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.

The glutathione-S-transferase mu 1 (GSTM1) null genotype and increased neutrophil response to low-level ozone (0.06 ppm).

EPA Science Inventory

Background: Exposure of healthy young adults to 03 modulates immune cell biology in the airways and causes a significant increase in neutrophilic inflammation which can vary considerably in magnitude across individuals. The GSTM1null genotype modulates Oj-induced inflammation, bu...

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

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.

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...

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.

Interactions of GST Polymorphisms in Air Pollution Exposure and Respiratory Diseases and Allergies.

PubMed

Bowatte, Gayan; Lodge, Caroline J; Perret, Jennifer L; Matheson, Melanie C; Dharmage, Shyamali C

2016-11-01

The purpose of this review is to summarize the evidence from recently published original studies investigating how glutathione S-transferase (GST) gene polymorphisms modify the impact of air pollution on asthma, allergic diseases, and lung function. Current studies in epidemiological and controlled human experiments found evidence to suggest that GSTs modify the impact of air pollution exposure on respiratory diseases and allergies. Of the nine articles included in this review, all except one identified at least one significant interaction with at least one of glutathione S-transferase pi 1 (GSTP1), glutathione S-transferase mu 1 (GSTM1), or glutathione S-transferase theta 1 (GSTT1) genes and air pollution exposure. The findings of these studies, however, are markedly different. This difference can be partially explained by regional variation in the exposure levels and oxidative potential of different pollutants and by other interactions involving a number of unaccounted environment exposures and multiple genes. Although there is evidence of an interaction between GST genes and air pollution exposure for the risk of respiratory disease and allergies, results are not concordant. Further investigations are needed to explore the reasons behind the discordancy.

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.

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

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.

Protective role of Scoparia dulcis plant extract on brain antioxidant status and lipidperoxidation in STZ diabetic male Wistar rats

PubMed Central

Pari, Leelavinothan; Latha, Muniappan

2004-01-01

Background The aim of the study was to investigate the effect of aqueous extract of Scoparia dulcis on the occurrence of oxidative stress in the brain of rats during diabetes by measuring the extent of oxidative damage as well as the status of the antioxidant defense system. Methods Aqueous extract of Scoparia dulcis plant was administered orally (200 mg/kg body weight) and the effect of extract on blood glucose, plasma insulin and the levels of thiobarbituric acid reactive substances (TBARS), hydroperoxides, superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione-S-transferase (GST) and reduced glutathione (GSH) were estimated in streptozotocin (STZ) induced diabetic rats. Glibenclamide was used as standard reference drug. Results A significant increase in the activities of plasma insulin, superoxide dismutase, catalase, glutathione peroxidase, glutathione-S-transferase and reduced glutathione was observed in brain on treatment with 200 mg/kg body weight of Scoparia dulcis plant extract (SPEt) and glibenclamide for 6 weeks. Both the treated groups showed significant decrease in TBARS and hydroperoxides formation in brain, suggesting its role in protection against lipidperoxidation induced membrane damage. Conclusions Since the study of induction of the antioxidant enzymes is considered to be a reliable marker for evaluating the antiperoxidative efficacy of the medicinal plant, these findings suggest a possible antiperoxidative role for Scoparia dulcis plant extract. Hence, in addition to antidiabetic effect, Scoparia dulcis possess antioxidant potential that may be used for therapeutic purposes. PMID:15522116

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 that GSTM1 null genotype leads to an increased oxidative stress compared with wild genotype. PMID:28584578

Redox Protein Expression Predicts Radiotherapeutic Response in Early-Stage Invasive Breast Cancer Patients

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

Woolston, Caroline M.; Al-Attar, Ahmad; Storr, Sarah J.

2011-04-01

Purpose: Early-stage invasive breast cancer patients have commonly undergone breast-conserving surgery and radiotherapy. In a large majority of these patients, the treatment is effective; however, a proportion will develop local recurrence. Deregulated redox systems provide cancer cells protection from increased oxidative stress, such as that induced by ionizing radiation. Therefore, the expression of redox proteins was examined in tumor specimens from this defined cohort to determine whether such expression could predict response. Methods and Materials: The nuclear and cytoplasmic expression of nine redox proteins (glutathione, glutathione reductase, glutaredoxin, glutathione peroxidase 1, 3, and 4, and glutathione S-transferase-{theta}, -{pi}, and -{alpha})more » was assessed using conventional immunohistochemistry on a tissue microarray of 224 tumors. Results: A high cytoplasmic expression of glutathione S-transferase-{theta} significantly correlated with a greater risk of local recurrence (p = .008) and, when combined with a low nuclear expression (p = .009), became an independent predictive factor (p = .002) for local recurrence. High cytoplasmic expression of glutathione S-transferase-{theta} also correlated with a worse overall survival (p = .009). Low nuclear and cytoplasmic expression of glutathione peroxidase 3 (p = .002) correlated with a greater risk of local recurrence and was an independent predictive factor (p = .005). These proteins did not correlate with tumor grade, suggesting their function might be specific to the regulation of oxidative stress rather than alterations of tumor phenotype. Only nuclear (p = .005) and cytoplasmic (p = .001) expression of glutathione peroxidase 4 correlated with the tumor grade. Conclusions: Our results support the use of redox protein expression, namely glutathione S-transferase-{theta} and glutathione peroxidase 3, to predict the response to radiotherapy in early-stage breast cancer patients. If incorporated into routine diagnostic tests, they have the potential to aid clinicians in their stratification of patients into more tailored treatment regimens. Future targeted therapies to these systems might improve the efficacy of reactive oxygen species-inducing therapies, such as radiotherapy.« less

Does maternal exposure to artificial food coloring additives increase oxidative stress in the skin of rats?

PubMed

Başak, K; Başak, P Y; Doğuç, D K; Aylak, F; Oğuztüzün, S; Bozer, B M; Gültekin, F

2017-10-01

Glutathione-S-transferase (GST) and cytochrome P450 family 1 subfamily A polypeptide 1 (CYP1A1) metabolize and detoxify carcinogens, drugs, environmental pollutants, and reactive oxygen species. Changes of GST expression in tissues and gene mutations have been reported in association with many neoplastic skin diseases and dermatoses. Widely used artificial food coloring additives (AFCAs) also reported to effect primarily behavioral and cognitive function and cause neoplastic diseases and several inflammatory skin diseases. We aimed to identify the changes in expression of GSTs, CYP1A1, and vascular endothelial growth factor (VEGF) in rat skin which were maternally exposed AFCAs. A rat model was designed to evaluate the effects of maternal exposure of AFCAs on skin in rats. "No observable adverse effect levels" of commonly used AFCAs as a mixture were given to female rats before and during gestation. Immunohistochemical expression of GSTs, CYP1A1, and VEGF was evaluated in their offspring. CYP1A1, glutathione S-transferase pi (GSTP), glutathione S-transferase alpha (GSTA), glutathione S-transferase mu (GSTM), glutathione S-transferase theta (GSTT), and VEGF were expressed by epidermal keratinocytes, dermal fibroblasts, sebaceous glands, hair follicle, and subcutaneous striated muscle in the normal skin. CYP1A1, GSTA, and GSTT were expressed at all microanatomical sites of skin in varying degrees. The expressions of CYP1A1, GSTA, GSTT, and VEGF were decreased significantly, while GSTM expression on sebaceous gland and hair follicle was increased. Maternal exposure of AFCAs apparently effects expression of the CYP1A1, GSTs, and VEGF in the skin. This prominent change of expressions might play role in neoplastic and nonneoplastic skin diseases.

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

Novosphingobium aromaticivorans uses a Nu-class glutathione S-transferase as a glutathione lyase in breaking the β-aryl ether bond of lignin

PubMed Central

Kontur, Wayne S.; Bingman, Craig A.; Olmsted, Charles N.; Wassarman, Douglas R.; Ulbrich, Arne; Gall, Daniel L.; Smith, Robert W.; Yusko, Larissa M.; Fox, Brian G.; Noguera, Daniel R.; Coon, Joshua J.; Donohue, Timothy J.

2018-01-01

As a major component of plant cell walls, lignin is a potential renewable source of valuable chemicals. Several sphingomonad bacteria have been identified that can break the β-aryl ether bond connecting most phenylpropanoid units of the lignin heteropolymer. Here, we tested three sphingomonads predicted to be capable of breaking the β-aryl ether bond of the dimeric aromatic compound guaiacylglycerol-β-guaiacyl ether (GGE) and found that Novosphingobium aromaticivorans metabolizes GGE at one of the fastest rates thus far reported. After the ether bond of racemic GGE is broken by replacement with a thioether bond involving glutathione, the glutathione moiety must be removed from the resulting two stereoisomers of the phenylpropanoid conjugate β-glutathionyl-γ-hydroxypropiovanillone (GS-HPV). We found that the Nu-class glutathione S-transferase NaGSTNu is the only enzyme needed to remove glutathione from both (R)- and (S)-GS-HPV in N. aromaticivorans. We solved the crystal structure of NaGSTNu and used molecular modeling to propose a mechanism for the glutathione lyase (deglutathionylation) reaction in which an enzyme-stabilized glutathione thiolate attacks the thioether bond of GS-HPV, and the reaction proceeds through an enzyme-stabilized enolate intermediate. Three residues implicated in the proposed mechanism (Thr51, Tyr166, and Tyr224) were found to be critical for the lyase reaction. We also found that Nu-class GSTs from Sphingobium sp. SYK-6 (which can also break the β-aryl ether bond) and Escherichia coli (which cannot break the β-aryl ether bond) can also cleave (R)- and (S)-GS-HPV, suggesting that glutathione lyase activity may be common throughout this widespread but largely uncharacterized class of glutathione S-transferases. PMID:29449375

Multidrug Resistance-Associated Protein 1 (MRP1) mediated vincristine resistance: effects of N-acetylcysteine and Buthionine Sulfoximine

PubMed Central

Akan, Ilhan; Akan, Selma; Akca, Hakan; Savas, Burhan; Ozben, Tomris

2005-01-01

Background Multidrug resistance mediated by the multidrug resistance-associated protein 1 (MRP1) decreases cellular drug accumulation. The exact mechanism of MRP1 involved multidrug resistance has not been clarified yet, though glutathione (GSH) is likely to have a role for the resistance to occur. N-acetylcysteine (NAC) is a pro-glutathione drug. DL-Buthionine (S,R)-sulfoximine (BSO) is an inhibitor of GSH synthesis. The aim of our study was to investigate the effect of NAC and BSO on MRP1-mediated vincristine resistance in Human Embryonic Kidney (HEK293) and its MRP1 transfected 293MRP cells. Human Embryonic Kidney (HEK293) cells were transfected with a plasmid encoding whole MRP1 gene. Both cells were incubated with vincristine in the presence or absence of NAC and/or BSO. The viability of both cells was determined under different incubation conditions. GSH, Glutathione S-Transferase (GST) and glutathione peroxidase (GPx) levels were measured in the cell extracts obtained from both cells incubated with different drugs. Results N-acetylcysteine increased the resistance of both cells against vincristine and BSO decreased NAC-enhanced MRP1-mediated vincristine resistance, indicating that induction of MRP1-mediated vincristine resistance depends on GSH. Vincristine decreased cellular GSH concentration and increased GPx activity. Glutathione S-Transferase activity was decreased by NAC. Conclusion Our results demonstrate that NAC and BSO have opposite effects in MRP1 mediated vincristine resistance and BSO seems a promising chemotherapy improving agent in MRP1 overexpressing tumor cells. PMID:16042792

Spectrofluorimetric assay method for glutathione and glutathione transferase using monobromobimane.

PubMed

Yakubu, S I; Yakasai, I A; Musa, A

2011-06-01

The primary role of glutathione transferase is to defend an organism from toxicities through catalyzing the reaction of glutathione (GSH) with potentially toxic compounds or metabolites to their chemically and biologically inert conjugates. The objective of the study was to develop a simple and sensitive spectrofluorimetric assay method for glutathione transferase using monobromobimane (MBB), a non fluorescent compound with electrophilic site. MBB slowly reacted with glutathione to form fluorescent glutathione conjugate and that the reaction was catalysed by glutathione transferase. Both non-enzymatic and enzymatic reaction products of MBB, in presence of GSH in phosphate buffer (pH 6.5), were measured by following increase of fluorescence at wavelength of 475nm. For validation of the assay method, the kinetic parameters such as the apparent Michaelis-Mente constants and maximum rates of conjugate formation as well as the specific activity of rat hepatic glutathione transferase were determined. The method was found to be sensitive, thus, applied to measure glutathione contents of crude preparation of rat hepatic cytosol fraction.

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.

Structure-activity relationships of 4-hydroxyalkenals in the conjugation catalysed by mammalian glutathione transferases.

PubMed Central

Danielson, U H; Esterbauer, H; Mannervik, B

1987-01-01

The substrate specificities of 15 cytosolic glutathione transferases from rat, mouse and man have been explored by use of a homologous series of 4-hydroxyalkenals, extending from 4-hydroxypentenal to 4-hydroxypentadecenal. Rat glutathione transferase 8-8 is exceptionally active with the whole range of 4-hydroxyalkenals, from C5 to C15. Rat transferase 1-1, although more than 10-fold less efficient than transferase 8-8, is the second most active transferase with the longest chain length substrates. Other enzyme forms showing high activities with these substrates are rat transferase 4-4 and human transferase mu. The specificity constants, kcat./Km, for the various enzymes have been determined with the 4-hydroxyalkenals. From these constants the incremental Gibbs free energy of binding to the enzyme has been calculated for the homologous substrates. The enzymes responded differently to changes in the length of the hydrocarbon side chain and could be divided into three groups. All glutathione transferases displayed increased binding energy in response to increased hydrophobicity of the substrate. For some of the enzymes, steric limitations of the active site appear to counteract the increase in binding strength afforded by increased chain length of the substrate. Comparison of the activities with 4-hydroxyalkenals and other activated alkenes provides information about the active-site properties of certain glutathione transferases. The results show that the ensemble of glutathione transferases in a given species may serve an important physiological role in the conjugation of the whole range of 4-hydroxyalkenals. In view of its high catalytic efficiency with all the homologues, rat glutathione transferase 8-8 appears to have evolved specifically to serve in the detoxication of these reactive compounds of oxidative metabolism. PMID:3426557

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.

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

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

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.

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.

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

Use of organic amendments as a bioremediation strategy to reduce the bioavailability of chlorpyrifos insecticide in soils. Effects on soil biology.

PubMed

Tejada, Manuel; Gómez, Isidoro; Del Toro, Marina

2011-10-01

The sorption capacity of both an organic municipal solid waste by-product (MSW) and a cow manure (CM) in a soil polluted with chlorpyrifos, as well as its effect on soil microbial activity, and weight, reproductive parameters and glutathione-S-transferase activity of two earthworm species (Eisenia fetida and Lumbricus terrestris) were studied. Chlorpyrifos was added at the recommended application rate (5 L ha(-1); 768 mg chlorpyrifos kg(-1)) and treated with MSW at a rate of 10% and CM at a rate of 5.8% in order to apply the same amount of organic matter to the soil. An unamended polluted soil was used as control. Earthworm cocoon number, average weight of cocoon, and number of juveniles per cocoon were measured after 30 days of incubation, whereas soil enzymatic activities, earthworm weight, and glutathione-S-transferase activity of earthworms were measured after 3, 45 and 90 days. Soil enzymatic activities, reproductive and glutathione-S-transferase activity in both worms decreased in polluted soil. The inhibition percentage of soil enzymatic activities, reproductive and glutathione-S-transferase activity in both worms was lower in MSW-amended soil than for CM-amended soil. The toxic effect of chlorpyrifos on E. fetida was lowest compared to L. terrestris. This suggested that the addition of organic wastes with higher humic than fulvic acid concentration is more beneficial for remediation of soils polluted with chlorpyrifos. Copyright © 2011 Elsevier Inc. All rights reserved.

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

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

The 30 kDa protein co-purified with chick liver glutathione S-transferases is a carbonyl reductase.

PubMed

Tsai, S P; Wang, L Y; Yeh, H I; Tam, M F

1996-02-08

An unidentified 30 kDa protein was co-purified with chick liver glutathione S-transferases from S-hexylglutathione affinity column. The protein was isolated to apparent homogeneity with chromatofocusing. The molecular mass of the protein was determined to be 30 277 +/- 3 dalton by mass spectrometry. The protein was digested with Achromobacter proteinase I. Amino-acid sequence analyses of the resulting peptides show a high degree of identity with those of human carbonyl reductase. The protein is active with menadione as substrate. Thus, it is identified as chick liver carbonyl reductase.

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.

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

METABOLISM OF 1,1- AND 1,3- DICHLOROPROPENE: A MECHANISM OF BIOACTIVATION BY GLUTATHIONE

EPA Science Inventory

Glutathione transferases (GST) catalyze the reaction of glutathione (GSH) with haloalkenes via a nucleophilic vinylic substitution mechanism (SNV reaction). The source water contaminants 1,1-dichloropropene and 1,3-dichloropropene, which are under scrutiny by the U.S.EPA, were...

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

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

Hybrid molecule from O2-(2,4-dinitrophenyl)diazeniumdiolate and oleanolic acid: a glutathione S-transferase π-activated nitric oxide prodrug with selective anti-human hepatocellular carcinoma activity and improved stability.

PubMed

Fu, Junjie; Liu, Ling; Huang, Zhangjian; Lai, Yisheng; Ji, Hui; Peng, Sixun; Tian, Jide; Zhang, Yihua

2013-06-13

A series of hybrids from O(2)-(2,4-dinitrophenyl)diazeniumdiolate and oleanolic acid (OA) were designed, synthesized, and biologically evaluated as novel nitric oxide (NO)-releasing prodrugs that could be activated by glutathione S-transferase π (GSTπ) overexpressed in a number of cancer cells. It was discovered that the most active compound, 21, released high levels of NO selectively in HCC cells but not in the normal cells and exhibited potent antiproliferative activity in vitro as well as remarkable tumor-retarding effects in vivo. Compared with the reported GSTπ-activated prodrugs JS-K and PABA/NO, 21 exhibited remarkably improved stability in the absence of GSTπ. Importantly, the decomposition of 21 occurred in the presence of GSTπ and was much more effective than in glutathione S-transferase α. Additionally, 21 induced apoptosis in HepG2 cells by arresting the cell cycle at the G2/M phase, activating both the mitochondrion-mediated pathway and the MAPK pathway and enhancing the intracellular production of ROS.

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

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.

Spirulina improves antioxidant status by reducing oxidative stress in rabbits fed a high-cholesterol diet.

PubMed

Kim, Mi Yeon; Cheong, Sun Hee; Lee, Jeung Hee; Kim, Min Ji; Sok, Dai-Eun; Kim, Mee Ree

2010-04-01

The beneficial effect of Spirulina (Spirulina platensis) on tissue lipid peroxidation and oxidative DNA damage was tested in the hypercholesterolemic New Zealand White rabbit model. After hypercholesterolemia was induced by feeding a high cholesterol (0.5%) diet (HCD) for 4 weeks, then HCD supplemented with 1% or 5% Spirulina (SP1 or SP5, respectively) was provided for an additional 8 weeks. Spirulina supplementation significantly reduced the increased lipid peroxidation level in HCD-fed rabbits, and levels recovered to control values. Oxidative stress biomarkers such as glutathione, glutathione peroxidase, glutathione reductase, and glutathione S-transferase were significantly improved in the liver and red blood cells of rabbits fed SP1. Furthermore, SP5 induced antioxidant enzyme activity by 3.1-fold for glutathione, 2.5-fold for glutathione peroxidase, 2.7-fold for glutathione reductase, and 2.3-fold for glutathione S-transferase in liver, compared to the HCD group. DNA damage in lymphocytes was significantly reduced in both the SP1 and SP5 groups, based on the comet assay. Findings from the present study suggest that dietary supplementation with Spirulina may be useful to protect the cells from lipid peroxidation and oxidative DNA damage.

Developing Breast Cancer Program at Xavier; Genomic and Proteomic Analysis of Signaling Pathways Involved in Xenohormone and MEK5 Regulation of Breast Cancer

DTIC Science & Technology

2009-05-01

that upregulations of Vimentin (VIM), Heat shock 70 kDa protein 4 (HSPA4), Glutathione S-transferase P ( GSTP1 ), and Creatine kinase B-type (CKB), and...MEK5 versus MCF-7-VEC cells, vimentin (VIM), glutathione-S-transferase P ( GSTP1 ), and creatine kinase B-type (CKB) were upregulated, and keratin 8...with distinct proteomic changes (upregulation of VIM/vim, GSTP1 / gstp1 , and CKB/ckb; and downregulation of KRT8/krt8, KRT19/krt19, and GSTM3/gstm3). We

Developing Breast Cancer Program at Xavier; Genomic and Proteomic Analysis of Signaling Pathways Involved in Xenohormone and MEK5 Regulation of Breast Cancer

DTIC Science & Technology

2010-05-01

Heat shock 70 kDa protein 4 (HSPA4), Glutathione S-transferase P ( GSTP1 ), and Creatine kinase B-type (CKB), and downregulations of Keratin 8 (KRT8...VIM), glutathione-S-transferase P ( GSTP1 ), and creatine kinase B-type (CKB) were upregulated, and keratin 8 (KRT8), keratin 19 (KRT19) and...upregulation of VIM/vim, GSTP1 / gstp1 , and CKB/ckb; and downregulation of KRT8/krt8, KRT19/krt19, and GSTM3/gstm3). We further demonstrate that MEK5

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

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

Chlorpyrifos-induced biochemical changes in Cyprinus carpio: Ameliorative effect of curcumin.

PubMed

Yonar, M Enis

2018-04-30

The aim of this study was to determine protective effects of curcumin on some haematological values and oxidant/antioxidant status in Cyprinus carpio exposed to chlorpyrifos. The fish were exposed to two sublethal concentrations of chlorpyrifos (0.040 and 0.080mgL), and curcumin (100mg per kg of fish weight) was simultaneously administered for 14 days. Blood and tissue (liver, kidney, and gill) samples were collected at the end of the experiment and analysed to determine the haematological profile (red blood cell count, white blood cell count, haemoglobin concentration, and haematocrit level) and oxidant/antioxidant status (malondialdehyde level and superoxide dismutase, catalase, glutathione peroxidase, and glutathione-S-transferase activities) of the fish. There was a significant decrease in the red blood cell count, the haemoglobin concentration, and the haematocrit level and a increase in the white blood cell count of CPF-treated fish. The results revealed a significant increase in the malondialdehyde levels of the groups that were exposed to CPF. Conversely, the MDA levels were significantly decreased by curcumin. Also, CPF exposure caused a significant increase in the superoxide dismutase and glutathione-S-transferase activities and a significant decrease in the catalase and glutathione peroxidase activities. However, curcumin reversed the superoxide dismutase, catalase, glutathione peroxidase, and glutathione-S-transferase activities. In conclusion, this study demonstrated that CPF had a negative effect on the haematological values and the oxidant/antioxidant status of the fish. The simultaneous administration of curcumin was neutralised CPF-induced toxicity. Copyright © 2017 Elsevier Inc. All rights reserved.

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

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 had a decreased GSH K{sub m} value, whereas little impact on maleylpyruvate kinetics was observed, suggesting that this residue plays an important role in GSH binding. An evolutionary trend in this residue appears to have developed not only in prokaryotic and eukaryotic GSTZs, but also among the wider class of cGSTs.« less

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.

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)

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.

Biological definition of multiple chemical sensitivity from redox state and cytokine profiling and not from polymorphisms of xenobiotic-metabolizing enzymes

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

De Luca, Chiara; Scordo, Maria G.; Cesareo, Eleonora

Background: Multiple chemical sensitivity (MCS) is a poorly clinically and biologically defined environment-associated syndrome. Although dysfunctions of phase I/phase II metabolizing enzymes and redox imbalance have been hypothesized, corresponding genetic and metabolic parameters in MCS have not been systematically examined. Objectives: We sought for genetic, immunological, and metabolic markers in MCS. Methods: We genotyped patients with diagnosis of MCS, suspected MCS and Italian healthy controls for allelic variants of cytochrome P450 isoforms (CYP2C9, CYP2C19, CYP2D6, and CYP3A5), UDP-glucuronosyl transferase (UGT1A1), and glutathione S-transferases (GSTP1, GSTM1, and GSTT1). Erythrocyte membrane fatty acids, antioxidant (catalase, superoxide dismutase (SOD)) and glutathione metabolizing (GST,more » glutathione peroxidase (Gpx)) enzymes, whole blood chemiluminescence, total antioxidant capacity, levels of nitrites/nitrates, glutathione, HNE-protein adducts, and a wide spectrum of cytokines in the plasma were determined. Results: Allele and genotype frequencies of CYPs, UGT, GSTM, GSTT, and GSTP were similar in the Italian MCS patients and in the control populations. The activities of erythrocyte catalase and GST were lower, whereas Gpx was higher than normal. Both reduced and oxidised glutathione were decreased, whereas nitrites/nitrates were increased in the MCS groups. The MCS fatty acid profile was shifted to saturated compartment and IFNgamma, IL-8, IL-10, MCP-1, PDGFbb, and VEGF were increased. Conclusions: Altered redox and cytokine patterns suggest inhibition of expression/activity of metabolizing and antioxidant enzymes in MCS. Metabolic parameters indicating accelerated lipid oxidation, increased nitric oxide production and glutathione depletion in combination with increased plasma inflammatory cytokines should be considered in biological definition and diagnosis of MCS.« less

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.

Biomarkers as a tool to assess effects of chromium (VI): comparison of responses in zebrafish early life stages and adults.

PubMed

Domingues, Inês; Oliveira, Rhaul; Lourenço, Joana; Grisolia, Cesar Koppe; Mendo, Sónia; Soares, A M V M

2010-09-01

The present work aims to compare the sensitivity of embryos and adult zebrafish to chromium (VI) (as potassium dichromate) focusing on biomarkers (cholinesterase, glutathione S-transferase and lactate dehydrogenase) as endpoints. Zebrafish eggs showed less sensitivity to Cr (VI) (96 h-LC50=145.7 mg/L) than adults (96 h-LC50=39.4 mg/L) probably due to the protective action of the chorion. However, biomarkers were much more responsive in larvae than in adults and gave clear indications about Cr (VI) mode of action: it seems to be neurotoxic (inhibited cholinesterase), to inhibit glutathione S-transferase activity and to interfere with cellular metabolic activity (changes in lactate dehydrogenase activity) in larvae. In adults, only glutathione S-transferase was responsive, showing a clear inhibition. The responsiveness of the analyzed biomarkers in larvae reinforces the idea of the usefulness of early life stage assays in the assessment of chemicals effects. Moreover, early life stage assays also contributed with relevant information regarding anomalies in larvae development and behavior. Further research should focus on the use of biomarkers to assess long term effects which are ecologically more relevant. Copyright (c) 2010 Elsevier Inc. All rights reserved.

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.

Gene Polymorphisms of Glutathione S-Transferase T1/M1 in Egyptian Children and Adolescents with Type 1 Diabetes Mellitus.

PubMed

Barseem, Naglaa; Elsamalehy, Mona

2017-06-01

Oxidative stress plays an important role in the pathogenesis of type 1 diabetes mellitus (T1DM). To evaluate the association of glutathione S-transferase mu 1 (GST M1) and glutathione S-transferase theta 1 (GST T1) polymorphisms with development of T1DM and disease-related risk factors. Measurement of fasting glucose, serum creatinine, lipid profile, and glycosylated hemoglobin (HbA1c), as well as evaluation of GST T1 and M1 genetic polymorphisms using polymerase chain reaction were done in 64 diabetic children and 41 controls. The diabetic group had significantly higher fasting glucose, HbA1c, and cholesterol levels. GST T1 null genotype was more frequent in the diabetic than the control group with 4.2-fold increased risk of T1DM (odds ratio=4.2; 95% confidence interval=1.6-11.5; p=0.03). Significant positive associations were found with lipid profile, HbA1c, and duration of illness but not with age, age at onset, and body mass index. Gene polymorphisms of the enzyme GST are associated with development of T1DM and disease-related risk factors.

1-3-A Resolution Structure of Human Glutathione S-Transferase With S-Hexyl Glutathione Bound Reveals Possible Extended Ligandin Binding Site

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

Trong, I.Le; Stenkamp, R.E.; Ibarra, C.

2005-08-22

Cytosolic glutathione S-transferases (GSTs) play a critical role in xenobiotic binding and metabolism, as well as in modulation of oxidative stress. Here, the high-resolution X-ray crystal structures of homodimeric human GSTA1-1 in the apo form and in complex with S-hexyl glutathione (two data sets) are reported at 1.8, 1.5, and 1.3A respectively. At this level of resolution, distinct conformations of the alkyl chain of S-hexyl glutathione are observed, reflecting the nonspecific nature of the hydrophobic substrate binding site (H-site). Also, an extensive network of ordered water, including 75 discrete solvent molecules, traverses the open subunit-subunit interface and connects the glutathionemore » binding sites in each subunit. In the highest-resolution structure, three glycerol moieties lie within this network and directly connect the amino termini of the glutathione molecules. A search for ligand binding sites with the docking program Molecular Operating Environment identified the ordered water network binding site, lined mainly with hydrophobic residues, suggesting an extended ligand binding surface for nonsubstrate ligands, the so-called ligandin site. Finally, detailed comparison of the structures reported here with previously published X-ray structures reveal a possible reaction coordinate for ligand-dependent conformational changes in the active site and the C-terminus.« less

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

Impact of haloperidol and quetiapine on the expression of genes encoding antioxidant enzymes in human neuroblastoma SH-SY5Y cells.

PubMed

Schmidt, Andreas Johannes; Hemmeter, Ulrich Michael; Krieg, Jürgen-Christian; Vedder, Helmut; Heiser, Philip

2009-05-01

Antipsychotics are known to alter antioxidant activities in vivo. Therefore, the aim of the present study was to examine in the human neuroblastoma SH-SY5Y cell line the impact of a typical (haloperidol) and an atypical (quetiapine) antipsychotic on the expression of genes encoding the key enzymes of the antioxidant metabolism (Cu, Zn superoxide dismutase; Mn superoxide dismutase; glutathione peroxidase; catalase) and enzymes of the glutathione metabolism (gamma-glutamyl cysteine synthetase, glutathione-S-transferase, gamma-glutamyltranspeptidase, glutathione reductase). The cells were incubated for 24h with 0.3, 3, 30 and 300microM haloperidol and quetiapine, respectively; mRNA levels were measured by polymerase chain reaction. In the present study, we observed mostly significant decreases of mRNA contents. With respect to the key pathways, we detected mainly effects on the mRNA levels of the hydrogen peroxide detoxifying enzymes. Among the enzymes of the glutathione metabolism, glutathione-S-transferase- and gamma-glutamyltranspeptidase-mRNA levels showed the most prominent effects. Taken together, our results demonstrate a significantly reduced expression of genes encoding for antioxidant enzymes after treatment with the antipsychotics, haloperidol and quetiapine.

Hepatoprotective effect of chrysin on prooxidant-antioxidant status during ethanol-induced toxicity in female albino rats.

PubMed

Sathiavelu, Jayanthi; Senapathy, Giftson Jebakkan; Devaraj, Rajkumar; Namasivayam, Nalini

2009-06-01

To evaluate the effect of chrysin, a natural, biologically active compound extracted from many plants, honey and propolis, on the tissue and circulatory antioxidant status, and lipid peroxidation in ethanol-induced hepatotoxicity in rats. Rats were divided into four groups. Groups 1 and 2 received isocaloric glucose. Groups 3 and 4 received 20% ethanol, equivalent to 5 g/kg bodyweight every day. Groups 2 and 4 received chrysin (20 mg/kg bodyweight) dissolved in 0.5% dimethylsulfoxide. The results showed significantly elevated levels of tissue and circulatory thiobarbituric acid reactive substances, conjugated dienes and lipid hydroperoxides, and significantly lowered enzymic and non-enzymic antioxidant activity of superoxide dismutase, catalase and glutathione-related enzymes such as glutathione peroxidase, glutathione reductase, glutathione-S-transferase, reduced glutathione, vitamin C and vitamin E in ethanol-treated rats compared with the control. Chrysin administration to rats with ethanol-induced liver injury significantly decreased the levels of thiobarbituric acid reactive substances, lipid hydroperoxides and conjugated dienes, and significantly elevated the activity of superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, glutathione-S-transferase and the levels of reduced glutathione, vitamin C and vitamin E in the tissues and circulation compared with those of the unsupplemented ethanol-treated rats. The histological changes observed in the liver and kidney correlated with the biochemical findings. Chrysin offers protection against free radical-mediated oxidative stress in rats with ethanol-induced liver injury.

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

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 in limiting Cd availability in the food chain. PMID:21283689

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 Tyr 8 facilitates the ionization of the thiol group of glutathione bound to glutathione S-transferase, but is not required for enzyme activity. PMID:8762135

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

Dual pharmacological inhibition of glutathione and thioredoxin systems synergizes to kill colorectal carcinoma stem cells.

PubMed

Tanaka, Genki; Inoue, Ken-Ichi; Shimizu, Takayuki; Akimoto, Kazumi; Kubota, Keiichi

2016-09-01

NRF2 stabilizes redox potential through genes for glutathione and thioredoxin antioxidant systems. Whether blockade of glutathione and thioredoxin is useful in eliminating cancer stem cells remain unknown. We used xenografts derived from colorectal carcinoma patients to investigate the pharmacological inhibition of glutathione and thioredoxin systems. Higher expression of five glutathione S-transferase isoforms (GSTA1, A2, M4, O2, and P1) was observed in xenograft-derived spheroids than in fibroblasts. Piperlongumine (2.5-10 μmol/L) and auranofin (0.25-4 μmol/L) were used to inhibit glutathione S-transferase π and thioredoxin reductase, respectively. Piperlongumine or auranofin alone up-regulated the expression of NRF2 target genes, but not TP53 targets. While piperlongumine showed modest cancer-specific cell killing (IC50 difference between cancer spheroids and fibroblasts: P = 0.052), auranofin appeared more toxic to fibroblasts (IC50 difference between cancer spheroids and fibroblasts: P = 0.002). The synergism of dual inhibition was evaluated by determining the Combination Index, based on the number of surviving cells with combination treatments. Molar ratios indicated synergism in cancer spheroids, but not in fibroblasts: (auranofin:piperlongumine) = 2:5, 1:5, 1:10, and 1:20. Cancer-specific cell killing was achieved at the following drug concentrations (auranofin:piperlongumine): 0.25:2.5 μmol/L, 0.5:2.5 μmol/L, or 0.25:5 μmol/L. The dual inhibition successfully decreased CD44v9 surface presentation and delayed tumor emergence in nude mouse. However, a small subpopulation persistently survived and accumulated phosphorylated histone H2A. Such "persisters" still retained lesser but significant tumorigenicity. Thus, dual inhibition of glutathione S-transferase π and thioredoxin reductase could be a feasible option for decreasing the tumor mass and CD44v9-positive fraction by disrupting redox regulation. © 2016 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.

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.

Transmutation of human glutathione transferase A2-2 with peroxidase activity into an efficient steroid isomerase.

PubMed

Pettersson, Par L; Johansson, Ann-Sofie; Mannervik, Bengt

2002-08-16

A major goal in protein engineering is the tailor-making of enzymes for specified chemical reactions. Successful attempts have frequently been based on directed molecular evolution involving libraries of random mutants in which variants with desired properties were identified. For the engineering of enzymes with novel functions, it would be of great value if the necessary changes of the active site could be predicted and implemented. Such attempts based on the comparison of similar structures with different substrate selectivities have previously met with limited success. However, the present work shows that the knowledge-based redesign restricted to substrate-binding residues in human glutathione transferase A2-2 can introduce high steroid double-bond isomerase activity into the enzyme originally characterized by glutathione peroxidase activity. Both the catalytic center activity (k(cat)) and catalytic efficiency (k(cat)/K(m)) match the values of the naturally evolved glutathione transferase A3-3, the most active steroid isomerase known in human tissues. The substrate selectivity of the mutated glutathione transferase was changed 7000-fold by five point mutations. This example demonstrates the functional plasticity of the glutathione transferase scaffold as well as the potential of rational active-site directed mutagenesis as a complement to DNA shuffling and other stochastic methods for the redesign of proteins with novel functions.

Bisubstrate Kinetics of Glutathione S-Transferase: A Colorimetric Experiment for the Introductory Biochemistry Laboratory

ERIC Educational Resources Information Center

Stefanidis, Lazaros; Scinto, Krystal V.; Strada, Monica I.; Alper, Benjamin J.

2018-01-01

Most biochemical transformations involve more than one substrate. Bisubstrate enzymes catalyze multiple chemical reactions in living systems and include members of the transferase, oxidoreductase, and ligase enzyme classes. Working knowledge of bisubstrate enzyme kinetic models is thus of clear importance to the practicing biochemist. However,…

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.

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.

Effects of selected metal oxide nanoparticles on Artemia salina larvae: evaluation of mortality and behavioural and biochemical responses.

PubMed

Gambardella, Chiara; Mesarič, Tina; Milivojević, Tamara; Sepčić, Kristina; Gallus, Lorenzo; Carbone, Serena; Ferrando, Sara; Faimali, Marco

2014-07-01

The aim was to investigate the toxicity of selected metal oxide nanoparticles (MO-NPs) on the brine shrimp Artemia salina, by evaluating mortality and behavioural and biochemical responses. Larvae were exposed to tin(IV) oxide (stannic oxide (SnO2)), cerium(IV) oxide (CeO2) and iron(II, III) oxide (Fe3O4) NPs for 48 h in seawater, with MO-NP suspensions from 0.01 to 1.0 mg/mL. Mortality and behavioural responses (swimming speed alteration) and enzymatic activities of cholinesterase, glutathione-S-transferase and catalase were evaluated. Although the MO-NPs did not induce any mortality of the larvae, they caused changes in behavioural and biochemical responses. Swimming speed significantly decreased in larvae exposed to CeO2 NPs. Cholinesterase and glutathione-S-transferase activities were significantly inhibited in larvae exposed to SnO2 NPs, whereas cholinesterase activity significantly increased after CeO2 NP and Fe3O4 NP exposure. Catalase activity significantly increased in larvae exposed to Fe3O4 NPs. In conclusion, swimming alteration and cholinesterase activity represent valid endpoints for MO-NP exposure, while glutathione-S-transferase and catalase activities appear to be NP-specific.

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.

Effects of Moderate Alcohol Consumption on Gene Expression Related to Colonic Inflammation and Antioxidant Enzymes in Rats

PubMed Central

Klarich, DawnKylee S.; Penprase, Jerrold; Cintora, Patricia; Medrano, Octavio; Erwin, Danielle; Brasser, Susan M.; Hong, Mee Young

2017-01-01

Excessive alcohol consumption is a risk factor associated with colorectal cancer; however, some studies have reported that moderate alcohol consumption may not contribute additional risk for developing colorectal cancer while others suggest that moderate alcohol consumption provides a protective effect that reduces colorectal cancer risk. The purpose of this study was to determine the effects of moderate voluntary alcohol (20% ethanol) intake on alternate days for 3 months in outbred Wistar rats on risk factors associated with colorectal cancer development. Colonic gene expression of cyclooxygenase-2, RelA, 8-oxoguanine DNA glycosylase 1, superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, glutathione-S-transferase M1, and aldehyde dehydrogenase 2 were determined. Blood alcohol content, liver function enzyme activities, and 8-oxo-deoxyguanosine DNA adducts were also assessed. Alcohol-treated rats were found to have significantly lower 8-oxo-deoxyguanosine levels in blood, a marker of DNA damage. Alanine aminotransferase and lactate dehydrogenase were both significantly lower in the alcohol group. Moderate alcohol significantly decreased cyclooxygenase-2 gene expression, an inflammatory marker associated with colorectal cancer risk. The alcohol group had significantly increased glutathione-S-transferase M1 expression, an antioxidant enzyme that helps detoxify carcinogens, such as acetaldehyde, and significantly increased aldehyde dehydrogenase 2 expression, which allows for greater acetaldehyde clearance. Increased expression of glutathione-S-transferase M1 and aldehyde dehydrogenase 2 likely contributed to reduce mucosal damage that is caused by acetaldehyde accumulation. These results indicate that moderate alcohol may reduce the risk for colorectal cancer development, which was evidenced by reduced inflammation activity and lower DNA damage after alcohol exposure. PMID:28599714

Acute toxicity and sublethal effects of gallic and pelargonic acids on the zebrafish Danio rerio.

PubMed

Techer, Didier; Milla, Sylvain; Fontaine, Pascal; Viot, Sandrine; Thomas, Marielle

2015-04-01

Gallic and pelargonic acids are naturally found in a variety of plants and food products. Despite their extensive use in man-made applications, little is known regarding their potential risks to aquatic vertebrates. The aim of this work was to assess the acute toxicity of these polyphenolic and fatty acid compounds to the zebrafish. In order to get insights into sublethal effects, the enzyme activity of usual biomarkers related to oxidative stress and biotransformation were also assessed in fish. These latter included total superoxide dismutase, catalase as well as total glutathione peroxidase for antioxidant defence mechanisms and glutathione S-transferase for biotransformation related enzyme. Gallic acid was practically non-toxic (96-h lethal concentration (LC50) > 100 mg/L) whereas pelargonic acid was slightly toxic (96-h LC50 of 81.2 mg/L). Moreover, biomarker analyses indicated enhanced superoxide dismutase activity in fish exposed to 20, 40 and 100 mg/L of gallic acid compared to control. A dose-dependent induction of glutathione peroxidase and glutathione S-transferase was reported following gallic acid exposure at the tested concentrations of 10, 20 and 40 mg/L, with the exception of 100 mg/L of substance where basal activity levels were reported. In the case of pelargonic acid, there was no change in antioxidant enzyme activity while an inhibition of glutathione S-transferase was observed from organisms exposed to 45, 58 and 76 mg/L of test solution. The results concerning sublethal effects on biological parameters of zebrafish highlighted thereby the need for further investigations following chronic exposure to both organic acids.

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.

Antioxidant protection mechanism of chick hepatic mitochondria exposed to lanthanum chloride & neodymium chloride treatment.

PubMed

Ghosh, N; Chattopadhyay, D; Chatterjee, G C

1991-05-01

Acute lanthanum chloride (250 mg/kg body wt) and neodymium chloride (200 mg/kg body wt) administrations resulted in significant enhancement of glutathione level in chick hepatic mitochondria. However, glutathione-s-transferase activity was depressed. There was no alteration in the activity of glutathione reductase. Activity of glucose-6-phosphate dehydrogenase was not altered under lanthanum and neodymium treatment. There was a significant enhancement of intramitochondrial glutathione peroxidase and superoxide dismutase. Lipid peroxidation remains the same as control group of animals.

Preferential glutathione conjugation of a reverse diol epoxide compared to a bay region diol epoxide of phenanthrene in human hepatocytes: relevance to molecular epidemiology studies of glutathione-s-transferase polymorphisms and cancer.

PubMed

Hecht, Stephen S; Berg, Jeannette Zinggeler; Hochalter, J Bradley

2009-03-16

Bay region diol epoxides are recognized ultimate carcinogens of polycyclic aromatic hydrocarbons (PAH), and in vitro studies have demonstrated that they can be detoxified by conjugation with glutathione, leading to the widely investigated hypothesis that individuals with low activity forms of glutathione-S-transferases are at higher risk of PAH induced cancer, a hypothesis that has found at most weak support in molecular epidemiology studies. A weakness in this hypothesis was that the mercapturic acids resulting from the conjugation of PAH bay region diol epoxides had never been identified in human urine. We recently analyzed smokers' urine for mercapturic acids derived from phenanthrene, the simplest PAH with a bay region. The only phenanthrene diol epoxide-derived mercapturic acid in smokers' urine was produced from the reverse diol epoxide, anti-phenanthrene-3,4-diol-1,2-epoxide (11), not the bay region diol epoxide, anti-phenanthrene-1,2-diol-3,4-epoxide (10), which does not support the hypothesis noted above. In this study, we extended these results by examining the conjugation of phenanthrene metabolites with glutathione in human hepatocytes. We identified the mercapturic acid N-acetyl-S-(r-4,t-2,3-trihydroxy-1,2,3,4-tetrahydro-c-1-phenanthryl)-L-cysteine (14a), (0.33-35.9 pmol/mL at 10 microM 8, 24 h incubation, N = 10) in all incubations with phenanthrene-3,4-diol (8) and the corresponding diol epoxide 11, but no mercapturic acids were detected in incubations with phenanthrene-1,2-diol (7), and only trace amounts were observed in incubations with the corresponding bay region diol epoxide 10. Taken together with our previous results, these studies clearly demonstrate that glutathione conjugation of a reverse diol epoxide of phenanthrene is favored over conjugation of a bay region diol epoxide. Since reverse diol epoxides of PAH are generally weakly or nonmutagenic/carcinogenic, these results, if generalizable to other PAH, do not support the widely held assumption that glutathione-S-transferases are important in the detoxification of PAH in humans.

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

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.

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 Protein-Protein Interactions with Glutathione-S-Transferase (GST) Fusion Proteins.

PubMed

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

2007-08-01

INTRODUCTIONGlutathione-S-transferase (GST) fusion proteins 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. This article describes the use of GST fusion proteins as probes for the identification of protein-protein interactions.

The biochemical adaptations of spotted wing drosophila (Diptera: Drosophilidae) to fresh fruits reduced fructose concentrations and glutathione-S transferase activities

USDA-ARS?s Scientific Manuscript database

Spotted wing drosophila (SWD), Drosophila suzukii, is an invasive and economically damaging pest in Europe and North America, because the females have a serrated ovipositor enabling them to infest ripening almost all small fruits before harvest. Also flies are strongly attracted to fresh fruits rath...

Amitriptyline may have a supportive role in cancer treatment by inhibiting glutathione S-transferase pi (GST-π) and alpha (GST-α).

PubMed

Kulaksiz-Erkmen, Gulnihal; Dalmizrak, Ozlem; Dincsoy-Tuna, Gamze; Dogan, Arın; Ogus, I Hamdi; Ozer, Nazmi

2013-02-01

A tricyclic anti-depressant, amitriptyline, is a highly prescribed drug for cancer patients for mood elevation but there are limited studies about the interaction of amitriptyline with glutathione S-transferases pi (GST-π) and glutathione S-transferases alpha (GST-α). GST isozymes have been implicated in chemotherapeutic drug resistance. We demonstrated that the concentration dependent inhibition of GST-π and GST-α by amitriptyline followed inverse hyperbolic inhibition curves with IC(50) values of 5.54 and 8.32 mM, respectively. When the varied substrate was GSH, amitriptyline inhibited both isozymes competitively and similar K(i) values were found for GST-π (K(i) = 1.61 ± 0.17 mM) and GST-α (K(i) = 1.45 ± 0.20 mM). On the other hand, when the varied substrate was CDNB, the inhibition types were non-competitive for GST-π (K(i) = 1.98 ± 0.31 mM) and competitive for GST-α (K(i) = 1.57 ± 0.16 mM). Amitriptyline, in addition to its antidepressant effect, might also have a minor supportive role on the effectiveness of the anticancer drugs by decreasing their elimination through inhibiting GST-π and GST-α.

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

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.

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.

Differences in response of glucuronide and glutathione conjugating enzymes to aflatoxin B/sub 1/ and N-acetylaminofluorene in underfed rats

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

Rajpurohit, R.; Krishnaswamy, K.

Changes in the hepatic drug/xenobiotic-metabolizing enzymes in underfed rats exposed to aflatoxin B/sub 1/ and N-acetylaminofluorene were investigated. Neither carcinogen, fed at the level of 10 ..mu..g and 0.667 mg per 100 g body weight, respectively, over a period of 3 wk, had any significant influence on cytochrome P-450 and aryl hydrocarbon hydroxylase in the undernourished rats. Significantly low activities of UDP-glucuronyltransferase and glutathione S-transferase were observed in food-restricted animals fed on aflatoxin B/sub 1/. N-acetylaminofluorene, on the other hand stimulated both the enzyme activities in the underfed group, to as much observed in the respective well-fed treated group. UDP-Glucuronyltransferasemore » and glutathione S-transferase in undernutrition seem to respond differently to aflatoxin B/sub 1/ and N-acetylaminofluorene. Further studies are needed to assess the possible consequences of such alterations.« less

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

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 different specificities for flavonoid ligands. In addition, our data provide evidence to suggest that GST-mediate flavonoid transport is glutathione-dependent. PMID:27536314

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

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

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.

Anticancer activity of Cynodon dactylon L. root extract against diethyl nitrosamine induced hepatic carcinoma

PubMed Central

Kowsalya, R.; Kaliaperumal, Jagatheesh; Vaishnavi, M.; Namasivayam, Elangovan

2015-01-01

Background: Hepatocellular carcinoma is one of the most common cancers and a lethal disease. In view of the limited treatment and a grave prognosis of liver cancer, preventive control has been emphasized. Materials and Methods: The methanolic extract of roots of Cynodon dactylon was screened for its hepato-protective activity in diethyl nitrosamine (DEN) induced liver cancer in Swiss albino mice. The plant extract at a dose of 50 mg/kg was administered orally once a week, up to 30 days after DEN administration. The animals were sacrificed; blood sample and liver tissue were collected and used for enzyme assay such as, asparatate amino transferase (AST), alanine aminotransferase (ALT), catalase (CAT), glutathione peroxidase (GPx) and glutathione-S-transferase (GST). The liver marker enzymes AST and ALT produced significant results in the protective action. Results: The antioxidant enzyme assay results concerning the improved activity of GPx, GST and CAT. These results concluded that enhanced levels of antioxidant enzyme and reduced amount of serum amino transaminase, which are suggested to be the major mechanisms of C. dactylon root extract in protecting the mice from hepatocarcinoma induced by DEN. These biochemical observations were supplemented by histopathological examination of liver sections. Conclusion: The methanolic extract of C. dactylon possesses significant anticancer properties PMID:25992348

Caribbean yellow band disease compromises the activity of catalase and glutathione S-transferase in the reef-building coral Orbicella faveolata exposed to anthracene.

PubMed

Montilla, Luis Miguel; Ramos, Ruth; García, Elia; Cróquer, Aldo

2016-05-03

Healthy and diseased corals are threatened by different anthropogenic sources, such as pollution, a problem expected to become more severe in the near future. Despite the fact that coastal pollution and coral diseases might represent a serious threat to coral reef health, there is a paucity of controlled experiments showing whether the response of diseased and healthy corals to xenobiotics differs. In this study, we exposed healthy and Caribbean yellow band disease (CYBD)-affected Orbicella faveolata colonies to 3 sublethal concentrations of anthracene to test if enzymatic responses to this hydrocarbon were compromised in CYBD-affected tissues. For this, a 2-factorial fully orthogonal design was used in a controlled laboratory bioassay, using tissue condition (2 levels: apparently healthy and diseased) and pollutant concentration (4 levels: experimental control, 10, 30 and 100 ppb concentration) as fixed factors. A permutation-based ANOVA (PERMANOVA) was used to test the effects of condition and concentration on the specific activity of 3 enzymatic biomarkers: catalase, glutathione S-transferase, and glutathione peroxidase. We found a significant interaction between the concentration of anthracene and the colony condition for catalase (Pseudo-F = 3.84, df = 3, p < 0.05) and glutathione S-transferase (Pseudo-F = 3.29, df = 3, p < 0.05). Moreover, our results indicated that the enzymatic response to anthracene in CYBD-affected tissues was compromised, as the activity of these enzymes decreased 3- to 4-fold compared to healthy tissues. These results suggest that under a potential scenario of increasing hydrocarbon coastal pollution, colonies of O. faveolata affected with CYBD might become more vulnerable to the deleterious effects of chemical pollution.

AtMRP1 gene of Arabidopsis encodes a glutathione S-conjugate pump: isolation and functional definition of a plant ATP-binding cassette transporter gene.

PubMed

Lu, Y P; Li, Z S; Rea, P A

1997-07-22

Because plants produce cytotoxic compounds to which they, themselves, are susceptible and are exposed to exogenous toxins (microbial products, allelochemicals, and agrochemicals), cell survival is contingent on mechanisms for detoxifying these agents. One detoxification mechanism is the glutathione S-transferase-catalyzed glutathionation of the toxin, or an activated derivative, and transport of the conjugate out of the cytosol. We show here that a transporter responsible for the removal of glutathione S-conjugates from the cytosol, a specific Mg2+-ATPase, is encoded by the AtMRP1 gene of Arabidopsis thaliana. The sequence of AtMRP1 and the transport capabilities of membranes prepared from yeast cells transformed with plasmid-borne AtMRP1 demonstrate that this gene encodes an ATP-binding cassette transporter competent in the transport of glutathione S-conjugates of xenobiotics and endogenous substances, including herbicides and anthocyanins.

Hepatoprotective and Antioxidant Effect of Mangifera Indica Leaf Extracts against Mercuric Chloride-induced Liver Toxicity in Mice

PubMed Central

Karuppanan, Muthupillai; Krishnan, Manigandan; Padarthi, Pavankumar

2014-01-01

ABSTRACT Background To explore the antioxidant and hepatoprotective effect of ethanolic Mangifera indica (EMI) and methanolic Mangifera indica (MMI) leaf extracts in mercuric chloride (HgCl2) induced toxicity in Swiss albino mice. Materials and methods Toxicity in mice was induced with HgCl2 (5.0 mg/kg, i.p.), followed by oral intervention with EMI and MMI extracts (25 mg and 50 mg/kg. body wt.) for 30 days. Results and discussion The extent of liver damage was assessed from the extents of histopathological, morphological, antioxidant and liver enzymes. Mercuric chloride-induced mice showed an increased cellular damage whereas leaf extracts of EMI and MMI-treated mice showed recovery of damaged hepatocytes. Mercuric chloride intoxicated mice exhibited a significant (p < 0.05) elevation in the liver enzymes (Aspartate amino transferase and Alanine amino transferase) and gradual decline in the cellular radical scavenging enzyme levels (Catalase, Glutathione-s-transferase and Glutathione peroxidase. The combined treatment with EMI and MMI leaf extracts significantly (p < 0.05) reversed these parameters. However, the effects of MMI leaf extract (50 mg/kg) were superior to those of EMI- treated mice possibly due to its potent radical scavenging property. These results suggest that oral supplementation of Mangifera indica extract remarkably reduces hepatotoxicity in mice possibly through its antioxidant potentials. How to cite this article: Karuppanan M, Krishnan M, Padarthi P, Namasivayam E. Hepatoprotec-tive and Antioxidant Effect of Mangifera Indica Leaf Extracts against Mercuric Chloride-induced Liver Toxicity in Mice. Euroasian J Hepato-Gastroenterol 2014;4(1):18-24. PMID:29264314

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 proliferation, which are both critical to atherogenesis.

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.

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 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.

BIOTRANSFORMATION AND GENOTOXICITY OF THE DRINKING WATER DISINFECTION BYPRODUCT BROMODICHLOROMETHANE: DNA BINDING MEDIATED BY GLUTATHIONE TRANSFERASE THETA 1-1

EPA Science Inventory

The drinking water disinfection byproduct bromodichloromethane (CHBrCl2) was
previously shown to be mutagenic in Salmonella typhimurium that overexpress rat glutathione
transferase theta 1-1 (GSTT1-1). Several experimental approaches were undertaken in this study
to inve...

Protective role of Scoparia dulcis plant extract on brain antioxidant status and lipidperoxidation in STZ diabetic male Wistar rats.

PubMed

Pari, Leelavinothan; Latha, Muniappan

2004-11-02

The aim of the study was to investigate the effect of aqueous extract of Scoparia dulcis on the occurrence of oxidative stress in the brain of rats during diabetes by measuring the extent of oxidative damage as well as the status of the antioxidant defense system. Aqueous extract of Scoparia dulcis plant was administered orally (200 mg/kg body weight) and the effect of extract on blood glucose, plasma insulin and the levels of thiobarbituric acid reactive substances (TBARS), hydroperoxides, superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione-S-transferase (GST) and reduced glutathione (GSH) were estimated in streptozotocin (STZ) induced diabetic rats. Glibenclamide was used as standard reference drug. A significant increase in the activities of plasma insulin, superoxide dismutase, catalase, glutathione peroxidase, glutathione-S-transferase and reduced glutathione was observed in brain on treatment with 200 mg/kg body weight of Scoparia dulcis plant extract (SPEt) and glibenclamide for 6 weeks. Both the treated groups showed significant decrease in TBARS and hydroperoxides formation in brain, suggesting its role in protection against lipidperoxidation induced membrane damage. Since the study of induction of the antioxidant enzymes is considered to be a reliable marker for evaluating the antiperoxidative efficacy of the medicinal plant, these findings suggest a possible antiperoxidative role for Scoparia dulcis plant extract. Hence, in addition to antidiabetic effect, Scoparia dulcis possess antioxidant potential that may be used for therapeutic purposes.

Induction of hepatic antioxidants in freshwater catfish (Channa punctatus Bloch) is a biomarker of paper mill effluent exposure.

PubMed

Ahmad, I; Hamid, T; Fatima, M; Chand, H S; Jain, S K; Athar, M; Raisuddin, S

2000-09-01

Enzymatic and non-enzymatic antioxidants serve as an important biological defense against environmental oxidative stress. Information on antioxidant defense in fish is meager despite that fish are constantly exposed to a myriad of environmental stress including the oxidants. This study, therefore, assesses the activities of antioxidant enzymes viz., glutathione peroxidase, catalase and glutathione S-transferase and the non-enzymatic antioxidants viz., glutathione and metallothionein in various tissues of freshwater fish Channa punctatus (Bloch), in response to short-term and long-term exposures to paper mill effluent. The fish were exposed to the effluent at a concentration of 1.0% (v/v) for 15, 30, 60 and 90 days. The exposure caused a time-dependent increase in glutathione level (P < 0.001), activities of glutathione peroxidase (P < 0.05 to P < 0.001), glutathione S-transferase (P < 0.001) and a marginal initial decrease in catalase activity in the liver (P < 0.01 to P < 0.001). Metallothionein was induced in liver after 60 days of exposure. Two isoforms of metallothionein were detected. Catalase activity also increased 60 days afterwards. Antioxidant pattern was different in gill and kidney showing that liver was more resistant to oxidative damage as compared to gills and kidney. Our results demonstrate a pollutant-induced adaptive response in fish. In addition, levels of enzymatic and non-enzymatic tissue antioxidants may serve as surrogate markers of exposure to oxidant pollutants in fish.

Hydrogen saline prevents selenite-induced cataract in rats

PubMed Central

Yang, Chun-xiao; Ding, Tian-bing

2013-01-01

Purpose The aim of this study was to investigate the potential antioxidative effect and mechanism for the protective effects of hydrogen saline on selenite-induced cataract in rats. Methods Sprague-Dawley rat pups were divided into the following groups: control (Group A), selenite induced (Group B), and selenite plus hydrogen saline treated (Group C). Rat pups in Groups B and C received a single subcutaneous injection of sodium selenite (25 μmol/kg bodyweight) on postnatal day 12. Group C also received an intraperitoneal injection of H2 saline (5 ml/kg bodyweight) daily from postnatal day 8 to postnatal day 17. The development of cataract was assessed weekly by slit-lamp examination for 2 weeks. After sacrifice, extricated lenses were analyzed for activities of superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, and glutathione S-transferase, levels of malondialdehyde, reduced glutathione (GSH), and total sulfhydryl contents. Results The magnitude of lens opacification in Group B was significantly higher than in Group A (p<0.05), while Group C had less opacification than Group B (p<0.05). Compared with Group B, the mean activities of the antioxidant enzymes superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, and glutathione S-transferase, levels of GSH, and total sulfhydryl contents were higher, whereas the level of malondialdehyde was lower following treatment with hydrogen saline(p<0.05). Conclusions This is an initial report showing that hydrogen saline can prevent selenite-induced cataract in rats. It acts via maintaining antioxidant enzymes and GSH, protecting the sulfhydryl group, and inhibiting lipid peroxidation. PMID:23922487

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.

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.

Adipokinetic hormone-induced antioxidant response in Spodoptera littoralis.

PubMed

Večeřa, Josef; Krishnan, Natraj; Mithöfer, Axel; Vogel, Heiko; Kodrík, Dalibor

2012-03-01

The antioxidative potential of the Manduca sexta adipokinetic hormone (Manse-AKH) in the last instar larvae of Spodoptera littoralis (Noctuidae, Lepidoptera) was demonstrated after exposure to oxidative stress (OS) elicited by feeding on artificial diet containing tannic acid (TA). Determination of protein carbonyls (PCs) and reduced glutathione (GSH) levels, monitoring of activity of antioxidant enzymes catalase (CAT), superoxide dismutase (SOD) and glutathione-S-transferases (GSTs), as well as measuring of the mRNA expression of CAT and SOD were used as markers of the OS. Injection of the Manse-AKH (5 pmol per individual) reversed the OS status by mitigation of PCs formation and by stimulation of glutathione-S-transferases (GSTs) activity. The CAT and SOD mRNA expression was significantly suppressed after the Manse-AKH injection while activity of these enzymes was not affected. These results indicate that diminishing of OS after the AKH injection might be a result of activation of specific enzymatic pathway possibly at the post-translational level rather than a direct effect on regulation of antioxidant marker genes at the transcriptional level. Copyright © 2011 Elsevier Inc. All rights reserved.

Glutathione S-transferase M1 (GSTM1) null genotype and coronary artery disease risk: a meta-analysis

PubMed Central

Zhang, Zhen-Xian; Zhang, Ye

2014-01-01

Background: The Glutathione S-Transferase M1 (GSTM1) null genotype has been indicated to be correlated with coronary artery disease (CAD) susceptibility, but study results are still debatable. Thus, a meta-analysis was conducted. Materials and methods: Databases including PubMed, Embase, Web of Science, and Chinese National Knowledge Infrastructure (CNKI) were searched. Data were extracted and pooled odds ratios (OR) with 95% confidence intervals (CI) were calculated. Results: Twenty-six studies with 10595 cases and 13782 controls were included in this meta-analysis. The association between GSTM1 null genotype and CAD risk was significant (OR = 1.35; 95% CI, 1.09 - 1.67; P < 0.01). When stratified by ethnicity, the significantly elevated risk were observed in Caucasians (OR = 1.39; 95% CI, 1.07 - 1.81; P = 0.01) but not in Asians (OR = 1.27; 95% CI, 0.87 - 1.86; P = 0.22). No significantly increased myocardial infarction risk was observed (OR = 0.96; 95% CI, 0.78 - 1.18; P = 0.68). Subgroup analysis on the smoking status showed that the increased risk was found in smokers (OR = 1.66; 95% CI, 1.14 - 2.42; P < 0.01) but not in non-smokers (OR = 1.30; 95% CI, 1.74 - 2.28; P = 0.37). Conclusion: In conclusion, this meta-analysis suggested that GSTM1 null genotype was a risk factor for CAD, especially in Caucasians and smokers. PMID:25419371

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

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

Preliminary X-ray crystallographic analysis of glutathione transferase zeta 1 (GSTZ1a-1a)

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

Boone, Christopher D.; Zhong, Guo; Smeltz, Marci

2014-01-21

Crystals of glutathione transferase zeta 1 were grown and shown to diffract X-rays to 3.1 Å resolution. They belonged to space group P1, with unit-cell parameters a = 42.0, b = 49.6, c = 54.6 Å, α = 82.9, β = 69.9, γ = 73.4°.

Alterations in Glutathione S-transferase pi expression following exposure to MPP+-induced oxidative stress in blood of Parkinson’s disease patients

PubMed Central

Korff, Ane; Pfeiffer, Brenda; Smeyne, Michelle; Kocak, Mehmet; Pfeiffer, Ronald F.

2012-01-01

The major motor symptoms of Parkinson’s disease do not occur until a majority of the dopaminergic neurons in the midbrain SNpc have already died. For this reason, it is critical to identify biomarkers that will allow for the identification of presymptomatic individuals. In this study, we examine the baseline expression of the antioxidant protein Glutathione S-transferase pi (GSTpi) in blood of PD and environmental and age-matched controls and compare it to GSTpi levels following exposure to 1-methyl-4-phenylpyridinium (MPP+), an agent that has been shown to induce oxidative stress. We find that 4 hours of exposure to MPP+, significant increases in GSTpi levels can be observed in the leukocytes of PD patients. No changes were seen in other blood components. This suggests that GSTpi and potentially other members of this and other anti-oxidant families may be viable biomarkers for PD. PMID:21840241

Probing the active site of alpha-class rat liver glutathione S-transferases using affinity labeling by monobromobimane.

PubMed Central

Hu, L.; Borleske, B. L.; Colman, R. F.

1997-01-01

Monobromobimane (mBBr) is a substrate of both mu- and alpha-class rat liver glutathione S-transferases, with Km values of 0.63 microM and 4.9 microM for the mu-class isozymes 3-3 and 4-4, respectively, and 26 microM for the alpha-class isozymes 1-1 and 2-2. In the absence of substrate glutathione, mBBr acts as an affinity label of the 1-1 as well as mu-class isozymes, but not of the alpha-class 2-2 isozyme. Incubation of rat liver isozyme 1-1 with mBBr at pH 7.5 and 25 degrees C results in a time-dependent inactivation of the enzyme but at a slower (threefold) rate than for reactions with the mu-class isozyme 3-3 and 4-4. The rate of inactivation of 1-1 isozyme by mBBr is not decreased but, rather, is slightly enhanced by S-methyl glutathione. In contrast, 17 beta-estradiol-3,17-disulfate (500 microM) gives a 12.5-fold decrease in the observed rate constant of inactivation by 4 mM mBBr. When incubated for 60 min with 4 mM mBBr, the 1-1 isozyme loses 60% of its activity and incorporates 1.7 mol reagent/mol subunit. Peptide analysis after thermolysin digestion indicates that mBBr modification is equally distributed between two cysteine residues at positions 17 and 111. Modification at these two sites is reduced equally in the presence of the added protectant, 17 beta-estradiol-3,17-disulfate, suggesting that Cys 17 and Cys 111 reside within or near the enzyme's steroid binding sites. In contrast to the 1-1 isozyme, the other alpha-class isozyme (2-2) is not inactivated by mBBr at concentrations as high as 15 mM. The different reaction kinetics and modification sites by mBBr suggest that distinct binding site structures are responsible for the characteristic substrate specificities of glutathione S-transferase isozymes. PMID:9007975

Probing the active site of alpha-class rat liver glutathione S-transferases using affinity labeling by monobromobimane.

PubMed

Hu, L; Borleske, B L; Colman, R F

1997-01-01

Monobromobimane (mBBr) is a substrate of both mu- and alpha-class rat liver glutathione S-transferases, with Km values of 0.63 microM and 4.9 microM for the mu-class isozymes 3-3 and 4-4, respectively, and 26 microM for the alpha-class isozymes 1-1 and 2-2. In the absence of substrate glutathione, mBBr acts as an affinity label of the 1-1 as well as mu-class isozymes, but not of the alpha-class 2-2 isozyme. Incubation of rat liver isozyme 1-1 with mBBr at pH 7.5 and 25 degrees C results in a time-dependent inactivation of the enzyme but at a slower (threefold) rate than for reactions with the mu-class isozyme 3-3 and 4-4. The rate of inactivation of 1-1 isozyme by mBBr is not decreased but, rather, is slightly enhanced by S-methyl glutathione. In contrast, 17 beta-estradiol-3,17-disulfate (500 microM) gives a 12.5-fold decrease in the observed rate constant of inactivation by 4 mM mBBr. When incubated for 60 min with 4 mM mBBr, the 1-1 isozyme loses 60% of its activity and incorporates 1.7 mol reagent/mol subunit. Peptide analysis after thermolysin digestion indicates that mBBr modification is equally distributed between two cysteine residues at positions 17 and 111. Modification at these two sites is reduced equally in the presence of the added protectant, 17 beta-estradiol-3,17-disulfate, suggesting that Cys 17 and Cys 111 reside within or near the enzyme's steroid binding sites. In contrast to the 1-1 isozyme, the other alpha-class isozyme (2-2) is not inactivated by mBBr at concentrations as high as 15 mM. The different reaction kinetics and modification sites by mBBr suggest that distinct binding site structures are responsible for the characteristic substrate specificities of glutathione S-transferase isozymes.

Biochemical effects of nonylphenol polyethoxylate adjuvant, Diquat herbicide and their mixture on the three-spined stickleback (Gasterosteus aculeatus L.).

PubMed

Sanchez, W; Palluel, O; Lagadic, L; Aït-Aïssa, S; Porcher, J-M

2006-07-01

This study examined the response of 7-ethoxyresorufine-O-deethylase, glutathione-S-transferase, glutathione peroxidase, glutathione content, level of thiobarbituric acid reactive compounds and circulating vitellogenin, in three-spined sticklebacks after 21 days of exposure to Diquat herbicide, commercial nonylphenol polyethoxylate adjuvant and mixture between Diquat and adjuvant. The results showed that adjuvant exerted more important oxidative effects than Diquat and that mixture effects were unlike to single additivity. This study argues for ecotoxicological risk assessment of adjuvants and mixtures of adjuvants and pesticides.

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

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.

Oxidative stress enzyme and histopathological lesions in Colossoma macropomum (pisces, ariidae) for environmental impact assessment

NASA Astrophysics Data System (ADS)

Andrade, Ticianne de Sousa de Oliveira Mota; Sousa, Debora Batista Pinheiro; Dantas, Janaina Gomes; Castro, Jonatas da Silva; Neta, Raimunda Nonata Fortes Carvalho

2015-12-01

This study used oxidative stress enzyme (Glutathione S-Transferase and Catalase), histopathological lesions (Branchial lesions) and biometric data in the freshwater fish tambaqui, Colossoma macropomum, to assess environmental impacts in an Environmental Protection Area at São Luis, Brazil. Fish were sampled from two locations (A1 = contaminated area and A2 = reference site) within the protected area on four occasions. The activity of catalase (CAT) and glutathione S-transferase (GST) in C. macropomum was compared with biometric data and histopathological lesions. Results have shown that biometric data decreased significantly in fish (p<0.05) at the contaminated site. The activity of CAT was higher in fish specifically caught in A1. A significant difference was observed in the GST activity in the liver of C. macropomum when comparing fish from the contaminated site and those from the reference site (p<0.05).

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.

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

SKN-1-independent transcriptional activation of glutathione S-transferase 4 (GST-4) by EGF signaling

PubMed Central

Van de Walle, Pieter; Schoofs, Liliane

2016-01-01

ABSTRACT In C. elegans research, transcriptional activation of glutathione S-transferase 4 (gst-4) is often used as a read-out for SKN-1 activity. While many heed an assumed non-exclusivity of the GFP reporter signal driven by the gst-4 promoter to SKN-1, this is also often ignored. We here show that gst-4 can also be transcriptionally activated by EOR-1, a transcription factor mediating effects of the epidermal growth factor (EGF) pathway. Along with enhancing exogenous oxidative stress tolerance, EOR-1 inde-pendently of SKN-1 increases gst-4 transcription in response to augmented EGF signaling. Our findings caution researchers within the C. elegans community to always rely on sufficient experimental controls when assaying SKN-1 transcriptional activity with a gst-4p::gfp reporter, such as SKN-1 loss-of-function mutants and/or additional target genes next to gst-4. PMID:28090393

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.

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.

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.

Cold sensitivity in rice (Oryza sativa L.) is strongly correlated with a naturally occurring I99V mutation in the multifunctional glutathione transferase isoenzyme GSTZ2

USDA-ARS?s Scientific Manuscript database

GSTZs (zeta class glutathione transferases) belong to a highly conserved subfamily of soluble GSTs found in species ranging from fungi and plants to animals. GSTZ is identical to MAAI (maleylacetoacetate isomerase), which functions in tyrosine catabolism by catalyzing the isomerization of MAA (maley...

Monobromobimane as an affinity label of the xenobiotic binding site of rat glutathione S-transferase 3-3.

PubMed

Hu, L; Colman, R F

1995-09-15

Monobromobimane (mBBr), besides being a substrate in the presence of glutathione, inactivates rat liver glutathione S-transferase 3-3 at pH 7.5 and 25 degrees C as assayed using 1-chloro-2,4-dinitrobenzene (CDNB). The rate of inactivation is enhanced about 5-fold by S-methylglutathione. Substrate analogs bromosulfophthalein and 2,4-dinitrophenol decrease the rate of inactivation at least 20-fold. Upon incubation for 60 min with 0.25 mM mBBr and S-methylglutathione, the enzyme loses 91% of its activity toward CDNB and incorporates 2.14 mol of reagent/mol of subunit, whereas incubation under the same conditions but with added protectant 2,4-dinitrophenol yields an enzyme that is catalytically active and contains only 0.89 mol of reagent/mol of subunit. mBBR-modified enzyme is fluorescent, and fluorescence energy transfer occurs between intrinsic tryptophan and covalently bound bimane in modified enzyme. Both Tyr115 and Cys114 are modified, but Tyr115 is the initial reaction target and its modification correlates with loss of activity toward CDNB. The fact that the activity toward mBBr is retained by the enzyme after modification suggests that rat isozyme 3-3 has two binding sites for mBBr.

Downregulation of glutathione S-transferase pi in asthma contributes to enhanced oxidative stress.

PubMed

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; Hershey, Gurjit K Khurana

2011-09-01

Glutathione S-transferase pi (GSTPi) is the predominant redox regulator in the lung. Although evidence implicates an important role for GSTPi in asthma, the mechanism for this has remained elusive. We sought to determine how GSTPi is regulated in asthma and to elucidate its role in maintaining redox homeostasis. We elucidated the regulation of GSTPi in children with asthma and used murine models of asthma to determine the role of GSTPi in redox homeostasis. Our findings demonstrate that GSTPi transcript levels are markedly downregulated in allergen- and IL-13-treated murine models of asthma through signal transducer and activator of transcription 6-dependent and independent pathways. Nuclear factor erythroid 2-related factor 2 was also downregulated in these models. The decrease in GSTPi expression was associated with decreased total glutathione S-transferase activity in the lungs of mice. Examination of cystine intermediates uncovered a functional role for GSTPi in regulating cysteine oxidation, whereby GSTPi-deficient mice exhibited increased oxidative stress (increase in percentage cystine) compared with wild-type mice after allergen challenge. GSTPi expression was similarly downregulated in children with asthma. These data collectively suggest that downregulation of GSTPi after allergen challenge might contribute to the asthma phenotype because of disruption of redox homeostasis and increased oxidative stress. Furthermore, GSTPi might be an important therapeutic target for asthma, and evaluation of GSTPi expression might prove beneficial in identifying patients who would benefit from therapy targeting this pathway. Copyright © 2011 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved.

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.

Interactive effects of antioxidant genes and air pollution on respiratory function and airway disease: a HuGE review.

PubMed

Minelli, Cosetta; Wei, Igor; Sagoo, Gurdeep; Jarvis, Debbie; Shaheen, Seif; Burney, Peter

2011-03-15

Susceptibility to the respiratory effects of air pollution varies between individuals. Although some evidence suggests higher susceptibility for subjects carrying variants of antioxidant genes, findings from gene-pollution interaction studies conflict in terms of the presence and direction of interactions. The authors conducted a systematic review on antioxidant gene-pollution interactions which included 15 studies, with 12 supporting the presence of interactions. For the glutathione S-transferase M1 gene (GSTM1) (n=10 studies), only 1 study found interaction with the null genotype alone, although 5 observed interactions when GSTM1 was evaluated jointly with other genes (mainly NAD(P)H dehydrogenase [quinone] 1 (NQO1)). All studies on the glutathione S-transferase P1 (GSTP1) Ile105Val polymorphism (n=11) provided some evidence of interaction, but findings conflicted in terms of risk allele. Results were negative for glutathione S-transferase T1 (GSTT1) (n=3) and positive for heme oxygenase 1 (HMOX-1) (n=2). Meta-analysis could not be performed because there were insufficient data available for any specific gene-pollutant-outcome combination. Overall the evidence supports the presence of gene-pollution interactions, although which pollutant interacts with which gene is unclear. However, issues regarding multiple testing, selective reporting, and publication bias raise the possibility of false-positive findings. Larger studies with greater accuracy of pollution assessment and improved quality of conduct and reporting are required. © The Author 2011. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved.

Response of detoxification system genes on Chironomus riparius aquatic larvae after antibacterial agent triclosan exposures.

PubMed

Martínez-Paz, Pedro

2018-05-15

Triclosan (TCS) is an antimicrobial agent used in a range of personal care and consumer products and is commonly detected in aquatic ecosystems. In the present study, the effects of TCS at the molecular level on the detoxification system of Chironomus riparius aquatic larvae, a test organism widely used for the assessment of aquatic toxicology, were evaluated. The obtained results show that this xenobiotic was able to induce significant changes in transcripts from different cytochrome P450s and glutathione s-transferases genes, involved in phase I and phase II of detoxification system, respectively. In contrast, TCS did not affect the glutathione S-transferase enzyme activity nor the expression pattern of multidrug resistance-associated protein 1, which belongs to phase III of detoxification system. These results provide information about the effects of TCS on the detoxification mechanism of C. riparius and offers different biomarker genes that could be useful in ecotoxicological studies, risk assessment and bioremediation. Copyright © 2017 Elsevier B.V. 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.

Diphenylmethyl selenocyanate attenuates malachite green induced oxidative injury through antioxidation & inhibition of DNA damage in mice

PubMed Central

Das, Jayanta Kumar; Sarkar, Sibani; Hossain, Sk Ugir; Chakraborty, Pramita; Das, Rajat Kumar; Bhattacharya, Sudin

2013-01-01

Background & objectives: Malachite green (MG), an environmentally hazardous material, is used as a non permitted food colouring agent, especially in India. Selenium (Se) is an essential nutritional trace element required for animals and humans to guard against oxidative stress induced by xenobiotic compounds of diverse nature. In the present study, the role of the selenium compound diphenylmethyl selenocyanate (DMSE) was assessed on the oxidative stress (OS) induced by a food colouring agent, malachite green (MG) in vivo in mice. Methods: Swiss albino mice (Mus musculus) were intraperitoneally injected with MG at a standardized dose of 100 μg/ mouse for 30 days. DMSE was given orally at an optimum dose of 3 mg/kg b.w. in pre (15 days) and concomitant treatment schedule throughout the experimental period. The parameters viz. ALT, AST, LPO, GSH, GST, SOD, CAT, GPx, TrxR, CA, MN, MI and DNA damage have been evaluated. Results: The DMSE showed its potential to protect against MG induced hepatotoxicity by controlling the serum alanine aminotransferase and aspartate amino transferase (ALT and AST) levels and also ameliorated oxidative stress by modulating hepatic lipid peroxidation and different detoxifying and antioxidative enzymes such as glutathione-S-transferase (GST), superoxide dismutase (SOD), catalase (CAT), and also the selenoenzymes such as glutathione peroxidase (GPx) and thioredoxin reductase (TrxR) and reduced glutathione level which in turn reduced DNA damage. Interpretation & conclusions: The organo-selenium compound DMSE showed significant protection against MG induced heptotoxicity and DNA damage in murine model. Better protection was observed in pretreatment group than in the concomitant group. Further studies need to be done to understand the mechanism of action. PMID:23852297

Sphingobium sp. SYK-6 LigG involved in lignin degradation is structurally and biochemically related to the glutathione transferase ω class.

PubMed

Meux, Edgar; Prosper, Pascalita; Masai, Eiji; Mulliert, Guillermo; Dumarçay, Stéphane; Morel, Mélanie; Didierjean, Claude; Gelhaye, Eric; Favier, Frédérique

2012-11-16

SpLigG is one of the three glutathione transferases (GSTs) involved in the process of lignin breakdown in the soil bacterium Sphingobium sp. SYK-6. Sequence comparisons showed that SpLigG and several proteobacteria homologues form an independent cluster within cysteine-containing GSTs. The relationship between SpLigG and other GSTs was investigated. The X-ray structure and biochemical properties of SpLigG indicate that this enzyme belongs to the omega class of glutathione transferases. However, the hydrophilic substrate binding site of SpLigG, together with its known ability to stereoselectively deglutathionylate the physiological substrate α-glutathionyl-β-hydroxypropiovanillone, argues for broadening the definition of the omega class. Copyright © 2012 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

[INFLUENCE OF MEDICINAL PLANT EXTRACTS ON THE FUNCTIONS AND ANTIOXIDANT PROTECTION OF ERYTHROCYTES IN RATS WITH EXPERIMENTAL DIABETES MELLITUS].

PubMed

Vengerovskii, A I; Yakimova, T V; Nasanova, O N

2016-01-01

Experiments on rats with diabetes mellitus model induced by streptosotocin and high (30%) fat diet showed that the daily treatment with aqueous extracts of great nettle leaves (100 mg/kg) and common burdock roots (25 mg/kg) for a period of 10 days led to a decrease in the glycemic index and triglyceride level and produced protective action on erythrocytes both in animals kept on a fat-rich diet and on the background of a low-caloric ration. Both medicinal plant extracts were comparable with reference drug metformin in reducing the concentration of glycosylated hemoglobin (by 12-31%) and ectoglobular hemoglobin (1.7-1.8 times, p <0.05), decreasing the content of malonic dialdehyde in erythrocytes (1.3 times, p < 0.05), and increasing erythrocyte deformability (1.3-1.4 times, p < 0.05) and activity of their antioxidant enzymes glutathione peroxidase, glutathione reductase, glutathione-S-transferase, catalase, and supe- roxide dismutase (1.2-2.6 times, p < 0.05). A diet with usual (8%) fat content improved the metabolic indices to a lower degree (on the average by 13-21%, p < 0.05) than did the proposed phytotherapy.

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.

Indigofera suffruticosa Mill extracts up-regulate the expression of the π class of glutathione S-transferase and NAD(P)H: quinone oxidoreductase 1 in rat Clone 9 liver cells.

PubMed

Chen, Chun-Chieh; Liu, Chin-San; Li, Chien-Chun; Tsai, Chia-Wen; Yao, Hsien-Tsung; Liu, Te-Chung; Chen, Haw-Wen; Chen, Pei-Yin; Wu, Yu-Ling; Lii, Chong-Kuei; Liu, Kai-Li

2013-09-01

Because induction of phase II detoxification enzyme is important for chemoprevention, we study the effects of Indigofera suffruticosa Mill, a medicinal herb, on the expression of π class of glutathione S-transferase (GSTP) and NAD(P)H: quinone oxidoreductase 1 (NQO1) in rat Clone 9 liver cells. Both water and ethanolic extracts of I. suffruticosa significantly increased the expression and enzyme activities of GSTP and NQO1. I. suffruticosa extracts up-regulated GSTP promoter activity and the binding affinity of nuclear factor erythroid 2-related factor 2 (Nrf2) with the GSTP enhancer I oligonucleotide. Moreover, I. suffruticosa extracts increased nuclear Nrf2 accumulation as well as ARE transcriptional activity. The level of phospho-ERK was augmented by I. suffruticosa extracts, and the ERK inhibitor PD98059 abolished the I. suffruticosa extract-induced ERK activation and GSTP and NQO-1 expression. Moreover, I. suffruticosa extracts, especially the ethanolic extract increased the glutathione level in mouse liver and red blood cells as well as Clone 9 liver cells. The efficacy of I. suffruticosa extracts in induction of phase II detoxification enzymes and glutathione content implies that I. suffruticosa could be considered as a potential chemopreventive agent. Copyright © 2013 Elsevier Ltd. All rights reserved.

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.

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.

Biochemical and genotoxic response of naphthalene to fingerlings of milkfish Chanos chanos.

PubMed

Palanikumar, L; Kumaraguru, A K; Ramakritinan, C M

2013-09-01

The present study investigated the acute toxicity, sub-lethal toxicity and biochemical response of naphthalene in fingerlings of milkfish Chanos chanos. The 96 h acute toxicity LC50 values for C. chanos exposed to naphthalene was 5.18 μg l(-1). The estimated no observed effect concentration and lowest observed effect concentration values for naphthalene in C. chanos were 0.42 and 0.69 μg l(-1) respectively for 30 days. The estimated maximum allowable toxicant concentration for naphthalene was 0.53 μg l(-1). Biochemical enzyme markers such as lipid peroxidation, catalase, glutathione S transferase and reduced glutathione were measured in gills and liver tissues of C. chanos exposed to sub-lethal concentrations of naphthalene. Fluctuation in lipid peroxidation and catalase level suggests that naphthalene concentrations play a vital role in induction of oxidative stress in fish. Induction of reduced glutathione level and inhibition of glutathione S-transferase level was observed in naphthalene exposed C. chanos suggesting that there may be enhanced oxidative damage due to free radicals. Increasing concentration increases in number of nuclear abnormalities. The formation of micronuclei and binucleated micronuclei induction by naphthalene confirm its genotoxic potential. The highest levels of DNA damage (% tail length) were observed at 1.24 μg l(-1) of naphthalene. The study suggests that biochemical enzymes, nuclear abnormalities and DNA damage index can serve as a biological marker for naphthalene contamination.

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

Are polymorphisms in metabolism protective or a risk for reduced white blood cell counts in a Chinese population with low occupational benzene exposures?

PubMed Central

Ye, Ling-li; Zhang, Guang-hui; Huang, Jing-wen; Li, Yong; Zheng, Guo-qiao; Zhang, De-ting; Zhou, Li-fang; Tao, Xi-dan; Zhang, Jing; Ye, Yun-jie; Sun, Pin; Frank, Arthur; Xia, Zhao-lin

2015-01-01

Background: Genetic variations in metabolic enzyme genes may enhance hematotoxicity in benzene-exposed populations. Objective: To investigate the association between polymorphisms of metabolism genes and white blood cells (WBCs). Methods: Three hundred and eighty-five benzene-exposed workers and 220 unexposed indoor workers were recruited in China. We explored the relationship between metabolic enzymes polymorphisms [glutathione S-transferase T1/M1 (GSTT1/M1) null, glutathione S-transferase P1 (GSTP1)rs1695, Cytochrome P450 2E1 (CYP2E1) rs3813867, rs2031920, rs6413432, microsomal epoxide hydrolase (mEH) rs1051740, rs2234922] by polymerase chain reaction (PCR)–restriction fragment length polymorphism (RFLP) analysis and WBC. Results: The exposed group had lower WBC counts (P<0.001) than the unexposed group. Increased susceptibility to hematotoxicity, as evidenced by lower WBC counts, was found in workers with null-GSTT1 (P = 0.045), null-GSTM1 (P = 0.030), rs2031920 (P = 0.020), and rs3813867 (P = 0.014) genotypes. White blood cell counts were also lower in workers with null-GSTT1 and null-GSTM after adjusting for age, gender, smoking, and alcohol consumption. Conclusion: Null-GSTT1 and null-GSTM1 genotypes and Cytochrome P4502E1 (CYP2E1: rs2031920, rs3813867) may support the hematotoxicity of benzene-exposed workers in China, and we can make use of it to select susceptible population. PMID:26179485

Gluthathione-S-transferase M1 regulation of diesel exhaust particle-induced pro-inflammatory mediator expression in normal human bronchial epithelial cells

EPA Science Inventory

Diesel exhaust particles (DEP) contribute substantially to ambient particulate matter (PM) air pollution in urban areas. Inhalation of PM has been associated with increased incidence of lung disease in susceptible populations. We have demonstrated that the glutathione-S-transfera...

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.

Effects of genetic polymorphisms of glutathione S-transferase genes (GSTM1, GSTT1, GSTP1) on the risk of diabetic nephropathy: a meta-analysis.

PubMed

Orlewski, Jan; Orlewska, Ewa

2015-01-01

Glutathione S-transferases (GSTs) belong to a family of ubiquitous and multifunctional enzymes that protect the cells against oxidative stress. The aim of the study was to evaluate the association between the polymorphisms of glutathione-S-transferase (GST) genes and diabetic nephropathy (DN). PubMed, EMBASE, and Google Scholar databases were systematically searched to identify relevant studies. The odds ratio (OR) for the association was determined using a fixed or random effects model. Tests for heterogeneity of the results and sensitivity analyses were performed. A total of 9 publications (874 patients in the study group, 966 controls) were included. With the exception of 1 study, GSTT1 and GSTM1 genotypes were not assessed by methods that measure a gene copy number. A significantly increased risk of DN was found for the GSTM1(-) genotype (OR, 1.27; 95% CI, 1.02-1.58) and the combination of GSTT1(-)/GSTM1(-) (OR,2.02; 95% CI, 1.22-3.36). We did not observe a correlation between DN and the GSTT1(-) genotype or the presence of Val alleles. In a subgroup analysis, an association between DN and the GSTM1(-) genotype was significant in Asians but not in Caucasians. Our results indicate that the GSTM1(-) genotype and the combination of GSTT1(-)/GSTM1(-) increase the risk of DN. The combination of the GST polymorphisms rather than individual polymorphismshould be investigated. Genotyping allowing a trimodular determination of the GST copy number variations may better describe an association between the risk of disease and a given genotype.

Up-regulation of CYP1A1 and phase II enzymes by 5-ring isomeric polycyclic aromatic hydrocarbons in precision-cut rat hepatic slices: Importance of molecular shape.

PubMed

Pushparajah, Daphnee; Lewis, Dfv; Ioannides, Costas

2017-04-01

The objectives of the present study were two-fold: (a) to evaluate the role of molecular shape on the interaction of polycyclic aromatic hydrocarbons (PAHs) with the Ah receptor and CYP1A1 upregulation, and (b) to evaluate the potential of PAHs to induce epoxide hydrolase and glutathione S-transferase, two major enzymes involved in their metabolism. In order to achieve these objectives, precision-cut rat liver slices were incubated with a range of concentrations of seven 5-ring isomeric PAHs, namely benzo[c]chrysene, benzo[b]chrysene, benzo[g]chrysene, dibenzo[a,j]anthracene, dibenzo[a,c]anthracene, picene and pentacene, for 24h. All compounds, with the exception of pentacene, elevated the O-deethylation of ethoxyresorufin, an activity associated with CYP1A1; induction of this enzyme by the various PAHs correlated with their avidity for the Ah receptor. None of the PAHs studied increased epoxide hydrolase activity, monitored using benzo[a]pyrene 4,5-oxide. Of the seven PAHs, only benzo[g]chrysene elevated glutathione S-transferase activity, measured using 1-chloro-2,4-dinitrobenzene or 7-chloro-4-nitrobenzo-2-oxa-1,3-diazole as substrates. No relationship could be established between length or length/width and interaction with the Ah receptor and CYP1A1 up-regulation indicating that other structural or electronic factors are likely to be more important. Finally, 5-ring PAHs are poor inducers of the epoxide hydrolase and glutathione S-transferase enzyme systems. Copyright © 2017 Elsevier Ltd. All rights reserved.

Glutathione -S-Transferase μ 1 Regulates Vascular Smooth Muscle Cell Proliferation, Migration, and Oxidative Stress

PubMed Central

Yang, Yanqiang; Parsons, Kelly K.; Chi, Liqun; Malakauskas, Sandra M.; Le, Thu H.

2009-01-01

Glutathione S-transferase μ-1, GSTM1, belongs to a superfamily of glutathione-S-transferases that metabolize a broad range of reactive oxygen species (ROS) and xenobiotics. Across species, genetic variants that result in decreased expression of the Gstm1 gene are associated with increased susceptibility for vascular diseases, including atherosclerosis in humans. We previously identified Gstm1 as a positional candidate in our gene mapping study for susceptibility to renal vascular injury characterized by medial hypertrophy and hyperplasia of the renal vessels. To determine the role of Gstm1 in vascular smooth muscle cells (VSMCs), we isolated VSMCs from mouse aortas. We demonstrate that VSMCs from the susceptible C57BL/6 mice have reduced expression of Gstm1 mRNA and its protein product compared to that of the resistant 129 mice. After serum stimulation, C57BL/6 VSMCs proliferate and migrate at a much faster rate than 129 VSMCs. Furthermore, C57BL/6 VSMCs have higher levels of ROS, and exhibit exaggerated p38 MAPK phosphorylation after exposure to H2O2. To establish causality, we show that knockdown of Gstm1 by siRNA results in increased proliferation of VSMCs in a dose dependent manner, as well as in increased ROS levels and VSM cell migration. Moreover, Gstm1 siRNA causes increased p38 MAPK phosphorylation, and attenuates the anti-proliferative effect of TEMPOL. Our data suggest that Gstm1 is a novel regulator of VSMC proliferation and migration through its role in handling ROS. Genetic variants that cause a decremental change in expression of Gstm1 may permit an environment of exaggerated oxidative stress, leading to susceptibility to vascular remodeling and atherosclerosis. PMID:19822795

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

Effects of Ozone Oxidative Preconditioning on TNF-α Release and Antioxidant-Prooxidant Intracellular Balance in Mice During Endotoxic Shock

PubMed Central

Zamora, Zullyt B.; Borrego, Aluet; López, Orlay Y.; Delgado, René; González, Ricardo; Menéndez, Silvia; Hernández, Frank; Schulz, Siegfried

2005-01-01

Ozone oxidative preconditioning is a prophylactic approach, which favors the antioxidant-prooxidant balance for preservation of cell redox state by the increase of antioxidant endogenous systems in both in vivo and in vitro experimental models. Our aim is to analyze the effect of ozone oxidative preconditioning on serum TNF-α levels and as a modulator of oxidative stress on hepatic tissue in endotoxic shock model (mice treated with lipopolysaccharide (LPS)). Ozone/oxygen gaseous mixture which was administered intraperitoneally (0.2, 0.4, and 1.2 mg/kg) once daily for five days before LPS (0.1 mg/kg, intraperitoneal). TNF-α was measured by cytotoxicity on L-929 cells. Biochemical parameters such as thiobarbituric acid reactive substances (TBARS), enzymatic activity of catalase, glutathione peroxidase, and glutathione-S transferase were measured in hepatic tissue. One hour after LPS injection there was a significant increase in TNF-α levels in mouse serum. Ozone/oxygen gaseous mixture reduced serum TNF-α levels in a dose-dependent manner. Statistically significant decreases in TNF-α levels after LPS injection were observed in mice pretreated with ozone intraperitoneal applications at 0.2 (78%), 0.4 (98%), and 1.2 (99%). Also a significant increase in TBARS content was observed in the hepatic tissue of LPS-treated mice, whereas enzymatic activity of glutathion-S transferase and glutathione peroxidase was decreased. However in ozone-treated animals a significant decrease in TBARS content was appreciated as well as an increase in the activity of antioxidant enzymes. These results indicate that ozone oxidative preconditioning exerts inhibitory effects on TNF-α production and on the other hand it exerts influence on the antioxidant-prooxidant balance for preservation of cell redox state by the increase of endogenous antioxidant systems. PMID:15770062

Glutathione, glutathione-related enzymes, and oxidative stress in individuals with subacute occupational exposure to lead.

PubMed

Dobrakowski, Michał; Pawlas, Natalia; Hudziec, Edyta; Kozłowska, Agnieszka; Mikołajczyk, Agnieszka; Birkner, Ewa; Kasperczyk, Sławomir

2016-07-01

The aim of the study was to investigate the influence of subacute exposure to lead on the glutathione-related antioxidant defense and oxidative stress parameters in 36 males occupationally exposed to lead for 40±3.2days. Blood lead level in the examined population increased significantly by 359% due to lead exposure. Simultaneously, erythrocyte glutathione level decreased by 16%, whereas the activity of glutathione-6-phosphate dehydrogenase in erythrocytes and leukocytes decreased by 28% and 10%, respectively. Similarly, the activity of glutathione-S-transferase in erythrocytes decreased by 45%. However, the activity of glutathione reductase in erythrocytes and leukocytes increased by 26% and 6%, respectively, whereas the total oxidant status value in leukocytes increased by 37%. Subacute exposure to lead results in glutathione pool depletion and accumulation of lipid peroxidation products; however, it does not cause DNA damage. Besides, subacute exposure to lead modifies the activity of glutathione-related enzymes. Copyright © 2016 Elsevier B.V. All rights reserved.

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.

Computational QM/MM Study of the Reaction Mechanism of Human Glutathione S-Transferase A3-3

NASA Astrophysics Data System (ADS)

Calvaresi, Matteo; Stenta, Marco; Altoè, Piero; Bottoni, Andrea; Garavelli, Marco; Spinelli, Domenico

2007-12-01

Human Glutathione S-Transferase A3-3(hGSTA3-3) is the most efficient human steroid double-bond isomerase enzyme. It catalyzes the double bond isomerization of Δ5-androstene-3,17-dione (Δ5-AD) and Δ5-pregnene-3,20-dione (Δ5-PD). The isomerization products are the precursors of the steroid hormones testosterone and progesterone. We have carried out a QM/MM study to elucidate some interesting aspects of the enzyme catalytic mechanism. In particular, we have analyzed either a concerted or a stepwise reaction path. Moreover, we have attempted to rationalize the electrostatic effects on the catalytic activity of the residues surrounding the active site. Specifically, we have performed a "finger print" analysis to determine the electrostatic contribution of each aminoacid residue to the global electrostatic term, thus ranking the effect of the various aminoacids in the course of the reaction. In this way, we have highlighted the most important terms affecting the stabilization-destabilization of the enzyme.

Identification of an enhancer element of class Pi glutathione S-transferase gene required for expression by a co-planar polychlorinated biphenyl.

PubMed Central

Matsumoto, M; Imagawa, M; Aoki, Y

1999-01-01

3,3',4,4',5-Pentachlorobiphenyl (PenCB), one of the most toxic co-planar polychlorinated biphenyl congeners, specifically induces class Pi glutathione S-transferase (GSTP1) as well as cytochrome P-450 1A1 in primary cultured rat liver parenchymal cells [Aoki, Matsumoto and Suzuki (1993) FEBS Lett. 333, 114-118]. However, the 5'-flanking sequence of the GSTP1 gene does not contain a xenobiotic responsive element, to which arylhydrocarbon receptor binds. Using a chloramphenicol acetyltransferase assay we demonstrate here that the enhancer termed GSTP1 enhancer I (GPEI) is necessary for the stimulation by PenCB of GSTP1 gene expression in primary cultured rat liver parenchymal cells. GPEI is already known to contain a dyad of PMA responsive element-like elements oriented palindromically. It is suggested that a novel signal transduction pathway activated by PenCB contributes to the stimulation of GSTP1 expression. PMID:10051428

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

Alterations in glutathione S-transferase pi expression following exposure to MPP+ -induced oxidative stress in the blood of Parkinson's disease patients.

PubMed

Korff, Ane; Pfeiffer, Brenda; Smeyne, Michelle; Kocak, Mehmet; Pfeiffer, Ronald F; Smeyne, Richard Jay

2011-12-01

The major motor symptoms of Parkinson's disease do not occur until a majority of the dopaminergic neurons in the midbrain SNpc have already died. For this reason, it is critical to identify biomarkers that will allow for the identification of presymptomatic individuals. In this study, we examine the baseline expression of the anti-oxidant protein glutathione S-transferase pi (GSTpi) in the blood of PD patients and environmentally- and age-matched controls and compare it to GSTpi levels following exposure to 1-methyl-4-phenylpyridinium (MPP(+)), an agent that has been shown to induce oxidative stress. We find that after 4 h of exposure to MPP(+), significant increases in GSTpi levels can be observed in the leukocytes of PD patients. No changes were seen in other blood components. This suggests that GSTpi and potentially other members of this and other anti-oxidant families may be viable biomarkers for PD. Copyright © 2011 Elsevier Ltd. All rights reserved.

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.

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

Antimetastatic Effects of a Novel Telomerase Inhibitor, GRN163L, on Human Prostate Cancer

DTIC Science & Technology

2010-05-01

techniques such as identifi- cation of TMPRSS2:ERG fusion transcripts [4,5], Glutathione-S- transferase P1 ( GSTP1 ) gene promoter hypermethylation [6,7...telomerase activity and GSTP1 promoter methylation in ejaculate as potential screening tests for prostate cancer, Mol. Cell. Probes 14 (2000) 211–217. [7...C. Jeronimo, H. Usadel, R. Henrique, J. Oliveira, C. Lopes, W.G. Nelson, D. Sidransky, Quantitation of GSTP1 methylation in non-neoplastic prostatic

The human mitochondrial NADH: Ubiquinone oxidoreductase 51-kDa subunit oxidoreductase 51-kDa subunit maps adjacent to the glutathione S-transferase P1-1 gene on chromosome 11q13

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

Spencer, S.R.; Taylor, J.B.; Cowell, I.G.

The soluble glutathione transferases (GSTs) are a family of dimeric isoenymes catalyzing the conjugation of glutathione to hydrophobic electropiles. Their subunits can be grouped into four families, alpha, mu, pi, and theta, on the basis of their primary structures. In man, the pi class is represented by a single gene, GSTP1-1 (GST[pi]) localized to human chromosome 11, band q13. The oncogenes INT2, HSTF1, and PRAD1 are also localized at 11q13, and together with the GSTP1 locus and other gene loci mapped to 11q13, i.e., BCL1 and EMS1, they form a unit of DNA approximately 2000-2500 kb, known as the 11q13more » amplicon, which is often amplified in a range of solid tumors. Any gene locus at 11q13 is of interest because it may influence tumorigenesis. 14 refs., 1 fig.« less

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.

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.

The metal tolerance profile of Thlaspi goesingense is mimicked in Arabidopsis thaliana heterologously expressing serine acetyl-transferase

PubMed Central

Freeman, John L; Salt, David E

2007-01-01

Background The Ni hyperaccumulator Thlaspi goesingense is tolerant to Ni ≅ Zn, ≅ Co and slightly resistant to > Cd. We previously observed that elevated glutathione, driven by constitutive activation of serine acetyltransferase (SAT), plays a role in the Ni tolerance of T. goesingense. Results Here we show that the elevated shoot concentration of glutathione, previously shown to cause elevated Ni tolerance in Arabidopsis thaliana heterologously expressing T. goesingense mitochondrial serine acetyltransferase (SATm), also causes tolerance to Co and Zn while slightly enhancing resistance to Cd. The level of tolerance afforded to each metal is ranked Ni ≅ Co, > Zn > Cd. The Ni ≅ Co, > Zn tolerances are positively correlated with both the accumulation of glutathione (GSH) and the ability to resist the oxidative damage induced by these different metals. Based on the relative concentrations of each metal used a relatively low level of resistance to Cd was observed in both T. goesingense and TgSATm expressing lines and Cd resistance was least correlated to GSH accumulation. Conclusion Such data supports the conclusion that elevated glutathione levels, driven by constitutively enhanced SAT activity in the hyperaccumulator T. goesingense, plays an important role in the Ni, Co and Zn tolerance of this and other Thlaspi species. The hyper-activation of S assimilation through SAT is an excellent strategy for engineering enhanced metal tolerance in transgenic plants potentially used for phytoremediation. PMID:18045473

Protective effect of extract of Cordyceps sinensis in middle cerebral artery occlusion-induced focal cerebral ischemia in rats

PubMed Central

2010-01-01

Background Ischemic hypoxic brain injury often causes irreversible brain damage. The lack of effective and widely applicable pharmacological treatments for ischemic stroke patients may explain a growing interest in traditional medicines. From the point of view of "self-medication" or "preventive medicine," Cordyceps sinensis was used in the prevention of cerebral ischemia in this paper. Methods The right middle cerebral artery occlusion model was used in the study. The effects of Cordyceps sinensis (Caterpillar fungus) extract on mortality rate, neurobehavior, grip strength, lactate dehydrogenase, glutathione content, Lipid Peroxidation, glutathione peroxidase activity, glutathione reductase activity, catalase activity, Na+K+ATPase activity and glutathione S transferase activity in a rat model were studied respectively. Results Cordyceps sinensis extract significantly improved the outcome in rats after cerebral ischemia and reperfusion in terms of neurobehavioral function. At the same time, supplementation of Cordyceps sinensis extract significantly boosted the defense mechanism against cerebral ischemia by increasing antioxidants activity related to lesion pathogenesis. Restoration of the antioxidant homeostasis in the brain after reperfusion may have helped the brain recover from ischemic injury. Conclusions These experimental results suggest that complement Cordyceps sinensis extract is protective after cerebral ischemia in specific way. The administration of Cordyceps sinensis extract significantly reduced focal cerebral ischemic/reperfusion injury. The defense mechanism against cerebral ischemia was by increasing antioxidants activity related to lesion pathogenesis. PMID:20955613

GSTM1 modulation of IL-8 expression in human epithelial cells exposed to ozone

EPA Science Inventory

Exposure to the major air pollutant ozone can aggravate asthma and other lung diseases. Our recent study in humanvolunteers hasshown that the glutathione S-transferase Mu 1(GSTMI)-null genotype is associated with increased airway neutrophilic inflammation induced by inhaled ozone...

Effect of asoka on the intracellular glutathione levels and skin tumour promotion in mice.

PubMed

Varghese, C D; Nair, S C; Panikkar, B; Panikkar, K R

1993-04-15

The bark of Saraka asoca (asoka) is commonly used to treat various diseases by the Indian system of medicine and in Sri Lanka. Further purification and chemical analysis of the active compound from the bark extract of asoka showed that (-)-epicatechin was responsible for the observed antitumour/anticarcinogenic activity. Papilloma formation in mice initiated with 7,12-dimethylbenz[a]anthracene (DMBA) and promoted using croton oil was inhibited by the topical application of 100 mg/kg body weight (b.w.) of (-)-epicatechin isolated from asoka bark extract. Oral administration of the same dose restricted the growth of s.c. injected 20 methylcholanthrene (MCA) induced soil tissue fibrosarcomas significantly in mice. Elevations of almost 2-4-fold in the intracellular reduced glutathione and related enzymes viz., glutathione reductase and glutathione S-transferase of sarcoma-180 tumour cells were noted in the presence of 1 microgram/ml of (-)-epicatechin, further highlighting its antiproliferative effect.

Effects of chlorpyrifos on life cycle parameters, cytochrome P450S expression, and antioxidant systems in the monogonont rotifer Brachionus koreanus.

PubMed

Kim, Ryeo-Ok; Kim, Bo-Mi; Jeong, Chang-Bum; Lee, Jae-Seong; Rhee, Jae-Sung

2016-06-01

Chlorpyrifos is a widely used organophosphorus insecticide for controlling diverse insect pests of crops. In the monogonont rotifer Brachionus koreanus, population growth retardation with the inhibition of lifespan, fecundity, and individual body size of ovigerous females was shown over 10 d in response to chlorpyrifos exposure. At the molecular and biochemical levels, the rotifer B. koreanus defensome, composed of cytochrome P450 complements, heat shock protein 70, and antioxidant enzymatic systems (i.e., glutathione, glutathione peroxidase, glutathione reductase, and glutathione S-transferase), was significantly induced in response to different concentrations of chlorpyrifos. Thus, chlorpyrifos strongly induced a defensome system to mitigate the deleterious effects of chlorpyrifos at in vivo and in vitro levels as a trade-off in fitness costs. Environ Toxicol Chem 2016;35:1449-1457. © 2015 SETAC. © 2015 SETAC.

Protective mechanisms of Moringa oleifera against CCl(4)-induced oxidative stress in precision-cut liver slices.

PubMed

Sreelatha, S; Padma, P R

2010-01-01

The present study was designed to evaluate the efficacy of Moringa oleifera leaves against carbon tetrachloride (CCl(4))-treated liver slices in vitro. The study evaluated the antioxidant properties of Moringa oleifera leaves against CCl(4)-induced oxidative damage in liver slices. CCl(4) treatment significantly decreased the activities of antioxidant enzymes such as superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, and glutathione S-transferase and caused decreased glutathione content and increased the thiobarbituric acid-reacting substances (TBARS). Treatment with Moringa oleifera extract increased the activities of antioxidant enzymes and glutathione content and reduced the levels of TBARS significantly. Observed reduction in the level of lipid peroxides showed a decreased tendency of peroxidative damage. We conclude that, under these experimental conditions, the leaf extracts effectively suppress CCl(4)-induced oxidative stress. Our findings provide evidence to demonstrate that the possible mechanism of this activity may be due to the strong antioxidant property of the leaves. Copyright 2010 S. Karger AG, Basel.

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

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.

PABA/NO lead optimization: Improved targeting of cytotoxicity to glutathione S-transferase P1-overexpressing cancer cells.

PubMed

Kim, Youseung; Maciag, Anna E; Cao, Zhao; Deschamps, Jeffrey R; Saavedra, Joseph E; Keefer, Larry K; Holland, Ryan J

2015-08-01

PABA/NO [O(2)-{2,4-dinitro-5-[4-(N-methylamino)benzoyloxy]phenyl} 1-(N,N-dimethylamino) diazen-1-ium-1,2-diolate] is a nitric oxide (NO)-releasing arylating agent designed to be selectively activated by reaction with glutathione (GSH) on catalysis by glutathione S-transferase P1 (GSTP1), an enzyme frequently overexpressed in cancer cells. PABA/NO has proven active in several cancer models in vitro and in vivo, but its tendency to be metabolized via a variety of pathways, some that generate inactive metabolites and hydrolysis products, limits its potential as a drug. Here we show that a simple replacement of cyano for nitro at the 4 position to give compound 4b ('p-cyano-PABA/NO') has the dual effect of slowing the undesired side reactions while enhancing the proportion of NO release and arylating activity on catalysis by GSTP1. Compound 4b showed increased resistance to hydrolysis and uncatalyzed reaction with GSH, along with a more favorable product distribution in the presence of GSTP1. It also showed significant proapoptotic activity. The data suggest p-cyano-PABA/NO to be a more promising prodrug than PABA/NO, with better selectivity toward cancer cells. Published by Elsevier Ltd.

Glutathione S-transferases as antioxidant defence agents confer pyrethroid resistance in Nilaparvata lugens.

PubMed Central

Vontas, J G; Small, G J; Hemingway, J

2001-01-01

Selection of a laboratory colony of the brown planthopper Nilaparvata lugens with the pyrethroids permethrin and lambda-cyhalothrin increased its resistance to both insecticides. Biochemical analysis and synergistic studies with metabolic inhibitors indicated that elevated glutathione S-transferases (GSTs) with a predominant peroxidase activity conferred resistance to both pyrethroids, whereas esterases conferred part of the resistance to permethrin. Purified esterases hydrolysed permethrin at a slow rate, but incubation of either pyrethroid or their primary metabolites with partially purified GSTs had no effect on the metabolic profile. Although GSTs were sensitive to inhibition by both pyrethroids, they did not serve as binding proteins, as previously hypothesized [Grant and Matsumura (1988) Insect Biochem. 18, 615-622]. We demonstrate that pyrethroids, in addition to their neurotoxic effect, induce oxidative stress and lipid peroxidation in insects. Pyrethroid exposure induced lipid peroxides, protein oxidation and depleted reduced glutathione. Elevated GSTs in the resistant strains attenuated the pyrethroid-induced lipid peroxidation and reduced mortality, whereas their in vivo inhibition eliminated their protective role. We therefore hypothesize that the main role of elevated GSTs in conferring resistance in N. lugens is through protecting tissues from oxidative damage. Our study extends the GSTs' range of efficacy to pyrethroid insecticides and possibly explains the role of elevated GSTs in other pyrethroid-resistant insects. PMID:11415437

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.

Nuclear glutathione S-transferase pi prevents apoptosis by reducing the oxidative stress-induced formation of exocyclic DNA products.

PubMed

Kamada, Kensaku; Goto, Shinji; Okunaga, Tomohiro; Ihara, Yoshito; Tsuji, Kentaro; Kawai, Yoshichika; Uchida, Koji; Osawa, Toshihiko; Matsuo, Takayuki; Nagata, Izumi; Kondo, Takahito

2004-12-01

We previously found that nuclear glutathione S-transferase pi (GSTpi) accumulates in cancer cells resistant to anticancer drugs, suggesting that it has a role in the acquisition of resistance to anticancer drugs. In the present study, the effect of oxidative stress on the nuclear translocation of GSTpi and its role in the protection of DNA from damage were investigated. In human colonic cancer HCT8 cells, the hydrogen peroxide (H(2)O(2))-induced increase in nuclear condensation, the population of sub-G(1) peak, and the number of TUNEL-positive cells were observed in cells pretreated with edible mushroom lectin, an inhibitor of the nuclear transport of GSTpi. The DNA damage and the formation of lipid peroxide were dependent on the dose of H(2)O(2) and the incubation time. Immunological analysis showed that H(2)O(2) induced the nuclear accumulation of GSTpi but not of glutathione peroxidase. Formation of the 7-(2-oxo-hepyl)-substituted 1,N(2)-etheno-2'-deoxyguanosine adduct by the reaction of 13-hydroperoxyoctadecadienoic acid (13-HPODE) with 2'-deoxyguanosine was inhibited by GSTpi in the presence of glutathione. The conjugation product of 4-oxo-2-nonenal, a lipid aldehyde of 13-HPODE, with GSH in the presence of GSTpi, was identified by LS/MS. These results suggested that nuclear GSTpi prevents H(2)O(2)-induced DNA damage by scavenging the formation of lipid-peroxide-modified DNA.

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.

DEVELOPMENT OF A PEPTIDE ANTIBODY AGAINST HUMAN GLUTATHIONE S-TRANSFERASE 4-4 (HGSTA4-4) REVEALS MITOCHONDRIAL LOCALIZATION. (R827441)

EPA Science Inventory

The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

Induction of glutathione S-Transferase in Helicoverpa zea fed cashew flour.

USDA-ARS?s Scientific Manuscript database

H. zea and other insects have evolved strategies to counteract the plant protective proteins and defensive compounds they may encounter during feeding. We sought to take advantage of this phenomenon by identifying proteins upregulated in H. zea in response to the inclusion of cashew nut flour in th...

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 determinants of the intracellular concentration of 4HNE. • Higher concentrations of 4HNE promote apoptosis whereas lower promote proliferation. • Stress-mediated signaling can be modulated by the α-class glutathione S-transferase. • Genotoxic effect of 4HNE may be ameliorated by modulating the cellular GSH levels. • RLIP76 (RalBP1) mediates ATP-dependent transport of GSH-conjugate of 4HNE (GSHNE).« less

Telomere Length, Oxidative Stress, Inflammation and BDNF Levels in Siblings of Patients with Bipolar Disorder: Implications for Accelerated Cellular Aging

PubMed Central

Vasconcelos-Moreno, Mirela Paiva; Fries, Gabriel Rodrigo; Gubert, Carolina; dos Santos, Bárbara Tietböhl Martins Quadros; Fijtman, Adam; Sartori, Juliana; Ferrari, Pamela; Grun, Lucas Kich; Parisi, Mariana Migliorini; Guma, Fátima Theresinha Costa Rodrigues; Barbé-Tuana, Florencia Maria; Kapczinski, Flávio; Rosa, Adriane Ribeiro; Yatham, Lakshmi N.

2017-01-01

Abstract Background: Growing evidence supports the existence of neurobiological trait abnormalities in individuals at genetic risk for bipolar disorder. The aim of this study was to examine potential differences in brain-derived neurotrophic factor, cytokines, oxidative stress, and telomere length markers between patients with bipolar disorder, their siblings, and healthy controls. Methods: Thirty-six patients with bipolar disorder type I, 39 siblings, and 44 healthy controls were assessed. Serum levels of brain-derived neurotrophic factor, interleukin-6, interleukin-10, tumor necrosis factor-α, C-C motif chemokine 11, C-C motif chemokine 24, and 3-nitrotyrosine were measured, as were the activities of glutathione peroxidase, glutathione reductase, and glutathione S-transferase. Telomere length (T/S ratio) was measured using quantitative polymerase chain reaction. Results: Telomere length was different between the 3 groups (P = .041) with both patients and siblings showing a shorter T/S ratio compared with healthy controls. Patients showed increased levels of interleukin-6 (P = .005) and interleukin-10 (P = .002) compared with controls as well as increased levels of interleukin-6 (p = 0.014) and CCL24 (P = .016) compared with their siblings. C-C motif chemokine 11 levels were increased in siblings compared with controls (P = .015), and a similar tendency was found in patients compared with controls (P = .045). Glutathione peroxidase activity was decreased in patients compared with controls (P = .006) and siblings (P = .025). No differences were found for the other markers. Conclusions: The present results suggest that unaffected siblings may present accelerated aging features. These neurobiological findings may be considered as endophenotypic traits. Further prospective studies are warranted. PMID:28339618

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

Epigenetic alterations are involved in the overexpression of glutathione S-transferase π-1 in human colorectal cancers.

PubMed

Zhang, Rui; Kang, Kyoung Ah; Piao, Mei Jing; Kim, Ki Cheon; Zheng, Jian; Yao, Cheng Wen; Cha, Ji Won; Maeng, Young Hee; Chang, Weon Young; Moon, Pyong-Gon; Baek, Moon-Chang; Hyun, Jin Won

2014-09-01

Glutathione S-transferase π-1 (GSTP-1) is a member of the glutathione S-transferase enzyme superfamily, which catalyzes the conjugation of electrophiles to glutathione during the process of detoxification. In this study, the epigenetic alterations of GSTP-1 expression in human colorectal cancers and the underlying mechanisms were investigated. In 10 colon cancer patients, proteomic analysis revealed that expression of GSTP-1 protein was higher in tumor tissues than in paired adjacent normal tissues. Likewise, in 7 of 10 colon cancer patients, GSTP-1 protein expression was more than 1.5-fold higher in tumor tissues than in adjacent normal tissues, as determined by western blotting. Immunohistochemical data confirmed that GSTP-1 protein was expressed at higher levels in colon cancer tissues compared to normal mucosa. GSTP-1 enzyme activity was closely correlated with GSTP-1 protein expression in colon cancer patients. Consistent with this, GSTP-1 mRNA, protein and activity levels were higher in the colorectal cancer cell lines Caco-2, HCT-116, HT-29, SNU-407 and SNU-1033 compared to the normal colon cell line FHC. Methylation-specific PCR results indicated that the high levels of GSTP-1 in human colorectal cancer cell lines were likely due to the lower degree of promoter methylation in colon cancer cell lines compared to the normal colon cell line, consistent with findings in colon cancer patients. Moreover, the levels of specific activator-protein complexes and histone marks were higher in human colorectal cancer cells compared to the normal human colon cell line, whereas the repressor protein complexes exhibited the opposite pattern. Furthermore, chromatin immunoprecipitation assays demonstrated that expression levels of the transcription factors AP-1 and SP-1 were correlated with the upregulation of GSTP-1 expression in colorectal cancer cells. Finally, knockdown of GSTP-1 promoted the sensitivity of SNU-407 cells to the anticancer agent 5-fluorouracil. These data indicate that GSTP-1 may serve as a clinically useful biomarker of colon cancer and a target for anti-colon cancer drugs.

Association of mercury and selenium with altered glutathione metabolism and oxidative stress in diving ducks from the San Francisco Bay region

USGS Publications Warehouse

Hoffman, D.J.; Ohlendorf, H.M.; Marn, C.M.; Pendleton, G.W.

1998-01-01

Adult male greater scaup (Aythya marila) (GS), surf scoters (Melanitta perspicillata)(SS), and ruddy ducks (Oxyura jamaicensis) (RD) were collected from Suisun Bay and coastal Tomales Bay in the greater San Francisco Bay area to assess exposure to inorganic contaminants. Hepatic selenium (Se) concentrations were highest in GS (geometric mean = 67 ppm, dw) and SS (119 ppm) in Suisun Bay, whereas hepatic mercury (Hg) was highest (19 ppm) in GS and SS from Tomales Bay. Hepatic Se and Hg were lower in RD and did not differ between locations. Hepatic supernatants were assayed for enzymes related to glutathione metabolism and antioxidant activity including: glucose-6-phosphate dehydrogenase (G-6-PDH), glutathione peroxidase (GSH-peroxidase), glutathione reductase (GSSG-reductase), and glutathione-S-transferase (GSH-transferase). GSH-peroxidase activity was higher in SS and RD, and G-6-PDH higher in GS and SS from Suisun Bay than Tomales Bay. GSSG-reductase was higher in SS from Suisun Bay. The ratio of oxidized glutathione (GSSG) to reduced glutathione (GSH) was greater in all species from Tomales Bay. The following significant relationships were found in one or more species with increasing hepatic Hg concentration: lower body, liver and heart weights; decreased hepatic GSH concentration, G-6-PDH and GSH-peroxidase activities; increased ratio of GSSG to GSH, and increased GSSG-reductase activity. With increasing hepatic Se concentration, GSH-peroxidase increased but GSH decreased. It is concluded that measurement of associated enzymes in conjunction with thiol status may be a useful bioindicator to discriminate between Hg and Se effects. Concentrations of mercury and selenium and variable affected have been associated with adverse effects on reproduction and neurological function in experimental studies with mallards.

Chemopreventive effects of korean red ginseng extract on rat hepatocarcinogenesis.

PubMed

Kim, Hyemee; Hong, Mi-Kyung; Choi, Haymie; Moon, Hyun-Seuk; Lee, Hae-Jeung

2015-01-01

The objective of this study was to determine a chemopreventive activity of Korean red ginseng extract (KRG) in diethylnitrosamine (DEN) induced hepatocarcinogenesis in rats. After acclimatization for a week, Sprague-Dawley rats were randomized into five groups (n = 15) and fed either KRG (0.5, 1 or 2%) or control diets for 10 weeks. After two weeks of starting of experimental diets, the rats were initiated hepatocarcinogenesis by injection of DEN and were then subjected to two-thirds partial hepatectomy at five-week for developing the medium-term bioassay system. Both 0.5 and 1% KRG diets suppressed the area (55 and 60%; p= 0.0251 and 0.0144) and number (39 and 59%; p= 0.0433 and 0.0012) of glutathione S-transferase placental form (GST-P) positive foci when compared to the DEN-control group. The production of thiobarbituric acid reactive substances (TBARS) was significantly reduced in 0.5 and 1% KRG-treated rats. The supplementation of 1% KRG diet significantly elevated the levels of total glutathione (tGSH) and glutathione-related enzymes including cytosolic glutathione S-transferase (GST) and glutathione peroxidase (GPx) activities. It was also observed in cDNA microarray that the gene expressions (Cyp2c6, Cyp2e1, Cyp3a9, and Mgst1) involved in the xenobiotics metabolism via cytochrome P450 signaling pathway were down-regulated in the 1% KRG diet-treated group when compared to the DEN-control. The chemopreventive effects of KRG could be affected by 1) the decrease of lipid peroxidation, 2) the increase of tGSH content and GSH-dependent enzyme activities, and 3) the decrease of the gene expression profile involved in cytochrome P450 signaling pathway. These results suggest that KRG may prove to be a therapeutic agent against hepatocarcinogenesis.

Chemopreventive Effects of Korean Red Ginseng Extract on Rat Hepatocarcinogenesis

PubMed Central

Kim, Hyemee; Hong, Mi-Kyung; Choi, Haymie; Moon, Hyun-Seuk; Lee, Hae-Jeung

2015-01-01

The objective of this study was to determine a chemopreventive activity of Korean red ginseng extract (KRG) in diethylnitrosamine (DEN) induced hepatocarcinogenesis in rats. After acclimatization for a week, Sprague-Dawley rats were randomized into five groups (n = 15) and fed either KRG (0.5, 1 or 2%) or control diets for 10 weeks. After two weeks of starting of experimental diets, the rats were initiated hepatocarcinogenesis by injection of DEN and were then subjected to two-thirds partial hepatectomy at five-week for developing the medium-term bioassay system. Both 0.5 and 1% KRG diets suppressed the area (55 and 60%; p= 0.0251 and 0.0144) and number (39 and 59%; p= 0.0433 and 0.0012) of glutathione S-transferase placental form (GST-P) positive foci when compared to the DEN-control group. The production of thiobarbituric acid reactive substances (TBARS) was significantly reduced in 0.5 and 1% KRG-treated rats. The supplementation of 1% KRG diet significantly elevated the levels of total glutathione (tGSH) and glutathione-related enzymes including cytosolic glutathione S-transferase (GST) and glutathione peroxidase (GPx) activities. It was also observed in cDNA microarray that the gene expressions (Cyp2c6, Cyp2e1, Cyp3a9, and Mgst1) involved in the xenobiotics metabolism via cytochrome P450 signaling pathway were down-regulated in the 1% KRG diet-treated group when compared to the DEN-control. The chemopreventive effects of KRG could be affected by 1) the decrease of lipid peroxidation, 2) the increase of tGSH content and GSH-dependent enzyme activities, and 3) the decrease of the gene expression profile involved in cytochrome P450 signaling pathway. These results suggest that KRG may prove to be a therapeutic agent against hepatocarcinogenesis. PMID:25553083

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

Arabidopsis GLUTATHIONE REDUCTASE1 Plays a Crucial Role in Leaf Responses to Intracellular Hydrogen Peroxide and in Ensuring Appropriate Gene Expression through Both Salicylic Acid and Jasmonic Acid Signaling Pathways1[C][W][OA

PubMed Central

Mhamdi, Amna; Hager, Jutta; Chaouch, Sejir; Queval, Guillaume; Han, Yi; Taconnat, Ludivine; Saindrenan, Patrick; Gouia, Houda; Issakidis-Bourguet, Emmanuelle; Renou, Jean-Pierre; Noctor, Graham

2010-01-01

Glutathione is a major cellular thiol that is maintained in the reduced state by glutathione reductase (GR), which is encoded by two genes in Arabidopsis (Arabidopsis thaliana; GR1 and GR2). This study addressed the role of GR1 in hydrogen peroxide (H2O2) responses through a combined genetic, transcriptomic, and redox profiling approach. To identify the potential role of changes in glutathione status in H2O2 signaling, gr1 mutants, which show a constitutive increase in oxidized glutathione (GSSG), were compared with a catalase-deficient background (cat2), in which GSSG accumulation is conditionally driven by H2O2. Parallel transcriptomics analysis of gr1 and cat2 identified overlapping gene expression profiles that in both lines were dependent on growth daylength. Overlapping genes included phytohormone-associated genes, in particular implicating glutathione oxidation state in the regulation of jasmonic acid signaling. Direct analysis of H2O2-glutathione interactions in cat2 gr1 double mutants established that GR1-dependent glutathione status is required for multiple responses to increased H2O2 availability, including limitation of lesion formation, accumulation of salicylic acid, induction of pathogenesis-related genes, and signaling through jasmonic acid pathways. Modulation of these responses in cat2 gr1 was linked to dramatic GSSG accumulation and modified expression of specific glutaredoxins and glutathione S-transferases, but there is little or no evidence of generalized oxidative stress or changes in thioredoxin-associated gene expression. We conclude that GR1 plays a crucial role in daylength-dependent redox signaling and that this function cannot be replaced by the second Arabidopsis GR gene or by thiol systems such as the thioredoxin system. PMID:20488891

Arabidopsis GLUTATHIONE REDUCTASE1 plays a crucial role in leaf responses to intracellular hydrogen peroxide and in ensuring appropriate gene expression through both salicylic acid and jasmonic acid signaling pathways.

PubMed

Mhamdi, Amna; Hager, Jutta; Chaouch, Sejir; Queval, Guillaume; Han, Yi; Taconnat, Ludivine; Saindrenan, Patrick; Gouia, Houda; Issakidis-Bourguet, Emmanuelle; Renou, Jean-Pierre; Noctor, Graham

2010-07-01

Glutathione is a major cellular thiol that is maintained in the reduced state by glutathione reductase (GR), which is encoded by two genes in Arabidopsis (Arabidopsis thaliana; GR1 and GR2). This study addressed the role of GR1 in hydrogen peroxide (H(2)O(2)) responses through a combined genetic, transcriptomic, and redox profiling approach. To identify the potential role of changes in glutathione status in H(2)O(2) signaling, gr1 mutants, which show a constitutive increase in oxidized glutathione (GSSG), were compared with a catalase-deficient background (cat2), in which GSSG accumulation is conditionally driven by H(2)O(2). Parallel transcriptomics analysis of gr1 and cat2 identified overlapping gene expression profiles that in both lines were dependent on growth daylength. Overlapping genes included phytohormone-associated genes, in particular implicating glutathione oxidation state in the regulation of jasmonic acid signaling. Direct analysis of H(2)O(2)-glutathione interactions in cat2 gr1 double mutants established that GR1-dependent glutathione status is required for multiple responses to increased H(2)O(2) availability, including limitation of lesion formation, accumulation of salicylic acid, induction of pathogenesis-related genes, and signaling through jasmonic acid pathways. Modulation of these responses in cat2 gr1 was linked to dramatic GSSG accumulation and modified expression of specific glutaredoxins and glutathione S-transferases, but there is little or no evidence of generalized oxidative stress or changes in thioredoxin-associated gene expression. We conclude that GR1 plays a crucial role in daylength-dependent redox signaling and that this function cannot be replaced by the second Arabidopsis GR gene or by thiol systems such as the thioredoxin system.

Seasonal dynamics of biomarkers in infaunal clam Macoma balthica from the Gulf of Riga (Baltic Sea)

NASA Astrophysics Data System (ADS)

Barda, Ieva; Purina, Ingrida; Rimsa, Elina; Balode, Maija

2014-01-01

Biomarkers are often regarded as “early warning” signals of environmental pollution; however seasonal changes are mentioned as one of the most important factor that influences the activity of biomarkers. The aim of our study was to assess the importance of seasonal variation of selected contaminant biomarkers in Macoma balthica to provide background information for further environmental surveys in the Gulf of Riga. Seasonal variation of biomarkers (acetylcholinesterase (AChE), catalase (CAT), glutathione reductase (GR) and glutathione-S-transferase (GST)) was measured in infaunal clam M. balthica from the southern part of the Gulf of Riga. The majority of biomarkers (GST, CAT and GR) showed strong seasonal variability; however only CAT and GR were found to be significantly related to environmental factors (near-bottom oxygen, salinity and temperature). Integrated biomarker response (IBR) index indicated that the most stressed condition of M. balthica is during August and May. The highest values of IBR were found near the mouth of the River Daugava, suggesting the impact of environmental pollution on the benthic animals.

Glutathione protects Candida albicans against horseradish volatile oil.

PubMed

Bertóti, Regina; Vasas, Gábor; Gonda, Sándor; Nguyen, Nhat Minh; Szőke, Éva; Jakab, Ágnes; Pócsi, István; Emri, Tamás

2016-10-01

Horseradish essential oil (HREO; a natural mixture of different isothiocyanates) had strong fungicide effect against Candida albicans both in volatile and liquid phase. In liquid phase this antifungal effect was more significant than those of its main components allyl, and 2-phenylethyl isothiocyanate. HREO, at sublethal concentration, induced oxidative stress which was characterized with elevated superoxide content and up-regulated specific glutathione reductase, glutathione peroxidase, catalase and superoxide dismutase activities. Induction of specific glutathione S-transferase activities as marker of glutathione (GSH) dependent detoxification was also observed. At higher concentration, HREO depleted the GSH pool, increased heavily the superoxide production and killed the cells rapidly. HREO and the GSH pool depleting agent, 1-chlore-2,4-dinitrobenzene showed strong synergism when they were applied together to kill C. albicans cells. Based on all these, we assume that GSH metabolism protects fungi against isothiocyanates. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

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

Landscape and pesticide effects on honey bees: forager survival and expression of acetylcholinesterase and brain oxidative genes

USDA-ARS?s Scientific Manuscript database

The aim of the present work was to assess the effects of agricultural pesticides on honey bee (Apis mellifera L.) survival and physiological stress. Integrated use of acetylcholinesterase (AChE) and antioxidant enzymes (catalase and glutathione S-transferase) was tested on honey bee brains for detec...

Variation of acephate susceptibility and correlation with Esterase and Glutathione S-transferase activities in field populations of the tarnished plant bug, Lygus lineolaris

USDA-ARS?s Scientific Manuscript database

The tarnished plant bug (TPB) has increasingly become an economically important pest of cotton. Heavy dependence on insecticides, particularly organophosphates and pyrethroids, for TPB control facilitated resistance development to multiple classes of insecticides. To better understand resistance and...

Multivariate analysis of maize disease resistances suggests a pleiotropic genetic basis and implicates a glutathione S-transferase gene

USDA-ARS?s Scientific Manuscript database

Plants are attacked by pathogens representing diverse taxonomic groups, such that genes providing multiple disease resistance (MDR) would likely be under positive selection pressure. We examined the novel proposition that naturally occurring allelic variants may confer MDR. To do so, we applied a ...

Dual Lifetimes for Complexes between Glutathione-S-transferase (hGSTA1-1) and Product-like Ligands Detected by Single-Molecule Fluorescence Imaging.

PubMed

Pettersson, John R; Lanni, Frederick; Rule, Gordon S

2017-08-08

Single-molecule fluorescence techniques were used to characterize the binding of products and inhibitors to human glutathione S-transferase A1-1 (hGSTA1-1). The identification of at least two different bound states for the wild-type enzyme suggests that there are at least two conformations of the protein, consistent with the model that ligand binding promotes closure of the carboxy-terminal helix over the active site. Ligand induced changes in ensemble fluorescence energy transfer support this proposed structural change. The more predominant state in the ensemble of single molecules shows a significantly faster off-rate, suggesting that the carboxy-terminal helix is delocalized in this state, permitting faster exit of the bound ligand. A point mutation (I219A), which is known to interfere with the association of the carboxy-terminal helix with the enzyme, shows increased rates of interconversion between the open and closed state. Kinematic traces of fluorescence from single molecules show that a single molecule readily samples a number of different conformations, each with a characteristic off-rate.

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.

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.

Glutathione S-transferase gene polymorphisms (GSTM1, GSTT1, and GSTP1) in Egyptian pediatric patients with sickle cell disease.

PubMed

Shiba, Hala Fathy; El-Ghamrawy, Mona Kamal; Shaheen, Iman Abd El-Mohsen; Ali, Rasha Abd El-Ghani; Mousa, Somaia Mohammed

2014-01-01

Sickle cell disease (SCD) complications are associated with oxidative stress. Glutathione S-transferases (GSTs) are a group of enzymes that protect against oxidative stress. The aims of this study was to evaluate the prevalence of GSTM1, GSTT1, and GSTP1 gene polymorphisms among homozygous sickle cell anemia patients and to investigate the possible association between the presence of these polymorphisms and SCD severity and complications. Genotyping the polymorphisms in GSTT1 and GSTM1 genes was performed using the multiplex polymerase chain reaction (PCR) method. The GSTP1 ILe105Val polymorphism was determined using PCR-restriction fragment length polymorphism. GSTM1 null genotype was significantly associated with increased risk of severe vaso-occlusive crises (VOC) (odds ratio  =  1.52, 95% confidence interval  =  0.42-5.56, P  =  0.005). We found no significant association between GST genotypes and frequency of sickle cell-related pain, transfusion frequency, disease severity, or hydroxyurea treatment. GSTM1 gene polymorphism may be associated with risk of severe VOC among Egyptian SCD patients.

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

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.

Effects of oxytetracycline and amoxicillin on development and biomarkers activities of zebrafish (Danio rerio).

PubMed

Oliveira, Rhaul; McDonough, Sakchai; Ladewig, Jessica C L; Soares, Amadeu M V M; Nogueira, António J A; Domingues, Inês

2013-11-01

Antibiotics have been widely used in human and veterinary medicine to treat or prevent diseases. Residues of antibiotics have been found in aquatic environments, but their effects on fish have been not properly investigated. This work aimed to assess the sub-lethal effects of oxytetracycline and amoxicillin on zebrafish development and biomarkers. Embryos and adults were exposed during 96 h to amoxicillin and oxytetracycline following OECD guidelines. Tissues of adults and pools of embryos were used for catalase, glutathione-S-transferases and lactate dehydrogenase determinations. Amoxicillin caused premature hatching (48 h-EC50=132.4 mg/l) whereas oxytetracycline cause delayed hatching of embryos (72 h-EC50=127.6 mg/l). Moreover, both antibiotics inhibited catalase and induced glutathione-S-transferases in zebrafish adults. However, only oxytetracycline induced lactate dehydrogenase. Short-term effects of antibiotics were observed at high doses (mg/l) indicating that physiological impairment in fish populations is unlike to occur. However, effects of chronic exposures to low doses of ABs must be investigated. Copyright © 2013 Elsevier B.V. All rights reserved.

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.

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.

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

Relation between glutathione S-transferase genes (GSTM1, GSTT1, and GSTP1) polymorphisms and clinical manifestations of sickle cell disease in Egyptian patients.

PubMed

Ellithy, Hend N; Yousri, Sherif; Shahin, Gehan H

2015-12-01

Clinical manifestations of sickle cell disease (SCD) result from sickling of Hb S due to oxidation, which is augmented by accumulation of oxygen-free radicals. Deficiencies in normal antioxidant protective mechanism might lead to clinical manifestations of SCD like vaso-occlusive crisis (VOC) and acute chest syndrome (ACS). The glutathione system plays an important role in the removal of endogenous products of peroxidation of lipids, thus protecting cells and tissue against damage from oxidative stress. Impairment of the glutathione system due to genetic polymorphisms of glutathione S-transferase (GST) genes is expected to increase the severity of SCD manifestations. This report describes a case control study aimed at studying the ethnic-dependent variation in the frequency of GST gene polymorphisms among participants selected from the Egyptian population and to find out the association between GST gene polymorphisms and the severity of SCD manifestations. We measured the frequency distribution of the three GSTs gene polymorphisms in 100 Egyptian adult SCD patients and 80 corresponding controls. GSTM1 and GSTT1 genotypes were determined by multiplex polymerase chain reaction (PCR). GSTP1 genotyping was conducted with a PCR-restriction fragment length polymorphism assay. The GSTM1 null genotype was significantly associated with ACS and VOC (P = 0.03 and 0.01, respectively). The GSTT1 null genotype was associated with significantly increased requirement of blood transfusion (P = 0.01). Absence of both GSTM1 and GSTT1 genes was significantly associated with pulmonary hypertension (P = 0.04). The non-wild-type GSTP1 polymorphism was not associated with clinical manifestations of SCD. Some GST gene polymorphisms were significantly associated with the worsening of the clinical manifestations of SCD.

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 versatile role of GST genes in crop engineering. PMID:29095889

Modulatory effect of Scoparia dulcis in oxidative stress-induced lipid peroxidation in streptozotocin diabetic rats.

PubMed

Latha, M; Pari, L

2003-01-01

In light of evidence that diabetes mellitus is associated with oxidative stress and altered antioxidant status, we investigated the effect of Scoparia dulcis plant extracts (SPEt) (aqueous, ethanolic, and chloroform) in streptozotocin diabetic rats. Significant increases in the activities of insulin, superoxide dismutase, catalase, glutathione peroxidase, glutathione-S-transferase, reduced glutathione, vitamin C, and vitamin E were observed in liver, kidney, and brain on treatment with SPEt. In addition, the treated groups also showed significant decreases in blood glucose, thiobarbituric acid-reactive substances, and hydroperoxide formation in tissues, suggesting its role in protection against lipid peroxidation-induced membrane damage. Thus, the results of the present study indicate that extracts of S. dulcis, especially the aqueous extract, showed a modulatory effect by attenuating the above lipid peroxidation in streptozotocin diabetes.

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.

Impacts on silkworm larvae midgut proteomics by transgenic Trichoderma strain and analysis of glutathione S-transferase sigma 2 gene essential for anti-stress response of silkworm larvae.

PubMed

Li, Yingying; Dou, Kai; Gao, Shigang; Sun, Jianan; Wang, Meng; Fu, Kehe; Yu, Chuanjin; Wu, Qiong; Li, Yaqian; Chen, Jie

2015-08-03

Lepidoptera is a large order of insects that have major impacts on humans as agriculture pests. The midgut is considered an important target for insect control. In the present study, 10 up-regulated, 18 down-regulated, and one newly emerged protein were identified in the transgenic Trichoderma-treated midgut proteome. Proteins related to stress response, biosynthetic process, and metabolism process were further characterized through quantitative real-time PCR (qPCR). Of all the identified proteins, the glutathione S-transferase sigma 2 (GSTs2) gene displayed enhanced expression when larvae were fed with Trichoderma wild-type or transgenic strains. Down regulation of GSTs2 expression by RNA interference (RNAi) resulted in inhibition of silkworm growth when larvae were fed with mulberry leaves treated with the transgenic Trichoderma strain. Weight per larva decreased by 18.2%, 11.9%, and 10.7% in the untreated control, ddH2O, and GFP dsRNA groups, respectively, at 24h, while the weight decrease was higher at 42.4%, 28.8% and 32.4% at 72 h after treatment. Expression of glutathione S-transferase omega 2 (GSTo2) was also enhanced when larvae were fed with mulberry leaves treated with the transgenic Trichoderma strain. These results indicated that there was indeed correlation between enhanced expression of GSTs2 and the anti-stress response of silkworm larvae against Trichoderma. This study represents the first attempt at understanding the effects of transgenic organisms on the midgut proteomic changes in silkworm larvae. Our findings could not only broaden the biological control targets of insect at the molecular level, but also provide a theoretical foundation for biological safety evaluation of the transgenic Trichoderma strain. Copyright © 2015 Elsevier B.V. All rights reserved.

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.

Hepatoprotective potential of ethanolic extract of Ziziphus oenoplia (L.) Mill roots against antitubercular drugs induced hepatotoxicity in experimental models.

PubMed

Rao, Ch V; Rawat, A K S; Singh, Anil P; Singh, Arpita; Verma, Neeraj

2012-04-01

To evaluate the hepatoprotective potential of ethanolic (50%) extract of Ziziphus oenoplia (L.) Mill (Z. oenoplia) root against isoniazid (INH) and rifampicin (RIF) induced liver damage in animal models. Five groups of six rats each were selected for the study. Ethanolic extract at a dose of 150 and 300 mg/kg as well as silymarin (100 mg/kg) were administered orally once daily for 21 d in INH + RIF treated groups. The serum levels of glutamic oxaloacetic transaminase (SGOT), glutamate pyruvate transaminase (SGPT), alkaline phosphatase (SALP), and bilirubin were estimated along with activities of superoxide dismutase, catalase, glutathione S-transferase, glutathione peroxidase, and hepatic melondialdehyde formation. Histopathological analysis was carried out to assess injury to the liver. The considerably elevated serum enzymatic activities of glutamic oxaloacetic transaminase, glutamate pyruvate transaminase, alkaline phosphatase and bilirubin due to INH + RIF treatment were restored towards normal in a dose dependent manner after the treatment with ethanolic extract of Z. oenoplia roots. Meanwhile, the decreased activities of superoxide dismutase, catalase, glutathione S-transferase and glutathione peroxidase were also restored towards normal dose dependently. In addition, ethanolic extract also significantly prevented the elevation of hepatic melondialdehyde formation in the liver of INH + RIF intoxicated rats in a dose dependent manner. The biochemical observations were supplemented with histopathological examination of rat liver sections. The results of this study strongly indicate that ethanolic extract of Z. oenoplia has a potent hepatoprotective action against INH + RIF induced hepatic damage in rats. Copyright © 2012 Hainan Medical College. Published by Elsevier B.V. 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, 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.

The neuronal differentiation process involves a series of antioxidant proteins.

PubMed

Oh, J-E; Karlmark Raja, K; Shin, J-H; Hengstschläger, M; Pollak, A; Lubec, G

2005-11-01

Involvement of individual antioxidant proteins (AOXP) and antioxidants in the differentiation process has been already reported. A systematic search strategy for detecting differentially regulated AOXP in neuronal differentiation, however, has not been published so far. The aim of this study was to provide an analytical tool identifying AOXP and to generate a differentiation-related AOXP expressional pattern. The undifferentiated N1E-115 neuroblastoma cell line was switched into a neuronal phenotype by DMSO treatment and used for proteomic experiments: We used two-dimensional gel electrophoresis followed by unambiguous mass spectrometrical (MALDI-TOF-TOF) identification of proteins to generate a map of AOXP. 16 AOXP were unambiguously determined in both cell lines; catalase, thioredoxin domain-containing protein 4 and hypothetical glutaredoxin/glutathione S-transferase C terminus-containing protein were detectable in the undifferentiated cells only. Five AOXP were observed in both, undifferentiated and differentiated cells and thioredoxin, thioredoxin-like protein p19, thioredoxin reductase 1, superoxide dismutases (Mn and Cu-Zn), glutathione synthetase, glutathione S-transferase P1 and Mu1 were detected in differentiated cells exclusively. Herein a differential expressional pattern is presented that reveals so far unpublished antioxidant principles involved in neuronal differentiation by a protein chemical approach, unambiguously identifying AOXP. This finding not only shows concomitant determination of AOXP but also serves as an analytical tool and forms the basis for design of future studies addressing AOXP and differentiation per se.

A Glutathione S-Transferase Catalyzes the Dehalogenation of Inhibitory Metabolites of Polychlorinated Biphenyls

PubMed Central

Fortin, Pascal D.; Horsman, Geoff P.; Yang, Hao M.; Eltis, Lindsay D.

2006-01-01

BphK is a glutathione S-transferase of unclear physiological function that occurs in some bacterial biphenyl catabolic (bph) pathways. We demonstrated that BphK of Burkholderia xenovorans strain LB400 catalyzes the dehalogenation of 3-chloro 2-hydroxy-6-oxo-6-phenyl-2,4-dienoates (HOPDAs), compounds that are produced by the cometabolism of polychlorinated biphenyls (PCBs) by the bph pathway and that inhibit the pathway's hydrolase. A one-column protocol was developed to purify heterologously produced BphK. The purified enzyme had the greatest specificity for 3-Cl HOPDA (kcat/Km, ∼104 M−1 s−1), which it dechlorinated approximately 3 orders of magnitude more efficiently than 4-chlorobenzoate, a previously proposed substrate of BphK. The enzyme also catalyzed the dechlorination of 5-Cl HOPDA and 3,9,11-triCl HOPDA. By contrast, BphK did not detectably transform HOPDA, 4-Cl HOPDA, or chlorinated 2,3-dihydroxybiphenyls. The BphK-catalyzed dehalogenation proceeded via a ternary-complex mechanism and consumed 2 equivalents of glutathione (GSH) (Km for GSH in the presence of 3-Cl HOPDA, ∼0.1 mM). A reaction mechanism consistent with the enzyme's specificity is proposed. The ability of BphK to dehalogenate inhibitory PCB metabolites supports the hypothesis that this enzyme was recruited to facilitate PCB degradation by the bph pathway. PMID:16740949

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

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.

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.

JS-K, a glutathione/glutathione S-transferase-activated nitric oxide releasing prodrug inhibits androgen receptor and WNT-signaling in prostate cancer cells

PubMed Central

2012-01-01

Background Nitric oxide (NO) and its oxidative reaction products have been repeatedly shown to block steroid receptor function via nitrosation of zinc finger structures in the DNA-binding domain (DBD). In consequence NO-donors could be of special interest for the treatment of deregulated androgen receptor(AR)-signaling in castration resistant prostate cancer (CRPC). Methods Prostate cancer (PCa) cells were treated with JS-K, a diazeniumdiolate derivate capable of generating large amounts of intracellular NO following activation by glutathione S-transferase. Generation of NO was determined indirectly by the detection of nitrate in tissue culture medium or by immunodetection of nitrotyrosine in the cytoplasm. Effects of JS-K on intracellular AR-levels were determined by western blotting. AR-dimerization was analyzed by mammalian two hybrid assay, nuclear translocation of the AR was visualized in PCa cells transfected with a green fluorescent AR-Eos fusion protein using fluorescence microscopy. Modulation of AR- and WNT-signalling by JS-K was investigated using reporter gene assays. Tumor cell proliferation following JS-K treatment was measured by MTT-Assay. Results The NO-releasing compound JS-K was shown to inhibit AR-mediated reporter gene activity in 22Rv1 CRPC cells. Inhibition of AR signaling was neither due to an inhibition of nuclear import nor to a reduction in AR-dimerization. In contrast to previously tested NO-donors, JS-K was able to reduce the intracellular concentration of functional AR. This could be attributed to the generation of extremely high intracellular levels of the free radical NO as demonstrated indirectly by high levels of nitrotyrosine in JS-K treated cells. Moreover, JS-K diminished WNT-signaling in AR-positive 22Rv1 cells. In line with these observations, castration resistant 22Rv1 cells were found to be more susceptible to the growth inhibitory effects of JS-K than the androgen dependent LNCaP which do not exhibit an active WNT-signaling pathway. Conclusions Our results suggest that small molecules able to inhibit WNT- and AR-signaling via NO-release represent a promising platform for the development of new compounds for the treatment of CRPC. PMID:22462810

Structural and functional analysis of an enhancer GPEI having a phorbol 12-O-tetradecanoate 13-acetate responsive element-like sequence found in the rat glutathione transferase P gene.

PubMed

Okuda, A; Imagawa, M; Maeda, Y; Sakai, M; Muramatsu, M

1989-10-05

We have recently identified a typical enhancer, termed GPEI, located about 2.5 kilobases upstream from the transcription initiation site of the rat glutathione transferase P gene. Analyses of 5' and 3' deletion mutants revealed that the cis-acting sequence of GPEI contained the phorbol 12-O-tetradecanoate 13-acetate responsive element (TRE)-like sequence in it. For the maximal activity, however, GPEI required an adjacent upstream sequence of about 19 base pairs in addition to the TRE-like sequence. With the DNA binding gel-shift assay, we could detect protein(s) that specifically binds to the TRE-like sequence of GPEI fragment, which was possibly c-jun.c-fos complex or a similar protein complex. The sequence immediately upstream of the TRE-like sequence did not have any activity by itself, but augmented the latter activity by about 5-fold.

Demonstration of nuclear compartmentalization of glutathione in hepatocytes.

PubMed Central

Bellomo, G; Vairetti, M; Stivala, L; Mirabelli, F; Richelmi, P; Orrenius, S

1992-01-01

The intracellular distribution of glutathione (GSH) in cultured hepatocytes has been investigated by using the compound monochlorobimane (BmCl), which interacts specifically with GSH to form a highly fluorescent adduct. Image analysis of BmCl-labeled hepatocytes predominantly localized the fluorescence in the nucleus; the nuclear/cytoplasmic concentration gradient was approximately three. This concentration gradient was collapsed by treatment of the cells with ATP-depleting agents. The uneven distribution of BmCl fluorescence was not attributable to (i) nonspecific interaction of BmCl with protein sulfhydryl groups, (ii) any selective nuclear localization of the GSH transferase(s) catalyzing formation of the GSH-BmCl conjugate, or (iii) any apparent alterations in cell morphology from culture conditions, suggesting that this distribution did, indeed, reflect a nuclear compartmentalization of GSH. That the nuclear pool of GSH was found more resistant to depletion by several agents than the cytoplasmic pool supports the assumption that GSH is essential in protecting DNA and other nuclear structures from chemical injury. Images PMID:1584774

DICHLOROACETATE TOXICOKINETICS AND DISRUPTION OF TYROSINE CATABOLISM IN B6C3F1 MICE: DOSE RESPONSE RELATIONSHIPS AND AGE AS A MODIFYING FACTOR. (R825954)

EPA Science Inventory

Dichloroacetate (DCA) is a rodent carcinogen commonly found in municipal drinking water supplies. Toxicokinetic studies have established that elimination of DCA is controlled by liver metabolism, which occurs by the cytosolic enzyme glutathione-S-transferase-zeta (GST-z...

Mapping insecticide resistance and characterization of resistance mechanisms in Anopheles arabiensis (Diptera: Culicidae) in Ethiopia.

PubMed

Alemayehu, Eba; Asale, Abebe; Eba, Kasahun; Getahun, Kefelegn; Tushune, Kora; Bryon, Astrid; Morou, Evangelia; Vontas, John; Van Leeuwen, Thomas; Duchateau, Luc; Yewhalaw, Delenasaw

2017-09-02

The emergence and spread of insecticide resistance in the major African malaria vectors Anopheles gambiae (s.s.) and An. arabiensis may compromise the current vector control interventions and threatens the global malaria control and elimination efforts. Insecticide resistance was monitored in several study sites in Ethiopia from 2013 to 2015 using papers impregnated with discriminating concentrations of DDT, deltamethrin, bendiocarb, propoxur, malathion, fenitrothion and pirimiphos-methyl, following the WHO insecticide susceptibility test procedure. Mosquitoes sampled from different localities for WHO bioassay were morphologically identified as An. gambiae (s.l.) using standard taxonomic keys. Samples were identified to species using species-specific polymerase chain reaction (PCR) and screened for the presence of target site mutations L1014F, L1014S and N1575Y in the voltage gated sodium channel (VGSC) gene and G119S in the acethylcholinesterase (AChE) gene using allele-specific PCR. Biochemical assays were performed to assess elevated levels of acetylcholinesterases, carboxylcholinesterases, glutathione-S-transferases (GSTs) and cytochrome P450s monooxygenases in wild populations of An. arabiensis, compared to the fully susceptible Sekoru An. arabiensis laboratory strain. Populations of An. arabiensis were resistant to DDT and deltamethrin but were susceptible to fenitrothion in all the study sites. Reduced susceptibility to malathion, pirimiphos-methyl, propoxur and bendiocarb was observed in some of the study sites. Knockdown resistance (kdr L1014F) was detected in all mosquito populations with allele frequency ranging from 42 to 91%. Elevated levels of glutathione-S-transferases (GSTs) were detected in some of the mosquito populations. However, no elevated levels of monooxygenases and esterases were detected in any of the populations assessed. Anopheles arabiensis populations from all surveyed sites in Ethiopia exhibited resistance against DDT and pyrethroids. Moreover, some mosquito populations exhibited resistance to propoxur and possible resistance to bendiocarb. Target site mutation kdr L1014F was detected in all mosquito populations while elevated levels of glutathione-S-transferases (GSTs) was detected in some mosquito populations. The reduced susceptibility of An. arabiensis to propoxur and bendiocarb, which are currently used for indoor residual spraying (IRS) in Ethiopia, calls for continuous resistance monitoring, in order to plan and implement evidence based insecticide resistance management.

3-Nitrotyrosine and glutathione antioxidant system in patients in the early and late stages of bipolar disorder

PubMed Central

Andreazza, Ana Cristina; Kapczinski, Flavio; Kauer-Sant’Anna, Marcia; Walz, Julio C.; Bond, David J.; Gonçalves, Carlos A.; Young, L. Trevor; Yatham, Lakshmi N.

2009-01-01

Background There has been an increasing interest in the role of oxidative stress in the pathophysiology of bipolar disorder. To explore this further, we evaluated the activity of glutathione peroxidase (GPx), glutathione reductase (GR) and glutathione S-transferase (GST), as well as 3-nitrotyrosine levels and carbonyl content in patients in the early (within 3 years of illness onset) and late (a minimum of 10 years of illness) stages of bipolar disorder. Methods We matched 30 patients in the early stage and 30 patients in the late stage of bipolar disorder, diagnosed according to DSM-IV criteria, with 60 healthy controls (30 matched for each group of patients). We measured symptomatic status using the Hamilton Rating Scale for Depression and the Young Mania Rating Scale. Results We found a significant increase in 3-nitrotyrosine levels among patients in the early (p < 0.010) and late (p < 0.010) stages of bipolar disorder. The activity of GR and GST was increased only among patients in the late stage of illness. Glutathione peroxidase activity and carbonyl content did not differ among the groups. Limitations Limitations of our study include its cross-sectional design, which did not allow us to examine direct causative mechanisms or the effects of progression of illness, and the potential environmental bias introduced by comparing patient groups recruited from different regions of the world. Conclusion Our data indicate a possible tyrosine nitration-induced damage in patients with bipolar disorder that is present from the early stage of illness. Our data also indicate that patients in the late stage of illness demonstrate enhanced activity of GR and GST, which could suggest the involvement of a compensatory system in bipolar disorder. PMID:19568477

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

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.

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.

Protective effect of Corchorus olitorius leaves against arsenic-induced oxidative stress in rat brain.

PubMed

Das, Anup K; Dewanjee, Saikat; Sahu, Ranabir; Dua, Tarun K; Gangopadhyay, Moumita; Sinha, Mohit K

2010-01-01

The present study was undertaken to evaluate the protective effect of an aqueous extract of Corchorus olitorius leaves (AECO) against NaAsO(2) induced brain toxicity in experimental rats. The animals exposed to NaAsO(2) (10mg/kg, p.o.) for 10 days exhibited a significant inhibition (p<0.01) of superoxide dismutase, catalase, glutathione-S-transferase, glutathione peroxidase, glutathione reductase and reduced glutathione levels in rat brain. In addition, the toxin increased (p<0.01) the levels of oxidized glutathione and thiobarbituric acid reactive substances in the brain tissue of experimental rats. Treatment with AECO (50 and 100mg/kg, p.o.) for 15 days prior to arsenic intoxication significantly improved antioxidant markers in a dose dependant manner. Histological studies on the ultrastructural changes of brain tissue supported the protective activity of the AECO. The results suggest that treatment with AECO prior to arsenic intoxication has a significant role in protecting animals from arsenic-induced toxicity. Copyright © 2009 Elsevier B.V. All rights reserved.

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.

Ethacrynic acid and a derivative enhance apoptosis in arsenic trioxide-treated myeloid leukemia and lymphoma cells: the role of glutathione S-transferase P1-1

PubMed Central

Wang, Rui; Liu, Changda; Xia, Lijuan; Zhao, Guisen; Gabrilove, Janice; Waxman, Samuel; Jing, Yongkui

2012-01-01

Purpose Arsenic trioxide (ATO) as a single agent is used for treatment of acute promyelocytic leukemia (APL) with minimal toxicity but therapeutic effect of ATO in other types of malignancies has not been achieved. We tested whether a combination with ethacrynic acid (EA), a glutathione S-transferase P1-1 (GSTP1-1) inhibitor and a reactive oxygen species (ROS) inducer will extend the therapeutic effect of ATO beyond APL. Experimental Design The combined apoptotic effects of ATO plus EA were tested in non-APL leukemia and lymphoma cell lines. The role of ROS, GSTP1-1, glutathione, and Mcl-1 in apoptosis was determined. The selective response to this combination of cells with and without GSTP1-1 expression was compared. Results ATO/EA combination synergistically induced apoptosis in myeloid leukemia and lymphoma cells. This treatment produced high ROS levels, activated c-jun-NH2-terminal kinase and reduced Mcl-1 protein. This led to the decrease of mitochondrial transmembrane potential, release of cytochrome c and, subsequently, to activation of caspase 3 and 9. Induction of apoptosis in leukemia and lymphoma cells expressing GSTP1-1 required that high EA concentrations be combined with ATO. Silencing of GSTP1 in leukemia cells sensitized them to ATO/EA-induced apoptosis. In a sub-group of B-cell lymphoma which do not express GSTP1-1, lower concentrations of EA and its more potent derivative, ethacrynic acid butyl-ester, decreased intracellular glutathione levels and synergistically induced apoptosis when combined with ATO. Conclusion B-cell lymphoma cells lacking GSTP1-1 are more sensitive than myeloid leukemia cells to ATO/EA-induced apoptosis. PMID:23082001

High-Throughput Library Screening Identifies Two Novel NQO1 Inducers in Human Lung Cells

PubMed Central

Marquardt, Gaby; Massimi, Aldo B.; Shi, Miao; Han, Weiguo; Spivack, Simon D.

2012-01-01

Many phytochemicals possess antioxidant and cancer-preventive properties, some putatively through antioxidant response element–mediated phase II metabolism, entailing mutagen/oxidant quenching. In our recent studies, however, most candidate phytochemical agents were not potent in inducing phase II genes in normal human lung cells. In this study, we applied a messenger RNA (mRNA)–specific gene expression–based high throughput in vitro screening approach to discover new, potent plant-derived phase II inducing chemopreventive agents. Primary normal human bronchial epithelial (NHBE) cells and immortalized human bronchial epithelial cells (HBECs) were exposed to 800 individual compounds in the MicroSource Natural Products Library. At a level achievable in humans by diet (1.0 μM), 2,3-dihydroxy-4-methoxy-4′-ethoxybenzophenone (DMEBP), triacetylresveratrol (TRES), ivermectin, sanguinarine sulfate, and daunorubicin induced reduced nicotinamide adenine dinucleotide phosphate:quinone oxidoreductase 1 (NQO1) mRNA and protein expression in NHBE cells. DMEBP and TRES were the most attractive agents as coupling potency and low toxicity for induction of NQO1 (mRNA level, ≥3- to 10.8-fold that of control; protein level, ≥ two- to fourfold that of control). Induction of glutathione S-transferase pi mRNA expression was modest, and none was apparent for glutathione S-transferase pi protein expression. Measurements of reactive oxygen species and glutathione/oxidized glutathione ratio showed an antioxidant effect for DMEBP, but no definite effect was found for TRES in NHBE cells. Exposure of NHBE cells to H2O2 induced nuclear translocation of nuclear factor erythroid 2–related factor 2, but this translocation was not significantly inhibited by TRES and DMEBP. These studies show that potency and low toxicity may align for two potential NQO1-inducing agents, DMEBP and TRES. PMID:22021338

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.

Glutathione S-transferase omega genes in Alzheimer and Parkinson disease risk, age-at-diagnosis and brain gene expression: an association study with mechanistic implications.

PubMed

Allen, Mariet; Zou, Fanggeng; Chai, High Seng; Younkin, Curtis S; Miles, Richard; Nair, Asha A; Crook, Julia E; Pankratz, V Shane; Carrasquillo, Minerva M; Rowley, Christopher N; Nguyen, Thuy; Ma, Li; Malphrus, Kimberly G; Bisceglio, Gina; Ortolaza, Alexandra I; Palusak, Ryan; Middha, Sumit; Maharjan, Sooraj; Georgescu, Constantin; Schultz, Debra; Rakhshan, Fariborz; Kolbert, Christopher P; Jen, Jin; Sando, Sigrid B; Aasly, Jan O; Barcikowska, Maria; Uitti, Ryan J; Wszolek, Zbigniew K; Ross, Owen A; Petersen, Ronald C; Graff-Radford, Neill R; Dickson, Dennis W; Younkin, Steven G; Ertekin-Taner, Nilüfer

2012-04-11

Glutathione S-transferase omega-1 and 2 genes (GSTO1, GSTO2), residing within an Alzheimer and Parkinson disease (AD and PD) linkage region, have diverse functions including mitigation of oxidative stress and may underlie the pathophysiology of both diseases. GSTO polymorphisms were previously reported to associate with risk and age-at-onset of these diseases, although inconsistent follow-up study designs make interpretation of results difficult. We assessed two previously reported SNPs, GSTO1 rs4925 and GSTO2 rs156697, in AD (3,493 ADs vs. 4,617 controls) and PD (678 PDs vs. 712 controls) for association with disease risk (case-controls), age-at-diagnosis (cases) and brain gene expression levels (autopsied subjects). We found that rs156697 minor allele associates with significantly increased risk (odds ratio = 1.14, p = 0.038) in the older ADs with age-at-diagnosis > 80 years. The minor allele of GSTO1 rs4925 associates with decreased risk in familial PD (odds ratio = 0.78, p = 0.034). There was no other association with disease risk or age-at-diagnosis. The minor alleles of both GSTO SNPs associate with lower brain levels of GSTO2 (p = 4.7 × 10-11-1.9 × 10-27), but not GSTO1. Pathway analysis of significant genes in our brain expression GWAS, identified significant enrichment for glutathione metabolism genes (p = 0.003). These results suggest that GSTO locus variants may lower brain GSTO2 levels and consequently confer AD risk in older age. Other glutathione metabolism genes should be assessed for their effects on AD and other chronic, neurologic diseases.

Gut Pathology and Responses to the Microsporidium Nosema ceranae in the Honey Bee Apis mellifera

PubMed Central

Dussaubat, Claudia; Brunet, Jean-Luc; Higes, Mariano; Colbourne, John K.; Lopez, Jacqueline; Choi, Jeong-Hyeon; Martín-Hernández, Raquel; Botías, Cristina; Cousin, Marianne; McDonnell, Cynthia; Bonnet, Marc; Belzunces, Luc P.; Moritz, Robin F. A.; Le Conte, Yves; Alaux, Cédric

2012-01-01

The microsporidium Nosema ceranae is a newly prevalent parasite of the European honey bee (Apis mellifera). Although this parasite is presently spreading across the world into its novel host, the mechanisms by it which affects the bees and how bees respond are not well understood. We therefore performed an extensive characterization of the parasite effects at the molecular level by using genetic and biochemical tools. The transcriptome modifications at the midgut level were characterized seven days post-infection with tiling microarrays. Then we tested the bee midgut response to infection by measuring activity of antioxidant and detoxification enzymes (superoxide dismutases, glutathione peroxidases, glutathione reductase, and glutathione-S-transferase). At the gene-expression level, the bee midgut responded to N. ceranae infection by an increase in oxidative stress concurrent with the generation of antioxidant enzymes, defense and protective response specifically observed in the gut of mammals and insects. However, at the enzymatic level, the protective response was not confirmed, with only glutathione-S-transferase exhibiting a higher activity in infected bees. The oxidative stress was associated with a higher transcription of sugar transporter in the gut. Finally, a dramatic effect of the microsporidia infection was the inhibition of genes involved in the homeostasis and renewal of intestinal tissues (Wnt signaling pathway), a phenomenon that was confirmed at the histological level. This tissue degeneration and prevention of gut epithelium renewal may explain early bee death. In conclusion, our integrated approach not only gives new insights into the pathological effects of N. ceranae and the bee gut response, but also demonstrate that the honey bee gut is an interesting model system for studying host defense responses. PMID:22623972

Gut pathology and responses to the microsporidium Nosema ceranae in the honey bee Apis mellifera.

PubMed

Dussaubat, Claudia; Brunet, Jean-Luc; Higes, Mariano; Colbourne, John K; Lopez, Jacqueline; Choi, Jeong-Hyeon; Martín-Hernández, Raquel; Botías, Cristina; Cousin, Marianne; McDonnell, Cynthia; Bonnet, Marc; Belzunces, Luc P; Moritz, Robin F A; Le Conte, Yves; Alaux, Cédric

2012-01-01

The microsporidium Nosema ceranae is a newly prevalent parasite of the European honey bee (Apis mellifera). Although this parasite is presently spreading across the world into its novel host, the mechanisms by it which affects the bees and how bees respond are not well understood. We therefore performed an extensive characterization of the parasite effects at the molecular level by using genetic and biochemical tools. The transcriptome modifications at the midgut level were characterized seven days post-infection with tiling microarrays. Then we tested the bee midgut response to infection by measuring activity of antioxidant and detoxification enzymes (superoxide dismutases, glutathione peroxidases, glutathione reductase, and glutathione-S-transferase). At the gene-expression level, the bee midgut responded to N. ceranae infection by an increase in oxidative stress concurrent with the generation of antioxidant enzymes, defense and protective response specifically observed in the gut of mammals and insects. However, at the enzymatic level, the protective response was not confirmed, with only glutathione-S-transferase exhibiting a higher activity in infected bees. The oxidative stress was associated with a higher transcription of sugar transporter in the gut. Finally, a dramatic effect of the microsporidia infection was the inhibition of genes involved in the homeostasis and renewal of intestinal tissues (Wnt signaling pathway), a phenomenon that was confirmed at the histological level. This tissue degeneration and prevention of gut epithelium renewal may explain early bee death. In conclusion, our integrated approach not only gives new insights into the pathological effects of N. ceranae and the bee gut response, but also demonstrate that the honey bee gut is an interesting model system for studying host defense responses.

Response of the antioxidant enzymes of the erythrocyte and alterations in the serum biomarkers in rats following oral administration of nanoparticles.

PubMed

Canli, Esin G; Atli, Gülüzar; Canli, Mustafa

2017-03-01

In this study, Al 2 O 3 , CuO and TiO 2 nanoparticles (NPs) were administered to mature female rats (Rattus norvegicus var. albinos) via oral gavage (0, 0.5, 5, 50mg/kg b.w./day) for 14days to investigate their effects on 14 serum biomarkers and 4 antioxidant enzyme (catalase, superoxide dismutase, glutathione peroxidase, glutathione S-transferase) activities in the erythrocyte. Data showed that Al 2 O 3 did not cause any significant (P>0.05) change in the parameters, except few cases, while CuO and TiO 2 caused significant alterations in antioxidant system parameters of the erythrocytes. Activities of catalase and superoxide dismutase significantly decreased in CuO and TiO 2 administered rats. Oppositely, glutathione peroxidase activity increased in CuO and TiO 2 administered rats. There were no significant alterations in the activity of glutathione S-transferase in the erythrocytes. Levels of glucose, cholesterol, bilirubin, triglyceride, triiodothyronine (T3), estradiol, prolactin and immunoglobulin M (IgM) in the serum altered after some of NP administrations, whereas cortisol, protein, creatinine, blood urea nitrogen (BUN), thyroxine (T4) and immunoglobulin G (IgG) levels in the serum did not change significantly after any of NP administration. There were outstanding increases in the levels of bilirubin and prolactin and decreases in the levels of triglyceride and estradiol. The present study demonstrated that the antioxidant enzymes in the erythrocyte were generally affected from copper and titanium NPs, while aluminium and copper NPs caused more significant alterations in serum biomarkers. Copyright © 2017 Elsevier B.V. All rights reserved.

Vitamin E Supplementation Ameliorates Newcastle Disease Virus-Induced Oxidative Stress and Alleviates Tissue Damage in the Brains of Chickens

PubMed Central

Rehman, Zaib Ur; Qiu, Xusheng; Sun, Yingjie; Liao, Ying; Tan, Lei; Song, Cuiping; Yu, Shengqing; Ding, Zhuang; Nair, Venugopal; Meng, Chunchun; Ding, Chan

2018-01-01

Newcastle disease (ND), characterized by visceral, respiratory, and neurological pathologies, causes heavy economic loss in the poultry industry around the globe. While significant advances have been made in effective diagnosis and vaccine development, molecular mechanisms of ND virus (NDV)-induced neuropathologies remain elusive. In this study, we report the magnitude of oxidative stress and histopathological changes induced by the virulent NDV (ZJ1 strain) and assess the impact of vitamin E in alleviating these pathologies. Comparative profiling of plasma and brains from mock and NDV-infected chicken demonstrated alterations in several oxidative stress makers such as nitric oxide, glutathione, malondialdehyde, total antioxidant capacity, glutathione S-transferase, superoxide dismutase, and catalases. While decreased levels of glutathione and total antioxidant capacity and increased concentrations of malondialdehyde and nitric oxide were observed in NDV-challenged birds at all time points, these alterations were eminent at latter time points (5 days post infection). Additionally, significant decreases in the activities of glutathione S-transferase, superoxide dismutase, and catalase were observed in the plasma and brains collected from NDV-infected chickens. Intriguingly, we observed that supplementation of vitamin E can significantly reduce the alteration of oxidative stress parameters. Under NDV infection, extensive histopathological alterations were observed in chicken brain including neural inflammation, capillary hyperemia, necrosis, and loss of prominent axons, which were reduced with the treatment of vitamin E. Taken together, our findings highlight that neurotropic NDV induces extensive tissue damage in the brain and alters plasma oxidative stress profiles. These findings also demonstrate that supplementing vitamin E ameliorates these pathologies in chickens and proposes its supplementation for NDV-induced stresses. PMID:29614025

Emergence of Plasmid-Mediated Fosfomycin-Resistance Genes among Escherichia coli Isolates, France.

PubMed

Benzerara, Yahia; Gallah, Salah; Hommeril, Baptiste; Genel, Nathalie; Decré, Dominique; Rottman, Martin; Arlet, Guillaume

2017-09-01

FosA, a glutathione S-transferase that inactivates fosfomycin, has been reported as the cause of enzymatic resistance to fosfomycin. We show that multiple lineages of FosA-producing extended spectrum β-lactamase Escherichia coli have circulated in France since 2012, potentially reducing the efficacy of fosfomycin in treating infections with antimicrobial drug-resistant gram-negative bacilli.

Anti-Angiogenic Action of Neutral Endopeptidase

DTIC Science & Technology

2007-11-01

message levels of NEP in hypoxia treated PC cells. Messenger RNA levels of NEP decreased between 50-75% relative to normoxic controls with high...GAGCATC-3 (sense) and 5-ATATGAATTCTCAGCTCT- TAGCAGACATGGAAGAAAG-3 ( antisense ) for glutathione S-transferase (GST) fusion proteins and 5-ATGGCAGCCGG...GAGCATC-3 (sense) and 5-CCCCAAGCTTTTAGCTCT- TAGCAGACAT-3 ( antisense ) for maltose-binding protein fusion proteins, as previously described (13

The biological activity of alpha-mangostin, a larvicidal botanic mosquito sterol carrier protein-2 inhibitor.

PubMed

Larson, Ryan T; Lorch, Jeffrey M; Pridgeon, Julia W; Becnel, James J; Clark, Gary G; Lan, Que

2010-03-01

alpha-Mangostin derived from mangosteen was identified as a mosquito sterol carrier protein-2 inhibitor via high throughput insecticide screening, alpha-Mangostin was tested for its larvicidal activity against third instar larvae of six mosquito species, and the median lethal concentration values range from 0.84 to 2.90 ppm. The residual larvicidal activity of alpha-mangostin was examined under semifield conditions. The results indicated that alpha-mangostin was photolytic with a half-life of 53 min in water under full sunlight exposure. The effect of alpha-mangostin on activities of major detoxification enzymes such as P450, glutathione S-transferase, and esterase was investigated. The results showed that alpha-mangostin significantly elevated activities of P450 and glutathione S-transferase in larvae, whereas it suppressed esterase activity. Toxicity of alpha-mangostin against young rats was studied, and there was no detectable adverse effect at dosages as high as 80 mg/kg. This is the first multifaceted study of the biological activity of alpha-mangostin in mosquitoes. The results suggest that alpha-mangostin may be a lead compound for the development of a new organically based mosquito larvicide.

The link between antioxidant enzymes catalase and glutathione S-transferase and physiological condition of a control population of terrestrial isopod (Porcellio scaber).

PubMed

Jemec, Anita; Lešer, Vladka; Drobne, Damjana

2012-05-01

The aim of this work was to investigate if the activities of catalase and glutathione S-transferase in a control population of terrestrial isopods (Porcellio scaber) are correlated with the physiological condition of the isopods. For this purpose, the activities of these enzymes were analysed in isopods from a stock population and in parallel, the physiological condition of the same specimens was assessed using a histological approach based on epithelial thickness and lipid droplets. We found a correlation between antioxidant enzymes and the physiological condition of the isopods. This implies that these enzymes could be used as predictive indicators of the physiological condition in a stock population before comprehensive toxicological studies are conducted and also in control group after the experiment. When a control group is found to be very heterogeneous in terms of physiological condition, the experiment should be repeated with a larger number of experimental animals. The findings of this study will contribute to more accurate experimental design of toxicity tests when using biomarkers. This should encourage other researchers to increase their effort to know the physiological state of their test organisms. Copyright © 2011 Elsevier Inc. All rights reserved.

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.

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.

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.

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.

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.

Effects of the commercial formulation containing fipronil on the non-target organism Cyprinus carpio: implications for rice-fish cultivation.

PubMed

Clasen, Bárbara; Loro, Vania Lucia; Cattaneo, Roberta; Moraes, Bibiana; Lópes, Thais; de Avila, Luis Antonio; Zanella, Renato; Reimche, Geovane Boschmann; Baldisserotto, Bernardo

2012-03-01

The aim of this research was to evaluate possible toxic effects of commercial formulation containing fipronil on Cyprinus carpio tissues under rice field conditions. Antioxidant profile (SOD, catalase, glutathione S-transferase), oxidative stress parameters (thiobarbituric acid-reactive substances, protein carbonyl), and growth were investigated in carp exposed to fipronil under rice field conditions for 7, 30, and 90 days. Waterborne insecticide concentrations were measured and the detectable concentration of fipronil was observed up to 45 day after application. Common carp survival and growth was not affected by fipronil. Liver superoxide dismutase activity was enhanced while liver catalase activity was inhibited at 7, 30, and 90 days. Alterations were not observed in the glutathione S-transferase activity in any experimental periods. Protein carbonyl increased only after 30 and 90 days of exposure. The thiobarbituric acid-reactive substances levels were enhanced in all analyzed tissues (liver, muscle, and brain) and periods of exposure. This study demonstrates that fipronil insecticides cause alterations in the biochemical parameters in different tissues of carp without affecting the growth or the survival of the fish. Copyright © 2011 Elsevier Inc. All rights reserved.

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.

Enzymatic characterization of insecticide resistance mechanisms in field populations of Malaysian Culex quinquefasciatus say (Diptera: Culicidae).

PubMed

Low, Van Lun; Chen, Chee Dhang; Lee, Han Lim; Tan, Tiong Kai; Chen, Chin Fong; Leong, Cherng Shii; Lim, Yvonne Ai Lian; Lim, Phaik Eem; Norma-Rashid, Yusoff; Sofian-Azirun, Mohd

2013-01-01

There has been no comprehensive study on biochemical characterization of insecticide resistance mechanisms in field populations of Malaysian Culex quinquefasciatus. To fill this void in the literature, a nationwide investigation was performed to quantify the enzyme activities, thereby attempting to characterize the potential resistance mechanisms in Cx. quinquefasciatus in residential areas in Malaysia. Culex quinquefasciatus from 14 residential areas across 13 states and one federal territory were subjected to esterases, mixed function oxidases, glutathione-S-transferase and insensitive acetylcholinesterase assays. Enzyme assays revealed that α-esterases and β-esterases were elevated in 13 populations and 12 populations, respectively. Nine populations demonstrated elevated levels of mixed function oxidases and glutathione-S-transferase. Acetylcholinesterase was insensitive to propoxur in all 14 populations. Activity of α-esterases associated with malathion resistance was found in the present study. In addition, an association between the activity of α-esterases and β-esterases was also demonstrated. The present study has characterized the potential biochemical mechanisms in contributing towards insecticide resistance in Cx. quinquefasciatus field populations in Malaysia. Identification of mechanisms underlying the insecticide resistance will be beneficial in developing effective mosquito control programs in Malaysia.

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 .

Revealing the role of glutathione S-transferase omega in age-at-onset of Alzheimer and Parkinson diseases.

PubMed

Li, Yi-Ju; Scott, William K; Zhang, Ling; Lin, Ping-I; Oliveira, Sofia A; Skelly, Tara; Doraiswamy, Maurali P; Welsh-Bohmer, Kathleen A; Martin, Eden R; Haines, Jonathan L; Pericak-Vance, Margaret A; Vance, Jeffery M

2006-08-01

We previously reported a linkage region on chromosome 10q for age-at-onset (AAO) of Alzheimer (AD) and Parkinson (PD) diseases. Glutathione S-transferase, omega-1 (GSTO1) and the adjacent gene GSTO2, located in this linkage region, were then reported to associate with AAO of AD and PD. To examine whether GSTO1 and GSTO2 (hereafter referred to as GSTO1h) are responsible for the linkage evidence, we identified 39 families in AD that lead to our previous linkage and association findings. The evidence of linkage and association was markedly diminished after removing these 39 families from the analyses, thus providing support that GSTO1h drives the original linkage results. The maximum average AAO delayed by GSTO1h SNP 7-1 (rs4825, A nucleotide) was 6.8 (+/-4.41) years for AD and 8.6(+/-5.71) for PD, respectively. This is comparable to the magnitude of AAO difference by APOE-4 in these same AD and PD families. These findings suggest the presence of genetic heterogeneity for GSTO1h's effect on AAO, and support GSTO1h's role in modifying AAO in these two disorders.

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.

Chemomodulatory effect of Moringa oleifera, Lam, on hepatic carcinogen metabolising enzymes, antioxidant parameters and skin papillomagenesis in mice.

PubMed

Bharali, Rupjyoti; Tabassum, Jawahira; Azad, Mohammed Rekibul Haque

2003-01-01

The modulatory effects of a hydro-alcoholic extract of drumsticks of Moringa oliefera Lam at doses of 125 mg/kg bodyweight and 250 mg/ kg body weight for 7 and 14 days, respectively, were investigated with reference to drug metabolising Phase I (Cytochrome b(5) and Cytochrome p(450) ) and Phase II (Glutathione-S- transferase) enzymes, anti-oxidant enzymes, glutathione content and lipid peroxidation in the liver of 6-8 week old female Swiss albino mice. Further, the chemopreventive efficacy of the extract was evaluated in a two stage model of 7,12 - dimethylbenz(a)anthracene induced skin papillomagenesis. Significant increase (p<0.05 to p<0.01) in the activities of hepatic cytochrome b(5), cytochrome p(450), catalase, glutathione peroxidase ( GPx ), glutathione reductase (GR), acid soluble sulfhydryl content (-SH ) and a significant decrease ( p<0.01 ) in the hepatic MDA level were observed at both dose levels of treatment when compared with the control values. Glutathione-S- transferase ( GST )activity was found to be significantly increased (p<0.01 ) only at the higher dose level. Butylated hydroxyanisol (BHA ) fed at a dose of 0.75% in the diet for 7 and 14 days (positive control ) caused a significant increase (p<0.05 to p<0.01) in the levels of hepatic phase I and phase II enzymes, anti- oxidant enzymes, glutathione content and a decrease in lipid peroxidation. The skin papillomagenesis studies demonstrated a significant decrease (p<0.05 ) in the percentage of mice with papillomas, average number of papillomas per mouse and papillomas per papilloma bearing mouse when the animals received a topical application of the extract at a dose of 5mg/ kg body weight in the peri-initiation phase 7 days before and 7 days after DMBA application, Group II ), promotional phase (from the day of croton oil application and continued till the end of the experiment, Group III ) and both peri and post initiation stages (from 7 days prior to DMBA application and continued till the end of the experiment, Group IV) compared to the control group (Group I ). The percentage inhibition of tumor multiplicity has been recorded to be 27, 72, and 81 in Groups II, III, and IV, respectively. These findings are suggestive of a possible chemopreventive potential of Moringa oliefera drumstick extract against chemical carcinogenesis.

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.

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

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.

Biochemical response of anthracene and benzo [a] pyrene in milkfish Chanos chanos.

PubMed

Palanikumar, L; Kumaraguru, A K; Ramakritinan, C M; Anand, M

2012-01-01

Polycyclic aromatic hydrocarbons (PAHs) are common toxic pollutants found in the aquatic environment, and the assessment of their impact on biota is of considerable concern. The aim of the present research was to study the acute toxicity, bioaccumulation and biochemical response of milkfish Chanos chanos (Forsskal) to two selected PAHs: anthracene and benzo [a] pyrene. Acute toxicity test results were evaluated by the Probit analysis method and 96h LC(50) values for C. chanos exposed to anthracene was 0.030mgl(-1) and 0.014mgl(-1) for benzo [a] pyrene. Bioaccumulation concentration of anthracene was high when compared to benzo [a] pyrene. Biomarkers indicative of neurotoxicity (acetylcholinesterase, AchE), oxidative stress (lipid peroxidation, LPO and catalase, CAT) and phase II biotransformation of xenobiotics (glutathione S transferase, GST and reduced glutathione, GSH) were measured to assess effects of selected PAHs. Anthracene and benzo [a] pyrene increase LPO and CAT level of C. chanos suggesting that these PAHs may induce oxidative stress. Both the PAHs inhibited AchE indicating that they have at least one mechanism of neurotoxicity in common: the disruption of cholinergic transmission by inhibition of AChE. An induction of C. chanos glutathione S-transferase (GST) activity was found in fish exposed to benzo [a] pyrene, while an inhibition was observed after exposure to anthracene. These results suggest that GST is involved in the detoxification of benzo [a] pyrene, but not of anthracene. Copyright © 2011 Elsevier Inc. All rights reserved.

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.

An experimental evaluation of the anti-atherogenic potential of the plant, Piper betle, and its active constitutent, eugenol, in rats fed an atherogenic diet.

PubMed

Venkadeswaran, Karuppasamy; Thomas, Philip A; Geraldine, Pitchairaj

2016-05-01

Hypercholesterolemia is a major risk factor for systemic atherosclerosis and subsequent cardiovascular disease. Lipoperoxidation-mediated oxidative damage is believed to contribute strongly to the progression of atherogenesis. In the current investigation, putative anti-atherogenic and antioxidative properties of an ethanolic extract of Piper betle and of its active constituent, eugenol, were sought in an experimental animal model of chronic hypercholesterolemia. Atherogenic diet-fed rats that received either Piper betle extract orally (500mg/kg b.wt) or eugenol orally (5mg/kg b.wt) for 15days (commencing 30days after the atherogenic diet had been started) exhibited the following variations in different parameters, when compared to atherogenic diet-fed rats that received only saline: (1) significantly lower mean levels of total cholesterol, triglycerides, low-density lipoprotein cholesterol and very low density lipoprotein cholesterol in both serum and hepatic tissue samples; (2) lower mean serum levels of aspartate amino-transferase, alanine amino-transferase, alkaline phosphatase, lactate dehydrogenase and lipid-metabolizing enzymes (lipoprotein lipase, 3-hydroxy-3-methyl-glutaryl-CoA reductase; (3) significantly lower mean levels of enzymatic antioxidants (catalase, superoxide dismutase, glutathione peroxidase, glutathione-S-transferase) and non-enzymatic antioxidants (reduced glutathione, vitamin C and vitamin E) and significantly higher mean levels of malondialdehyde in haemolysate and hepatic tissue samples. Histopathological findings suggested a protective effect of the Piper betle extract and a more pronounced protective effect of eugenol on the hepatic and aortic tissues of atherogenic diet-fed (presumed atherosclerotic) rats. These results strongly suggest that the Piper betle extract and its active constituent, eugenol, exhibit anti-atherogenic effects which may be due to their anti-oxidative properties. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Modulatory role of Pterocarpus santalinus against alcohol-induced liver oxidative/nitrosative damage in rats.

PubMed

Bulle, Saradamma; Reddy, Vaddi Damodara; Padmavathi, Pannuru; Maturu, Paramahamsa; N Ch, Varadacharyulu

2016-10-01

Pterocarpus santalinus, a traditional medicinal plant has shown protective mechanisms against various complications. The aim of the present study is to evaluate therapeutic efficacy of P. santalinus heartwood methanolic extract (PSE) against alcohol-induced oxidative/nitrosative stress leading to hepatotoxicity. In-vitro studies revealed that PSE possess strong DPPH (1,1-diphenyl-2-picryl hydrazyl) and nitric oxide radical scavenging activity. For in vivo studies male albino Wistar rats were treated with 20% alcohol (5g/kg b.wt/day) and PSE (250mg/kg b.wt/day) for 60days. Results showed that alcohol administration significantly altered plasma lipid profile with marked increase in the levels of plasma transaminases (ALT and AST), alkaline phosphatase (ALP), lactate dehydrogenase (LDH) and gamma glutamyl transferase (γGT). Moreover, lipid peroxides, nitric oxide (NOx) levels in plasma and liver were increased with increased iNOS protein expression in liver was noticed in alcohol administered rats and these levels were significantly brought back close to normal level by PSE administration except iNOS protein expression. Alcohol administration also decreased the content of reduced glutathione (GSH) and activities of glutathione peroxidase (GPx), glutathione-s transferase (GST), glutathione reductase (GR), superoxide dismutase (SOD) and catalase (CAT) in liver, which were significantly enhanced by administration of PSE. The active compounds pterostilbene, lignan and lupeols present in PSE might have shown protection against alcohol-induced hepatic damage by possibly reducing the rate of lipid peroxidation, NOx levels and increasing the antioxidant defence mechanism in alcohol administered rats. Both biochemical and histopathological results in the alcohol-induced liver damage model emphasize beneficial action of PSE as a hepatoprotective agent. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Chemopreventive efficacy of a betel leaf extract against benzo[a]pyrene-induced forestomach tumors in mice.

PubMed

Bhide, S V; Zariwala, M B; Amonkar, A J; Azuine, M A

1991-09-01

The effect of betel leaf extract and some of its constituents, eugenol, hydroxychavicol, beta-carotene and alpha-tocopherol, on benzo[a]pyrene-induced forestomach neoplasia in male Swiss mice was examined. Betel leaf and its constituents decreased the number of papillomas per animal with the maximum protection, considering molar dosage, exhibited by beta-carotene and alpha-tocopherol. Except for beta-carotene, eugenol, hydroxychavicol and alpha-tocopherol increased the levels of reduced glutathione in the liver while glutathione S-transferase activity was enhanced by all except eugenol. Of seven sources, Banarasi betel leaves showed the maximum amounts of beta-carotene and alpha-tocopherol.

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.

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

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

Oral Sulforaphane increases Phase II antioxidant enzymes in the human upper airway

PubMed Central

Riedl, Marc A.; Saxon, Andrew; Diaz-Sanchez, David

2009-01-01

Background Cellular oxidative stress is an important factor in asthma and is thought to be the principle mechanism by which oxidant pollutants such as ozone and particulates mediate their pro-inflammatory effects. Endogenous Phase II enzymes abrogate oxidative stress through the scavenging of reactive oxygen species and metabolism of reactive chemicals. Objective We conducted a placebo-controlled dose escalation trial to investigate the in vivo effects of sulforaphane, a naturally occurring potent inducer of Phase II enzymes, on the expression of glutathione-s-transferase M1 (GSTM1), glutathione-s-transferase P1 (GSTP1), NADPH quinone oxidoreductase (NQO1), and hemoxygenase-1 (HO-1) in the upper airway of human subjects. Methods Study subjects consumed oral sulforaphane doses contained in a standardized broccoli sprout homogenate (BSH). RNA expression for selected Phase II enzymes was measured in nasal lavage cells by RT-PCR before and after sulforaphane dosing. Results All subjects tolerated oral sulforaphane dosing without significant adverse events. Increased Phase II enzyme expression in nasal lavage cells occurred in a dose-dependent manner with maximal enzyme induction observed at the highest dose of 200 grams broccoli sprouts prepared as BSH. Significant increases were seen in all sentinel Phase II enzymes RNA expression compared to baseline. Phase II enzyme induction was not seen with ingestion of non-sulforaphane containing alfalfa sprouts. Conclusion Oral sulforaphane safely and effectively induces mucosal Phase II enzyme expression in the upper airway of human subjects. This study demonstrates the potential of antioxidant Phase II enzymes induction in the human airway as a strategy to reduce the inflammatory effects of oxidative stress. Clinical Implications This study demonstrates the potential of enhancement of Phase II enzyme expression as a novel therapeutic strategy for oxidant induced airway disease. Capsule Summary A placebo-controlled dose escalation trial demonstrated that naturally occurring sulforaphane from broccoli sprouts can induce a potent increase in antioxidant Phase II enzymes in airway cells. PMID:19028145

Glutathione S-Transferase Pi Isoform (GSTP1) Expression in Murine Retina Increases with Developmental Maturity

PubMed Central

Lee, Wen-Hsiang; Joshi, Pratibha; Wen, Rong

2014-01-01

Background and Aims Glutathione S-transferase pi isoform (GSTP1) is an intracellular detoxification enzyme that catalyzes reduction of chemically reactive electrophiles and is a zeaxanthin-binding protein in the human macula. We have previously demonstrated that GSTP1 levels are decreased in human age-related macular degeneration (AMD) retina compared to normal controls [1]. We also showed that GSTP1 levels parallel survival of human retinal pigment epithelial (RPE) cells exposed to UV light, and GSTP1 over-expression protects them against UV light damage [2]. In the present work, we determined the developmental time course of GSTP1 expression in murine retina and in response to light challenge. Methods Eyes from BALB/c mice at post-natal day 20, 1 month, and 2 months of age were prepared for retinal protein extraction and cryo sectioning, and GSTP1 levels in the retina were analyzed by Western blot and immunohistochemistry (IHC). Another group of BALB/c mice with the same age ranges was exposed to 1000 lux of white fluorescent light for 24 hours, and their retinas were analyzed for GSTP1 expression by Western blot and IHC in a similar manner. Results GSTP1 levels in the murine retina increased in ascending order from post-natal day 20, 1 month, and 2 months of age. Moreover, GSTP1 expression in murine retina at post-natal day 20, 1 month, and 2 months of age increased in response to brief light exposure compared to age-matched controls under normal condition. Conclusions GSTP1 expression in retina increases with developmental age in mice and accompanies murine retinal maturation. Brief exposure to light induces GSTP1 expression in the murine retina across various developmental ages. GSTP1 induction may be a protective response to light-induced oxidative damage in the murine retina. PMID:24664677

Oxidative Stress-Related Genetic Variants May Modify Associations of Phthalate Exposures with Asthma

PubMed Central

Wang, I-Jen; Karmaus, Wilfried J. J.

2017-01-01

Background: Phthalate exposure may increase the risk of asthma. Little is known about whether oxidative-stress related genes may alter this association. First, this motivated us to investigate whether genetic polymorphisms of the oxidative-stress related genes glutathione S-transferase Mu 1 (GSTM1), glutathione S-transferase pi 1 (GSTP1), superoxide dismutase 2 (SOD2), catalase (CAT), myeloperoxidase (MPO), and EPHX1 in children are associated with phthalate urine concentrations. Second, we addressed the question whether these genes may affect the influence of phthalates on asthma. Methods: In a case-control study composed of 126 asthmatic children and 327 controls, urine phthalate metabolites (monoethyl phthalate (MEP), monobutyl phthalate (MBP), monobenzyl phthalate (MBzP), and mono(2-ethyl-5-hydroxyhexyl)phthalate (MEHHP) were measured by UPLC-MS/MS at age 3. Genetic variants were analyzed by TaqMan assay. Information on asthma and environmental exposures was also collected. Analyses of variance and logistic regressions were performed. Results: Urine MEHHP levels were associated with asthma (adjusted OR 1.33, 95% CI (1.11–1.60). Children with the GSTP1 (rs1695) AA and SOD2 (rs5746136) TT genotypes had higher MEHHP levels as compared to GG and CC types, respectively. Since only SOD2 TT genotype was significantly associated with asthma (adjusted OR (95% CI): 2.78 (1.54–5.02)), we estimated whether SOD2 variants modify the association of MEHHP levels and asthma. As MEHHP concentrations were dependent on GSTP1 and SOD2, but the assessment of interaction requires independent variables, we estimated MEHHP residuals and assessed their interaction, showing that the OR for SOD2 TT was further elevated to 3.32 (1.75–6.32) when the residuals of MEHHP were high. Conclusions: Urine phthalate metabolite concentrations are associated with oxidative-stress related genetic variants. Genetic variants of SOD2, considered to be reflect oxidative stress metabolisms, might modify the association of phthalate exposure with asthma. PMID:28208751

Oxidative Stress-Related Genetic Variants May Modify Associations of Phthalate Exposures with Asthma.

PubMed

Wang, I-Jen; Karmaus, Wilfried J J

2017-02-08

Background: Phthalate exposure may increase the risk of asthma. Little is known about whether oxidative-stress related genes may alter this association. First, this motivated us to investigate whether genetic polymorphisms of the oxidative-stress related genes glutathione S -transferase Mu 1 ( GSTM1 ), glutathione S -transferase pi 1 ( GSTP1 ), superoxide dismutase 2 ( SOD2 ), catalase ( CAT ), myeloperoxidase ( MPO ), and EPHX1 in children are associated with phthalate urine concentrations. Second, we addressed the question whether these genes may affect the influence of phthalates on asthma. Methods: In a case-control study composed of 126 asthmatic children and 327 controls, urine phthalate metabolites (monoethyl phthalate (MEP), monobutyl phthalate (MBP), monobenzyl phthalate (MBzP), and mono(2-ethyl-5-hydroxyhexyl)phthalate (MEHHP) were measured by UPLC-MS/MS at age 3. Genetic variants were analyzed by TaqMan assay. Information on asthma and environmental exposures was also collected. Analyses of variance and logistic regressions were performed. Results: Urine MEHHP levels were associated with asthma (adjusted OR 1.33, 95% CI (1.11-1.60). Children with the GSTP1 (rs1695) AA and SOD2 (rs5746136) TT genotypes had higher MEHHP levels as compared to GG and CC types, respectively. Since only SOD2 TT genotype was significantly associated with asthma (adjusted OR (95% CI): 2.78 (1.54-5.02)), we estimated whether SOD2 variants modify the association of MEHHP levels and asthma. As MEHHP concentrations were dependent on GSTP1 and SOD2 , but the assessment of interaction requires independent variables, we estimated MEHHP residuals and assessed their interaction, showing that the OR for SOD2 TT was further elevated to 3.32 (1.75-6.32) when the residuals of MEHHP were high. Conclusions: Urine phthalate metabolite concentrations are associated with oxidative-stress related genetic variants. Genetic variants of SOD2 , considered to be reflect oxidative stress metabolisms, might modify the association of phthalate exposure with asthma.

Prevalence of Null Genotypes of Glutathione S-Transferase T1 (GSTT1) and M1 (GSTM1) in Seven Iranian Populations

PubMed Central

NASSERI, Gholamreza; ZAHEDI, Tahereh; MOUSAVI-KAZEROONI, Fatemeh; SAADAT, Mostafa

2015-01-01

Background: Previous studies have revealed significant differences between populations for genotypic frequencies of glutathione S-transferase T1 (GSTT1) and M1 (GSTM1) polymorphisms. In order to find the frequency of the null genotypes of GSTM1 and GSTT1 in Iranian populations, the present study was carried out. Methods: The total study subjects consisted of 1340 unrelated healthy Muslims/Iranian. From these 297, 200, 123, 168, 152, 200, and 200 individuals from Tabriz (East Azerbaijan Province; belong to Azaris), Yasuj (Kohgiluyeh-va-Boyerahmad Province; belong to Lurs), Abarku (Yazd Province; belong to Persians), Zahedan (Sistan-va-Balouchestan Province; belong to Balouchis), Zahedan (Sistan-va-Balouchestan Province; belong to Sistanis), Kermanshah (Kermanshah Province; belong to Kurds), and Gorgan (Golestan Province; belong to Turkmen) respectively. The genotypes were detected by multiplex PCR. Results: The frequency of GSTM1 null genotype among Azaris, Lurs, Persians, Balouchis, Sistanis, Kurds, and Turkmen was 43.8, 50.0, 52.0, 50.0, 51.3, 56.0, and 53.0%, respectively. There was no significant difference between these populations for the genotypic distribution of the GSTM1 polymorphism (χ2=8.47, df=6, P=0.206). The frequency of GSTT1 null genotype among Azaris, Lurs, Persians, Balouchis, Sistanis, Kurds, and Turkmen was 18.2, 17.0, 29.3, 20.8, 17.8, 18.5, and 23.0%, respectively. There was very similarity between Azaris, Kurds and Lurs for the frequency of GSTT1 genotypes (χ2=0.17, df=2, P=0.916). Conclusion: By comparing the frequency of GSTT1 genotypes among Iranian populations, Caucasians and Asians, it is concluded that Azaris, Kurds and Lurs were similar to each other. Taken together, it is suggested that although Azaris are Turkish speaking belong to Caucasians. PMID:26811816

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.

Improved diagnostic performance of a commercial anaplasma antibody competitive enzyme-linked immunosorbent assay using recombinant major surface protein 5–glutathione S-transferase fusion protein as antigen

USDA-ARS?s Scientific Manuscript database

This study tested the hypothesis that removal of maltose binding protein from recombinant antigen used for plate coating would improve the specificity of Anaplasma antibody competitive ELISA. Three hundred and eight sera with significant MBP antibody binding (=30%I) in Anaplasma negative herds was 1...

THE ROLE OF HUMAN GLUTATHIONE S-TRANSFERASES (HGSTS) IN THE DETOXIFICATION OF THE FOOD-DERIVED CARCINOGEN METABOLITE N-ACETOXY-PHIP, AND THE EFFECT OF A POLYMORPHISM IN HGSTA1 ON COLORECTAL CANCER RISK. (R825280)

EPA Science Inventory

The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

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.

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.

Dietary isothiocyanates, glutathione S-transferase M1 (GSTM1), and lung cancer risk in African Americans and Caucasians from Los Angeles County, California.

PubMed

Carpenter, Catherine L; Yu, Mimi C; London, Stephanie J

2009-01-01

Isothiocyanates, found in cruciferous vegetables, are anticarcinogenic. Racial differences in smoking do not fully account for the African-American excess lung cancer incidence. African Americans consume more cruciferous vegetables than U.S. Whites. Impact on lung cancer risk is unknown. The glutathione S transferase M1 (GSTM1) gene promotes urinary isothiocyanate excretion. We evaluated dietary isothiocyanates and lung cancer using a population-based case-control study of 933 African Americans and Caucasians (non-Hispanic U.S. White) from Los Angeles County, California (311 cases; 622 controls). Broccoli, cauliflower, greens, and cabbage food-frequency variables represented isothiocyanates. Isothiocyanates were protective for lung cancer risk. Adjusted odds ratio (OR) for the uppermost quartile > 80 micro mol isothiocyanates/wk, compared to lowest, was 0.65 [95% confidence interval (CI) = 0.41-1.00, trend P = 0.02]. Association was stronger among subjects with homozygous deletion of GSTM1 (OR = 0.52, 95% CI = 0.31-0.86) than subjects with at least one GSTM1 copy (OR = 0.77, 95% CI = 0.49-1.21). The difference was not statistically significant (P = 0.16). Despite African Americans consuming more cruciferous vegetables, the isothiocyanate association did not vary by race (P = 0.52). Reduced lung cancer risk with higher isothiocyanate intake may be slightly stronger among subjects with deletion of GSTM1.

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.

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.

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.

Glutathione S-transferase pi modulates NF-κB activation and pro-inflammatory responses in lung epithelial cells.

PubMed

Jones, Jane T; Qian, Xi; van der Velden, Jos L J; Chia, Shi Biao; McMillan, David H; Flemer, Stevenson; Hoffman, Sidra M; Lahue, Karolyn G; Schneider, Robert W; Nolin, James D; Anathy, Vikas; van der Vliet, Albert; Townsend, Danyelle M; Tew, Kenneth D; Janssen-Heininger, Yvonne M W

2016-08-01

Nuclear Factor kappa B (NF-κB) is a transcription factor family critical in the activation of pro- inflammatory responses. The NF-κB pathway is regulated by oxidant-induced post-translational modifications. Protein S-glutathionylation, or the conjugation of the antioxidant molecule, glutathione to reactive cysteines inhibits the activity of inhibitory kappa B kinase beta (IKKβ), among other NF-κB proteins. Glutathione S-transferase Pi (GSTP) is an enzyme that has been shown to catalyze protein S-glutathionylation (PSSG) under conditions of oxidative stress. The objective of the present study was to determine whether GSTP regulates NF-κB signaling, S-glutathionylation of IKK, and subsequent pro-inflammatory signaling. We demonstrated that, in unstimulated cells, GSTP associated with the inhibitor of NF-κB, IκBα. However, exposure to LPS resulted in a rapid loss of association between IκBα and GSTP, and instead led to a protracted association between IKKβ and GSTP. LPS exposure also led to increases in the S-glutathionylation of IKKβ. SiRNA-mediated knockdown of GSTP decreased IKKβ-SSG, and enhanced NF-κB nuclear translocation, transcriptional activity, and pro-inflammatory cytokine production in response to lipopolysaccharide (LPS). TLK117, an isotype-selective inhibitor of GSTP, also enhanced LPS-induced NF-κB transcriptional activity and pro-inflammatory cytokine production, suggesting that the catalytic activity of GSTP is important in repressing NF-κB activation. Expression of both wild-type and catalytically-inactive Y7F mutant GSTP significantly attenuated LPS- or IKKβ-induced production of GM-CSF. These studies indicate a complex role for GSTP in modulating NF-κB, which may involve S-glutathionylation of IKK proteins, and interaction with NF-κB family members. Our findings suggest that targeting GSTP is a potential avenue for regulating the activity of this prominent pro-inflammatory and immunomodulatory transcription factor. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

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.

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.

Phytoremediation of Ni-contaminated soil by Salicornia iranica.

PubMed

Kaviani, Elina; Niazi, Ali; Moghadam, Ali; Taherishirazi, Mohsen; Heydarian, Zohreh

2017-10-16

Although nickel (Ni) is useful and is used in various industries, it is one of the most usual and important sources of heavy metals pollutants in the world. In this study, Salicornia iranica was used in order to phytoremediate Ni-contaminated soil. Possible mechanisms of plant tolerance to Ni pollution and its detoxification were studied through using expression analysis of glutathione-S-transferase (GST) and measurement of involved key physiological components. The concentration of the chlorophylls a, b, total chlorophyll, and carotenoids were significantly decreased in 500 mg/kg Ni at 3, 24, 48 h, and 90 days after the treatment. Free proline significantly increased in the tissues. The absorption and concentration of Ni increased in tissues, so that Ni concentration at 50, 250, and 500 mg Ni/kg soil significantly increased to 2.5, 3.5, and 4.5 fold compared with the lowest Ni level respectively. In addition, the GST expression was significantly increased both in the 50 and 500 mg/kg Ni treatment. The highest concentration of Ni affected plant growth parameters such as the root and shoot lengths. Therefore, S. iranica is able to accumulate Ni and it can be used as an environmental biotechnological study for phytoremediation of Ni-polluted soils. ABA: abscisic acid; ABRE: ABA-responsive element; As +3 : arsenic; Cd 2+ : cadmium; ef1: elongation factor; FW: fresh weight; GSH: glutathione; GST: glutathione-S-transferase; GSTU: tau class GST; Hcl: hydrochloric acid; Hg 2+ : mercury; HgCl 2 : mercury(II) chloride; MYB: myeloblastosis viral oncogene homolog; Ni +2 : nickel; Pb: lead; SiGSTU: Salicornia iranica GSTU; ZnSO 4 : zinc sulfate.

Nitrobenzoxadiazole-based GSTP1-1 inhibitors containing the full peptidyl moiety of (pseudo)glutathione.

PubMed

Luisi, Grazia; Mollica, Adriano; Carradori, Simone; Lenoci, Alessia; De Luca, Anastasia; Caccuri, Anna Maria

2016-12-01

The inhibition of glutathione S-transferase P1-1 (GSTP1-1) is a sound strategy to overcome drug resistance in oncology practice. The nitrobenzoxadiazolyl (NBD) S-conjugate of glutathione and the corresponding γ-oxa-glutamyl isostere (compounds 1 and 5, respectively) have been disclosed as GST inhibitors. The rationale of their design is discussed in juxtaposition to non-peptide NBD thioethers. Synthesis of derivatives 1 and 5 and in vitro evaluation on human GSTP1-1 and M2-2 are reported. Conjugates 1 and 5 were found to be low micromolar inhibitors of both isoforms. Furthermore, they display a threefold reduction in selectivity for GSTM2-2 over the P1-1 isozyme in comparison with the potent non-peptide inhibitor nitrobenzoxadiazolyl-thiohexanol (NBDHEX). Spectroscopic data are congruent with the formation of a stable sigma-complex between GSH and the inhibitors in the protein active site. Conjugate 5 is suitable for in vivo modulation of GST activity in cancer treatment.

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.

Antioxidant and drug detoxification potentials of Hibiscus sabdariffa anthocyanin extract.

PubMed

Ajiboye, Taofeek O; Salawu, Nasir A; Yakubu, Musa T; Oladiji, Adenike T; Akanji, Musbau A; Okogun, Joseph I

2011-04-01

The antioxidant and drug metabolizing potentials of Hibiscus anthocyanin extract in CCl(4)- induced oxidative damage of rat liver was investigated. Hibiscus anthocyanin extract effectively scavenge α-diphenyl-β-picrylhydrazyl (DPPH) radical, superoxide ion, and hydrogen peroxide. It produced a 92% scavenging effect of DPPH radical at a concentration of 2.0 mg/mL. Hibiscus anthocyanin extract produced a 69 and 90% scavenging effect on superoxide ion and hydrogen peroxide, respectively, at 1.0 mg/mL, which compared favorably with the synthetic antioxidant (butylated hydroanisole and α-tocopherol). A reducing power of this anthocyanin was examined using K(3)Fe(CN)(6). Hibiscus anthocyanin extract has reducing power that is approximately 2-fold that of the synthetic antioxidant, butylated hydroanisole. Hibiscus anthocyanin extract produced a significantly increase and completely attenuated the CCl(4)-mediated decrease in antioxidant enzymes (e.g., catalase, superoxide dismutase, glutathione peroxidase, and glutathione reductase). However, the level of nonenzymic antioxidant molecules (i.e., vitamins C and E) were significant preserved by Hibiscus anthocyanin extract. There was an induction of phase II drug-detoxifying enzymes: glutathione S-transferase, NAD(H):quinone oxidoreductase, and uridyl diphosphoglucuronosyl transferase by 65, 45, and 57%, respectively. In view of these properties, Hibiscus sabdariffa anthocyanin extract can act as a prophylactic by intervening as a free radical scavenger both in vitro and in vivo as well as inducing the phase II drug detoxification enzymes.

Biological effects of diethylene glycol (DEG) and produced waters (PWs) released from offshore activities: a multi-biomarker approach with the sea bass Dicentrarchus labrax.

PubMed

Stefania, Gorbi; Maura, Benedetti; Claudia, Virno Lamberti; Barbara, Pisanelli; Ginevra, Moltedo; Francesco, Regoli

2009-11-01

Diethylene glycol (DEG) is largely used during oil and gas exploitation by offshore platforms. The aim of this work was to investigate if this compound induces direct molecular/cellular effects in marine organisms, or indirectly modulate those of produced waters (PWs). Sea bass (Dicentrarchus labrax) were exposed to DEG dosed alone or in combination with PWs from an Adriatic platform. A wide array of analysed biomarkers included cytochrome P450-dependent enzymatic activity, bile metabolites, glutathione S-transferases, acetylcholinesterase, peroxisomal proliferation, antioxidant defences (catalase, glutathione reductase, glutathione peroxidases, glutathione), total oxyradical scavenging capacity, malondialdehyde and DNA integrity (single strand breaks and frequency of micronuclei). Results did not reveal marked effects of DEG, while PWs influenced the biotransformation system, the oxidative status and the onset of genotoxic damages. Co-exposures caused only limited differences of biomarker responses at some experimental conditions, overall suggesting a limited biological impact of DEG at levels normally deriving from offshore activities.

A single acute hepatotoxic dose of CCl4 causes oxidative stress in the rat brain.

PubMed

Ritesh, K R; Suganya, A; Dileepkumar, H V; Rajashekar, Y; Shivanandappa, T

2015-01-01

Carbon tetrachloride (CCl 4 ), a hepatotoxic agent is widely used to study the toxic mechanisms in experimental animals. We have investigated whether oxidative stress is induced in the brain at a single hepatotoxic dosage (1 ml/kg bw) of CCl 4 . Increased lipid peroxidation (LPO), protein carbonyls (PC) content and glutathione (GSH) depletion were observed in the brain regions of rats treated with CCl 4 which was higher than that of liver. A drastic reduction in the activity of glutathione- S -transferase (GST) was seen in the brain regions which was higher than that of liver. Similarly, activities of glutathione peroxidase (GPx), glutathione reductase (GR), superoxide dismutase (SOD), catalase (CAT), NADH- and NADPH-dehydrogenase were reduced in the brain regions similar to that of liver. Higher induction of oxidative stress in the brain compared to that of liver implies vulnerability of the brain for CCl 4 neurotoxicity. Our study shows that a single hepatotoxic dose of CCl 4 is equally neurotoxic to rats.

Reciprocal effects of caulerpenyne and intense herbivorism on the antioxidant response of Bittium reticulatum and Caulerpa taxifolia.

PubMed

Sureda, Antoni; Box, Antonio; Deudero, Salud; Pons, Antoni

2009-03-01

We studied the antioxidant enzyme response of the gastropoda Bittium reticulatum feeding the toxic alga Caulerpa taxifolia, and also the effects of intense herbivorism on caulerpenyne production and on the antioxidant response of C. taxifolia. B. reticulatum were maintained in two separated aquariums containing Posidonia oceanica or C. taxifolia. Glutathione peroxidase, glutathione reductase and glutathione S-transferase activities were significantly higher in B. reticulatum living in presence of C. taxifolia with respect to animals living in P. oceanica aquarium. Malondialdehyde levels in B. reticulatum showed similar values in both environments. Caulerpenyne levels were significantly higher in C. taxifolia fronds after herbivore exposure. C. taxifolia activities of catalase and glutathione reductase significantly increased in presence of B. reticulatum. B. reticulatum exposed to caulerpenyne evidenced antioxidant enzyme adaptations to prevent oxidative damage. The presence of B. reticulatum in the aquarium induces a protective adaptation in C. taxifolia in order to reduce the herbivorism.

Protective Effect of Ethanol Extracts of Hericium erinaceus on Alloxan-Induced Diabetic Neuropathic Pain in Rats

PubMed Central

Yi, Zhang; Shao-long, Yang; Ai-hong, Wang; Zhi-chun, Sun; Ya-fen, Zhuo; Ye-ting, Xu; Yu-ling, He

2015-01-01

We investigated the effects of Hericium erinaceus (HEE) on alloxan induced diabetic neuropathic pain in laboratory rats. Alloxan induced diabetic rats were administered orally HEE. After 6 weeks of treatments, treatment with HEE 40 mg/kg in diabetic animals showed significant increase in pain threshold and paw withdrawal threshold and significant decrease in serum glucose and urine glucose. We also observed a significant increase in lactate dehydrogenase (LDH), Lipid peroxidation (LPO), glutathione peroxidase (GPx) activity, glutathione reductase (GR) activity, catalase (CAT) activity, Na+K+ATPase activity, and glutathione S transferase (GST) activity along with significant decreased levels of glutathione (GSH) content in diabetic rats. The total antioxidant status (TAOS) in the HEE-treated groups was significantly lower than that in the alloxan-treated group. HEE can offer pain relief in diabetic neuropathic pain. The improvement in diabetic state after HEE treatment along with the antioxidant activity could be the probable way by which it had alleviated diabetic neuropathy. PMID:25960754

Protoapigenone, a natural derivative of apigenin, induces mitogen-activated protein kinase-dependent apoptosis in human breast cancer cells associated with induction of oxidative stress and inhibition of glutathione S-transferase π.

PubMed

Chen, Wen-Ying; Hsieh, Yu-An; Tsai, Ching-I; Kang, Ya-Fei; Chang, Fang-Rong; Wu, Yang-Chang; Wu, Chin-Chung

2011-12-01

Protoapigenone, a natural derivative of the flavonoid apigenin, has been shown to exhibit potent antitumor activity in vitro and in vivo; the precise mechanism of action, however, is not fully elucidated. In this study, we investigated and compared the mechanisms by which protoapigenone and apigenin caused cell death in the human breast cancer MDA-MB-231 cells. Flow cytometry analysis revealed that protoapigenone induced apoptosis with 10-fold greater potency than apigenin. Cancer cells treated with protoapigenone resulted in persistent activation of mitogen-activated protein kinase (MAPK) ERK, JNK, and p38, hyperphosphorylation of Bcl-2 and Bcl-xL, and loss of mitochondrial membrane potential (MMP). The MAPK inhibitors effectively prevented the loss of MMP and apoptosis induced by protoapigenone. Treatment of cells with protoapigenone led to increased levels of reactive oxygen species (ROS) and decreased levels of intracellular glutathione. The thiol-antioxidant N-acetylcysteine abolished protoapigenone-induced MAPK activation, mitochondrial dysfunction, and apoptosis. These results suggest that the induction of oxidative stress preceding the activation of MAPK is required to initiate the mitochondria-mediated apoptosis induced by protoapigenone. Additionally, protoapigenone-induced JNK activation was linked to thiol modification of glutathione S-transferase π (GSTpi), which impeded GSTpi inhibition of JNK. In contrast to protoapigenone, apigenin-induced apoptosis was neither dependent on ROS nor on MAPK. Structure-activity relationship studies suggested that the thiol reacting effect of protoapigenone might be associated with an α, β-unsaturated ketone moiety in the structure of ring B.

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.

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 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.

S-glutathionyl-(chloro)hydroquinone reductases: a new class of glutathione transferases functioning as oxidoreductases

PubMed Central

Belchik, Sara M.; Xun, Luying

2011-01-01

Glutathione transferases (GSTs) are best known for transferring glutathione (GSH) to hydrophobic organic compounds, making the conjugates more soluble. However, the omega-class GSTs of animals and the lambda-class GSTs and dehydroascorbate reductases (DHARs) of plants have little or no activity for GSH transfer. Instead, they catalyze GSH-dependent oxidoreductions. The lambda-class GSTs reduce disulfide bonds, the DHARs reduce the disulfide bonds and dehydroascorbate, and the omega-class GSTs can reduce more substrates, including disulfide bonds, dehydroascorbate, and dimethylarsinate. Glutathionyl-(chloro)hydroquinone reductases (GS-HQRs) are the newest class of GSTs that mainly catalyze oxidoreductions. Besides the activities of the other three classes, GS-HQRs also reduce GS-hydroquinones, including GS-trichloro-p-hydroquinone, GS-dichloro-p-hydroquinone, GS-2-hydroxy-p-hydroquinone, and GS-p-hydroquinone. They are conserved and widely distributed in bacteria, fungi, protozoa, and plants, but not in animals. The four classes are phylogenetically more related to each other than to other GSTs, and they share a Cys-Pro motif at the GSH-binding site. Hydroquinones are metabolic intermediates of certain aromatic compounds. They can be auto-oxidized by O2 to benzoquinones, which spontaneously react with GSH to form GS-hydroquinones via Michael’s addition. GS-HQRs are expected to channel GS-hydroquinones, formed spontaneously or enzymatically, back to hydroquinones. When the released hydroquinones are intermediates of metabolic pathways, GS-HQRs play a maintenance role for the pathways. Further, the common presence of GS-HQRs in plants, green algae, cyanobacteria, and halobacteria suggest a beneficial role in the light-using organisms. PMID:21425927

Sulphur alters chromium (VI) toxicity in Solanum melongena seedlings: Role of sulphur assimilation and sulphur-containing antioxidants.

PubMed

Singh, Madhulika; Kushwaha, Bishwajit Kumar; Singh, Samiksha; Kumar, Vipin; Singh, Vijay Pratap; Prasad, Sheo Mohan

2017-03-01

The present study investigates modulation in hexavalent chromium [Cr(VI) 25 μM] toxicity by sulphur (S; 0.5, 1.0 and 1.5 mM S as low (LS), medium (MS) and high sulphur (HS), respectively) in Solanum melongena (eggplant) seedlings. Biomass accumulation (fresh and dry weights), photosynthetic pigments, photosynthetic oxygen evolution and S content were declined by Cr(VI) toxicity. Furthermore, fluorescence characteristics (JIP-test) were also affected by Cr(VI), but Cr(VI) toxicity on photosystem II photochemistry was ameliorated by HS treatment via reducing damaging effect on PS II reaction centre and its reduction side. Enhanced respiration, Cr content and oxidative biomarkers: superoxide radical, hydrogen peroxide, lipid peroxidation and membrane damage were observed under Cr(VI) stress. Though Cr(VI) enhanced adenosine triphasphate sulfurylase (ATPS) and o-acetylserine(thiol)lyase (OASTL), glutathione-S-transferase (GST), glutathione reductase (GR) and ascorbate peroxidase (APX) activity, and content of total glutathione, cysteine and NP-SH, however, their levels/activity were further enhanced by S being maximum with HS treatment. The results show that Cr(VI) toxicity does increase under LS treatment while HS protected Cr(VI)-induced damaging effects in brinjal seedlings. Under HS treatment, in mitigating Cr(VI) toxicity, S assimilation and its associated metabolites such as cysteine, glutathione and NP-SH play crucial role. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

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.

Increased 4-hydroxynonenal protein adducts in male GSTA4–4/PPAR-alpha double knockout mice enhance injury during early stages of alcoholic liver disease

USDA-ARS?s Scientific Manuscript database

To test the significance of lipid peroxidation in the development of alcoholic liver injury, an ethanol (EtOH) liquid diet was fed to male wild type 129/SvJ mice, and glutathione S-transferase A4-4 null (GSTA4-/-) mice for 40 d. GSTA4-/- mice were also crossed with peroxisome proliferator-activated ...

Functional Characterization and Expression of Molluscan Detoxification Enzymes and Transporters Involved in Dietary Allelochemical Resistance

DTIC Science & Technology

2008-06-01

gastropod Cvphoma gibbosum feeding on a variety of chemically defended gorgonian corals, and to identify those dietary natural products that act as...detoxification and transport-mediated resistance to dietary allelochemicals. The ovulid gastropod Cyphoma gibbosum is considered a trophic generalist, feeding...enzymatic activity of glutathione S-transferases from the generalist marine gastropod , Cyphoma gibbosum Abstract 74 Introduction 75 Methods 78 Results 86

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.

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.

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.

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

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.

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.

Cytoprotective Mechanisms Mediated by Polyphenols from Chilean Native Berries against Free Radical-Induced Damage on AGS Cells

PubMed Central

Theoduloz, Cristina; López-Alarcón, Camilo; Dorta, Eva

2017-01-01

The prevalence of cytoprotective mechanisms induced by polyphenols such as activation of intracellular antioxidant responses (ICM) and direct free radical scavenging was investigated in native Chilean species of strawberries, raspberries, and currants. Human gastric epithelial cells were co- and preincubated with polyphenolic-enriched extracts (PEEs) from Chilean raspberries (Rubus geoides), strawberries (Fragaria chiloensis ssp. chiloensis f. chiloensis), and currants (Ribes magellanicum) and challenged with peroxyl and hydroxyl radicals. Cellular protection was determined in terms of cell viability, glyoxalase I and glutathione s-transferases activities, and carboxymethyl lysine (CML) and malondialdehyde levels. Our results indicate that cytoprotection induced by ICM was the prevalent mechanism for Rubus geoides and F. chiloensis. This agreed with increased levels of glyoxalase I and glutathione S-transferase activities in cells preincubated with PEEs. ORAC index indicated that F. chiloensis was the most efficient peroxyl radical scavenger. Moreover, ICM mediated by F. chiloensis was effective in protecting cells from CML accumulation in contrast to the protective effects induced by free radical scavenging. Our results indicate that although both polyphenol-mediated mechanisms can exert protective effects, ICM was the most prevalent in AGS cells. These results suggest a potential use of these native berries as functional food. PMID:28553436

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.

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.

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.

Energetics of Glutathione Binding to Human Eukaryotic Elongation Factor 1 Gamma: Isothermal Titration Calorimetry and Molecular Dynamics Studies.

PubMed

Tshabalala, Thabiso N; Tomescu, Mihai-Silviu; Prior, Allan; Balakrishnan, Vijayakumar; Sayed, Yasien; Dirr, Heini W; Achilonu, Ikechukwu

2016-12-01

The energetics of ligand binding to human eukaryotic elongation factor 1 gamma (heEF1γ) was investigated using reduced glutathione (GSH), oxidised glutathione (GSSG), glutathione sulfonate and S-hexylglutathione as ligands. The experiments were conducted using isothermal titration calorimetry, and the findings were supported using computational studies. The data show that the binding of these ligands to heEF1γ is enthalpically favourable and entropically driven (except for the binding of GSSG). The full length heEF1γ binds GSSG with lower affinity (K d  = 115 μM), with more hydrogen-bond contacts (ΔH = -73.8 kJ/mol) and unfavourable entropy (-TΔS = 51.7 kJ/mol) compared to the glutathione transferase-like N-terminus domain of heEF1γ, which did not show preference to any specific ligand. Computational free binding energy calculations from the 10 ligand poses show that GSSG and GSH consistently bind heEF1γ, and that both ligands bind at the same site with a folded bioactive conformation. This study reveals the possibility that heEF1γ is a glutathione-binding protein.

Chronic toxicity of arsenic during Rhinella arenarum embryonic and larval development: Potential biomarkers of oxidative stress and antioxidant response.

PubMed

Mardirosian, Mariana Noelia; Lascano, Cecilia Inés; Bongiovanni, Guillermina Azucena; Venturino, Andrés

2017-06-01

The Argentinean autochthonous toad Rhinella arenarum was selected to study the chronic toxicity of arsenic (As) and the biochemical responses elicited by exposure to As in water during embryonic and larval development. Significant decreases in the total reactive antioxidant potential and in catalase activity were observed in individuals exposed chronically to sublethal concentrations of As, which is indicative of an oxidative stress situation. However, an antioxidant response was elicited during chronic exposure to As, as evidenced by the increase in endogenous reduced glutathione content and glutathione-related enzymatic activities such as glutathione S-transferase (GST) and glutathione reductase. This protective response might prevent a deeper decline in the antioxidant system and further oxidative damage. Alternatively, it might be linked to As conjugation with reduced glutathione for its excretion. Considering the sustained increase in GST activity and the decrease in the total antioxidant reactive potential observed, the authors propose them as good candidates to be used as biomarkers during As exposure. Interestingly, glutathione reductase activity was inhibited at a very low concentration of As considered safe for aquatic life. Environ Toxicol Chem 2017;36:1614-1621. © 2016 SETAC. © 2016 SETAC.

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 and its combination with GSTM1, and GSTT1 may be associated with bladder cancer susceptibility in the Iranian population. Further confirmation in large population-based studies is needed. Copyright © 2013 Elsevier Inc. All rights reserved.

H2O2 from the oxidative burst orchestrates the plant hypersensitive disease resistance response.

PubMed

Levine, A; Tenhaken, R; Dixon, R; Lamb, C

1994-11-18

Microbial elicitors or attempted infection with an avirulent pathogen strain causes the rapid production of reactive oxygen intermediates. We report here that H2O2 from this oxidative burst not only drives the cross-linking of cell wall structural proteins, but also functions as a local trigger of programmed death in challenged cells and as a diffusible signal for the induction in adjacent cells of genes encoding cellular protectants such as glutathione S-transferase and glutathione peroxidase. Thus, H2O2 from the oxidative burst plays a key role in the orchestration of a localized hypersensitive response during the expression of plant disease resistance.

Exogenous salicylic acid improves photosynthesis and growth through increase in ascorbate-glutathione metabolism and S assimilation in mustard under salt stress

PubMed Central

Nazar, Rahat; Umar, Shahid; Khan, Nafees A.

2015-01-01

Ascorbate (AsA)–glutathione (GSH) cycle metabolism has been regarded as the most important defense mechanism for the resistance of plants under stress. In this study the influence of salicylic acid (SA) was studied on ascorbate-glutathione pathway, S-assimilation, photosynthesis and growth of mustard (Brassica juncea L.) plants subjected to 100 mM NaCl. Treatment of SA (0.5 mM) alleviated the negative effects of salt stress and improved photosynthesis and growth through increase in enzymes of ascorbate-glutathione pathway which suggest that SA may participate in the redox balance under salt stress. The increase in leaf sulfur content through higher activity of ATP sulfurylase (ATPS) and serine acetyl transferase (SAT) by SA application was associated with the increased accumulation of glutathione (GSH) and lower levels of oxidative stress. These effects of SA were substantiated by the findings that application of SA-analog, 2,6, dichloro-isonicotinic acid (INA) and 1 mM GSH treatment produced similar results on rubisco, photosynthesis and growth of plants establishing that SA application alleviates the salt-induced decrease in photosynthesis mainly through inducing the enzyme activity of ascorbate-glutathione pathway and increased GSH production. Thus, SA/GSH could be a promising tool for alleviation of salt stress in mustard plants. PMID:25730495

Protective effects of pomegranate (Punica granatum) juice on testes against carbon tetrachloride intoxication in rats

PubMed Central

2014-01-01

Background Pomegranate fruit has been extensively used as a natural medicine in many cultures. The present study was aimed at evaluating the protective effects of pomegranate (Punica granatum) juice against carbon tetrachloride (CCl4)-induced oxidative stress and testes injury in adult Wistar rats. Methods Twenty eight Wistar albino male rats were divided equally into 4 groups for the assessment of protective potential of pomegranate juice. Rats of group I (control) received only vehicles and had free access to food and water. Rats of groups II and IV were treated with CCl4 (2 ml/kg bwt) via the intraperitoneal route once a week for ten weeks. The pomegranate juice was supplemented via drinking water 2 weeks before and concurrent with CCl4 treatment to group IV. Group III was supplemented with pomegranate juice for twelve weeks. The protective effects of pomegranate on serum sex hormones, oxidative markers, activities of antioxidant enzymes and histopathology of testes were determined in CCl4-induced reproductive toxicity in rats. Results Pomegranate juice showed significant elevation in testosterone, luteinizing hormone (LH) and follicle stimulating hormone (FSH) those depleted by the injection of CCl4. Activity levels of endogenous testesticular antioxidant enzymes; superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione-S-transferase (GST) and glutathione reductase (GR) and glutathione (GSH) contents were increased while lipid peroxidation (LPO) and nitric oxide (NO) were decreased with pomegranate juice. Moreover, degeneration of germ and Leydig cells along with deformities in spermatogenesis induced after CCl4 injections were restored with the treatment of pomegranate juice. Conclusion The results clearly demonstrated that pomegranate juice augments the antioxidant defense mechanism against carbon tetrachloride-induced reproductive toxicity and provides evidence that it may have a therapeutic role in free radical mediated diseases. PMID:24884677

Modulation of carbon tetrachloride-induced nephrotoxicity in rats by n-hexane extract of Sonchus asper.

PubMed

Khan, Rahmat Ali; Khan, Muhammad Rashid; Shah, Naseer Ali; Sahreen, Sumaira; Siddiq, Pakiza

2015-10-01

Sonchus asper is traditionally used in the treatment of renal dysfunction. In the present study, protective effects of S. asper against carbon tetrachloride (CCl4)-induced nephrotoxicity of rats were determined. In this study, 24 male albino rats (190-200 g) were equally divided into four groups. Group I (control group) was given saline (1 ml/kg body weight (b.w.), 0.85% NaCl) and dimethyl sulfoxide (1 ml/kg b.w.); group II was treated with CCl4 (1 ml/kg b.w. intraperitoneally); groups III and IV were administered with CCl4 and after 48 h with S. asper n-hexane extract (SHE; 100 and 200 mg/kg b.w.). All the treatments were given twice a week for 4 weeks. The results revealed that CCl4-induced oxidative stress as evidenced by the significant depletion of antioxidant enzymes, namely, superoxide dismutase, catalase, peroxidase, glutathione-S-transferase, glutathione peroxidase, glutathione reductase, and glutathione contents, while increased lipid peroxidation (thiobarbituric acid-reactive substances contents). Administration of SHE significantly ameliorated (p < 0.01) the activity of antioxidant enzymes and reduced lipid peroxides. Coadministration revealed that S. asper extract can protect the kidney against CCl4-mediated oxidative damage by restoring the activity of antioxidant enzyme, due to the presence of plant bioactive constituents. © The Author(s) 2013.

Pyrethroid Resistance in Malaysian Populations of Dengue Vector Aedes aegypti Is Mediated by CYP9 Family of Cytochrome P450 Genes

PubMed Central

Ishak, Intan H.; Kamgang, Basile; Ibrahim, Sulaiman S.; Riveron, Jacob M.; Irving, Helen

2017-01-01

Background Dengue control and prevention rely heavily on insecticide-based interventions. However, insecticide resistance in the dengue vector Aedes aegypti, threatens the continued effectiveness of these tools. The molecular basis of the resistance remains uncharacterised in many endemic countries including Malaysia, preventing the design of evidence-based resistance management. Here, we investigated the underlying molecular basis of multiple insecticide resistance in Ae. aegypti populations across Malaysia detecting the major genes driving the metabolic resistance. Methodology/Principal Findings Genome-wide microarray-based transcription analysis was carried out to detect the genes associated with metabolic resistance in these populations. Comparisons of the susceptible New Orleans strain to three non-exposed multiple insecticide resistant field strains; Penang, Kuala Lumpur and Kota Bharu detected 2605, 1480 and 425 differentially expressed transcripts respectively (fold-change>2 and p-value ≤ 0.05). 204 genes were commonly over-expressed with monooxygenase P450 genes (CYP9J27, CYP6CB1, CYP9J26 and CYP9M4) consistently the most up-regulated detoxification genes in all populations, indicating that they possibly play an important role in the resistance. In addition, glutathione S-transferases, carboxylesterases and other gene families commonly associated with insecticide resistance were also over-expressed. Gene Ontology (GO) enrichment analysis indicated an over-representation of GO terms linked to resistance such as monooxygenases, carboxylesterases, glutathione S-transferases and heme-binding. Polymorphism analysis of CYP9J27 sequences revealed a high level of polymorphism (except in Joho Bharu), suggesting a limited directional selection on this gene. In silico analysis of CYP9J27 activity through modelling and docking simulations suggested that this gene is involved in the multiple resistance in Malaysian populations as it is predicted to metabolise pyrethroids, DDT and bendiocarb. Conclusion/significance The predominant over-expression of cytochrome P450s suggests that synergist-based (PBO) control tools could be utilised to improve control of this major dengue vector across Malaysia. PMID:28114328

[Study of enzymes of xenobiotic metabolism in the evaluation of quality of protein-containing wheat germ flakes and wallpaper flour].

PubMed

Martinchuk, A N; E En Gyn; Safronova, A M; Peskova, E V

1991-01-01

Intake of wheat upholstery meal by growing rats was attended by a sharp decrease in the content and activity of xenobiotic metabolism enzymes in the hepatic microsomes, that was caused by the low biological value of the meal proteins. Hepatic microsomes of the rats that were fed with wheat germ flakes showed increased specific content of cytochromes P-450 and b5, but the total blood protein content per 100 g of body mass was lower than during casein consumption. No significant changes were detected in hydroxylation rate of benz(a)pyrene, aniline and ethylmorphine. During consumption of wheat germ flakes induction of UDP-glucuronide-transferase was detected in hepatic microsomes. Wheat germ flakes induced a 5-fold increase of Se-dependent glutathione peroxidase activity. Wheat germ flakes produced no significant effect on glutathione-S-aryltransferase and glutathione reductase activity.

Antidiabetic effect of Scoparia dulcis: effect on lipid peroxidation in streptozotocin diabetes.

PubMed

Pari, L; Latha, M

2005-03-01

Oxidative damage has been suggested to be a contributory factor in the development and complications of diabetes. The antioxidant effect of an aqueous extract of Scoparia dulcis, an indigenous plant used in Ayurvedic medicine in India was studied in rats with streptozotocin-induced diabetes. Oral administration of Scoparia dulcis plant extract (SPEt) (200 mg/kg body weight) for 3 weeks resulted in a significant reduction in blood glucose and an increase in plasma insulin. The aqueous extract also resulted in decreased free radical formation in tissues (liver and kidney) studied. The decrease in thiobarbituric acid reactive substances (TBARS) and hydroperoxides (HPX) and increase in the activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), reduced glutathione (GSH) and glutathione-S-transferase (GST) clearly show the antioxidant properties of SPEt in addition to its antidiabetic effect. The effect of SPEt at 200 mg/kg body weight was better than glibenclamide, a reference drug.

Effect of Tridax procumbens on liver antioxidant defense system during lipopolysaccharide-induced hepatitis in D-galactosamine sensitised rats.

PubMed

Ravikumar, Vilwanathan; Shivashangari, Kanchi Subramanian; Devaki, Thiruvengadam

2005-01-01

The present study was carried out to assess the effect of chloroform insoluble fraction of ethanolic extract of Tridax procumbens (TP) against D-Galactosamine/Lipopolysaccharide (D-GalN/LPS)-induced hepatitis in rats. Induction of rats with D-GalN/LPS (300 mg/kg body weight/30 microg/kg body weight) led to a marked increase in lipid peroxidation as measured by thiobarbituric acid reactive substances (TBARS) in liver. Further there was a decline in the activities of enzymic antioxidants such as superoxide dismutase, catalase, glutathione peroxidase, glutathione s-transferase and the levels of non-enzymic antioxidants namely reduced glutathione, vitamin C and vitamin E. These biochemical alterations were normalised upon pretreatment with TP extract. Thus, the above results suggest that TP (300 mg/kg body weight orally for 10 days) is very effective in allievating the D-GalN/LPS-induced oxidative stress suggesting its antioxidant property.

Fly ash leachate induces oxidative stress in freshwater fish Channa punctata (Bloch).

PubMed

Ali, M; Parvez, S; Pandey, S; Atif, F; Kaur, M; Rehman, H; Raisuddin, S

2004-09-01

Oxidative stress inducing potential of fly ash leachate (FAL) was studied in a freshwater fish, Channa punctata (Bloch). Fish were exposed to fly ash leachate for 24 h and lipid peroxidation (LPO) was studied as a marker of oxidative stress. Catalase (CAT), glutathione S-transferase (GST) activities and levels of reduced glutathione (GSH) were also estimated in the exposed fish. FAL (1 ml/l) induced LPO in all the organs and most prominent response was in the gill. It also caused induction of enzymes and glutathione. Liver showed highest level of induction of enzyme activities. The results of this study demonstrate that fly ash constituents have potential to induce oxidative stress in fish and gills are the most vulnerable organs. It is also suggested that in case of exposure to FAL, along with LPO antioxidant defense is also activated to counteract the reactive oxygen species (ROS) at least partly in the initial stages of exposure.

Role of geraniol against lead acetate-mediated hepatic damage and their interaction with liver carboxylesterase activity in rats.

PubMed

Ozkaya, Ahmet; Sahin, Zafer; Kuzu, Muslum; Saglam, Yavuz Selim; Ozkaraca, Mustafa; Uckun, Mirac; Yologlu, Ertan; Comakli, Veysel; Demirdag, Ramazan; Yologlu, Semra

2018-02-01

In this study, the effect of geraniol (50 mg/kg for 30 d), a natural antioxidant and repellent/antifeedant monoterpene, in a rat model of lead acetate-induced (500 ppm for 30 d) liver damage was evaluated. Hepatic malondialdehyde increased in the lead acetate group. Reduced glutathione unchanged, but glutathione S-transferase, glutathione reductase, as well as carboxylesterase activities decreased in geraniol, lead acetate and geraniol + lead acetate groups. 8-OhDG immunoreactivity, mononuclear cell infiltrations and hepatic lead concentration were lower in the geraniol + lead acetate group than the lead acetate group. Serum aspartate aminotransferase and alanine aminotransferase activities increased in the Pb acetate group. In conclusion, lead acetate causes oxidative and toxic damage in the liver and this effect can reduce with geraniol treatment. However, we first observed that lead acetate, as well as geraniol, can affect liver carboxylesterase activity.

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 reserved.

Antioxidative stress responses in the floating macrophyte Lemna minor L. with cylindrospermopsin exposure.

PubMed

Flores-Rojas, Nelida Cecilia; Esterhuizen-Londt, Maranda; Pflugmacher, Stephan

2015-12-01

Cylindrospermopsin toxicity and oxidative stress have been examined in aquatic animals, however, only a few studies with aquatic plants have been conducted focusing on the potential for bioaccumulation of cylindrospermopsin. The oxidative stress effects caused by cylindrospermopsin on macrophytes have not yet been specifically studied. The oxidative stress response of Lemna minor L. with exposure to cylindrospermopsin, was therefore tested in this study. The hydrogen peroxide concentration together with the activities of the antioxidant enzymes (catalase, peroxidase, glutathione reductase and glutathione S-transferase) were determined after 24h (hours) of exposure to varying concentrations (0.025, 0.25, 2.5 and 25μg/L) of cylindrospermopsin. Responses with longer exposure periods (48, 96, 168h) were tested only with exposure to 2.5 and 25μg/L cylindrospermopsin. Additionally, the content of the carotenoids was determined as a possible non-enzymatic antioxidant defence mechanism against cylindrospermopsin. The levels of hydrogen peroxide increased after 24h even at the lowest cylindrospermopsin exposure concentrations. Catalase showed the most representative antioxidant response observed after 24h and maintained its activity throughout the experiment. Catalase activity corresponded with the contents of hydrogen peroxide at 2.5 and 25μg/L cylindrospermopsin. The data suggest that glutathione S-transferase, glutathione reductase and the carotenoid content act together with catalase but are more sensitive to higher concentrations of cylindrospermopsin and after a longer exposure period (168h). The results indicate that cylindrospermopsin promotes oxidative stress in L. minor at concentrations of 2.5 and 25μg/L. However, L. minor has sufficient defence mechanisms in place against this cyanobacterial toxin. Even though L. minor exhibits the potential to managing and control cylindrospermopsin contamination in aquatic systems, further studies in tolerance limits to cylindrospermopsin, uptake and experiments with prolonged exposure periods of more than 7 days are required. Copyright © 2015 Elsevier B.V. All rights reserved.

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

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.

Reviewing Hit Discovery Literature for Difficult Targets: Glutathione Transferase Omega-1 as an Example.

PubMed

Xie, Yiyue; Dahlin, Jayme L; Oakley, Aaron J; Casarotto, Marco G; Board, Philip G; Baell, Jonathan B

2018-05-10

Early stage drug discovery reporting on relatively new or difficult targets is often associated with insufficient hit triage. Literature reviews of such targets seldom delve into the detail required to critically analyze the associated screening hits reported. Here we take the enzyme glutathione transferase omega-1 (GSTO1-1) as an example of a relatively difficult target and review the associated literature involving small-molecule inhibitors. As part of this process we deliberately pay closer-than-usual attention to assay interference and hit quality aspects. We believe this Perspective will be a useful guide for future development of GSTO1-1 inhibitors, as well serving as a template for future review formats of new or difficult targets.

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.

Glutathione oxidation in response to intracellular H2O2: Key but overlapping roles for dehydroascorbate reductases.

PubMed

Rahantaniaina, Marie-Sylviane; Li, Shengchun; Chatel-Innocenti, Gilles; Tuzet, Andrée; Mhamdi, Amna; Vanacker, Hélène; Noctor, Graham

2017-08-03

Glutathione is a pivotal molecule in oxidative stress, during which it is potentially oxidized by several pathways linked to H 2 O 2 detoxification. We have investigated the response and functional importance of 3 potential routes for glutathione oxidation pathways mediated by glutathione S-transferases (GST), glutaredoxin-dependent peroxiredoxins (PRXII), and dehydroascorbate reductases (DHAR) in Arabidopsis during oxidative stress. Loss-of-function gstU8, gstU24, gstF8, prxIIE and prxIIF mutants as well as double gstU8 gstU24, gstU8 gstF8, gstU24 gstF8, prxIIE prxIIF mutants were obtained. No mutant lines showed marked changes in their phenotype and glutathione profiles in comparison to the wild-type plants in either optimal conditions or oxidative stress triggered by catalase inhibition. By contrast, multiple loss of DHAR functions markedly decreased glutathione oxidation triggered by catalase deficiency. To assess whether this effect was mediated directly by loss of DHAR enzyme activity, or more indirectly by upregulation of other enzymes involved in glutathione and ascorbate recycling, we measured expression of glutathione reductase (GR) and expression and activity of monodehydroascorbate reductases (MDHAR). No evidence was obtained that either GRs or MDHARs were upregulated in plants lacking DHAR function. Hence, interplay between different DHARs appears to be necessary to couple ascorbate and glutathione pools and to allow glutathione-related signaling during enhanced H 2 O 2 metabolism.

Rice protein improves oxidative stress by regulating glutathione metabolism and attenuating oxidative damage to lipids and proteins in rats.

PubMed

Yang, Lin; Chen, Jia-Hou; Xu, Tong; Zhou, Ai-Shen; Yang, Hong-Kun

2012-10-05

To evaluate the effects of rice protein (RP) on glutathione metabolism and oxidative damage. Seven-week-old male Wistar rats were fed diets containing casein and RP without cholesterol for 3weeks. Plasma and liver lipid levels, hepatic accumulation of total glutathione (T-GSH), oxidized glutathione (GSSG), reduced glutathione (GSH), malondialdehyde (MDA) and protein carbonyl (PCO) were measured. In the liver, the total antioxidative capacity (T-AOC), mRNA levels of glutamate cysteine ligase catalytic subunit (GCLC) and glutamate cysteine ligase modulatory subunit (GCLM), and the activities of hepatic catalase (CAT), total superoxide dismutase (T-SOD), γ-glutamylcysteine synthetase (γ-GCS), glutathione S-transferase (GST), glutathione reductase (GR) and glutathione peroxidase (GSHPx) were also measured. T-AOC, GCLC and GCLM mRNA levels, antioxidative enzyme activities (T-SOD and CAT) and glutathione metabolism related enzyme activities (γ-GCS, GST, GR and GSHPx) were effectively stimulated by RP feeding compared to casein, and RP significantly reduced the hepatic accumulation of MDA and PCO in rats. These results indicate that lipid-lowering activity was induced by RP feeding. The present study demonstrates that RP improves oxidative stress primarily through enzymatic and non-enzymatic antioxidative defense mechanisms, reflected by enhancing the antioxidative status and attenuating the oxidative damage to lipids and proteins. These results suggest that RP can prevent hyperlipidemia in part through modifying glutathione metabolism, and sulfur amino acids may be the main modulator of this antioxidative mechanism. Copyright © 2012 Elsevier Inc. All rights reserved.

GSTP1 Loss Results in Accumulation of Oxidative DNA Base Damage and Promotes Prostate Cancer Cell Survival Following Exposure to Protracted Oxidative Stress

PubMed Central

Mian, Omar Y.; Khattab, Mohamed H.; Hedayati, Mohammad; Coulter, Jonathan; Abubaker-Sharif, Budri; Schwaninger, Julie M.; Veeraswamy, Ravi K.; Brooks, James D.; Hopkins, Lisa; Shinohara, Debika Biswal; Cornblatt, Brian; Nelson, William G.; Yegnasubramanian, Srinivasan; DeWeese, Theodore L.

2016-01-01

BACKGROUND Epigenetic silencing of glutathione S-transferase π (GSTP1) is a hallmark of transformation from normal prostatic epithelium to adenocarcinoma of the prostate. The functional significance of this loss is incompletely understood. The present study explores the effects of restored GSTP1 expression on glutathione levels, accumulation of oxidative DNA damage, and prostate cancer cell survival following oxidative stress induced by protracted, low dose rate ionizing radiation (LDR). METHODS GSTP1 protein expression was stably restored in LNCaP prostate cancer cells. The effect of GSTP1 restoration on protracted LDR-induced oxidative DNA damage was measured by GC-MS quantitation of modified bases. Reduced and oxidized glutathione levels were measured in control and GSTP1 expressing populations. Clonogenic survival studies of GSTP1-transfected LNCaP cells after exposure to protracted LDR were performed. Global gene expression profiling and pathway analysis were performed. RESULTS GSTP1 expressing cells accumulated less oxidized DNA base damage and exhibited decreased survival compared to control LNCaP-Neo cells following oxidative injury induced by protracted LDR. Restoration of GSTP1 expression resulted in changes in modified glutathione levels that correlated with GSTP1 protein levels in response to protracted LDR-induced oxidative stress. Survival differences were not attributable to depletion of cellular glutathione stores. Gene expression profiling and pathway analysis following GSTP1 restoration suggests this protein plays a key role in regulating prostate cancer cell survival. CONCLUSIONS The ubiquitous epigenetic silencing of GSTP1 in prostate cancer results in enhanced survival and accumulation of potentially promutagenic DNA adducts following exposure of cells to protracted oxidative injury suggesting a protective, anti-neoplastic function of GSTP1. The present work provides mechanistic backing to the tumor suppressor function of GSTP1 and its role in prostate carcinogenesis. PMID:26447830

Microsomal detoxification enzymes in yam bean [Pachyrhizus erosus (L.) urban].

PubMed

Belford, Ebenezer J D; Dörfler, Ulrike; Stampfl, Andreas; Schröder, Peter

2004-01-01

Cytochrome P450s and glutathione-S-transferases (GSTs) constitute two of the largest groups of enzyme families that are responsible for detoxification of exogenous molecules in plants. Their activities differ from plant to plant with respect to metabolism and substrate specificity which is one of the reasons for herbicide selectivity. In the tuber forming yam bean, the legume Pachyrhizus erosus, their activities at the microsomal level were investigated to determine the detoxification status of the plant. The breakdown of the herbicide isoproturon (IPU) to two distinct metabolites, 1-OH-IPU and monodesmethyl-IPU, was demonstrated. GST activity was determined with model substrates, but also by the catalysed formation of the fluorescent glutathione bimane conjugate. This study demonstrates for the first time microsomal detoxification activity in Pachyrhizus and the fluorescence image description of microsomal GST catalysed reaction in a legume.

Antioxidant and drug detoxification potential of aqueous extract of Annona senegalensis leaves in carbon tetrachloride-induced hepatocellular damage.

PubMed

Ajboye, Taofeek O; Yakubu, Musa T; Salau, Amadu K; Oladiji, Adenike T; Akanji, Musbau A; Okogun, Joseph I

2010-12-01

 Despite the myriad uses of Annona senegalensis Pers. (Annonaceae) leaves in folklore medicine of Nigeria, the basis is yet to be substantiated by scientific investigations.  To investigate the antioxidant (in vitro and in vivo) and drug detoxification potential of aqueous extract of A. senegalensis leaves in CCl₄-induced hepatocellular damage.  In vitro antioxidant activity of the aqueous extract of A. senegalensis leaves was evaluated using 2,2-diphenyl-1-picrylhydrazyl (DPPH), H₂O₂, superoxide ion, 2,2'-azinobis-(3-ethylbenzthiazoline-6-sulfonate) (ABTS) and ferric ion models while in vivo antioxidant and drug detoxification activities of the extract at 100, 200, and 400 mg/kg body weight were done by assaying the levels of enzymic and non-enzymic indices in CCl₄-induced hepatocellular damage.  The extract at 1 mg/mL scavenged DPPH, H₂O₂, superoxide ion, and ABTS radicals, whereas ferric ion was significantly (P <0.05) reduced. The levels of alkaline and acid phosphatases, alanine and aspartate aminotransferases, superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, glucose-6-phosphate dehydrogenase, reduced glutathione, vitamins C and E, glutathione S-transferase, nicotinamide adenine dinucleotide (reduced):Quinone oxidoreductase, uridyl diphosphoglucuronyl transferase, malondialdehyde, and lipid hydroperoxide that decreased in CCl₄ treated animals were significantly attenuated by the extract in a manner similar to the animals treated with the reference drug.  The ability of the aqueous extract of A. senegalensis leaves to scavenge free radicals in vitro and reversal of CCl₄-induced hepatocellular damage in rats suggest antioxidant and drug detoxification activities. Overall, this study has justified the rationale behind some of the medicinal uses of the plant in folklore medicine of Nigeria.

Effects of long-term administration of aspartame on biochemical indices, lipid profile and redox status of cellular system of male rats.

PubMed

Adaramoye, Oluwatosin A; Akanni, Olubukola O

2016-01-01

Aspartame (N-L-α-aspartyl-L-phenylalanine-1-methyl ester) (ASP) is a synthetic sweetener used in foods and its safety remains controversial. The study was designed to investigate the effects of long-term administration of aspartame on redox status, lipid profile and biochemical indices in tissues of male Wistar rats. Rats were assigned into four groups and given distilled water (control), aspartame at doses of 15 mg/kg (ASP 1), 35 mg/kg (ASP 2) and 70 mg/kg (ASP 3) daily by oral gavage for consecutive 9 weeks. Administration of ASP 2 and ASP 3 significantly increased the weight of liver and brain, and relative weight of liver of rats. Lipid peroxidation products significantly increased in the kidney, liver and brain of rats at all doses of ASP with concomitant depletion of antioxidant parameters, viz. glutathione-s-transferase, glutathione peroxidase, superoxide dismutase, catalase and reduced glutathione. Furthermore, ASP 2 and ASP 3 significantly increased the levels of gamma glutamyl transferase by 70% and 85%; alanine aminotransferase by 66% and 117%; aspartate aminotransferase by 21% and 48%; urea by 72% and 58% and conjugated bilirubin by 63% and 64%, respectively. Also, ASP 2 and ASP 3 significantly increased the levels of total cholesterol, triglycerides and low-density lipoprotein cholesterol in the rats. Histological findings showed that ASP 2 and ASP 3 caused cyto-architectural changes such as degeneration, monocytes infiltration and necrotic lesions in brain, kidney and liver of rats. Aspartame may induce redox and lipid imbalance in rats via mechanism that involves oxidative stress and depletion of glutathione-dependent system.

Zingiber officinale and 6-gingerol alleviate liver and kidney dysfunctions and oxidative stress induced by mercuric chloride in male rats: A protective approach.

PubMed

Joshi, Deepmala; Srivastav, Sunil Kumar; Belemkar, Sateesh; Dixit, Vaibhav A

2017-07-01

Mercury toxicity is an emerging problem in the world as its concentration is rising continuously due to increased industrial, medicinal and domestic uses. Exposure to mercury represents a serious challenge to humans and other living biomes. The aim of the present study was to assess the protective effect of natural products as Zingiber officinale extract and its active compound (6-gingerol) against mercuric chloride-induced hepatorenal toxicity and oxidative stress in male rats. Male Sprague-Dawley rats (150±10g, n=6 per group) were administered HgCl 2 (12μmol/kg, ip; once only) the treatment of Zingiber officinale Rosc. extract (ZO: 125mg/kg, po) and 6-gingerol (GG: 50mg/kg, po) for three days after 24h of HgCl 2 administration. Acute HgCl 2 administration altered various biochemical parameters, including transaminases, alkaline phosphatase, lactate dehydrogenase, bilirubin, gamma-glutamyl transferase, triglycerides and cholesterol, urea, creatinine, uric acid and blood urea nitrogen contents with a concomitant decline in protein and albumin concentration in serum. In addition, a significant rise in lipid peroxidation level with concomitant decrease in reduced glutathione content and the antioxidant enzymes activities of superoxide dismutase, catalase, glutathione reductase, glutathione peroxidase and glutathione-S-transferase after acute HgCl 2 exposure. Results of the present investigation clearly showed that both treatments as Zingiber officinale extract and 6-gingerol provide protection against acute mercuric chloride-intoxication by preventing oxidative degradation of a biological membrane from metal mediated free radical attacks. Biochemical data were well supported by histopathological findings. In conclusion, natural products may be an ideal choice against oxidative damage induced by mercury poisoning. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Response of antioxidant enzymes in Nicotiana tabacum clones during phytoextraction of heavy metals.

PubMed

Lyubenova, Lyudmila; Nehnevajova, Erika; Herzig, Rolf; Schröder, Peter

2009-07-01

Tobacco, Nicotiana tabacum, is a widely used model plant for growth on heavy-metal-contaminated sites. Its high biomass and deep rooting system make it interesting for phytoextraction. In the present study, we investigated the antioxidative activities and glutathione-dependent enzymes of different tobacco clones optimized for better Cd and Zn accumulation in order to characterize their performance in the field. The improved heavy metal resistance also makes the investigated tobacco clones interesting for understanding the plant defense enzyme system in general. Freshly harvested plant material (N. tabacum leaves) was used to investigate the antioxidative cascade in plants grown on heavy metal contaminated sites with and without amendments of different ammonium nitrate and ammonium sulfate fertilizers. Plants were grown on heavily polluted soils in north-east Switzerland. Leaves were harvested at the field site and directly deep frozen in liquid N(2). Studies were concentrated on the antioxidative enzymes of the Halliwell-Asada cycle, and spectrophotometric measurements of catalase (CAT, EC 1.11.1.6), ascorbate peroxidase (APX, EC 1.11.1.11), superoxide dismutase (SOD, EC 1.15.1.1), glutathione peroxidase (GPX, EC 1.11.1.9), glutathione reductase (GR, EC 1.6.4.2), glutathione S-transferase (GST, EC 2.5.1.18) were performed. We tried to explain the relationship between fertilizer amendments and the activity of the enzymatic defense systems. When tobacco (N. tabacum) plants originating from different mutants were grown under field conditions with varying fertilizer application, the uptake of cadmium and zinc from soil increased with increasing biomass. Depending on Cd and Zn uptake, several antioxidant enzymes showed significantly different activities. Whereas SOD and CAT were usually elevated, several other enzymes, and isoforms of GST were strongly inhibited. Heavy metal uptake represents severe stress to plants, and specific antioxidative enzymes are induced at the cost of more general reactions of the Halliwell-Asada cycle. In well-supplied plants, the glutathione level remains more or less unchanged. The lack of certain glutathione S-transferases upon exposure to heavy metals might be problematic in cases when organic pollutants coincide with heavy metal pollution. When planning phytoremediation of sites, mixed pollution scenarios have to be foreseen and plants should be selected according to both, their stress resistance and hyperaccumulative capacity.

Crystal Structure of Saccharomyces cerevisiae ECM4, a Xi-Class Glutathione Transferase that Reacts with Glutathionyl-(hydro)quinones

PubMed Central

Schwartz, Mathieu; Didierjean, Claude; Hecker, Arnaud; Girardet, Jean-Michel; Morel-Rouhier, Mélanie; Gelhaye, Eric; Favier, Frédérique

2016-01-01

Glutathionyl-hydroquinone reductases (GHRs) belong to the recently characterized Xi-class of glutathione transferases (GSTXs) according to unique structural properties and are present in all but animal kingdoms. The GHR ScECM4 from the yeast Saccharomyces cerevisiae has been studied since 1997 when it was found to be potentially involved in cell-wall biosynthesis. Up to now and in spite of biological studies made on this enzyme, its physiological role remains challenging. The work here reports its crystallographic study. In addition to exhibiting the general GSTX structural features, ScECM4 shows extensions including a huge loop which contributes to the quaternary assembly. These structural extensions are probably specific to Saccharomycetaceae. Soaking of ScECM4 crystals with GS-menadione results in a structure where glutathione forms a mixed disulfide bond with the cysteine 46. Solution studies confirm that ScECM4 has reductase activity for GS-menadione in presence of glutathione. Moreover, the high resolution structures allowed us to propose new roles of conserved residues of the active site to assist the cysteine 46 during the catalytic act. PMID:27736955

The antitumour activity of alkylating agents is not correlated with the levels of glutathione, glutathione transferase and O6-alkylguanine-DNA-alkyltransferase of human tumour xenografts. EORTC SPG and PAMM Groups.

PubMed

D'Incalci, M; Bonfanti, M; Pifferi, A; Mascellani, E; Tagliabue, G; Berger, D; Fiebig, H H

1998-10-01

Twenty-three human xenografts, including five colon, five gastric, nine lung (three small cell lung cancer) and four breast carcinomas, were investigated for their sensitivity to nitrosoureas, dacarbazine (DTIC), cyclophosphamide (CTX) and cisplatin (DDP). In 12 cases, at least one of the drugs produced complete or partial remission, in 2, a minor regression was observed and in the other 9, treatment was ineffective. The level of sensitivity to each drug, using a score from 1 to 5, was correlated to three biochemical parameters reported to be involved in resistance to alkylating agents: glutathione (GSH), glutathione transferase (GST) and O6-alkylguanine-DNA-alkyltransferase (AGT). A wide variability was found in these parameters in the xenografts investigated. No correlation was found between any of the three parameters and sensitivity to the drugs used or between sensitivity to one drug and to any of the other drugs tested. These results illustrate the complexity of the question of resistance to alkylating agents and indicate that, at least in xenografts, the biochemical parameters examined are not predictive of response to alkylating agents.

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.

A Txnrd1-dependent metabolic switch alters hepatic lipogenesis, glycogen storage, and detoxification

PubMed Central

Iverson, Sonya V.; Eriksson, Sofi; Xu, Jianqiang; Prigge, Justin R.; Talago, Emily A.; Meade, Tesia A.; Meade, Erin S.; Capecchi, Mario R.; Arnér, Elias S.J.; Schmidt, Edward E.

2013-01-01

Besides helping to maintain a reducing intracellular environment, the thioredoxin (Trx) system impacts bioenergetics and drug-metabolism. We show that hepatocyte-specific disruption of Txnrd1, encoding Trx reductase-1 (TrxR1), causes a metabolic switch in which lipogenic genes are repressed and periportal hepatocytes become engorged with glycogen. These livers also overexpress machinery for biosynthesis of glutathione and conversion of glycogen into UDP-glucuronate; they stockpile glutathione-S-transferases and UDP-glucuronyl-transferases; and they overexpress xenobiotic exporters. This realigned metabolic profile suggested that the mutant hepatocytes might be preconditioned to more effectively detoxify certain xenobiotic challenges. Hepatocytes convert the pro-toxin acetaminophen (APAP, paracetamol) into cytotoxic N-acetyl-p-benzoquinone imine (NAPQI). APAP defenses include glucuronidation of APAP or glutathionylation of NAPQI, allowing removal by xenobiotic exporters. We found that NAPQI directly inactivates TrxR1, yet Txnrd1-null livers were resistant to APAP-induced hepatotoxicity. Txnrd1-null livers did not have more effective gene expression responses to APAP challenge; however their constitutive metabolic state supported more robust GSH biosynthesis-, glutathionylation-, and glucuronidation-systems. Following APAP challenge, this effectively sustained the GSH system and attenuated damage. PMID:23743293

Brassinosteroids play a critical role in the regulation of pesticide metabolism in crop plants

PubMed Central

Zhou, Yanhong; Xia, Xiaojian; Yu, Gaobo; Wang, Jitao; Wu, Jingxue; Wang, Mengmeng; Yang, Youxin; Shi, Kai; Yu, Yunlong; Chen, Zhixiang; Gan, Jay; Yu, Jingquan

2015-01-01

Pesticide residues in agricultural produce pose a threat to human health worldwide. Although the detoxification mechanisms for xenobiotics have been extensively studied in mammalian cells, information about the regulation network in plants remains elusive. Here we show that brassinosteroids (BRs), a class of natural plant hormones, decreased residues of common organophosphorus, organochlorine and carbamate pesticides by 30–70% on tomato, rice, tea, broccoli, cucumber, strawberry, and other plants when treated externally. Genome-wide microarray analysis showed that fungicide chlorothalonil (CHT) and BR co-upregulated 301 genes, including a set of detoxifying genes encoding cytochrome P450, oxidoreductase, hydrolase and transferase in tomato plants. The level of BRs was closely related to the respiratory burst oxidase 1 (RBOH1)-encoded NADPH oxides-dependent H2O2 production, glutathione biosynthesis and the redox homeostasis, and the activity of glutathione S-transferase (GST). Gene silencing treatments showed that BRs decreased pesticide residues in plants likely by promoting their metabolism through a signaling pathway involving BRs-induced H2O2 production and cellular redox change. Our study provided a novel approach for minimizing pesticide residues in crops by exploiting plants' own detoxification mechanisms. PMID:25761674

GSTP1 Polymorphisms and their Association with Glutathione Transferase and Peroxidase Activities in Patients with Motor Neuron Disease.

PubMed

Gajewska, Beata; Kaźmierczak, Beata; Kuźma-Kozakiewicz, Magdalena; Jamrozik, Zygmunt; Barańczyk-Kuźma, Anna

2015-01-01

Glutathione S-transferase pi (GSTP1) is a crucial enzyme in detoxification of electrophilic compounds and organic peroxides. Together with Se-dependent glutathione peroxidase (Se-GSHPx) it protects cells against oxidative stress which may be a primary factor implicated in motor neuron disease (MND) pathogenesis. We investigated GSTP1 polymorphisms and their relationship with GST and Se-GSTPx activities in a cohort of Polish patients with MND. Results were correlated with clinical phenotypes. The frequency of genetic variants for GSTP1 exon 5 (I105V) and exon 6 (A114V) was studied in 104 patients and 100 healthy controls using real-time polymerase chain reaction. GST transferase activity was determined in serum with 1-chloro-2,4-dinitrobenzene, its peroxidase activity with cumene hydroperoxide, and Se-GSHPx activity with hydrogen peroxide. There were no differences in the prevalence of GSTP1 polymorphism I105V and A114V between MND and controls, however the occurrence of CT variant in codon 114 was associated with a higher risk for MND. GSTP1 polymorphisms were less frequent in classic ALS than in progressive bulbar palsy. In classic ALS C* (heterozygous I /V and A /V) all studied activities were significantly lower than in classic ALS A* (homozygous I /I and A/A). GST peroxidase activity and Se-GSHPx activity were lower in classic ALS C* than in control C*, but in classic ALS A* Se-GSHPx activity was significantly higher than in control A*. It can be concluded that the presence of GSTP1 A114V but not I105V variant increases the risk of MND, and combined GSTP1 polymorphisms in codon 105 and 114 may result in lower protection of MND patients against the toxicity of electrophilic compounds, organic and inorganic hydroperoxides.

Biochemical effects of vinyl chloride monomer on the liver of occupationally exposed workers.

PubMed

Saad, A A; el-Sewedy, S M; Bader, G A; Mousa, S M; Mahdy, M M

2000-01-01

We investigated the effects of vinyl chloride monomer exposure on the liver of 86 workers by measuring beta-glucuronidase, arylsulfatase A, adenosine deaminase, 5'-nucleotidase and routine liver function enzymes in the sera of the workers. In 21 of them, three or more of these parameters were raised, with a significant decrease in the level of blood glutathione and a significant increase in the enzyme activity level of glutathione S-transferase. Of these 21 workers, 14 had fatty liver infiltration, 8 of whom were also suffering from liver enlargement. Also, 4 workers had liver enlargement without fatty infiltration and 3 had enlarged spleens. The study highlights the need for vigilance in environmental monitoring and medical surveillance of workers exposed to this chemical.

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

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.

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.

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.

Reactions of benzene oxide with thiols including glutathione.

PubMed

Henderson, Alistair P; Barnes, Martine L; Bleasdale, Christine; Cameron, Richard; Clegg, William; Heath, Sarah L; Lindstrom, Andrew B; Rappaport, Stephen M; Waidyanatha, Suramya; Watson, William P; Golding, Bernard T

2005-02-01

S-Phenylmercapturic acid is a minor metabolite of benzene used as a biomarker for human benzene exposures. The reaction of intracellular glutathione with benzene oxide-oxepin, the initial metabolite of benzene, is presumed to give 1-(S-glutathionyl)-cyclohexa-3,5-dien-2-ol, which undergoes dehydration to S-phenylglutathione, the precursor of S-phenylmercapturic acid. To validate the proposed route to S-phenylglutathione, reactions of benzene oxide-oxepin with glutathione and other sulfur nucleophiles have been studied. The reaction of benzene oxide with an excess of aqueous sodium sulfide, followed by acetylation, gave bis-(6-trans-5-acetoxycyclohexa-1,3-dienyl)sulfide, the structure of which was proved by X-ray crystallography. Reactions of benzene oxide-oxepin in a 95:5 (v/v) mixture of phosphate buffer in D2O with (CD3)2SO were monitored by 1H NMR spectroscopy. In the absence of glutathione, the half-life of benzene oxide-oxepin was ca. 34 min at 25 degrees C and pD 7.0. The half-life was not affected in the range of 2-15 mM glutathione in the presence and absence of a commercial sample of human glutathione S-transferase (at pH 7.0, 8.0, 8.5, or 10.0). The adduct 1-(S-glutathionyl)-cyclohexa-3,5-diene-2-ol was identified in these reaction mixtures, especially at higher pH, by mass spectrometry and by its acid-catalyzed decomposition to S-phenylglutathione. Incubation of benzene oxide with N-acetyl-L-cysteine at 37 degrees C and pH 10.0 and subsequent mass spectrometric analysis of the mixture showed formation of pre-S-phenylmercapturic acid and the dehydration product, S-phenylmercapturic acid. The data validate the premise that benzene oxide-oxepin can be captured by glutathione to give (1R,2R)- and/or (1S,2S)-1-(S-glutathionyl)-cyclohexa-3,5-dien-2-ol, which dehydrate to S-phenylglutathione. The capture is a relatively inefficient process at pH 7 that is accelerated at higher pH. These studies account for the observation that the metabolism of benzene is dominated by the formation of phenol. The pathway leading to S-phenylmercapturic acid is necessarily minor on account of the low efficiency of benzene oxide capture by glutathione at pH 7 vs spontaneous rearrangement to phenol.

Hypermethylation of the Human Glutathione S-Transferase-π Gene (GSTP1) CpG Island Is Present in a Subset of Proliferative Inflammatory Atrophy Lesions but Not in Normal or Hyperplastic Epithelium of the Prostate

PubMed Central

Nakayama, Masashi; Bennett, Christina J.; Hicks, Jessica L.; Epstein, Jonathan I.; Platz, Elizabeth A.; Nelson, William G.; De Marzo, Angelo M.

2003-01-01

Somatic inactivation of the glutathione S-transferase-π gene (GSTP1) via CpG island hypermethylation occurs early during prostate carcinogenesis, present in ∼70% of high-grade prostatic intraepithelial neoplasia (high-grade PIN) lesions and more than 90% of adenocarcinomas. Recently, there has been a resurgence of the concept that foci of prostatic atrophy (referred to as proliferative inflammatory atrophy or PIA) may be precursor lesions for the development of prostate cancer and/or high-grade PIN. Many of the cells within PIA lesions contain elevated levels of GSTP1, glutathione S-transferase-α (GSTA1), and cyclooxygenase-II proteins, suggesting a stress response. Because not all PIA cells are positive for GSTP1 protein, we hypothesized that some of the cells within these regions acquire GSTP1 CpG island hypermethylation, increasing the chance of progression to high-grade PIN and/or adenocarcinoma. Separate regions (n =199) from 27 formalin-fixed paraffin-embedded prostates were microdissected by laser-capture microdissection (Arcturus PixCell II). These regions included normal epithelium (n = 48), hyperplasticepithelium from benign prostatic hyperplasia nodules (n = 22), PIA (n = 64), high-grade PIN (n = 32), and adenocarcinoma (n = 33). Genomic DNA was isolated and assessed for GSTP1 CpG island hypermethylation by methylation-specific polymerase chain reaction. GSTP1 CpG island hypermethylation was not detected in normal epithelium (0 of 48) or in hyperplastic epithelium (0 of 22), but was found in 4 of 64 (6.3%) PIA lesions. The difference in the frequency of GSTP1 CpG island hypermethylation between normal or hyperplastic epithelium and PIA was statistically significant (P = 0.049). Similar to studies using nonmicrodissected cases, hypermethylation was found in 22 of 32 (68.8%) high-grade PIN lesions and in 30 of 33 (90.9%) adenocarcinoma lesions. Unlike normal or hyperplastic epithelium, GSTP1 CpG island hypermethylation can be detected in some PIA lesions. These data support the hypothesis that atrophic epithelium in a subset of PIA lesions may lead to high-grade PIN and/or adenocarcinoma. Because these atrophic lesions are so prevalent and extensive, even though only a small subset contains this somatic DNA alteration, the clinical impact may be substantial. PMID:12937133

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 competitively with respect to CDNB. While red pomegranate extracts inhibited rRaGST activity competitively with respect to GSH, uncompetitive inhibition was observed with respect to CDNB. Copyright © 2014 Elsevier GmbH. All rights reserved.

Oxidative Damage Induced by Arsenic in Mice or Rats: A Systematic Review and Meta-Analysis.

PubMed

Xu, Mengchuan; Rui, Dongsheng; Yan, Yizhong; Xu, Shangzhi; Niu, Qiang; Feng, Gangling; Wang, Yan; Li, Shugang; Jing, Mingxia

2017-03-01

In this meta-analysis, studies reporting arsenic-induced oxidative damage in mouse models were systematically evaluated to provide a scientific understanding of oxidative stress mechanisms associated with arsenic poisoning. Fifty-eight relevant peer-reviewed publications were identified through exhaustive database searching. Oxidative stress indexes assessed included superoxide dismutase (SOD), catalase (CAT), glutathione (GSH), glutathione peroxidase (GPx), glutathione-s-transferase (GST), glutathione reductase (GR), oxidized glutathione (GSSG), malondialdehyde (MDA), and reactive oxygen species (ROS). Our meta-analysis showed that arsenic exposure generally suppressed measured levels of the antioxidants, SOD, CAT, GSH, GPx, GST, and GR, but increased levels of the oxidants, GSSG, MDA, and ROS. Arsenic valence was important and GR and MDA levels increased to a significantly (P < 0.05) greater extent upon exposure to As 3+ than to As 5+ . Other factors that contributed to a greater overall oxidative effect from arsenic exposure included intervention time, intervention method, dosage, age of animals, and the sample source from which the indexes were estimated. Our meta-analysis effectively summarized a wide range of studies and detected a positive relationship between arsenic exposure and oxidative damage. These data provide a scientific basis for the prevention and treatment of arsenic poisoning.

Cytotoxicity of the dicarboximide fungicides, vinclozolin and iprodione, in rat hepatoma-derived Fa32 cells.

PubMed

Dierickx, Paul J

2004-10-01

Dicarboximide fungicides are widely used to control various fungal species. Their primary action is not known, due to a lack of knowledge concerning the mechanism of action of the dicarboximide group. The cytotoxicities of vinclozolin and iprodione in rat hepatoma-derived Fa32 cells were investigated. Cytotoxicity was measured by neutral red uptake inhibition after treatment for 24 hours. Iprodione was more toxic than vinclozolin. Vinclozolin was less toxic in glutathione-depleted cells than in control cells. This was also true for iprodione at lower concentrations, but iprodione became more toxic at higher concentrations. Both the fungicides increased the endogenous glutathione content by 20% after 1 hour. After 24 hours, the glutathione content was doubled by vinclozolin, but was not affected by iprodione. No effect on glutathione S-transferase activity or reactive oxygen species formation could be observed. Cytochrome P450-dependent ethoxyresorufin-O-deethylase and pentoxyresorufin-O-depentylase activities were moderately activated by iprodione and strongly activated by vinclozolin. A glutathione-related cytochrome P450-dependent metabolic attack of vinclozolin and iprodione could be responsible for their cytotoxicity in Fa32 cells. Further research is needed to fully elucidate these (or other) mechanisms.

Protective effect of Corchorus olitorius leaves on sodium arsenite-induced toxicity in experimental rats.

PubMed

Das, Anup K; Bag, Sujit; Sahu, Ranabir; Dua, Tarun K; Sinha, Mohit K; Gangopadhyay, Moumita; Zaman, Kamaruz; Dewanjee, Saikat

2010-01-01

The present study was undertaken to evaluate the protective effect of aqueous extract of Corchorus olitorius leaves (AECO) against sodium arsenite-induced toxicity in experimental rats. The animals exposed to sodium arsenite at a dose of 10mg/kg body weight p.o. for 10days exhibited a significant inhibition (p<0.01) of hepatic and renal antioxidant enzymes namely superoxide dismutase, catalase, glutathione-S-transferase, glutathione peroxidase and glutathione reductase. In addition, arsenic intoxication significantly decreased (p<0.01) the level of reduced glutathione and increased (p<0.01) the levels of oxidized glutathione and thiobarbituric acid reactive substances in selected tissues. Treatment with AECO at doses of 50 and 100mg/kg body weight p.o. for 15days prior to arsenic intoxication significantly improved hepatic and renal antioxidant markers in a dose dependant manner. AECO treatment also significantly reduced the arsenic-induced DNA fragmentation of hepatic and renal tissues. Histological studies on the ultrastructural changes of liver and kidney supported the protective activity of the AECO. The results concluded that the treatment with AECO prior to arsenic intoxication has significant role in protecting animals from arsenic-induced hepatic and renal toxicity. Copyright 2009 Elsevier Ltd. All rights reserved.

Oxidative stress protection and glutathione metabolism in response to hydrogen peroxide and menadione in riboflavinogenic fungus Ashbya gossypii.

PubMed

Kavitha, S; Chandra, T S

2014-11-01

Ashbya gossypii is a plant pathogen and a natural overproducer of riboflavin and is used for industrial riboflavin production. A few literature reports depict a link between riboflavin overproduction and stress in this fungus. However, the stress protection mechanisms and glutathione metabolism are not much explored in A. gossypii. In the present study, an increase in the activity of catalase and superoxide dismutase was observed in response to hydrogen peroxide and menadione. The lipid peroxide and membrane lipid peroxide levels were increased by H2O2 and menadione, indicating oxidative damage. The glutathione metabolism was altered with a significant increase in oxidized glutathione (GSSG), glutathione peroxidase (GPX), glutathione S transferase (GST), and glutathione reductase (GR) and a decrease in reduced glutathione (GSH) levels in the presence of H2O2 and menadione. Expression of the genes involved in stress mechanism was analyzed in response to the stressors by semiquantitative RT-PCR. The messenger RNA (mRNA) levels of CTT1, SOD1, GSH1, YAP1, and RIB3 were increased by H2O2 and menadione, indicating the effect of stress at the transcriptional level. A preliminary bioinformatics study for the presence of stress response elements (STRE)/Yap response elements (YRE) depicted that the glutathione metabolic genes, stress genes, and the RIB genes hosted either STRE/YRE, which may enable induction of these genes during stress.

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

Glutathione depletion activates the yeast vacuolar transient receptor potential channel, Yvc1p, by reversible glutathionylation of specific cysteines

PubMed Central

Chandel, Avinash; Das, Krishna K.; Bachhawat, Anand K.

2016-01-01

Glutathione depletion and calcium influx into the cytoplasm are two hallmarks of apoptosis. We have been investigating how glutathione depletion leads to apoptosis in yeast. We show here that glutathione depletion in yeast leads to the activation of two cytoplasmically inward-facing channels: the plasma membrane, Cch1p, and the vacuolar calcium channel, Yvc1p. Deletion of these channels partially rescues cells from glutathione depletion–induced cell death. Subsequent investigations on the Yvc1p channel, a homologue of the mammalian TRP channels, revealed that the channel is activated by glutathionylation. Yvc1p has nine cysteine residues, of which eight are located in the cytoplasmic regions and one on the transmembrane domain. We show that three of these cysteines, Cys-17, Cys-79, and Cys-191, are specifically glutathionylated. Mutation of these cysteines to alanine leads to a loss in glutathionylation and a concomitant loss in calcium channel activity. We further investigated the mechanism of glutathionylation and demonstrate a role for the yeast glutathione S-transferase Gtt1p in glutathionylation. Yvc1p is also deglutathionylated, and this was found to be mediated by the yeast thioredoxin, Trx2p. A model for redox activation and deactivation of the yeast Yvc1p channel is presented. PMID:27708136

Glutathione system participation in thoracic aneurysms from patients with Marfan syndrome.

PubMed

Zúñiga-Muñoz, Alejandra María; Pérez-Torres, Israel; Guarner-Lans, Verónica; Núñez-Garrido, Elías; Velázquez Espejel, Rodrigo; Huesca-Gómez, Claudia; Gamboa-Ávila, Ricardo; Soto, María Elena

2017-05-01

Aortic dilatation in Marfan syndrome (MFS) is progressive. It is associated with oxidative stress and endothelial dysfunction that contribute to the early acute dissection of the vessel and can result in rupture of the aorta and sudden death. We evaluated the participation of the glutathione (GSH) system, which could be involved in the mechanisms that promote the formation and progression of the aortic aneurysms in MFS patients. Aortic aneurysm tissue was obtained during chest surgery from eight control subjects and 14 MFS patients. Spectrophotometrical determination of activity of glutathione peroxidase (GPx), glutathione-S-transferase (GST), glutathione reductase (GR), lipid peroxidation (LPO) index, carbonylation, total antioxidant capacity (TAC), and concentration of reduced and oxidized glutathione (GSH and GSSG respectively), was performed in the homogenate from aortic aneurysm tissue. LPO index, carbonylation, TGF-β1, and GR activity were increased in MFS patients (p < 0.04), while TAC, GSH/GSSG ratio, GPx, and GST activity were significantly decreased (p < 0.04). The depletion of GSH, in spite of the elevated activity of GR, not only diminished the activity of GSH-depend GST and GPx, but increased LPO, carbonylation and decreased TAC. These changes could promote the structural and functional alterations in the thoracic aorta of MFS patients.

Vernonia cinerea L. scavenges free radicals and regulates nitric oxide and proinflammatory cytokines profile in carrageenan induced paw edema model.

PubMed

Kumar, P Pratheesh; Kuttan, Girija

2009-01-01

In this study, we evaluated the anti-oxidant and anti-inflammatory activities of the medicinal plant, Vernonia cinerea L (Asteraceae) using in vitro as well as in vivo models. Methanolic extract of Vernonia cinerea was found to scavenge the hydroxyl radical generated by Fenton reaction (IC(50)130 microg/ml), Superoxide generated by photo reduction of riboflavin (IC(50)190 microg/ml) and inhibited lipid peroxidation significantly (IC(50)130.5 microg/ml). The drug also scavenged nitric oxide (IC(50)210 microg/ml). Intraperitoneal administration of Vernonia cinerea was found to inhibit the PMA induced Superoxide generation in mice peritoneal macrophages. The administration of Vernonia cinerea to mice significantly increased the levels of catalase, superoxide dismutase, glutathione, glutathione peroxidase and glutathione-S transferase in blood and liver, whereas lipid peroxidation activity was significantly decreased. It was also found that Vernonia cinerea extract significantly inhibited carrageenan induced inflammation, compared with control models. Down regulation of pro-inflammatory cytokine level and gene expression were also support the above result.

Hepatoprotective effects of fermented Curcuma longa L. on carbon tetrachloride-induced oxidative stress in rats.

PubMed

Kim, Yongjae; You, Yanghee; Yoon, Ho-Geun; Lee, Yoo-Hyun; Kim, Kyungmi; Lee, Jeongmin; Kim, Min Soo; Kim, Jong-Choon; Jun, Woojin

2014-05-15

The hepatoprotective effect of fermented Curcuma longa L. (FC) was investigated in rats under CCl4-induced oxidative stress. FC at a dose of 30 or 300 mg/kg body weight (b.w.) was orally administered for 14 days followed by a single dose of CCl4 (1.25 mL/kg b.w. in 20% corn oil) on day 14. Pretreatment with FC drastically prevented the elevated activities of serum AST, ALT, LDH, and ALP caused by CCl4-induced hepatotoxicity. Histopathologically evident hepatic necrosis was significantly ameliorated by FC pretreatment. When compared to the CCl4-alone treated group, rats pretreated with FC displayed the reduced level of malondialdehyde. Furthermore, FC enhanced antioxidant capacities with higher activities of catalase, glutathione-S-transferase, glutathione reductase, and glutathione peroxidase, and level of reduced glutathione. These results suggest that FC could be a candidate used for the prevention against various liver diseases induced by oxidative stress via elevating antioxidative potentials and decreasing lipid peroxidation. Copyright © 2013 Elsevier Ltd. All rights reserved.

Effect of thiacloprid on early life stages of common carp (Cyprinus carpio).

PubMed

Velisek, Josef; Stara, Alzbeta

2018-03-01

Toxicity of the neonicotinoid pesticide thiacloprid to embryos and larvae of common carp Cyprinus carpio was assessed under laboratory conditions. Carp embryos and larvae were exposed to thiacloprid at four concentrations: 4.5 (environmental concentration), 45, 225, and 450 μg/L for 35 days and compared to a non-treated control group. The effects on lipid peroxidation, antioxidant enzyme levels (superoxide dismutase, glutathione reductase, catalase, glutathione S-transferase, and reduced glutathione), mortality, growth, development, and histopathogenesis were assessed. Thiacloprid at tested concentrations were not associated with negative effects on hatching, behaviour, embryo viability, or Fulton's condition factor. Carp exposed to 45 μg/L thiacloprid showed lower weight and length compared to controls. Thiacloprid at 225 and 450 μg/L delayed development and led to lower weight and length of carp. Significantly lower superoxide dismutase and glutathione reductase activity was observed at all tested concentrations of thiacloprid compared with the control group. Chronic thiacloprid exposure of early-life stages of carp affected ontogeny and growth rate, and inhibited antioxidant capacity. Copyright © 2017 Elsevier Ltd. All rights reserved.

Accelerated Tumor Cell Death by Anglogenic Modifiers

DTIC Science & Technology

2005-08-01

Loudy DE , Wallace CD, 32A: 2413-2422, 1996 Montgomery LR, Nestok BR: Microautoradiographic quan- 24 . Claffet K.P, Robinson GS: Regulation of VEGF/VPF...colonic epithelial cells, and B cells. IL-6 produc- ing prostate cancer ( De Marzo et al., 1999). The hypo- tion is generally correlated with cell...glutathione S-transferase of malignancy (Giri et al., 2001), again suggesting a "vi- (GSTP1) ( De Marzo et al., 1999). In vivo study of H202 cious

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

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.

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.

GSTM1 null polymorphism at the glutathione S-transferase M1 locus: phenotype and genotype studies in patients with primary biliary cirrhosis.

PubMed Central

Davies, M H; Elias, E; Acharya, S; Cotton, W; Faulder, G C; Fryer, A A; Strange, R C

1993-01-01

Studies were carried out to test the hypothesis that the GSTM1 null phenotype at the mu (mu) class glutathione S-transferase 1 locus is associated with an increased predisposition to primary biliary cirrhosis. Starch gel electrophoresis was used to compare the prevalence of GSTM1 null phenotype 0 in patients with end stage primary biliary cirrhosis and a group of controls without evidence of liver disease. The prevalence of GSTM1 null phenotype in the primary biliary cirrhosis and control groups was similar; 39% and 45% respectively. In the primary biliary cirrhosis group all subjects were of the common GSTM1 0, GSTM1 A, GSTM1 B or GSTM1 A, B phenotypes while in the controls, one subject showed an isoform with an anodal mobility compatible with it being a product of the putative GSTM1*3 allele. As the GSTM1 phenotype might be changed by the disease process, the polymerase chain reaction was used to amplify the exon 4-exon 5 region of GSTM1 and show that in 13 control subjects and 11 patients with primary biliary cirrhosis, GSTM1 positive and negative genotypes were associated with corresponding GSTM1 expressing and non-expressing phenotypes respectively. The control subject with GSTM1 3 phenotype showed a positive genotype. Images Figure 1 Figure 2 PMID:8491405

Glutathione S-transferase M1 (GSTM1) null genotype and coronary artery disease risk: a meta-analysis.

PubMed

Zhang, Zhen-Xian; Zhang, Ye

2014-01-01

The Glutathione S-Transferase M1 (GSTM1) null genotype has been indicated to be correlated with coronary artery disease (CAD) susceptibility, but study results are still debatable. Thus, a meta-analysis was conducted. Databases including PubMed, Embase, Web of Science, and Chinese National Knowledge Infrastructure (CNKI) were searched. Data were extracted and pooled odds ratios (OR) with 95% confidence intervals (CI) were calculated. Twenty-six studies with 10595 cases and 13782 controls were included in this meta-analysis. The association between GSTM1 null genotype and CAD risk was significant (OR = 1.35; 95% CI, 1.09 - 1.67; P < 0.01). When stratified by ethnicity, the significantly elevated risk were observed in Caucasians (OR = 1.39; 95% CI, 1.07 - 1.81; P = 0.01) but not in Asians (OR = 1.27; 95% CI, 0.87 - 1.86; P = 0.22). No significantly increased myocardial infarction risk was observed (OR = 0.96; 95% CI, 0.78 - 1.18; P = 0.68). Subgroup analysis on the smoking status showed that the increased risk was found in smokers (OR = 1.66; 95% CI, 1.14 - 2.42; P < 0.01) but not in non-smokers (OR = 1.30; 95% CI, 1.74 - 2.28; P = 0.37). In conclusion, this meta-analysis suggested that GSTM1 null genotype was a risk factor for CAD, especially in Caucasians and smokers.

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

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.

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.

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.

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.

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

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 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

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-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-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.

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.

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.

Dietary Isothiocyanates, Glutathione S-Transferase M1 (GSTM1), and Lung Cancer Risk in African Americans and Caucasians from Los Angeles County, California

PubMed Central

Carpenter, Catherine L.; Yu, Mimi C.; London, Stephanie J.

2013-01-01

Isothiocyanates, found in cruciferous vegetables, are anti-carcinogenic. Racial differences in smoking do not fully account for the African American excess lung cancer incidence. African Americans consume more cruciferous vegetables than US Whites. Impact on lung cancer risk is unknown. Glutathione S transferase M1 (GSTM1) gene promotes urinary isothiocyanate excretion. We evaluated dietary isothiocyanates and lung cancer using a population-based case-control study of 933 African Americans and Caucasians (non-Hispanic US White) from Los Angeles County, California (311 cases; 622 controls). Broccoli, cauliflower, greens and cabbage food-frequency variables represented isothiocyanates. Isothiocyanates were protective for lung cancer risk. Adjusted odds ratio (OR) for the uppermost quartile, > 80 μMol isothiocyanates/week, compared to lowest, was 0.65 (95% confidence interval (CL) = 0.41 – 1.00, trend p = 0.02). Association was stronger among subjects with homozygous deletion of GSTM1 (OR=0.52; 95% CL = 0.31 – 0.86), than subjects with at least one GSTM1 copy (OR = 0.77; 95% CL = 0.49 – 1.21). Difference was not statistically significant (p = 0.16). Despite African Americans consuming more cruciferous vegetables, the isothiocyanate association did not vary by race (p=0.52). Reduced lung cancer risk with higher isothiocyanate intake may be slightly stronger among subjects with deletion of GSTM1. PMID:19838921

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.

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

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

Aphids transform and detoxify the mycotoxin deoxynivalenol via a type II biotransformation mechanism yet unknown in animals.

PubMed

De Zutter, N; Audenaert, K; Arroyo-Manzanares, N; De Boevre, M; Van Poucke, C; De Saeger, S; Haesaert, G; Smagghe, G

2016-12-08

Biotransformation of mycotoxins in animals comprises phase I and phase II metabolisation reactions. For the trichothecene deoxynivalenol (DON), several phase II biotransformation reactions have been described resulting in DON-glutathiones, DON-glucuronides and DON-sulfates made by glutathione-S-transferases, uridine-diphosphoglucuronyl transferases and sulfotransferases, respectively. These metabolites can be easily excreted and are less toxic than their free compounds. Here, we demonstrate for the first time in the animal kingdom the conversion of DON to DON-3-glucoside (DON-3G) via a model system with plant pathogenic aphids. This phase II biotransformation mechanism has only been reported in plants. As the DON-3G metabolite was less toxic for aphids than DON, this conversion is considered a detoxification reaction. Remarkably, English grain aphids (Sitobion avenae) which co-occur with the DON producer Fusarium graminearum on wheat during the development of fusarium symptoms, tolerate DON much better and convert DON to DON-3G more efficiently than pea aphids (Acyrthosiphon pisum), the latter being known to feed on legumes which are no host for F. graminearum. Using a non-targeted high resolution mass spectrometric approach, we detected DON-diglucosides in aphids probably as a result of sequential glucosylation reactions. Data are discussed in the light of an eventual co-evolutionary adaptation of S. avenae to DON.

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.

Glutathione S-transferase M1 genotypes and the risk of vulvar cancer: a population-based case-control study.

PubMed

Chen, C; Madeleine, M M; Weiss, N S; Daling, J R

1999-09-01

Glutathione S-transferases (GSTs) facilitate the excretion of a variety of potential carcinogens. Some 50-60% of Caucasians are homozygous for the null allele of GSTM1, a gene responsible for the presence of one of these enzymes. The authors examined whether women with the GSTM1 null genotype are at altered risk of vulvar cancer. They obtained peripheral blood specimens from 18- to 79-year-old residents of King, Pierce, and Snohomish counties of western Washington who were diagnosed with vulvar cancer between April 1991 and June 1994. Blood specimens were also obtained from controls identified via random digit telephone dialing of western Washington households. The authors determined the GSTM1 genotype of 137 cases (120 in situ and 17 invasive cases) and 248 controls. The frequency of the GSTM1 null genotype was 46.7% among cases and 57.3% among controls. The age-adjusted odds ratio associated with the GSTM1 null genotype was 0.7 (95% confidence interval: 0.4, 1.0). Among current smokers of cigarettes, the age-adjusted odds ratio associated with the GSTM1 null genotype was 0.5 (95% confidence interval: 0.2, 0.9), differing little between heavy and light smokers. Our data suggest that women with the GSTM1 null genotype are not at increased risk of vulvar cancer.

Aphids transform and detoxify the mycotoxin deoxynivalenol via a type II biotransformation mechanism yet unknown in animals

PubMed Central

De Zutter, N.; Audenaert, K.; Arroyo-Manzanares, N.; De Boevre, M.; Van Poucke, C.; De Saeger, S.; Haesaert, G.; Smagghe, G.

2016-01-01

Biotransformation of mycotoxins in animals comprises phase I and phase II metabolisation reactions. For the trichothecene deoxynivalenol (DON), several phase II biotransformation reactions have been described resulting in DON-glutathiones, DON-glucuronides and DON-sulfates made by glutathione-S-transferases, uridine-diphosphoglucuronyl transferases and sulfotransferases, respectively. These metabolites can be easily excreted and are less toxic than their free compounds. Here, we demonstrate for the first time in the animal kingdom the conversion of DON to DON-3-glucoside (DON-3G) via a model system with plant pathogenic aphids. This phase II biotransformation mechanism has only been reported in plants. As the DON-3G metabolite was less toxic for aphids than DON, this conversion is considered a detoxification reaction. Remarkably, English grain aphids (Sitobion avenae) which co-occur with the DON producer Fusarium graminearum on wheat during the development of fusarium symptoms, tolerate DON much better and convert DON to DON-3G more efficiently than pea aphids (Acyrthosiphon pisum), the latter being known to feed on legumes which are no host for F. graminearum. Using a non-targeted high resolution mass spectrometric approach, we detected DON-diglucosides in aphids probably as a result of sequential glucosylation reactions. Data are discussed in the light of an eventual co-evolutionary adaptation of S. avenae to DON. PMID:27929076

Organometallic ruthenium anticancer complexes inhibit human glutathione-S-transferase π.

PubMed

Lin, Yu; Huang, Yongdong; Zheng, Wei; Wang, Fuyi; Habtemariam, Abraha; Luo, Qun; Li, Xianchan; Wu, Kui; Sadler, Peter J; Xiong, Shaoxiang

2013-11-01

The organometallic ruthenium(II) anticancer complexes [(η(6)-arene)Ru(en)Cl](+) (arene = p-cymene (1), biphenyl (2) or 9,10-dihydrophenanthrene (3); en = ethylenediamine), exhibit in vitro and in vivo anticancer activities. In the present work, we show that they inhibit human glutathione-S-transferase π (GSTπ) with IC50 values of 59.4 ± 1.3, 63.2 ± 0.4 and 37.2 ± 1.1 μM, respectively. Mass spectrometry revealed that complex 1 binds to the S-donors of Cys15, Cys48 within the G-site and Cys102 at the interface of the GSTπ dimer, while complex 2 binds to Cys48 and Met92 at the dimer interface and complex 3 to Cys15, Cys48 and Met92. Moreover, the binding of complex 1 to Cys15 and Cys102, complex 2 to Cys48 and complex 3 to Cys15 induces the irreversible oxidation of the coordinated thiolates to sulfenates. Molecular modeling studies indicate that the coordination of the {(arene)Ru(en)}(2+) fragment to Cys48 blocks the hydrophilic G-site sterically, perhaps preventing substrate from proper positioning and accounting for the reduction in enzymatic activity of ruthenated GSTπ. The binding of the ruthenium arene complexes to Cys102 or Met92 disrupts the dimer interface which is an essential structural feature for the proper functioning of GSTπ, perhaps also contributing to the inhibition of GSTπ. © 2013.

A multi-biomarker approach in scallop Chlamys farreri to assess the impact of contaminants in Qingdao coastal area of China.

PubMed

Guo, Ruiming; Pan, Luqing; Ji, Rongwang

2017-08-01

A multi-biomarker approach was carried out to classify the environmental quality and the adverse effects of contaminants on scallop Chlamys farreri. The scallops were collected from three sampling stations in Qingdao coastal area of China in March, May, August and October of 2015. A suite of environmental factors and biomarkers, including temperature, salinity, pH, the concentrations of polycyclic aromatic hydrocarbons (PAHs), tetrabromobisphenol A (TBBPA) and metals (Cr, Mn, Cu, Zn, Cd, Pb, As) in seawater and soft tissue, mRNA expression of aryl hydrocarbon receptor (AhR) and P-glycoprotein (P-gp), 7-ethoxyresorufin O-deethylase (EROD), glutathione-S-transferase (GST), uridine-diphosphate-glucuronyl-transferase (UGT), sulfotransferase (SULT), metallothionein (MT), Superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT), lipid peroxidation (LPO) and protein carbonyl (PC) contents and DNA strand breaks, were measured in the gill and digestive gland. The results showed that S2 was the most polluted while S1 was identified the least polluted. Despite the differentiation of pollution levels and environmental parameters the selected biomarkers responded efficiently to contaminants. Principal component analysis (PCA) revealed that EROD for PAHs, AhR for TBBPA, MT for Cr, Pb and Mn, LPO and PC for Zn were the effective biomarkers respectively. This study demonstrated that the application of multi-biomarker approach in conjunction with the traditional analysis of environmental parameters and contaminants provided valuable information in environmental risk assessment. Copyright © 2017 Elsevier Inc. All rights reserved.

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.

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

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.

Effects of Kombucha on oxidative stress induced nephrotoxicity in rats

PubMed Central

2009-01-01

Background Trichloroethylene (TCE) may induce oxidative stress which generates free radicals and alters antioxidants or oxygen-free radical scavenging enzymes. Methods Twenty male albino rats were divided into four groups: (1) the control group treated with vehicle, (2) Kombucha (KT)-treated group, (3) TCE-treated group and (4) KT/TCE-treated group. Kidney lipid peroxidation, glutathione content, nitric oxide (NO) and total blood free radical concentrations were evaluated. Serum urea, creatinine level, gamma-glutamyl transferase (GGT) and lactate dehydrogenase (LDH) activities were also measured. Results TCE administration increased the malondiahyde (MDA) and NO contents in kidney, urea and creatinine concentrations in serum, total free radical level in blood and GGT and LDH activities in serum, whereas it decreased the glutathione (GSH) level in kidney homogenate. KT administration significantly improved lipid peroxidation and oxidative stress induced by TCE. Conclusion The present study indicates that Kombucha may repair damage caused by environmental pollutants such as TCE and may be beneficial to patient suffering from renal impairment. PMID:19943946

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

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. PMID:20712880

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 the conjugation of anthocyanin pigments and in their transport into the vacuole, specifically in fruit flesh of the pigmented cultivar. PMID:24490620

Prevention of carbon tetrachloride (CCl4)-induced toxicity in testes of rats treated with Physalis peruviana L. fruit.

PubMed

Abdel Moneim, Ahmed E

2016-06-01

Treatment of rats with carbon tetrachloride (CCl4; 2 ml/kg body weight) once a week for 12 weeks caused a significant decrease in serum levels of testosterone, luteinizing hormone, and follicle-stimulating hormone. These decreases in sex hormones were reduced with Physalis peruviana L. (Cape gooseberry) juice supplementation. In addition, testicular activity of antioxidant enzymes such as superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, and glutathione-S-transferase suppressed with CCl4 were elevated after P. peruviana juice supplements. P. peruviana juice supplementation significantly increased the testicular glutathione and significantly decreased the level of lipid peroxidation and the nitric oxide production compared with the CCl4 group. In addition, the decline in the activity of antioxidant enzymes after CCl4 was ameliorated by P. peruviana Moreover, degeneration of germ and Leydig cells along with deformities in spermatogenesis induced after CCl4 injections were prevented with the supplementation of P. peruviana juice. Furthermore, P. peruviana juice attenuated CCl4-induced apoptosis in testes tissue by inhibition of caspase-3 activity. The results clearly demonstrate that P. peruviana juice augments the antioxidants defense mechanism against CCl4-induced reproductive toxicity and provides evidence that the juice may have a therapeutic role in free radical-mediated diseases and infertility. © The Author(s) 2014.

Hepatoprotective and Antioxidant Effect of Mangifera Indica Leaf Extracts against Mercuric Chloride-induced Liver Toxicity in Mice.

PubMed

Karuppanan, Muthupillai; Krishnan, Manigandan; Padarthi, Pavankumar; Namasivayam, Elangovan

2014-01-01

To explore the antioxidant and hepatoprotective effect of ethanolic Mangifera indica (EMI) and methanolic Mangifera indica (MMI) leaf extracts in mercuric chloride (HgCl 2 ) induced toxicity in Swiss albino mice. Toxicity in mice was induced with HgCl 2 (5.0 mg/kg, i.p.), followed by oral intervention with EMI and MMI extracts (25 mg and 50 mg/kg. body wt.) for 30 days. The extent of liver damage was assessed from the extents of histopathological, morphological, antioxidant and liver enzymes. Mercuric chloride-induced mice showed an increased cellular damage whereas leaf extracts of EMI and MMI-treated mice showed recovery of damaged hepatocytes. Mercuric chloride intoxicated mice exhibited a significant (p < 0.05) elevation in the liver enzymes (Aspartate amino transferase and Alanine amino transferase) and gradual decline in the cellular radical scavenging enzyme levels (Catalase, Glutathione-s-transferase and Glutathione peroxidase. The combined treatment with EMI and MMI leaf extracts significantly (p < 0.05) reversed these parameters. However, the effects of MMI leaf extract (50 mg/kg) were superior to those of EMI- treated mice possibly due to its potent radical scavenging property. These results suggest that oral supplementation of Mangifera indica extract remarkably reduces hepatotoxicity in mice possibly through its antioxidant potentials. How to cite this article: Karuppanan M, Krishnan M, Padarthi P, Namasivayam E. Hepatoprotec-tive and Antioxidant Effect of Mangifera Indica Leaf Extracts against Mercuric Chloride-induced Liver Toxicity in Mice. Euroasian J Hepato-Gastroenterol 2014;4(1):18-24.

Alterations in Grapevine Leaf Metabolism Occur Prior to Esca Apoplexy Appearance.

PubMed

Magnin-Robert, Maryline; Adrian, Marielle; Trouvelot, Sophie; Spagnolo, Alessandro; Jacquens, Lucile; Letousey, Patricia; Rabenoelina, Fanja; Harir, Mourad; Roullier-Gall, Chloé; Clément, Christophe; Schmitt-Kopplin, Philippe; Vallat, Armelle; Abou-Mansour, Eliane; Fontaine, Florence

2017-12-01

Esca disease is one of the major grapevine trunk diseases in Europe and the etiology is complex, since several inhabiting fungi are identified to be associated with this disease. Among the foliar symptom expressions, the apoplectic form may be distinguished and characterized by sudden dieback of shoots, leaf drop, and shriveling of grape clusters in a few days that can ultimately induce the plant death. To further understand this drastic event, we conducted transcriptomic and metabolomic analyses to characterize responses of leaves during the period preceding symptom appearance (20 and 7 days before foliar symptom expression) and at the day of apoplexy expression. Transcriptomic and metabolomic analyses provide signatures for the apoplectic leaves and most changes concerning the metabolism of carbohydrates, amino acids, and phenylpropanoids. In deciphering glutathione-S-transferase (GST), its preferential location in phloem, correlated with the upregulation of GST genes and a decrease of the glutathione level, offers further support to the putative role of glutathione during apoplexy expression.

Effects of dietary menadione on the activity of antioxidant enzymes in abalone, Haliotis discus hannai Ino

NASA Astrophysics Data System (ADS)

Fu, Jinghua; Xu, Wei; Mai, Kangsen; Zhang, Wenbing; Feng, Xiuni; Liufu, Zhiguo

2012-01-01

A 240-day growth experiment in a re-circulating water system was conducted to investigate the effects of dietary menadione on the growth and antioxidant responses of abalone Haliotis discus hannai Ino. Triplicate groups of juvenile abalone (initial weight: 1.19 ± 0.01 g; shell length: 19.23 ± 0.01 mm) were fed to satiation with 3 semi-purified diets containing 0, 10, and 1 000 mg menadione sodium bisulfite (MSB)/kg, respectively. Results show that there were no significant differences in the rate of weight gain or in the daily increment in shell length of abalone among different treatments. Activities of superoxide dismutase (SOD), glutathione peroxidase (GPX), glutathione S-transferase (GST) and glutathione reductase (GR) in viscera were significantly decreased with dietary menadione. However, activities of these enzymes except for GPX in muscle were increased. Therefore, antioxidant responses of abalone were increased in muscle and decreased in viscera by dietary menadione.

Effect of alpha-tocopherol on lipid peroxidation and antioxidant system in fibrosarcoma bearing rats.

PubMed

Vasavi, H; Thangaraju, M; Sachdanandam, P

1994-02-23

The anticarcinogenic activity of alpha-tocopherol (Vitamin E) was tried in fibrosarcoma induced rats through its antioxidative potential. The rate of formation of malondialdehyde (MDA), the end product of lipid peroxidation was analysed in alpha-tocopherol (400 mg/kg body weight) treated and untreated fibrosarcoma bearing rats with respective controls. The levels of non-enzymic antioxidants like, glutathione and vitamin E, and enzymic antioxidants viz., catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GSH-PX), and glutathione-S-transferase (GST) were assayed as well. Significantly increased (p < 0.001) level of lipid peroxide was observed with concomitant decreases in the level of enzymic and non-enzymic antioxidants in fibrosarcoma bearing rats when compared with control animals. In alpha-tocopherol supplemented animals, the corrected level of these parameters were observed likely to near normal values. Thus, alpha-tocopherol can be accepted to pose first line of defense mechanism against excessively formed reactive species due to impaired antioxidant systems in fibrosarcoma conditions, that cause membrane damage leading to deleterious effects.

Protective Effects of Black Rice Extracts on Oxidative Stress Induced by tert-Butyl Hydroperoxide in HepG2 Cells

PubMed Central

Lee, Seon-Mi; Choi, Youngmin; Sung, Jeehye; Kim, Younghwa; Jeong, Heon-Sang; Lee, Junsoo

2014-01-01

Black rice contains many biologically active compounds. The aim of this study was to investigate the protective effects of black rice extracts (whole grain extract, WGE and rice bran extract, RBE) on tert-butyl hydroperoxide (TBHP)-induced oxidative injury in HepG2 cells. Cellular reactive oxygen species (ROS), antioxidant enzyme activities, malondialdehyde (MDA) and glutathione (GSH) concentrations were evaluated as biomarkers of cellular oxidative status. Cells pretreated with 50 and 100 μg/mL of WGE or RBE were more resistant to oxidative stress in a dose-dependent manner. The highest WGE and BRE concentrations enhanced GSH concentrations and modulated antioxidant enzyme activities (glutathione reductase, glutathione-S-transferase, catalase, and superoxide dismutase) compared to TBHP-treated cells. Cells treated with RBE showed higher protective effect compared to cells treated with WGE against oxidative insult. Black rice extracts attenuated oxidative insult by inhibiting cellular ROS and MDA increase and by modulating antioxidant enzyme activities in HepG2 cells. PMID:25580401

Responses of the antioxidative and biotransformation enzymes in the aquatic fungus Mucor hiemalis exposed to cyanotoxins.

PubMed

Balsano, Evelyn; Esterhuizen-Londt, Maranda; Hoque, Enamul; Lima, Stephan Pflugmacher

2017-08-01

To investigate antioxidative and biotransformation enzyme responses in Mucor hiemalis towards cyanotoxins considering its use in mycoremediation applications. Catalase (CAT), glutathione reductase (GR), and glutathione peroxidase (GPx) in M. hiemalis maintained their activities at all tested microcystin-LR (MC-LR) exposure concentrations. Cytosolic glutathione S-transferase (GST) activity decreased with exposure to 100 µg MC-LR l -1 while microsomal GST remained constant. Cylindrospermopsin (CYN) at 100 µg l -1 led to an increase in CAT activity and inhibition of GR, as well as to a concentration-dependent GPx inhibition. Microsomal GST was inhibited at all concentrations tested. β-N-methylamino-L-alanine (BMAA) inhibited GR activity in a concentration-dependent manner, however, CAT, GPx, and GST remained unaffected. M. hiemalis showed enhanced oxidative stress tolerance and intact biotransformation enzyme activity towards MC-LR and BMAA in comparison to CYN, confirming its applicability in bioreactor technology in terms of viability and survival in their presence.

Ameliorative Effects of Chloroform Fraction of Cocos nucifera L. Husk Fiber Against Cisplatin-induced Toxicity in Rats

PubMed Central

Adaramoye, Oluwatosin Adekunle; Azeez, Adesola Fausat; Ola-Davies, Olufunke Elizabeth

2016-01-01

Background: Cisplatin (Cis) is used in the treatment of solid tumors and is known to elicit serious side effects. Objective: The present study investigated the protective effects of chloroform fraction of Cocos nucifera husk fiber (CFCN) against Cis-induced organs’ damage and chromosomal defect in rats. Quercetin (QUE), standard antioxidant, served as positive control. Materials and Methods: Thirty male Wistar rats were assigned into six groups and treated with corn oil (control), Cis alone, Cis + CFCN, CFCN alone, Cis + QUE, and QUE alone. QUE and CFCN were given at 50 and 200 mg/kg/day, respectively, by oral gavage for 7 days before the rats were exposed to a single dose of Cis (10 mg/kg, intraperitoneal) at the last 36 h of study. Results: Administration of Cis alone caused a significant (P < 0.05) increase in the levels of serum creatinine and urea by 72% and 70%, respectively, when compared with the control. The activity of serum aspartate aminotransferase was significantly (P < 0.05) increased while alanine aminotransferase and alkaline phosphatase were insignificantly (P > 0.05) affected in Cis-treated rats. Furthermore, the activities of hepatic and renal catalase, superoxide dismutase, glutathione S-transferase, glutathione peroxidase, and levels of reduced glutathione were significantly (P < 0.05) decreased in Cis-treated rats with concomitant elevation of malondialdehyde. Cis exposure increased the frequency of micro nucleated polychromatic erythrocytes (mPCE) by 92%. Pretreatment with CFCN inhibited lipid peroxidation, enhanced the activities of some antioxidative enzymes and reduced the frequency of mPCE. Conclusions: Chloroform fraction of CFCN may protect against organs damage by Cis. Further studies are required to determine the component of the plant responsible for this activity. SUMMARY Cisplatin (Cis) is used in the treatment of solid tumors and is known to elicit serious side effects. This study investigated the protective effects of chloroform fraction of Cocos nucifera husk fiber (CFCN) against Cis-induced organs’ damage while quercetin (QUE) served as standard antioxidant.Thirty male Wistar rats were assigned into six groups and treated with corn oil (Control), Cis alone, Cis + CFCN, CFCN alone, Cis + QUE and QUE alone.QUE and CFCN were given at 50 and 200 mg/kg/day respectively by oral gavage for seven days before the rats were exposed to a single dose of Cis (10mg/kg, i.p.) at the last 36 h of study. Results indicate that administration of Cis caused a significant (P<0.05) increase in the levels of serum creatinine and urea by 72% and 70% respectively.The activity of serum aspartate aminotransferase was significantly (P <0.05) increased while alanine aminotransferase and alkaline phosphatase were insignificantly (P>0.05) affected in Cis-treated rats.The activities of hepatic and renal catalase, superoxide dismutase, glutathione-s-transferase, glutathione peroxidase and levels of reduced glutathione were significantly (P<0.05) decreased in Cis-treated rats with concomitant elevation of malondialdehyde.Cis exposure increased the frequency of micronucleated polychromatic erythrocytes (mPCE) by 92%.Pretreatment with CFCN inhibited lipid peroxidation, enhanced the activities of some antioxidative enzymes and reduced the frequency of mPCE. The findings suggest that CFCN may protect against organs damage by cisplatin.Further studies are required to determine the component of the plant responsible for this activity. PMID:27034598

The crucial protective role of glutathione against tienilic acid hepatotoxicity in rats

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

Nishiya, Takayoshi; Mori, Kazuhiko; Hattori, Chiharu

2008-10-15

To investigate the hepatotoxic potential of tienilic acid in vivo, we administered a single oral dose of tienilic acid to Sprague-Dawley rats and performed general clinicopathological examinations and hepatic gene expression analysis using Affymetrix microarrays. No change in the serum transaminases was noted at up to 1000 mg/kg, although slight elevation of the serum bile acid and bilirubin, and very mild hepatotoxic changes in morphology were observed. In contrast to the marginal clinicopathological changes, marked upregulation of the genes involved in glutathione biosynthesis [glutathione synthetase and glutamate-cysteine ligase (Gcl)], oxidative stress response [heme oxygenase-1 and NAD(P)H dehydrogenase quinone 1] andmore » phase II drug metabolism (glutathione S-transferase and UDP glycosyltransferase 1A6) were noted after 3 or 6 h post-dosing. The hepatic reduced glutathione level decreased at 3-6 h, and then increased at 24 or 48 h, indicating that the upregulation of NF-E2-related factor 2 (Nrf2)-regulated gene and the late increase in hepatic glutathione are protective responses against the oxidative and/or electrophilic stresses caused by tienilic acid. In a subsequent experiment, tienilic acid in combination with L-buthionine-(S,R)-sulfoximine (BSO), an inhibitor of Gcl caused marked elevation of serum alanine aminotransferase (ALT) with extensive centrilobular hepatocyte necrosis, whereas BSO alone showed no hepatotoxicity. The elevation of ALT by this combination was observed at the same dose levels of tienilic acid as the upregulation of the Nrf2-regulated genes by tienilic acid alone. In conclusion, these results suggest that the impairment of glutathione biosynthesis may play a critical role in the development of tienilic acid hepatotoxicity through extensive oxidative and/or electrophilic stresses.« less

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

Quercetin ameliorates liver injury induced with Tripterygium glycosides by reducing oxidative stress and inflammation.

PubMed

Wang, Junming; Miao, Mingsan; Zhang, Yueyue; Liu, Ruixin; Li, Xaobing; Cui, Ying; Qu, Lingbo

2015-06-01

Quercetin (Que) is one of main compounds in Lysimachia christinae Hance (Christina loosestrife), and has both medicinal and nutritional value. Glycosides from Tripterygium wilfordii Hook.f. (léi gōng téng [the thunder duke vine]; TG) have diverse and broad bioactivities but with a high incidence of liver injury. Our previous study reported on the hepatoprotective properties of an ethanol extract from L. christinae against TG-induced liver injury in mice. This research is designed to observe, for the first time, the possible protective properties of the compound Que against TG-induced liver injury, and the underlying mechanisms that are involved in oxidative stress and anti-inflammation. The results indicated that TG caused excessive elevation in serum levels of alanine/aspartate transaminase (ALT/AST), alkaline phosphatase (ALP), gamma glutamyl transferase (γ-GT), and pro-inflammatory cytokine tumor necrosis factor-alpha (TNF-α), as well as hepatic lipid peroxidation (all P < 0.01). On the other hand, following TG exposure, we observed significantly reduced levels of biomarkers, including hepatic glutathione (GSH), glutathione-S-transferase (GST), glutathione peroxidase (GPx), and the anti-inflammatory cytokine interleukin (IL)-10, as well as the enzyme activity and mRNA expression of copper- and zinc-containing superoxide dismutase (CuZn-SOD) and catalase (CAT) (all P < 0.01). Nevertheless, all of these alterations were reversed by the pre-administration of Que or the drug bifendate (positive control) for 7 consecutive days. Therefore, this study suggests that Que ameliorates TG-induced acute liver injury, probably through its ability to reduce oxidative stress and its anti-inflammatory properties.

Evaluation of the impact of genetic polymorphisms in glutathione-related genes on the association between methylmercury or n-3 polyunsaturated long chain fatty acids and risk of myocardial infarction: a case-control study

PubMed Central

2011-01-01

Background The n-3 polyunsaturated fatty acids eicosapentaenoic acid and docosahexaenoic acid, which are present in fish, are protective against myocardial infarction. However, fish also contains methylmercury, which influences the risk of myocardial infarction, possibly by generating oxidative stress. Methylmercury is metabolized by conjugation to glutathione, which facilitates elimination. Glutathione is also an antioxidant. Individuals with certain polymorphisms in glutathione-related genes may tolerate higher exposures to methylmercury, due to faster metabolism and elimination and/or better glutathione-associated antioxidative capacity. They would thus benefit more from the protective agents in fish, such as eicosapentaenoic+docosahexaenoic acid and selenium. The objective for this study was to elucidate whether genetic polymorphisms in glutathione-related genes modify the association between eicosapentaenoic+docosahexaenoic acid or methylmercury and risk of first ever myocardial infarction. Methods Polymorphisms in glutathione-synthesizing (glutamyl-cysteine ligase catalytic subunit, GCLC and glutamyl-cysteine ligase modifier subunit, GCLM) or glutathione-conjugating (glutathione S-transferase P, GSTP1) genes were genotyped in 1027 individuals from northern Sweden (458 cases of first-ever myocardial infarction and 569 matched controls). The impact of these polymorphisms on the association between erythrocyte-mercury (proxy for methylmercury) and risk of myocardial infarction, as well as between plasma eicosapentaenoic+docosahexaenoic acid and risk of myocardial infarction, was evaluated by conditional logistic regression. The effect of erythrocyte-selenium on risk of myocardial infarction was also taken into consideration. Results There were no strong genetic modifying effects on the association between plasma eicosapentaenoic+docosahexaenoic acid or erythrocyte-mercury and risk of myocardial infarction risk. When eicosapentaenoic+docosahexaenoic acid or erythrocyte-mercury were divided into tertiles, individuals with GCLM-588 TT genotype displayed a lower risk relative to the CC genotype in all but one tertile; in most tertiles the odds ratio was around 0.5 for TT. However, there were few TT carriers and the results were not statistically significant. The results were similar when taking plasma eicosapentaenoic+docosahexaenoic acid, erythrocyte-selenium and erythrocyte-mercury into account simultaneously. Conclusions No statistically significant genetic modifying effects were seen for the association between plasma eicosapentaenoic+docosahexaenoic acid or erythrocyte-mercury and risk of myocardial infarction. Still, our results indicate that the relatively rare GCLM-588 TT genotype may have an impact, but a larger study is necessary for confirmation. PMID:21504558

Anticancer activity of Cynodon dactylon L. root extract against diethyl nitrosamine induced hepatic carcinoma.

PubMed

Kowsalya, R; Kaliaperumal, Jagatheesh; Vaishnavi, M; Namasivayam, Elangovan

2015-01-01

Hepatocellular carcinoma is one of the most common cancers and a lethal disease. In view of the limited treatment and a grave prognosis of liver cancer, preventive control has been emphasized. The methanolic extract of roots of Cynodon dactylon was screened for its hepato-protective activity in diethyl nitrosamine (DEN) induced liver cancer in Swiss albino mice. The plant extract at a dose of 50 mg/kg was administered orally once a week, up to 30 days after DEN administration. The animals were sacrificed; blood sample and liver tissue were collected and used for enzyme assay such as, asparatate amino transferase (AST), alanine aminotransferase (ALT), catalase (CAT), glutathione peroxidase (GPx) and glutathione-S-transferase (GST). The liver marker enzymes AST and ALT produced significant results in the protective action. The antioxidant enzyme assay results concerning the improved activity of GPx, GST and CAT. These results concluded that enhanced levels of antioxidant enzyme and reduced amount of serum amino transaminase, which are suggested to be the major mechanisms of C. dactylon root extract in protecting the mice from hepatocarcinoma induced by DEN. These biochemical observations were supplemented by histopathological examination of liver sections. The methanolic extract of C. dactylon possesses significant anticancer properties.

Nuclear Shield: A Multi-Enzyme Task-Force for Nucleus Protection

PubMed Central

Pallottini, Valentina; Canuti, Lorena; De Canio, Michele; Urbani, Andrea; Marzano, Valeria; Cornetta, Tommaso; Stano, Pasquale; Giovanetti, Anna; Stella, Lorenzo; Canini, Antonella; Federici, Giorgio; Ricci, Giorgio

2010-01-01

Background In eukaryotic cells the nuclear envelope isolates and protects DNA from molecules that could damage its structure or interfere with its processing. Moreover, selected protection enzymes and vitamins act as efficient guardians against toxic compounds both in the nucleoplasm and in the cytosol. The observation that a cytosolic detoxifying and antioxidant enzyme i.e. glutathione transferase is accumulated in the perinuclear region of the rat hepatocytes suggests that other unrecognized modalities of nuclear protection may exist. Here we show evidence for the existence of a safeguard enzyme machinery formed by an hyper-crowding of cationic enzymes and proteins encompassing the nuclear membrane and promoted by electrostatic interactions. Methodology/Principal Findings Electron spectroscopic imaging, zeta potential measurements, isoelectrofocusing, comet assay and mass spectrometry have been used to characterize this surprising structure that is present in the cells of all rat tissues examined (liver, kidney, heart, lung and brain), and that behaves as a “nuclear shield”. In hepatocytes, this hyper-crowding structure is about 300 nm thick, it is mainly formed by cationic enzymes and the local concentration of key protection enzymes, such as glutathione transferase, catalase and glutathione peroxidase is up to seven times higher than in the cytosol. The catalytic activity of these enzymes, when packed in the shield, is not modified and their relative concentrations vary remarkably in different tissues. Removal of this protective shield renders chromosomes more sensitive to damage by oxidative stress. Specific nuclear proteins anchored to the outer nuclear envelope are likely involved in the shield formation and stabilization. Conclusions/Significance The characterization of this previously unrecognized nuclear shield in different tissues opens a new interesting scenario for physiological and protection processes in eukaryotic cells. Selection and accumulation of protection enzymes near sensitive targets represents a new safeguard modality which deeply differs from the adaptive response which is based on expression of specific enzymes. PMID:21170318

The glutathione defense system in the pathogenesis of rheumatoid arthritis.

PubMed

Hassan, M Q; Hadi, R A; Al-Rawi, Z S; Padron, V A; Stohs, S J

2001-01-01

In order to assess a possible role of the natural glutathione defense system in the pathogenesis of rheumatoid arthritis (RA), serum reduced glutathione levels (GSH), glutathione reductase (GSR), glutathione S-transferase (GST), glutathione peroxidase (GSH-Px) and alkaline phosphatase (ALP) activities, lipid peroxidation (MDA content) and indexes of inflammation were evaluated in 58 rheumatic patients. Rheumatoid athritis was associated with significant depletion (ca. 50%) in GSH levels compared with normal control subjects. Serum levels of the detoxifying enzymes GSR and GSH-Px decreased by ca. 50% and 45%, respectively, whereas a threefold increase in the activity of GST was observed. A 1.2-fold increase in ALP was observed in patients with RA. These effects were accompanied by a 3.1-fold increase in serum MDA content. The MDA content was higher in RA patients who were seropositive for rheumatoid factor as well as positive for C-reactive proteins. The erythrocyte sedimentation rate for all patients with RA was approximately 13.8-fold higher than for the control group, and was higher among RA patients who were positive for C-reactive proteins and exhibited seropositivity for rheumatoid factor. Patients with RA receiving gold therapy exhibited significantly lower MDA levels whereas all other factors that were measured were not effected. The results support a hypothesis that defense mechanisms against reactive oxygen species are impaired in RA. Copyright 2001 John Wiley & Sons, Ltd.

Nitric oxide alleviates aluminum-induced oxidative damage through regulating the ascorbate-glutathione cycle in roots of wheat.

PubMed

Sun, Chengliang; Liu, Lijuan; Yu, Yan; Liu, Wenjing; Lu, Lingli; Jin, Chongwei; Lin, Xianyong

2015-06-01

The possible association with nitric oxide (NO) and ascorbate-glutathione (AsA-GSH) cycle in regulating aluminum (Al) tolerance of wheat (Triticum aestivum L.) was investigated using two genotypes with different Al resistance. Exposure to Al inhibited root elongation, and triggered lipid peroxidation and oxidation of AsA to dehydroascorbate and GSH to glutathione disulfide in wheat roots. Exogenous NO significantly increased endogenous NO levels, and subsequently alleviated Al-induced inhibition of root elongation and oxidation of AsA and GSH to maintain the redox molecules in the reduced form in both wheat genotypes. Under Al stress, significantly increased activities and gene transcriptional levels of ascorbate peroxidase, glutathione reductase, and dehydroascorbate reductase, were observed in the root tips of the Al-tolerant genotype Jian-864. Nitric oxide application enhanced the activity and gene transcriptional level of these enzymes in both wheat genotypes. γ-Glutamylcysteine synthetase was not significantly affected by Al or NO, but NO treatments increased the activity of glutathione peroxidase and glutathione S-transferase to a greater extent than the Al-treated wheat seedlings. Proline was significantly decreased by Al, while it was not affected by NO. These results clearly suggest that NO protects wheat root against Al-induced oxidative stress, possibly through its regulation of the AsA-GSH cycle. © 2014 Institute of Botany, Chinese Academy of Sciences.

An integrated biomarker response index for the mussel Mytilus edulis based on laboratory exposure to anthracene and field transplantation experiments

NASA Astrophysics Data System (ADS)

Yuan, Mengqi; Wang, You; Zhou, Bin; Jian, Xiaoyang; Dong, Wenlong; Tang, Xuexi

2017-09-01

Organic pollution is a serious environmental problem in coastal areas and it is important to establish quantitative methods for monitoring this pollution. This study screened a series of sensitive biomarkers to construct an integrated biomarker response (IBR) index using Mytilus edulis. Mussels were exposed to the polycyclic aromatic hydrocarbon anthracene under controlled laboratory conditions and the activities of components of the glutathione antioxidant system, and the concentrations of oxidative-damage markers, were measured in the gills and digestive glands. Anthracene exposure resulted in increased levels of malondialdehyde (MDA) and superoxide radicals (O 2 • ), indicating that oxidative damage had occurred. Correspondingly, anthracene exposure induced increased activities of glutathione S-transferase (GST), glutathione peroxidase (GPx) and reduced glutathione (GSH) in digestive glands, and GPx and glutathione reductase (GR) in gills, consistent with stimulation of the antioxidant system. A field experiment was set up, in which mussels from a relatively clean area were transplanted to a contaminated site. One month later, the activities of GST, GPx and GR had increased in several tissues, particularly in the digestive glands. Based on the laboratory experiment, an IBR, which showed a positive relationship with anthracene exposure, was constructed. The IBR is suggested to be a potentially useful tool for assessing anthracene pollution.

Antioxidant and Protective Effect of Ethyl Acetate Extract of Podophyllum Hexandrum Rhizome on Carbon Tetrachloride Induced Rat Liver Injury

PubMed Central

Ganie, Showkat Ahmad; Haq, Ehtishamul; Masood, Akbar; Hamid, Abid; Zargar, Mohmmad Afzal

2011-01-01

The antioxidant and hepatoprotective activities of ethyl acetate extract was carefully investigated by the methods of DPPH radical scavenging activity, Hydroxyl radical scavenging activity, Superoxide radical scavenging activity, Hydrogen peroxide radical scavenging activity and its Reducing power ability. All these in vitro antioxidant activities were concentration dependent which were compared with standard antioxidants such as BHT, α-tocopherol. The hepatoprotective potential of Podophyllum hexandrum extract was also evaluated in male Wistar rats against carbon tetrachloride (CCl4)-induced liver damage. Pre-treated rats were given ethyl acetate extract at 20, 30 and 50 mg/kg dose prior to CCl4 administration (1 ml/kg, 1:1 in olive oil). Rats pre-treated with Podophyllum hexandrum extract remarkably prevented the elevation of serum AST, ALT, LDH and liver lipid peroxides in CCl4-treated rats. Hepatic glutathione levels were significantly increased by the treatment with the extract in all the experimental groups. The extract at the tested doses also restored the levels of liver homogenate enzymes (glutathione peroxidase, glutathione reductase, superoxide dismutase and glutathione-S- transferase) significantly. This study suggests that ethyl acetate extract of P. hexandrum has a liver protective effect against CCl4-induced hepatotoxicity and possess in vitro antioxidant activities. PMID:21394192

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 from reactive oxygen species (ROS) in response to Al stress in L. usitatissimum. Thus, GSTs and UGTs, probably, play an important role in the response of flax to Al via detoxification of ROS and cell wall modification. PMID:28066475

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.

Glycogen debranching enzyme 6 (AGL), enolase 1 (ENOSF1), ectonucleotide pyrophosphatase 2 (ENPP2_1), glutathione S-transferase 3 (GSTM3_3) and mannosidase (MAN2B2) metabolism computational network analysis between chimpanzee and human left cerebrum.

PubMed

Sun, Lingjun; Wang, Lin; Jiang, Minghu; Huang, Juxiang; Lin, Hong

2011-12-01

We identified significantly higher expression of the genes glycogen debranching enzyme 6 (AGL), enolase 1 (ENOSF1), ectonucleotide pyrophosphatase 2 (ENPP2_1), glutathione S-transferase 3 (GSTM3_3) and mannosidase (MAN2B2) from human left cerebrums versus chimpanzees. Yet the distinct low- and high-expression AGL, ENOSF1, ENPP2_1, GSTM3_3 and MAN2B2 metabolism networks between chimpanzee and human left cerebrum remain to be elucidated. Here, we constructed low- and high-expression activated and inhibited upstream and downstream AGL, ENOSF1, ENPP2_1, GSTM3_3 and MAN2B2 metabolism network between chimpanzee and human left cerebrum in GEO data set by gene regulatory network inference method based on linear programming and decomposition procedure, under covering AGL, ENOSF1, ENPP2_1, GSTM3_3 and MAN2B2 pathway and matching metabolism enrichment analysis by CapitalBio MAS 3.0 integration of public databases, including Gene Ontology, KEGG, BioCarta, GenMapp, Intact, UniGene, OMIM, etc. Our results show that the AGL, ENOSF1, ENPP2_1, GSTM3_3 and MAN2B2 metabolism network has more activated and less inhibited molecules in chimpanzee, but less activated and more inhibited in the human left cerebrum. We inferred stronger carbohydrate, glutathione and proteoglycan metabolism, ATPase activity, but weaker base excision repair, arachidonic acid and drug metabolism as a result of inducing cell growth in low-expression AGL, ENOSF1, ENPP2_1, GSTM3_3 and MAN2B2 metabolism network of chimpanzee left cerebrum; whereas stronger lipid metabolism, amino acid catabolism, DNA repair but weaker inflammatory response, cell proliferation, glutathione and carbohydrate metabolism as a result of inducing cell differentiation in high-expression AGL, ENOSF1, ENPP2_1, GSTM3_3 and MAN2B2 metabolism network of human left cerebrum. Our inferences are consistent with recent reports and computational activation and inhibition gene number patterns, respectively.

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.

Modification and translocation of Rac/Rop guanosine 5'-triphosphate-binding proteins of Scoparia dulcis in response to stimulation with methyl jasmonate.

PubMed

Mitamura, Toshiaki; Yamamura, Yoshimi; Kurosaki, Fumiya

2011-01-01

Translocation of two Rac/Rop guanosine 5'-triphosphate-binding proteins from Scoparia dulcis, Sdrac-1 and Sdrac-2, was examined employing transformed belladonna which overproduces these proteins as glutathione-S-transferase-tagged forms. The transferase activities of the fused proteins in microsomal fraction of belladonna markedly increased by the incubation with methyl jasmonate either in Sdrac-1 or Sdrac-2 transformant, while low and constant activities were observed in the untreated control. Recombinant Sdrac-2 protein was found to bind to prenyl chain in the presence of cell extracts prepared from methyl jasmonate-treated S. dulcis, however, Sdrac-1 was palmitoylated by the addition of the cell extracts. These results suggest that both Sdrac-1 and Sdrac-2 translocate to plant membranes by the stimulation with methyl jasmonate, however, targeting of these proteins is triggered by the independent modification mechanisms, palmitoylation for Sdrac-1 and prenylation for Sdrac-2.

Hepatoprotective activity of Sonchus asper against carbon tetrachloride-induced injuries in male rats: a randomized controlled trial

PubMed Central

2012-01-01

Abstract Background Sonchus asper (SAME) is used as a folk medicine in hepatic disorders. In this study, the hepatoprotective effects of the methanol extract of SAME was evaluated against carbon tetrachloride (CCl4)-induced liver injuries in rats. Methods To evaluate the hepatoprotective effects of SAME, 36 male Sprague–Dawley rats were equally divided into 6 groups. Rats of Group I (control) were given free access to approved feed and water. Rats of Group II were injected intraperitoneally with CCl4 (3 ml/kg) as a 30% solution in olive oil (v/v) twice a week for 4 weeks. Animals of Groups III (100 mg/kg) and IV (200 mg/kg) received SAME, whereas those of Group V were given silymarin via gavage (100 mg/kg) after 48 h of CCl4 treatment. Group VI received SAME (200 mg/kg) twice a week for 4 weeks without CCl4 treatment. Various parameters, such as the serum enzyme levels, serum biochemical marker levels, antioxidant enzyme activities, and liver histopathology were used to estimate the hepatoprotective efficacy of SAME. Results The administration of SAME and silymarin significantly lowered the CCl4-induced serum levels of hepatic marker enzymes (aspartate aminotransferase, alanine aminotransferase, and lactate dehydrogenase), cholesterol, low-density lipoprotein, and triglycerides while elevating high-density lipoprotein levels. The hepatic contents of glutathione and activities of catalase, superoxide dismutase, glutathione peroxidase, glutathione S-transferase, and glutathione reductase were reduced. The levels of thiobarbituric acid-reactive substances that were increased by CCl4 were brought back to control levels by the administration of SAME and silymarin. Liver histopathology showed that SAME reduced the incidence of hepatic lesions induced by CCl4 in rats. Conclusion SAME may protect the liver against CCl4-induced oxidative damage in rats. PMID:22776436

Menadione stress in Saccharomyces cerevisiae strains deficient in the glutathione transferases.

PubMed

Castro, F A V; Herdeiro, R S; Panek, A D; Eleutherio, E C A; Pereira, M D

2007-02-01

Using S. cerevisiae as a eukaryotic cell model we have analyzed the involvement of both glutathione transferase isoforms, Gtt1 and Gtt2, in constitutive resistance and adaptive response to menadione, a quinone which can exert its toxicity as redox cycling and/or electrophiles. The detoxification properties, of these enzymes, have also been analyzed by the appearance of S-conjugates in the media. Direct exposure to menadione (20 mM/60 min) showed to be lethal for cells deficient on both Gtt1 and Gtt2 isoforms. However, after pre-treatment with a low menadione concentration, cells deficient in Gtt2 displayed reduced ability to acquire tolerance when compared with the control and the Gtt1 deficient strains. Analyzing the toxic effects of menadione we observed that the gtt2 mutant showed no reduction in lipid peroxidation levels. Moreover, measuring the levels of intracellular oxidation during menadione stress we have shown that the increase of this oxidative stress parameter was due to the capacity menadione possesses in generating reactive oxygen species (ROS) and that both GSH and Gtt2 isoform were required to enhance ROS production. Furthermore, the efflux of the menadione-GSH conjugate, which is related with detoxification of xenobiotic pathways, was not detected in the gtt2 mutant. Taken together, these results suggest that acquisition of tolerance against stress generated by menadione and the process of detoxification through S-conjugates are dependent upon Gtt2 activity. This assessment was corroborated by the increase of GTT2 expression, and not of GTT1, after menadione treatment.

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.

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.

Association of Angiotensin-Converting Enzyme and Glutathione S-Transferase Gene Polymorphisms with Body Mass Index among Hypertensive North Indians

PubMed Central

Rizvi, Saliha; Raza, Syed T.; Siddiqi, Zeba; Abbas, Shania; Mahdi, Farzana

2015-01-01

Objectives: This study aimed to examine the association of angiotensin-converting enzyme (ACE) and glutathione S-transferase (GST) gene polymorphisms with body mass index (BMI) in hypertensive North Indians. Methods: This case-control study was carried out between May 2013 and November 2014 at the Era’s Lucknow Medical College & Hospital, Lucknow, India, and included 378 subjects divided into three groups. One group constituted 253 hypertensive individuals (sustained diastolic blood pressure of >90 mmHg and systolic blood pressure of >140 mmHg) who were subcategorised according to normal (<25 kg/m2) or high (≥25 kg/m2) BMI. The third group consisted of 125 age-, gender- and ethnically-matched normotensive controls with a normal BMI. Gene polymorphisms were evaluated by polymerase chain reaction. The genotypic and allelic frequency distribution among both groups were analysed. Results: A significant difference was found between GST theta 1-null and GST mu 1-positive genotype frequencies among the hypertensive overweight/obese individuals and controls (P = 0.014 and 0.033, respectively). However, no difference was observed in the frequency of ACE polymorphisms. ACE insertion/insertion genotype (P = 0.006), insertion and deletion alleles (P = 0.007 each) and GST theta 1-null and GST theta 1-positive genotypes (P = 0.006 each) were found to differ significantly between hypertensive cases and controls, regardless of BMI. Conclusion: ACE and GST gene polymorphisms were not associated with BMI but were significantly associated with hypertension among the studied group of North Indians. PMID:26629373

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 age, schistosome infection status and PZQ treatment affect the cellular cytokine response to GST. Thus the efficacy of a GST-based vaccine may also be shaped by the demographic and epidemiological characteristics of targeted populations. PMID:24810615

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.

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

Microbial community induces a plant defense system under growing on the lunar regolith analogue

NASA Astrophysics Data System (ADS)

Zaetz, Irina; Mytrokhyn, Olexander; Lukashov, Dmitry; Mashkovska, Svitlana; Kozyrovska, Natalia; Foing, Bernard H.

The lunar rock considered as a potential source of chemical elements essential for plant nutrition, however, this substrate is of a low bioavailability. The use of microorganisms for decomposition of silicate rocks and stimulation of plant growth is a key idea in precursory scenario of growing pioneer plants for a lunar base (Kozyrovska et al., 2004; 2006; Zaetz et al., 2006). In model experiments a consortium of well-defined plant-associated bacteria were used for growing of French marigold (Tagetes patula L.) in anorthosite, analogous to a lunar rock. Inoculated plants appeared better seed germination, more fast development and also increased accumulation of K, Mg, Mn, Co, Cu and lowered level of the toxic Zn, Ni, Cr, comparing to control tagetes'. Bacteria regulate metal homeostasis in plants by changing their bioavailability and by stimulating of plant defense mechanisms. Inoculated plants were being accommodated to growth under stress conditions on anorthosite used as a substrate. In contrast, control plants manifested a heavy metal-induced oxidative stress, as quantified by protein carbonyl accumulation. Depending on the plant organ sampled and developmental stage there were increases or loses in the antioxidant enzyme activities (guaiacol peroxidase and glutathione-S-transferase). These changes were most evident in inoculated plants. Production of phenolic compounds, known as antioxidants and heavy metal chelators, is rised in variants of inoculated marigolds. Guaiacol peroxidase plays the main role, finally, in a reducing toxicity of heavy metals in plant leaves, while glutathione-S-transferase and phenolics overcome stress in roots.

Atypical localization of the oligodendrocytic isoform (PI) of glutathione-S-transferase in astrocytes during cuprizone intoxication.

PubMed

Cammer, W; Zhang, H

1993-10-01

Immunocytochemical staining for the Pi and Mu isoforms of glutathione-S-transferase was used to investigate changes in the glial cells in the mouse forebrain. During early development in mouse forebrains the localizations of carbonic anhydrase, Pi and Mu were similar to the respective cellular localizations that had been observed in neonatal rat brain. That is, Pi was found in oligodendrocyte precursors, Mu in astrocytes, and carbonic anhydrase in both oligodendrocyte precursors and astrocytes. In forebrains of 6-week-old mice the neurotoxicant, cuprizone, induced oligodendrocyte degeneration, gliosis, and partial demyelination. Degeneration, gliosis, and partial demyelination. Degeneration of oligodendrocytes, and astrocytosis, began during the initial week of cuprizone feeding, and by the end of the eighth week some demyelination was observed. After mice were fed cuprizone for 4 to 7 weeks, Pi appeared in some of the reactive astrocytes, and Pi-positive astrocytes were present for at least 7 additional weeks. Normally, Pi appeared only in oligodendrocytes. Very few Pi-positive oligodendrocytes remained after the second week. During the eighth week healthy-looking carbonic anhydrase-positive oligodendrocytes reappeared and began to accumulate, and a few small patches of Pi-positive oligodendrocytes were also observed. In summary, some novel findings about glial cells were the observation of an enzyme (Pi) that is lost earlier from oligodendrocytes than is carbonic anhydrase, the apparently unique shift in Pi expression from oligodendrocytes to astrocytes and the greater temporal dissociation between loss of oligodendrocytes and demyelination in the older mice.

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.

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.

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.

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.

Matrin 3 co-immunoprecipitates with the heat shock proteins glucose-regulated protein 78 (GRP78), GRP75 and glutathione S-transferase π isoform 2 (GSTπ2) in thymoma cells.

PubMed

Osman, Ahmed M; van Loveren, Henk

2014-06-01

Here, we report evidence that matrin 3 (MATR3), a highly conserved inner nuclear matrix phosphoprotein, whose function is largely unknown, interacts specifically with the heat shock proteins glucose-regulated protein 78 (GRP78), GRP75 and glutathione S-transferase π isoform 2 (GSTπ2). Using immunoprecipitation experiments of lysates obtained from control and tributyltin oxide (TBTO)-treated thymoma cell line (EL4), we identified MATR3 and its partners by MS/MS analysis and confirmed by immunoblot. We also show that MATR3 undergoes degradation as reported before and that this cleavage process, which is inhibited by the broad-spectrum caspase inhibitor, z-VAD-FMK, is more marked in TBTO-treated cells. Further, we found that the heat shock protein glucose-regulated protein 78 was downregulated in the TBTO-treated cells. The GRP78 protein is known to protect cells from apoptosis by complexing with procaspase 7 thereby preventing caspase activation cascade. By immunoblot analysis, we found that the levels of procaspases-3 and -7 were lower in TBTO-treated cells; in contrast, the level of p20, the active form of caspase 3, was relatively higher in the treated cells compared to that of control cells. We propose that the TBTO-mediated downregulation of GRP78 triggers the caspase cascade pathway leading to MATR3 degradation. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

Identification of aldo-keto reductase (AKR7A1) and glutathione S-transferase pi (GSTP1) as novel renal damage biomarkers following exposure to mercury.

PubMed

Shin, Y-J; Kim, K-A; Kim, E-S; Kim, J-H; Kim, H-S; Ha, M; Bae, O-N

2017-01-01

The kidney is one of the main targets for toxicity induced by xenobiotics. Sensitive detection of early impairment is critical to assess chemical-associated renal toxicity. The aim of this study was to identify potential nephrotoxic biomarkers in rat kidney tissues after exposure to mercury (Hg), a representative nephrotoxicant, and to evaluate these new biomarkers employing in vivo and in vitro systems. Mercuric chloride was administered orally to Sprague-Dawley rats for 2 weeks. Proteomic analysis revealed that aldo-keto reductase (AKR7A1) and glutathione S-transferase pi (GSTP1) were significantly elevated in kidney after Hg exposure. While the levels of conventional nephrotoxic clinical markers including blood urea nitrogen and serum creatinine were not elevated, the mRNA and protein levels of AKR7A1 and GSTP1 were increased upon Hg exposure in a dose-dependent manner. The increases in AKR7A1 and GSTP1 were also observed in rat kidneys after an extended exposure for 6 weeks to low-dose Hg. In in vitro rat kidney proximal tubular cells, changes in AKR7A1 and GSTP1 levels correlated well with the extent of cytotoxicity induced by Hg, cadmium, or cisplatin. AKR7A1 and GSTP1 were identified as new candidates for Hg-induced nephrotoxicity, suggesting that these biomarkers have potential for evaluating or predicting nephrotoxicity.

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

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.

Induction of the pi class of glutathione S-transferase by carnosic acid in rat Clone 9 cells via the p38/Nrf2 pathway.

PubMed

Lin, Chia-Yuan; Wu, Chi-Rei; Chang, Shu-Wei; Wang, Yu-Jung; Wu, Jia-Jiuan; Tsai, Chia-Wen

2015-06-01

Induction of phase II enzymes is important in cancer chemoprevention. We compared the effect of rosemary diterpenes on the expression of the pi class of glutathione S-transferase (GSTP) in rat liver Clone 9 cells and the signaling pathways involved. Culturing cells with 1, 5, 10, or 20 μM carnosic acid (CA) or carnosol (CS) for 24 h in a dose-dependent manner increased the GSTP expression. CA was more potent than CS. The RNA level and the enzyme activity of GSTP were also enhanced by CA treatment. Treatment with 10 μM CA highly induced the reporter activity of the enhancer element GPEI. Furthermore, CA markedly increased the translocation of nuclear factor erythroid-2 related factor 2 (Nrf2) from the cytosol to the nucleus after 30 to 60 min. CA the stimulated the protein induction of p38, nuclear Nrf2, and GSTP was diminished in the presence of SB203580 (a p38 inhibitor). In addition, SB203580 pretreatment or silencing of Nrf2 by siRNA suppressed the CA-induced GPEI-DNA binding activity and GSTP protein expression. Knockdown of p38 or Nrf2 by siRNA abolished the activation of p38 and Nrf2 as well as the protein induction and enzyme activity of GSTP by CA. These results suggest that CA up-regulates the expression and enzyme activity of GSTP via the p38/Nrf2/GPEI pathway.

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.

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 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.

Response of glutathione S-transferase Pi (GSTP1) to neoadjuvant therapy in rectal adenocarcinoma.

PubMed

Bedford, M R; Anathhanam, S; Saleh, D; Hickson, A; McGregor, A K; Boyle, K; Burke, D

2012-12-01

The response of rectal adenocarcinoma to neoadjuvant therapy is variable. Accurate prediction of response would enable selective administration of therapy. The enzyme glutathione S-transferase Pi (GSTP1) has been shown to influence response to therapy in some solid tumours. Few data are available for rectal cancer. The GSTP1 levels in rectal adenocarcinoma and adjacent normal mucosa were quantified before and after exposure to neoadjuvant therapy. Venous blood samples and biopsies of normal rectal mucosa and tumour were prospectively obtained from patients with primary rectal cancer. Patients were stratified by exposure to neoadjuvant therapy or surgery alone. GSTP1 was quantitatively measured using an enzyme-linked immunosorbent assay. Ninety-two patients (54 men; median age 68 years) were recruited. The median GSTP1 level was significantly higher in rectal adenocarcinoma than in matched normal mucosa [6.59 μg/mg vs 4.57 μg/mg; P < 0.001]. The median tumour GSTP1 level was significantly lower in the therapy group compared with unmatched samples from the no-therapy group [4.47 μg/mg vs 7.76 μg/mg; P < 0.001]. The GSTP1 level is increased in rectal adenocarcinoma compared with adjacent normal mucosa. It decreases following neoadjuvant therapy. Future studies correlating pre-therapy GSTP1 levels with pathological response would be of interest. © 2012 The Authors. Colorectal Disease © 2012 The Association of Coloproctology of Great Britain and Ireland.

The cellular RNA-binding protein EAP recognizes a conserved stem-loop in the Epstein-Barr virus small RNA EBER 1.

PubMed Central

Toczyski, D P; Steitz, J A

1993-01-01

EAP (EBER-associated protein) is an abundant, 15-kDa cellular RNA-binding protein which associates with certain herpesvirus small RNAs. We have raised polyclonal anti-EAP antibodies against a glutathione S-transferase-EAP fusion protein. Analysis of the RNA precipitated by these antibodies from Epstein-Barr virus (EBV)- or herpesvirus papio (HVP)-infected cells shows that > 95% of EBER 1 (EBV-encoded RNA 1) and the majority of HVP 1 (an HVP small RNA homologous to EBER 1) are associated with EAP. RNase protection experiments performed on native EBER 1 particles with affinity-purified anti-EAP antibodies demonstrate that EAP binds a stem-loop structure (stem-loop 3) of EBER 1. Since bacterially expressed glutathione S-transferase-EAP fusion protein binds EBER 1, we conclude that EAP binding is independent of any other cellular or viral protein. Detailed mutational analyses of stem-loop 3 suggest that EAP recognizes the majority of the nucleotides in this hairpin, interacting with both single-stranded and double-stranded regions in a sequence-specific manner. Binding studies utilizing EBER 1 deletion mutants suggest that there may also be a second, weaker EAP-binding site on stem-loop 4 of EBER 1. These data and the fact that stem-loop 3 represents the most highly conserved region between EBER 1 and HVP 1 suggest that EAP binding is a critical aspect of EBER 1 and HVP 1 function. Images PMID:8380232

Arginine intake is associated with oxidative stress in a general population.

PubMed

Carvalho, Aline Martins de; Oliveira, Antonio Anax Falcão de; Loureiro, Ana Paula de Melo; Gattás, Gilka Jorge Figaro; Fisberg, Regina Mara; Marchioni, Dirce Maria

2017-01-01

The aim of this study was to assess the association between protein and arginine from meat intake and oxidative stress in a general population. Data came from the Health Survey for Sao Paulo (ISA-Capital), a cross-sectional population-based study in Brazil (N = 549 adults). Food intake was estimated by a 24-h dietary recall. Oxidative stress was estimated by malondialdehyde (MDA) concentration in plasma. Analyses were performed using general linear regression models adjusted for some genetic, lifestyle, and biochemical confounders. MDA levels were associated with meat intake (P for linear trend = 0.031), protein from meat (P for linear trend = 0.006), and arginine from meat (P for linear trend = 0.044) after adjustments for confounders: age, sex, body mass index, smoking, physical activity, intake of fruit and vegetables, energy and heterocyclic amines, C-reactive protein levels, and polymorphisms in GSTM1 (glutathione S-transferase Mu 1) and GSTT1 (glutathione S-transferase theta 1) genes. Results were not significant for total protein and protein from vegetable intake (P > 0.05). High protein and arginine from meat intake were associated with oxidative stress independently of genetic, lifestyle, and biochemical confounders in a population-based study. Our results suggested a novel link between high protein/arginine intake and oxidative stress, which is a major cause of age-related diseases. Copyright © 2016 Elsevier Inc. All rights reserved.

Glutathione S-transferase gene polymorphisms in celiac disease and their correlation with genomic instability phenotype.

PubMed

Fundia, Ariela F; Weich, Natalia; Crivelli, Adriana; La Motta, Graciela; Larripa, Irene B; Slavutsky, Irma

2014-06-01

Genomic instability and reduced glutathione S-transferase (GST) activity have been identified as potential risk factors for malignant complications in celiac disease (CD). In this study, we assessed the possible influence of GST polymorphisms on genome instability phenotypes in a genetically characterised group of celiac patients from previous studies. The deletion polymorphisms in GSTM1 and GSTT1 genes and the single-nucleotide polymorphism GSTP1 c.313A>G were genotyped using PCR in a set of 20 untreated adult patients with a known genomic instability phenotype and 69 age- and sex-matched healthy individuals. The frequencies of variant genotypes in patients were GSTM1-null (30%), GSTT1-null (5%), GSTP1-AG (60%) and GSTP1-GG (15%), and they showed no differences from controls. No significant differences were found in the genotype distribution based on telomere length. Cases with GSTM1-null genotype (83%) and microsatellite stability were more frequent than those with genomic instability. Moreover, carriers of GSTP1-variant genotype (73%) and stable phenotype were significantly increased compared to unstable patients (27%) (P=0.031). No differences were found according to the clinical-pathological characteristics of celiac cases. No association between GST polymorphic variants and celiac-associated genomic instability was proven in our cohort. Future studies should explore the usefulness of other biomarkers to distinguish celiac patients who are susceptible to cancer development. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

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

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.

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.

Correlation between Pesticide Resistance and Enzyme Activity in the Diamondback Moth, Plutella xylostella

PubMed Central

Gong, Ya-Jun; Wang, Ze-Hua; Shi, Bao-Cai; Kang, Zong-Jiang; Zhu, Liang; Jin, Gui-Hua; Weig, Shu-Jun

2013-01-01

The diamondback moth, Plutella xylostella (L.) (Lepidoptera: Plutellidae), is one of the most important pests that has developed high pesticide resistance. The resistances of five Chinese populations of this moth, four resistant strains (from Beijing, Henan, Fujian, and Guangdong) and one susceptible strain, to five pesticides were determined, and the activities of carboxylesterase, glutathione S-transferase, and acetylcholine esterase were tested in all five populations. The correlations between pesticide resistance and enzyme activity were analyzed. The results showed that the resistance status to the five pesticides was different among the five populations. The resistance ratios of the Beijing and Henan populations to spinosad were 5.84 and 8.22, respectively, and those to beta-cypermethrin were 4.91 and 4.98, respectively. These ratios were higher than those for the Fujian and Guangdong populations. The Fujian population was more sensitive to abamectin and chlorpyrifos than the susceptible population (the resistance ratios were 0.14 and 0.91, respectively); in fact, the median lethal concentration for P. xylostella was significantly higher for chlorpyrifos than that for any of the other four pesticides. The carboxylesterase activity in P. xylostella showed positive correlations with the resistance to spinosad, beta-cypermethrin, chlorpyrifos, and abamectin, but no correlation was observed between the carboxylesterase activity and resistance to emamectin benzoate, between glutathione S-transferase activity and resistance to any of the five pesticides tested, or between acetylcholine esterase activity and any of the pesticides except for emamectin benzoate. PMID:24766444

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

Trends in detoxification enzymes and heavy metal accumulation in ground beetles (Coleoptera: Carabidae) inhabiting a gradient of pollution.

PubMed

Stone, David; Jepson, Paul; Laskowski, Ryszard

2002-05-01

Non-specfic carboxylesterase and glutathione S-transferase activity was measured in the ground beetle, Pterosthicus oblongopunctatus (Coleoptera: Carabidae), from five sites along a gradient of heavy metal pollution. A previous study determined that beetles from the two most polluted sites (site codes OLK2 and OLK3) were more susceptible to additional stressors compared with beetles from the reference site (Stone et al., Environ. Pollut. 113, 239-244 2001), suggesting the possibility of physiological impairment. Metal body burdens in ground beetles from five sites along the gradient ranged from 79 to 201 microg/g Zn, 0.174 to 8.66 microg/g Pb and 1.14 to 10.8 microg/g Cd, whereas Cu seemed to be efficiently regulated regardless of metal levels in the soil. Beetle mid- and hindguts were homogenized and the soluble fraction containing glutathione S-transferase (GST) and carboxylesterase (CaE) was assayed using kinetic analyses. Significantly higher levels of GST were found only in female beetles from the most polluted sites (OLK2 and OLK3; P=0.049, P<0.001, respectively) compared with the reference site (OLK7). In addition, OLK3 females had significantly higher levels of CaE compared with the reference beetles (P=0.01). Male beetles did not differ in enzyme activity along the metal gradient. Overall, obvious trends in detoxification enzymes were not detected in ground beetles in association with metal body burdens.

Methylated Glutathione S-transferase 1 (mGSTP1) is a potential plasma free DNA epigenetic marker of prognosis and response to chemotherapy in castrate-resistant prostate cancer.

PubMed

Mahon, K L; Qu, W; Devaney, J; Paul, C; Castillo, L; Wykes, R J; Chatfield, M D; Boyer, M J; Stockler, M R; Marx, G; Gurney, H; Mallesara, G; Molloy, P L; Horvath, L G; Clark, S J

2014-10-28

Glutathione S-transferase 1 (GSTP1) inactivation is associated with CpG island promoter hypermethylation in the majority of prostate cancers (PCs). This study assessed whether the level of circulating methylated GSTP1 (mGSTP1) in plasma DNA is associated with chemotherapy response and overall survival (OS). Plasma samples were collected prospectively from a Phase I exploratory cohort of 75 men with castrate-resistant PC (CRPC) and a Phase II independent validation cohort (n=51). mGSTP1 levels in free DNA were measured using a sensitive methylation-specific PCR assay. The Phase I cohort identified that detectable baseline mGSTP1 DNA was associated with poorer OS (HR, 4.2 95% CI 2.1-8.2; P<0.0001). A decrease in mGSTP1 DNA levels after cycle 1 was associated with a PSA response (P=0.008). In the Phase II cohort, baseline mGSTP1 DNA was a stronger predictor of OS than PSA change after 3 months (P=0.02). Undetectable plasma mGSTP1 after one cycle of chemotherapy was associated with PSA response (P=0.007). We identified plasma mGSTP1 DNA as a potential prognostic marker in men with CRPC as well as a potential surrogate therapeutic efficacy marker for chemotherapy and corroborated these findings in an independent Phase II cohort. Prospective Phase III assessment of mGSTP1 levels in plasma DNA is now warranted.

Basic Principles and Emerging Concepts in the Redox Control of Transcription Factors

PubMed Central

Flohé, Leopold

2011-01-01

Abstract Convincing concepts of redox control of gene transcription have been worked out for prokaryotes and lower eukaryotes, whereas the knowledge on complex mammalian systems still resembles a patchwork of poorly connected findings. The article, therefore, reviews principles of redox regulation with special emphasis on chemical feasibility, kinetic requirements, specificity, and physiological context, taking well investigated mammalian transcription factor systems, nuclear transcription factor of bone marrow-derived lymphocytes (NF-κB), and kelch-like ECH-associated protein-1 (Keap1)/Nrf2, as paradigms. Major conclusions are that (i) direct signaling by free radicals is restricted to O2•− and •NO and can be excluded for fast reacting radicals such as •OH, •OR, or Cl•; (ii) oxidant signals are H2O2, enzymatically generated lipid hydroperoxides, and peroxynitrite; (iii) free radical damage is sensed via generation of Michael acceptors; (iv) protein thiol oxidation/alkylation is the prominent mechanism to modulate function; (v) redox sensors must be thiol peroxidases by themselves or proteins with similarly reactive cysteine or selenocysteine (Sec) residues to kinetically compete with glutathione peroxidase (GPx)- and peroxiredoxin (Prx)-type peroxidases or glutathione-S-transferases, respectively, a postulate that still has to be verified for putative mammalian sensors. S-transferases and Prxs are considered for system complementation. The impact of NF-κB and Nrf2 on hormesis, management of inflammatory diseases, and cancer prevention is critically discussed. Antioxid. Redox Signal. 15, 2335–2381. PMID:21194351

Genetic Variation in Glutathione-Related Genes and Body Burden of Methylmercury

PubMed Central

Engström, Karin Schläwicke; Strömberg, Ulf; Lundh, Thomas; Johansson, Ingegerd; Vessby, Bengt; Hallmans, Göran; Skerfving, Staffan; Broberg, Karin

2008-01-01

Background Exposure to toxic methylmercury (MeHg) through fish consumption is a large problem worldwide, and it has led to governmental recommendations of reduced fish consumption and blacklisting of mercury-contaminated fish. The elimination kinetics of MeHg varies greatly among individuals. Knowledge about the reasons for such variation is of importance for improving the risk assessment for MeHg. One possible explanation is hereditary differences in MeHg metabolism. MeHg is eliminated from the body as a glutathione (GSH) conjugate. Objectives We conducted this study to assess the influence of polymorphisms in GSH-synthesizing [glutamyl-cysteine ligase modifier subunit (GCLM-588) and glutamyl-cysteine ligase catalytic subunit (GCLC-129)] or GSH-conjugating [glutathione S-transferase pi 1 (GSTP1–105 and GSTP1–114)] genes on MeHg retention. Methods Based on information obtained from questionnaires, 292 subjects from northern Sweden had a high consumption of fish (lean/fat fish two to three times per week or more). We measured total Hg in erythrocytes (Ery-Hg) and long-chain n-3 polyunsaturated fatty acids in plasma (P-PUFA; an exposure marker for fish intake). Results The GSTP1 genotype modified Ery-Hg; effects were seen for GSTP1–105 and −114 separately, and combining them resulted in stronger effects. We found evidence of effect modification: individuals with zero or one variant allele demonstrated a steeper regression slope for Ery-Hg (p = 0.038) compared with individuals with two or more variant alleles. The GCLM-588 genotype also influenced Ery-Hg (p = 0.035): Individuals with the GCLM-588 TT genotype demonstrated the highest Ery-Hg, but we saw no evidence of effect modification with increasing P-PUFA. Conclusions These results suggest a role of GSH-related polymorphisms in MeHg metabolism. PMID:18560528

Limiting prolonged inflammation during proliferation and remodeling phases of wound healing in streptozotocin-induced diabetic rats supplemented with camel undenatured whey protein

PubMed Central

2013-01-01

Background Impaired diabetic wound healing occurs as a consequence of excessive reactive oxygen species (ROS) and inflammatory cytokine production. We previously found that whey protein (WP) was able to normally regulate the ROS and inflammatory cytokines during the inflammatory phase (first day) in streptozotocin (STZ)-diabetic wound healing. This study was designed to assess the effect of WP on metabolic status, the inflammation and anti-inflammation response, oxidative stress and the antioxidant defense system during different phases of the wound healing process in diabetic rats. WP at a dosage of 100 mg/kg of body weight, dissolved in 1% CMC, was orally administered daily to wounded normal (non-diabetic) and STZ-induced diabetic rats for 8 days starting from the 1st day after wounding. Results The data revealed that WP enhanced wound closure and was associated with an increase in serum insulin levels in diabetic rats and an alleviation of hyperglycemic and hyperlipidemic states in diabetic animals. The increase in insulin levels as a result of WP administration is associated with a marked multiplication of β-cells in the core of islets of Langerhans. WP induced a reduction in serum TNF-α, IL-1β and IL-6 levels and an increase in IL-10 levels, especially on the 4th day after wounding and treatment. WP also suppressed hepatic lipid peroxidation and stimulated the antioxidant defense system by increasing the level of glutathione and the activity of glutathione-S-transferase, glutathione peroxidase and superoxide dismutase (SOD) in wounded diabetic rats. Conclusions WP was observed to enhance wound closure by improving the diabetic condition, limiting prolonged inflammation, suppressing oxidative stress and elevating the antioxidant defense system in diabetic rats. PMID:23883360

Inhibition of hematopoietic prostaglandin D2 Synthase (H-PGDS) by an alkaloid extract from Combretum molle

PubMed Central

2014-01-01

Background Hematopoietic prostaglandin D2 synthase (H-PGDS, GST Sigma) is a member of the glutathione S-transferase super family of enzymes that catalyses the conjugation of electrophilic substances with reduced glutathione. The enzyme catalyses the conversion of PGH2 to PGD2 which mediates inflammatory responses. The inhibition of H-PGDS is of importance in alleviating damage to tissues due to unwarranted synthesis of PGD2. Combretum molle has been used in African ethno medicinal practices and has been shown to reduce fever and pain. The effect of C. molle alkaloid extract on H-PGDS was thus, investigated. Methods H-PGDS was expressed in Escherichia coli XL1-Blue cells and purified using nickel immobilized metal affinity chromatography. The effect of C. molle alkaloid extract on H-PGDS activity was determined with 1-chloro-2, 4-dinitrobenzene (CDNB) as substrate. The effect of C. molle alkaloid extract with time on H-PGDS was determined. The mechanism of inhibition was then investigated using CDNB and glutathione (GSH) as substrates. Results A specific activity of 24 μmol/mg/min was obtained after H-PGDS had been purified. The alkaloid extract exhibited a 70% inhibition on H-PGDS with an IC50 of 13.7 μg/ml. C. molle alkaloid extract showed an uncompetitive inhibition of H-PGDS with Ki = 41 μg/ml towards GSH, and non-competitive inhibition towards CDNB with Ki = 7.7 μg/ml and Ki′ = 9.2 μg/ml. Conclusion The data shows that C. molle alkaloid extract is a potent inhibitor of H-PGDS. This study thus supports the traditional use of the plant for inflammation. PMID:24996417

Evaluation of plasma, erythrocytes, and bronchoalveolar lavage fluid antioxidant defense system in sulfur mustard-injured patients.

PubMed

Jafari, Mahvash; Ghanei, Mostafa

2010-03-01

Sulfur mustard (SM) is a strong alkylating agent that causes acute and chronic effects on different organs following exposure. Main late respiratory complications are chronic obstructive pulmonary disease, bronchiectasis, asthma, and bronchiolitis obliterans. It seems that oxidative stress plays a major role in pathogenesis of diseases. This study was undertaken to evaluate the long-term effect of SM on plasma, erythrocytes, and brochoalveolar lavage fluid antioxidant defense system in SM-injured patients. Brochoalveolar lavage fluid, plasma, and erythrocyte samples were taken from 54 patients in the case group exposed to SM and 25 controls with chronic respiratory disease without a history of exposure to SM. Superoxide dismutase, catalase, and glutathione peroxidase activities in lavage fluid, plasma, and erythrocytes were significantly higher in case group. The increased glutathione S-transferase activity in lavage fluid was associated with a depletion of glutathione and an increase of malondialdehyde levels. There was no significant change observed in glutathione reductase activity. The data suggest that oxidative damage might have an important role for patients exposed to SM. SM may induce an oxidative stress response by depleting the antioxidant defense systems and increasing lipid peroxidation in lung cells.

Hepatoprotective activity of Tribulus terrestris extract against acetaminophen-induced toxicity in a freshwater fish (Oreochromis mossambicus).

PubMed

Kavitha, P; Ramesh, R; Bupesh, G; Stalin, A; Subramanian, P

2011-12-01

The potential protective role of Tribulus terrestris in acetaminophen-induced hepatotoxicity in Oreochromis mossambicus was investigated. The effect of oral exposure of acetaminophen (500 mg/kg) in O. mossambicus at 24-h duration was evaluated. The plant extract (250 mg/kg) showed a remarkable hepatoprotective activity against acetaminophen-induced hepatotoxicity. It was judged from the tissue-damaging level and antioxidant levels in liver, gill, muscle and kidney tissues. Further acetaminophen impact induced a significant rise in the tissue-damaging level, and the antioxidant level was discernible from the enzyme activity modulations such as glutamate oxaloacetic transaminase, glutamate pyruvic transaminase, alkaline phosphatase, acid phosphatase, glucose-6-phosphate dehydrogenase, lactate dehydrogenase, superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, glutathione S-transferase, lipid peroxidase and reduced glutathione. The levels of all these enzymes have significantly (p < 0.05) increased in acetaminophen-treated fish tissues. The elevated levels of these enzymes were significantly controlled by the treatment of T. terrestris extract (250 kg/mg). Histopathological changes of liver, gill and muscle samples were compared with respective controls. The results of the present study specify the hepatoprotective and antioxidant properties of T. terrestris against acetaminophen-induced toxicity in freshwater fish, O. mossambicus.

Polyphenols of virgin coconut oil prevent pro-oxidant mediated cell death.

PubMed

Illam, Soorya Parathodi; Narayanankutty, Arunaksharan; Raghavamenon, Achuthan C

2017-07-01

Virgin coconut oil (VCO), extracted from the fresh coconut kernel, is a food supplement enriched with medium chain saturated fatty acids and polyphenolic antioxidants. It is reported to have several health benefits including lipid lowering, antioxidant and anti-inflammatory activities. The pharmacological benefits of VCO have been attributed to its polyphenol content (VCOP), the mechanistic basis of which is less explored. Liquid chromatography/mass spectroscopy (LC/MS) analysis of VCOP documented the presence of gallic acid, ferulic acid (FA), quercetin, methyl catechin, dihydrokaempferol and myricetin glycoside. Pre-treatment of VCOP at different concentrations (25-100 μg/mL) significantly reduced the H 2 O 2 and 2,2'-azobis (2-amidinopropane) dihydrochloride (AAPH) induced cell death in HCT-15 cells. Giving further insight to its mechanistic basis, oxidative stress induced alterations in glutathione (GSH) levels and activities of GR (Glutathione-Reductase), GPx (Glutathione-Peroxidase), GST (Glutathione-S-Transferase) and catalase (CAT) were restored to near-normal by VCOP, concomitantly reducing lipid peroxidation. The efficacy of VCOP was similar to that of Trolox and FA added in culture. The study thus suggests that VCOP protects cells from pro-oxidant insults by modulating cellular antioxidant status.

Protective role of Aloe vera against X-ray induced testicular dysfunction.

PubMed

Bala, S; Chugh, N A; Bansal, S C; Garg, M L; Koul, A

2017-09-01

The present investigation was carried out to evaluate the possible radioprotective potential of an Aloe vera extract against whole-body X-ray irradiation-induced testicular alterations in mice. Male balb/c mice were divided into four groups: control, A. vera, X-ray and A. vera pre-treated + X-ray irradiated. Histopathological examination revealed significant structural alterations in testes after X-ray exposure, which was also associated with the presence of apoptotic cells as assessed by TUNEL assay. X-ray irradiation resulted in elevation in the levels of reactive oxygen species, lipid peroxidation, a reduction in glutathione concentration and enhanced activities of antioxidant enzymes such as glutathione reductase, glutathione peroxidase, catalase, superoxide dismutase and glutathione-S-transferase. Sperm count/motility and testosterone levels were significantly decreased in the irradiated group. Irradiated animals pre-treated with A. vera extract revealed an improvement in antioxidant status, inhibition of lipid peroxides, apoptotic cell formation and enhanced testicular parameters when compared to the X-ray-exposed group. These findings suggest that A. vera extract could ameliorate X-ray-induced damage due to its free radical scavenging properties and its potential to boost cellular antioxidant defence machinery. © 2016 Blackwell Verlag GmbH.

The disturbance of antioxidant/oxidant balance in fish experimentally infected by Aeromonas caviae: Relationship with disease pathophysiology.

PubMed

Baldissera, Matheus D; Souza, Carine F; Parmeggiani, Belisa; Leipnitz, Guilhian; Verdi, Camila Marina; Santos, RobertoC V; Stefani, Lenita M; Baldisserotto, Bernardo

2018-06-07

Aeromonas caviae is a Gram-negative bacterium rarely found in fish but it can be associated to high mortality of infected animals. The disease pathogenesis in fish associated to liver and kidney lesions directly linked to the initiation and progression of the disease remains poorly understood. Thus, the aim of this study was to evaluate whether A. caviae infection causes oxidative stress in liver and kidney of silver catfish Rhamdia quelen, and its involvement in disease pathogenesis. Reactive oxygen species (ROS) and thiobarbituric acid reactive substances (TBARS) levels increased in liver and kidney of fish experimentally infected by A. caviae compared to the control uninfected group. On the other hand, non-protein sulfhydryl (NPSH) levels decreased in both tissues of infected animals, while the glutathione S-transferase (GST) activity decreased only in the hepatic tissue. No difference was observed between groups in both tissues regarding superoxide dismutase (SOD), glutathione peroxidase (GPx), glutathione reductase (GR) activities and glutathione (GSH) levels. In summary, the disturbance of hepatic and renal antioxidant/oxidant equilibrium contributes to the pathophysiology of the disease in fish experimentally infected by A. caviae. Copyright © 2018 Elsevier Ltd. All rights reserved.

Protective Effect of Zingiber officinale Against Dalton's Lymphoma Ascites Tumour by Regulating Inflammatory Mediator and Cytokines.

PubMed

Rubila, Sundararaj; Ranganathan, Thottiam Vasudevan; Sakthivel, Kunnathur Murugesan

2016-12-01

The aim of the present investigation was to evaluate Zingiber officinale paste against Dalton's lymphoma ascites (DLA)-induced tumours in Swiss albino mice. Experimental animals received Z. officinale paste (low dose 100 mg/kg bw and high dose 500 mg/kg bw) orally for eight alternative days. Treatment with Z. officinale paste showed significant increase in haemoglobin level and decrease in aspartate amino transferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP) and gamma glutamyl transferase (γ-GT) level. Z. officinale paste reduced the inflammatory mediators and cytokine levels, such as inducible nitric oxide (iNOS), tumour necrosis factor level (TNF-α) and interleukin-1β (IL-1β). Treatment with Z. officinale paste also significantly increased the antioxidant enzyme level, such as superoxide dismutase (SOD), catalase (CAT), reduced glutathione (GSH) and glutathione transferase (GST), and decreased the lipid peroxidation. Treatment also increased the vitamin C and E levels in treated animals compared with the DLA-bearing host. Histopathological studies also confirmed the protective influence of Z. officinale paste against DLA. The present study suggested that Z. officinale paste could be used as natural spice and a potent antitumour agent.

Neuroprotection by 6-(methylsulfinyl)hexyl isothiocyanate in a 6-hydroxydopamine mouse model of Parkinson׳s disease.

PubMed

Morroni, Fabiana; Sita, Giulia; Tarozzi, Andrea; Cantelli-Forti, Giorgio; Hrelia, Patrizia

2014-11-17

A number of pathogenic factors have been implicated in the progression of Parkinson׳s disease (PD), including oxidative stress, mitochondrial dysfunction, inflammation, excitotoxicity, and signals mediating apoptosis cascade. 6-(methylsulfinyl)hexyl isothiocyanate (6-MSITC) is a major component in wasabi, a very popular spice in Japan and a member of the Brassica family of vegetables. This study was designed to investigate the neuroprotective effects of 6-MSITC in a PD mouse model. Mice were treated with 6-MSITC (5mg/kg twice a week) for four weeks after the unilateral intrastriatal injection of 6-hydroxydopamine (6-OHDA). On the 28th day, 6-OHDA-injected mice showed behavioral impairments, a significant decrease in tyrosine hydroxylase (TH) and an increase in apoptosis. In addition, lesioned mice showed reduced glutathione levels and glutathione-S-transferase and glutathione reductase activities. Notably, 6-MSITC demonstrated neuroprotective effects in our experimental model strongly related to the preservation of functional nigral dopaminergic neurons, which contributed to the reduction of motor dysfunction induced by 6-OHDA. Furthermore, this study provides evidence that the beneficial effects of 6-MSITC could be attributed to the decrease of apoptotic cell death and to the activation of glutathione-dependent antioxidant systems. These findings may render 6-MSITC as a promising molecule for further pharmacological studies on the investigation for disease-modifying treatment in PD. Copyright © 2014 Elsevier B.V. All rights reserved.

Understanding the main route of drug entry in adult Fasciola hepatica: Further insights into closantel pharmacological activity.

PubMed

Ceballos, L; Canton, C; Cadenazzi, G; Larsen, K; Virkel, G; Moreno, L; Fairweather, I; Lanusse, C; Alvarez, L

2017-10-01

Closantel (CLS) is highly effective against adult liver flukes after its oral or subcutaneous (sc) administration in ruminants. Trans-tegumental diffusion and oral ingestion are the two potential routes available for the entry of drugs into Fasciola hepatica. The work reported here contributes to improve the understanding of CLS pharmacology. The main goals of were: I) to determine the pattern of in vivo CLS accumulation into adult F. hepatica and relevant tissues in CLS-treated sheep; II) to investigate the influence of the physicochemical composition of the incubation medium on the CLS diffusion process into adult F. hepatica; III) to assess the ovicidal activity of CLS against F. hepatica eggs; and IV) to investigate the in vivo effect of CLS treatment on glutathione S-transferases activity in adult liver flukes exposed to CLS. Fourteen healthy sheep were each orally infected with 75 F. hepatica metacercariae. Sixteen (16) weeks after infection, animals were treated with CLS by oral (n = 6, 10 mg/kg) or sub-cutaneous (sc) (n = 6, 5 mg/kg) route. At 12, 24 and 36 h post-treatment, animals were sacrificed (n = 2) and samples of blood, bile and adult F. hepatica were collected. In addition, flukes recovered from non-treated sheep (n = 2) were ex vivo incubated (60 min) in the presence of CLS in either RPMI or bile as incubation medium. CLS concentration was measured by HPLC. The ovicidal activity of CLS was investigated using eggs obtained from the bile of untreated sheep. Finally, glutathione S-transferase activity in F. hepatica recovered from untreated and CLS-treated sheep was assessed. In the in vivo studies, the highest CLS concentrations were measured in plasma and adult liver flukes. A positive correlation was observed between CLS concentration in plasma and in F. hepatica. Results obtained in the current work indicate that the in vivo accumulation of CLS into adult liver flukes occurs mainly by the oral route. After ex vivo incubation, the uptake of CLS by the parasite was markedly diminished in the presence of bile compared with that observed in the presence of RPMI as incubation medium. CLS lacks ovicidal activity at therapeutically relevant concentrations. Lastly, CLS significantly increased glutathione S-transferase activity in flukes recovered at 12 h (oral treatment) and 24 h (sc treatment), compared to the control liver flukes. Copyright © 2017 Elsevier Inc. All rights reserved.

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

Glutathione S Transferases Polymorphisms Are Independent Prognostic Factors in Lupus Nephritis Treated with Cyclophosphamide

PubMed Central

Verstuyft, Céline; Costedoat-Chalumeau, Nathalie; Hummel, Aurélie; Le Guern, Véronique; Sacré, Karim; Meyer, Olivier; Daugas, Eric; Goujard, Cécile; Sultan, Audrey; Lobbedez, Thierry; Galicier, Lionel; Pourrat, Jacques; Le Hello, Claire; Godin, Michel; Morello, Rémy; Lambert, Marc; Hachulla, Eric; Vanhille, Philippe; Queffeulou, Guillaume; Potier, Jacky; Dion, Jean-Jacques; Bataille, Pierre; Chauveau, Dominique; Moulis, Guillaume; Farge-Bancel, Dominique; Duhaut, Pierre; Saint-Marcoux, Bernadette; Deroux, Alban; Manuzak, Jennifer; Francès, Camille; Aumaitre, Olivier; Bezanahary, Holy; Becquemont, Laurent; Bienvenu, Boris

2016-01-01

Objective To investigate association between genetic polymorphisms of GST, CYP and renal outcome or occurrence of adverse drug reactions (ADRs) in lupus nephritis (LN) treated with cyclophosphamide (CYC). CYC, as a pro-drug, requires bioactivation through multiple hepatic cytochrome P450s and glutathione S transferases (GST). Methods We carried out a multicentric retrospective study including 70 patients with proliferative LN treated with CYC. Patients were genotyped for polymorphisms of the CYP2B6, CYP2C19, GSTP1, GSTM1 and GSTT1 genes. Complete remission (CR) was defined as proteinuria ≤0.33g/day and serum creatinine ≤124 µmol/l. Partial remission (PR) was defined as proteinuria ≤1.5g/day with a 50% decrease of the baseline proteinuria value and serum creatinine no greater than 25% above baseline. Results Most patients were women (84%) and 77% were Caucasian. The mean age at LN diagnosis was 41 ± 10 years. The frequency of patients carrying the GST null genotype GSTT1-, GSTM1-, and the Ile→105Val GSTP1 genotype were respectively 38%, 60% and 44%. In multivariate analysis, the Ile→105Val GSTP1 genotype was an independent factor of poor renal outcome (achievement of CR or PR) (OR = 5.01 95% CI [1.02–24.51]) and the sole factor that influenced occurrence of ADRs was the GSTM1 null genotype (OR = 3.34 95% CI [1.064–10.58]). No association between polymorphisms of cytochrome P450s gene and efficacy or ADRs was observed. Conclusion This study suggests that GST polymorphisms highly impact renal outcome and occurrence of ADRs related to CYC in LN patients. PMID:27002825

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.

Sugar-binding sites of the HA1 subcomponent of Clostridium botulinum type C progenitor toxin.

PubMed

Nakamura, Toshio; Tonozuka, Takashi; Ide, Azusa; Yuzawa, Takayuki; Oguma, Keiji; Nishikawa, Atsushi

2008-02-22

Clostridium botulinum type C 16S progenitor toxin contains a hemagglutinin (HA) subcomponent, designated HA1, which appears to play an important role in the effective internalization of the toxin in gastrointestinal epithelial cells and in creating a broad specificity for the oligosaccharide structure that corresponds to various targets. In this study, using the recombinant protein fused to glutathione S-transferase, we investigated the binding specificity of the HA1 subcomponent to sugars and estimated the binding sites of HA1 based on X-ray crystallography and soaking experiments using various sugars. N-Acetylneuraminic acid, N-acetylgalactosamine, and galactose effectively inhibited the binding that occurs between glutathione S-transferase-HA1 and mucins, whereas N-acetylglucosamine and glucose did not inhibit it. The crystal structures of HA1 complex with N-acetylneuraminic acid, N-acetylgalactosamine, and galactose were also determined. There are two sugar-binding sites, sites I and II. Site I corresponds to the electron densities noted for all sugars and is located at the C-terminal beta-trefoil domain, while site II corresponds to the electron densities noted only for galactose. An aromatic amino acid residue, Trp176, at site I has a stacking interaction with the hexose ring of the sugars. On the other hand, there is no aromatic residue at site II; thus, the interaction with galactose seems to be poor. The double mutant W176A at site I and D271F at site II has no avidity for N-acetylneuraminic acid but has avidity for galactose. In this report, the binding specificity of botulinum C16S toxin HA1 to various sugars is demonstrated based on its structural features.

Ameliorative effect of propolis supplementation on alleviating bisphenol-A toxicity: Growth performance, biochemical variables, and oxidative stress biomarkers of Nile tilapia, Oreochromis niloticus (L.) fingerlings.

PubMed

Hamed, Heba S; Abdel-Tawwab, Mohsen

2017-11-01

Bisphenol-A (BPA) is one of the important pollutants in aquatic ecosystems and its detrimental effect on fish has a great concern. Propolis is a natural immune-stimulant that has various biological and pharmacological activities. Thus, its capability to alleviate the toxic effect of BPA on Nile tilapia, Oreochromis niloticus (L.) performance was assessed in a study based on a 2×2 factorial design with two levels of ethanolic extract of propolis (EEP) and two waterborne BPA concentrations in triplicates. Fish (33.9±0.55g) were exposed to 0.0 or 1.64μgBPA/L for 6weeks during which fish were fed on diets containing 0.0 or 9.0gEEP/kg diet. Fish performance, biochemical variables, and oxidative stress enzymes were significantly affected by propolis supplementation, BPA exposure, and their interaction. Propolis supplementation significantly improved fish growth and feed intake, which were significantly retarded by BPA exposure. Additionally, total protein, albumin, globulin, and acetylcholine esterase (AChE) decreased significantly. Meanwhile aspartate transferase (AST), alanine transferase (ALT), alkaline phosphatase (ALP), creatinine, and uric acid increased significantly with exposure to BPA. Levels of malondialdehyde (MDA) as well as superoxide dismutase (SOD) and catalase (CAT) activities increased significantly due to BPA exposure, whereas significant reductions in the activity of glutathione peroxidase (GPx) and glutathione S-transferase (GST) were also recorded compared to the control fish. It is noticed that EEP co-administration ameliorated these parameters. The present results evoked that propolis administration improves fish growth and alleviated BPA-induced toxicity. Copyright © 2017 Elsevier Inc. All rights reserved.

Effect of boric acid on antioxidant enzyme activity, lipid peroxidation, and ultrastructure of midgut and fat body of Galleria mellonella.

PubMed

Büyükgüzel, Ender; Büyükgüzel, Kemal; Snela, Milena; Erdem, Meltem; Radtke, Katarzyna; Ziemnicki, Kazimierz; Adamski, Zbigniew

2013-04-01

Boric acid is widely used as an insecticide, acaricide, herbicide, and fungicide and also during various industrial processings. Hence, numerous populations are subjects to this toxic compound. Its action on animals is still not fully known and understood. We examined the effect of boric acid on larvae of greater wax moth (Galleria mellonella). The chemical appeared to be toxic for larvae, usually in a concentration-dependent manner. Exposed groups revealed increased lipid peroxidation and altered activity of catalase, superoxide dismutase, glutathione S-transferase, and glutathione peroxidase. We also observed changes of ultrastructure, which were in tune with biochemical assays. We suggest that boric acid has a broad mode of action, which may affect exposed larvae, and even if sublethal, they may lead to disturbances within exposed populations.

Surviving in a toxic world: transcriptomics and gene expression profiling in response to environmental pollution in the critically endangered European eel

PubMed Central

2012-01-01

Background Genomic and transcriptomic approaches have the potential for unveiling the genome-wide response to environmental perturbations. The abundance of the catadromous European eel (Anguilla anguilla) stock has been declining since the 1980s probably due to a combination of anthropogenic and climatic factors. In this paper, we explore the transcriptomic dynamics between individuals from high (river Tiber, Italy) and low pollution (lake Bolsena, Italy) environments, which were measured for 36 PCBs, several organochlorine pesticides and brominated flame retardants and nine metals. Results To this end, we first (i) updated the European eel transcriptome using deep sequencing data with a total of 640,040 reads assembled into 44,896 contigs (Eeelbase release 2.0), and (ii) developed a transcriptomic platform for global gene expression profiling in the critically endangered European eel of about 15,000 annotated contigs, which was applied to detect differentially expressed genes between polluted sites. Several detoxification genes related to metabolism of pollutants were upregulated in the highly polluted site, including genes that take part in phase I of the xenobiotic metabolism (CYP3A), phase II (glutathione-S-transferase) and oxidative stress (glutathione peroxidase). In addition, key genes in the mitochondrial respiratory chain and oxidative phosphorylation were down-regulated at the Tiber site relative to the Bolsena site. Conclusions Together with the induced high expression of detoxification genes, the suggested lowered expression of genes supposedly involved in metabolism suggests that pollution may also be associated with decreased respiratory and energy production. PMID:23009661

[The activity of glutathione antioxidant system at melaksen and valdoxan action under experimental hyperthyroidism in rats].

PubMed

Gorbenko, M V; Popova, T N; Shul'gin, K K; Popov, S S

2013-01-01

Investigation of glutathione antioxidant system activity and diene conjugates content in rats liver and blood serum at the influence of melaksen and valdoxan under experimental hyperthyroidism (EG) has been revealed. It has been established that the activities of glutathione reductase (GR), glutathione peroxidase (GP) and glutathione transferase (GT), growing at pathological conditions, change to the side of control value at these substunces introduction. Reduced glutathione content (GSH) at melaxen and valdoxan action increased compared with values under the pathology, that, obviously, could be associated with a reduction of its spending on the detoxication of free radical oxidation (FRO) toxic products. Diene conjugates level in rats liver and blood serum, increasing at experimental hyperthyroidism conditions, under introduction of melatonin level correcting drugs, also approached to the control meaning. Results of the study indicate on positive effect of melaxen and valdoxan on free radical homeostasis, that appears to be accompanied by decrease of load on the glutathione antioxidant system in comparison with the pathology.

Vicissitudes of oxidative stress biomarkers in the estuarine crab Scylla serrata with reference to dry and wet weather conditions in Ennore estuary, Tamil Nadu, India.

PubMed

Ragunathan, M G

2017-03-15

The primary objective of this study was to understand the impact of monsoon and summer seasons on the Polychlorinated Biphenyls (PCB's) and petroleum hydrocarbon compounds (PHC's) load in Ennore estuary and how the physiological response of estuarine Scylla serrata inhabiting in this estuary changed with reference to antioxidant defense. Seasonal levels of PCB's and PHC's were assessed in the water along with their bioaccumulation in gills, hemolymph, hepatopancreas and ovary of S. serrata. Concentration of PCB's and PHC's in water and their bioaccumulation was found to be higher in summer season when compared to monsoon season. Enzymic antioxidant assays [superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX), glutathione reductase (GR), glutathione-S-transferase (GST)]; non-enzymic antioxidant assays [glutathione (GSH), vitamin C, vitamin E] and macromolecular alterations [membrane lipid peroxidation (LPO), and DNA Damage (strand breaks)] were assessed in the gills, hemolymph and hepatopancreas of S. serrata. There was a significant (p<0.05) upregulation in lipid peroxidation activity and DNA damage activity collected during the summer season when compared to the pre- and post-monsoon seasons. On the contrary, the enzymic and non-enzymic antioxidants exhibited significant (p<0.05) down regulation in the gills, hemolymph, hepatopancreas and ovary of S. serrata. Oxidative stress biomarkers represented a significant (p<0.05) maximum in gills when compared to hemolymph and hepatopancreas of S. serrata. Present study provided scientific evidences of how the antioxidant defense status of S. serrata responded to PCB's and PAH's stress with reference to seasonal vicissitudes, which indirectly represented the environmental health conditions of the estuary. Copyright © 2017 Elsevier Ltd. All rights reserved.

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 through S-glutathionylation of a series of key interrelated proteins. Antioxid. Redox Signal. 26, 247–261. PMID:26838680

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.

Structural and Biochemical Analyses Reveal the Mechanism of Glutathione S-Transferase Pi 1 Inhibition by the Anti-cancer Compound Piperlongumine.

PubMed

Harshbarger, Wayne; Gondi, Sudershan; Ficarro, Scott B; Hunter, John; Udayakumar, Durga; Gurbani, Deepak; Singer, William D; Liu, Yan; Li, Lianbo; Marto, Jarrod A; Westover, Kenneth D

2017-01-06

Glutathione S-transferase pi 1 (GSTP1) is frequently overexpressed in cancerous tumors and is a putative target of the plant compound piperlongumine (PL), which contains two reactive olefins and inhibits proliferation in cancer cells but not normal cells. PL exposure of cancer cells results in increased reactive oxygen species and decreased GSH. These data in tandem with other information led to the conclusion that PL inhibits GSTP1, which forms covalent bonds between GSH and various electrophilic compounds, through covalent adduct formation at the C7-C8 olefin of PL, whereas the C2-C3 olefin of PL was postulated to react with GSH. However, direct evidence for this mechanism has been lacking. To investigate, we solved the X-ray crystal structure of GSTP1 bound to PL and GSH at 1.1 Å resolution to rationalize previously reported structure activity relationship studies. Surprisingly, the structure showed that a hydrolysis product of PL (hPL) was conjugated to glutathione at the C7-C8 olefin, and this complex was bound to the active site of GSTP1; no covalent bond formation between hPL and GSTP1 was observed. Mass spectrometry (MS) analysis of the reactions between PL and GSTP1 confirmed that PL does not label GSTP1. Moreover, MS data also indicated that nucleophilic attack on PL at the C2-C3 olefin led to PL hydrolysis. Although hPL inhibits GSTP1 enzymatic activity in vitro, treatment of cells susceptible to PL with hPL did not have significant anti-proliferative effects, suggesting that hPL is not membrane-permeable. Altogether, our data suggest a model wherein PL is a prodrug whose intracellular hydrolysis initiates the formation of the hPL-GSH conjugate, which blocks the active site of and inhibits GSTP1 and thereby cancer cell proliferation. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

Aberrant Epigenetic Alterations of Glutathione-S-Transferase P1 in Age-Related Nuclear Cataract.

PubMed

Chen, Jia; Zhou, Jing; Wu, Jian; Zhang, Guowei; Kang, Lihua; Ben, Jindong; Wang, Yong; Qin, Bai; Guan, Huaijin

2017-03-01

Oxidative damage of lens tissue contributes to the formation of age-related cataract. Pi-class glutathione-S-transferase (GSTP1) plays a role in the removal of oxidative adducts by transferring them to glutathione. To assess epigenetic regulation of GSTP1 and its potential role in age-related nuclear cataract (ARNC) pathogenesis, we evaluated GSTP1 mRNA expression, methylation, and chromatin modifications in lenses from ARNC patients. The mRNA and protein of lens GSTP1 were assayed by relative quantitative real-time polymerase chain reaction (qRT-PCR) and Western blots. Methylation of the GSTP1 promoter was determined by bisulfite genomic sequencing. Chromatin modification was detected by chromatin immunoprecipitation. DNA methyltransferase (DNMT) and histone deacetylase (HDAC) activities were also assayed by enzyme-linked immunosorbent assay (ELISA)-like reaction. To assess the effect of DNA methylation on the mRNA expression of GSTP1, human lens epithelium HLE-B3 cells were treated with the demethylation compound 5-aza-dC, followed by qRT-PCR assay. GSTP1 mRNA and protein levels were significantly reduced in lens epithelium and cortex of ARNC cases versus age-matched controls. The changes corresponded to hypermethylation of the GSTP1 promoter CpG islands. The loss of GSTP1 mRNA and protein and the increased DNA promoter methylation might be correlated with the severity of the ARNC. ARNC lenses also had lower acetylation of histone proteins H3, H4, and lower methylation of H3K4, and higher methylation of H3K9. Histone modifications were not correlated with the severity of the ARNCs. DNMT and HDAC were elevated in lenses from ARNCs compared with controls. Demethylation treatment of HLE-B3 cells with 5-aza-dC enhanced the expression of GSTP1. Epigenetic alteration of GSTP1 regulates its expression in lens epithelial and cortical tissues. These changes likely contribute to the pathogenesis of ARNC.

Structural and Biochemical Analyses Reveal the Mechanism of Glutathione S-Transferase Pi 1 Inhibition by the Anti-cancer Compound Piperlongumine*

PubMed Central

Harshbarger, Wayne; Gondi, Sudershan; Ficarro, Scott B.; Hunter, John; Udayakumar, Durga; Gurbani, Deepak; Singer, William D.; Liu, Yan; Li, Lianbo; Marto, Jarrod A.; Westover, Kenneth D.

2017-01-01

Glutathione S-transferase pi 1 (GSTP1) is frequently overexpressed in cancerous tumors and is a putative target of the plant compound piperlongumine (PL), which contains two reactive olefins and inhibits proliferation in cancer cells but not normal cells. PL exposure of cancer cells results in increased reactive oxygen species and decreased GSH. These data in tandem with other information led to the conclusion that PL inhibits GSTP1, which forms covalent bonds between GSH and various electrophilic compounds, through covalent adduct formation at the C7-C8 olefin of PL, whereas the C2-C3 olefin of PL was postulated to react with GSH. However, direct evidence for this mechanism has been lacking. To investigate, we solved the X-ray crystal structure of GSTP1 bound to PL and GSH at 1.1 Å resolution to rationalize previously reported structure activity relationship studies. Surprisingly, the structure showed that a hydrolysis product of PL (hPL) was conjugated to glutathione at the C7-C8 olefin, and this complex was bound to the active site of GSTP1; no covalent bond formation between hPL and GSTP1 was observed. Mass spectrometry (MS) analysis of the reactions between PL and GSTP1 confirmed that PL does not label GSTP1. Moreover, MS data also indicated that nucleophilic attack on PL at the C2-C3 olefin led to PL hydrolysis. Although hPL inhibits GSTP1 enzymatic activity in vitro, treatment of cells susceptible to PL with hPL did not have significant anti-proliferative effects, suggesting that hPL is not membrane-permeable. Altogether, our data suggest a model wherein PL is a prodrug whose intracellular hydrolysis initiates the formation of the hPL-GSH conjugate, which blocks the active site of and inhibits GSTP1 and thereby cancer cell proliferation. PMID:27872191