEH and GST pi proteins were elevated (p < 0.05) following 8 days of VCD-exposure however there was no increase in GST mu protein. These findings suggest that with continuous exposure to VCD, increased expression of detoxification enzymes may participate in retarding the onset of follicle loss, but that this loss cannot ultimately be prevented.« less

2,2'-Dihydroxychalcone, a glutathione transferase inhibitor, sensitises human colon adenocarcinoma cells to chlorambucil and melphalan, but not to actinomycin D.

PubMed

Goh, Kenneth; Chen, Yufan; Zheng, Lin; Ong, Laichun; Jin, Yi; Chow, Pierce; Zhang, Kai

2008-01-01

2,2'-Dihydroxychalcone (2,2'DHC) is a potent inhibitor of glutathione S-transferases (GSTs). Pre-treatment of human colon cancer cells by a non-toxic concentration of this GST inhibitor significantly sensitised cancer cells to chlorambucil and melphalan, which are substrates of glutathione (GSH) conjugation. However, sensitisation to actinomycin D, which has not been shown to be detoxified by GSH-related mechanisms, was not observed. These results further confirm the contribution of GSH-related mechanisms to drug resistance by increased detoxification of drugs. 2,2'DHC inhibited GST activity and the transport of GSH conjugates by cancer cells. Its combined effects on GST and glutathione conjugate export (GS-X) pump may provide more potent sensitisation of cancer cells to chemotherapeutic drugs.

Isolation and characterization of a cDNA clone coding for a glutathione S-transferase class delta enzyme from the biting midge Culicoides variipennis sonorensis Wirth and Jones.

PubMed

Abdallah, M A; Pollenz, R S; Droog, F N; Nunamaker, R A; Tabachnick, W J; Murphy, K E

2000-12-01

Culicoides variipennis sonorensis is the primary vector of bluetongue viruses in North America. Glutathione S-transferases (GSTs) are enzymes that catalyze nucleophilic substitutions, converting reactive lipophilic molecules into soluble conjugates. Increased GST activity is associated with development of insecticide resistance. Described here is the isolation of the first cDNA encoding a C. variipennis GST. The clone consists of 720 translated bases encoding a protein with a M(r) of approximately 24,800 composed of 219 amino acids. The deduced amino acid sequence is similar (64%-74%) to class Delta (previously named Theta) GSTs from the dipteran genera Musca, Drosophila, Lucilia and Anopheles. The cDNA was subcloned into pET-11b, expressed in Epicurian coli BL21 (DE3) and has a specific activity of approximately 28,000 units/mg for the substrate 1-chloro-2,4-dinitrobenzene.

Phi Class of Glutathione S-transferase Gene Superfamily Widely Exists in Nonplant Taxonomic Groups.

PubMed

Munyampundu, Jean-Pierre; Xu, You-Ping; Cai, Xin-Zhong

2016-01-01

Glutathione S-transferases (GSTs) constitute a superfamily of enzymes involved in detoxification of noxious compounds and protection against oxidative damage. GST class Phi (GSTF), one of the important classes of plant GSTs, has long been considered as plant specific but was recently found in basidiomycete fungi. However, the range of nonplant taxonomic groups containing GSTFs remains unknown. In this study, the distribution and phylogenetic relationships of nonplant GSTFs were investigated. We identified GSTFs in ascomycete fungi, myxobacteria, and protists Naegleria gruberi and Aureococcus anophagefferens. GSTF occurrence in these bacteria and protists correlated with their genome sizes and habitats. While this link was missing across ascomycetes, the distribution and abundance of GSTFs among ascomycete genomes could be associated with their lifestyles to some extent. Sequence comparison, gene structure, and phylogenetic analyses indicated divergence among nonplant GSTFs, suggesting polyphyletic origins during evolution. Furthermore, in silico prediction of functional partners suggested functional diversification among nonplant GSTFs.

Phi Class of Glutathione S-transferase Gene Superfamily Widely Exists in Nonplant Taxonomic Groups

PubMed Central

Munyampundu, Jean-Pierre; Xu, You-Ping; Cai, Xin-Zhong

2016-01-01

Glutathione S-transferases (GSTs) constitute a superfamily of enzymes involved in detoxification of noxious compounds and protection against oxidative damage. GST class Phi (GSTF), one of the important classes of plant GSTs, has long been considered as plant specific but was recently found in basidiomycete fungi. However, the range of nonplant taxonomic groups containing GSTFs remains unknown. In this study, the distribution and phylogenetic relationships of nonplant GSTFs were investigated. We identified GSTFs in ascomycete fungi, myxobacteria, and protists Naegleria gruberi and Aureococcus anophagefferens. GSTF occurrence in these bacteria and protists correlated with their genome sizes and habitats. While this link was missing across ascomycetes, the distribution and abundance of GSTFs among ascomycete genomes could be associated with their lifestyles to some extent. Sequence comparison, gene structure, and phylogenetic analyses indicated divergence among nonplant GSTFs, suggesting polyphyletic origins during evolution. Furthermore, in silico prediction of functional partners suggested functional diversification among nonplant GSTFs. PMID:26884677

Expression and significance of glucose transporter-1, P-glycoprotein, multidrug resistance-associated protein and glutathione S-transferase-π in laryngeal carcinoma.

PubMed

Mao, Zhong-Ping; Zhao, Li-Jun; Zhou, Shui-Hong; Liu, Meng-Qin; Tan, Wei-Feng; Yao, Hong-Tian

2015-02-01

Increasing glucose transporter-1 (GLUT-1) activity is one of the most important ways to increase the cellular influx of glucose. We previously demonstrated that increased GLUT-1 expression was an independent predictor of survival in patients with laryngeal carcinoma. Thus, GLUT-1 may present a novel therapeutic target in laryngeal carcinoma. In this study, the expression of GLUT-1, P-glycoprotein (P-gp), multidrug resistance-associated protein 1 (MRP1) and glutathione S-transferase-π (GST-π) in laryngeal carcinomas was investigated by immunohistochemistry. Additionally, possible correlations between GLUT-1 and P-gp, MRP1 and GST-π and various clinicopathological parameters were analyzed. In this study, 52.9% (18/34), 58.8% (20/34), 20.6% (7/34) and 58.8% (20/34) of the laryngeal carcinomas were positive for GLUT-1, P-gp, MRP1 and GST-π, respectively. The expression of GLUT-1, P-gp, MRP1 and GST-π was higher in laryngeal carcinoma specimens when compared with laryngeal precancerous lesions (P<0.05). Pearson's correlation analysis showed correlations between GLUT-1 and P-gp (r=0.364; P=0.034), GLUT-1 and MRP1 (r=0.359; P=0.037) and P-gp and GST-π (r=0.426; P=0.012). GLUT-1 expression was found to significantly correlate with tumor-node-metastasis classification (P=0.02) and clinical stage (P=0.037). Furthermore, P-gp was found to significantly correlate with clinical stage (P=0.026). Univariate analysis showed that MRP1 expression was significantly associated with poor survival (c 2 =5.16; P=0.023). Multivariate analysis revealed that lymph node metastasis (P=0.009) and MRP1 overexpression (P=0.023) were significant predictors of poor survival. In the present study, the expression of GLUT-1, P-gp, MRP1 and GST-π in laryngeal carcinomas was investigated, as well as the correlations between these proteins. P-gp was found to significantly correlate with clinical stage, while MRP1 overexpression was significantly associated with poor survival.

Glutathione S-Transferase Pi-Ile 105 Val Polymorphism and Susceptibility to T2DM in Population from Turabah Region of Saudi Arabia.

PubMed

Mergani, Adil; Mansour, Ahmed Abdelkhalik; Askar, Tamer; Zahran, Rasha Nabeel; Mustafa, Adil Musa; Mohammed, Mukhtar Ahmed; Saleh, Osama Mosailhy

2016-08-01

Type 2 diabetes mellitus is characterized by chronic hyperglycemia and associated with oxidative stress resulting from accumulation of free radicals in body's tissues, which especially affects beta cells in pancreas and is an important factor in the development of diabetes and its complications. Glutathione S-transferases (GSTs) are a family of antioxidant enzymes that play important roles in decreasing ROS species and act as a kind of antioxidant defense. In a case-control study, we investigated the role of GSTP1 Ile105Val polymorphism in predisposition to T2DM in patients from Tarabah province, Saudi Arabia. The polymorphism was screened by PCR-RFLP in 90 T2DM patients and 87 healthy controls. The genotypes and alleles frequencies in cases and controls were assessed using Cochran-Armitage trend test and odds ratios (ORs), and 95 % confidence intervals (CIs) in different genetic models of inheritance were calculated. Our data indicate that G allele (Val) is associated with an increased risk for T2DM in this population in any combination (OR 4.101, 95 % CI 1.986-8.469, P = 0.00008). This indicates that individuals who are carriers for the mutant allele, either in homozygous (GG) or heterozygous (AG) state, are at fourfold higher risk for development of T2DM than other subjects in this population.

Improvement of a predictive model in ovarian cancer patients submitted to platinum-based chemotherapy: implications of a GST activity profile.

PubMed

Pereira, Deolinda; Assis, Joana; Gomes, Mónica; Nogueira, Augusto; Medeiros, Rui

2016-05-01

The success of chemotherapy in ovarian cancer (OC) is directly associated with the broad variability in platinum response, with implications in patients survival. This heterogeneous response might result from inter-individual variations in the platinum-detoxification pathway due to the expression of glutathione-S-transferase (GST) enzymes. We hypothesized that GSTM1 and GSTT1 polymorphisms might have an impact as prognostic and predictive determinants for OC. We conducted a hospital-based study in a cohort of OC patients submitted to platinum-based chemotherapy. GSTM1 and GSTT1 genotypes were determined by multiplex PCR. GSTM1-null genotype patients presented a significantly longer 5-year survival and an improved time to progression when compared with GSTM1-wt genotype patients (log-rank test, P = 0.001 and P = 0.013, respectively). Multivariate Cox regression analysis indicates that the inclusion of genetic information regarding GSTM1 polymorphism increased the predictive ability of risk of death after OC platinum-based chemotherapy (c-index from 0.712 to 0.833). Namely, residual disease (HR, 4.90; P = 0.016) and GSTM1-wt genotype emerged as more important predictors of risk of death (HR, 2.29; P = 0.039; P = 0.036 after bootstrap). No similar effect on survival was observed regarding GSTT1 polymorphism, and there were no statistically significant differences between GSTM1 and GSTT1 genotypes and the assessed patients' clinical-pathological characteristics. GSTM1 polymorphism seems to have an impact in OC prognosis as it predicts a better response to platinum-based chemotherapy and hence an improved survival. The characterization of the GSTM1 genetic profile might be a useful molecular tool and a putative genetic marker for OC clinical outcome.

Phylogenetic characterization of Clonorchis sinensis proteins homologous to the sigma-class glutathione transferase and their differential expression profiles.

PubMed

Bae, Young-An; Kim, Jeong-Geun; Kong, Yoon

2016-01-01

Glutathione transferase (GST) is one of the major antioxidant proteins with diverse supplemental activities including peroxidase, isomerase, and thiol transferase. GSTs are classified into multiple classes on the basis of their primary structures and substrate/inhibitor specificity. However, the evolutionary routes and physiological environments specific to each of the closely related bioactive enzymes remain elusive. The sigma-like GSTs exhibit amino acid conservation patterns similar to the prostaglandin D synthases (PGDSs). In this study, we analyzed the phylogenetic position of the GSTs of the biocarcinogenic liver fluke, Clonorchis sinensis. We also observed induction profile of the GSTs in association with the parasite's maturation and in response to exogenous oxidative stresses, with special attention to sigma-class GSTs and PGDSs. The C. sinensis genome encoded 12 GST protein species, which were separately assigned to cytosolic (two omega-, one zeta-, two mu-, and five sigma-class), mitochondrial (one kappa-class), and microsomal (one membrane-associated proteins in eicosanoid and glutathione metabolism-like protein) GST families. Multiple sigma GST (or PGDS) orthologs were also detected in Opisthorchis viverrini. Other trematode species possessed only a single sigma-like GST gene. A phylogenetic analysis demonstrated that one of the sigma GST lineages duplicated in the common ancestor of trematodes were specifically expanded in the opisthorchiids, but deleted in other trematodes. The induction profiles of these sigma GST genes along with the development and aging of C. sinensis, and against various exogenous chemical stimuli strongly suggest that the paralogous sigma GST genes might be undergone specialized evolution to cope with the diverse hostile biochemical environments within the mammalian hepatobiliary ductal system. Copyright © 2016 Elsevier B.V. All rights reserved.

Susceptibility to endometrial cancer: influence of allelism at p53, glutathione S-transferase (GSTM1 and GSTT1) and cytochrome P-450 (CYP1A1) loci.

PubMed Central

Esteller, M.; García, A.; Martínez-Palones, J. M.; Xercavins, J.; Reventós, J.

1997-01-01

A case-control study was designed to identify associations between polymorphisms at p53, cytochrome P-450 (CYP1A1) and glutathione-S-transferases and endometrial cancer susceptibility. Among all polymorphisms analysed, an insertional variant in p53 (P53PIN3) and two polymorphisms in the 3'-end and exon 7 of CYP1A1 showed significant association with enhanced endometrial cancer risk. Images Figure 1 Figure 2 PMID:9155064

Glutathione S-transferases act as isomerases in isomerization of 13-cis-retinoic acid to all-trans-retinoic acid in vitro.

PubMed

Chen, H; Juchau, M R

1997-11-01

A discovery that rapid enzymic isomerization of 13-cis-retinoic acid (13-cRA) to all-trans-retinoic acid (t-RA) can be catalysed by purified hepatic glutathione S-transferases (GSTs; EC 2.5.1.18) from rat is now reported. Rates of cis-trans isomerization were determined quantitatively by HPLC. GST-catalysed reactions reached equilibrium rapidly, in marked contrast with uncatalysed or GSH-catalysed isomerizations. The GST-catalysed reaction exhibited substrate saturation kinetics with a Km of approx. 8 microM. The maximal velocity of the reaction and the catalytic efficiency of GSTs were determined. The initial rate of the reaction increased linearly as a function of enzyme concentration. Catalysis by GSTs was independent of the presence of GSH, indicating that GSTs act as GSH-independent isomerases as well as transferases. Incubation with guanidine (7-8 M) or heat-inactivation of GSTs (100 degrees C for 3 min) decreased isomerase activities by approx. 50% and 75% respectively. The same heat treatment did not significantly inhibit isomerization catalysed by GSH and apoferritin, indicating that the observed decrease in isomerase activity by heat inactivation was not primarily due to oxidation of protein thiol groups in the GSTs. The specific activity of GSTs was approx. 23- and 340-fold those of GSH and apoferritin respectively when comparisons were made on the basis of free thiol concentrations, indicating that free thiol in GSTs cannot account for the majority of observed isomerase activities and suggesting that specific conformations of GSTs are important for such activities. Complete inhibition of the reaction by low concentrations of N-ethylmaleimide (10 microM) demonstrated that intact protein thiols are required for the isomerase activities of GSTs.

Common Polymorphisms in GSTA1, GSTM1 and GSTT1 Are Associated with Susceptibility to Urinary Bladder Cancer in Individuals from Balkan Endemic Nephropathy Areas of Serbia.

PubMed

Matic, Marija; Dragicevic, Biljana; Pekmezovic, Tatjana; Suvakov, Sonja; Savic-Radojevic, Ana; Pljesa-Ercegovac, Marija; Dragicevic, Dejan; Smiljic, Jelena; Simic, Tatjana

2016-09-01

Balkan endemic nephropathy (BEN) is a chronic familial form of interstitial nephritis that might eventually lead to end stage renal disease. This nephropathy affects individuals living along of the Danube River and its tributaries in Serbia, Bosnia, Croatia, Bulgaria and Romania. The increased incidence of urinary tract tumors in the BEN areas is well described, but its specific genetic predisposition is still unclear. Certain nephrocarcinogenic compounds, including those associated with BEN, are metabolized by glutathione S-transferase (GST) superfamily of phase II detoxication enzymes. Importantly, the GST-mediated detoxification may result in formation of more toxic compounds. We examined the association of common GST polymorphisms and bladder cancer (BC) risk in individuals from BEN areas in Serbia. A hospital-based case-control study included 201 BC cases (67 from BEN region) and 122 controls. Each polymorphism was identified by a PCR-based method. Individuals from BEN region with low-expression GSTA1 genotype (AB+BB) exhibited a 2.6-fold higher BC risk compared to those with GSTA1 (AA) genotype who were from non-BEN region (OR = 2.60, p = 0.015). In contrast, carriers of GSTM1-active genotype from BEN region had a 2.9-fold increased BC risk compared to those with GSTM1-active genotype from non-BEN region (OR = 2.90, p = 0.010). Likewise, carriers with GSTT1-active genotype from BEN region exhibited 2.1-fold higher BC risk compared to those from non-BEN region with GSTT1-active genotype (OR = 2.10, p = 0.027). Thus, common polymorphisms in GSTA1, GSTM1 and GSTT1 are associated with susceptibility to BC in individuals from BEN areas of Serbia.

Glutathione S-transferase polymorphisms (GSTM1, GSTT1 and GSTP1) and their susceptibility to renal cell carcinoma: an evidence-based meta-analysis.

PubMed

Yang, Xingliang; Long, Shuyu; Deng, Jianping; Deng, Tianxing; Gong, Zhihua; Hao, Ping

2013-01-01

The association of the three Glutathione S-transferases (GSTs) polymorphisms (GSTM1, GSTT1 and GSTP1) genotypes with their individual susceptibilities to renal cell carcinoma (RCC) has not been well established. We performed a quantitative meta-analysis to assess the possible associations between the GSTM1, GSTT1 and GSTP1 genotypes and their individual susceptibilities to renal cell carcinoma. We systematically searched the PubMed, CNKI and Embase databases to identify the relevant studies. Finally, 11 eligible studies were selected. The pooled odds ratios (ORs) with their 95% confidence intervals (CIs) were used to assess the association between the GSTs polymorphisms and the risk of RCC. Multiple subgroup analyses and quality assessment of the included studies were performed based on the available information. None of the GSTs polymorphisms had a significant association with the RCC risk. Similar results were found in the subgroup analyses, except for the GSTs polymorphisms in the situations described below. The GSTM1 and GSTT1 active genotypes in subjects exposed to pesticides (GSTM1: OR = 3.44; 95% CI, 2.04-5.80; GSTT1: OR = 2.84; 95% CI, 1.75-4.60), most of the GSTs genotypes in Asian populations (GSTT1: OR = 2.39, 95% CI = 1.63-3.51; GSTP1: Dominant model: OR = 1.50, 95% CI = 1.14-1.99; Additive model: OR = 1.39, 95% CI = 1.12-1.73; AG vs. AA: OR = 1.47, 95% CI = 1.10-1.97; GG vs. AA: OR = 1.82, 95% CI = 1.07-3.09) and the dual null genotype of GSTT1-GSTP1 (OR = 2.84, 95% CI = 1.75-4.60) showed positive associations with the RCC risk. Our present study provides evidence that the GSTM1, GSTT1 and GSTP1 polymorphisms are not associated with the development of RCC. However, more case-control studies are needed for further confirmation.

Transformed yeast (Schizosaccharomyces pombe) overexpressing rice Tau class glutathione S-transferase (OsGSTU30 and OsGSTU41) shows enhanced resistance to hexavalent chromium.

PubMed

Tripathi, Ankita; Indoliya, Yuvraj; Tiwari, Madhu; Tiwari, Poonam; Srivastava, Dipali; Verma, Pankaj kumar; Verma, Shikha; Gautam, Neelam; Chakrabarty, Debasis

2014-08-01

Extensive use of hexavalent chromium [Cr(VI)] in leather tanning, stainless-steel production, wood preservatives and electroplating industries has resulted in widespread environmental pollution and poses a serious threat to human health. A plant's response to Cr(VI) stress results in growth inhibition and toxicity leading to changes in components of antioxidant systems. In a previous study, we observed that a large number of glutathione S-transferase (GST) genes were up-regulated under Cr(VI) stress in rice. In this study, two rice root-specific Tau class GST genes (OsGSTU30 and OsGSTU41) were introduced into yeast (Schizosaccharomyces pombe). Transformed yeast cells overexpressing OsGSTU30 and OsGSTU41 had normal growth, but had much higher levels of GST activities and showed enhanced resistance to Cr(VI) as compared to control cells (transformed with empty vector). Also, a higher accumulation of chromium was found in the transformed yeast cells as compared to the control cells. Manipulation of glutathione biosynthesis by exogenous application of buthionine sulfoximine abolishes the protective effect of OsGSTs against Cr(VI) stress. These results suggest that Tau class OsGSTs play a significant role in detoxification of Cr(VI), probably by chelating and sequestrating glutathione-Cr(VI) complexes into vacuoles.

Analysis of glutathione S-transferase allergen cross-reactivity in a North American population: Relevance for molecular diagnosis.

PubMed

Mueller, Geoffrey A; Pedersen, Lars C; Glesner, Jill; Edwards, Lori L; Zakzuk, Josefina; London, Robert E; Arruda, Luisa Karla; Chapman, Martin D; Caraballo, Luis; Pomés, Anna

2015-11-01

It is not clear whether cross-reactivity or cosensitization to glutathione S-transferases (GSTs) occurs in tropical and subtropical environments. In the United States, Bla g 5 is the most important GST allergen and lack of coexposure to GSTs from certain species allows a better assessment of cross-reactivity. To examine the molecular structure of GST allergens from cockroach (Bla g 5), dust mites (Der p 8 and Blo t 8), and helminth (Asc s 13) for potential cross-reactive sites, and to assess the IgE cross-reactivity of sensitized patients from a temperate climate for these allergens for molecular diagnostic purposes. Four crystal structures were determined. Sera from patients allergic to cockroach and mite were tested for IgE reactivity to these GSTs. A panel of 6 murine anti-Bla g 5 mAb was assessed for cross-reactivity with the other 3 GSTs using antibody binding assays. Comparisons of the allergen structures, formed by 2-domain monomers that dimerize, revealed few contiguous regions of similar exposed residues, rendering cross-reactivity unlikely. Accordingly, anti-Bla g 5 or anti-Der p 8 IgE from North American patients did not recognize Der p 8 or Bla g 5, respectively, and neither showed binding to Blo t 8 or Asc s 13. A weaker binding of anti-Bla g 5 IgE to Der p 8 versus Bla g 5 (∼ 100-fold) was observed by inhibition assays, similar to a weak recognition of Der p 8 by anti-Bla g 5 mAb. Patients from tropical Colombia had IgE to all 4 GSTs. The lack of significant IgE cross-reactivity among the 4 GSTs is in agreement with the low shared amino acid identity at the molecular surface. Each GST is needed for accurate molecular diagnosis in different geographic areas. Copyright © 2015 American Academy of Allergy, Asthma & Immunology. All rights reserved.

[Liver cirrhosis patogenetics: polymorphism of glutation S-transferase genes].

PubMed

Goncharova, I A; Rachkovskiĭ, M I; Beloborodova, E V; Gamal' Abd El'-Aziz Nasar, Kh; Puzyrev, V P

2010-01-01

Association of deletion polymorphism in GSTT1 and GSTM1 genes and polymorphic variant A313G of GSTP1 gene with cirrhosis diseases and 4-year survival rate for the Tomsk region (West Siberia) patients were tested. Homozygous deletion of GSTM1 gene (null genotype) was a protective factor for alcoholic and mixed (HCV, HBV and alcohol) liver cirrhosis development. The patients from the joint group (all etiology forms) as well as having alcoholic and mixed cirrhosis had lower frequency of GSTM1 null genotype (39.2, 39.0, and 34.2%, respectively) in comparison with the control group (64.6%). The GSTM1 null genotype and GSTP1 gene A313G polymorphic variant correlated with the patients' survival rate. The patients survived in comparison with the dead had higher frequency of a GSTM1 null genotype (46.6 vs. 30.2%) and GSTP1 AA genotype (63.1 vs. 40.5%), and lower frequency of GSTP1 AG (A313G) genotype (31.1 vs. 51.2%). A survival rate was 2.5 times higher for patients having GSTP1 AA genotype in comparison with the GG and AG genotype carriers and 2 times higher for patients having GSTM1 null genotype than the gene carriers. A 4-year fatal case probability was 2.3 times higher among the patients having heterozygous AG GSTP1 genotype in comparison with homozygous AA and GG genotype carriers.

Superoxide dismutase, catalase, glutathione peroxidase and gluthatione S-transferases M1 and T1 gene polymorphisms in three Brazilian population groups.

PubMed

de Oliveira Hiragi, Cássia; Miranda-Vilela, Ana Luisa; Rocha, Dulce Maria Sucena; de Oliveira, Silviene Fabiana; Hatagima, Ana; de Nazaré Klautau-Guimarães, Maria

2011-01-01

Antioxidants such as superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX1) reduce the oxidation rates in the organism. Gluthatione S-transferases (GSTs) play a vital role in phase 2 of biotransformation of many substances. Variation in the expression of these enzymes suggests individual differences for the degree of antioxidant protection and geographical differences in the distribution of these variants. We described the distribution frequency of CAT (21A/T), SOD2 (Ala9Val), GPX1 (Pro198Leu), GSTM1 and GSTT1 polymorphisms in three Brazilian population groups: Kayabi Amerindians (n = 60), Kalunga Afro-descendants (n = 72), and an urban mixed population from Federal District (n = 162). Frequencies of the variants observed in Kalunga (18% to 58%) and Federal District (33% to 63%) were similar to those observed in Euro and Afro-descendants, while in Kayabi (3% to 68%), depending on the marker, frequencies were similar to the ones found in different ethnic groups. Except for SOD2 in all population groups studied here, and for GPX1 in Kalunga, the genotypic distributions were in accordance with Hardy-Weinberg Equilibrium. These data can clarify the contribution of different ethnicities in the formation of mixed populations, such as that of Brazil. Moreover, outcomes will be valuable resources for future functional studies and for genetic studies in specific populations. If these studies are designed to comprehensively explore the role of these genetic polymorphisms in the etiology of human diseases they may help to prevent inconsistent genotype-phenotype associations in pharmacogenetic studies.

Functional analysis and localisation of a delta-class glutathione S-transferase from Sarcoptes scabiei.

PubMed

Pettersson, Eva U; Ljunggren, Erland L; Morrison, David A; Mattsson, Jens G

2005-01-01

The mite Sarcoptes scabiei causes sarcoptic mange, or scabies, a disease that affects both animals and humans worldwide. Our interest in S. scabiei led us to further characterise a glutathione S-transferase. This multifunctional enzyme is a target for vaccine and drug development in several parasitic diseases. The S. scabiei glutathione S-transferase open reading frame reported here is 684 nucleotides long and yields a protein with a predicted molecular mass of 26 kDa. Through phylogenetic analysis the enzyme was classified as a delta-class glutathione S-transferase, and our paper is the first to report that delta-class glutathione S-transferases occur in organisms other than insects. The recombinant S. scabiei glutathione S-transferase was expressed in Escherichia coli via three different constructs and purified for biochemical analysis. The S. scabiei glutathione S-transferase was active towards the substrate 1-chloro-2,4-dinitrobenzene, though the positioning of fusion partners influenced the kinetic activity of the enzyme. Polyclonal antibodies raised against S. scabiei glutathione S-transferase specifically localised the enzyme to the integument of the epidermis and cavities surrounding internal organs in adult parasites. However, some minor staining of parasite intestines was observed. No staining was seen in host tissues, nor could we detect any antibody response against S. scabiei glutathione S-transferase in sera from naturally S. scabiei infected dogs or pigs. Additionally, the polyclonal sera raised against recombinant S. scabiei glutathione S-transferase readily detected a protein from mites, corresponding to the predicted size of native glutathione S-transferase.

Micro-Plasticity of Genomes As Illustrated by the Evolution of Glutathione Transferases in 12 Drosophila Species

PubMed Central

Saisawang, Chonticha; Ketterman, Albert J.

2014-01-01

Glutathione transferases (GST) are an ancient superfamily comprising a large number of paralogous proteins in a single organism. This multiplicity of GSTs has allowed the copies to diverge for neofunctionalization with proposed roles ranging from detoxication and oxidative stress response to involvement in signal transduction cascades. We performed a comparative genomic analysis using FlyBase annotations and Drosophila melanogaster GST sequences as templates to further annotate the GST orthologs in the 12 Drosophila sequenced genomes. We found that GST genes in the Drosophila subgenera have undergone repeated local duplications followed by transposition, inversion, and micro-rearrangements of these copies. The colinearity and orientations of the orthologous GST genes appear to be unique in many of the species which suggests that genomic rearrangement events have occurred multiple times during speciation. The high micro-plasticity of the genomes appears to have a functional contribution utilized for evolution of this gene family. PMID:25310450

Dual-phase 99mTc-MIBI imaging and the expressions of P-gp, GST-π, and MRP1 in hyperparathyroidism.

PubMed

Xue, Jianjun; Liu, Yan; Yang, Danrong; Yu, Yan; Geng, Qianqian; Ji, Ting; Yang, Lulu; Wang, Qi; Wang, Yuanbo; Lu, Xueni; Yang, Aimin

2017-10-01

The aim of this study was to further elucidate the mechanisms of dual-phase technetium-99m methoxyisobutylisonitrile (Tc-MIBI) parathyroid imaging by exploring the association between early uptake results (EUR), delayed uptake results (DUR), and the retention index (RI) in dual-phase Tc-MIBI parathyroid imaging and P glycoprotein (P-gp), multidrug resistance-associated protein 1 (MRP1), and glutathione S-transferase-π (GST-π) expression in hyperparathyroidism (HPT). Preoperative dual-phase (early and delayed) Tc-MIBI imaging was performed on 74 patients undergoing parathyroidectomy for HPT. EUR, DUR, and RI were calculated. P-gp, MRP1, and GST-π expressions were assessed using immunohistochemistry in resected tissue from HPT and control patients. The association between P-gp, MRP1, and GST-π expressions and EUR, DUR, and RI in HPT was evaluated. The positive rate of dual-phase T c-MIBI imaging was 91.89% (68/74) and the false-negative rate was 8.11% (6/74). P-gp and GST-π expressions were higher in tissues resected from control compared with HPT patients (47.37 and 81.5%, P<0.05); there was no difference in MRP1. EUR were associated with P-gp and GST-π expressions, and DUR were associated with MRP1 expression. There was a significant difference in MRP1 expression between RI greater than or equal to 0 and RI less than 0. There was no relationship between the sensitivity of dual-phase Tc-MIBI imaging and P-gp, MRP1, and GST-π expressions in resected parathyroid tissue. The six false-negative HPT cases consisted of three P-gp (-)/MRP1 (-) tissues, three P-gp (-)/GST-π (-) tissues, and four MRP1 (-)/GST-π (-) tissues. As P-gp and GST-π expressions were higher in tissues resected from control compared with HPT patients, Tc-MIBI may wash out faster from normal parathyroid tissue surrounding the lesion compared with the lesion itself, facilitating detection.

Association between glutathione S-transferase P1 Ile (105) Val gene polymorphism and chronic obstructive pulmonary disease: A meta-analysis based on seventeen case-control studies.

PubMed

Yang, Lingjing; Li, Xixia; Tong, Xiang; Fan, Hong

2015-12-01

Previous studies have shown that glutathione S-transferase P1 (GSTP1) was associated with chronic obstructive pulmonary disease (COPD). However, the association between GSTP1 Ile (105) Val gene polymorphism and COPD remains controversial. To drive a more precise estimation, we performed a meta-analysis based on published case-control studies. An electronic search of PubMed, EMBASE, Cochrane library, Web of Science and China Knowledge Resource Integrated (CNKI) Database for papers on GSTP1 Ile (105) Val gene polymorphism and COPD risk was performed. The pooled odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the strength of association in the homozygote model, heterozygote model, dominant model, recessive model and an additive mode. Statistical heterogeneity, test of publication bias and sensitivity analysis was performed. The software STATA (Version 13.0) was used data analysis. Overall, seventeen studies with 1892 cases and 2012 controls were included in this meta-analysis. The GSTP1 Ile (105) Val polymorphism showed pooled odds ratios for the homozygote comparison (OR = 1.501, 95%CI [0.862, 2.614]), heterozygote comparison (OR = 0.924, 95%CI [0.733, 1.165]), dominant model (OR = 1.003, 95%CI [0.756, 1.331]), recessive model (OR = 1.510, 95%CI [0.934, 2.439]), and an additive model (OR = 1.072, 95%CI [0.822, 1.398]). In conclusion, the current meta-analysis, based on the most updated information, showed no significant association between GSTP1 Ile (105) Val gene polymorphism and COPD risk in any genetic models. The results of subgroup analysis also showed no significant association between GSTP1 Ile (105) Val gene polymorphism and COPD risk in Asian population and Caucasian population. Further studies involving large populations and careful control with age, sex, ethnicity, and cigarette smoking are greatly needed.

Association between glutathione S-transferase P1 Ile (105) Val gene polymorphism and chronic obstructive pulmonary disease: A meta-analysis based on seventeen case–control studies

PubMed Central

Yang, Lingjing; Li, Xixia; Tong, Xiang; Fan, Hong

2015-01-01

Introduction Previous studies have shown that glutathione S-transferase P1 (GSTP1) was associated with chronic obstructive pulmonary disease (COPD). However, the association between GSTP1 Ile (105) Val gene polymorphism and COPD remains controversial. To drive a more precise estimation, we performed a meta-analysis based on published case–control studies. Methods An electronic search of PubMed, EMBASE, Cochrane library, Web of Science and China Knowledge Resource Integrated (CNKI) Database for papers on GSTP1 Ile (105) Val gene polymorphism and COPD risk was performed. The pooled odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the strength of association in the homozygote model, heterozygote model, dominant model, recessive model and an additive mode. Statistical heterogeneity, test of publication bias and sensitivity analysis was performed. The software STATA (Version 13.0) was used data analysis. Results Overall, seventeen studies with 1892 cases and 2012 controls were included in this meta-analysis. The GSTP1 Ile (105) Val polymorphism showed pooled odds ratios for the homozygote comparison (OR = 1.501, 95%CI [0.862, 2.614]), heterozygote comparison (OR = 0.924, 95%CI [0.733, 1.165]), dominant model (OR = 1.003, 95%CI [0.756, 1.331]), recessive model (OR = 1.510, 95%CI [0.934, 2.439]), and an additive model (OR = 1.072, 95%CI [0.822, 1.398]). Conclusions In conclusion, the current meta-analysis, based on the most updated information, showed no significant association between GSTP1 Ile (105) Val gene polymorphism and COPD risk in any genetic models. The results of subgroup analysis also showed no significant association between GSTP1 Ile (105) Val gene polymorphism and COPD risk in Asian population and Caucasian population. Further studies involving large populations and careful control with age, sex, ethnicity, and cigarette smoking are greatly needed. PMID:26504746

Glutathione S-transferases act as isomerases in isomerization of 13-cis-retinoic acid to all-trans-retinoic acid in vitro.

PubMed Central

Chen, H; Juchau, M R

1997-01-01

A discovery that rapid enzymic isomerization of 13-cis-retinoic acid (13-cRA) to all-trans-retinoic acid (t-RA) can be catalysed by purified hepatic glutathione S-transferases (GSTs; EC 2.5.1.18) from rat is now reported. Rates of cis-trans isomerization were determined quantitatively by HPLC. GST-catalysed reactions reached equilibrium rapidly, in marked contrast with uncatalysed or GSH-catalysed isomerizations. The GST-catalysed reaction exhibited substrate saturation kinetics with a Km of approx. 8 microM. The maximal velocity of the reaction and the catalytic efficiency of GSTs were determined. The initial rate of the reaction increased linearly as a function of enzyme concentration. Catalysis by GSTs was independent of the presence of GSH, indicating that GSTs act as GSH-independent isomerases as well as transferases. Incubation with guanidine (7-8 M) or heat-inactivation of GSTs (100 degrees C for 3 min) decreased isomerase activities by approx. 50% and 75% respectively. The same heat treatment did not significantly inhibit isomerization catalysed by GSH and apoferritin, indicating that the observed decrease in isomerase activity by heat inactivation was not primarily due to oxidation of protein thiol groups in the GSTs. The specific activity of GSTs was approx. 23- and 340-fold those of GSH and apoferritin respectively when comparisons were made on the basis of free thiol concentrations, indicating that free thiol in GSTs cannot account for the majority of observed isomerase activities and suggesting that specific conformations of GSTs are important for such activities. Complete inhibition of the reaction by low concentrations of N-ethylmaleimide (10 microM) demonstrated that intact protein thiols are required for the isomerase activities of GSTs. PMID:9581548

Cloning and characterization of a novel sigma-like glutathione S-transferase from the giant panda parasitic nematode, Baylisascaris schroederi.

PubMed

Xie, Yue; Zhou, Xuan; Chen, Lin; Zhang, Zhihe; Wang, Chengdong; Gu, Xiaobin; Wang, Tao; Peng, Xuerong; Yang, Guangyou

2015-01-23

Baylisascaris schroederi, an intestinal nematode of the giant panda, is the cause of the often fatal disease, baylisascariasis. Glutathione S-transferases (GSTs) are versatile enzymes that can affect parasite survival and parasite-host interactions and, are therefore, potential targets for the development of diagnostic tests and vaccines. In this study, we identified a full-length cDNA that encoded a novel, secretory sigma-like GST (Bsc-GSTσ) from a B. schroederi-omic dataset. Following cloning and sequencing, sequence and structural analyses and comparative modeling were performed using online-bioinformatics and proteomics tools. The recombinant Bsc-GSTσ (rBsc-GSTσ) protein was prokaryotically expressed and then used to detect antigenicity and reactivity using immunoblotting assays. In addition, the native protein in female adult B. schroederi was located via immunofluorescence techniques, while the preliminary ELISA-based serodiagnostic potential of rBsc-GSTσ was assessed in native and infected mouse sera. Bsc-GSTσ contained a 621-bp open reading frame that encoded a polypeptide of 206 amino acids with two typical sigma GST domain profiles, including a GST_N_Sigma_like at the N-terminus and a GST_C_Sigma_like at the C-terminus. The presence of an N-terminal signal sequence indicated that Bsc-GSTσ was a secretory protein. Sequence alignment and phylogenetic analyses showed that Bsc-GSTσ was a nematode-specific member of the Sigma class GSTs and shared the closest genetic distance with its homologue in Ascaris suum. Further comparative structure analyses indicated that Bsc-GSTσ possessed the essential structural motifs (e.g., βαβαββα) and the consensus secondary or tertiary structure that is typical for other characterized GSTσs. Immunolocalization revealed strong distributions of native Bsc-GSTσ in the body hypodermis, lateral chords, gut epithelium, gut microvilli, oviduct epithelium, and ovaries of adult female worms, similar to its homologue in

Characterization of liver injury, oval cell proliferation and cholangiocarcinogenesis in glutathione S-transferase A3 knockout mice.

PubMed

Crawford, Dana R; Ilic, Zoran; Guest, Ian; Milne, Ginger L; Hayes, John D; Sell, Stewart

2017-07-01

We recently generated glutathione S-transferase (GST) A3 knockout (KO) mice as a novel model to study the risk factors for liver cancer. GSTA3 KO mice are sensitive to the acute cytotoxic and genotoxic effects of aflatoxin B1 (AFB1), confirming the crucial role of GSTA3 in resistance to AFB1. We now report histopathological changes, tumor formation, biochemical changes and gender response following AFB1 treatment as well as the contribution of oxidative stress. Using a protocol of weekly 0.5 mg AFB1/kg administration, we observed extensive oval (liver stem) cell (OC) proliferation within 1-3 weeks followed by microvesicular lipidosis, megahepatocytes, nuclear inclusions, cholangiomas and small nodules. Male and female GSTA3 KO mice treated with 12 and 24 weekly AFB1 injections followed by a rest period of 12 and 6 months, respectively, all had grossly distorted livers with macro- and microscopic cysts, hepatocellular nodules, cholangiomas and cholangiocarcinomas and OC proliferation. We postulate that the prolonged AFB1 treatment leads to inhibition of hepatocyte proliferation, which is compensated by OC proliferation and eventually formation of cholangiocarcinoma (CCA). At low-dose AFB1, male KO mice showed less extensive acute liver injury, OC proliferation and AFB1-DNA adducts than female KO mice. There were no significant compensatory changes in KO mice GST subunits, GST enzymatic activity, epoxide hydrolase, or CYP1A2 and CYP3A11 levels. Finally, there was a modest increase in F2-isoprostane and isofuran in KO mice that confirmed putative GSTA3 hydroperoxidase activity in vivo for the first time. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Expression profiling of selected glutathione transferase genes in Zea mays (L.) seedlings infested with cereal aphids.

PubMed

Sytykiewicz, Hubert; Chrzanowski, Grzegorz; Czerniewicz, Paweł; Sprawka, Iwona; Łukasik, Iwona; Goławska, Sylwia; Sempruch, Cezary

2014-01-01

The purpose of this report was to evaluate the expression patterns of selected glutathione transferase genes (gst1, gst18, gst23 and gst24) in the tissues of two maize (Zea mays L.) varieties (relatively resistant Ambrozja and susceptible Tasty Sweet) that were colonized with oligophagous bird cherry-oat aphid (Rhopalosiphum padi L.) or monophagous grain aphid (Sitobion avenae L.). Simultaneously, insect-triggered generation of superoxide anion radicals (O2•-) in infested Z. mays plants was monitored. Quantified parameters were measured at 1, 2, 4, 8, 24, 48 and 72 h post-initial aphid infestation (hpi) in relation to the non-infested control seedlings. Significant increases in gst transcript amounts were recorded in aphid-stressed plants in comparison to the control seedlings. Maximal enhancement in the expression of the gst genes in aphid-attacked maize plants was found at 8 hpi (gst23) or 24 hpi (gst1, gst18 and gst24) compared to the control. Investigated Z. mays cultivars formed excessive superoxide anion radicals in response to insect treatments, and the highest overproduction of O2•- was noted 4 or 8 h after infestation, depending on the aphid treatment and maize genotype. Importantly, the Ambrozja variety could be characterized as having more profound increments in the levels of gst transcript abundance and O2•- generation in comparison with the Tasty Sweet genotype.

MicroRNA-133b targets glutathione S-transferase π expression to increase ovarian cancer cell sensitivity to chemotherapy drugs.

PubMed

Chen, Shuo; Jiao, Jin-Wen; Sun, Kai-Xuan; Zong, Zhi-Hong; Zhao, Yang

2015-01-01

Accumulating studies reveal that aberrant microRNA (miRNA) expression can affect the development of chemotherapy drug resistance by modulating the expression of relevant target proteins. The aim of this study was to investigate the role of miR-133b in the development of drug resistance in ovarian cancer cells. We examined the levels of miR-133b expression in ovarian carcinoma tissues and the human ovarian carcinoma cell lines (A2780, A2780/DDP and A2780/Taxol, respectively). We determined the cell viability of these cell lines treated with cisplatin or paclitaxel in the presence or absence of miR-133b or anti-miR-133b transfection using the MTT assay. Reverse transcription polymerase chain reaction and Western blotting were used to assess the mRNA and protein expression levels of two drug-resistance-related genes: glutathione S-transferase (GST)-π and multidrug resistance protein 1 (MDR1). The dual-luciferase reporter assay was used to detect the promoter activity of GST-π in the presence and absence of miR-133b. The expression of miR-133b was significantly lower in primary resistant ovarian carcinomas than in the chemotherapy-sensitive carcinomas (P<0.05), and the same results were found in primary resistant ovarian cell lines (A2780/Taxol and A2780/DDP) compared to the chemotherapy-sensitive cell line (A2780; P<0.05). Following miR-133b transfection, four cell lines showed increased sensitivity to paclitaxel and cisplatin, while anti-miR-133b transfection reduced cell sensitivity to paclitaxel and cisplatin. Dual-luciferase reporter assay showed that miR-133b interacted with the 3'-untranslated region of GST-π. Compared to controls, the mRNA and protein levels of MDR1 and GST-π were downregulated after miR-133b transfection and upregulated after anti-miR-133b transfection. MicroRNA-133b may reduce ovarian cancer drug resistance by silencing the expression of the drug-resistance-related proteins, GST-π and MDR1. In future, the combination of miR-133b with

Size effect of elemental selenium nanoparticles (Nano-Se) at supranutritional levels on selenium accumulation and glutathione S-transferase activity.

PubMed

Peng, Dungeng; Zhang, Jinsong; Liu, Qingliang; Taylor, Ethan Will

2007-10-01

It has been shown that 36 nm Nano-Se has lower toxicity than selenite or selenomethionine, but these forms of selenium (Se) all possess similar ability to increase selenoenzyme levels. The size of nanoparticles plays an important role in their biological activity: as expected, 5-200 nm Nano-Se can directly scavenge free radicals in vitro in a size-dependent fashion. However, in Se-deficient cells and Se-deficient mice, the size effect of Nano-Se on increasing selenoenzymes and liver Se disappears unexpectedly. We hypothesize that under conditions of Se deficiency, the avidity of Se uptake mechanisms may be increased to maintain the biosynthesis of selenoenzymes, which are fundamental for redox homeostasis. This increased avidity may override the potential advantage of small size Nano-Se seen under Se-replete conditions, thereby eliminating the size effect. Once selenoenzymes have been saturated, Se uptake mechanisms may downregulate; accordingly, the size effect of Nano-Se can then reappear. To test this hypothesis, Se-deficient mice were administered either 36 or 90 nm Nano-Se at supranutritional doses, in both a short-term model and a single-dose model. Under these conditions, Nano-Se showed a size effect on Se accumulation and glutathione S-transferase (GST) activity. A size effect of Nano-Se was found in 15 out of 18 total comparisons between sizes at the same dose and time in the two models. Furthermore, the magnitude of the size effect was more prominent on Se accumulation than on GST activity. GST is strictly regulated by transcriptional and translational mechanisms, so its increase in activity normally does not exceed 3-fold. In contrast, the homeostasis of Se accumulation is not as tightly controlled. In the present experiments, GST activity had reached or was approaching saturation, but liver Se was far below saturation. Therefore, our results strongly suggest that the saturation profile of the tested biomarker has an impact on the size effect of Nano

Glutathione S-Transferase Polymorphisms (GSTM1, GSTT1 and GSTP1) and Their Susceptibility to Renal Cell Carcinoma: An Evidence-Based Meta-Analysis

PubMed Central

Deng, Jianping; Deng, Tianxing; Gong, Zhihua; Hao, Ping

2013-01-01

Background The association of the three Glutathione S-transferases (GSTs) polymorphisms (GSTM1, GSTT1 and GSTP1) genotypes with their individual susceptibilities to renal cell carcinoma (RCC) has not been well established. We performed a quantitative meta-analysis to assess the possible associations between the GSTM1, GSTT1 and GSTP1 genotypes and their individual susceptibilities to renal cell carcinoma. Methods We systematically searched the PubMed, CNKI and Embase databases to identify the relevant studies. Finally, 11 eligible studies were selected. The pooled odds ratios (ORs) with their 95% confidence intervals (CIs) were used to assess the association between the GSTs polymorphisms and the risk of RCC. Multiple subgroup analyses and quality assessment of the included studies were performed based on the available information. Results None of the GSTs polymorphisms had a significant association with the RCC risk. Similar results were found in the subgroup analyses, except for the GSTs polymorphisms in the situations described below. The GSTM1 and GSTT1 active genotypes in subjects exposed to pesticides (GSTM1: OR = 3.44; 95% CI, 2.04–5.80; GSTT1: OR = 2.84; 95% CI, 1.75–4.60), most of the GSTs genotypes in Asian populations (GSTT1: OR = 2.39, 95% CI = 1.63–3.51; GSTP1: Dominant model: OR = 1.50, 95% CI = 1.14–1.99; Additive model: OR = 1.39, 95% CI = 1.12–1.73; AG vs. AA: OR = 1.47, 95% CI = 1.10–1.97; GG vs. AA: OR = 1.82, 95% CI = 1.07–3.09) and the dual null genotype of GSTT1-GSTP1 (OR = 2.84, 95% CI = 1.75–4.60) showed positive associations with the RCC risk. Conclusion Our present study provides evidence that the GSTM1, GSTT1 and GSTP1 polymorphisms are not associated with the development of RCC. However, more case-control studies are needed for further confirmation. PMID:23717494

Genetic polymorphisms of GSTO2, GSTM1, and GSTT1 and risk of gastric cancer.

PubMed

Masoudi, Mohammad; Saadat, Iraj; Omidvari, Shahpour; Saadat, Mostafa

2009-04-01

The glutathione S-transferases (GSTs) are a superfamily of proteins that participates in detoxification. The GSTs were dividing into several classes including omega (GSTO), micro (GSTM) and theta (GSTT) classes. In human GSTO2, GSTM1, and GSTT1 are polymorphic. In order to study whether GSTO2, GSTM1, and GSTT1 polymorphisms are associated with increased gastric cancer risk in Iranian patients, the present case-control study was done. Genomic DNA was extracted from peripheral blood of 67 gastric cancer patients and 134 control subjects. The genotyping was performed using PCR-based method. The possible association of gastric cancer with the GSTO2 N142D polymorphism was estimated with assuming additive, dominant, and recessive effect of the variant 142D allele. To investigate whether profiles of GST genotypes are associated with the risk of gastric cancer, we used unconditional logistic regression analysis. The GSTO2 142D allele in additive, dominant and recessive models was not associated with the risk. Because GSTM1, GSTT1, and GSTO2 genes belong to low-penetrance genes which might be involved in the carcinogenesis, patients and controls without family of cancer in first-degree relatives were also analyzes separately. To investigate whether profiles of GST genotypes are associated with the risk of gastric cancer, we used unconditional logistic regression analysis with GSTM1, GSTT1, and GSTO2 genotypes as predictor factors. The GSTO2 DD genotype was associated with decreased risk as compared to GSTO2 NN genotype (OR = 0.21, 95% CI: 0.05-0.92, P = 0.038). Present findings show that GSTO2 DD genotype decreases the risk of gastric cancer in individuals without history of cancer in their first-degree relatives.

An alternative easy method for antibody purification and analysis of protein-protein interaction using GST fusion proteins immobilized onto glutathione-agarose.

PubMed

Zalazar, L; Alonso, C A I; De Castro, R E; Cesari, A

2014-01-01

Immobilization of small proteins designed to perform protein-protein assays can be a difficult task. Often, the modification of reactive residues necessary for the interaction between the immobilized protein and the matrix compromises the interaction between the protein and its target. In these cases, glutathione-S-transferase (GST) is a valuable tag providing a long arm that makes the bait protein accessible to the mobile flow phase of the chromatography. In the present report, we used a GST fusion version of the 8-kDa protein serine protease inhibitor Kazal-type 3 (SPINK3) as the bait to purify anti-SPINK3 antibodies from a rabbit crude serum. The protocol for immobilization of GST-SPINK3 to glutathione-agarose beads was modified from previously reported protocols by using an alternative bifunctional cross-linker (dithiobis(succinimidyl propionate)) in a very simple procedure and by using simple buffers under physiological conditions. We concluded that the immobilized protein remained bound to the column after elution with low pH, allowing the reuse of the column for alternative uses, such as screening for other protein-protein interactions using SPINK3 as the bait.

Identification and expression profiles of nine glutathione S-transferase genes from the important rice phloem sap-sucker and virus vector Laodelphax striatellus (Fallén) (Hemiptera: Delphacidae).

PubMed

Zhou, Wen-Wu; Li, Xi-Wang; Quan, Yin-Hua; Cheng, Jiaan; Zhang, Chuan-Xi; Gurr, Geoff; Zhu, Zeng-Rong

2012-09-01

Glutathione S-transferases (GSTs) have received considerable attention in insects for their roles in insecticide resistance. Laodelphax striatellus (Fallén) is a serious rice pest. L. striatellus outbreaks occur frequently throughout eastern Asia. A key problem in controlling this pest is its rapid adaptation to numerous insecticides. In this research, nine cDNAs encoding GSTs in L. striatellus were cloned and characterised. The cloned GSTs of L. striatellus belonged to six cytosolic classes and a microsomal subgroup. Exposure to sublethal concentrations of each of the six insecticides, DDT, chlorpyrifos, fipronil, imidacloprid, buprofezin and beta-cypermethrin, quickly induced (6 h) up-expression of LsGSTe1. The expression of LsGSTs2 was increased by chlorpyrifos, fipronil and beta-cypermethrin. Furthermore, exposure of L. striatellus to fipronil, imidacloprid, buprofezin and beta-cypermethrin increased the expression of the LsGSTm gene after 24 or 48 h. This work is the first identification of GST genes from different GST groups in Auchenorrhyncha species and their induction characteristics with insecticide types and time. The elevated expression of GST genes induced by insecticides might be related to the enhanced tolerance of this insect to insecticides and xenobiotics. Copyright © 2012 Society of Chemical Industry.

Polymorphisms in GSTM1, GSTT1, GSTP1, and GSTM3 genes and breast cancer risk in northeastern Mexico.

PubMed

Jaramillo-Rangel, G; Ortega-Martínez, M; Cerda-Flores, R M; Barrera-Saldaña, H A

2015-06-11

Glutathione S-transferases (GSTs) are a family of phase II metabolizing enzymes involved in carcinogen detoxification and the metabolism of various bioactive compounds. Several genes that code for these enzymes are polymorphic in an ethnicity-dependent manner, with particular genotypes previously associated with an increased risk of breast cancer. The purpose of this study was to determine the frequencies of polymorphisms in the genes GSTM1, GSTT1, GSTP1, and GSTM3 and to investigate whether an association exists between these genes and breast cancer risk in subjects from northeastern Mexico. Genotypes were determined for 243 women with histologically confirmed breast cancer and 118 control subjects. Gene polymorphisms were analyzed using a DNA microarray. We found an increased breast cancer risk associated with the GSTM1 gene deletion polymorphism (OR = 2.19; 95%CI = 1.50-3.21; P = 0.001). No associations between the GSTT1, GSTP1, and GSTM3 genotypes and neoplasia risk were observed. In conclusion, we determined the genotype distribution of GST polymorphisms in control subjects and breast cancer patients from northeastern Mexico. The GSTM1 null genotype was associated with breast cancer risk. Our findings may be used to individualize breast cancer screening and therapeutic intervention in our population, which displays ethnic characteristics that differentiate it from other populations in Mexico.

Functional characterisation of ganglioside-induced differentiation-associated protein 1 as a glutathione transferase.

PubMed

Shield, Alison J; Murray, Tracy P; Board, Philip G

2006-09-08

Mutations in the ganglioside-induced differentiation-associated protein 1 (GDAP1) gene have been linked with Charcot-Marie-Tooth (CMT) disease. This protein, and its paralogue GDAP1L1, appear to be structurally related to the cytosolic glutathione S-transferases (GST) including an N-terminal thioredoxin fold domain with conserved active site residues. The specific function, of GDAP1 remains unknown. To further characterise their structure and function we purified recombinant human GDAP1 and GDAP1L1 proteins using bacterial expression and immobilised metal affinity chromatography. Like other cytosolic GSTs, GDAP1 protein has a dimeric structure. Although the full-length proteins were largely insoluble, the deletion of a proposed C-terminal transmembrane domain allowed the preparation of soluble protein. The purified proteins were assayed for glutathione-dependent activity against a library of 'prototypic' GST substrates. No evidence of glutathione-dependent activity or an ability to bind glutathione immobilised on agarose was found.

Synthesis and biological evaluation of 2-substituted-5-(4-nitrophenylsulfonamido)benzoxazoles as human GST P1-1 inhibitors, and description of the binding site features.

PubMed

Ertan-Bolelli, Tuğba; Musdal, Yaman; Bolelli, Kayhan; Yilmaz, Serap; Aksoy, Yasemin; Yildiz, Ilkay; Aki-Yalcin, Esin; Yalcin, Ismail

2014-05-01

Glutathione-S-transferases (GSTs) are enzymes involved in cellular detoxification by catalyzing the nucleophilic attack of glutathione (GSH) on the electrophilic center of numerous of toxic compounds and xenobiotics, including chemotherapeutic drugs. Human GST P1-1, which is known as the most prevalent isoform of the mammalian cytosolic GSTs, is overexpressed in many cancers and contributes to multidrug resistance by directly conjugating to chemotherapeutics. It is suggested that this resistance is related to the high expression of GST P1-1 in cancers, thereby contributing to resistance to chemotherapy. In addition, GSTs exhibit sulfonamidase activity, thereby catalyzing the GSH-mediated hydrolysis of sulfonamide bonds. Such reactions are of interest as potential tumor-directed prodrug activation strategies. Herein we report the design and synthesis of some novel sulfonamide-containing benzoxazoles, which are able to inhibit human GST P1-1. Among the tested compounds, 2-(4-chlorobenzyl)-5-(4-nitrophenylsulfonamido)benzoxazole (5 f) was found as the most active hGST P1-1 inhibitor, with an IC50 value of 10.2 μM, showing potency similar to that of the reference drug ethacrynic acid. Molecular docking studies performed with CDocker revealed that the newly synthesized 2-substituted-5-(4-nitrophenylsulfonamido)benzoxazoles act as catalytic inhibitors of hGST P1-1 by binding to the H-site and generating conjugates with GSH to form S-(4-nitrophenyl)GSH (GS-BN complex) via nucleophilic aromatic substitution reaction. The 4-nitrobenzenesulfonamido moiety at position 5 of the benzoxazole ring is essential for binding to the H-site and for the formation of the GST-mediated GSH conjugate. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Rat lung glutathione S-transferases. Evidence for two distinct types of 22000-Mr subunits.

PubMed Central

Singh, S V; Partridge, C A; Awasthi, Y C

1984-01-01

Two immunologically distinct types of 22000-Mr subunits are present in rat lung glutathione S-transferases. One of these subunits is probably similar to Ya subunits of rat liver glutathione S-transferases, whereas the other subunit Ya' is immunologically distinct. Glutathione S-transferase II (pI7.2) of rat lung is a heterodimer (YaYa') of these subunits, and glutathione S-transferase VI (pI4.8) of rat lung is a homodimer of Ya' subunits. On hybridization in vitro of the subunits of glutathione S-transferase II of rat lung three active dimers having pI values 9.4, 7.2 and 4.8 are obtained. Immunological properties and substrate specificities indicate that the hybridized enzymes having pI7.2 and 4.8 correspond to glutathione S-transferases II and VI of rat lung respectively. Images Fig. 1. Fig. 5. PMID:6433888

Expression Profiling of Selected Glutathione Transferase Genes in Zea mays (L.) Seedlings Infested with Cereal Aphids

PubMed Central

Sytykiewicz, Hubert; Chrzanowski, Grzegorz; Czerniewicz, Paweł; Sprawka, Iwona; Łukasik, Iwona; Goławska, Sylwia; Sempruch, Cezary

2014-01-01

The purpose of this report was to evaluate the expression patterns of selected glutathione transferase genes (gst1, gst18, gst23 and gst24) in the tissues of two maize (Zea mays L.) varieties (relatively resistant Ambrozja and susceptible Tasty Sweet) that were colonized with oligophagous bird cherry-oat aphid (Rhopalosiphum padi L.) or monophagous grain aphid (Sitobion avenae L.). Simultaneously, insect-triggered generation of superoxide anion radicals (O2 •−) in infested Z. mays plants was monitored. Quantified parameters were measured at 1, 2, 4, 8, 24, 48 and 72 h post-initial aphid infestation (hpi) in relation to the non-infested control seedlings. Significant increases in gst transcript amounts were recorded in aphid-stressed plants in comparison to the control seedlings. Maximal enhancement in the expression of the gst genes in aphid-attacked maize plants was found at 8 hpi (gst23) or 24 hpi (gst1, gst18 and gst24) compared to the control. Investigated Z. mays cultivars formed excessive superoxide anion radicals in response to insect treatments, and the highest overproduction of O2 •− was noted 4 or 8 h after infestation, depending on the aphid treatment and maize genotype. Importantly, the Ambrozja variety could be characterized as having more profound increments in the levels of gst transcript abundance and O2 •− generation in comparison with the Tasty Sweet genotype. PMID:25365518

Elevated Levels of Urinary 8-Hydroxy-2′-deoxyguanosine, Lymphocytic Micronuclei, and Serum Glutathione S-Transferase in Workers Exposed to Coke Oven Emissions

PubMed Central

Liu, Ai-Lin; Lu, Wen-Qing; Wang, Zeng-Zhen; Chen, Wei-Hong; Lu, Wen-Hong; Yuan, Jing; Nan, Pei-Hong; Sun, Jian-Ya; Zou, Ya-Lin; Zhou, Li-Hong; Zhang, Chi; Wu, Tang-Chun

2006-01-01

To investigate associations among occupational exposure to coke oven emissions (COEs), oxidative stress, cytogenotoxic effects, change in the metabolizing enzyme glutathione S-transferase (GST), and internal levels of polycyclic aromatic hydrocarbons (PAHs) in coke oven workers, we recruited 47 male coke oven workers and 31 male control subjects from a coke oven plant in northern China. We measured the levels of 1-hydroxypyrene (1-OHP) and 8-hydroxy-2′-deoxyguanosine (8-OHdG) in urine, micronucleated binucleated cells (BNMNs) in peripheral blood lymphocyte, and GST in serum. Our results showed that the group exposed to COEs had significantly increased levels of 1-OHP [median 5.7; interquartile range (IQR), 1.4–12.0 μmol/mol creatinine] compared with the control group (3; 0.5–6.4 μmol/mol creatinine). In addition, the median levels (IQR) of 8-OHdG, BNMNs, and GST were markedly increased in the exposed [1.9 (1.4–15.4) μmol/mol creatinine; 6 (2–8) per thousand; 22.1 (14.9–31.2) U/L, respectively] compared with controls [1.3 (1.0–4.0) μmol/mol creatinine, 2 (0–4) per thousand; and 13.1 (9.5–16.7) U/L, respectively]. These results appeared to be modified by smoking. However, multivariate logistic regression analysis revealed that exposure to COEs had the highest odds ratio among variables analyzed and that smoking was not a significant confounder of the levels of studied biomarkers. Overall, the present findings suggest that COE exposure led to increased internal PAH burden, genetic damage, oxidative stress, and GST activity. The consequences of the changes in these biomarkers, such as risk of cancer, warrant further investigations. PMID:16675419

The characterization of cytosolic glutathione transferase from four species of sea turtles: loggerhead (Caretta caretta), green (Chelonia mydas), olive ridley (Lepidochelys olivacea), and hawksbill (Eretmochelys imbricata).

PubMed

Richardson, Kristine L; Gold-Bouchot, Gerardo; Schlenk, Daniel

2009-08-01

Glutathione s-transferases (GST) play a critical role in the detoxification of exogenous and endogenous electrophiles, as well as the products of oxidative stress. As compared to mammals, GST activity has not been extensively characterized in reptiles. Throughout the globe, most sea turtle populations face the risk of extinction. Of the natural and anthropogenic threats to sea turtles, the effects of environmental chemicals and related biochemical mechanisms, such as GST catalyzed detoxification, are probably the least understood. In the present study, GST activity was characterized in four species of sea turtles with varied life histories and feeding strategies: loggerhead (Caretta caretta), green (Chelonia mydas), olive ridley (Lepidochelys olivacea), and hawksbill (Eretmochelys imbricata). Although similar GST kinetics was observed between species, rates of catalytic activities using class-specific substrates show inter- and intra-species variation. GST from the spongivorous hawksbill sea turtle shows 3-4.5 fold higher activity with the substrate 4-nitrobenzylchloride than the other 3 species. GST from the herbivorous green sea turtle shows 3 fold higher activity with the substrate ethacrynic acid than the carnivorous olive ridley sea turtle. The results of this study may provide insight into differences in biotransformation potential in the four species of sea turtles and the possible health impacts of contaminant biotransformation by sea turtles.

Resonance energy transfer between sites in rat liver glutathione S-transferase, 1-1, selectively modified at cysteine-17 and cysteine-111.

PubMed

Hu, L; Colman, R F

1997-02-18

Monobromobimane (mBBr) can label both Cys111 and Cys17 of rat liver glutathione S-transferase, 1-1 (GST 1-1). However, selective modification of Cys111 was achieved by the maleimide-based sulfhydryl reagents N-ethylmaleimide (NEM) and fluorescein 5-maleimide (NFM). Incubation of GST 1-1 with 5 mM NEM for 30 min at pH 7.5 and 25 degrees C leads to the formation of modified enzyme with 92% residual activity toward 1-chloro-2,4-dinitrobenzene and completely blocks Cys111 from subsequent reaction with either NFM or mBBr. Reaction of GST 1-1 with 0.2 mM NFM under the same conditions affords a modified enzyme with only 14% residual activity even though NFM and NEM target the same Cys111. The results indicate that when the bulky fluorescein is covalently bound to Cys111, the ligand projects into both the xenobiotic binding site and the glutathione site. After NEM or NFM modification of GST 1-1, the enzyme was further modified by monobromobimane at Cys17 with loss of activity. Together with the only tryptophan (Trp20), fluorescein linked to Cys111 and bimane to Cys17 provide three fluorescent probes to study the solution structure of GST 1-1. Fluorescence spectral analysis suggests that Trp20 and bimane linked to Cys17 are located in a relatively hydrophobic environment, while fluorescein linked to Cys111 is located in a charged environment. These fluorescent probes constitute three sets of donor-acceptor pairs for the measurement of fluorescence energy transfer, and distances calculated from such measurements are 20 A between Trp20 and bimane at Cys17, 19 A between Trp20 and fluorescein at Cys111, and < 22 A between bimane at Cys17 and fluorescein at Cys111. Molecular modeling studies indicate that fluorescein lies between the two subunits, is surrounded by charged residues, and is extended into the xenobiotic binding site. They also suggest that mBBr must approach from the dimer interface in order to reach the reaction site at Cys17.

Nuclear factor erythroid-derived 2-related factor 2 activates glutathione S-transferase expression in the midgut of Spodoptera litura (Lepidoptera: Noctuidae) in response to phytochemicals and insecticides.

PubMed

Chen, S; Lu, M; Zhang, N; Zou, X; Mo, M; Zheng, S

2018-05-10

Detoxication enzymes play an important role in insect resistance to xenobiotics such as insecticides and phytochemicals. We studied the pathway for activating the expression of glutathione S-transferases (GSTs) in response to selected xenobiotics. An assay of the promoter activity of GST epsilon 1 (Slgste1) of Spodoptera litura led to the discovery of a cis-regulating element. An antioxidant response element was activated in response to indole-3-carbinol (I3C) and chlorpyrifos (CPF) and was able to bind with the xenobiotic sensor protein nuclear factor erythroid-derived 2-related factor 2 (SlNrf2). SlNrf2 and Slgste1 were responsive to reactive oxygen species induced by I3C and CPF in a S. litura cell line, as well as in S. litura midguts. SlNrf2 RNA interference (RNAi) reduced the message RNA levels of Slgste1 and the peroxidase activity of GSTs in response to I3C, xanthotoxin, CPF and deltamethrin. SlNrf2 RNAi and inhibitor treatment of GST activity decreased the viability of I3C-treated cells. These results indicate that SlNrf2 activates the expression of GSTs in response to oxidative stresses caused by exposure to xenobiotics. © 2018 The Royal Entomological Society.

GLUTATHIONE S-TRANSFERASE-MEDIATED METABOLISM OF BROMODICHLOROMETHANE

EPA Science Inventory

GLUTATHIONE s-TRANSFERASE-MEDIATED METABOLISM OF BROMODICHLOROMETHANE. M K Ross1 and R A Pegram2. 1Curriculum in Toxicology, University of North Carolina at Chapel Hill; 2Experimental Toxicology Division, NHEERL/ORD, United States Environmental Protection Agency, Research Triangl...

Peroxiredoxin 6 homodimerization and heterodimerization with glutathione S-transferase pi are required for its peroxidase but not phospholipase A2 activity.

PubMed

Zhou, Suiping; Sorokina, Elena M; Harper, Sandra; Li, Haitao; Ralat, Luis; Dodia, Chandra; Speicher, David W; Feinstein, Sheldon I; Fisher, Aron B

2016-05-01

Peroxiredoxin 6 (Prdx6) is a unique 1-Cys member of the peroxiredoxin family with both GSH peroxidase and phospholipase A2 (PLA2) activities. It is highly expressed in the lung where it plays an important role in antioxidant defense and lung surfactant metabolism. Glutathionylation of Prdx6 mediated by its heterodimerization with GSH S-transferase π (πGST) is required for its peroxidatic catalytic cycle. Recombinant human Prdx6 crystallizes as a homodimer and sedimentation equilibrium analysis confirmed that this protein exists as a high affinity dimer in solution. Based on measurement of molecular mass, dimeric Prdx6 that was oxidized to the sulfenic acid formed a sulfenylamide during storage. After examination of the dimer interface in the crystal structure, we postulated that the hydrophobic amino acids L145 and L148 play an important role in homodimerization of Prdx6 as well as in its heterodimerization with πGST. Oxidation of Prdx6 also was required for its heterodimerization. Sedimentation equilibrium analysis and the Duolink proximity ligation assay following mutation of the L145 and L148 residues of Prdx6 to Glu indicated greatly decreased dimerization propensity reflecting the loss of hydrophobic interactions between the protein monomers. Peroxidase activity was markedly reduced by mutation at either of the Leu sites and was essentially abolished by the double mutation, while PLA2 activity was unaffected. Decreased peroxidase activity following mutation of the interfacial leucines presumably is mediated via impaired heterodimerization of Prdx6 with πGST that is required for reduction and re-activation of the oxidized enzyme. Copyright © 2016 Elsevier Inc. All rights reserved.

Reduced Anthocyanins in Petioles codes for a GST anthocyanin transporter that is essential for the foliage and fruit coloration in strawberry.

PubMed

Luo, Huifeng; Dai, Cheng; Li, Yongping; Feng, Jia; Liu, Zhongchi; Kang, Chunying

2018-04-27

The red color of the foliage and fruit in strawberry comes from anthocyanins stored in the vacuole; however, how this anthocyanin accumulation is regulated remains unclear. A reduced anthocyanin in petioles (rap) mutant was identified in an N-ethyl-N-nitrosourea (ENU) mutagenized population of YW5AF7, a white-fruited variety of the wild strawberry Fragaria vesca. The causative mutation was identified to be a premature stop codon in a glutathione S-transferase (GST) gene. In addition to the foliage coloration, RAP also mediates fruit pigmentation and acts downstream of the fruit-specific transcription factor FvMYB10. Among all eight GST genes in the same subfamily, RAP is most abundantly expressed in the ripening fruit. Expression analysis and transient expression assays demonstrated that RAP is the principal transporter of anthocyanins among the paralogs. Moreover, domain-swap experiments showed that both the N- and C-terminals of RAP are essential for the binding capability of anthocyanins. In addition, transient knock-down of RAP resulted in reduced fruit coloration in cultivated strawberry. Collectively, our results demonstrate that RAP encodes the principal GST transporter of anthocyanins in the strawberry foliage and fruit, and it could be modified to alter the fruit color in strawberry.

[GST genes expression as prognostic factor in papillary thyroid cancer].

PubMed

Gonçalves, Antonio Jose; Monte, Osmar; Morari, Eliane Cristina; Ward, Laura Sterian; Nakasako, Diana Shimoda; Nieto, Juliana; Nakai, Marianne Yumi

2009-01-01

Analyze the relationship between the AMES classification and molecular factors from Glutation-S-Transferase System, specifically the GSTT1 and GSTM1 in patients with well differentiated thyroid cancer. Samples of thyroid tissue of 66 patients with papillary thyroid carcinoma were obtained (53 women and 13 men). Patients were divided in two groups (high and low risk) according to the AMES classification. In each group, presence of the null genotype of both GST enzymes system was studied. These results were compared with the AMES classification. Samples were obtained in the operating room immediately after thyroidectomy, placed in cryotubes, immersed in liquid nitrogen and stored in a freezer at -80 masculineC. DNA of this enzymes was extracted by the fenol-cloroformium method. There were 17 high risk patients and 49 low risk patients. The null genotype of the high risk group was 5.8% and in the other group was 6.1%. There was no relationship between absence of genes GSTT1 and GSTM1 and prognosis of the papillary thyroid carcinoma when compared to the AMES classifications.

Associations between glutathione S-transferase pi Ile105Val and glyoxylate aminotransferase Pro11Leu and Ile340Met polymorphisms and early-onset oxaliplatin-induced neuropathy.

PubMed

Kanai, Masashi; Yoshioka, Akira; Tanaka, Shiro; Nagayama, Satoshi; Matsumoto, Shigemi; Nishimura, Takafumi; Niimi, Miyuki; Teramukai, Satoshi; Takahashi, Ryo; Mori, Yukiko; Kitano, Toshiyuki; Ishiguro, Hiroshi; Yanagihara, Kazuhiro; Chiba, Tsutomu; Fukushima, Masanori; Matsuda, Fumihiko

2010-04-01

Although the risk of oxaliplatin-induced neuropathy depends on cumulative oxaliplatin dose, susceptibility to this adverse event differs greatly among patients. In this study, we investigated the associations between oxaliplatin-induced neuropathy and the following polymorphisms: glutathione S-transferase pi (GSTP1) Ile(105)Val, and glyoxylate aminotransferase (AGXT) Pro(11)Leu and AGXT Ile(340)Met. Eighty-two Japanese patients with histologically confirmed colorectal cancer who received at least six cycles of the modified FOLFOX6 (m-FOLFOX6) regimen were enrolled. To minimize differences in cumulative oxaliplatin dose between patients, oxaliplatin-induced neuropathy was evaluated using an oxaliplatin-specific scale during the 2-week period after completion of the sixth cycle of treatment. Forty-four patients developed grade 2/3 oxaliplatin-induced neuropathy. There were more patients carrying at least one GSTP1(105)Val allele among the group with grade 2/3 neuropathy (18/44, 41%) than among the group with grade 1 neuropathy (9/38, 24%), although the difference was not statistically significant (P=0.098). There were similar numbers of patients carrying at least one AGXT(105)Met allele in the grade 2/3 neuropathy (7/44, 16%) and grade 1 neuropathy groups (5/38, 13%; P=0.725). The AGXT(11)Leu allele was not found in any of our patients or controls. We found no significant association between oxaliplatin-induced neuropathy and the GSTP1 Ile(105)Val and AGXT Ile(340)Met polymorphisms. Given that no AGXT(11)Leu allele was found among our study population (n=177), evaluating this polymorphism in Japanese patients in future studies is likely to be uninformative.

Molecular cloning, biochemical characterization, and expression analysis of two glutathione S-transferase paralogs from the big-belly seahorse (Hippocampus abdominalis).

PubMed

Tharuka, M D Neranjan; Bathige, S D N K; Lee, Jehee

2017-12-01

Glutathione S-transferases (GSTs, EC 2.5.1.18) are important Phase II detoxifying enzymes that catalyze hydrophobic, electrophilic xenobiotic substance with the conjugation of reduced glutathione (GSH). In this study, GSTμ and GSTρ paralogs of GST in the big belly seahorse (Hippocampus abdominalis; HaGSTρ, HaGSTμ) were biochemically, molecularly, functionally characterized to determine their detoxification range and protective capacities upon different pathogenic stresses. HaGSTρ and HaGSTμ are composed of coding sequences of 681bp and 654bp, which encode proteins 225 and 217 amino acids, with predicted molecular masses of 26.06kDa and 25.74kDa respectively. Sequence analysis revealed that both HaGSTs comprise the characteristic GSH-binding site in the thioredoxin-like N-terminal domain and substrate binding site in the C-terminal domain. The recombinant HaGSTρ and HaGSTμ proteins catalyzed the model GST substrate 1-chloro-2, 4-dinitrobenzene (CDNB). Enzyme kinetic analysis revealed different K m and V max values for each rHaGST, suggesting that they have different conjugation rates. The optimum conditions (pH, temperature) and inhibitory assays of each protein demonstrated different optimal ranges. However, HaGSTμ was highly expressed in the ovary and gill, whereas HaGSTρ was highly expressed in the gill and pouch. mRNA expression of HaGSTρ and HaGSTμ was significantly elevated upon lipopolysaccharide, Poly (I:C), and Edwardsiella tarda challenges in liver and in blood cells as well as with Streptococcus iniae challenge in blood cells. From these collective experimental results, we propose that HaGSTρ and HaGSTμ are effective in detoxifying xenobiotic toxic agents, and importantly, their mRNA expression could be stimulated by immunological stress signals in the aquatic environment. Copyright © 2017 Elsevier Inc. All rights reserved.

Nuclear translocation of glutathione S-transferase π is mediated by a non-classical localization signal.

PubMed

Kawakatsu, Miho; Goto, Shinji; Yoshida, Takako; Urata, Yoshishige; Li, Tao-Sheng

2011-08-12

Glutathione S-transferase π (GSTπ), a member of the GST family of multifunctional enzymes, is highly expressed in human placenta and involved in the protection of cellular components against electrophilic compounds or oxidative stress. We have recently found that GSTπ is expressed in the cytoplasm, mitochondria, and nucleus in some cancer cells, and that the nuclear expression of GSTπ appears to correlate with resistance to anti-cancer drugs. Although the mitochondrial targeting signal of GSTπ was previously identified in the amino-terminal region, the mechanism of nuclear translocation remains completely unknown. In this study, we find that the region of GSTπ195-208 is critical for nuclear translocation, which is mediated by a novel and non-classical nuclear localization signal. In addition, using an in vitro transport assay, we demonstrate that the nuclear translocation of GSTπ depends on the cytosolic extract and ATP. Although further experiments are needed to understand in depth the precise mechanism of nuclear translocation of GSTπ, our results may help to establish more efficient anti-cancer therapy, especially with respect to resistance to anti-cancer drugs. Copyright © 2011 Elsevier Inc. All rights reserved.

Glutathione S-transferase M1 polymorphism and endometriosis susceptibility: a meta-analysis.

PubMed

Li, H; Zhang, Y

2015-02-01

Many studies have investigated the association between glutathione S-transferase M1 (GSTM1) null genotype and the risk of endometriosis. However, the effect of the GSTM1 null genotype on endometriosis is still unclear because of apparent inconsistencies among those studies. A meta-analysis was performed to characterize the relationship more accurately. PubMed, Embase, and Web of Science were searched. To derive a more precise estimation of the relationship, a meta-analysis was performed. We estimated the summary odds ratio (OR) with a 95% confidence interval (95% CI) to assess the association. Up to 24 case-control studies with 2,684 endometriosis cases and 3,119 control cases were included into this meta-analysis. Meta-analysis of the 24 studies showed that GSTM1 null genotype was associated with the risk of endometriosis (random effects OR=1.66, 95% CI 1.23 to 2.24). In the subgroup analysis by ethnicity, increased risks were found for both Caucasians (OR=1.26, 95% CI 1.04-1.51) and Asians (OR=1.28, 95% CI 1.06-1.55). No evidence of publication bias was observed. In conclusion, this meta-analysis suggests that the GSTM1 null genotype increases the overall risk of endometriosis. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

Disruption of Smad-dependent signaling for growth of GST-P-positive lesions from the early stage in a rat two-stage hepatocarcinogenesis model

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ichimura, Ryohei, E-mail: red0828@hotmail.co.j; Mizukami, Sayaka, E-mail: non_sugar_life@hotmail.co.j; Takahashi, Miwa, E-mail: mtakahashi@nihs.go.j

2010-08-01

To clarify the involvement of signaling of transforming growth factor (TGF)-{beta} during the hepatocarcinogenesis, the immunohistochemical distribution of related molecules was analyzed in relation with liver cell lesions expressing glutathione S-transferase placental form (GST-P) during liver tumor promotion by fenbendazole, phenobarbital, piperonyl butoxide, or thioacetamide, using rats. Our study focused on early-stage promotion (6 weeks after starting promotion) and late-stage promotion (57 weeks after starting promotion). With regard to Smad-dependent signaling, cytoplasmic accumulation of phosphorylated Smad (phospho-Smad)-2/3 - identified as Smad3 by later immunoblot analysis - increased in the subpopulation of GST-P{sup +} foci, while Smad4, a nuclear transporter ofmore » Smad2/3, decreased during early-stage promotion. By late-stage promotion, GST-P{sup +} lesions lacking phospho-Smad2/3 had increased in accordance with lesion development from foci to carcinomas, while Smad4 largely disappeared in most proliferative lesions. With regard to Smad-independent mitogen-activated protein kinases, GST-P{sup +} foci that co-expressed phospho-p38 mitogen-activated protein kinase increased during early-stage promotion; however, p38-downstream phospho-activating transcriptional factor (ATF)-2, ATF3, and phospho-c-Myc, were inversely downregulated without relation to promotion. By late-stage promotion, proliferative lesions downregulated phospho-ATF2 and phospho-c-Myc along with lesion development, as with downregulation of phospho-p38 in all lesions. These results suggest that from the early stages, carcinogenic processes were facilitated by disruption of tumor suppressor functions of Smad-dependent signaling, while Smad-independent activation of p38 was an early-stage phenomenon. GST-P{sup -} foci induced by promotion with agonists of peroxisome proliferator-activated receptor-{alpha} did not change Smad expression, suggesting an aberration in the Smad

8-oxo-7,8-dihydro-2'-deoxyguanosine as a biomarker of oxidative damage in oesophageal cancer patients: lack of association with antioxidant vitamins and polymorphism of hOGG1 and GST

PubMed Central

2010-01-01

Background The present report was designed to investigate the origins of elevated oxidative stress measured in cancer patients in our previous work related to a case-control study (17 cases, 43 controls) on oesophageal cancers. The aim was to characterize the relationship between the levels of 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG), antioxidant vitamins and genetic susceptibility. Methods 8-oxodG was analysed in peripheral blood mononuclear cells (PBMCs) by High Performance Liquid Chromatography with Electrochemical Detection (HPLC-ED). Analysis of gene polymorphisms in GSTM1 and GSTT1 was performed by multiplex PCR and in GSTP1 and hOGG1 by a PCR-RFLP method. Reversed-phase HPLC with UV detection at 294 nm was used to measure vitamins A and E in serum from the same blood samples. Results We observed that in our combined population (cases and control, n = 60), there was no statistically significant correlation between the levels of 8-oxodG and (i) the serum concentration of antioxidant vitamins, vitamin A (P = 0.290) or vitamin E (P = 0.813), or (ii) the incidence of the Ser326Cys polymorphic variant (P = 0.637) of the hOGG1 gene. Also, the levels of 8-oxodG were not significantly associated with polymorphisms in metabolite-detoxifying genes, such as GSTs, except for the positive correlation with Val/Val GST P1 allele (P < 0.0001). Conclusions The weakness of our cohort size notwithstanding, vitamins levels in serum and genetic polymorphisms in the hOGG1 or GST genes do not appear to be important modulators of 8-oxodG levels. PMID:21134244

Expression of P-gp, MRP, LRP, GST-π and TopoIIα and intrinsic resistance in human lung cancer cell lines.

PubMed

Wang, Jiarui; Zhang, Jinhui; Zhang, Lichuan; Zhao, Long; Fan, Sufang; Yang, Zhonghai; Gao, Fei; Kong, Ying; Xiao, Gary Guishan; Wang, Qi

2011-11-01

This study aimed to determine the relationship between the endogenous levels of P-glycoprotein (P-gp), multidrug resistance-associated protein (MRP), lung resistance-related protein (LRP), glutathione-s-transferase-π (GST‑π) and topoisomerase IIα (TopoIIα) and intrinsic drug resistance in four human lung cancer cell lines, SK-MES-1, SPCA-1, NCI-H-460 and NCI-H-446, of different histological types. The expression of P-gp, MRP, LRP, GST-π and TopoIIα was measured by immunofluorescence, Western blotting and RT-PCR. Drug resistance to cisplatin, doxorubicin and VP-16 was determined using MTT assays. The correlation between expression of the resistance-related proteins and their roles in the resistance to drugs in these cancer cell lines was analyzed. We found that the endogenous levels of P-gp, MRP, LRP, GST-π and TopoIIα in the four cell lines varied. The level of GST-π in the SK-MES-1 cells was the highest, whereas the level of P-gp in the SPCA-1 cells was the lowest. The chemoresistance to cisplatin, doxorubicin and VP-16 in the four cell lines was different. The SPCA-1 cell line was most resistance to cisplatin; SK-MES-1 was most resistance to VP-16; whereas SK-MES-1 was most sensitive to doxorubicin. There was a positive correlation between GST-π expression and resistance to cisplatin, between TopoIIα expression and resistance to VP-16; and a negative correlation was noted between TopoIIα expression and resistance to doxorubicin. In summary, the endogenous expression of P-gp, MRP, LRP, GST-π and TopoIIα was different in the four human lung cancer cell lines of different histological types, and this variance may be associated with the variation in chemosensitivity to cisplatin, doxorubicin and VP-16. Among the related proteins, GST-π may be useful for the prediction of the intrinsic resistance to cisplatin, whereas TopoIIα may be useful to predict resistance to doxorubicin and VP-16 in human lung cancer cell lines.

Differential Activation of Diverse Glutathione Transferases of Clonorchis sinensis in Response to the Host Bile and Oxidative Stressors

PubMed Central

Bae, Young-An; Ahn, Do-Whan; Lee, Eung-Goo; Kim, Seon-Hee; Cai, Guo-Bin; Kang, Insug; Sohn, Woon-Mok; Kong, Yoon

2013-01-01

trematodes. Interestingly, secretion of a 28 kDa σ-class GST (Cs28σGST3) was significantly affected by the host bile, involving reduced secretion of the 28 kDa species and augmented secretion of Cs28σGST3-related high-molecular-weight 85 kDa protein. Oxidative stressors induced upregulated secretion of 28 kDa Cs28σGST3, but not an 85 kDa species. A secretory 26 kDa μ-class GST (Cs26μGST2) was increased upon treatment with oxidative stressors and bile juice, while another 28 kDa σ-class GST (Cs28σGST1) showed negligible responses. Conclusions/Significance Our results represent the first analysis of the genuine nature of the C. sinensis ESP proteome in the presence of host bile mimicking the natural host environments. The behavioral patterns of migration and maturation of C. sinensis in the bile ducts might contribute to the secretion of copious amounts of diverse GSTs, but a smaller quantity and fewer kinds of cysteine proteases. The Cs28σGST1 and its paralog(s) detoxify endogenous oxidative molecules, while Cs28σGST3 and Cs26μGST2 conjugate xenobiotics/hydrophobic substances in the extracellular environments, which imply that diverse C. sinensis GSTs might have evolved for each of the multiple specialized functions. PMID:23696907

2-Phenethyl Isothiocyanate, Glutathione S-transferase M1 and T1 Polymorphisms, and Detoxification of Volatile Organic Carcinogens and Toxicants in Tobacco Smoke.

PubMed

Yuan, Jian-Min; Murphy, Sharon E; Stepanov, Irina; Wang, Renwei; Carmella, Steven G; Nelson, Heather H; Hatsukami, Dorothy; Hecht, Stephen S

2016-07-01

Cigarette smoke contains relatively large quantities of volatile organic toxicants or carcinogens such as benzene, acrolein, and crotonaldehyde. Among their detoxification products are mercapturic acids formed from glutathione conjugation, catalyzed in part by glutathione S-transferases (GST). A randomized phase II clinical trial with a crossover design was conducted to evaluate the effect of 2-phenethyl isothiocyanate (PEITC), a natural product formed from gluconasturtiin in certain cruciferous vegetables, on the detoxification of benzene, acrolein, and crotonaldehyde in 82 cigarette smokers. Urinary mercapturic acids of benzene, acrolein, and crotonaldehyde at baseline and during treatment were quantified. Overall, oral PEITC supplementation increased the mercapturic acid formed from benzene by 24.6% (P = 0.002) and acrolein by 15.1% (P = 0.005), but had no effect on crotonaldehyde. A remarkably stronger effect was observed among subjects with the null genotype of both GSTM1 and GSTT1: in these individuals, PEITC increased the detoxification metabolite of benzene by 95.4% (P < 0.001), of acrolein by 32.7% (P = 0.034), and of crotonaldehyde by 29.8% (P = 0.006). In contrast, PEITC had no effect on these mercapturic acids in smokers possessing both genes. PEITC had no effect on the urinary oxidative stress biomarker 8-iso-prostaglandin F2α or the inflammation biomarker prostaglandin E2 metabolite. This trial demonstrates an important role of PEITC in detoxification of environmental carcinogens and toxicants which also occur in cigarette smoke. The selective effect of PEITC on detoxification in subjects lacking both GSTM1 and GSTT1 genes supports the epidemiologic findings of stronger protection by dietary isothiocyanates against the development of lung cancer in such individuals. Cancer Prev Res; 9(7); 598-606. ©2016 AACR. ©2016 American Association for Cancer Research.

A glutathione S-transferase gene associated with antioxidant properties isolated from Apis cerana cerana

NASA Astrophysics Data System (ADS)

Liu, Shuchang; Liu, Feng; Jia, Haihong; Yan, Yan; Wang, Hongfang; Guo, Xingqi; Xu, Baohua

2016-06-01

Glutathione S-transferases (GSTs) are an important family of multifunctional enzymes in aerobic organisms. They play a crucial role in the detoxification of exogenous compounds, especially insecticides, and protection against oxidative stress. Most previous studies of GSTs in insects have largely focused on their role in insecticide resistance. Here, we isolated a theta class GST gene designated AccGSTT1 from Apis cerana cerana and aimed to explore its antioxidant and antibacterial attributes. Analyses of homology and phylogenetic relationships suggested that the predicted amino acid sequence of AccGSTT1 shares a high level of identity with the other hymenopteran GSTs and that it was conserved during evolution. Quantitative real-time PCR showed that AccGSTT1 is most highly expressed in adult stages and that the expression profile of this gene is significantly altered in response to various abiotic stresses. These results were confirmed using western blot analysis. Additionally, a disc diffusion assay showed that a recombinant AccGSTT1 protein may be roughly capable of inhibiting bacterial growth and that it reduces the resistance of Escherichia coli cells to multiple adverse stresses. Taken together, these data indicate that AccGSTT1 may play an important role in antioxidant processes under adverse stress conditions.

Polymorphisms of drug-metabolizing enzymes (GST, CYP2B6 and CYP3A) affect the pharmacokinetics of thiotepa and tepa

PubMed Central

Ekhart, Corine; Doodeman, Valerie D; Rodenhuis, Sjoerd; Smits, Paul H M; Beijnen, Jos H; Huitema, Alwin D R

2009-01-01

AIMS Thiotepa is widely used in high-dose chemotherapy. Previous studies have shown relations between exposure and severe organ toxicity. Thiotepa is metabolized by cytochrome P450 and glutathione S-transferase enzymes. Polymorphisms of these enzymes may affect elimination of thiotepa and tepa, its main metabolite. The purpose of this study was to evaluate effects of known allelic variants in CYP2B6, CYP3A4, CYP3A5, GSTA1 and GSTP1 genes on pharmacokinetics of thiotepa and tepa. METHODS White patients (n = 124) received a high-dose regimen consisting of cyclophosphamide, thiotepa and carboplatin as intravenous infusions. Genomic DNA was analysed using polymerase chain reaction and sequencing. Plasma concentrations of thiotepa and tepa were determined using validated GC and LC-MS/MS methods. Relations between allelic variants and elimination pharmacokinetic parameters were evaluated using nonlinear mixed effects modelling (nonmem). RESULTS The polymorphisms CYP2B6 C1459T, CYP3A4*1B, CYP3A5*3, GSTA1 (C-69T, G-52A) and GSTP1 C341T had a significant effect on clearance of thiotepa or tepa. Although significant, most effects were generally not large. Clearance of thiotepa and tepa was predominantly affected by GSTP1 C341T polymorphism, which had a frequency of 9.3%. This polymorphism increased non-inducible thiotepa clearance by 52% [95% confidence interval (CI) 41, 64, P < 0.001] and decreased tepa clearance by 32% (95% CI 29, 35, P < 0.001) in heterozygous patients, which resulted in an increase in combined exposure to thiotepa and tepa of 45% in homozygous patients. CONCLUSIONS This study indicates that the presently evaluated variant alleles explain only a small part of the substantial interindividual variability in thiotepa and tepa pharmacokinetics. Patients homozygous for the GSTP1 C341T allele may have enhanced exposure to thiotepa and tepa. PMID:19076156

Dual protective role for Glutathione S-transferase class pi against VCD-induced ovotoxicity in the rat ovary

DOE Office of Scientific and Technical Information (OSTI.GOV)

Keating, Aileen F.; Sen, Nivedita; Sipes, I. Glenn

2010-09-01

The occupational chemical 4-vinylcyclohexene diepoxide (VCD) selectively destroys ovarian small pre-antral follicles in rats and mice via apoptosis. Detoxification of VCD can occur through glutathione conjugation, catalyzed by glutathione S-transferase (GST) enzymes. Further, GST class pi (GSTp) can negatively regulate JNK activity through protein:protein interactions in extra-ovarian tissues. Dissociation of this protein complex in the face of chemical exposure releases the inhibition of pro-apoptotic JNK. Increased JNK activity during VCD-induced ovotoxicity has been shown in isolated ovarian small pre-antral follicles following in vivo dosing of rats (80 mg/kg/day; 15 days, i.p.). The present study investigated the pattern of ovarian GSTpmore » expression during VCD exposure. Additionally, the effect of VCD on an ovarian GSTp:JNK protein complex was investigated. PND4 F344 rat ovaries were incubated in control medium {+-} VCD (30 {mu}M) for 2-8 days. VCD increased ovarian GSTp mRNA (P < 0.05) relative to control on d4-d8; whereas GSTp protein was increased (P < 0.05) on d6-d8. A GSTp:JNK protein complex was detected by immunoprecipitation and Western blotting in ovarian tissues. Relative to control, the amount of GSTp-bound JNK was increased (P = 0.09), while unbound JNK was decreased (P < 0.05) on d6 of VCD exposure. The VCD-induced decrease in unbound JNK was preceded by a decrease in phosphorylated c-Jun which occurred on d4. These findings are in support of a possible dual protective role for GSTp in the rat ovary, consisting of metabolism of VCD and inhibition of JNK-initiated apoptosis.« less

Gene-environment interactions associated with CYP1A1 MspI and GST polymorphisms and the risk of upper aerodigestive tract cancers in an Indian population.

PubMed

Sam, Soya Sisy; Thomas, Vinod; Reddy, K S; Surianarayanan, Gopalakrishnan; Chandrasekaran, Adithan

2010-06-01

Genetic risk to tobacco related cancers are associated with polymorphisms in CYP1A1 and GST, which are involved in the metabolic activation and detoxification of carcinogens. The genetic variations in these drug-metabolizing enzymes may alter the susceptibility to UADT cancers triggered by environmental exposures. The hospital-based case-control study evaluated the impact of combined CYP1A1 MspI and GST (M1 & T1) polymorphisms among the individuals exposed to environmental risk factors as modulators in the risk of UADT cancers in Tamilians, a population of south India. The unrelated histopathologically confirmed 408 cases and 220 population-based controls matched by age and gender were genotyped for CYP1A1 MspI, GSTM1 and GSTT1 polymorphisms using PCR based methods. To investigate the potential gene-environment interactions, analyses were carried out stratifying by smoking and tobacco chewing status using SPSS software. The combination of genes and environment interactions by stratified analyses revealed significant interactions among the habitual tobacco smokers (CYP1A1 MspI & GSTM1 null: OR 14.06; 95% CI 3.90-50.68, CYP1A1 MspI & GSTT1 null: OR 33.28; 95% CI 4.24-261.19) and tobacco chewers (CYP1A1 MspI & GSTM1 null: OR 20.51; 95% CI 6.77-62.13, CYP1A1 MspI & GSTT1 null: OR 79.35; 95% CI 10.40-605.55) on the multiplicative scale. Our findings have indicated that the individuals polymorphic for CYP1A1 MspI either with GSTM1 null or with GSTT1 null genotypes revealed an increased risk for UADT cancers than that ascribed to a single susceptible gene among the tobacco users in the population [single gene risk among smokers and chewers, respectively, for CYP1A1 MspI (OR 6.43; 95% CI 3.69-11.21); (OR 10.24; 95% CI 5.95-17.60), GSTM1*0 (OR 3.77; 95% CI 1.94-7.37); (OR 7.97 95% CI 4.10-15.76) and GSTT1*0 (OR 6.95 95% CI 2.88-16.77); (OR 25.83 95% CI 7.78-85.76).

Glutathione-S-transferase pi (GSTP1) codon 105 polymorphism is not associated with oxaliplatin efficacy or toxicity in advanced colorectal cancer patients.

PubMed

Kweekel, Dina M; Gelderblom, Hans; Antonini, Ninja F; Van der Straaten, Tahar; Nortier, Johan W R; Punt, Cornelis J A; Guchelaar, Henk-Jan

2009-03-01

Oxaliplatin is detoxified by conjugation to glutathione via the enzyme Glutathione-S-transferase pi (GSTP1). The aim of this study is to investigate the association of GSTP1 Ile105Val genetic polymorphism with oxaliplatin efficacy and toxicity in advanced colorectal cancer (ACC) patients. A total of 91 ACC patients received capecitabine and oxaliplatin (CAPOX) as a part of a multicentre phase-III study of the Dutch Colorectal Cancer Group. Tumour response was evaluated according to RECIST, toxicity was graded using CTC, and GSTP1 Ile105Val was determined by pyrosequencing. Overall survival after CAPOX was similar for patients with the Ile/Ile (11.5 mo), Ile/Val (11.6 mo) and Val/Val (12.6 mo) genotypes (p=0.602). Likewise, there were no statistically significant differences in progression-free survival (p=0.252). Overall grades 3-4 toxicity was not related to genotype (p=0.313). There were no differences in any grade or grades 3-4 neurotoxicity amongst the patients who received > or =500 mg/m(2) of oxaliplatin (p-values of 0.376 and 0.772, respectively). The results of this study indicate that the GSTP1 genotype is not predictive for progression-free survival or overall survival in ACC patients treated with CAPOX. Moreover, overall neurotoxicity and neurotoxicity in patients receiving 500 mg/m(2) of oxaliplatin was not associated with GSTP1 genotype.

Influence of Glutathione and Glutathione S-transferases on DNA Interstrand Cross-Link Formation by 1,2-Bis(methylsulfonyl)-1-(2-chloroethyl)hydrazine, the Active Anticancer Moiety Generated by Laromustine

PubMed Central

2015-01-01

Prodrugs of 1,2-bis(methylsulfonyl)-1-(2-chloroethyl)hydrazine (90CE) are promising anticancer agents. The 90CE moiety is a readily latentiated, short-lived (t1/2 ∼ 30 s) chloroethylating agent that can generate high yields of oxophilic electrophiles responsible for the chloroethylation of the O-6 position of guanine in DNA. These guanine O-6 alkylations are believed to be responsible for the therapeutic effects of 90CE and its prodrugs. Thus, 90CE demonstrates high selectivity toward tumors with diminished levels of O6-alkylguanine-DNA alkyltransferase (MGMT), the resistance protein responsible for O6-alkylguanine repair. The formation of O6-(2-chloroethyl)guanine lesions ultimately leads to the generation of highly cytotoxic 1-(N3-cytosinyl),-2-(N1-guaninyl)ethane DNA interstrand cross-links via N1,O6-ethanoguanine intermediates. The anticancer activity arising from this sequence of reactions is thus identical to this component of the anticancer activity of the clinically used chloroethylnitrosoureas. Herein, we evaluate the ability of glutathione (GSH) and other low molecular weight thiols, as well as GSH coupled with various glutathione S-transferase enzymes (GSTs) to attenuate the final yields of cross-links generated by 90CE when added prior to or immediately following the initial chloroethylation step to determine the major point(s) of interaction. In contrast to studies utilizing BCNU as a chloroethylating agent by others, GSH (or GSH/GST) did not appreciably quench DNA interstrand cross-link precursors. While thiols alone offered little protection at either alkylation step, the GSH/GST couple was able to diminish the initial yields of cross-link precursors. 90CE exhibited a very different GST isoenzyme susceptibility to that reported for BCNU, this could have important implications in the relative resistance of tumor cells to these agents. The protection afforded by GSH/GST was compared to that produced by MGMT. PMID:25012050

Influence of glutathione and glutathione S-transferases on DNA interstrand cross-link formation by 1,2-bis(methylsulfonyl)-1-(2-chloroethyl)hydrazine, the active anticancer moiety generated by laromustine.

PubMed

Penketh, Philip G; Patridge, Eric; Shyam, Krishnamurthy; Baumann, Raymond P; Zhu, Rui; Ishiguro, Kimiko; Sartorelli, Alan C

2014-08-18

Prodrugs of 1,2-bis(methylsulfonyl)-1-(2-chloroethyl)hydrazine (90CE) are promising anticancer agents. The 90CE moiety is a readily latentiated, short-lived (t1/2 ∼ 30 s) chloroethylating agent that can generate high yields of oxophilic electrophiles responsible for the chloroethylation of the O-6 position of guanine in DNA. These guanine O-6 alkylations are believed to be responsible for the therapeutic effects of 90CE and its prodrugs. Thus, 90CE demonstrates high selectivity toward tumors with diminished levels of O(6)-alkylguanine-DNA alkyltransferase (MGMT), the resistance protein responsible for O(6)-alkylguanine repair. The formation of O(6)-(2-chloroethyl)guanine lesions ultimately leads to the generation of highly cytotoxic 1-(N(3)-cytosinyl),-2-(N(1)-guaninyl)ethane DNA interstrand cross-links via N(1),O(6)-ethanoguanine intermediates. The anticancer activity arising from this sequence of reactions is thus identical to this component of the anticancer activity of the clinically used chloroethylnitrosoureas. Herein, we evaluate the ability of glutathione (GSH) and other low molecular weight thiols, as well as GSH coupled with various glutathione S-transferase enzymes (GSTs) to attenuate the final yields of cross-links generated by 90CE when added prior to or immediately following the initial chloroethylation step to determine the major point(s) of interaction. In contrast to studies utilizing BCNU as a chloroethylating agent by others, GSH (or GSH/GST) did not appreciably quench DNA interstrand cross-link precursors. While thiols alone offered little protection at either alkylation step, the GSH/GST couple was able to diminish the initial yields of cross-link precursors. 90CE exhibited a very different GST isoenzyme susceptibility to that reported for BCNU, this could have important implications in the relative resistance of tumor cells to these agents. The protection afforded by GSH/GST was compared to that produced by MGMT.

Cholinesterase and glutathione S-transferase activities of three mollusc species from the NW Portuguese coast in relation to the 'Prestige' oil spill.

PubMed

Tim-Tim, Ana L S; Morgado, Fernando; Moreira, Susana; Rangel, Rui; Nogueira, António J A; Soares, Amadeu M V M; Guilhermino, Lúcia

2009-12-01

In November 2002, the tanker 'Prestige' released about 19,000 tonnes of a heavy fuel oil (no. 6) before sinking with about 58,000 tonnes of its cargo, 135 miles from Cabo Finisterra (Spain). A considerable part of the released fuel oil reached the Galician coast, causing a heavy black tide and an ecological disaster. Although the black tide did not reach the NW coast of Portugal, it is possible that some of the fuel oil or its components also arrived to this area directly through the sea water and/or indirectly through the food chain. Therefore, the aim of this study was to investigate possible changes in two widely used biomarkers, the activity of the enzymes cholinesterases (ChE) and glutathione S-transferases (GST), of three molluscs (Mytilus galloprovincialis, Nucella lapillus and Monodonta lineata) from wild populations of the NW Portuguese coast in relation to the 'Prestige' oil spill. Molluscs were collected seasonally before (autumn 2002) and after (winter 2002/2003), spring and summer 2003) the oil spill at several sites along the Portuguese NW coast. Enzymatic activities determined before the accident were compared with those determined at different times after the oil spill taking into consideration abiotic factors. Information from different parameters was integrated by Redundancy Analysis and Principal Response Curves (PRC). Results show that GST and ChE activities were influenced by abiotic factors. Despite this influence, the results of PRC analysis also suggest that some of the fuel oil reached the NW Portuguese coast changing the patterns of ChE and GST activities of local populations of rocky shore species. Furthermore, the present study highlights the need of long-term monitoring with wild populations to assess both historical and punctual effects of pollution in the marine environment.

Genetic Polymorphisms of Cytochrome P4501A1 (CYP1A1) and Glutathione S-Transferase P1 (GSTP1) and Risk of Hepatocellular Carcinoma Among Chronic Hepatitis C Patients in Egypt.

PubMed

Abo-Hashem, Ekbal M; El-Emshaty, Wafaa M; Farag, Raghda El Sayed; Zakaria, Sahar; Abd El-Aziz, Mohammed; Ghonaim, Azza

2016-10-01

Cytochrome P450 1A1 (CYP1A1) and Glutathione S-transferase P1 (GSTP1) genes are involved in the metabolism of many carcinogens. Polymorphisms in these genes with altered enzyme activity have been reported. The present study evaluated the synergistic effect between CYP1A1 and GSTP1 gene polymorphisms and smoking on development of HCV-related liver disease and hepatocellular carcinoma (HCC). The patients group comprised 40 patients with HCC and 40 patients with liver cirrhosis. The control group comprised 40 healthy subjects having no history of malignancy. The genetic polymorphisms were studied using polymerase chain reaction restriction fragment length polymorphism (PCR RFLP) technique on blood samples. The number of current or former smoker among HCC and cirrhotic patients as well as the median Pack/year of cigarette smoked were significantly higher in HCC and liver cirrhotic patients than in control group. Subjects with CYP1A1 gene variants (m1 and m3) had no significant risk to develop cirrhosis or HCC compared to control group. Individuals carrying the Ile/Val genotype of GSTP1 had a significant increased risk of HCC (OR of 2.2, 95 % CI 1.143-4.261) and had larger tumor size. No significant risk was observed on combining both genes variants or on combining smoking with variants of both genes. In conclusion, the GSTP1 Ile/Val genotype and Val allele are associated with an increased risk of HCC. CYP1A1 and GSTP1 genes variants interaction did not increase the risk of HCC.

Identification and clarification of the role of key active site residues in bacterial glutathione S-transferase zeta/maleylpyruvate isomerase

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fang, Ti; Li, De-Feng; Zhou, Ning-Yi, E-mail: n.zhou@pentium.whiov.ac.cn

2011-07-08

Highlights: {yields} Application of site-directed mutagenesis to probe the active site residues of glutathione-dependent maleylpyruvate isomerase. {yields} Two conserved residues, Arg8 and Arg176, in zeta class glutathione S-transferases are critical for maleylpyruvate orientation and enolization. {yields} Arg109, found exclusively in NagL, participates in k{sub cat} regulation. {yields} The T11A mutant exhibited a significantly decreased K{sub m} value for glutathione with little impact on maleylpyruvate kinetics. {yields} The Thr11 residue appears to have significance in the evolution of glutathione S-transferase classes. -- Abstract: The maleylpyruvate isomerase NagL from Ralstonia sp. strain U2, which has been structurally characterized previously, catalyzes the isomerizationmore » of maleylpyruvate to fumarylpyruvate. It belongs to the class zeta glutathione S-transferases (GSTZs), part of the cytosolic GST family (cGSTs). In this study, site-directed mutagenesis was conducted to probe the functions of 13 putative active site residues. Steady-state kinetic information for mutants in the reduced glutathione (GSH) binding site, suggested that (a) Gln64 and Asp102 interact directly with the glutamyl moiety of glutathione, (b) Gln49 and Gln64 are involved in a potential electron-sharing network that influences the ionization of the GSH thiol. The information also suggests that (c) His38, Asn108 and Arg109 interact with the GSH glycine moiety, (d) His104 has a role in the ionization of the GSH sulfur and the stabilization of the maleyl terminal carboxyl group in the reaction intermediate and (e) Arg110 influences the electron distribution in the active site and therefore the ionization of the GSH thiolate. Kinetic data for mutants altered in the substrate-binding site imply that (a) Arg8 and Arg176 are critical for maleylpyruvate orientation and enolization, and (b) Arg109 (exclusive to NagL) participates in k{sub cat} regulation. Surprisingly, the T11A mutant

Drug-related genetic polymorphisms affecting severe chemotherapy-induced neutropenia in breast cancer patients

PubMed Central

Tsuji, Daiki; Ikeda, Midori; Yamamoto, Keisuke; Nakamori, Harumi; Kim, Yong-Il; Kawasaki, Yohei; Otake, Aki; Yokoi, Mari; Inoue, Kazuyuki; Hirai, Keita; Nakamichi, Hidenori; Tokou, Umi; Shiokawa, Mitsuru; Itoh, Kunihiko

2016-01-01

Abstract Chemotherapy-induced neutropenia (CIN) is one of the major adverse events that necessitate chemotherapy dose reduction. This study aimed to evaluate the association between grade 4 neutropenia and genetic polymorphisms in breast cancer patients. In this genetic polymorphism association study, peripheral blood samples from 100 consecutive breast cancer outpatients, between August 2012 and September 2014, treated with doxorubicin and cyclophosphamide (AC) combination chemotherapy were genotyped for polymorphisms in adenosine triphosphate-binding cassette subfamily B member 1 (ABCB1), cytochrome P450 (CYP) enzyme-coding genes (CYP2B6 and CYP3A5), glutathione S-transferase (GST), and excision repair cross-complementing 1 (ERCC1). Associations between grade 4 neutropenia and genotypes as well as risk factors were examined using multivariate logistic regression. From 100 patients, 32.0% had grade 4 neutropenia. Multivariate logistic regression analysis revealed that ERCC1 118C > T (odds ratio [OR], 3.43; 95% confidence interval [CI], 1.22–9.69; P = 0.020), CYP2B6∗6 (OR, 4.51; 95% CI, 1.21–16.95; P = 0.025), body mass index (BMI) (OR, 6.94; 95% CI, 1.15–41.67; P = 0.035), and baseline white blood cell (WBC) count (OR, 2.99; 95% CI, 1.06–8.40; P = 0.038) were significant predictors of grade 4 neutropenia. ERCC1 and CYP2B6 gene polymorphisms were associated with the extent of grade 4 neutropenia in patients receiving AC chemotherapy. In addition to previously known risk factors, BMI and WBC counts, ERCC1 and CYP2B6 gene polymorphisms were also identified as independent strong predictors of grade 4 neutropenia. PMID:27858847

Conformational stability of pGEX-expressed Schistosoma japonicum glutathione S-transferase: a detoxification enzyme and fusion-protein affinity tag.

PubMed Central

Kaplan, W.; Hüsler, P.; Klump, H.; Erhardt, J.; Sluis-Cremer, N.; Dirr, H.

1997-01-01

A glutathione S-transferase (Sj26GST) from Schistosoma japonicum, which functions in the parasite's Phase II detoxification pathway, is expressed by the Pharmacia pGEX-2T plasmid and is used widely as a fusion-protein affinity tag. It contains all 217 residues of Sj26GST and an additional 9-residue peptide linker with a thrombin cleavage site at its C-terminus. Size-exclusion HPLC (SEC-HPLC) and SDS-PAGE studies indicate that purification of the homodimeric protein under nonreducing conditions results in the reversible formation of significant amounts of 160-kDa and larger aggregates without a loss in catalytic activity. The basis for oxidative aggregation can be ascribed to the high degree of exposure of the four cysteine residues per subunit. The conformational stability of the dimeric protein was studied by urea- and temperature-induced unfolding techniques. Fluorescence-spectroscopy, SEC-HPLC, urea- and temperature-gradient gel electrophoresis, differential scanning microcalorimetry, and enzyme activity were employed to monitor structural and functional changes. The unfolding data indicate the absence of thermodynamically stable intermediates and that the unfolding/refolding transition is a two-state process involving folded native dimer and unfolded monomer. The stability of the protein was found to be dependent on its concentration, with a delta G degree (H2O) = 26.0 +/- 1.7 kcal/mol. The strong relationship observed between the m-value and the size of the protein indicates that the amount of protein surface area exposed to solvent upon unfolding is the major structural determinant for the dependence of the protein's free energy of unfolding on urea concentration. Thermograms obtained by differential scanning microcalorimetry also fitted a two-state unfolding transition model with values of delta Cp = 7,440 J/mol per K, delta H = 950.4 kJ/mol, and delta S = 1,484 J/mol. PMID:9041642

Conformational stability of pGEX-expressed Schistosoma japonicum glutathione S-transferase: a detoxification enzyme and fusion-protein affinity tag.

PubMed

Kaplan, W; Hüsler, P; Klump, H; Erhardt, J; Sluis-Cremer, N; Dirr, H

1997-02-01

A glutathione S-transferase (Sj26GST) from Schistosoma japonicum, which functions in the parasite's Phase II detoxification pathway, is expressed by the Pharmacia pGEX-2T plasmid and is used widely as a fusion-protein affinity tag. It contains all 217 residues of Sj26GST and an additional 9-residue peptide linker with a thrombin cleavage site at its C-terminus. Size-exclusion HPLC (SEC-HPLC) and SDS-PAGE studies indicate that purification of the homodimeric protein under nonreducing conditions results in the reversible formation of significant amounts of 160-kDa and larger aggregates without a loss in catalytic activity. The basis for oxidative aggregation can be ascribed to the high degree of exposure of the four cysteine residues per subunit. The conformational stability of the dimeric protein was studied by urea- and temperature-induced unfolding techniques. Fluorescence-spectroscopy, SEC-HPLC, urea- and temperature-gradient gel electrophoresis, differential scanning microcalorimetry, and enzyme activity were employed to monitor structural and functional changes. The unfolding data indicate the absence of thermodynamically stable intermediates and that the unfolding/refolding transition is a two-state process involving folded native dimer and unfolded monomer. The stability of the protein was found to be dependent on its concentration, with a delta G degree (H2O) = 26.0 +/- 1.7 kcal/mol. The strong relationship observed between the m-value and the size of the protein indicates that the amount of protein surface area exposed to solvent upon unfolding is the major structural determinant for the dependence of the protein's free energy of unfolding on urea concentration. Thermograms obtained by differential scanning microcalorimetry also fitted a two-state unfolding transition model with values of delta Cp = 7,440 J/mol per K, delta H = 950.4 kJ/mol, and delta S = 1,484 J/mol.

Recognition and Detoxification of the Insecticide DDT by Drosophila melanogaster Glutathione S-Transferase D1

DOE Office of Scientific and Technical Information (OSTI.GOV)

Low, Wai Yee; Feil, Susanne C.; Ng, Hooi Ling

2010-06-14

GSTD1 is one of several insect glutathione S-transferases capable of metabolizing the insecticide DDT. Here we use crystallography and NMR to elucidate the binding of DDT and glutathione to GSTD1. The crystal structure of Drosophila melanogaster GSTD1 has been determined to 1.1 {angstrom} resolution, which reveals that the enzyme adopts the canonical GST fold but with a partially occluded active site caused by the packing of a C-terminal helix against one wall of the binding site for substrates. This helix would need to unwind or be displaced to enable catalysis. When the C-terminal helix is removed from the model ofmore » the crystal structure, DDT can be computationally docked into the active site in an orientation favoring catalysis. Two-dimensional {sup 1}H,{sup 15}N heteronuclear single-quantum coherence NMR experiments of GSTD1 indicate that conformational changes occur upon glutathione and DDT binding and the residues that broaden upon DDT binding support the predicted binding site. We also show that the ancestral GSTD1 is likely to have possessed DDT dehydrochlorinase activity because both GSTD1 from D. melanogaster and its sibling species, Drosophila simulans, have this activity.« less

Glutathione S-transferase P protects against cyclophosphamide-induced cardiotoxicity in mice

DOE Office of Scientific and Technical Information (OSTI.GOV)

Conklin, Daniel J., E-mail: dj.conklin@louisville.edu; Institute of Molecular Cardiology, University of Louisville, Louisville, KY 40292; Haberzettl, Petra

2015-06-01

High-dose chemotherapy regimens using cyclophosphamide (CY) are frequently associated with cardiotoxicity that could lead to myocyte damage and congestive heart failure. However, the mechanisms regulating the cardiotoxic effects of CY remain unclear. Because CY is converted to an unsaturated aldehyde acrolein, a toxic, reactive CY metabolite that induces extensive protein modification and myocardial injury, we examined the role of glutathione S-transferase P (GSTP), an acrolein-metabolizing enzyme, in CY cardiotoxicity in wild-type (WT) and GSTP-null mice. Treatment with CY (100–300 mg/kg) increased plasma levels of creatine kinase-MB isoform (CK·MB) and heart-to-body weight ratio to a significantly greater extent in GSTP-null thanmore » WT mice. In addition to modest yet significant echocardiographic changes following acute CY-treatment, GSTP insufficiency was associated with greater phosphorylation of c-Jun and p38 as well as greater accumulation of albumin and protein–acrolein adducts in the heart. Mass spectrometric analysis revealed likely prominent modification of albumin, kallikrein-1-related peptidase, myoglobin and transgelin-2 by acrolein in the hearts of CY-treated mice. Treatment with acrolein (low dose, 1–5 mg/kg) also led to increased heart-to-body weight ratio and myocardial contractility changes. Acrolein induced similar hypotension in GSTP-null and WT mice. GSTP-null mice also were more susceptible than WT mice to mortality associated with high-dose acrolein (10–20 mg/kg). Collectively, these results suggest that CY cardiotoxicity is regulated, in part, by GSTP, which prevents CY toxicity by detoxifying acrolein. Thus, humans with low cardiac GSTP levels or polymorphic forms of GSTP with low acrolein-metabolizing capacity may be more sensitive to CY toxicity. - Graphical abstract: Cyclophosphamide (CY) treatment results in P450-mediated metabolic formation of phosphoramide mustard and acrolein (3-propenal). Acrolein is either metabolized

Placental biomarkers of PAH exposure and glutathione-S-transferase biotransformation enzymes in an obstetric population from Tijuana, Baja California, Mexico

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dodd-Butera, Teresa, E-mail: tdbutera@csusb.edu

Environmental exposures along the US-Mexico border have the potential to adversely affect the maternal-fetal environment. The purpose of this study was to assess placental biomarkers of environmental exposures in an obstetric population at the California-Baja California border in relation to detoxifying enzymes in the placenta and nutritional status. This study was conducted on consenting, full-term, obstetric patients (n=54), delivering in a hospital in Tijuana, Baja California (BC), Mexico. Placental polyaromatic hydrocarbon (PAH)-DNA adducts were measured in addition to placental glutathione-S-transferase (GST) activity and genotype, maternal serum folate, and maternal and umbilical cord blood lead and cadmium levels. A questionnaire wasmore » administered to the mothers to determine maternal occupation in a maquiladora, other exposures, and obstetric indicators. In univariate analysis, maternal serum folate levels were inversely correlated with total PAH-DNA adducts (rho=−0.375, p=0.007); adduct #1 (rho=−0.388, p=0.005); and adduct #3 (rho =−0.430, p=0.002). Maternal lead levels were significantly positively correlated with cord blood lead levels (rho=0.512, p<0.001). Cadmium levels were generally very low but significantly higher in mothers exposed to environmental tobacco smoke (ETS) (either at work or at home, n=10). In multivariate analysis, only maternal serum folate levels remained as a significant negative predictor of total DNA-PAH adducts levels in placenta. These findings affirm that placental tissue is a valuable and readily available source of human tissue for biomonitoring; and indicate that further study of the role of nutrition in detoxification and mitigation of environmental exposures in pregnant women is warranted. - Highlights: • Maternal-fetal environment susceptible to toxic exposures at US-Mexico border. • Lower serum folate was correlated with higher PAH-DNA adduct levels at birth. • Placental DNA adducts in GST mu (-) cord

Analysis of DNA methylation of maize in response to osmotic and salt stress based on methylation-sensitive amplified polymorphism.

PubMed

Tan, Ming-pu

2010-01-01

Water stress is known to alter cytosine methylation, which generally represses transcription. However, little is known about the role of methylation alteration in maize under osmotic stress. Here, methylation-sensitive amplified polymorphism (MSAP) was used to screen PEG- or NaCl-induced methylation alteration in maize seedlings. The sequences of 25 differentially amplified fragments relevant to stress were successfully obtained. Two stress-specific fragments from leaves, LP166 and LPS911, shown to be homologous to retrotransposon Gag-Pol protein genes, suggested that osmotic stress-induced methylation of retrotransposons. Three MSAP fragments, representing drought-induced or salt-induced methylation in leaves, were homologous to a maize aluminum-induced transporter. Besides these, heat shock protein HSP82, Poly [ADP-ribose] polymerase 2, Lipoxygenase, casein kinase (CK2), and dehydration-responsive element-binding (DREB) factor were also homologs of MSAP sequences from salt-treated roots. One MSAP fragment amplified from salt-treated roots, designated RS39, was homologous to the first intron of maize protein phosphatase 2C (zmPP2C), whereas - LS103, absent from salt-treated leaves, was homologous to maize glutathione S-transferases (zmGST). Expression analysis showed that salt-induced intron methylation of root zmPP2C significantly downregulated its expression, while salt-induced demethylation of leaf zmGST weakly upregulated its expression. The results suggested that salinity-induced methylation downregulated zmPP2C expression, a negative regulator of the stress response, while salinity-induced demethylation upregulated zmGST expression, a positive effecter of the stress response. Altered methylation, in response to stress, might also be involved in stress acclimation. Copyright 2009 Elsevier Masson SAS. All rights reserved.

The Potato Aphid Salivary Effector Me47 Is a Glutathione-S-Transferase Involved in Modifying Plant Responses to Aphid Infestation.

PubMed

Kettles, Graeme J; Kaloshian, Isgouhi

2016-01-01

Polyphagous aphid pests cause considerable economic damage to crop plants, primarily through the depletion of photoassimilates and transfer of viruses. The potato aphid (Macrosiphum euphorbiae) is a notable pest of solanaceous crops, however, the molecular mechanisms that underpin the ability to colonize these hosts are unknown. It has recently been demonstrated that like other aphid species, M. euphorbiae injects a battery of salivary proteins into host plants during feeding. It is speculated that these proteins function in a manner analagous to secreted effectors from phytopathogenic bacteria, fungi and oomycetes. Here, we describe a novel aphid effector (Me47) which was identified from the potato aphid salivary secretome as a putative glutathione-S-transferase (GST). Expression of Me47 in Nicotiana benthamiana enhanced reproductive performance of green peach aphid (Myzus persicae). Similarly, delivery of Me47 into leaves of tomato (Solanum lycopersicum) by Pseudomonas spp. enhanced potato aphid fecundity. In contrast, delivery of Me47 into Arabidopsis thaliana reduced GPA reproductive performance, indicating that Me47 impacts the outcome of plant-aphid interactions differently depending on the host species. Delivery of Me47 by the non-pathogenic Pseudomonas fluorescens revealed that Me47 protein or activity triggers defense gene transcriptional upregulation in tomato but not Arabidopsis. Recombinant Me47 was purified and demonstrated to have GST activity against two specific isothiocyanates (ITCs), compounds implicated in herbivore defense. Whilst GSTs have previously been associated with development of aphid resistance to synthetic insecticides, the findings described here highlight a novel function as both an elicitor and suppressor of plant defense when delivered into host tissues.

A Simple Colorimetric Assay for Specific Detection of Glutathione-S Transferase Activity Associated with DDT Resistance in Mosquitoes

PubMed Central

Rajatileka, Shavanti; Steven, Andrew; Hemingway, Janet; Ranson, Hilary; Paine, Mark; Vontas, John

2010-01-01

Background Insecticide-based methods represent the most effective means of blocking the transmission of vector borne diseases. However, insecticide resistance poses a serious threat and there is a need for tools, such as diagnostic tests for resistance detection, that will improve the sustainability of control interventions. The development of such tools for metabolism-based resistance in mosquito vectors lags behind those for target site resistance mutations. Methodology/Principal Findings We have developed and validated a simple colorimetric assay for the detection of Epsilon class Glutathione transferases (GST)-based DDT resistance in mosquito species, such as Aedes aegypti, the major vector of dengue and yellow fever worldwide. The colorimetric assay is based on the specific alkyl transferase activity of Epsilon GSTs for the haloalkene substrate iodoethane, which produces a dark blue colour highly correlated with AaGSTE2-2-overexpression in individual mosquitoes. The colour can be measured visually and spectrophotometrically. Conclusions/Significance The novel assay is substantially more sensitive compared to the gold standard CDNB assay and allows the discrimination of moderate resistance phenotypes. We anticipate that it will have direct application in routine vector monitoring as a resistance indicator and possibly an important impact on disease vector control. PMID:20824165

Assembly of Multi-tRNA Synthetase Complex via Heterotetrameric Glutathione Transferase-homology Domains.

PubMed

Cho, Ha Yeon; Maeng, Seo Jin; Cho, Hyo Je; Choi, Yoon Seo; Chung, Jeong Min; Lee, Sangmin; Kim, Hoi Kyoung; Kim, Jong Hyun; Eom, Chi-Yong; Kim, Yeon-Gil; Guo, Min; Jung, Hyun Suk; Kang, Beom Sik; Kim, Sunghoon

2015-12-04

Many multicomponent protein complexes mediating diverse cellular processes are assembled through scaffolds with specialized protein interaction modules. The multi-tRNA synthetase complex (MSC), consisting of nine different aminoacyl-tRNA synthetases and three non-enzymatic factors (AIMP1-3), serves as a hub for many signaling pathways in addition to its role in protein synthesis. However, the assembly process and structural arrangement of the MSC components are not well understood. Here we show the heterotetrameric complex structure of the glutathione transferase (GST) domains shared among the four MSC components, methionyl-tRNA synthetase (MRS), glutaminyl-prolyl-tRNA synthetase (EPRS), AIMP2 and AIMP3. The MRS-AIMP3 and EPRS-AIMP2 using interface 1 are bridged via interface 2 of AIMP3 and EPRS to generate a unique linear complex of MRS-AIMP3:EPRS-AIMP2 at the molar ratio of (1:1):(1:1). Interestingly, the affinity at interface 2 of AIMP3:EPRS can be varied depending on the occupancy of interface 1, suggesting the dynamic nature of the linear GST tetramer. The four components are optimally arranged for maximal accommodation of additional domains and proteins. These characteristics suggest the GST tetramer as a unique and dynamic structural platform from which the MSC components are assembled. Considering prevalence of the GST-like domains, this tetramer can also provide a tool for the communication of the MSC with other GST-containing cellular factors. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

An analysis of Methylenetetrahydrofolate reductase and Glutathione S-transferase omega-1 genes as modifiers of the cerebral response to ischemia

PubMed Central

Peddareddygari, Leema Reddy; Dutra, Ana Virginia; Levenstien, Mark A; Sen, Souvik; Grewal, Raji P

2009-01-01

Background Cerebral ischemia involves a series of reactions which ultimately influence the final volume of a brain infarction. We hypothesize that polymorphisms in genes encoding proteins involved in these reactions could act as modifiers of the cerebral response to ischemia and impact the resultant stroke volume. The final volume of a cerebral infarct is important as it correlates with the morbidity and mortality associated with non-lacunar ischemic strokes. Methods The proteins encoded by the methylenetetrahydrofolate reductase (MTHFR) and glutathione S-transferase omega-1 (GSTO-1) genes are, through oxidative mechanisms, key participants in the cerebral response to ischemia. On the basis of these biological activities, they were selected as candidate genes for further investigation. We analyzed the C677T polymorphism in the MTHFR gene and the C419A polymorphism in the GSTO-1 gene in 128 patients with non-lacunar ischemic strokes. Results We found no significant association of either the MTHFR (p = 0.72) or GSTO-1 (p = 0.58) polymorphisms with cerebral infarct volume. Conclusion Our study shows no major gene effect of either the MTHFR or GSTO-1 genes as a modifier of ischemic stroke volume. However, given the relatively small sample size, a minor gene effect is not excluded by this investigation. PMID:19624857

The Potato Aphid Salivary Effector Me47 Is a Glutathione-S-Transferase Involved in Modifying Plant Responses to Aphid Infestation

PubMed Central

Kettles, Graeme J.; Kaloshian, Isgouhi

2016-01-01

Polyphagous aphid pests cause considerable economic damage to crop plants, primarily through the depletion of photoassimilates and transfer of viruses. The potato aphid (Macrosiphum euphorbiae) is a notable pest of solanaceous crops, however, the molecular mechanisms that underpin the ability to colonize these hosts are unknown. It has recently been demonstrated that like other aphid species, M. euphorbiae injects a battery of salivary proteins into host plants during feeding. It is speculated that these proteins function in a manner analagous to secreted effectors from phytopathogenic bacteria, fungi and oomycetes. Here, we describe a novel aphid effector (Me47) which was identified from the potato aphid salivary secretome as a putative glutathione-S-transferase (GST). Expression of Me47 in Nicotiana benthamiana enhanced reproductive performance of green peach aphid (Myzus persicae). Similarly, delivery of Me47 into leaves of tomato (Solanum lycopersicum) by Pseudomonas spp. enhanced potato aphid fecundity. In contrast, delivery of Me47 into Arabidopsis thaliana reduced GPA reproductive performance, indicating that Me47 impacts the outcome of plant–aphid interactions differently depending on the host species. Delivery of Me47 by the non-pathogenic Pseudomonas fluorescens revealed that Me47 protein or activity triggers defense gene transcriptional upregulation in tomato but not Arabidopsis. Recombinant Me47 was purified and demonstrated to have GST activity against two specific isothiocyanates (ITCs), compounds implicated in herbivore defense. Whilst GSTs have previously been associated with development of aphid resistance to synthetic insecticides, the findings described here highlight a novel function as both an elicitor and suppressor of plant defense when delivered into host tissues. PMID:27536306

Modulation of ethoxyresorufin O-deethylase and glutathione S-transferase activities in Nile tilapia (Oreochromis niloticus) by polycyclic aromatic hydrocarbons containing two to four rings: implications in biomonitoring aquatic pollution.

PubMed

Pathiratne, Asoka; Hemachandra, Chamini K

2010-08-01

Despite ubiquity of polycyclic aromatic hydrocarbons (PAHs) in the tropical environments, little information is available concerning responses of tropical fish to PAHs and associated toxicity. In the present study, effects of five PAHs containing two to four aromatic rings on hepatic CYP1A dependent ethoxyresorufin O-deethylase (EROD), glutathione S-transferase (GST) and serum sorbitol dehydrogenase (SDH) activities in Nile tilapia, a potential fish species for biomonitoring pollution in tropical waters, were evaluated. Results showed that EROD activities were induced by the PAHs containing four aromatic rings (pyrene and chrysene) in a dose dependent manner. However PAHs with two to three aromatic rings (naphthalene, phenanthrene and fluoranthene) caused no effect or inhibition of EROD activities depending on the dose and the duration. Fluoranthene was the most potent inhibitor. SDH results demonstrated that high doses of fluoranthene induced hepatic damage. GST activity was induced by the lowest dose of phenanthrene, fluoranthene and chrysene but high doses had no effect. The results indicate that induction of EROD enzyme in Nile tilapia is a useful biomarker of exposure to PAHs such as pyrene and chrysene. However EROD inhibiting PAHs such as fluoranthene in the natural environment may modulate the EROD inducing potential of other PAHs thereby influencing PAH exposure assessments.

Cyclopentenone prostaglandins as potential inducers of phase II detoxification enzymes. 15-deoxy-delta(12,14)-prostaglandin j2-induced expression of glutathione S-transferases.

PubMed

Kawamoto, Y; Nakamura, Y; Naito, Y; Torii, Y; Kumagai, T; Osawa, T; Ohigashi, H; Satoh, K; Imagawa, M; Uchida, K

2000-04-14

Exposure of cells to a wide variety of chemoprotective compounds confers resistance to a broad set of carcinogens. For a subset of the chemoprotective compounds, protection is generated by an increase in the abundance of protective enzymes, such as glutathione S-transferases (GSTs). In the present study, we developed a cell culture system that potently responds to phenolic antioxidants and found that antitumor prostaglandins (PGs) are potential inducers of GSTs. We screened primary hepatocytes and multiple cell lines for inducing GST activity upon incubation with the phenolic antioxidant (tert-butylhydroquinone) and found that rat liver epithelial RL34 cells most potently responded. Based on an extensive screening of diverse chemical agents on the induction of GST activity in RL34 cells, the J2 series of PGs, 15-deoxy-Delta(12,14)-prostaglandin J2 (15-deoxy-Delta(12,14)-PGJ2) in particular, were found to be potential inducers of GST. Enhanced gene expression of Class pi GST isozyme (GSTP1) by 15-deoxy-Delta(12,14)-PGJ2 was evident as a drastic elevation of the mRNA level. Hence, we examined the molecular mechanism underlying the 15-deoxy-Delta(12, 14)-PGJ2-induced GSTP1 gene expression. From functional analysis of various deletion mutant genes, we found that the 15-deoxy-Delta(12, 14)-PGJ2 reponse element was localized in a region containing a GSTP1 enhancer I (GPEI) that consists of two imperfect phorbol 12-O-tetradecanoylphorbol-13-acetate response elements. When the GPEI was combined with the minimum GSTP1 promoter, the element indeed showed an enhancer activity in response to 15-deoxy-Delta(12, 14)-PGJ2. Point mutations of either of the two imperfect 12-O-tetradecanoylphorbol-13-acetate response elements in GPEI completely abolished the enhancer activity. Gel mobility shift assays demonstrated that 15-deoxy-Delta(12,14)-PGJ2 specifically stimulated the binding of nuclear proteins including the transcription factor c-Jun, but not Nrf2, to GPEI. These results

Down-regulation of Glutathione S-transferase Pi in Asthma Contributes to Enhanced Oxidative Stress

PubMed Central

Schroer, Kathy T.; Gibson, Aaron M.; Sivaprasad, Umasundari; Bass, Stacey A.; Ericksen, Mark B.; Wills-Karp, Marsha; LeCras, Tim; Fitzpatrick, Anne M.; Brown, Lou Ann S.; Stringer, Keith F.; Khurana Hershey, Gurjit K.

2011-01-01

Background Glutathione S-transferase Pi (GSTPi) is the predominant redox regulator in the lung. While evidence implicates an important role for GSTPi in asthma, the mechanism for this has remained elusive. Objectives To determine how GSTPi is regulated in asthma and to elucidate its role in maintaining redox homeostasis. Methods We elucidated the regulation of GSTPi in children with asthma and utilized murine models of asthma to determine the role of GSTPi in redox homeostasis. Measurements and Main Results Our findings demonstrate that GSTPi transcript levels are markedly down-regulated in allergen and IL-13 treated mouse models of asthma via STAT6 dependent and independent pathways. Nuclear factor-erythroid 2 related factor 2 (Nrf2) was also down-regulated in these models. The decrease in GSTPi expression was associated with decreased total GST activity in the lungs of mice. Examination of cystine intermediates uncovered a functional role for GSTPi in regulating Cys oxidation, whereby GSTPi-deficient mice exhibited increased oxidative stress (increase in % cystine) compared with wild-type mice following allergen challenge. GSTPi expression was similarly down-regulated in children with asthma. Conclusions These data collectively suggest that down-regulation of GSTPi following allergen challenge may contribute to the asthma phenotype due to disruption of redox homeostasis and increased oxidative stress. Furthermore, GSTPi may be an important therapeutic target for asthma, and evaluation of GSTPi expression may prove beneficial in identifying individuals who would benefit from therapy targeting this pathway. PMID:21570714

Identification of glutathione S-transferases in Bemisia tabaci (Hemiptera: Aleyrodidae) and evidence that GSTd7 helps explain the difference in insecticide susceptibility between B. tabaci Middle East-Minor Asia 1 and Mediterranean.

PubMed

He, C; Xie, W; Yang, X; Wang, S-L; Wu, Q-J; Zhang, Y-J

2018-02-01

The Bemisia tabaci (Gennadius) (Hemiptera:Aleyrodidae) species complex includes invasive and destructive pests of field crops, and the sibling species MEAM1 and MED are its two most damaging members. Previous research indicated that the replacement of Middle East-Minor Asia 1 (MEAM1) by Mediterranean (MED) as the dominant B. tabaci species in China can be mainly attributed to MED's greater tolerance to insecticides. Glutathione S-transferases (GSTs) play important roles in the detoxification of hydrophobic toxic compounds. To increase our understanding of differences in insecticide resistance between B. tabaci MEAM1 and MED, we searched the genomic and transcriptomic databases and identified 23 putative GSTs in both B. tabaci MEAM1 and MED. Through measuring mRNA levels of 18 of the GSTs after B. tabaci MEAM1 and MED adults were exposed to the insecticide imidacloprid, we found that the expression levels were increased more in B. tabaci MED than in MEAM1 (in particular, the expression level of GST-d7 was increased by 4.39-fold relative to the control). Knockdown of GST-d7 in B. tabaci MED but not in B. tabaci MEAM1 resulted in a substantial increase in the mortality of imidacloprid-treated adults. These results indicate that differences in GST-d7 may help explain why insecticide tolerance is greater in B. tabaci MED than in B. tabaci MEAM1. © 2017 The Royal Entomological Society.

Molecular evolution of Theta-class glutathione transferase for enhanced activity with the anticancer drug 1,3-bis-(2-chloroethyl)-1-nitrosourea and other alkylating agents.

PubMed

Larsson, Anna-Karin; Shokeer, Abeer; Mannervik, Bengt

2010-05-01

Glutathione transferase (GST) displaying enhanced activity with the cytostatic drug 1,3-bis-(2-chloroethyl)-1-nitrosourea (BCNU) and structurally related alkylating agents was obtained by molecular evolution. Mutant libraries created by recursive recombination of cDNA coding for human and rodent Theta-class GSTs were heterologously expressed in Escherichia coli and screened with the surrogate substrate 4-nitrophenethyl bromide (NPB) for enhanced alkyltransferase activity. A mutant with a 70-fold increased catalytic efficiency with NPB, compared to human GST T1-1, was isolated. The efficiency in degrading BCNU had improved 170-fold, significantly more than with the model substrate NPB. The enhanced catalytic activity of the mutant GST was also 2-fold higher with BCNU than wild-type mouse GST T1-1, which is 80-fold more efficient than wild-type human GST T1-1. We propose that GSTs catalyzing inactivation of anticancer drugs may find clinical use in protecting sensitive normal tissues to toxic side-effects in treated patients, and as selectable markers in gene therapy. Copyright 2010 Elsevier Inc. All rights reserved.

RNA interference of two glutathione S-transferase genes, Diaphorina citri DcGSTe2 and DcGSTd1, increases the susceptibility of Asian citrus psyllid (Hemiptera: Liviidae) to the pesticides fenpropathrin and thiamethoxam.

PubMed

Yu, Xiudao; Killiny, Nabil

2018-03-01

The Asian citrus psyllid, Diaphorina citri Kuwayama, is an important agricultural pest of citrus globally. Foliar application of chemical insecticides is the most widely used option for reducing D. citri populations. Knockdown of glutathione S-transferase (GST) in several insect species leads to increased susceptibility to insecticides; however, information about the detoxifying role of GST genes in D. citri is unavailable. Via a sequence homology search, we isolated and characterized three DcGST genes (DcGSTd1, DcGSTe1 and DcGSTe2) from D. citri. Phylogenetic analysis grouped DcGSTd1 into the delta class of GST genes, whereas DcGSTe1 and DcGSTe2 were clustered in the epsilon clade. Gene expression analysis revealed that chlorpyrifos treatment increased the mRNA levels of DcGSTe1 and fenpropathrin enhanced the expression level of DcGSTd1, while DcGSTe2 was significantly up-regulated after exposure to thiamethoxam at a dose of 30% lethal concentration (LC30). RNA interference (RNAi) of DcGSTe2 and DcGSTd1 followed by an insecticide bioassay increased the mortalities of thiamethoxam-treated psyllids by 23.0% and fenpropathrin-treated psyllids by 15.0%. In contrast, knockdown of DcGSTe1 did not significantly increase the susceptibility of D. citri to any of these three insecticides. Further, feeding with double-stranded RNA (dsDcGSTe2-d1) interfusion co-silenced DcGSTe2 and DcGSTd1 expression in D. citri, and led to an increase of susceptibility to both fenpropathrin and thiamethoxam. The findings suggest that DcGSTe2 and DcGSTd1 play unique roles in detoxification of the pesticides thiamethoxam and fenpropathrin. In addition, co-silencing by creating a well-designed dsRNA interfusion against multiple genes was a good RNAi strategy in D. citri. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Glutathione S-transferase M1 (GSTM1) polymorphisms and lung cancer: a literature-based systematic HuGE review and meta-analysis.

PubMed

Carlsten, C; Sagoo, G S; Frodsham, A J; Burke, W; Higgins, J P T

2008-04-01

Multiple genes have been studied for potential associations with lung cancer. The gene most frequently associated with increased risk has been glutathione S-transferase M1 (GSTM1). The glutathione S-transferase enzyme family is known to catalyze detoxification of electrophilic compounds, including carcinogens, therapeutic drugs, environmental toxins, and products of oxidative stress. In this review, the authors summarize the available evidence associating lung cancer with the GSTM1 gene. They describe results from an updated meta-analysis of 98 published genetic association studies investigating the relation between the GSTM1 null variant and lung cancer risk including 19,638 lung cancer cases and 25,266 controls (counting cases and controls in each study only once). All studies considered, the GSTM1 null variant was associated with an increased risk of lung cancer (odds ratio (OR) = 1.22, 95% confidence interval (CI): 1.14, 1.30), but no increase in risk was seen (OR = 1.01, 95% CI: 0.91, 1.12) when only the five largest studies (>500 cases each) were considered. Furthermore, while GSTM1 null status conferred a significantly increased risk of lung cancer to East Asians (OR = 1.38, 95% CI: 1.24, 1.55), such a genotype did not confer increased risk to Caucasians. More data regarding the predictive value of GSTM1 genetic testing are needed before population-based testing may be reasonably considered.

Overlapping protective roles for glutathione transferase gene family members in chemical and oxidative stress response in Agrobacterium tumefaciens.

PubMed

Skopelitou, Katholiki; Muleta, Abdi W; Pavli, Ourania; Skaracis, Georgios N; Flemetakis, Emmanouil; Papageorgiou, Anastassios C; Labrou, Nikolaos E

2012-03-01

In the present work, we describe the characterisation of the glutathione transferase (GST) gene family from Agrobacterium tumefaciens C58. A genome survey revealed the presence of eight GST-like proteins in A. tumefaciens (AtuGSTs). Comparison by multiple sequence alignment generated a dendrogram revealing the phylogenetic relationships of AtuGSTs-like proteins. The beta and theta classes identified in other bacterial species are represented by five members in A. tumefaciens C58. In addition, there are three "orphan" sequences that do not fit into any previously recognised GST classes. The eight GST-like genes were cloned, expressed in Escherichia coli and their substrate specificity was determined towards 17 different substrates. The results showed that AtuGSTs catalyse a broad range of reactions, with different members of the family exhibiting quite varied substrate specificity. The 3D structures of AtuGSTs were predicted using molecular modelling. The use of comparative sequence and structural analysis of the AtuGST isoenzymes allowed us to identify local sequence and structural characteristics between different GST isoenzymes and classes. Gene expression profiling was conducted under normal culture conditions as well as under abiotic stress conditions (addition of xenobiotics, osmotic stress and cold and heat shock) to induce and monitor early stress-response mechanisms. The results reveal the constitutive expression of GSTs in A. tumefaciens and a modulation of GST activity after treatments, indicating that AtuGSTs presumably participate in a wide range of functions, many of which are important in counteracting stress conditions. These functions may be relevant to maintaining cellular homeostasis as well as in the direct detoxification of toxic compounds.

Inhibition of JNK by pi class of glutathione S-transferase through PKA/CREB pathway is associated with carnosic acid protection against 6-hydroxydopamine-induced apoptosis.

PubMed

Lin, Chia-Yuan; Fu, Ru-Huei; Chou, Ruey-Hwang; Chen, Jing-Hsien; Wu, Chi-Rei; Chang, Shu-Wei; Tsai, Chia-Wen

2017-05-01

Pi class of glutathione S-transferase (GST) is known to suppress c-Jun N-terminal kinase (JNK)-related apoptosis through protein-protein interactions. Moreover, signaling by PKA/cAMP response element binding protein (CREB) is necessary for GSTP up-regulation. This study explored whether carnosic acid (CA) from rosemary prevents 6-hydroxydopamine (6-OHDA)-induced neurotoxicity by inhibition of JNK through GSTP via PKA/CREB signaling. Results indicated that the GSTP protein was increased in SH-SY5Y cells treated with CA for 18 and 24 h. However, CA had no significant effect on alpha or mu class of GST. Treatment of CA increased the induction of p-PKAα, nuclear p-CREB, and CRE-DNA binding activity. These effects of CA were attenuated in cells pretreated with the PKA inhibitor H89. CA pretreatment suppressed 6-OHDA-induced apoptosis by inhibition of JNK phosphorylation, poly(ADP)-ribose polymerase cleavage, and nuclear condensation. Pretreatment with H89 and GSTP siRNA attenuated the ability of CA to reverse 6-OHDA-induced apoptosis. By use of immunoprecipitation with JNK antibody to examine the interaction of GSTP-JNK with CA, we showed that CA pretreatment increased the immunoprecipitation of GSTP after 6-OHDA treatment, which suggests that CA promoted the interaction between GSTP and JNK. CA prevents 6-OHDA-induced apoptosis via inhibition of JNK by GSTP through the PKA/CREB pathway. Copyright © 2017 Elsevier Ltd. All rights reserved.

CYP1A1 and GSTM1 genetic polymorphisms in lung cancer populations exposed to arsenic in drinking water.

PubMed

Adonis, M; Martínez, V; Marín, P; Gil, L

2005-05-01

Region II of Chile is the most important copper mining area in the world and it shows the highest lung cancer mortality rate in the country (35/100,000). The population in Antofagasta, the main city of Region II, was exposed from 1958 to 1970 to 860 microg m(-3) arsenic (As) in drinking water and has currently been declining to 40 microg m(-3). Glutathione serves as a reducing agent and glutathione S-transferase (GST) may have an important role in As methylation capacity and body retention. In the current study, the null genotype of GSTM1 and the MspI polymorphism of CYP450 1A1 were investigated in lung cancer patients and in healthy volunteers of Region II. In males, the 2A genotype of MspI represented a highly significant estimated relative lung cancer risk (OR=2.60). Relative lung cancer risk for the combined 2A/null GSTM1 genotypes was 2.51, which increased with the smoking habit (OR=2.98). In Region II, the cancer mortality rate for As-associated cancers at least partly might be related to differences in As biotransformation. Genetic biomarkers such as 2A and GSTM1 polymorphisms in addition to DR70 as screening biomarkers might provide relevant information to identify individuals with a high risk for lung cancer as prevention and protection actions to protect public health.

Reaction of rat liver glutathione S-transferases and bacterial dichloromethane dehalogenase with dihalomethanes.

PubMed

Blocki, F A; Logan, M S; Baoli, C; Wackett, L P

1994-03-25

Dichloromethane dehalogenase from Methylophilus sp. DM11 is a glutathione S-transferase homolog that is specifically active with dihalomethane substrates. This bacterial enzyme and rat liver glutathione S-transferases were purified to investigate their relative reactivity with CH2Cl2 and related substrates. Rat liver alpha class glutathione transferases were inactive and mu class enzymes showed low activity (7-23 nmol/min/mg of protein) with CH2Cl2. theta class glutathione transferase 5-5 from rat liver and Methylophilus sp. dichloromethane dehalogenase showed specific activities of > or = 1 mumol/min/mg of protein. Apparent Kcat/Km were determined to be 3.3 x 10(4) and 6.0 x 10(4) L M-1 S-1 for the two enzymes, respectively. Dideutero-dichloromethane was processed to dideutereo-formaldehyde, consistent with a nucleophilic halide displacement mechanism. The possibility of a GSCH2X reaction intermediate (GS, glutathione; X, halide) was probed using CH2ClF to generate a more stable halomethylglutathione species (GSCH2F). The reaction of CH2ClF with dichloromethane dehalogenase produced a kinetically identifiable intermediate that decomposed to formaldehyde at a similar rate to synthetic HOCH2CH2SCH2F. 19F-NMR revealed the transient formation of an intermediate identified as GSCH2F by its chemical shift, its triplet resonance, and H-F coupling constant consistent with a fluoromethylthioether. Its decomposition was matched by a stoichiometric formation of fluoride. These studies indicated that the bacterial dichloromethane dehalogenase directs a nucleophilic attack of glutathione on CH2Cl2 to produce a halomethylthioether intermediate. This focuses attention on the mechanism used by theta class glutathione transferases to generate a halomethylthioeter from relatively unreactive dihalomethanes.

Blood glutathione S-transferase-π as a time indicator of stroke onset.

PubMed

Turck, Natacha; Robin, Xavier; Walter, Nadia; Fouda, Catherine; Hainard, Alexandre; Sztajzel, Roman; Wagner, Ghislaine; Hochstrasser, Denis F; Montaner, Joan; Burkhard, Pierre R; Sanchez, Jean-Charles

2012-01-01

Ability to accurately determine time of stroke onset remains challenging. We hypothesized that an early biomarker characterized by a rapid increase in blood after stroke onset may help defining better the time window during which an acute stroke patient may be candidate for intravenous thrombolysis or other intravascular procedures. The blood level of 29 proteins was measured by immunoassays on a prospective cohort of stroke patients (N = 103) and controls (N = 132). Mann-Whitney U tests, ROC curves and diagnostic odds ratios were applied to evaluate their clinical performances. Among the 29 molecules tested, GST-π concentration was the most significantly elevated marker in the blood of stroke patients (p<0.001). More importantly, GST-π displayed the best area under the curve (AUC, 0.79) and the best diagnostic odds ratios (10.0) for discriminating early (N = 22, <3 h of stroke onset) vs. late stroke patients (N = 81, >3 h after onset). According to goal-oriented distinct cut-offs (sensitivity(Se)-oriented: 17.7 or specificity(Sp)-oriented: 65.2 ug/L), the GST-π test obtained 91%Se/50%Sp and 50%Se/91%Sp, respectively. Moreover, GST-π showed also the highest AUC (0.83) and performances for detecting patients treated with tPA (N = 12) compared to ineligible patients (N = 103). This study demonstrates that GST-π can accurately predict the time of stroke onset in over 50% of early stroke patients. The GST-π test could therefore complement current guidelines for tPA administration and potentially increase the number of patients accessing thrombolysis.

Integrated assessment of biomarker responses and microbiological analysis of oysters from São Luís Island, Brazil.

PubMed

Ribeiro, E B; Bastos, L S; Galeno, L S; Mendes, R S; Garino, F; Carvalho-Neta, R N F; Costa, F N

2016-12-15

This study was conducted to evaluate the use of biochemical biomarkers and microbiological analysis to identify levels of oyster contamination at different ports in São Luís Island (Maranhão), Brazil. Oysters were analyzed for total coliforms, thermotolerant coliforms, Escherichia coli and Aeromonas spp. In addition, tissue was removed from the digestive gland to determine the glutathione-S-transferase (GST) and catalase (CAT) activity. The highest percentage of microbiological contamination of oyster samples occurred during the rainy season. The activity of GST and catalase in oysters was also higher in the rainy season, coinciding with the greatest abundance of total and thermotolerant coliforms. Among the prospective biomarkers, GST showed the best results for identification of areas with higher levels of contamination. Copyright © 2016 Elsevier Ltd. All rights reserved.

Multiple Pesticides Detoxification Function of Maize (Zea mays) GST34.

PubMed

Li, Dongzhi; Xu, Li; Pang, Sen; Liu, Zhiqian; Zhao, Weisong; Wang, Chengju

2017-03-08

ZmGST34 is a maize Tau class GST gene and was found to be differently expressed between two maize cultivars differing in tolerance to herbicide metolachlor. To explore the possible role of ZmGST34 in maize development, the expression pattern and substrate specificity of ZmGST34 were characterized by quantitative RT-PCR and heterologous expression system, respectively. The results indicated that the expression level of ZmGST34 was increased ∼2-5-fold per day during the second-leaf stage of maize seedling. Chloroacetanilide herbicides or phytohormone treatments had no influence on the expression level of ZmGST34, suggesting that ZmGST34 is a constitutively expressed gene in maize seedling. Heterologous expression in Escherichia coli and in Arabidopsis thaliana proved that ZmGST34 can metabolize most chloroacetanilide herbicides and increase tolerance to these herbicides in transgenic Arabidopsis thaliana. The constitutive expression pattern and broad substrate activity of ZmGST34 suggested that this gene may play an important role in maize development in addition to the detoxification of pesticides.

Glutathione S-Transferase Gene Polymorphisms: Modulator of Genetic Damage in Gasoline Pump Workers.

PubMed

Priya, Kanu; Yadav, Anita; Kumar, Neeraj; Gulati, Sachin; Aggarwal, Neeraj; Gupta, Ranjan

2015-01-01

This study investigated genetic damage in gasoline pump workers using the cytokinesis blocked micronucleus (CBMN) assay. Blood and urine samples were collected from 50 gasoline pump workers and 50 control participants matched with respect to age and other confounding factors except for exposure to benzene through gasoline vapors. To determine the benzene exposure, phenol was analyzed in urinary samples of exposed and control participants. Urinary mean phenol level was found to be significantly high (P < 0.05) in exposed workers. The CBMN frequency was found to be significantly higher in gasoline pump workers (6.70 ± 1.78) when compared to control individuals (2.20 ± 0.63; P < 0.05). We also investigated influence of polymorphisms of GSTM1, GSTT1, and GSTP1 genes on CBMN frequency. The individuals having GSTM1 and GSTT1 null genotypes had significantly higher frequency of CBMN (P < 0.05). Our study indicates that chronic and long-term exposure of gasoline vapors can increase genotoxic risk in gasoline pump workers. © The Author(s) 2015.

Structure of a Highly Active Cephalopod S-crystallin Mutant: New Molecular Evidence for Evolution from an Active Enzyme into Lens-Refractive Protein

PubMed Central

Tan, Wei-Hung; Cheng, Shu-Chun; Liu, Yu-Tung; Wu, Cheng-Guo; Lin, Min-Han; Chen, Chiao-Che; Lin, Chao-Hsiung; Chou, Chi-Yuan

2016-01-01

Crystallins are found widely in animal lenses and have important functions due to their refractive properties. In the coleoid cephalopods, a lens with a graded refractive index provides good vision and is required for survival. Cephalopod S-crystallin is thought to have evolved from glutathione S-transferase (GST) with various homologs differentially expressed in the lens. However, there is no direct structural information that helps to delineate the mechanisms by which S-crystallin could have evolved. Here we report the structural and biochemical characterization of novel S-crystallin-glutathione complex. The 2.35-Å crystal structure of a S-crystallin mutant from Octopus vulgaris reveals an active-site architecture that is different from that of GST. S-crystallin has a preference for glutathione binding, although almost lost its GST enzymatic activity. We’ve also identified four historical mutations that are able to produce a “GST-like” S-crystallin that has regained activity. This protein recapitulates the evolution of S-crystallin from GST. Protein stability studies suggest that S-crystallin is stabilized by glutathione binding to prevent its aggregation; this contrasts with GST-σ, which do not possess this protection. We suggest that a tradeoff between enzyme activity and the stability of the lens protein might have been one of the major driving force behind lens evolution. PMID:27499004

Antioxidant role of glutathione S-transferases: 4-Hydroxynonenal, a key molecule in stress-mediated signaling

DOE Office of Scientific and Technical Information (OSTI.GOV)

Singhal, Sharad S., E-mail: ssinghal@coh.org; Singh, Sharda P.; Singhal, Preeti

2015-12-15

4-Hydroxy-2-trans-nonenal (4HNE), one of the major end products of lipid peroxidation (LPO), has been shown to induce apoptosis in a variety of cell lines. It appears to modulate signaling processes in more than one way because it has been suggested to have a role in signaling for differentiation and proliferation. It has been known that glutathione S-transferases (GSTs) can reduce lipid hydroperoxides through their Se-independent glutathione-peroxidase activity and that these enzymes can also detoxify LPO end-products such as 4HNE. Available evidence from earlier studies together with results of recent studies in our laboratories strongly suggests that LPO products, particularly hydroperoxidesmore » and 4HNE, are involved in the mechanisms of stress-mediated signaling and that it can be modulated by the alpha-class GSTs through the regulation of the intracellular concentrations of 4HNE. We demonstrate that 4HNE induced apoptosis in various cell lines is accompanied with c-Jun-N-terminal kinase (JNK) and caspase-3 activation. Cells exposed to mild, transient heat or oxidative stress acquire the capacity to exclude intracellular 4HNE at a faster rate by inducing GSTA4-4 which conjugates 4HNE to glutathione (GSH), and RLIP76 which mediates the ATP-dependent transport of the GSH-conjugate of 4HNE (GS-HNE). The balance between formation and exclusion promotes different cellular processes — higher concentrations of 4HNE promote apoptosis; whereas, lower concentrations promote proliferation. In this article, we provide a brief summary of the cellular effects of 4HNE, followed by a review of its GST-catalyzed detoxification, with an emphasis on the structural attributes that play an important role in the interactions with alpha-class GSTA4-4. Taken together, 4HNE is a key signaling molecule and that GSTs being determinants of its intracellular concentrations, can regulate stress-mediated signaling, are reviewed in this article. - Highlights: • GSTs are the major

Reversal of hypermethylation and reactivation of glutathione S-transferase pi 1 gene by curcumin in breast cancer cell line.

PubMed

Kumar, Umesh; Sharma, Ujjawal; Rathi, Garima

2017-02-01

One of the mechanisms for epigenetic silencing of tumor suppressor genes is hypermethylation of cytosine residue at CpG islands at their promoter region that contributes to malignant progression of tumor. Therefore, activation of tumor suppressor genes that have been silenced by promoter methylation is considered to be very attractive molecular target for cancer therapy. Epigenetic silencing of glutathione S-transferase pi 1, a tumor suppressor gene, is involved in various types of cancers including breast cancer. Epigenetic silencing of tumor suppressor genes can be reversed by several molecules including natural compounds such as polyphenols that can act as a hypomethylating agent. Curcumin has been found to specifically target various tumor suppressor genes and alter their expression. To check the effect of curcumin on the methylation pattern of glutathione S-transferase pi 1 gene in MCF-7 breast cancer cell line in dose-dependent manner. To check the reversal of methylation pattern of hypermethylated glutathione S-transferase pi 1, MCF-7 breast cancer cell line was treated with different concentrations of curcumin for different time periods. DNA and proteins of treated and untreated cell lines were isolated, and methylation status of the promoter region of glutathione S-transferase pi 1 was analyzed using methylation-specific polymerase chain reaction assay, and expression of this gene was analyzed by immunoblotting using specific antibodies against glutathione S-transferase pi 1. A very low and a nontoxic concentration (10 µM) of curcumin treatment was able to reverse the hypermethylation and led to reactivation of glutathione S-transferase pi 1 protein expression in MCF-7 cells after 72 h of treatment, although the IC 50 value of curcumin was found to be at 20 µM. However, curcumin less than 3 µM of curcumin could not alter the promoter methylation pattern of glutathione S-transferase pi 1. Treatment of breast cancer MCF-7 cells with curcumin

Glutathione S-transferases and UDP-glycosyltransferases Are Involved in Response to Aluminum Stress in Flax

PubMed Central

Dmitriev, Alexey A.; Krasnov, George S.; Rozhmina, Tatiana A.; Kishlyan, Natalya V.; Zyablitsin, Alexander V.; Sadritdinova, Asiya F.; Snezhkina, Anastasiya V.; Fedorova, Maria S.; Yurkevich, Olga Y.; Muravenko, Olga V.; Bolsheva, Nadezhda L.; Kudryavtseva, Anna V.; Melnikova, Nataliya V.

2016-01-01

About 30% of the world's ice-free land area is occupied by acid soils. In soils with pH below 5, aluminum (Al) releases to the soil solution, and becomes highly toxic for plants. Therefore, breeding of varieties that are resistant to Al is needed. Flax (Linum usitatissimum L.) is grown worldwide for fiber and seed production. Al toxicity in acid soils is a serious problem for flax cultivation. However, very little is known about mechanisms of flax resistance to Al and the genetics of this resistance. In the present work, we sequenced 16 transcriptomes of flax cultivars resistant (Hermes and TMP1919) and sensitive (Lira and Orshanskiy) to Al, which were exposed to control conditions and aluminum treatment for 4, 12, and 24 h. In total, 44.9–63.3 million paired-end 100-nucleotide reads were generated for each sequencing library. Based on the obtained high-throughput sequencing data, genes with differential expression under aluminum exposure were revealed in flax. The majority of the top 50 up-regulated genes were involved in transmembrane transport and transporter activity in both the Al-resistant and Al-sensitive cultivars. However, genes encoding proteins with glutathione transferase and UDP-glycosyltransferase activity were in the top 50 up-regulated genes only in the flax cultivars resistant to aluminum. For qPCR analysis in extended sampling, two UDP-glycosyltransferases (UGTs), and three glutathione S-transferases (GSTs) were selected. The general trend of alterations in the expression of the examined genes was the up-regulation under Al stress, especially after 4 h of Al exposure. Moreover, in the flax cultivars resistant to aluminum, the increase in expression was more pronounced than that in the sensitive cultivars. We speculate that the defense against the Al toxicity via GST antioxidant activity is the probable mechanism of the response of flax plants to aluminum stress. We also suggest that UGTs could be involved in cell wall modification and protection

Pummelo Protects Doxorubicin-Induced Cardiac Cell Death by Reducing Oxidative Stress, Modifying Glutathione Transferase Expression, and Preventing Cellular Senescence

PubMed Central

Chularojmontri, L.; Gerdprasert, O.; Wattanapitayakul, S. K.

2013-01-01

Citrus flavonoids have been shown to reduce cardiovascular disease (CVD) risks prominently due to their antioxidant effects. Here we investigated the protective effect of pummelo (Citrus maxima, CM) fruit juice in rat cardiac H9c2 cells against doxorubicin (DOX-) induced cytotoxicity. Four antioxidant compositions (ascorbic acid, hesperidin, naringin, and gallic acid) were determined by HPLC. CM significantly increased cardiac cell survival from DOX toxicity as evaluated by MTT assay. Reduction of cellular oxidative stress was monitored by the formation of DCF fluorescent product and total glutathione (GSH) levels. The changes in glutathione-S-transferase (GST) activity and expression were determined by enzyme activity assay and Western blot analysis, respectively. Influence of CM on senescence-associated β-galactosidase activity (SA-β-gal) was also determined. The mechanisms of cytoprotection involved reduction of intracellular oxidative stress, maintaining GSH availability, and enhanced GST enzyme activity and expression. DOX-induced cellular senescence was also attenuated by long-term CM treatment. Thus, CM fruit juice can be promoted as functional fruit to protect cells from oxidative cell death, enhance the phase II GSTP enzyme activity, and decrease senescence phenotype population induced by cardiotoxic agent such as DOX. PMID:23401708

Tyrosine 8 contributes to catalysis but is not required for activity of rat liver glutathione S-transferase, 1-1.

PubMed Central

Wang, J.; Barycki, J. J.; Colman, R. F.

1996-01-01

Reaction of rat liver glutathione S-transferase, isozyme 1-1, with 4-(fluorosulfonyl)benzoic acid (4-FSB), a xenobiotic substrate analogue, results in a time-dependent inactivation of the enzyme to a final value of 35% of its original activity when assayed at pH 6.5 with 1-chloro-2,4-dinitrobenzene (CDNB) as substrate. The rate of inactivation exhibits a nonlinear dependence on the concentration of 4-FSB from 0.25 mM to 9 mM, characterized by a KI of 0.78 mM and kmax of 0.011 min-1. S-Hexylglutathione or the xenobiotic substrate analogue, 2,4-dinitrophenol, protects against inactivation of the enzyme by 4-FSB, whereas S-methylglutathione has little effect on the reaction. These experiments indicate that reaction occurs within the active site of the enzyme, probably in the binding site of the xenobiotic substrate, close to the glutathione binding site. Incorporation of [3,5-3H]-4-FSB into the enzyme in the absence and presence of S-hexylglutathione suggests that modification of one residue is responsible for the partial loss of enzyme activity. Tyr 8 and Cys 17 are shown to be the reaction targets of 4-FSB, but only Tyr 8 is protected against 4-FSB by S-hexylglutathione. DTT regenerates cysteine from the reaction product of cysteine and 4-FSB, but does not reactivate the enzyme. These results show that modification of Tyr 8 by 4-FSB causes the partial inactivation of the enzyme. The Michaelis constants for various substrates are not changed by the modification of the enzyme. The pH dependence of the enzyme-catalyzed reaction of glutathione with CDNB for the modified enzyme, as compared with the native enzyme, reveals an increase of about 0.9 in the apparent pKa, which has been interpreted as representing the ionization of enzyme-bound glutathione; however, this pKa of about 7.4 for modified enzyme remains far below the pK of 9.1 for the -SH of free glutathione. Previously, it was considered that Tyr 8 was essential for GST catalysis. In contrast, we conclude that

Reactive metabolites and antioxidant gene polymorphisms in Type 2 diabetes mellitus☆

PubMed Central

Banerjee, Monisha; Vats, Pushpank

2013-01-01

Type 2 diabetes mellitus (T2DM), by definition is a heterogeneous, multifactorial, polygenic syndrome which results from insulin receptor dysfunction. It is an outcome of oxidative stress caused by interactions of reactive metabolites (RMs) interactions with lipids, proteins and other mechanisms of human body. Production of RMs mainly superoxide (O2−) has been found in a variety of predominating cellular enzyme systems including NAD(P)H oxidase, xanthine oxidase (XO), cyclooxygenase (COX), uncoupled endothelial nitric oxide synthase (eNOS) and myeloperoxidase (MPO). The four main RM related molecular mechanisms are: increased polyol pathway flux; increased advanced glycation end-product (AGE) formation; activation of protein kinase C (PKC) isoforms and increased hexosamine pathway flux which have been implicated in glucose-mediated vascular damage. Superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione-S-transferase (GST), nitric oxide synthase (NOS) are antioxidant enzymes involved in scavenging RMs in normal individuals. Functional polymorphisms of these antioxidant enzymes have been reported to be involved in pathogenesis of T2DM individuals. The low levels of antioxidant enzymes or their non-functionality results in excessive RMs which initiate stress related pathways thereby leading to insulin resistance and T2DM. An attempt has been made to review the role of RMs and antioxidant enzymes in oxidative stress resulting in T2DM. PMID:25460725

Prognostic significance of the null genotype of glutathione S-transferase-T1 in patients with acute myeloid leukemia: increased early death after chemotherapy.

PubMed

Naoe, T; Tagawa, Y; Kiyoi, H; Kodera, Y; Miyawaki, S; Asou, N; Kuriyama, K; Kusumoto, S; Shimazaki, C; Saito, K; Akiyama, H; Motoji, T; Nishimura, M; Shinagawa, K; Ueda, R; Saito, H; Ohno, R

2002-02-01

We investigated the prognostic significance of genetic polymorphism in glutathione-S transferase mu 1 (GSTM1), glutathione-S transferase theta 1 (GSTT1), NAD(P)H:quinone oxidoreductase (NQO1) and myeloperoxidase (MPO), the products of which are associated with drug metabolism as well as with detoxication, in 193 patients with de novo acute myeloid leukemia (AML) other than M3. Of the patients, 64.2% were either homozygous or heterozygous for GSTT1 (GSTT1(+)), while 35.8% showed homozygous deletions of GSTT1 (GSTT1(-)). The GSTT1(-) group had a worse prognosis than the GSTT1(+) group (P = 0.04), whereas other genotypes did not affect the outcome. Multivariate analysis revealed that GSTT1(-) was an independent prognostic factor for overall survival (relative risk: 1.53; P = 0.026) but not for disease-free survival of 140 patients who achieved complete remission (CR). The rate of early death after the initiation of chemotherapy was higher in the GSTT1(-) group than the GSTT1(+) group (within 45 days after initial chemotherapy, P = 0.073; within 120 days, P = 0.028), whereas CR rates and relapse frequencies were similar. The null genotype of GSTT1 might be associated with increased toxicity after chemotherapy.

Is Increased Susceptibility to Balkan Endemic Nephropathy in Carriers of Common GSTA1 (*A/*B) Polymorphism Linked with the Catalytic Role of GSTA1 in Ochratoxin A Biotransformation? Serbian Case Control Study and In Silico Analysis

PubMed Central

Reljic, Zorica; Zlatovic, Mario; Savic-Radojevic, Ana; Pekmezovic, Tatjana; Djukanovic, Ljubica; Matic, Marija; Pljesa-Ercegovac, Marija; Mimic-Oka, Jasmina; Opsenica, Dejan; Simic, Tatjana

2014-01-01

Although recent data suggest aristolochic acid as a putative cause of Balkan endemic nephropathy (BEN), evidence also exists in favor of ochratoxin A (OTA) exposure as risk factor for the disease. The potential role of xenobiotic metabolizing enzymes, such as the glutathione transferases (GSTs), in OTA biotransformation is based on OTA glutathione adducts (OTHQ-SG and OTB-SG) in blood and urine of BEN patients. We aimed to analyze the association between common GSTA1, GSTM1, GSTT1, and GSTP1 polymorphisms and BEN susceptibility, and thereafter performed an in silico simulation of particular GST enzymes potentially involved in OTA transformations. GSTA1, GSTM1, GSTT1 and GSTP1 genotypes were determined in 207 BEN patients and 138 non-BEN healthy individuals from endemic regions by polymerase chain reaction (PCR). Molecular modeling in silico was performed for GSTA1 protein. Among the GST polymorphisms tested, only GSTA1 was significantly associated with a higher risk of BEN. Namely, carriers of the GSTA1*B gene variant, associated with lower transcriptional activation, were at a 1.6-fold higher BEN risk than those carrying the homozygous GSTA1*A/*A genotype (OR = 1.6; p = 0.037). In in silico modeling, we found four structures, two OTB-SG and two OTHQ-SG, bound in a GSTA1 monomer. We found that GSTA1 polymorphism was associated with increased risk of BEN, and suggested, according to the in silico simulation, that GSTA1-1 might be involved in catalyzing the formation of OTHQ-SG and OTB-SG conjugates. PMID:25111321

Glutathione S-Transferase P-Mediated Protein S-Glutathionylation of Resident Endoplasmic Reticulum Proteins Influences Sensitivity to Drug-Induced Unfolded Protein Response

PubMed Central

Ye, Zhi-Wei; Zhang, Jie; Ancrum, Tiffany; Manevich, Yefim; Townsend, Danyelle M.

2017-01-01

Abstract Aims: S-glutathionylation of cysteine residues, catalyzed by glutathione S-transferase Pi (GSTP), alters structure/function characteristics of certain targeted proteins. Our goal is to characterize how S-glutathionylation of proteins within the endoplasmic reticulum (ER) impact cell sensitivity to ER-stress inducing drugs. Results: We identify GSTP to be an ER-resident protein where it demonstrates both chaperone and catalytic functions. Redox based proteomic analyses identified a cluster of proteins cooperatively involved in the regulation of ER stress (immunoglobulin heavy chain-binding protein [BiP], protein disulfide isomerase [PDI], calnexin, calreticulin, endoplasmin, sarco/endoplasmic reticulum Ca2+-ATPase [SERCA]) that individually co-immunoprecipitated with GSTP (implying protein complex formation) and were subject to reactive oxygen species (ROS) induced S-glutathionylation. S-glutathionylation of each of these six proteins was attenuated in cells (liver, embryo fibroblasts or bone marrow dendritic) from mice lacking GSTP (Gstp1/p2−/−) compared to wild type (Gstp1/p2+/+). Moreover, Gstp1/p2−/− cells were significantly more sensitive to the cytotoxic effects of the ER-stress inducing drugs, thapsigargin (7-fold) and tunicamycin (2-fold). Innovation: Within the family of GST isozymes, GSTP has been ascribed the broadest range of catalytic and chaperone functions. Now, for the first time, we identify it as an ER resident protein that catalyzes S-glutathionylation of critical ER proteins within this organelle. Of note, this can provide a nexus for linkage of redox based signaling and pathways that regulate the unfolded protein response (UPR). This has novel importance in determining how some drugs kill cancer cells. Conclusions: Contextually, these results provide mechanistic evidence that GSTP can exert redox regulation in the oxidative ER environment and indicate that, within the ER, GSTP influences the cellular consequences of the UPR

Simulation of interindividual differences in inactivation of reactive para-benzoquinone imine metabolites of diclofenac by glutathione S-transferases in human liver cytosol.

PubMed

den Braver, Michiel W; Zhang, Yongjie; Venkataraman, Harini; Vermeulen, Nico P E; Commandeur, Jan N M

2016-07-25

Diclofenac is a widely prescribed NSAID that causes severe idiosyncratic drug induced liver injury (IDILI) in a small part of the patient population. Formation of protein-reactive metabolites is considered to play a role in the development of diclofenac-induced IDILI. Therefore, a high hepatic activity of enzymes involved in bioactivation of diclofenac is expected to increase the risk for liver injury. However, the extent of covalent protein binding may also be determined by activity of protective enzymes, such as glutathione S-transferases (GSTs). This is supported by an association study in which a correlation was found between NSAID-induced IDILI and the combined null genotypes of GSTM1 and GSTT1. In the present study, the activity of 10 different recombinant human GSTs in inactivation of protein-reactive quinoneimine (QI) metabolites of diclofenac was tested. Both at low and high GSH concentrations, high activities of GSTA1-1, A2-2, A3-3, M1-1, M3-3 and P1-1 in the inactivation of these QIs were found. By using the expression levels of GSTs in livers of 22 donors, a 6-fold variation in GST-dependent inactivation of reactive diclofenac metabolites was predicted. Moreover, it was shown in vitro that GSTs can strongly increase the efficiency of GSH to protect against the alkylation of the model thiol N-acetylcysteine by reactive diclofenac metabolites. The results of this study demonstrate that variability of GST expression may significantly contribute to the inter-individual differences in susceptibility to diclofenac-induced liver injury. In addition, expression levels of GSTs in in vitro models for hepatotoxicity may be important factors determining sensitivity to diclofenac cytotoxicity. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Regulation of Endothelial Permeability by Glutathione S-Transferase Pi Against Actin Polymerization.

PubMed

Yang, Yang; Yin, Fangyuan; Hang, Qiyun; Dong, Xiaoliang; Chen, Jiao; Li, Ling; Cao, Peng; Yin, Zhimin; Luo, Lan

2018-01-01

Inflammation-induced injury of the endothelial barrier occurs in several pathological conditions, including atherosclerosis, ischemia, and sepsis. Endothelial cytoskeleton rearrangement is an important pathological mechanism by which inflammatory stimulation triggers an increase of vascular endothelial permeability. However, the mechanism maintaining endothelial cell barrier function against inflammatory stress is not fully understood. Glutathione S-transferase pi (GSTpi) exists in various types of cells and protects them against different stresses. In our previous study, GSTpi was found to act as a negative regulator of inflammatory responses. We used a Transwell permeability assay to test the influence of GSTpi and its transferase activity on the increase of endothelial permeability induced by tumor necrosis factor alpha (TNF-α). TNF-α-induced actin remodeling and the influence of GSTpi were observed by using laser confocal microscopy. Western blotting was used to test the influence of GSTpi on TNF-α-activated p38 mitogen-activated protein kinase (MAPK)/MK2/heat shock protein 27 (HSP27). GSTpi reduced TNF-α-induced stress fiber formation and endothelial permeability increase by restraining actin cytoskeleton rearrangement, and this reduction was unrelated to its transferase activity. We found that GSTpi inhibited p38MAPK phosphorylation by directly binding p38 and influenced downstream substrate HSP27-induced actin remodeling. GSTpi inhibited TNF-α-induced actin remodeling, stress fiber formation and endothelial permeability increase by inhibiting the p38MAPK/HSP27 signaling pathway. © 2018 The Author(s). Published by S. Karger AG, Basel.

Glutathione transferases, regulators of cellular metabolism and physiology.

PubMed

Board, Philip G; Menon, Deepthi

2013-05-01

The cytosolic glutathione transferases (GSTs) comprise a super family of proteins that can be categorized into multiple classes with a mixture of highly specific and overlapping functions. The review covers the genetics, structure and function of the human cytosolic GSTs with particular attention to their emerging roles in cellular metabolism. All the catalytically active GSTs contribute to the glutathione conjugation or glutathione dependant-biotransformation of xenobiotics and many catalyze glutathione peroxidase or thiol transferase reactions. GSTs also catalyze glutathione dependent isomerization reactions required for the synthesis of several prostaglandins and steroid hormones and the catabolism of tyrosine. An increasing body of work has implicated several GSTs in the regulation of cell signaling pathways mediated by stress-activated kinases like Jun N-terminal kinase. In addition, some members of the cytosolic GST family have been shown to form ion channels in intracellular membranes and to modulate ryanodine receptor Ca(2+) channels in skeletal and cardiac muscle. In addition to their well established roles in the conjugation and biotransformation of xenobiotics, GSTs have emerged as significant regulators of pathways determining cell proliferation and survival and as regulators of ryanodine receptors that are essential for muscle function. This article is part of a Special Issue entitled Cellular functions of glutathione. Copyright © 2012 Elsevier B.V. All rights reserved.

Identification and characterization of an Apis cerana cerana Delta class glutathione S-transferase gene ( AccGSTD) in response to thermal stress

NASA Astrophysics Data System (ADS)

Yan, Huiru; Jia, Haihong; Wang, Xiuling; Gao, Hongru; Guo, Xingqi; Xu, Baohua

2013-02-01

Glutathione S-transferases (GSTs) are members of a multifunctional enzyme super family that plays a pivotal role in both insecticide resistance and protection against oxidative stress. In this study, we identified a single-copy gene, AccGSTD, as being a Delta class GST in the Chinese honey bee ( Apis cerana cerana). A predicted antioxidant response element, CREB, was found in the 1,492-bp 5'-flanking region, suggesting that AccGSTD may be involved in oxidative stress response pathways. Real-time PCR and immunolocalization studies demonstrated that AccGSTD exhibited both developmental- and tissue-specific expression patterns. During development, AccGSTD transcript was increased in adults. The AccGSTD expression level was the highest in the honey bee brain. Thermal stress experiments demonstrated that AccGSTD could be significantly upregulated by temperature changes in a time-dependent manner. It is hypothesized that high expression levels might be due to the increased levels of oxidative stress caused by the temperature challenges. Additionally, functional assays of the recombinant AccGSTD protein revealed that AccGSTD has the capability to protect DNA from oxidative damage. Taken together, these data suggest that AccGSTD may be responsible for antioxidant defense in adult honey bees.

Arabidopsis Glutathione Transferases U24 and U25 Exhibit a Range of Detoxification Activities with the Environmental Pollutant and Explosive, 2,4,6-Trinitrotoluene1[C][W][OPEN

PubMed Central

Gunning, Vanda; Tzafestas, Kyriakos; Sparrow, Helen; Johnston, Emily J.; Brentnall, Andrew S.; Potts, Jennifer R.; Rylott, Elizabeth L.; Bruce, Neil C.

2014-01-01

The explosive 2,4,6-trinitrotoluene (TNT) is a major worldwide military pollutant. The presence of this toxic and highly persistent pollutant, particularly at military sites and former manufacturing facilities, presents various health and environmental concerns. Due to the chemically resistant structure of TNT, it has proven to be highly recalcitrant to biodegradation in the environment. Here, we demonstrate the importance of two glutathione transferases (GSTs), GST-U24 and GST-U25, from Arabidopsis (Arabidopsis thaliana) that are specifically up-regulated in response to TNT exposure. To assess the role of GST-U24 and GST-U25, we purified and characterized recombinant forms of both enzymes and demonstrated the formation of three TNT glutathionyl products. Importantly, GST-U25 catalyzed the denitration of TNT to form 2-glutathionyl-4,6-dinitrotoluene, a product that is likely to be more amenable to subsequent biodegradation in the environment. Despite the presence of this biochemical detoxification pathway in plants, physiological concentrations of GST-U24 and GST-U25 result in only a limited innate ability to cope with the levels of TNT found at contaminated sites. We demonstrate that Arabidopsis plants overexpressing GST-U24 and GST-U25 exhibit significantly enhanced ability to withstand and detoxify TNT, properties that could be applied for in planta detoxification of TNT in the field. The overexpressing lines removed significantly more TNT from soil and exhibited a corresponding reduction in glutathione levels when compared with wild-type plants. However, in the absence of TNT, overexpression of these GSTs reduces root and shoot biomass, and although glutathione levels are not affected, this effect has implications for xenobiotic detoxification. PMID:24733884

A covalent G-site inhibitor for glutathione S-transferase Pi (GSTP1-1).

PubMed

Shishido, Yuko; Tomoike, Fumiaki; Kimura, Yasuaki; Kuwata, Keiko; Yano, Takato; Fukui, Kenji; Fujikawa, Haruka; Sekido, Yoshitaka; Murakami-Tonami, Yuko; Kameda, Tomoshi; Shuto, Satoshi; Abe, Hiroshi

2017-10-10

We herein report the first covalent G-site-binding inhibitor for GST, GS-ESF (1), which irreversibly inhibited the GSTP 1-1 function. LC-MS/MS and X-ray structure analyses of the covalently linked GST-inhibitor complex suggested that 1 reacted with Tyr108 of GSTP 1-1 . The mechanism of covalent bond formation was discussed based on MD simulation results.

Global deletion of glutathione S-Transferase A4 exacerbates developmental nonalcoholic steatohepatitis

USDA-ARS?s Scientific Manuscript database

We established a mouse model of developmental nonalcoholic steatohepatitis (NASH) by feeding a high polyunsaturated fat liquid diet to female glutathione-S-transferase 4-4 (Gsta4-/-)/peroxisome proliferator activated receptor a (Ppara-/-) double knockout 129/SvJ mice for 12 weeks from weaning. We us...

Analysis of Polymorphisms in Genes (AGT, MTHFR, GPIIIa, and GSTP1) Associated with Hypertension, Thrombophilia and Oxidative Stress in Mestizo and Amerindian Populations of México

PubMed Central

Juárez-Velázquez, Rocio; Canto, Patricia; Canto-Cetina, Thelma; Rangel-Villalobos, Hector; Rosas-Vargas, Haydee; Rodríguez, Maricela; Canizales-Quinteros, Samuel; Velázquez Wong, Ana Claudia; Ordoñez-Razo, Rosa María; Vilchis-Dorantes, Guadalupe; Coral-Vázquez, Ramón Mauricio

2010-01-01

Several polymorphisms related to hypertension, thrombophilia, and oxidative stress has been associated with the development of cardiovascular disease. We analyzed the frequency of M235T angiotensinogen (AGT), A222V 5,10 methylenete-trahydrofolate reductase (MTHFR), L33P glycoprotein IIIa (GPIIIa), and I105V glutathione S-transferase P1 (GSTP1) polymorphisms in 285 individuals belonging to Mexican-Mestizo and five Amerindian population from México, by real time PCR allelic discrimination. Allele and genotype frequencies were compared using χ2 tests. All populations followed the Hardy Weinberg equilibrium for assay markers with the exception of the Triki, whose were in Hardy Weinberg dysequilibrium for the glutathione S-transferase P1 polymorphism. Interestingly, according to all the analyzed single nucleotide polymorphisms (SNPs), the Triki population was the most differentiated and homogeneous group of the six populations analyzed. A comparison of our data with those previously published for some Caucasian, Asian and Black populations showed quite significant differences. These differences were remarkable with all the Mexican populations having a lower frequency of the 105V allele of the glutathione S-transferase P1 and reduced occurrence of the 222A allele of the 5,10 methylenetetrahydrofolate reductase. Our results show the genetic diversity among different Mexican populations and with other racial groups. PMID:20592457

How arbuscular mycorrhizal fungi influence the defense system of sunflower during different abiotic stresses.

PubMed

Mayer, Zoltán; Duc, Nguyen Hong; Sasvári, Zita; Posta, Katalin

2017-12-01

The association between terrestrial plants and arbuscular mycorrhizal (AM) fungi is one of the most common and widespread mutualistic plant-fungi interaction. AM fungi are of beneficial effects on the water and nutrient uptake of plants and increase plant defense mechanisms to alleviate different stresses. The aim of this study was to determine the level of polyphenol oxidase (PPO), guaiacol peroxidase (POX) and glutathione S-transferase (GST) enzyme activities and to track the expression of glutathione S-transferase (GST) gene in plant-arbuscular mycorrhizal system under temperature- and mechanical stress conditions. Our results suggest that induced tolerance of mycorrhizal sunflower to high temperature may be attributed to the induction of GST, POX and PPO enzyme activities as well as to the elevated expression of GST. However, the degree of tolerance of the plant is significantly influenced by the age which is probably justified by the energy considerations.

Adsorption of GST-PI3Kgamma at the air-buffer interface and at substrate and nonsubstrate phospholipid monolayers.

PubMed

Hermelink, Antje; Kirsch, Cornelia; Klinger, Reinhard; Reiter, Gerald; Brezesinski, Gerald

2009-02-01

The recruitment of phosphoinositide 3-kinase gamma (PI3Kgamma) to the cell membrane is a crucial requirement for the initiation of inflammation cascades by second-messenger production. In addition to identifying other regulation pathways, it has been found that PI3Kgamma is able to bind phospholipids directly. In this study, the adsorption behavior of glutathione S-transferase (GST)-PI3Kgamma to nonsubstrate model phospholipids, as well as to commercially available substrate inositol phospholipids (phosphoinositides), was investigated by use of infrared reflection-absorption spectroscopy (IRRAS). The nonsubstrate phospholipid monolayers also yielded important information about structural requirements for protein adsorption. The enzyme did not interact with condensed zwitterionic or anionic monolayers; however, it could penetrate into uncompressed fluid monolayers. Compression to values above its equilibrium pressure led to a squeezing out and desorption of the protein. Protein affinity for the monolayer surface increased considerably when the lipid had an anionic headgroup and contained an arachidonoyl fatty acyl chain in sn-2 position. Similar results on a much higher level were observed with substrate phosphoinositides. No structural response of GST-PI3Kgamma to lipid interaction was detected by IRRAS. On the other hand, protein adsorption caused a condensing effect in phosphoinositide monolayers. In addition, the protein reduced the charge density at the interface probably by shifting the pK values of the phosphate groups attached to the inositol headgroups. Because of their strongly polar headgroups, an interaction of the inositides with the water molecules of the subphase can be expected. This interaction is disturbed by protein adsorption, causing the ionization state of the phosphates to change.

Adsorption of GST-PI3Kγ at the Air-Buffer Interface and at Substrate and Nonsubstrate Phospholipid Monolayers

PubMed Central

Hermelink, Antje; Kirsch, Cornelia; Klinger, Reinhard; Reiter, Gerald; Brezesinski, Gerald

2009-01-01

The recruitment of phosphoinositide 3-kinase γ (PI3Kγ) to the cell membrane is a crucial requirement for the initiation of inflammation cascades by second-messenger production. In addition to identifying other regulation pathways, it has been found that PI3Kγ is able to bind phospholipids directly. In this study, the adsorption behavior of glutathione S-transferase (GST)-PI3Kγ to nonsubstrate model phospholipids, as well as to commercially available substrate inositol phospholipids (phosphoinositides), was investigated by use of infrared reflection-absorption spectroscopy (IRRAS). The nonsubstrate phospholipid monolayers also yielded important information about structural requirements for protein adsorption. The enzyme did not interact with condensed zwitterionic or anionic monolayers; however, it could penetrate into uncompressed fluid monolayers. Compression to values above its equilibrium pressure led to a squeezing out and desorption of the protein. Protein affinity for the monolayer surface increased considerably when the lipid had an anionic headgroup and contained an arachidonoyl fatty acyl chain in sn-2 position. Similar results on a much higher level were observed with substrate phosphoinositides. No structural response of GST-PI3Kγ to lipid interaction was detected by IRRAS. On the other hand, protein adsorption caused a condensing effect in phosphoinositide monolayers. In addition, the protein reduced the charge density at the interface probably by shifting the pK values of the phosphate groups attached to the inositol headgroups. Because of their strongly polar headgroups, an interaction of the inositides with the water molecules of the subphase can be expected. This interaction is disturbed by protein adsorption, causing the ionization state of the phosphates to change. PMID:19186139

Meta- and Pooled Analysis of GSTP1 Polymorphism and Lung Cancer: A HuGE-GSEC Review

PubMed Central

Chen, Wei; Smith, Daryn W.; Benhamou, Simone; Bouchardy, Christine; Butkiewicz, Dorota; Fong, Kwun M.; Gené, Manuel; Hirvonen, Ari; Kiyohara, Chikako; Larsen, Jill E.; Lin, Pinpin; Raaschou-Nielsen, Ole; Povey, Andrew C.; Reszka, Edyta; Risch, Angela; Schneider, Joachim; Schwartz, Ann G.; Sorensen, Mette; To-Figueras, Jordi; Tokudome, Shinkan; Pu, Yuepu; Yang, Ping; Wenzlaff, Angela S.; Wikman, Harriet; Taioli, Emanuela

2009-01-01

Lung cancer is the most common cancer worldwide. Polymorphisms in genes associated with carcinogen metabolism may modulate risk of disease. Glutathione S-transferase pi (GSTP1) detoxifies polycyclic aromatic hydrocarbons found in cigarette smoke and is the most highly expressed glutathione S-transferase in lung tissue. A polymorphism in the GSTP1 gene, an A-to-G transition in exon 5 (Ile105Val, 313A → 313G), results in lower activity among individuals who carry the valine allele. The authors present a meta- and a pooled analysis of case-control studies that examined the association between this polymorphism in GSTP1 and lung cancer risk (27 studies, 8,322 cases and 8,844 controls and 15 studies, 4,282 cases and 5,032 controls, respectively). Overall, the meta-analysis found no significant association between lung cancer risk and the GSTP1 exon 5 polymorphism. In the pooled analysis, there was an overall association (odds ratio = 1.11, 95% confidence interval: 1.03, 1.21) between lung cancer and carriage of the GSTP1 Val/Val or Ile/Val genotype compared with those carrying the Ile/Ile genotype. Increased risk varied by histologic type in Asians. There appears to be evidence for interaction between amount of smoking, the GSTP1 exon 5 polymorphism, and risk of lung cancer in whites. PMID:19240225

Disinfection by-products exposure and intra-uterine growth restriction: do genetic polymorphisms of CYP2E1or deletion of GSTM1 or GSTT1 modify the association?

PubMed Central

Levallois, Patrick; Giguère, Yves; Nguile-Makao, Molière; Rodriguez, Manuel; Campagna, Céline; Tardif, Robert; Bureau, Alexandre

2016-01-01

Background Exposure to disinfection by-products (DBPs) during pregnancy was associated with reduced fetal growth. Genetic susceptibility might play a role, especially for genes encoding for the Cytochrome P450 (CYP2E1) and Glutathione S-Transferase (GST) enzymes, involved in metabolism and activation of DBPs. Few epidemiological studies evaluated these gene-environment interactions and their results were never replicated. Objective This study aims to examine interactions between trihalomethanes (THM) or haloacetic acids (HAA) exposure and genetic polymorphisms on small for gestational age (SGA) neonates by investigating single nucleotide polymorphisms (SNPs) in CYP2E1 gene and GSTM1 and GSTT1 deletions in mothers-children pairs. Methods A population-based case-control study of 1549 mothers and 1455 children was conducted on SGA and THM/HAA exposure. DNA was extracted from blood or saliva cells. Targeted SNPs and deletions were genotyped. Statistical interaction between SNPs/deletions and THMs or HAAs in utero exposure with regard to SGA occurrence was evaluated by unconditional logistic regression with control of potential confounders. Results Previously reported positive modification of the effect of THM uterine exposure by mothers or newborns CYP2E1 rs3813867 C allele or GSTM1 deletion was not replicated. However interactions with CYP2E1 rs117618383 and rs2515641 were observed but were not statistically significant after correction for multiple testing. Conclusions Previous positive interactions between THMs exposure and CYP2E1 and GSTM1 were not replicated but interactions with other CYP2E1 polymorphisms are reported. PMID:27107227

Disinfection by-products exposure and intra-uterine growth restriction: Do genetic polymorphisms of CYP2E1or deletion of GSTM1 or GSTT1 modify the association?

PubMed

Levallois, Patrick; Giguère, Yves; Nguile-Makao, Molière; Rodriguez, Manuel; Campagna, Céline; Tardif, Robert; Bureau, Alexandre

2016-01-01

Exposure to disinfection by-products (DBPs) during pregnancy was associated with reduced foetal growth. Genetic susceptibility might play a role, especially for genes encoding for the Cytochrome P450 (CYP2E1) and Glutathione S-Transferase (GST) enzymes, involved in metabolism and activation of DBPs. Few epidemiological studies evaluated these gene-environment interactions and their results were never replicated. This study aims to examine interactions between trihalomethanes (THM) or haloacetic acids (HAA) exposure and genetic polymorphisms on small for gestational age (SGA) neonates by investigating single nucleotide polymorphisms (SNPs) in CYP2E1 gene and GSTM1 and GSTT1 deletions in mothers-children pairs. A population-based case-control study of 1549 mothers and 1455 children was conducted on SGA and THM/HAA exposure. DNA was extracted from blood or saliva cells. Targeted SNPs and deletions were genotyped. Statistical interaction between SNPs/deletions and THMs or HAAs in utero exposure with regard to SGA occurrence was evaluated by unconditional logistic regression with control of potential confounders. Previously reported positive modification of the effect of THM uterine exposure by mothers or newborns CYP2E1 rs3813867 C allele or GSTM1 deletion was not replicated. However interactions with CYP2E1 rs117618383 and rs2515641 were observed but were not statistically significant after correction for multiple testing. Previous positive interactions between THMs exposure and CYP2E1 and GSTM1 were not replicated but interactions with other CYP2E1 polymorphisms are reported. Copyright © 2016 Elsevier Ltd. All rights reserved.

Variants of glutathione s-transferase pi 1 exhibit differential enzymatic activity and inhibition by heavy metals.

PubMed

Goodrich, Jaclyn M; Basu, Niladri

2012-06-01

Nonsynonymous single nucleotide polymorphisms in glutathione s-transferase pi 1 (GSTP1; Ile/Val 105, Ala/Val 114) have been associated with altered toxicant metabolism in epidemiological cohorts. We explored the impact of GSTP1 genotype on enzyme kinetics and heavy metal inhibition in vitro. Four GSTP1 allozymes (105/114: Ile/Ala, Val/Ala, Ile/Val, Val/Val) were expressed in and purified from Escherichia coli. Enzyme activity assays quantifying the rate of glutathione conjugation with 1-chloro-2,4-dinitrobenzene (CDNB) revealed significant differences in kinetic parameters depending on genotype (p<0.01). Allozymes with Ile105 had better catalytic efficiency and greater affinity for CDNB (mean ± SEM: Ile105 Ala114 K(m)=0.33 ± 0.07 mM vs. Val105 Ala114 K(m)=1.15 ± 0.07 mM). Inhibition of GSTP1 activity by heavy metals was assessed following treatment with mercury (inorganic-HgCl(2), methylmercury-MeHg), selenium, cadmium, lead, arsenic, and manganese. All allozymes were inhibited by HgCl(2) (IC(50) range: 24.1-172 μM), MeHg (93.9-480 μM), and selenium (43.7-62.8 μM). Genotype significantly influenced the potency of mercury with GSTP1 Ile105 Val114 the least sensitive and Val105 Ala114 the most sensitive to inhibition by HgCl(2) and MeHg. Overall, genotype of two nonsynonymous polymorphisms in GSTP1 influenced enzyme kinetics pertaining to an electrophilic substrate and inhibition by two mercury species. Published by Elsevier Ltd.

Variants of glutathione s-transferase pi 1 exhibit differential enzymatic activity and inhibition by heavy metals

PubMed Central

Goodrich, Jaclyn M.; Basu, Niladri

2012-01-01

Nonsynonymous single nucleotide polymorphisms in glutathione s-transferase pi 1 (GSTP1; Ile/Val 105, Ala/Val 114) have been associated with altered toxicant metabolism in epidemiological cohorts. We explored the impact of GSTP1 genotype on enzyme kinetics and heavy metal inhibition in vitro. Four GSTP1 allozymes (105/114: Ile/Ala, Val/Ala, Ile/Val, Val/Val) were expressed in and purified from E. coli. Enzyme activity assays quantifying the rate of glutathione conjugation with 1-chloro-2,4-dinitrobenzene (CDNB) revealed significant differences in kinetic parameters depending on genotype (p<0.01). Allozymes with Ile105 had better catalytic efficiency and greater affinity for CDNB (mean ±SEM: Ile105 Ala114 Km= 0.33±0.07 mM vs. Val105 Ala114 Km=1.15±0.07 mM). Inhibition of GSTP1 activity by heavy metals was assessed following treatment with mercury (inorganic- HgCl2, methylmercury- MeHg), selenium, cadmium, lead, arsenic, and manganese. All allozymes were inhibited by HgCl2 (IC50 range: 24.1–172 μM), MeHg (93.9–480 μM), and selenium (43.7–62.8 μM). Genotype significantly influenced the potency of mercury with GSTP1 Ile105 Val114 the least sensitive and Val105 Ala114 the most sensitive to inhibition by HgCl2 and MeHg. Overall, genotype of two nonsynonymous polymorphisms in GSTP1 influenced enzyme kinetics pertaining to an electrophilic substrate and inhibition by two mercury species. PMID:22401947

Glutathione S-transferase genes and the risk of type 2 diabetes mellitus: Role of sexual dimorphism, gene-gene and gene-smoking interactions in disease susceptibility.

PubMed

Azarova, Iuliia; Bushueva, Olga; Konoplya, Alexander; Polonikov, Alexey

2018-05-01

Compromised defense against reactive oxygen species (ROS) is considered important in the pathogenesis of type 2 diabetes mellitus (T2DM); therefore, genes encoding antioxidant defense enzymes may contribute to disease susceptibility. This study investigated whether polymorphisms in genes encoding glutathione S-transferase M1 (GSTM1), T1 (GSTT1), and P1 (GSTP1) jointly contribute to the risk of T2DM. In all, 1120 unrelated Russian subjects (600 T2DM patients, 520 age- and sex-matched healthy subjects), were recruited to the study. Genotyping was performed by multiplex polymerase chain reaction (PCR; del/del polymorphisms of GSTM1 and GSTT1) and TaqMan-based PCR (polymorphisms I105V and A114V of GSTP1). Plasma ROS and glutathione levels in study subjects were analyzed by fluorometric and colorimetric assays, respectively. Genotype del/del GSTT1 was significantly associated with the risk of T2DM (odds ratio [OR] 1.60, 95% confidence interval [CI] 1.17-2.21, P = 0.003). Gender-stratified analysis showed that the deletion genotypes of GSTM1 (OR 1.99, 95% CI 1.30-3.05; P = 0.0002, Q = 0.016) and GSTT1 (OR 2.23, 95% CI 1.22-4.09; P = 0.008, Q = 0.0216), as well as genotype 114A/V of GSTP1 (OR 2.85, 95% CI 1.44-5.62; P = 0.005, Q = 0.02) were associated with an increased risk of T2DM exclusively in males. Three genotype combinations (i.e. GSTM1+ × GSTT1+, GSTM1+ × GSTP1 114A/A and GSTT1+ × GSTP1 114A/A) showed significant associations with a decreased risk of T2DM in males. This study demonstrates, for the first time, that genes encoding glutathione S-transferases jointly contribute to the risk of T2DM, and that their effects on disease susceptibility are gender specific. © 2017 Ruijin Hospital, Shanghai Jiaotong University School of Medicine and John Wiley & Sons Australia, Ltd.

Fish biomarkers for environmental monitoring: An integrated model supporting enzyme activity and histopathological lesions

NASA Astrophysics Data System (ADS)

Neta, Raimunda Nonata Fortes Carvalho; Torres Junior, Audalio Rebelo

2014-10-01

We present a mathematical model describing the association between glutathione-S-transferase activity and brachial lesions in the catfish, Sciades herzbergii (Ariidae) from a polluted port. The catfish were sampled from a port known to be contaminated with heavy metals and organic compounds and from a natural reserve in São Marcos Bay, Brazil. Two biomarkers, hepatic glutathione S-transferase (GST) activity and histopathological lesions, in gills tissue were measured. The values for GST activity were modeled with the occurrence of branchial lesions by fitting a third order polynomial. Results from the mathematical model indicate that GST activity has a strong polynomial relationship with the occurrence of branchial lesions in both the wet and the dry seasons, but only at the polluted port site. The model developed in this study indicates that branchial and hepatic lesions are initiated when GST activity reaches 2.15 μmol min-1 mg protein-1. Beyond this limit, GST activity decreased to very low levels and irreversible histopathological lesions occurred. This mathematical model provides a realistic approach to analyze predictive biomarkers of environmental health status.

Correlation Between Iron and alpha and pi Glutathione-S-Transferase Levels in Humans

DTIC Science & Technology

2012-09-01

assays were performed as described in the Biotrin High Sensitivity Alpha GST EIA kit protocol. First, serum samples were diluted 1:10 with wash solution...immunosorbent assays were performed as described in the Biotrin Pi GST EIA kit protocol. First, plasma samples were diluted 1:5 with sample diluent...immunosorbent assays were performed as described in the AssayMax Human Transferrin ELISA kit protocol. First, serum samples were diluted 1:2000 with MIX

Isoenzyme-specific up-regulation of glutathione transferase and aldo-keto reductase mRNA expression by dietary quercetin in rat liver.

PubMed

Odbayar, Tseye-Oidov; Kimura, Toshinori; Tsushida, Tojiro; Ide, Takashi

2009-05-01

The impact of quercetin on the mRNA expression of hepatic enzymes involved in drug metabolism was evaluated with a DNA microarray and real-time PCR. Male Sprague-Dawley rats were fed an experimental diet containing either 0, 2.5, 5, 10, or 20 g/kg of quercetin for 15 days. The DNA microarray analysis of the gene expression profile in pooled RNA samples from rats fed diets containing 0, 5, and 20 g/kg of quercetin revealed genes of some isoenzymes of glutathione transferase (Gst) and aldo-keto reductase (Akr) to be activated by this flavonoid. Real-time PCR conducted with RNA samples from individual rats fed varying amounts of quercetin together with the microarray analysis showed that quercetin caused marked dose-dependent increases in the mRNA expression of Gsta3, Gstp1, and Gstt3. Some moderate increases were also noted in the mRNA expression of isoenzymes belonging to the Gstm class. Quercetin also dose-dependently increased the mRNA expression of Akr1b8 and Akr7a3. However, it did not affect the parameters of the other Gst and Akr isoenzymes. It is apparent that quercetin increases the mRNA expression of Gst and Akr involved in drug metabolism in an isoenzyme-specific manner. Inasmuch as Gst and Akr isoenzymes up-regulated in their gene expression are involved in the prevention and attenuation of cancer development, this consequence may account for the chemopreventive propensity of quercetin.

S-Nitrosation destabilizes glutathione transferase P1-1.

PubMed

Balchin, David; Stoychev, Stoyan H; Dirr, Heini W

2013-12-23

Protein S-nitrosation is a post-translational modification that regulates the function of more than 500 human proteins. Despite its apparent physiological significance, S-nitrosation is poorly understood at a molecular level. Here, we investigated the effect of S-nitrosation on the activity, structure, stability, and dynamics of human glutathione transferase P1-1 (GSTP1-1), an important detoxification enzyme ubiquitous in aerobes. S-Nitrosation at Cys47 and Cys101 reduces the activity of the enzyme by 94%. Circular dichroism spectroscopy, acrylamide quenching, and amide hydrogen-deuterium exchange mass spectrometry experiments indicate that the loss of activity is caused by the introduction of local disorder at the active site of GSTP1-1. Furthermore, the modification destabilizes domain 1 of GSTP1-1 against denaturation, smoothing the unfolding energy landscape of the protein and introducing a refolding defect. In contrast, S-nitrosation at Cys101 alone introduces a refolding defect in domain 1 but compensates by stabilizing the domain kinetically. These data elucidate the physical basis for the regulation of GSTP1-1 by S-nitrosation and provide general insight into the consequences of S-nitrosation on protein stability and dynamics.

Glutathione S-transferase P1 (GSTP1) directly influences platinum drug chemosensitivity in ovarian tumour cell lines.

PubMed

Sawers, L; Ferguson, M J; Ihrig, B R; Young, H C; Chakravarty, P; Wolf, C R; Smith, G

2014-09-09

Chemotherapy response in ovarian cancer patients is frequently compromised by drug resistance, possibly due to altered drug metabolism. Platinum drugs are metabolised by glutathione S-transferase P1 (GSTP1), which is abundantly, but variably expressed in ovarian tumours. We have created novel ovarian tumour cell line models to investigate the extent to which differential GSTP1 expression influences chemosensitivity. Glutathione S-transferase P1 was stably deleted in A2780 and expression significantly reduced in cisplatin-resistant A2780DPP cells using Mission shRNA constructs, and MTT assays used to compare chemosensitivity to chemotherapy drugs used to treat ovarian cancer. Differentially expressed genes in GSTP1 knockdown cells were identified by Illumina HT-12 expression arrays and qRT-PCR analysis, and altered pathways predicted by MetaCore (GeneGo) analysis. Cell cycle changes were assessed by FACS analysis of PI-labelled cells and invasion and migration compared in quantitative Boyden chamber-based assays. Glutathione S-transferase P1 knockdown selectively influenced cisplatin and carboplatin chemosensitivity (2.3- and 4.83-fold change in IC50, respectively). Cell cycle progression was unaffected, but cell invasion and migration was significantly reduced. We identified several novel GSTP1 target genes and candidate platinum chemotherapy response biomarkers. Glutathione S-transferase P1 has an important role in cisplatin and carboplatin metabolism in ovarian cancer cells. Inter-tumour differences in GSTP1 expression may therefore influence response to platinum-based chemotherapy in ovarian cancer patients.

Polymorphism in the intron 20 of porcine O-linked N-acetylglucosamine transferase

USDA-ARS?s Scientific Manuscript database

Objective: O-linked N-acetylglucosamine (O-GlcNAc) transferase (OGT) catalyzes the addition of O-GlcNAc and GlcNAcylation has extensive crosstalk with phosphorylation to regulate signaling and transcription. Pig OGT is located near the region of chromosome X that affects follicle stimulating hormone...

DNA BINDING POTENTIAL OF BROMODICHLOROMETHANE MEDIATED BY GLUTATHIONE S-TRANSFERASE THETA 1-1

EPA Science Inventory

DNA BINDING POTENTIAL OF BROMODICHLOROMETHANE MEDIATED BY GLUTATHIONE S-TRANSFERASE THETA 1-1. R A Pegram1 and M K Ross2. 2Curriculum in Toxicology, University of North Carolina, Chapel Hill, NC; 1Pharmacokinetics Branch, NHEERL, ORD, United States Environmental Protection Ag...

Polymorphisms in xenobiotic metabolizing enzymes and diet influence colorectal adenoma risk.

PubMed

Northwood, Emma L; Elliott, Faye; Forman, David; Barrett, Jennifer H; Wilkie, Murray J V; Carey, Francis A; Steele, Robert J C; Wolf, Roland; Bishop, Timothy; Smith, Gillian

2010-05-01

We have earlier shown that diet and xenobiotic metabolizing enzyme genotypes influence colorectal cancer risk, and now investigate whether similar associations are seen in patients with premalignant colorectal adenomas (CRA), recruited during the pilot phase of the Scottish Bowel Screening Programme. Nineteen polymorphisms in 13 genes [cytochrome P450 (P450), glutathione S-transferase (GST), N-acetyl transferase, quinone reductase (NQ01) and microsomal epoxide hydrolase (EPHX1) genes] were genotyped using multiplex PCR or Taqman-based allelic discrimination assays and analyzed in conjunction with diet, assessed by food frequency questionnaire, in a case-control study [317 CRA cases (308 cases genotyped), 296 controls]. Findings significant at a nominal 5% level are reported. CRA risk was inversely associated with fruit (P=0.02, test for trend) and vegetable (P=0.001, test for trend) consumption. P450 CYP2C9*3 heterozygotes had reduced CRA risk compared with homozygotes for the reference allele [odds ratio (OR): 0.60; 95% confidence interval (CI): 0.36-0.99], whereas CYP2D6*4 homozygotes (OR: 2.72; 95% CI: 1.18-6.27) and GSTM1 'null' individuals (OR: 1.43; 95% CI: 1.04-1.98) were at increased risk. The protective effect of fruit consumption was confined to GSTP1 (Ala114Val) reference allele homozygotes (OR: 0.49; 95% CI: 0.34-0.71, P=0.03 for interaction). CRA risk was not associated with meat consumption, although a significant interaction between red meat consumption and EPHX1 (His139Arg) genotype was noted (P=0.02 for interaction). We report the novel associations between P450 genotype and CRA risk, and highlight the risk association with GSTM1 genotype, common to our CRA and cancer case-control series. In addition, we report a novel modifying influence of GSTP1 genotype on dietary chemoprevention. These novel findings require independent confirmation.

Thiazolides inhibit growth and induce glutathione-S-transferase Pi (GSTP1)-dependent cell death in human colon cancer cells.

PubMed

Müller, Joachim; Sidler, Daniel; Nachbur, Ueli; Wastling, Jonathan; Brunner, Thomas; Hemphill, Andrew

2008-10-15

Thiazolides are a novel class of broad-spectrum anti-infective drugs with promising in vitro and in vivo activities against intracellular and extracellular protozoan parasites. The nitrothiazole-analogue nitazoxanide (NTZ; 2-acetolyloxy-N-(5-nitro 2-thiazolyl) benzamide) represents the thiazolide parent compound, and a number of bromo- and carboxy-derivatives with differing activities have been synthesized. Here we report that NTZ and the bromo-thiazolide RM4819, but not the carboxy-thiazolide RM4825, inhibited proliferation of the colon cancer cell line Caco2 and nontransformed human foreskin fibroblasts (HFF) at or below concentrations the compounds normally exhibit anti-parasitic activity. Thiazolides induced typical signs of apoptosis, such as nuclear condensation, DNA fragmentation and phosphatidylserine exposure. Interestingly, the apoptosis-inducing effect of thiazolides appeared to be cell cycle-dependent and induction of cell cycle arrest substantially inhibited the cell death-inducing activity of these compounds. Using affinity chromatography and mass spectrometry glutathione-S-transferase P1 (GSTP1) from the GST class Pi was identified as a major thiazolide-binding protein. GSTP1 expression was more than 10 times higher in the thiazolide-sensitive Caco2 cells than in the less sensitive HFF cells. The enzymatic activity of recombinant GSTP1 was strongly inhibited by thiazolides. Silencing of GSTP1 using siRNA rendered cells insensitive to RM4819, while overexpression of GSTP1 increased sensitivity to RM4819-induced cell death. Thiazolides may thus represent an interesting novel class of future cancer therapeutics.

Thr105Ile (rs11558538) polymorphism in the histamine-1-methyl-transferase (HNMT) gene and risk for restless legs syndrome.

PubMed

Jiménez-Jiménez, Félix Javier; García-Martín, Elena; Alonso-Navarro, Hortensia; Martínez, Carmen; Zurdo, Martín; Turpín-Fenoll, Laura; Millán-Pascual, Jorge; Adeva-Bartolomé, Teresa; Cubo, Esther; Navacerrada, Francisco; Rojo-Sebastián, Ana; Rubio, Lluisa; Ortega-Cubero, Sara; Pastor, Pau; Calleja, Marisol; Plaza-Nieto, José Francisco; Pilo-de-la-Fuente, Belén; Arroyo-Solera, Margarita; García-Albea, Esteban; Agúndez, José A G

2017-03-01

A recent meta-analysis suggests an association between the rs11558538 single nucleotide polymorphism in the histamine-N-methyl-transferase (HNMT) gene and the risk for Parkinson's disease. Based on the possible relationship between PD and restless legs syndrome (RLS), we tried to establish whether rs11558538 SNP is associated with the risk for RLS. We studied the genotype and allelic variant frequencies of HNMT rs11558538 SNP 205 RLS patients and 410 healthy controls using a TaqMan assay. The frequencies of the HNMT rs11558538 genotypes allelic variants were similar between RLS patients and controls, and were not influenced by gender, family history of RLS, or RLS severity. RLS patients carrying the genotype rs11558538TT had an earlier age at onset, but this finding was based on three subjects only. These results suggest a lack of major association between HNMT rs11558538 SNP and the risk for RLS.

A Tyrosine-Reactive Irreversible Inhibitor for Glutathione S-Transferase Pi (GSTP1)

PubMed Central

Crawford, L. A.; Weerapana, E.

2016-01-01

Glutathione S-Transferase Pi (GSTP1) mediates cellular defense against reactive electrophiles. Here, we report LAS17, a dichlorotriazine-containing compound that irreversibly inhibits GSTP1 and is selective for GSTP1 within cellular proteomes. Mass spectrometry and mutational studies identified Y108 as the site of modification, providing a unique mode of GSTP1 inhibition. PMID:27113843

A tyrosine-reactive irreversible inhibitor for glutathione S-transferase Pi (GSTP1).

PubMed

Crawford, L A; Weerapana, E

2016-05-24

Glutathione S-transferase Pi (GSTP1) mediates cellular defense against reactive electrophiles. Here, we report LAS17, a dichlorotriazine-containing compound that irreversibly inhibits GSTP1 and is selective for GSTP1 within cellular proteomes. Mass spectrometry and mutational studies identified Y108 as the site of modification, providing a unique mode of GSTP1 inhibition.

Functional Role of Tyr12 in the Catalytic Activity of Novel Zeta-like Glutathione S-transferase from Acidovorax sp. KKS102.

PubMed

Shehu, Dayyabu; Alias, Zazali

2018-05-19

Glutathione S-transferases (GSTs) are a family of enzymes that function in the detoxification of variety of electrophilic substrates. In the present work, we report a novel zeta-like GST (designated as KKSG9) from the biphenyl/polychlorobiphenyl degrading organism Acidovorax sp. KKS102. KKSG9 possessed low sequence similarity but similar biochemical properties to zeta class GSTs. Functional analysis showed that the enzyme exhibits wider substrate specificity compared to most zeta class GSTs by reacting with 1-chloro-2,4-dinitrobenzene (CDNB), p-nitrobenzyl chloride (NBC), ethacrynic acid (EA), hydrogen peroxide, and cumene hydroperoxide. The enzyme also displayed dehalogenation function against dichloroacetate, permethrin, and dieldrin. The functional role of Tyr12 was also investigated by site-directed mutagenesis. The mutant (Y12C) displayed low catalytic activity and dehalogenation function against all the substrates when compared with the wild type. Kinetic analysis using NBC and GSH as substrates showed that the mutant (Y12C) displayed a higher affinity for NBC when compared with the wild type, however, no significant change in GSH affinity was observed. These findings suggest that the presence of tyrosine residue in the motif might represent an evolutionary trend toward improving the catalytic activity of the enzyme. The enzyme as well could be useful in the bioremediation of various types of organochlorine pollutants.

Relationship between GSTM1 and GSTT1 polymorphisms and schizophrenia: a case-control study in a Tunisian population.

PubMed

Raffa, Monia; Lakhdar, Ramzi; Ghachem, Meriem; Barhoumi, Sana; Safar, Mohamed Taher; Bel Hadj Jrad, Besma; Haj Khelil, Amel; Kerkeni, Abdelhamid; Mechri, Anwar

2013-01-10

There is substantial evidence found in the literature that supports the fact that the presence of oxidative stress may play an important role in the pathophysiology of schizophrenia. The glutathione S-transferases (GSTs) forms one of the major detoxifying groups of enzymes responsible for eliminating products of oxidative stress. Interindividual differences observed in the metabolism of xenobiotics have been attributed to the genetic polymorphism of genes coding for enzymes involved in detoxification. Thus, in this study we investigated the association of glutathione S-transferase Mu-1 (GSTM1) and glutathione S-transferase theta-1 (GSTT1) gene deletion polymorphisms and schizophrenia in a Tunisian population. A case-control study including 138 schizophrenic patients and 123 healthy controls was enrolled. The GSTM1 and GSTT1 polymorphisms were analyzed by multiplex polymerase chain reaction (PCR). No association was found between the GSTM1 genotype and schizophrenia, whereas the prevalence of the GSTT1 active genotype was significantly higher in the schizophrenic patients (57.2%) than in the controls (45.5%) with (OR=0.6, IC 0.37-0.99, p=0.039). Thus, we noted a significant association between schizophrenia and GSTT1 active genotype. Furthermore, the combination of the GSTM1 and GSTT1 null genotypes showed a non-significant trend to an increased risk of schizophrenia. The present finding indicated that GSTT1 seems to be a candidate gene for susceptibility to schizophrenia in at least Tunisian population. Copyright © 2012 Elsevier B.V. All rights reserved.

Glutathione S-transferase P1 (GSTP1) directly influences platinum drug chemosensitivity in ovarian tumour cell lines

PubMed Central

Sawers, L; Ferguson, M J; Ihrig, B R; Young, H C; Chakravarty, P; Wolf, C R; Smith, G

2014-01-01

Background: Chemotherapy response in ovarian cancer patients is frequently compromised by drug resistance, possibly due to altered drug metabolism. Platinum drugs are metabolised by glutathione S-transferase P1 (GSTP1), which is abundantly, but variably expressed in ovarian tumours. We have created novel ovarian tumour cell line models to investigate the extent to which differential GSTP1 expression influences chemosensitivity. Methods: Glutathione S-transferase P1 was stably deleted in A2780 and expression significantly reduced in cisplatin-resistant A2780DPP cells using Mission shRNA constructs, and MTT assays used to compare chemosensitivity to chemotherapy drugs used to treat ovarian cancer. Differentially expressed genes in GSTP1 knockdown cells were identified by Illumina HT-12 expression arrays and qRT–PCR analysis, and altered pathways predicted by MetaCore (GeneGo) analysis. Cell cycle changes were assessed by FACS analysis of PI-labelled cells and invasion and migration compared in quantitative Boyden chamber-based assays. Results: Glutathione S-transferase P1 knockdown selectively influenced cisplatin and carboplatin chemosensitivity (2.3- and 4.83-fold change in IC50, respectively). Cell cycle progression was unaffected, but cell invasion and migration was significantly reduced. We identified several novel GSTP1 target genes and candidate platinum chemotherapy response biomarkers. Conclusions: Glutathione S-transferase P1 has an important role in cisplatin and carboplatin metabolism in ovarian cancer cells. Inter-tumour differences in GSTP1 expression may therefore influence response to platinum-based chemotherapy in ovarian cancer patients. PMID:25010864

Simulation studies of GST phase change alloys

NASA Astrophysics Data System (ADS)

Martyna, Glenn

2008-03-01

In order to help drive post-Moore's Law technology development, switching processes involving novel materials, in particular, GeSbTe (GST) alloys are being investigated for use in memory and eFuse applications. An anneal/quench thermal process crystallizes/amorphosizes a GST alloy which then has a low/high resistance and thereby forms a readable/writeable bit; for example, a ``one'' might be the low resistance, conducting crystalline state and a ``zero'' might be the high resistance, glassy state. There are many open questions about the precise nature of the structural transitions and the coupling to electronic structure changes. Computational and experimental studies of the effect of pressure on the GST materials were initiated in order to probe the physics behind the thermal switching process. A new pathway to reversible phase change involving pressure-induced structural metal insulator transitions was discovered. In a binary GS system, a room-temperature, direct, pressure-induced transformation from the high resistance amorphous phase to the low resistance crystalline phase was observed experimentally while the reverse process under tensile load was demonstrated via ab initio MD simulations performed on IBM's Blue Gene/L enabled by massively parallel software. Pressure induced transformations of the ternary material GST-225 (Ge2Sb2Te5) were, also, examined In the talk, the behavior of the two systems will be compared and insight into the nature of the phase change given.

Fluorescein diacetate (FDA) and its analogue as substrates for Pi-class glutathione S-transferase (GSTP1) and their biological application.

PubMed

Fujikawa, Yuuta; Nampo, Taiki; Mori, Masaya; Kikkawa, Manami; Inoue, Hideshi

2018-03-01

Pi class glutathione S-transferase (GSTP1) is highly expressed in various cancerous cells and pre-neoplastic legions, where it is involved in apoptotic resistance or metabolism of several anti-tumour chemotherapeutics. Therefore, GSTP1 is a marker of malignant and pre-malignant cells and is a promising target for visualization and drug development. Here we demonstrate that fluorescein diacetate (FDA), a fluorescent probe used for vital staining, is a fluorescently activated by esterolytic activity of human GSTP1 (hGSTP1) selectively among various cytosolic GSTs. Fluorescence activation of FDA susceptible to GST inhibitors was observed in MCF7 cells exogenously overexpressing hGSTP1, but not in cells overexpressing hGSTA1 or hGSTM1. Inhibitor-sensitive fluorescence activation was also observed in several cancer cell lines endogenously expressing GSTP1, suggesting that GSTP1 is involved in FDA esterolysis in these cells. Among the FDA derivatives examined, FOMe-Ac, the acetyl ester of fluorescein O-methyl ether, was found to be a potential reporter for GSH-dependent GSTP1 activity as well as for carboxylesterase activity. Since GSTP1 is highly expressed in various types of cancer cells compared to their normal counterparts, improving the fluorogenic substrates to be more selective to the esterolysis activity of GSTP1 rather than carboxylesterases should lead to development of tools for detecting GSTP1-overexpressing cancer cells and investigating the biological functions of GSTP1. Copyright © 2017 Elsevier B.V. All rights reserved.

An Application of General System Theory (GST) to Group Therapy.

ERIC Educational Resources Information Center

Matthews, Charles O.

1992-01-01

Demonstrates the compatibility of General System Theory (GST) with the traditional counseling literature in explicating a therapy group's progression through Tuckman's (1965, 1977) developmental stages (forming, storming, norming, performing, and adjourning). Description uses both traditional group literature and GST concepts. (Author/NB)

Identification of Glutathione S-Transferase Pi as a Protein Involved in Parkinson Disease Progression

PubMed Central

Shi, Min; Bradner, Joshua; Bammler, Theo K.; Eaton, David L.; Zhang, JianPeng; Ye, ZuCheng; Wilson, Angela M.; Montine, Thomas J.; Pan, Catherine; Zhang, Jing

2009-01-01

Parkinson disease (PD) typically affects the cortical regions during the later stages of disease, with neuronal loss, gliosis, and formation of diffuse cortical Lewy bodies in a significant portion of patients with dementia. To identify novel proteins involved in PD progression, we prepared synaptosomal fractions from the frontal cortices of pathologically verified PD patients at different stages along with age-matched controls. Protein expression profiles were compared using a robust quantitative proteomic technique. Approximately 100 proteins displayed significant differences in their relative abundances between PD patients at various stages and controls; three of these proteins were validated using independent techniques. One of the confirmed proteins, glutathione S-transferase Pi, was further investigated in cellular models of PD, demonstrating that its level was intimately associated with several critical cellular processes that are directly related to neurodegeneration in PD. These results have, for the first time, suggested that the levels of glutathione S-transferase Pi may play an important role in modulating the progression of PD. PMID:19498008

Characterization of glutathione transferases involved in the pathogenicity of Alternaria brassicicola.

PubMed

Calmes, Benoit; Morel-Rouhier, Mélanie; Bataillé-Simoneau, Nelly; Gelhaye, Eric; Guillemette, Thomas; Simoneau, Philippe

2015-06-18

Glutathione transferases (GSTs) represent an extended family of multifunctional proteins involved in detoxification processes and tolerance to oxidative stress. We thus anticipated that some GSTs could play an essential role in the protection of fungal necrotrophs against plant-derived toxic metabolites and reactive oxygen species that accumulate at the host-pathogen interface during infection. Mining the genome of the necrotrophic Brassica pathogen Alternaria brassicicola for glutathione transferase revealed 23 sequences, 17 of which could be clustered into the main classes previously defined for fungal GSTs and six were 'orphans'. Five isothiocyanate-inducible GSTs from five different classes were more thoroughly investigated. Analysis of their catalytic properties revealed that two GSTs, belonging to the GSTFuA and GTT1 classes, exhibited GSH transferase activity with isothiocyanates (ITC) and peroxidase activity with cumene hydroperoxide, respectively. Mutant deficient for these two GSTs were however neither more susceptible to ITC nor less aggressive than the wild-type parental strain. By contrast mutants deficient for two other GSTs, belonging to the Ure2pB and GSTO classes, were distinguished by their hyper-susceptibility to ITC and low aggressiveness against Brassica oleracea. In particular AbGSTO1 could participate in cell tolerance to ITC due to its glutathione-dependent thioltransferase activity. The fifth ITC-inducible GST belonged to the MAPEG class and although it was not possible to produce the soluble active form of this protein in a bacterial expression system, the corresponding deficient mutant failed to develop normal symptoms on host plant tissues. Among the five ITC-inducible GSTs analyzed in this study, three were found essential for full aggressiveness of A. brassicicola on host plant. This, to our knowledge is the first evidence that GSTs might be essential virulence factors for fungal necrotrophs.

GSTA1 diplotypes affect busulfan clearance and toxicity in children undergoing allogeneic hematopoietic stem cell transplantation: a multicenter study.

PubMed

Ansari, Marc; Curtis, Patricia Huezo-Diaz; Uppugunduri, Chakradhara Rao S; Rezgui, Mohammed Aziz; Nava, Tiago; Mlakar, Vid; Lesne, Laurence; Théoret, Yves; Chalandon, Yves; Dupuis, Lee L; Schechter, Tao; Bartelink, Imke H; Boelens, Jaap J; Bredius, Robbert; Dalle, Jean-Hugues; Azarnoush, Saba; Sedlacek, Petr; Lewis, Victor; Champagne, Martin; Peters, Christina; Bittencourt, Henrique; Krajinovic, Maja

2017-10-31

Busulfan (BU) dose adjustment following therapeutic drug monitoring contributes to better outcome of hematopoietic stem cell transplantation (HSCT). Further improvement could be achieved through genotype-guided BU dose adjustments. To investigate this aspect, polymorphism within glutathione S transferase genes were assessed. Particularly, promoter haplotypes of the glutathione S transferase A1 ( GSTA1 ) were evaluated in vitro, with reporter gene assays and clinically, in a pediatric multi-center study (N =138) through association with BU pharmacokinetics (PK) and clinical outcomes. Promoter activity significantly differed between the GSTA1 haplotypes (p<0.001) supporting their importance in capturing PK variability. Four GSTA1 diplotype groups that significantly correlated with clearance (p=0.009) were distinguished. Diplotypes underlying fast and slow metabolizing capacity showed higher and lower BU clearance (ml/min/kg), respectively. GSTA1 diplotypes with slow metabolizing capacity were associated with higher incidence of sinusoidal obstruction syndrome, acute graft versus host disease and combined treatment-related toxicity (p<0.0005). Among other GST genes investigated, GSTP1 313GG correlated with acute graft versus host disease grade 1-4 (p=0.01) and GSTM1 non-null genotype was associated with hemorrhagic cystitis (p=0.003). This study further strengthens the hypothesis that GST diplotypes/genotypes could be incorporated into already existing population pharmacokinetic models for improving first BU dose prediction and HSCT outcomes. (N o Clinicaltrials.gov identifier: NCT01257854. Registered 8 December 2010, retrospectively registered).

GSTA1 diplotypes affect busulfan clearance and toxicity in children undergoing allogeneic hematopoietic stem cell transplantation: a multicenter study

PubMed Central

Ansari, Marc; Curtis, Patricia Huezo-Diaz; Uppugunduri, Chakradhara Rao S.; Rezgui, Mohammed Aziz; Nava, Tiago; Mlakar, Vid; Lesne, Laurence; Théoret, Yves; Chalandon, Yves; Dupuis, Lee L.; Schechter, Tao; Bartelink, Imke H.; Boelens, Jaap J.; Bredius, Robbert; Dalle, Jean-Hugues; Azarnoush, Saba; Sedlacek, Petr; Lewis, Victor; Champagne, Martin; Peters, Christina; Bittencourt, Henrique; Krajinovic, Maja

2017-01-01

Busulfan (BU) dose adjustment following therapeutic drug monitoring contributes to better outcome of hematopoietic stem cell transplantation (HSCT). Further improvement could be achieved through genotype-guided BU dose adjustments. To investigate this aspect, polymorphism within glutathione S transferase genes were assessed. Particularly, promoter haplotypes of the glutathione S transferase A1 (GSTA1) were evaluated in vitro, with reporter gene assays and clinically, in a pediatric multi-center study (N =138) through association with BU pharmacokinetics (PK) and clinical outcomes. Promoter activity significantly differed between the GSTA1 haplotypes (p<0.001) supporting their importance in capturing PK variability. Four GSTA1 diplotype groups that significantly correlated with clearance (p=0.009) were distinguished. Diplotypes underlying fast and slow metabolizing capacity showed higher and lower BU clearance (ml/min/kg), respectively. GSTA1 diplotypes with slow metabolizing capacity were associated with higher incidence of sinusoidal obstruction syndrome, acute graft versus host disease and combined treatment-related toxicity (p<0.0005). Among other GST genes investigated, GSTP1 313GG correlated with acute graft versus host disease grade 1-4 (p=0.01) and GSTM1 non-null genotype was associated with hemorrhagic cystitis (p=0.003). This study further strengthens the hypothesis that GST diplotypes/genotypes could be incorporated into already existing population pharmacokinetic models for improving first BU dose prediction and HSCT outcomes. (No Clinicaltrials.gov identifier: NCT01257854. Registered 8 December 2010, retrospectively registered). PMID:29207608

Production of monoclonal antibodies and development of a quantitative immuno-polymerase chain reaction assay to detect and quantify recombinant Glutathione S-transferase.

PubMed

Abud, J E; Luque, E H; Ramos, J G; Rodriguez, H A

2017-07-01

GST-tagged proteins are important tools for the production of recombinant proteins. Removal of GST tag from its fusion protein, frequently by harsh chemical treatments or proteolytic methods, is often required. Thus, the monitoring of the proteins in tag-free form requires a significant effort to determine the remnants of GST during purification process. In the present study, we developed both a conventional enzyme-linked immunosorbent assay (ELISA) and an immuno-polymerase chain reaction (IPCR) assay, both specific for detection of recombinant GST (rGST). rGST was expressed in Escherichia coli JM109, using a pGEX4T-3 vector, and several anti-rGST monoclonal antibodies were generated using hybridoma technology. Two of these were rationally selected as capture and detection antibodies, allowing the development of a sandwich ELISA with a limit of detection (LOD) of 0.01 μg/ml. To develop the rGST-IPCR assay, we selected "Universal-IPCR" format, comprising the biotin-avidin binding as the coupling system. In addition, the rGST-IPCR was developed in standard PCR tubes, and the surface adsorption of antibodies on PCR tubes, the optimal neutravidin concentrations, the generation of a reporter DNA and the concentration effect were studied and determined. Under optimized assay conditions, the rGST-IPCR assay provided a 100-fold increase in the LOD as well as an expanded working range, in comparison with rGST-ELISA. The proposed method exhibited great potentiality for application in several fields in which measurement of very low levels of GST is necessary, and might provide a model for other IPCR assays. Copyright © 2017 Elsevier Inc. All rights reserved.

The dyad palindromic glutathione transferase P enhancer binds multiple factors including AP1.

PubMed Central

Diccianni, M B; Imagawa, M; Muramatsu, M

1992-01-01

Glutathione Transferase P (GST-P) gene expression is dominantly regulated by an upstream enhancer (GPEI) consisting of a dyad of palindromically oriented imperfect TPA (12-O-tetradecanoyl-phorbol-13-acetate)-responsive elements (TRE). GPEI is active in AP1-lacking F9 cells as well in AP1-containing HeLa cells. Despite GPEI's similarity to a TRE, c-jun co-transfection has only a minimal effect on transactivation. Antisense c-jun and c-fos co-transfection experiments further demonstrate the lack of a role for AP1 in GPEI mediated trans-activation in F9 cells, although endogenously present AP1 can influence GPEI in HeLa cells. Co-transfection of delta fosB with c-jun, which forms an inactive c-Jun/delta FosB heterodimer that binds TRE sequences, inhibits GPEI-mediated transcription in AP1-lacking F9 cells as well as AP1-containing HeLa cells. These data suggest novel factor(s) other than AP1 are influencing GPEI. Binding studies reveal multiple nucleoproteins bind to GPEI. These factors are likely responsible for the high level of GPEI-mediated transcription observed in the absence of AP1 and during hepatocarcinogenesis. Images PMID:1408831

The dyad palindromic glutathione transferase P enhancer binds multiple factors including AP1.

PubMed

Diccianni, M B; Imagawa, M; Muramatsu, M

1992-10-11

Glutathione Transferase P (GST-P) gene expression is dominantly regulated by an upstream enhancer (GPEI) consisting of a dyad of palindromically oriented imperfect TPA (12-O-tetradecanoyl-phorbol-13-acetate)-responsive elements (TRE). GPEI is active in AP1-lacking F9 cells as well in AP1-containing HeLa cells. Despite GPEI's similarity to a TRE, c-jun co-transfection has only a minimal effect on transactivation. Antisense c-jun and c-fos co-transfection experiments further demonstrate the lack of a role for AP1 in GPEI mediated trans-activation in F9 cells, although endogenously present AP1 can influence GPEI in HeLa cells. Co-transfection of delta fosB with c-jun, which forms an inactive c-Jun/delta FosB heterodimer that binds TRE sequences, inhibits GPEI-mediated transcription in AP1-lacking F9 cells as well as AP1-containing HeLa cells. These data suggest novel factor(s) other than AP1 are influencing GPEI. Binding studies reveal multiple nucleoproteins bind to GPEI. These factors are likely responsible for the high level of GPEI-mediated transcription observed in the absence of AP1 and during hepatocarcinogenesis.

Association of CYP2E1, GST and mEH genetic polymorphisms with urinary acrylamide metabolites in workers exposed to acrylamide.

PubMed

Huang, Yu-Fang; Chen, Mei-Lien; Liou, Saou-Hsing; Chen, Ming-Feng; Uang, Shi-Nian; Wu, Kuen-Yuh

2011-06-10

This study elucidates the association of acrylamide metabolites, N-acetyl-S-(2-carbamoylethyl)-cysteine (AAMA), N-acetyl-S-(1-carbamoyl-2-hydroxyethyl)-cysteine (GAMA2), and N-acetyl-S-(2-carbamoyl-2-hydroxyethyl)-cysteine (GAMA3) in urine with genetic polymorphisms of the metabolic enzymes cytochrome P450 2E1 (CYP2E1), microsomal epoxide hydrolase (mEH) in exon 3 and exon 4, glutathione transferase theta (GSTT1) and mu (GSTM1), involved in the activation and detoxification of acrylamide (AA) in humans. Eighty-five workers were recruited, including 51 AA-exposed workers and 34 administrative staffs serve as controls. Personal air sampling was performed for the exposed workers. Each subject provided pre- and post-shift urine samples and blood samples. Urinary AAMA, GAMA2 and GAMA3 levels were simultaneously quantified using liquid chromatography-electronspray ionization/tandem mass spectrometry (LC-ESI-MS/MS). CYP2E1, mEH (in exon 3 and exon 4), GSTT1, and GSTM1 were analyzed using polymerase chain reaction (PCR). Our results reveal that AA personal exposures ranged from 4.37 × 10⁻³ to 113.61 μg/m³ with a mean at 15.36 μg/m³. The AAMA, GAMA2, and GAMA3 levels in the exposed group significantly exceeded those in controls. The GAMAs (the sum of GAMA2 and GAMA3)/AAMA ratios, potentially reflecting the proportion of AA metabolized to glycidamide (GA), varied from 0.003 to 0.456, and indicate high inter-individual variability in the metabolism of AA to GA in this study population. Multivariate regression analysis demonstrates that GSTM1 genotypes significantly modify the excretion of urinary AAMA and the GAMAs/AAMA ratio, exon 4 of mEH was significantly associated with the urinary GAMAs levels after adjustment for AA exposures. These results suggest that mEH and/or GSTM1 may be associated with the formation of urinary AAMA and GAMAs. Further study may be needed to shed light on the role of both enzymes in AA metabolism. Copyright © 2011 Elsevier Ireland Ltd. All

Grape pomace extract exerts antioxidant effects through an increase in GCS levels and GST activity in muscle and endothelial cells

PubMed Central

GOUTZOURELAS, NIKOLAOS; STAGOS, DIMITRIOS; HOUSMEKERIDOU, ANASTASIA; KARAPOULIOU, CHRISTINA; KERASIOTI, EFTHALIA; ALIGIANNIS, NEKTARIOS; SKALTSOUNIS, ALEXIOS L; SPANDIDOS, DEMETRIOS A; TSATSAKIS, ARISTIDIS M; KOURETAS, DEMETRIOS

2015-01-01

In a previous study, we demonstrated that a grape pomace extract (GPE) exerted antioxidant activity in endothelial (EA.hy926) and muscle (C2C12) cells through an increase in glutathione (GSH) levels. In the present study, in order to elucidate the mechanisms responsible for the antioxidant activity of GPE, its effects on the expression of critical antioxidant enzymes, such as catalase (CAT), superoxide dismutase (SOD)1, heme oxygenase 1 (HO-1) and gamma-glutamylcysteine synthetase (GCS) were assessed in EA.hy926 and C2C12 cells. Moreover, the effects of GPE on CAT, SOD and glutathione S-transferase (GST) enzymatic activity were evaluated. For this purpose, the C2C12 and EA.hy926 cells were treated with GPE at low and non-cytotoxic concentrations (2.5 and 10 µg/ml for the C2C12 cells; 0.068 and 0.250 µg/ml for the EA.hy926 cells) for 3, 6, 12, 18 and 24 h. Following incubation, enzymatic expression and activity were assessed. The results revealed that treatment with GPE significantly increased GCS levels and GST activity in both the C2C12 and EA.hy926 cells. However, GPE significantly decreased CAT levels and activity, but only in the muscle cells, while it had no effect on CAT levels and activity in the endothelial cells. Moreover, treatment with GPE had no effect on HO-1 and SOD expression and activity in both cell lines. Therefore, the present results provide further evidence of the crucial role of GSH systems in the antioxidant effects exerted by GPE. Thus, GPE may prove to be effective for use as a food supplement for the treatment of oxidative stress-induced pathological conditions of the cardiovascular and skeletal muscle systems, particularly those associated with low GSH levels. PMID:26082074

Association of glutathione S-transferase Ω 1-1 polymorphisms (A140D and E208K) with the expression of interleukin-8 (IL-8), transforming growth factor beta (TGF-β), and apoptotic protease-activating factor 1 (Apaf-1) in humans chronically exposed to arsenic in drinking water.

PubMed

Escobar-García, D M; Del Razo, L M; Sanchez-Peña, L C; Mandeville, P B; Lopez-Campos, C; Escudero-Lourdes, Claudia

2012-06-01

Human exposure to arsenicals is associated with inflammatory-related diseases including different kinds of cancer as well as non-cancerous diseases like neuro-degenerative diseases, atherosclerosis, hypertension, and diabetes. Interindividual susceptibility has been mainly addressed by evaluating the role of genetic polymorphism in metabolic enzymes in inorganic arsenic (iAs) metabolism. Glutathione S-transferase omega 1-1 (GSTO1-1), which had been associated with iAs metabolism, is also known to participate in inflammatory and apoptotic cellular responses. The polymorphism A140D of GSTO1-1 has been not only associated with distinct urinary profile of arsenic metabolites in populations chronically exposed to iAs in drinking water, but also with higher risk of childhood leukemia and lung disease in non-exposed populations, suggesting that GSTO1-1 involvement in other physiologic processes different from toxics metabolism could be more relevant than is thought. We evaluated the association of the presence of A140D and E208K polymorphisms of GSTO1-1 gene with the expression of genes codifying for proteins involved in the inflammatory and apoptotic response in a human population chronically exposed to iAs through drinking water. A140D polymorphism was associated with higher expression of genes codifying for IL-8 and Apaf-1 mainly in heterozygous individuals, while E208K was associated with higher expression of IL-8 and TGF- gene, in both cases, the association was independently of iAs exposure level; however, the exposure to iAs increased slightly but significantly the influence of A140D and E208K polymorphisms on such genes expression. These results suggest an important role of GSTO1-1 in the inflammatory response and the apoptotic process and indicate that A140D and E208K polymorphisms could increase the risk of developing inflammatory and apoptosis-related diseases in As-exposed populations.

Urinary biomarkers in hexachloro-1:3-butadiene-induced acute kidney injury in the female Hanover Wistar rat; correlation of α-glutathione S-transferase, albumin and kidney injury molecule-1 with histopathology and gene expression.

PubMed

Swain, Aubrey; Turton, John; Scudamore, Cheryl L; Pereira, Ines; Viswanathan, Neeti; Smyth, Rosemary; Munday, Michael; McClure, Fiona; Gandhi, Mitul; Sondh, Surjit; York, Malcolm

2011-05-01

Hexachloro-1:3-butadiene (HCBD) causes kidney injury specific to the pars recta of the proximal tubule. In the present studies, injury to the nephron was characterized at 24 h following a single dose of HCBD, using a range of quantitative urinary measurements, renal histopathology and gene expression. Multiplexed renal biomarker measurements were performed using both the Meso Scale Discovery (MSD) and Rules Based Medicine platforms. In a second study, rats were treated with a single nephrotoxic dose of HCBD and the time course release of a range of traditional and newer urinary biomarkers was followed over a 25 day period. Urinary albumin (a marker of both proximal tubular function and glomerular integrity) and α-glutathione S-transferase (α-GST, a proximal tubular cell marker of cytoplasmic leakage) showed the largest fold change at 24 h (day 1) after dosing. Most other markers measured on either the MSD or RBM platforms peaked on day 1 or 2 post-dosing, whereas levels of kidney injury molecule-1 (KIM-1), a marker of tubular regeneration, peaked on day 3/4. Therefore, in rat proximal tubular nephrotoxicity, the measurement of urinary albumin, α-GST and KIM-1 is recommended as they potentially provide useful information about the function, degree of damage and repair of the proximal tubule. Gene expression data provided useful confirmatory information regarding exposure of the kidney and liver to HCBD, and the response of these tissues to HCBD in terms of metabolism, oxidative stress, inflammation, and regeneration and repair. Copyright © 2011 John Wiley & Sons, Ltd.

The glutathione-S-transferase Mu 1 null genotype modulates ozone-induced airway inflammation in humans*

EPA Science Inventory

Background: The Glutathione-S-Transferase Mu 1 null genotype has been reported to be a risk factor for acute respiratory disease associated with increases in ambient air ozone. Ozone is known to cause an immediate decrease in lung function and increased airway inflammation. Howev...

Antioxidant role of glutathione S-transferases: 4-Hydroxynonenal, a key molecule in stress-mediated signaling.

PubMed

Singhal, Sharad S; Singh, Sharda P; Singhal, Preeti; Horne, David; Singhal, Jyotsana; Awasthi, Sanjay

2015-12-15

4-Hydroxy-2-trans-nonenal (4HNE), one of the major end products of lipid peroxidation (LPO), has been shown to induce apoptosis in a variety of cell lines. It appears to modulate signaling processes in more than one way because it has been suggested to have a role in signaling for differentiation and proliferation. It has been known that glutathione S-transferases (GSTs) can reduce lipid hydroperoxides through their Se-independent glutathione-peroxidase activity and that these enzymes can also detoxify LPO end-products such as 4HNE. Available evidence from earlier studies together with results of recent studies in our laboratories strongly suggests that LPO products, particularly hydroperoxides and 4HNE, are involved in the mechanisms of stress-mediated signaling and that it can be modulated by the alpha-class GSTs through the regulation of the intracellular concentrations of 4HNE. We demonstrate that 4HNE induced apoptosis in various cell lines is accompanied with c-Jun-N-terminal kinase (JNK) and caspase-3 activation. Cells exposed to mild, transient heat or oxidative stress acquire the capacity to exclude intracellular 4HNE at a faster rate by inducing GSTA4-4 which conjugates 4HNE to glutathione (GSH), and RLIP76 which mediates the ATP-dependent transport of the GSH-conjugate of 4HNE (GS-HNE). The balance between formation and exclusion promotes different cellular processes - higher concentrations of 4HNE promote apoptosis; whereas, lower concentrations promote proliferation. In this article, we provide a brief summary of the cellular effects of 4HNE, followed by a review of its GST-catalyzed detoxification, with an emphasis on the structural attributes that play an important role in the interactions with alpha-class GSTA4-4. Taken together, 4HNE is a key signaling molecule and that GSTs being determinants of its intracellular concentrations, can regulate stress-mediated signaling, are reviewed in this article. Copyright © 2015 Elsevier Inc. All rights

HMG CoA Lyase (HL): Mutation detection and development of a bacterial expression system for screening the activity of mutant alleles from HL-deficient patients

DOE Office of Scientific and Technical Information (OSTI.GOV)

Robert, M.F.; Ashmarina, L.; Poitier, E.

1994-09-01

HL catalyzes the last step of ketogenesis, and autosomal recessive HL deficiency in humans can cause episodes of hypoglycemia and coma. Structurally, HL is a dimer of identical 325-residue peptides which requires a reducing environment to maintain activity. We cloned the human and mouse HL cDNAs and genes and have performed mutation analysis on cells from 30 HL-deficient probands. Using SSCP and also genomic Southern analysis we have identified putative mutations on 53/60 alleles of these patients (88%). To date, we have found 20 mutations: 3 large deletions, 4 termination mutations, 5 frameshift mutations, and 8 missense mutations which wemore » suspect to be pathogenic based on evolutionary conservation and/or our previous studies on purified HL protein. We have also identified 3 polymorphic variants. In order to directly test the activity of the missense mutations, we established a pGEX-based system, using a glutathione S transferase (GST)-HL fusion protein. Expressed wild-type GST-HL was insoluble. We previously located a reactive Cys at the C-terminus of chicken HL which is conserved in human HL. We produced a mutant HL peptide, C323S, which replaced Cys323 with Ser. Purified C323S is soluble and has similar kinetics to wild-type HL. C323S-containing GST-HL is soluble and enzymatically active. We are cloning and expressing the 8 missense mutations.« less

Stop Sale, Use, or Removal Order: WellPlant, Inc. and GST International, Inc.

EPA Pesticide Factsheets

Stop Sale, Use, or Removal Order (“Order”) issued by the U.S. Environmental Protection Agency Region 9 (EPA) to WelIPlant Inc. and GST International, Inc., concerning all pesticide products bearing the name Mold Manager and any alternate brand names.

GST-PRIME: an algorithm for genome-wide primer design.

PubMed

Leister, Dario; Varotto, Claudio

2007-01-01

The profiling of mRNA expression based on DNA arrays has become a powerful tool to study genome-wide transcription of genes in a number of organisms. GST-PRIME is a software package created to facilitate large-scale primer design for the amplification of probes to be immobilized on arrays for transcriptome analyses, even though it can be also applied in low-throughput approaches. GST-PRIME allows highly efficient, direct amplification of gene-sequence tags (GSTs) from genomic DNA (gDNA), starting from annotated genome or transcript sequences. GST-PRIME provides a customer-friendly platform for automatic primer design, and despite the relative simplicity of the algorithm, experimental tests in the model plant species Arabidopsis thaliana confirmed the reliability of the software. This chapter describes the algorithm used for primer design, its input and output files, and the installation of the standalone package and its use.

S-Glutathionylation of Keap1: a new role for glutathione S-transferase pi in neuronal protection.

PubMed

Carvalho, Andreia Neves; Marques, Carla; Guedes, Rita C; Castro-Caldas, Margarida; Rodrigues, Elsa; van Horssen, Jack; Gama, Maria João

2016-05-01

Oxidative stress is a key pathological feature of Parkinson's disease (PD). Glutathione S-transferase pi (GSTP) is a neuroprotective antioxidant enzyme regulated at the transcriptional level by the antioxidant master regulator nuclear factor-erythroid 2-related factor 2 (Nrf2). Here, we show for the first time that upon MPTP-induced oxidative stress, GSTP potentiates S-glutathionylation of Kelch-like ECH-associated protein 1 (Keap1), an endogenous repressor of Nrf2, in vivo. S-glutathionylation of Keap1 leads to Nrf2 activation and subsequently increases expression of GSTP. This positive feedback regulatory loop represents a novel mechanism by which GSTP elicits antioxidant protection in the brain. © 2016 Federation of European Biochemical Societies.

Drug resistance in epithelial ovarian cancer: P-glycoprotein and glutation S-transferase. Can they play an important role in detecting response to platinum-based chemotherapy as a first-line therapy.

PubMed

Simşek, T; Ozbilim, G; Gülkesen, H; Kaya, H; Sargin, F; Karaveli, S

2001-01-01

Drug resistance is important for the treatment of ovarian cancer. P-glycoprotein and glutation S-transferase as resistance markers play an important role in the effectivity of chemotherapeutical agents. The role of P-glycoprotein and glutation S-transferase in the treatment of epithelial ovarian cancer is not well understood. We investigated the relation between P-glycoprotein and glutation S-transferase level for response to platinum-based chemotherapy in epithelial ovarian cancer. We reviewed 30 cases diagnosed as epithelial ovarian cancer and treated with platinum-based chemotherapy in the Department of Obstetrics and Gynecology, Akdeniz University School of Medicine. The material was attained from initial parafin-embeded blocks stained for P-glycoprotein and glutation S-transferase. The cases that were diagnosed and treated before attending our clinic were not enrolled in the study. Mean age was 58.2 (25-70) and mean gravida 4.1 (0-10). Twenty-four patients (80%) were glutation S-transferase positive. Three cases (10%) out of 30 had positive reaction for P-glycoprotein. No difference was revealed regarding chemotherapy response rate among the cases showing glutation S-transferase positivity and P-glycoprotein negativity. Detection of glutation S-transferase and P-glycoprotein levels in epithelial ovarian cancer tissue is not important for response to platinum-based chemotherapy as a first line.

Role of Metabolic Genes in Blood Aluminum Concentrations of Jamaican Children with and without Autism Spectrum Disorder

PubMed Central

Rahbar, Mohammad H.; Samms-Vaughan, Maureen; Pitcher, Meagan R.; Bressler, Jan; Hessabi, Manouchehr; Loveland, Katherine A.; Christian, MacKinsey A.; Grove, Megan L.; Shakespeare-Pellington, Sydonnie; Beecher, Compton; McLaughlin, Wayne; Boerwinkle, Eric

2016-01-01

Aluminum is a neurotoxic metal with known health effects in animals and humans. Glutathione-S-transferase (GST) genes and enzymes play a major role in detoxification of several heavy metals. Besides a direct relationship with oxidative stress; aluminum decreases GST enzyme activities. Using data from 116 Jamaican children; age 2–8 years; with Autism Spectrum Disorder (ASD) and 116 sex- and age-matched typically developing (TD) children; we investigated the association of polymorphisms in three GST genes (GSTP1; GSTM1; and GSTT1) with mean blood aluminum concentrations in children with and without ASD. Using log-transformed blood aluminum concentration as the dependent variable in a linear regression model; we assessed the additive and interactive effects of ASD status and polymorphisms in the three aforementioned GST genes in relation to blood aluminum concentrations. Although none of the additive effects were statistically significant (all p > 0.16); we observed a marginally significant interaction between GSTP1 Ile105Val (rs1695) and ASD status (p = 0.07); even after controlling for parental education level and consumption of avocado; root vegetables; and tuna (canned fish). Our findings indicate a significantly lower (p < 0.03) adjusted geometric mean blood aluminum concentration for TD children who had the Val/Val genotype (14.57 µg/L); compared with those with Ile/Ile or Ile/Val genotypes who had an adjusted geometric mean of 23.75 µg/L. However; this difference was not statistically significant among the ASD cases (p = 0.76). Our findings indicate that ASD status may be a potential effect modifier when assessing the association between GSTP1 rs1695 and blood aluminum concentrations among Jamaican children. These findings require replication in other populations. PMID:27834815

Cys-X scanning for expansion of active-site residues and modulation of catalytic functions in a glutathione transferase.

PubMed

Norrgård, Malena A; Hellman, Ulf; Mannervik, Bengt

2011-05-13

We propose Cys-X scanning as a semisynthetic approach to engineer the functional properties of recombinant proteins. As in the case of Ala scanning, key residues in the primary structure are identified, and one of them is replaced by Cys via site-directed mutagenesis. The thiol of the residue introduced is subsequently modified by alternative chemical reagents to yield diverse Cys-X mutants of the protein. This chemical approach is orthogonal to Ala or Cys scanning and allows the expansion of the repertoire of amino acid side chains far beyond those present in natural proteins. In its present application, we have introduced Cys-X residues in human glutathione transferase (GST) M2-2, replacing Met-212 in the substrate-binding site. To achieve selectivity of the modifications, the Cys residues in the wild-type enzyme were replaced by Ala. A suite of simple substitutions resulted in a set of homologous Met derivatives ranging from normethionine to S-heptyl-cysteine. The chemical modifications were validated by HPLC and mass spectrometry. The derivatized mutant enzymes were assayed with alternative GST substrates representing diverse chemical reactions: aromatic substitution, epoxide opening, transnitrosylation, and addition to an ortho-quinone. The Cys substitutions had different effects on the alternative substrates and differentially enhanced or suppressed catalytic activities depending on both the Cys-X substitution and the substrate assayed. As a consequence, the enzyme specificity profile could be changed among the alternative substrates. The procedure lends itself to large-scale production of Cys-X modified protein variants.

Association of GSTM1, GSTT1, GSTP1-ILE105VAL and ACE I/D polymorphisms with ankylosing spondylitis.

PubMed

İnal, Esra Erkol; Görükmez, Orhan; Eroğlu, Selma; Görükmez, Özlem; Solak, Özlem; Topak, Ali; Yakut, Tahsin

2016-01-01

Ankylosing spondylitis (AS) is a chronic inflammatory disease of unknown origin. The aim of this study is to clarify the relationships between susceptibility and severity of AS and GST-mu1 (GSTM1), GST-theta1 (GSTT1), GST-pi1 (GSTP1)-Ile105Val and angiotensin-converting enzyme (ACE) I/D polymorphisms in AS patients. One hundred thirty-eight AS patients and seventy-one healthy controls were enrolled in this study. Erythrocyte sedimentation rate and C-reactive protein (CRP) levels of the AS patients were recorded. The scores of the numeric rating scale (NRS) pain, the Bath Ankylosing Spondylitis Activity Index, the Bath Ankylosing Spondylitis Metrology Index and the Bath Ankylosing Spondylitis Functional Index were calculated. The genotypes distributions and allele frequencies of GSTM1, GSTT1, GSTP1-Ile105Val and ACE I/D polymorphisms were compared between patients and healthy controls. The Multiplex polymerase chain reaction (PCR) and the PCR-restriction fragment length polymorphism methods were used to detect the polymorphisms of ACE I/D, the GSTT1 and GSTM1 genes and the GSTP1-Ile105Val polymorphism, respectively. There were significantly higher levels of the GSTT1 null and the ACE II genotypes in AS patients compared to those in healthy controls (p = 0.002 and 0.005, respectively). We found significantly higher levels of CRP and the NRS pain scores in the patients with ACE ID or DD genotypes compared to those in the patients with ACE II genotypes (p = 0.005 and 0.035, respectively). The present results showed that genes involved in protection from oxidative stress and ACE gene may influence disease development and course in AS.

Association of A(313)G glutathione S-transferase P1 germline polymorphism with susceptibility to de novo myelodysplastic syndrome.

PubMed

Zachaki, Sophia; Stavropoulou, Chrysa; Kalomoiraki, Marina; Koromila, Theodora; Daraki, Aggeliki; Manola, Kalliopi N; Mavrou, Ariadni; Kanavakis, Emmanuel; Pantelias, Gabriel E; Sambani, Constantina

2013-08-01

Models for the pathogenesis of myelodysplastic syndrome (MDS) imply the role of individual genetic variations in genes involved in detoxification mechanisms. GSTP1 enzyme plays a key role in the biotransformation of a variety of carcinogens. The corresponding gene is subject to a single nucleotide polymorphism (A(313)G) leading to abolished enzyme activity. In order to evaluate whether the GSTP1 polymorphism influences MDS susceptibility, we conducted a case-control study comprising 310 de novo patients and 370 healthy controls using a real-time polymerase chain reaction (PCR) genotyping method. The GSTP1 gene status was also evaluated in relation to patients' characteristics and chromosomal abnormalities. A significantly higher incidence of the GSTP1 variant genotypes was observed in patients with MDS compared to controls (p < 0.0001). The results revealed increased frequencies of heterozygotes in patients younger than 60 years old and of homozygotes G/G in older patients (p = 0.007). Our results provide evidence for a pathogenetic role of the GSTP1 polymorphism in MDS risk, probably in an age-dependent manner.

Increased N7-methyldeoxyguanosine DNA adducts after occupational exposure to pesticides and influence of genetic polymorphisms of paraoxonase-1 and glutathione S-transferase M1 and T1.

PubMed

Gómez-Martín, Antonio; Altakroni, Bashar; Lozano-Paniagua, David; Margison, Geoffrey P; de Vocht, Frank; Povey, Andrew C; Hernández, Antonio F

2015-06-01

There are concerns about genetic risks associated with long-term exposure to pesticides as these compounds may damage DNA, resulting in mutations that eventually lead to cancer, neurological, and reproductive adverse health effects. This study assessed DNA damage in intensive agricultural workers exposed to pesticides by determining the levels of N7-methyldeoxyguanosine (N7-MedG), an adduct known to be a robust biomarker of recent exposure to chemical methylating agents. A cohort of 39 plastic greenhouse workers was assessed for changes in lymphocyte DNA N7-MedG levels between low level and high level exposures during the course of a spraying season. The contributions of genetic polymorphisms of the pesticide-metabolizing enzymes paraoxonase-1 (PON1) and the glutathione S-transferases, GSTM1 and GSTT1, on N7-MedG levels and other potential confounders were also assessed. N7-MedG increased in the period of high pesticide exposure as compared to the low exposure period (0.23 and 0.18 µmol N7-MedG/mol dG for the unadjusted and adjusted linear mixed models, P = 0.02 and 0.08, respectively). Significant decreased levels of erythrocyte acetylcholinesterase and plasma cholinesterase were observed in the high versus low exposure period in both the unadjusted (2.85 U/g hemoglobin and 213.13 U/L, respectively) and adjusted linear mixed models (2.99 U/g hemoglobin and 230.77 U/L, respectively), indicating pesticide intake. In intensive agriculture workers, higher pesticide exposure increased DNA alkylation levels, further demonstrating the genotoxicity of pesticides in man. In addition, pesticide-exposed individuals with inherited susceptible metabolic genotypes (particularly, null genotype for GSTM1 and the PON1 192R allele) appear to have an increased risk of genotoxic DNA damage. Environ. Mol. Mutagen. 56:437-445, 2015. © 2014 Wiley Periodicals, Inc. © 2014 Wiley Periodicals, Inc.

Susceptibility to breast cancer and three polymorphisms of GSTZ1.

PubMed

Saadat, Iraj; Khalili, Maryam; Nafissi, Samane; Omidvari, Shahpour; Saadat, Mostafa

2012-03-01

Glutathione S-transferases class zeta (GSTζ) is involved in the detoxification of xenobiotic compounds and catalyzes the biotransformation of a variety of α-haloacids including dichloroacetic acid and chlorofluoroacetic acid. It has been reported that, in mice, deficiency of Gstz1 (a member of GSTζ) resulted in the generation of a constant level of oxidative stress. The present study was carried out to investigate the association between genetic polymorphisms of GSTZ1 (in promoter site G-1002A and in coding sites Glu32Lys and Gly42Arg) and risk of breast cancer. We included 106 females with breast cancer and 106 healthy females frequency matched for age. The study polymorphisms were not associated with risk of breast cancer (p>0.05). The polymorphisms of GSTZ1 showed strong linkage disequilibrium among cancer patients and control subjects (p<0.0001). There was no significant difference between cancer patients and controls for frequencies of the GSTZ1 haplotypes (p>0.05). It seems there is no meaningful relationship between the genetic polymorphisms of GSTZ1 and risk of breast cancer.

Molecular chaperones (TrxA, SUMO, Intein, and GST) mediating expression, purification, and antimicrobial activity assays of plectasin in Escherichia coli.

PubMed

Chen, Xin; Shi, Jiawei; Chen, Rui; Wen, Yaoan; Shi, Yu; Zhu, Zhe; Guo, Songwen; Li, Ling

2015-01-01

Plectasin (PS) is the first defensin to be isolated from a fungus, the saprophytic ascomycete Pseudoplectania nigrella, and active against Streptococcus pneumoniae and S. aureus, including antibiotic-resistant pathogens. To establish a bacterium-based production system, we compared the efficiency of four molecular chaperones and corresponding cleavage to the expression and purification of plectasin. The results showed that the yield of plectasin combined with thioredoxin A (TrxA) and small ubiquitin-related modifier (SUMO) was at a higher level (0.0356 and 0.0358 g L(-1), respectively) than that with intein (0.0238 g L(-1)) and glutathione-S-transferase (GST) (0.0243 g L(-1)). TrxA-plectasin, SUMO-plectasin, and 2-plectasin were cleaved at the correct site and purified, but their considerable amount was not cleaved and remained as a fusion peptide. The antimicrobial activity of plectasin cleaved from SUMO--plectasin against methicillin-resistant Staphylococcus aureus (MRSA), penicillin-resistant S. pneumoniae (PRSP), and vancomycin-resistant enterococci (VRE)--was stronger than ampicillin (Amp) for the same amount of substance (P ≤ 0.05). This is the first study to complete and compare the effect of different molecular chaperones and corresponding cleavage with the expression and purification of plectasin in the Escherichia coli expression system, which laid the foundation for future research and may develop the application and production of plectasin. © 2014 International Union of Biochemistry and Molecular Biology, Inc.

Transcriptome and Difference Analysis of Fenpropathrin Resistant Predatory Mite, Neoseiulus barkeri (Hughes)

PubMed Central

Cong, Lin; Chen, Fei; Yu, Shijiang; Ding, Lili; Yang, Juan; Luo, Ren; Tian, Huixia; Li, Hongjun; Liu, Haoqiang; Ran, Chun

2016-01-01

Several fenpropathrin-resistant predatory mites have been reported. However, the molecular mechanism of the resistance remains unknown. In the present study, the Neoseiulus barkeri (N. barkeri) transcriptome was generated using the Illumina sequencing platform, 34,211 unigenes were obtained, and 15,987 were manually annotated. After manual annotation, attentions were attracted to resistance-related genes, such as voltage-gated sodium channel (VGSC), cytochrome P450s (P450s), and glutathione S-transferases (GSTs). A polymorphism analysis detected two point mutations (E1233G and S1282G) in the linker region between VGSC domain II and III. In addition, 43 putative P450 genes and 10 putative GST genes were identified from the transcriptome. Among them, two P450 genes, NbCYP4EV2 and NbCYP4EZ1, and four GST genes, NbGSTd01, NbGSTd02, NbGSTd03 and NbGSTm03, were remarkably overexpressed 3.64–46.69-fold in the fenpropathrin resistant strain compared to that in the susceptible strain. These results suggest that fenpropathrin resistance in N. barkeri is a complex biological process involving many genetic changes and provide new insight into the N. barkeri resistance mechanism. PMID:27240349

A Tau Class Glutathione-S-Transferase is Involved in Trans-Resveratrol Transport Out of Grapevine Cells

PubMed Central

Martínez-Márquez, Ascensión; Martínez-Esteso, María J.; Vilella-Antón, María T.; Sellés-Marchart, Susana; Morante-Carriel, Jaime A.; Hurtado, Elias; Palazon, Javier; Bru-Martínez, Roque

2017-01-01

Vitis vinifera cell cultures respond to pathogens and elicitors by synthesizing and extracellularly accumulating stilbenoid phytoalexins. Large amounts of trans-resveratrol (t-R) are produced when a cell culture is elicited with methylated cyclodextrins (MBCD), either alone or combined with methyl jasmonate (MeJA). t-R transport to the extracellular medium, which represents the apoplastic space, would place this antifungal defense right in the battlefield to efficiently fight against pathogen attack. Yet despite their physiological relevance, these transport pathways are mostly unknown. A broad hypothesis-free DIGE-based proteomic experiment of a temporal series of elicited grapevine cell cultures was performed to explore the expression profiles of t-R biosynthetic proteins and other co-expressing proteins potentially involved in such a cell response. A correlation between two tau class glutathione-S-transferases (GSTs) with several stilbene synthase and phenylalanine ammonia-lyase isoforms, and with the t-R metabolite itself, was found and further assessed by a qRT-PCR gene expression analysis. The best candidate, GSTU-2, was cloned from the cDNA of the MBCD + MeJA-elicited grapevine cells and used for Agrobacterium-mediated grapevine cell transformation. The non-elicited lines that overexpressed GSTU-2 displayed an extracellular t-R accumulating phenotype, but stabilization of t-R required the addition to culture medium of adsorbent compounds, e.g., PVP or β-cyclodextrin. The wild-type cell cultures accumulated no t-R, not even in the presence of adsorbents. The transient expression of the GSTU-2-GFP fusion proteins in grapevine cells showed localisation in the plasma membrane, and the immunoprecipitation of HA-tagged GSTU-2 revealed its interaction with HIR, a plasma membrane-bound protein. These findings are consistent with a functional role in transport. This is the first report providing several pieces of experimental evidence for the involvement of a

Homogentisate solanesyl transferase (HST) cDNA’s in maize

USDA-ARS?s Scientific Manuscript database

Maize white seedling 3 (w3) has served as a model albino-seedling mutant since its discovery in 1923. We show that the w3 phenotype is caused by disruptions in homogentisate solanesyl transferase (HST), an enzyme that catalyzes the committed step in plastoquinone-9 (PQ9) biosynthesis. This reaction ...

Directed evolution of glutathione transferases towards a selective glutathione-binding site and improved oxidative stability.

PubMed

Axarli, Irine; Muleta, Abdi W; Chronopoulou, Evangelia G; Papageorgiou, Anastassios C; Labrou, Nikolaos E

2017-01-01

Glutathione transferases (GSTs) are a family of detoxification enzymes that catalyze the conjugation of glutathione (GSH) to electrophilic compounds. A library of alpha class GSTs was constructed by DNA shuffling using the DNA encoding the human glutathione transferase A1-1 (hGSTA1-1) and the rat glutathione transferase A1-1 (rGSTA1-1). Activity screening of the library allowed the selection of a chimeric enzyme variant (GSTD4) that displayed high affinity towards GSH and GSH-Sepharose affinity adsorbent, higher k cat /K m and improved thermal stability, compared to the parent enzymes. The crystal structures of the GSTD4 enzyme in free form and in complex with GSH were determined to 1.6Šand 2.3Šresolution, respectively. Analysis of the GSTD4 structure showed subtle conformational changes in the GSH-binding site and in electron-sharing network that may contribute to the increased GSH affinity. The shuffled variant GSTD4 was further optimized for improved oxidative stability employing site-saturation mutagenesis. The Cys112Ser mutation confers optimal oxidative stability and kinetic properties in the GSTD4 enzyme. DNA shuffling allowed the creation of a chimeric enzyme variant with improved properties, compared to the parent enzymes. X-ray crystallography shed light on how recombination of a specific segment from homologous GSTA1-1 together with point mutations gives rise to a new functionally competent enzyme with improved binding, catalytic properties and stability. Such an engineered GST would be useful in biotechnology as affinity tool in affinity chromatography as well as a biocatalytic matrix for the construction of biochips or enzyme biosensors. Copyright © 2016 Elsevier B.V. All rights reserved.

Placental biomarkers of PAH exposure and glutathione-S-transferase biotransformation enzymes in an obstetric population from Tijuana, Baja California, Mexico.

PubMed

Dodd-Butera, Teresa; Quintana, Penelope J E; Ramirez-Zetina, Martha; Batista-Castro, Ana C; Sierra, Maria M; Shaputnic, Carolyn; Garcia-Castillo, Maura; Ingmanson, Sonja; Hull, Stacy

2017-01-01

Environmental exposures along the US-Mexico border have the potential to adversely affect the maternal-fetal environment. The purpose of this study was to assess placental biomarkers of environmental exposures in an obstetric population at the California-Baja California border in relation to detoxifying enzymes in the placenta and nutritional status. This study was conducted on consenting, full-term, obstetric patients (n=54), delivering in a hospital in Tijuana, Baja California (BC), Mexico. Placental polyaromatic hydrocarbon (PAH)-DNA adducts were measured in addition to placental glutathione-S-transferase (GST) activity and genotype, maternal serum folate, and maternal and umbilical cord blood lead and cadmium levels. A questionnaire was administered to the mothers to determine maternal occupation in a maquiladora, other exposures, and obstetric indicators. In univariate analysis, maternal serum folate levels were inversely correlated with total PAH-DNA adducts (rho=-0.375, p=0.007); adduct #1 (rho=-0.388, p=0.005); and adduct #3 (rho =-0.430, p=0.002). Maternal lead levels were significantly positively correlated with cord blood lead levels (rho=0.512, p<0.001). Cadmium levels were generally very low but significantly higher in mothers exposed to environmental tobacco smoke (ETS) (either at work or at home, n=10). In multivariate analysis, only maternal serum folate levels remained as a significant negative predictor of total DNA-PAH adducts levels in placenta. These findings affirm that placental tissue is a valuable and readily available source of human tissue for biomonitoring; and indicate that further study of the role of nutrition in detoxification and mitigation of environmental exposures in pregnant women is warranted. Copyright © 2016 Elsevier Inc. All rights reserved.

Regular voluntary exercise cures stress-induced impairment of cognitive function and cell proliferation accompanied by increases in cerebral IGF-1 and GST activity in mice.

PubMed

Nakajima, Sanae; Ohsawa, Ikuroh; Ohta, Shigeo; Ohno, Makoto; Mikami, Toshio

2010-08-25

Chronic stress impairs cognitive function and hippocampal neurogenesis. This impairment is attributed to increases in oxidative stress, which result in the accumulation of lipid peroxide. On the other hand, voluntary exercise enhances cognitive function, hippocampal neurogenesis, and antioxidant capacity in normal animals. However, the effects of voluntary exercise on cognitive function, neurogenesis, and antioxidants in stressed mice are unclear. This study was designed to investigate whether voluntary exercise cures stress-induced impairment of cognitive function accompanied by improvement of hippocampal neurogenesis and increases in antioxidant capacity. Stressed mice were exposed to chronic restraint stress (CRS), which consisted of 12h immobilization daily and feeding in a small cage, for 8 weeks. Exercised mice were allowed free access to a running wheel during their exposure to CRS. At the 6th week, cognitive function was examined using the Morris water maze (MWM) test. Daily voluntary exercise restored stress-induced impairment of cognitive function and the hippocampal cell proliferation of newborn cells but not cell survival. Voluntary exercise increased insulin-like growth factor 1 (IGF-1) protein and mRNA expression in the cerebral cortex and liver, respectively. In addition, CRS resulted in a significant increase in the number of 4-hydrosynonenal (4-HNE)-positive cells in the hippocampal dentate gyrus; whereas, voluntary exercise inhibited it and enhanced glutathione s-transferases (GST) activity in the brain. These findings suggest that voluntary exercise attenuated the stress-induced impairment of cognitive function accompanied by improvement of cell proliferation in the dentate gyrus. This exercise-induced improvement was attributed to exercise-induced enhancement of IGF-1 protein and GST activity in the brain. Copyright 2010 Elsevier B.V. All rights reserved.

The insect repellent DEET (N,N-diethyl-3-methylbenzamide) increases the synthesis of glutathione S-transferase in cultured mosquito cells.

PubMed

Hellestad, Vanessa J; Witthuhn, Bruce A; Fallon, Ann M

2011-04-01

DEET (N,N-diethyl-3-methylbenzamide) is the active ingredient used in many commonly used insect repellents, but its mode of action remains poorly understood. Efforts to identify properties that could lead to the development of more effective active ingredients have distinguished among DEET's repellent, deterrent, and insecticidal activities. We used an Aedes albopictus mosquito cell line to evaluate DEET's toxicological properties in the absence of sensory input mediated by the olfactory system. When cells were treated with DEET and labeled with [(35)S]methionine/cysteine, a single 25-kDa protein was induced, relative to other proteins, on SDS-polyacrylamide gels. The 25-kDa band from DEET-treated cells was enriched in peptides corresponding to glutathione S-transferase D10 and/or theta in the Aedes aegypti genome. Consistent with the increased expression of the labeled protein, DEET-treated cells had increased glutathione S-transferase activity, and the radiolabeled band bound to Sepharose 4B containing reduced glutathione. By analyzing partial tryptic digests, we established that DEET induces the homolog of A. aegypti glutathione S-transferase, class theta, corresponding to protein XP_001658009.1 in the NCBI database. This specific effect of DEET at the subcellular level suggests that DEET induces physiological responses that extend beyond recognition by the peripheral olfactory system.

Expression of a Drosophila glutathione transferase in Arabidopsis confers the ability to detoxify the environmental pollutant, and explosive, 2,4,6-trinitrotoluene.

PubMed

Tzafestas, Kyriakos; Razalan, Maria M; Gyulev, Ivan; Mazari, Aslam M A; Mannervik, Bengt; Rylott, Elizabeth L; Bruce, Neil C

2017-04-01

The explosive 2,4,6-trinitrotoluene (TNT) is a significant, global environmental pollutant that is both toxic and recalcitrant to degradation. Given the sheer scale and inaccessible nature of contaminated areas, phytoremediation may be a viable clean-up approach. Here, we have characterized a Drosophila melanogaster glutathione transferase (DmGSTE6) which has activity towards TNT. Recombinantly expressed, purified DmGSTE6 produces predominantly 2-glutathionyl-4,6-dinitrotoluene, and has a 2.5-fold higher Maximal Velocity (V max ), and five-fold lower Michaelis Constant (K m ) than previously characterized TNT-active Arabidopsis thaliana (Arabidopsis) GSTs. Expression of DmGSTE6 in Arabidopsis conferred enhanced resistance to TNT, and increased the ability to remove TNT from contaminated soil relative to wild-type plants. Arabidopsis lines overexpressing TNT-active GSTs AtGST-U24 and AtGST-U25 were compromised in biomass production when grown in the absence of TNT. This yield drag was not observed in the DmGSTE6-expressing Arabidopsis lines. We hypothesize that increased levels of endogenous TNT-active GSTs catalyse excessive glutathionylation of endogenous substrates, depleting glutathione pools, an activity that DmGST may lack. In conclusion, DmGSTE6 has activity towards TNT, producing a compound with potential for further biodegradation. Selecting or manipulating plants to confer DmGSTE6-like activity could contribute towards development of phytoremediation strategies to clean up TNT from polluted military sites. © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.

Serum vitamin C and other biomarkers differ by genotype of phase 2 enzyme genes GSTM1 and GSTT1123

PubMed Central

Shaikh, Nishat; Jensen, Christopher D; Volberg, Vitaly; Holland, Nina

2011-01-01

Background: Glutathione S-transferases (GSTs) detoxify environmental chemicals and are involved in oxidative stress pathways. Deletion polymorphisms affect enzyme activities and have been associated with risk of disease. Objective: The objective was to clarify whether biomarkers of oxidation, antioxidation, inflammation, and nutritional factors differ by GST genotype in healthy adults. Design: Subjects (n = 383) consisted of nonsmokers and nonusers of antiinflammatory drugs and antioxidant vitamin supplements. Deletion polymorphisms of GSTM1 and GSTT1 were genotyped. F2-isoprostanes, malondialdehyde, C-reactive protein, serum vitamin C, carotenoids, tocopherols, and other nutritional factors were assessed. Results: The concentration of serum vitamin C was higher in persons with the inactive GSTM1-0 genotype (P = 0.006). This relation was unchanged after adjustment for age, sex, BMI, or dietary vitamin C. F2-isoprostanes and malondialdehyde were lower in the GSTM1-0 and GSTT1-0 groups, respectively, but significance was lost after control for serum vitamin C. The dual deletion, GSTM1-0/GSTT1-0 (n = 37), was associated with higher serum iron and total and LDL-cholesterol concentrations (all P < 0.01) and lower malondialdehyde concentrations, which persisted after adjustment for age, sex, BMI, and serum vitamin C. Carotenoids and α- and γ-tocopherols were not associated with either genotype. Conclusions: Oxidative stress and inflammation biomarkers differ by GST genotype, but serum vitamin C appears to be the most consistent factor. Examination of other relevant genes may be needed to understand the concentration and function of ascorbic acid in the GST enzyme system. This trial is registered at clinicaltrials.gov as NCT00079963. PMID:21813807

Differential transcription of cytochrome P450s and glutathione S transferases in DDT-susceptible and resistant Drosophila melanogaster strains in response to DDT and oxidative stress

USDA-ARS?s Scientific Manuscript database

Metabolic DDT resistance in Drosophila melanogaster has previously been associated with constitutive over-transcription of cytochrome P450s. Increased P450 activity has also been associated with increased oxidative stress. In contrast, over-transcription of glutathione S transferases (GSTs) has been...

Overexpression of a glutathione S-transferase (Mdgst) and a galactosyltransferase-like gene (Mdgt1) is responsible for imidacloprid resistance in house flies.

PubMed

Reid, William R; Sun, Haina; Becnel, James J; Clark, Andrew G; Scott, Jeffrey G

2018-06-21

Neonicotinoids are the largest class of insecticides and are used for control of house fly populations at animal production facilities throughout the world. There have been several reports of neonicotinoid resistance in house fly populations, but identification of the factors involved in resistance has proven challenging. The KS8S3 population of house flies is highly resistant to the neonicotinoid insecticide imidacloprid due to two factors: one on chromosome 3 and one on chromosome 4. A comparative transcriptomic approach was used, followed by validation using transgenic Drosophila melanogaster to investigate the genes responsible for resistance in the KS8S3 strain. Overexpression of a microsomal glutathione S-transferase (Mdgst) was identified as the factor likely responsible for resistance on chromosome 3. Resistance on chromosome 4 appears to be due to an unidentified trans-regulatory gene which causes overexpression of a galactosyltransferase-like gene (Mdgt1). No single nucleotide polymorphisms were found that could be associated with imidacloprid resistance. Identification of the underlying processes that cause imidacloprid resistance is an important first step towards the development of novel and sensitive resistance monitoring techniques. It will be valuable to investigate if overexpression of Mdgst and Mdgt1 are found in other imidacloprid resistant populations. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

GSTO and AS3MT genetic polymorphisms and differences in urinary arsenic concentrations among residents in Bangladesh.

PubMed

Rodrigues, Ema G; Kile, Molly; Hoffman, Elaine; Quamruzzaman, Quazi; Rahman, Mahmuder; Mahiuddin, Golam; Hsueh, Yumei; Christiani, David C

2012-05-01

We determined whether single nucleotide polymorphisms (SNPs) in the glutathione S-transferase omega (GSTO) and arsenic(III)methyltransferase (AS3MT) genes were associated with concentrations of urinary arsenic metabolites among 900 individuals without skin lesions in Bangladesh. Four SNPs were assessed in these genes. A pathway analysis evaluated the association between urinary arsenic metabolites and SNPs. GSTO1 rs4925 homozygous wild type was significantly associated with higher monomethylarsonic acid (MMA) and dimethylarsinic acid urinary concentrations, whereas wild-type AS3MT rs11191439 had significantly lower levels of As(III) and MMA. Genetic polymorphisms GSTO and As3MT modify arsenic metabolism as evidenced by altered urinary arsenic excretion.

Employment of colorimetric enzyme assay for monitoring expression and solubility of GST fusion proteins targeted to inclusion bodies.

PubMed

Mačinković, Igor S; Abughren, Mohamed; Mrkic, Ivan; Grozdanović, Milica M; Prodanović, Radivoje; Gavrović-Jankulović, Marija

2013-12-01

High levels of recombinant protein expression can lead to the formation of insoluble inclusion bodies. These complex aggregates are commonly solubilized in strong denaturants, such as 6-8M urea, although, if possible, solubilization under milder conditions could facilitate subsequent refolding and purification of bioactive proteins. Commercially available GST-tag assays are designed for quantitative measurement of GST activity under native conditions. GST fusion proteins accumulated in inclusion bodies are considered to be undetectable by such assays. In this work, solubilization of recombinantly produced proteins was performed in 4M urea. The activity of rGST was assayed in 2M urea and it was shown that rGST preserves 85% of its activity under such denaturing conditions. A colorimetric GST activity assay with 1-chloro-2, 4-dinitrobenzene (CDNB) was examined for use in rapid detection of expression targeted to inclusion bodies and for the identification of inclusion body proteins which can be solubilized in low concentrations of chaotropic agents. Applicability of the assay was evaluated by tracking protein expression of two GST-fused allergens of biopharmaceutical value in E. coli, GST-Der p 2 and GST-Mus a 5, both targeted to inclusion bodies. Copyright © 2013 Elsevier B.V. All rights reserved.

Epidermal growth factor regulation of glutathione S-transferase gene expression in the rat is mediated by class Pi glutathione S-transferase enhancer I.

PubMed

Matsumoto, M; Imagawa, M; Aoki, Y

2000-07-01

Using chloramphenicol acetyltransferase assays we showed that epidermal growth factor (EGF), transforming growth factor alpha (TGF alpha), and 3,3',4,4',5-pentachlorobiphenyl (PenCB) induce class Pi glutathione S-transferase (GSTP1) in primary cultured rat liver parenchymal cells. GSTP1 enhancer I (GPEI), which is required for the stimulation of GSTP1 expression by PenCB, also mediates EGF and TGF alpha stimulation of GSTP1 gene expression. However, hepatocyte growth factor and insulin did not stimulate GPEI-mediated gene expression. On the other hand, the antioxidant reagents butylhydroxyanisole and t-butylhydroquinone, stimulated GPEI-mediated gene expression, but the level of GSTP1 mRNA was not elevated. Our observations suggest that EGF and TGF alpha induce GSTP1 by the same signal transduction pathway as PenCB. Since the sequence of GPEI is similar to that of the antioxidant responsive element (ARE), some factors which bind to ARE might play a role in GPEI-mediated gene expression.

Epidermal growth factor regulation of glutathione S-transferase gene expression in the rat is mediated by class Pi glutathione S-transferase enhancer I.

PubMed Central

Matsumoto, M; Imagawa, M; Aoki, Y

2000-01-01

Using chloramphenicol acetyltransferase assays we showed that epidermal growth factor (EGF), transforming growth factor alpha (TGF alpha), and 3,3',4,4',5-pentachlorobiphenyl (PenCB) induce class Pi glutathione S-transferase (GSTP1) in primary cultured rat liver parenchymal cells. GSTP1 enhancer I (GPEI), which is required for the stimulation of GSTP1 expression by PenCB, also mediates EGF and TGF alpha stimulation of GSTP1 gene expression. However, hepatocyte growth factor and insulin did not stimulate GPEI-mediated gene expression. On the other hand, the antioxidant reagents butylhydroxyanisole and t-butylhydroquinone, stimulated GPEI-mediated gene expression, but the level of GSTP1 mRNA was not elevated. Our observations suggest that EGF and TGF alpha induce GSTP1 by the same signal transduction pathway as PenCB. Since the sequence of GPEI is similar to that of the antioxidant responsive element (ARE), some factors which bind to ARE might play a role in GPEI-mediated gene expression. PMID:10861232

The synthesis of ethacrynic acid thiazole derivatives as glutathione S-transferase pi inhibitors.

PubMed

Li, Ting; Liu, Guyue; Li, Hongcai; Yang, Xinmei; Jing, Yongkui; Zhao, Guisen

2012-04-01

Glutathione S-transferase pi (GSTpi) is a phase II enzyme which protects cells from death and detoxifies chemotherapeutic agents in cancer cells. Ethacrynic acid (EA) is a weak GSTpi inhibitor. Structure modifications were done to improve the ability of EA to inhibit GSTpi activity. Eighteen EA thiazole derivatives were designed and synthesized. Compounds 9a, 9b and 9c with a replacement of carboxyl group of EA by a heterocyclic thiazole exhibited improvement over EA to inhibit GSTpi activity. Copyright © 2012 Elsevier Ltd. All rights reserved.