The Effects of Lycopene on the Methylation of the GSTP1 Promoter and Global Methylation in Prostatic Cancer Cell Lines PC3 and LNCaP

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Li-Juan Fu

2014-01-01

Full Text Available DNA (cytosine-5- methylation silencing of GSTP1 function occurs in prostate adenocarcinoma (PCa. Previous studies have shown that there is an inverse relationship between dietary lycopene intake and the risk of PCa. However, it is unknown whether lycopene reactivates the tumor suppressor gene glutathioneS-transferase-π (GSTP1 by demethylation of the hypermethylated CpGs that act to silence the GSTP1 promoter. Here, we demonstrated that lycopene treatment significantly decreased the methylation levels of the GSTP1 promoter and increased the mRNA and protein levels of GSTP1 in an androgen-independent PC-3 cell line. In contrast, lycopene treatment did not demethylate the GSTP1 promoter or increase GSTP1 expression in the androgen-dependent LNCaP cell line. DNA methyltransferase (DNMT 3A protein levels were downregulated in PC-3 cells following lycopene treatment; however, DNMT1 and DNMT3B levels were unchanged. Furthermore, the long interspersed element (LINE-1 and short interspersed element ALU were not demethylated when treated by lycopene. In LNCaP cells, lycopene treatment did not affect any detected DNMT protein expression, and the methylation levels of LINE-1 and ALU were decreased. These results indicated that the protective effect of lycopene on the prostate is different between androgen-dependent and androgen-independent derived PCa cells. Further, in vivo studies should be conducted to confirm these promising results and to evaluate the potential role of lycopene in the protection of the prostate.

The dyad palindromic glutathione transferase P enhancer binds multiple factors including AP1.

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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 lac...

Predictive role of GSTP1-containing exosomes in chemotherapy-resistant breast cancer.

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Yang, Su-Jin; Wang, Dan-Dan; Li, Jian; Xu, Han-Zi; Shen, Hong-Yu; Chen, Xiu; Zhou, Si-Ying; Zhong, Shan-Liang; Zhao, Jian-Hua; Tang, Jin-Hai

2017-08-05

Anthracycline/taxane-based chemotherapy regimens are usually used as neoadjuvant chemotherapies to decrease tumour size and prevent metastasis of advanced breast cancer. However, patients have a high risk of developing chemo-resistance during treatment through still unknown mechanisms. Glutathione S-transferase P1 (GSTP1), which belongs to the family of phase II metabolic enzymes, has been reported to function in detoxifying several anti-cancer drugs by conjugating them with glutathione. Previous studies have identified GSTP1 as a predictor of prognosis and chemo-resistance in breast cancer patients, but the mechanisms governing GSTP1-dependent drug resistance are still unclear. We have found that GSTP1 expression is much higher in adriamycin-resistant cells and their corresponding exosomes. The role of GSTP1-containing exosomes in conferring drug resistance was analysed through cell apoptosis and immunofluorescence staining assays. Furthermore, we analysed 42 cases of paired breast cancer tissues collected before and after anthracycline/taxane-based neoadjuvant chemotherapy by immunohistochemistry. Higher GSTP1 expression was shown in the progressive disease (PD)/stable disease (SD) group than in the partial response (PR)/complete response (CR) group both in the samples collected before and after the chemotherapy treatment. Interestingly, GSTP1 partly re-localized from the cell nucleus to the cytoplasm upon treatment, and similar results were obtained for the exosomal marker Tumour susceptibility gene 101 protein (TSG101), which also increased in the cytoplasm after chemotherapy. After analysing the serum exosomes of 30 patients treated with anthracycline/taxane-based neoadjuvant chemotherapy, we discovered that the levels of GSTP1 in exosomes from patients in the PD/SD group were significantly higher than those in the PR/CR group. Here, for the first time, we investigated a novel role for GSTP1-containing exosomes and their capability to transfer drug resistance

Regulation of epigenetic traits of the glutathione S-transferase P1 gene:From detoxification towards cancer prevention and diagnosis

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Marc eDiederich

2014-07-01

Full Text Available Glutathione S-transferases (GSTs are phase II drug detoxifying enzymes that play an essential role in maintenance of cell integrity and protection against DNA damage by catalyzing the conjugation of glutathione to a wide variety of exo- and endogenous electrophilic substrates. GSTP1, the gene encoding the pi­class GST is frequently inactivated by acquired somatic CpG island promoter hypermethylation in multiple cancer subtypes including prostate, breast, liver and blood cancers. Epigenetically mediated GSTP1 silencing is associated with enhanced cancer susceptibility by decreasing its caretaker gene function, which tends to promote neoplastic transformation allowing the cell to acquire additional alterations. Thus, this epigenetic alteration is now considered as a cancer biomarker but could as well play a driving role in multistep cancer development especially well documented in prostate cancer development.The present review discusses application of epigenetic alterations affecting GSTP1 in cancer medicine used alone or in combination with other biomarkers for cancer detection and diagnosis as well as for future targeted preventive and therapeutic interventions including by dietary agents.

Glutathione S-transferase P1, gene-gene interaction, and lung cancer susceptibility in the Chinese population: An updated meta-analysis and review

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Xue-Ming Li

2015-01-01

Full Text Available Aim of Study: To assess the impact of glutathione S-transferase P1 (GSTP1 Ile105Val polymorphism on the risk of lung cancer in the Chinese population, an updated meta-analysis and review was performed. Materials and Methods: Relevant studies were identified from PubMed, Springer Link, Ovid, Chinese Wanfang Data Knowledge Service Platform, Chinese National Knowledge Infrastructure, and Chinese Biology Medicine published through January 22, 2015. The odds ratios (ORs and 95% confidence intervals (CIs were calculated to estimate the strength of the associations. Results: A total of 13 case-control studies, including 2026 lung cancer cases and 2451 controls, were included in this meta-analysis. Overall, significantly increased lung cancer risk was associated with the variant genotypes of GSTP1 polymorphism in the Chinese population (GG vs. AA: OR = 1.36, 95% CI = 1.01-1.84. In subgroup analyses stratified by geographic area and source of controls, the significant results were found in population-based studies (GG vs. AA: OR = 1.62, 95% CI: 1.13-2.31; GG vs. AG: OR = 1.49, 95% CI: 1.03-2.16; GG vs. AA + AG: OR = 1.55, 95% CI: 1.12-2.26. A gene-gene interaction analysis showed that there was an interaction for individuals with combination of GSTM1 (or GSTT1 null genotype and GSTP1 (AG + GG mutant genotype for lung cancer risk in Chinese. Conclusion: This meta-analysis suggests that GSTP1 Ile105Val polymorphism may increase the risk of lung cancer in the Chinese population.

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.

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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.

The effect of chemical carcinogenesis on rat glutathione S-transferase P1 gene transcriptional regulation.

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Liu, D; Liao, M; Zuo, J; Henner, W D; Fan, F

2001-03-01

To investigate mechanisms of rat glutathione S-transferase P1 gene (rGSTP1) expression regulation during chemical carcinogenesis. we studied enhancer elements located in the region between -2.5 kb to -2.2 kb. The region was upstream from the start site of transcription and was divided into two major fragments, GPEI and GPEII. The GPEII fragment was further divided into two smaller fragments, GPEII- I and GPEII-2. Using a luciferase reporter system, we identified a strong enhancer of GPEI and a weak enhancer of GPEII in HeLa and a rat hepatoma cell line CBRH79 19 cell. The enhancer of GPEII was located within the GPEII-I region. Chemical stimulation by glycidyl methatylate (GMA) and phorbol 12-o-tetradecanoate 13-acetate (TPA) analysis revealed that induction of rGSTP1 expression was mainly through GPEI. Although H2O2 could enhance GPEII enhancer activity, the enhancement is not mediated by the NF-kappaB factor that bound the NF-kappaB site in GPEII. Using electrophoretic mobility shift assays (EMSA) and the UV cross-linking assays, we found that HeLa and CBRH7919 cells had proteins that specifically bound GPEI core sequence and a 64 kDa protein that interacted with GPEII-1. The cells from normal rat liver did not express the binding proteins. Therefore, the trans-acting factors seem to be closely related to GPEI, GPEII enhancer activities and may play an important role in high expression of rGSTPI gene.

Epidermal growth factor regulation of glutathione S-transferase gene expression in the rat is mediated by class Pi glutathione S-transferase enhancer I.

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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 no...

Glutathione S-transferase P influences redox and migration pathways in bone marrow.

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Jie Zhang

Full Text Available To interrogate why redox homeostasis and glutathione S-transferase P (GSTP are important in regulating bone marrow cell proliferation and migration, we isolated crude bone marrow, lineage negative and bone marrow derived-dendritic cells (BMDDCs from both wild type (WT and knockout (Gstp1/p2(-/- mice. Comparison of the two strains showed distinct thiol expression patterns. WT had higher baseline and reactive oxygen species-induced levels of S-glutathionylated proteins, some of which (sarco-endoplasmic reticulum Ca2(+-ATPase regulate Ca(2+ fluxes and subsequently influence proliferation and migration. Redox status is also a crucial determinant in the regulation of the chemokine system. CXCL12 chemotactic response was stronger in WT cells, with commensurate alterations in plasma membrane polarization/permeability and intracellular calcium fluxes; activities of the downstream kinases, ERK and Akt were also higher in WT. In addition, expression levels of the chemokine receptor CXCR4 and its associated phosphatase, SHP-2, were higher in WT. Inhibition of CXCR4 or SHP2 decreased the extent of CXCL12-induced migration in WT BMDDCs. The differential surface densities of CXCR4, SHP-2 and inositol trisphosphate receptor in WT and Gstp1/p2(-/- cells correlated with the differential CXCR4 functional activities, as measured by the extent of chemokine-induced directional migration and differences in intracellular signaling. These observed differences contribute to our understanding of how genetic ablation of GSTP causes different levels of myeloproliferation and migration [corrected

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.

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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.

GSTP1 Loss results in accumulation of oxidative DNA base damage and promotes prostate cancer cell survival following exposure to protracted oxidative stress.

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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

2016-02-01

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). 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. 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. 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. © 2015

Glutathione S-transferase gene polymorphisms in presbycusis.

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Ateş, Nurcan Aras; Unal, Murat; Tamer, Lülüfer; Derici, Ebru; Karakaş, Sevim; Ercan, Bahadir; Pata, Yavuz Selim; Akbaş, Yücel; Vayisoğlu, Yusuf; Camdeviren, Handan

2005-05-01

Glutathione and glutathione-related antioxidant enzymes are involved in the metabolism and detoxification of cytotoxic and carcinogenic compounds as well as reactive oxygen species. Reactive oxygen species generation occurs in prolonged relative hypoperfusion conditions such as in aging. The etiology of presbycusis is much less certain; however, a complex genetic cause is most likely. The effect of aging shows a wide interindividual range; we aimed to investigate whether profiles of (glutathione S-transferase (GST) M1, T1 and P1 genotypes may be associated with the risk of age-related hearing loss. We examined 68 adults with presbycusis and 69 healthy controls. DNA was extracted from whole blood, and the GSTM1, GSTT1 and GSTP1 polymorphisms were determined using a real-time polymerase chain reaction and fluorescence resonance energy transfer with a Light-Cycler Instrument. Associations between specific genotypes and the development of presbycusis were examined by use of logistic regression analyses to calculate odds ratios and 95% confidence intervals. Gene polymorphisms at GSTM1, GSTT1, and GSTP1 in subjects with presbycusis were not significantly different than in the controls (p > 0.05). Also, the combinations of different GSTM1, GSTT1, and GSTP1 genotypes were not an increased risk of presbycusis (p > 0.05). We could not demonstrate any significant association between the GSTM1, GSTT1, and GSTP1 polymorphism and age-related hearing loss in this population. This may be because of our sample size, and further studies need to investigate the exact role of GST gene polymorphisms in the etiopathogenesis of the presbycusis.

The dyad palindromic glutathione transferase P enhancer binds multiple factors including AP1.

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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.

Epidermal growth factor regulation of glutathione S-transferase gene expression in the rat is mediated by class Pi glutathione S-transferase enhancer I.

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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.

Glutathione S-transferase M1 and P1 polymorphisms and risk of breast cancer and fibrocystic breast conditions in Chinese women.

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Sakoda, Lori C; Blackston, Christie R; Xue, Kan; Doherty, Jennifer A; Ray, Roberta M; Lin, Ming Gang; Stalsberg, Helge; Gao, Dao Li; Feng, Ziding; Thomas, David B; Chen, Chu

2008-05-01

Enzymes encoded by the glutathione S-tranferase mu 1 (GSTM1) and pi 1 (GSTP1) genes, which are expressed in breast tissue, catalyze the detoxification of endogenous and exogenous electrophiles. Reduced enzyme activity, due to carriage of the GSTM1 deletion or the GSTP1 Ile105Val Val allele, may therefore affect susceptibility to breast cancer and related conditions. In a case-control study of Chinese women, we examined whether these polymorphisms were associated with risk of breast cancer and fibrocystic breast conditions. Women diagnosed with breast cancer (n=615) or fibrocystic breast conditions (n=467) were compared to women without clinical breast disease (n=878). We also examined whether these associations differed by menopausal status or by presence of proliferation in the extra-tumoral epithelium among women with breast cancer and in lesions among women with fibrocystic conditions. No overall association of either GST polymorphism with risk of breast cancer or fibrocystic breast conditions was observed. There was some evidence of slightly elevated cancer risk associated with carriage of the GSTM1 null genotype and at least one GSTP1 105-Val allele (OR=1.33, 95% CI, 0.99-1.80), compared to carriage of the GSTM1 non-null and GSTP1 Ile/Ile genotypes. This relationship was stronger in women who had breast cancer with extra-tumoral tissue proliferation (OR=1.77, 95% CI, 1.03-3.04). Our results suggest that GSTM1 and GSTP1 genotypes do not individually influence susceptibility to breast cancer or fibrocystic breast conditions. The observed increased risk of breast cancer associated with joint carriage of the GSTM1 null genotype and GSTP1 105-Val allele needs confirmation in other studies.

Does occupational exposure to solvents and pesticides in association with glutathione S-transferase A1, M1, P1, and T1 polymorphisms increase the risk of bladder cancer? The Belgrade case-control study.

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Marija G Matic

Full Text Available OBJECTIVE: We investigated the role of the glutathione S-transferase A1, M1, P1 and T1 gene polymorphisms and potential effect modification by occupational exposure to different chemicals in Serbian bladder cancer male patients. PATIENTS AND METHODS: A hospital-based case-control study of bladder cancer in men comprised 143 histologically confirmed cases and 114 age-matched male controls. Deletion polymorphism of glutathione S-transferase M1 and T1 was identified by polymerase chain reaction method. Single nucleotide polymorphism of glutathione S-transferase A1 and P1 was identified by restriction fragment length polymorphism method. As a measure of effect size, odds ratio (OR with corresponding 95% confidence interval (95%CI was calculated. RESULTS: The glutathione S-transferase A1, T1 and P1 genotypes did not contribute independently toward the risk of bladder cancer, while the glutathione S-transferase M1-null genotype was overrepresented among cases (OR = 2.1, 95% CI = 1.1-4.2, p = 0.032. The most pronounced effect regarding occupational exposure to solvents and glutathione S-transferase genotype on bladder cancer risk was observed for the low activity glutathione S-transferase A1 genotype (OR = 9.2, 95% CI = 2.4-34.7, p = 0.001. The glutathione S-transferase M1-null genotype also enhanced the risk of bladder cancer among subjects exposed to solvents (OR = 6,5, 95% CI = 2.1-19.7, p = 0.001. The risk of bladder cancer development was 5.3-fold elevated among glutathione S-transferase T1-active patients exposed to solvents in comparison with glutathione S-transferase T1-active unexposed patients (95% CI = 1.9-15.1, p = 0.002. Moreover, men with glutathione S-transferase T1-active genotype exposed to pesticides exhibited 4.5 times higher risk in comparison with unexposed glutathione S-transferase T1-active subjects (95% CI = 0.9-22.5, p = 0.067. CONCLUSION: Null or low-activity genotypes of the

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

OpenAIRE

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 acetyltransferas...

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

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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

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

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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.

GSTP1 A>G polymorphism and chemosensitivity of osteosarcoma: A meta-analysis

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Fengfeng Wu

2016-01-01

Full Text Available The association between GSTP1 A>G polymorphism and chemosensitivity of osteosarcoma is controversial according to previously published studies. We conducted this meta-analysis to further investigate the role of GSTP1 A>G genetic variation in response to chemotherapy resistance in patients with osteosarcoma. Using the electronic databases of Pubmed, Wanfang and CNIK were searched to find the studies related to the GSTP1 A>G polymorphism and chemosensitivity of osteosarcoma. The genotype of AA, AG and GG were extracted from the chemotherapy sensitivity and chemotherapy resistance group. The association between GSTP1 A>G polymorphism and chemosensitivity was calculated by STATA11.0 software. The correlation between GSTP1 A>G polymorphism and chemotherapy response was assessed by odds ratio (OR and its 95% confidence interval (95%CI. Four studies with 681 cases were finally included in this meta-analysis. The pooled data indicated that there was no significant association between GSTP1 A>G polymorphism and chemosensitivity in patients with osteosarcoma [Homozygous genetic model (GG vs AA: OR=0.53, 95%CI: 0.25-1.12, P=0.10; recessive genetic model (GG vs GA+AA: OR=0.61, 95%CI:0.34-1.11,P=0.11; and dominant genetic model (GG+AG vs AA: OR=0.67, 95%CI:0.42-1.07,P=0.10]. No correlation between GSTP1 A>G polymorphism and chemosensitivity was found according to this present meta-analysis. However, the small number of cases in each included study and significant statistical heterogeneity among the trials means the conclusion should be regarded as conservative.

Analysis of Polymorphisms in Genes (AGT, MTHFR, GPIIIa, and GSTP1 Associated with Hypertension, Thrombophilia and Oxidative Stress in Mestizo and Amerindian Populations of México

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Rocio Juárez-Velázquez

2010-01-01

Full Text Available 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.

The 341C/T polymorphism in the GSTP1 gene is associated with increased risk of oesophageal cancer

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Dandara Collet

2010-06-01

Full Text Available Abstract Background The Glutathione S-transferases (GSTs comprise a group of enzymes that are critical in the detoxification of carcinogens. In this study the effects of polymorphisms in these genes on the risk of developing oesophageal squamous cell carcinoma (OSCC were evaluated in a hospital-based case-control study in two South African population groups. Genetic polymorphisms in GSTs were investigated in 245 patients and 288 controls samples by PCR-RFLP analysis. Results The GSTP1 341T variant was associated with significantly increased risk of developing OSCC as observed from the odds ratios for the GSTP1 341C/T and GSTP1 341T/T genotypes (OR = 4.98; 95%CI 3.05-8.11 and OR = 10.9; 95%CI 2.43-49.1, respectively when compared to the homozygous GSTP1 341C/C genotype. The risk for OSCC in the combined GSTP1 341C/T and T/T genotypes was higher in tobacco smokers (OR = 7.51, 95% CI 3.82-14.7, alcohol consumers (OR = 15.3, 95% CI 1.81-12.9 and those using wood or charcoal for cooking and heating (OR = 12.1, 95% CI 3.26-49 when compared to those who did not smoke tobacco, or did not consume alcohol or user other forms of fuel for cooking and heating. Despite the close proximity of the two GSTP1 SNPs (313A>G and 341C>T, they were not in linkage disequilibrium in these two population groups (D':1.0, LOD: 0.52, r2: 0.225. The GSTP1 313A/G polymorphism on the other hand, did not display any association with OSSC. The homozygous GSTT1*0 genotype was associated with increased risk of OSCC (OR = 1.71, 95%CI 1.18-2.46 while the homozygous GSTM1*0 genotype was associated with significantly decreased risk of OSCC in the Mixed Ancestry subjects (OR= 0.39, 95%CI 0.25-0.62. Conclusions This study shows that the risk of developing OSCC in the South African population can be partly explained by genetic polymorphisms in GST coding genes and their interaction with environmental factors such as tobacco smoke and alcohol consumption.

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

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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.

Analysis of Polymorphisms in Genes (AGT, MTHFR, GPIIIa, and GSTP1) Associated with Hypertension, Thrombophilia and Oxidative Stress in Mestizo and Amerindian Populations of México

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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

Polymorphisms of glutathione-S-transferase M1, T1, P1 and the risk of prostate cancer: a case-control study

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Račay Peter

2009-03-01

Full Text Available Abstract Background It has been suggested that polymorphisms in glutathione-S-transferases (GST could predispose to prostate cancer through a heritable deficiency in detoxification pathways for environmental carcinogens. Yet, studies linking GST polymorphism and prostate cancer have so far failed to unambiguously establish this relation in patients. A retrospective study on healthy, unrelated subjects was conducted in order to estimate the population GST genotype frequencies in the Slovak population of men and compare our results with already published data (GSEC project-Genetic Susceptibility to Environmental Carcinogens. A further aim of the study was to evaluate polymorphisms in GST also in patients with prostate cancer in order to compare the evaluated proportions with those found in the control subjects. Methods We determined the GST genotypes in 228 healthy, unrelated subjects who attended regular prostate cancer screening between May 2005 and June 2007 and in 129 histologically verified prostate cancer patients. Analysis for the GST gene polymorphisms was performed by PCR and PCR-RFLP. Results We found that the GST frequencies are not significantly different from those estimated in a European multicentre study or from the results published by another group in Slovakia. Our results suggest that Val/Val genotype of GSTP1 gene could modulate the risk of prostate cancer, even if this association did not reach statistical significance. We did not observe significantly different crude rates of the GSTM1 and GSTT1 null genotypes in the men diagnosed with prostate cancer and those in the control group. Conclusion Understanding the contribution of GST gene polymorphisms and their interactions with other relevant factors may improve screening diagnostic assays for prostate cancer. We therefore discuss issues of study feasibility, study design, and statistical power, which should be taken into account in planning further trials.

Protective role for ovarian glutathione S-transferase isoform pi during 7,12-dimethylbenz[a]anthracene-induced ovotoxicity

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Bhattacharya, Poulomi, E-mail: poulomib@iastate.edu; Keating, Aileen F., E-mail: akeating@iastate.edu

2012-04-15

7,12-Dimethylbenz[a]anthracene (DMBA) destroys ovarian follicles at all developmental stages. This study investigated a role for the glutathione S-transferase (Gst) isoforms alpha (a), mu (m) and pi (p) and the transcription factors, Ahr and Nrf2, during DMBA-induced ovotoxicity, and their regulation by phosphatidylinositol-3 kinase (PI3K) signaling. Negative regulation of JNK by GSTP during DMBA exposure was also studied. Post-natal day (PND) 4 Fischer 344 rat ovaries were exposed to vehicle control (1% DMSO) ± DMBA (1 μM) or vehicle control (1% DMSO) ± LY294002 (PI3K inhibitor; 20 μM) for 1, 2, 4, or 6 days. Total RNA or protein was isolated, followed by RT-PCR or Western blotting to determine mRNA or protein level, respectively. Immunoprecipitation using an anti-GSTP antibody was performed to determine interaction between GSTP and JNK, followed by Western blotting to determine JNK and p-c-Jun protein level. DMBA had no impact on Gsta, Gstm or Nrf2 mRNA level, but increased Gstp mRNA and protein after 2 days. Ahr mRNA and protein increased after 2 and 4 days of DMBA exposure, respectively and DMBA increased NRF2 protein level after 4 days. JNK bound to GSTP was increased during DMBA exposure, with a concomitant decrease in unbound JNK and p-c-Jun. Ahr and Gstp mRNA were decreased (2 days) and increased (4 days) by PI3K inhibition, while Gstm mRNA increased (P < 0.05) after both time points, and there was no effect on Nrf2 mRNA. PI3K inhibition increased AHR, NRF2 and GSTP protein level. These findings support involvement of ovarian GSTP during DMBA exposure, and indicate a regulatory role for the PI3K signaling pathway on ovarian xenobiotic metabolism gene expression. -- Highlights: ► Ovarian GSTP is activated in response to DMBA exposure. ► AhR and Nrf2 transcription factors are up-regulated by DMBA. ► PI3K signaling regulates Ahr, Nrf2 and Gstp expression. ► GSTP negatively regulates ovarian JNK in response to DMBA exposure.

Effect of GSTM1, GSTT1, and GSTP1 IIe105Val polymorphisms on susceptiblity to gestational diabetes mellitus.

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Qiu, Y H; Xu, Y L; Zhang, W H

2016-06-03

We investigate the role of the GSTM1, GSTT1, and GSTP1 IIe105Val genetic polymorphisms in the susceptibility to gestational diabetes mellitus. A total of 223 pregnant women with gestational diabetes mellitus and 265 healthy pregnant women were examined at The Second Affiliated Hospital of Shaanxi University of Chinese Medicine from May 2013 to November 2013. Genotyping for detection of GSTM1, GSTT1, and GSTP1 IIe105Val polymorphisms was conducted using the restriction fragment length polymorphism-polymerase chain reaction. There were statistically significant differences between patients with gestational diabetes mellitus and control subjects in terms of age (χ(2) = 6.68, P = 0.01) and BMI (t = 7.56, P gestational diabetes mellitus compared to the present genotype [adjusted OR (95%CI) = 1.85 (1.26-2.72)]. However, the unconditional logistic analysis revealed that GSTT1 and GSTP1 IIe105Val polymorphisms could not influence the risk of gestational diabetes mellitus in a Chinese population. In summary, we suggest that the GSTM1 gene polymorphism could influence the susceptibility to gestational diabetes mellitus in a Chinese population.

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

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Alexandra Audemard-Verger

Full Text Available 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.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.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.This study suggests that GST polymorphisms highly impact renal outcome and occurrence of ADRs related to CYC in LN patients.

Glutathione S-transferase T1, O1 and O2 polymorphisms are associated with survival in muscle invasive bladder cancer patients.

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Tatjana I Djukic

Full Text Available OBJECTIVE: To examine the association of six glutathione transferase (GST gene polymorphisms (GSTT1, GSTP1/rs1695, GSTO1/rs4925, GSTO2/rs156697, GSTM1, GSTA1/rs3957357 with the survival of patients with muscle invasive bladder cancer and the genotype modifying effect on chemotherapy. PATIENTS AND METHODS: A total of 105 patients with muscle invasive bladder cancer were included in the study. The follow-up lasted 5 years. The effect of GSTs polymorphisms on predicting mortality was analyzed by the Cox proportional hazard models, while Kaplan-Meier analysis was performed to assess differences in survival. RESULTS: GSTT1 active, GSTO1 Asp140Asp or GSTO2 Asp142Asp genotypes were independent predictors of a higher risk of death among bladder cancer patients (HR = 2.5, P = 0.028; HR = 2.9, P = 0.022; HR = 3.9, P = 0.001; respectively and significantly influenced the overall survival. There was no association between GSTP1, GSTM1 and GSTA1 gene variants with overall mortality. Only GSTO2 polymorphism showed a significant effect on the survival in the subgroup of patients who received chemotherapy (P = 0.006. CONCLUSION: GSTT1 active genotype and GSTO1 Asp140Asp and GSTO2 Asp142Asp genotypes may have a prognostic/pharmacogenomic role in patients with muscle invasive bladder cancer.

Humanizing π-class glutathione S-transferase regulation in a mouse model alters liver toxicity in response to acetaminophen overdose.

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Matthew P Vaughn

Full Text Available Glutathione S-transferases (GSTs metabolize drugs and xenobiotics. Yet despite high protein sequence homology, expression of π-class GSTs, the most abundant of the enzymes, varies significantly between species. In mouse liver, hepatocytes exhibit high mGstp expression, while in human liver, hepatocytes contain little or no hGSTP1 mRNA or hGSTP1 protein. π-class GSTs are known to be critical determinants of liver responses to drugs and toxins: when treated with high doses of acetaminophen, mGstp1/2+/+ mice suffer marked liver damage, while mGstp1/2-/- mice escape liver injury.To more faithfully model the contribution of π-class GSTs to human liver toxicology, we introduced hGSTP1, with its exons, introns, and flanking sequences, into the germline of mice carrying disrupted mGstp genes. In the resultant hGSTP1+mGstp1/2-/- strain, π-class GSTs were regulated differently than in wild-type mice. In the liver, enzyme expression was restricted to bile duct cells, Kupffer cells, macrophages, and endothelial cells, reminiscent of human liver, while in the prostate, enzyme production was limited to basal epithelial cells, reminiscent of human prostate. The human patterns of hGSTP1 transgene regulation were accompanied by human patterns of DNA methylation, with bisulfite genomic sequencing revealing establishment of an unmethylated CpG island sequence encompassing the gene promoter. Unlike wild-type or mGstp1/2-/- mice, when hGSTP1+mGstp1/2-/- mice were overdosed with acetaminophen, liver tissues showed limited centrilobular necrosis, suggesting that π-class GSTs may be critical determinants of toxin-induced hepatocyte injury even when not expressed by hepatocytes.By recapitulating human π-class GST expression, hGSTP1+mGstp1/2-/- mice may better model human drug and xenobiotic toxicology.

Genetic polymorphism in three glutathione s-transferase genes and breast cancer risk

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Woldegiorgis, S.; Ahmed, R.C.; Zhen, Y.; Erdmann, C.A.; Russell, M.L.; Goth-Goldstein, R.

2002-04-01

The role of the glutathione S-transferase (GST) enzyme family is to detoxify environmental toxins and carcinogens and to protect organisms from their adverse effects, including cancer. The genes GSTM1, GSTP1, and GSTT1 code for three GSTs involved in the detoxification of carcinogens, such as polycyclic aromatic hydrocarbons (PAHs) and benzene. In humans, GSTM1 is deleted in about 50% of the population, GSTT1 is absent in about 20%, whereas the GSTP1 gene has a single base polymorphism resulting in an enzyme with reduced activity. Epidemiological studies indicate that GST polymorphisms increase the level of carcinogen-induced DNA damage and several studies have found a correlation of polymorphisms in one of the GST genes and an increased risk for certain cancers. We examined the role of polymorphisms in genes coding for these three GST enzymes in breast cancer. A breast tissue collection consisting of specimens of breast cancer patients and non-cancer controls was analyzed by polymerase chain reaction (PCR) for the presence or absence of the GSTM1 and GSTT1 genes and for GSTP1 single base polymorphism by PCR/RFLP. We found that GSTM1 and GSTT1 deletions occurred more frequently in cases than in controls, and GSTP1 polymorphism was more frequent in controls. The effective detoxifier (putative low-risk) genotype (defined as presence of both GSTM1 and GSTT1 genes and GSTP1 wild type) was less frequent in cases than controls (16% vs. 23%, respectively). The poor detoxifier (putative high-risk) genotype was more frequent in cases than controls. However, the sample size of this study was too small to provide conclusive results.

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

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

2015-01-01

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

Genetic polymorphisms of GSTM1, GSTT1, and GSTP1 with prostate cancer risk: a meta-analysis of 57 studies.

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Mancheng Gong

Full Text Available BACKGROUND AND OBJECTIVES: The GSTM1, GSTT1 and GSTP1 polymorphisms might be involved in inactivation of procarcinogens that contribute to the genesis and progression of cancers. However, studies investigating the association between GSTM1, GSTT1 or GSTP1 polymorphisms and prostate cancer (PCa risk report conflicting results, therefore, we conducted a meta-analysis to re-examine the controversy. METHODS: Published literature from PubMed, Embase, Google Scholar and China National Knowledge Infrastructure (CNKI were searched (updated to June 2, 2012. According to our inclusion criteria, studies that observed the association between GSTM1, GSTT1 or GSTP1 polymorphisms and PCa risk were included. The principal outcome measure was the odds ratio (OR with 95% confidence interval (CI for the risk of PCa associated with GSTM1, GSTT1 and GSTP1 polymorphisms. RESULTS: Fifty-seven studies involving 11313 cases and 12934 controls were recruited. The overall OR, which was 1.2854 (95% CI = 1.1405-1.4487, revealed a significant risk of PCa and GSTM1 null genotype, and the similar results were observed when stratified by ethnicity and control source. Further, the more important is that the present study first reported the high risks of PCa for people who with dual null genotype of GSTM1 and GSTT1 (OR = 1.4353, 95% CI = 1.0345-1.9913, or who with GSTT1 null genotype and GSTP1 A131G polymorphism (OR = 1.7335, 95% CI = 1.1067-2.7152. But no association was determined between GSTT1 null genotype (OR = 1.102, 95% CI = 0.9596-1.2655 or GSTP1 A131G polymorphism (OR = 1.0845, 95% CI = 0.96-1.2251 and the PCa risk. CONCLUSIONS: Our meta-analysis suggested that the people with GSTM1 null genotype, with dual null genotype of GSTM1 and GSTT1, or with GSTT1 null genotype and GSTP1 A131G polymorphism are associated with high risks of PCa, but no association was found between GSTT1 null genotype or GSTP1 A131G polymorphism and the risk of

RESEARCH ARTICLE Association of GSTM1, GSTT1 and GSTP1 ...

Indian Academy of Sciences (India)

2017-01-12

Jan 12, 2017 ... Subject Recruitment. This study was started after getting ethical approval from Research and Ethics Committee of ..... LeukemiaNet recommendations for the management of CML. Ann Hematol, 94(2) ... Identification of class-mu glutathione transferase genes GSTM1-GSTM5 on human chromosome 1p13.

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.

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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.

Promoter-region hypermethylation and expression downregulation of Yy1 (Yin yang 1) in preneoplastic liver lesions in a thioacetamide rat hepatocarcinogenesis model

International Nuclear Information System (INIS)

Abe, Hajime; Ogawa, Takashi; Wang, Liyun; Kimura, Masayuki; Tanaka, Takeshi; Morita, Reiko; Yoshida, Toshinori; Shibutani, Makoto

2014-01-01

Thioacetamide (TAA) has been used to develop a rodent model for hepatocarcinogenesis. To determine the genes with epigenetic modifications in early hepatocarcinogenesis, we did a genome-wide scan for hypermethylated promoter regions using CpG island microarrays in TAA-promoted rat liver tissue. Eight genes were selected based on the microarray profile; of these, Yy1 and Wdr45b were confirmed to be hypermethylated by methylation-specific polymerase chain reaction (PCR) and pyrosequencing and downregulated by real-time reverse transcription PCR. Non-neoplastic liver cells had nuclear Yy1 immunoreactivity, while preneoplastic foci with glutathione S-transferase placental form (GST-P) immunoreactivity had decreased Yy1 immunoreactivity. The incidence of these foci was proportional to the dose of TAA administered. Co-expression analysis of gene products downstream of Yy1 revealed increased nuclear phospho-c-Myc + foci as well as nuclear and cytoplasmic p21 Cip1+ foci in Yy1 − or GST-P + foci in response to TAA-promotion dose. Although the absolute number of cells was low, the incidence of death receptor 5 − foci was increased in Yy1 − foci in proportion to the TAA dose. Yy1 − /GST-P + foci revealed a higher number of proliferating cell nuclear antigen (PCNA)-immunoreactive cells than Yy1 + /GST-P + foci, while cleaved caspase-3 + cells were unchanged between Yy1 – /GST-P + and Yy1 + /GST-P + foci. In the case of Wdr45b, most GST-P + foci were Wdr45b – and were not increased by TAA promotion. These results suggest involvement of Yy1 in the epigenetic gene regulation at the early stages of TAA promoted cell proliferation and concomitant cell cycle arrest in preneoplastic lesions. - Highlights: • Epigenetically downregulated genes were searched in TAA-promnoted rat livers. • Yy1 and Wdr45b showed promoter-region hypermethylation and mRNA downregulation. • TAA promoted increase of preneoplastic Yy1 – /GST-P + foci showing high proliferation. • TAA

Transformation of alkylating regimen of thiotepa into tepa determines the disease progression through GSTP1 gene polymorphism for metastatic breast cancer patients receiving thiotepa containing salvage chemotherapy.

Science.gov (United States)

Zhou, Xinna; Wang, Xiaoli; Song, Qingkun; Yang, Huabing; Zhu, Xishan; Yu, Jing; Song, Guohong; Di, Lijun; Ren, Jun; Shao, Hong; Lyerly, Herbert Kim

2015-11-01

The shifts to second-line chemotherapy for metastatic breast cancer (MBC) were widely required based on pharmaceutical molecular profiles to reach out precision medicine. The emerging precise treatment of cancer requires the implementation of clarified pharmacogenetic profiles which are capable of elucidating the predictive responses to cancer chemotherapy. Therefore we were interested in the analysis of the roles of single nucleotide polymorphism (SNP) of GSTP1 (glutathione S-transferase pi 1 gene) alleles to identify pharmacological links with predictors of clinical responses and toxicities. 93 MBC patients receiving thiotepa plus docetaxel chemotherapy were enrolled in this study. Optimized CYP3A5, CYP2B6, and GSTP1 were predominantly selected as candidate genes and their three SNPs (CYP2B6 G516T, CYP3A5 A6986G, and GSTP1 A313G) were genotyped by matrix-assisted laser desorption ionization/time of flight (MALDI-TOF) mass spectrometry. Progression-free survival (PFS), disease control rate, and chemo-related toxicities were recorded. GSTP1 A313G (rs1695) was identified to be related with disease progression. In particular, patients harboring AG/GG genotype demonstrated a statistically longer PFS than those with AA. Multivariate analysis confirmed that AG/GG genotype was associated with both clinical responses and liver-localized metastatic lesions. No correlation was found between these three SNPs and chemotherapy-induced toxicity. These results suggest that the GSTP1 polymorphism is a novel prognostic marker for clinical response to thiotepa-containing chemotherapy regimens. Such evidence could provide insight into the role of pharmacogenetics to deprive of biases in shifting regimens solely by empirical choices.

Examination of polymorphic glutathione S-transferase (GST) genes, tobacco smoking and prostate cancer risk among Men of African Descent: A case-control study

International Nuclear Information System (INIS)

Lavender, Nicole A; Benford, Marnita L; VanCleave, Tiva T; Brock, Guy N; Kittles, Rick A; Moore, Jason H; Hein, David W; Kidd, La Creis R

2009-01-01

Polymorphisms in glutathione S-transferase (GST) genes may influence response to oxidative stress and modify prostate cancer (PCA) susceptibility. These enzymes generally detoxify endogenous and exogenous agents, but also participate in the activation and inactivation of oxidative metabolites that may contribute to PCA development. Genetic variations within selected GST genes may influence PCA risk following exposure to carcinogen compounds found in cigarette smoke and decreased the ability to detoxify them. Thus, we evaluated the effects of polymorphic GSTs (M1, T1, and P1) alone and combined with cigarette smoking on PCA susceptibility. In order to evaluate the effects of GST polymorphisms in relation to PCA risk, we used TaqMan allelic discrimination assays along with a multi-faceted statistical strategy involving conventional and advanced statistical methodologies (e.g., Multifactor Dimensionality Reduction and Interaction Graphs). Genetic profiles collected from 873 men of African-descent (208 cases and 665 controls) were utilized to systematically evaluate the single and joint modifying effects of GSTM1 and GSTT1 gene deletions, GSTP1 105 Val and cigarette smoking on PCA risk. We observed a moderately significant association between risk among men possessing at least one variant GSTP1 105 Val allele (OR = 1.56; 95%CI = 0.95-2.58; p = 0.049), which was confirmed by MDR permutation testing (p = 0.001). We did not observe any significant single gene effects among GSTM1 (OR = 1.08; 95%CI = 0.65-1.82; p = 0.718) and GSTT1 (OR = 1.15; 95%CI = 0.66-2.02; p = 0.622) on PCA risk among all subjects. Although the GSTM1-GSTP1 pairwise combination was selected as the best two factor LR and MDR models (p = 0.01), assessment of the hierarchical entropy graph suggested that the observed synergistic effect was primarily driven by the GSTP1 Val marker. Notably, the GSTM1-GSTP1 axis did not provide additional information gain when compared to either loci alone based on a

THE EFFECT OF POLYMORPHISM IN GLUTATHIONE S-TRANSFERASES ON THE DEVELOPING SECOND MALIGNANT NEOPLASMS AFTER LEUKEMIA TREATMENT IN CHILDHOOD

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Janez Jazbec

2004-12-01

Full Text Available Background. Survivors of childhood leukemia have an increased risk of developing second malignant neoplasms and specific treatment factors such as alkylating agents, topoisomerase inhibitors and radiation have been associated with their occurrence. Genetic polymorphism in drug-metabolizing enzymes may result in impared detoxification of chemotherapeutics and may lead to increased risk for cancer.Methods. To test if polymorphism in glutathione S-transferases (GST genes is associated with occurrence of secondary malignant neoplasms, we compared GSTM1, GSTT1 and GSTP1 genotypes among 16 patients treated for childhood leukemia in whom second neoplasm occurred and matched the control group.Results. GSTM1 null genotype was found in 44% of patients with second neoplasms and in 50% in control group (p = 0.768, GSTT1 null genotype in 19% of cases and in 29% of controls (p = 0.729 and GSTP1 105 Ile/ile in 50% of cases and 37% of controls (p = 0.537. Differences in distribution of GST genotypes in patients with second neoplasms after childhood leukemia, compared to a matched control group of patients were not statistically significant.Conclusions. In our study we were not able to show relation between GST genotype and occurrence of second neoplasms after the childhood acute leukemia.

Glutathione S-transferase M1 and T1, CYP1A2-2467T/delT ...

African Journals Online (AJOL)

The present study investigated the impact of metabolic gene polymorphisms in modulating lung cancer risk susceptibility. Gene polymorphisms encoding Cytochrome 1A2 (CYP1A2) and Glutathione-S-transferases (GSTT1 and GSTM1) are involved in the bioactivation and detoxification of tobacco carcinogens and may ...

The association between glutathione S-transferase P1 ...

African Journals Online (AJOL)

Mahmoud I. Mahmoud

2011-08-10

Aug 10, 2011 ... B-adrenergic receptor polymorphisms and response to salmeterol. Am J Respir Crit Care ... transferase Pi locus and association with susceptibility to bladder, testicular and prostate cancer. Carcinogenesis 1997;18(4):641–4.

Baculovirus-mediated expression and isolation of human ribosomal phosphoprotein P0 carrying a GST-tag in a functional state

International Nuclear Information System (INIS)

Abo, Yohichi; Hagiya, Akiko; Naganuma, Takao; Tohkairin, Yukiko; Shiomi, Kunihiro; Kajiura, Zenta; Hachimori, Akira; Uchiumi, Toshio; Nakagaki, Masao

2004-01-01

We constructed an overexpression system for human ribosomal phosphoprotein P0, together with P1 and P2, which is crucially important for translation. Genes for these proteins, fused with the glutathione S-transferase (GST)-tag at the N-terminus, were inserted into baculovirus and introduced to insect cells. The fusion proteins, but not the proteins without the tag, were efficiently expressed into cells as soluble forms. The fusion protein GST.P0 as well as GST.P1/GST.P2 was phosphorylated in cells as detected by incorporation of 32 P and reactivity with monoclonal anti-phosphoserine antibody. GST.P0 expressed in insect cells, but not the protein obtained in Escherichia coli, had the ability to form a complex with P1 and P2 proteins and to bind to 28S rRNA. Moreover, the GST.P0-P1-P2 complex participated in high eEF-2-dependent GTPase activity. Baculovirus expression systems appear to provide recombinant human P0 samples that can be used for studies on the structure and function

Mitochondrial control region and GSTP1 polymorphism associated ...

African Journals Online (AJOL)

Souvik Ghatak

2016-02-20

Feb 20, 2016 ... were identified in urinary bladder cancer samples in GSTP1 gene. These two heteroplasmic ... also develop into a genetic marker of hereditary urinary blad- der cancer. ..... loop region in human colorectal cancer. Dis Colon ...

Association of GSTP1 gene polymorphisms with performance traits ...

African Journals Online (AJOL)

sony

2000). However, along with heat shock proteins (HSPs), it is estimated that ... Bangalore, India to amplify the GSTP1 gene fragments (Table 1). The PCR-SSCP ... after collection of blood samples in a vacutainer tube contatining. 0.5% EDTA.

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

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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 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.

Study of the Role of siRNA Mediated Promoter Methylation in DNMT3B Knockdown and Alteration of Promoter Methylation of CDH1, GSTP1 Genes in MDA-MB -453 Cell Line.

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Naghitorabi, Mojgan; Mir Mohammad Sadeghi, Hamid; Mohammadi Asl, Javad; Rabbani, Mohammad; Jafarian-Dehkordi, Abbas

2017-01-01

Promoter methylation is one of the main epigenetic mechanisms that leads to the inactivation of tumor suppressor genes during carcinogenesis. Due to the reversible nature of DNA methylation, many studies have been performed to correct theses epigenetic defects by inhibiting DNA methyltransferases (DNMTs). In this case novel therapeutics especially siRNA oligonucleotides have been used to specifically knock down the DNMTs at mRNA level. Also many studies have focused on transcriptional gene silencing in mammalian cells via siRNA mediated promoter methylation. The present study was designed to assess the role of siRNA mediated promoter methylation in DNMT3B knockdown and alteration of promoter methylation of Cadherin-1 (CDH1), Glutathione S-Transferase Pi 1(GSTP1), and DNMT3B genes in MDA-MB-453 cell line. MDA-MB-453 cells were transfected with siDNMT targeting DNMT3B promoter and harvested at 24 and 48 h post transfection to monitor gene silencing and promoter methylation respectively. DNMT3B expression was monitored by quantitative RT-PCR method. Promoter methylation was quantitatively evaluated using differential high resolution melting analysis. A non-significant 20% reduction in DNMT3B mRNA level was shown only after first transfection with siDNMT, which was not reproducible. Promoter methylation levels of DNMT3B, CDH1, and GSTP1 were detected at about 15%, 70% and 10% respectively, in the MDA-MB-453 cell line, with no significant change after transfection. Our results indicated that siDNMT sequence were not able to affect promoter methylation and silencing of DNMT3B in MDA-MB-453 cells. However, quantitation of methylation confirmed a hypermethylated phenotype at CDH1 and GSTP1 promoters as well as a differential methylation pattern at DNMT3B promoter in breast cancer.

Association of GSTP1 gene polymorphisms with performance traits ...

African Journals Online (AJOL)

sony

The genetic variants were determined by PCR-SSCP technique. Two unique SSCP patterns were observed in fragment 1, 3, 5 and 6 of GSTP1 gene. Sequence analysis with reference to GenBank. Acc. no AC_000186.1 revealed polymorphisms at position 210, 746, 2438, 2439, 2443, 2507, 2695 and insertions between ...

Detection of GSTM1, GSTT1 and the Ile105Val GSTP1 gene variants

DEFF Research Database (Denmark)

Buchard, Anders; Sanchez, Juan J.; Dalhoff, Kim

2008-01-01

We have developed a PCR multiplex method that in a fast, inexpensive and reliable manner can detect if a person has two, one or no GSTM1 and GSTT1 genes and which at the same time can detect the allelic status of the GSTP1 Ile105Val genetic variant. A total of 200 Danes, 100 Somalis and 100...

[The association between genetic polymorphisms of GSTM1, GSTT1, GSTP1 and susceptibility to laryngeal carcinoma from the Han people in Guangdong zone].

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Tian, Shenzhi; Zhang, Jianguo; Xiao, Qi; Zhai, Jinming; Yan, Xiaoling; Huang, Minqi; Chen, Fujin; Li, Qiuli; Guan, Zhong

2011-03-01

To analyze the association between genetic polymorphisms of xenobiotic- metabolizing enzymes GSTM1, GSTT1, GSTP1 and susceptibility to laryngeal carcinoma from the Han people in Guangdong zone. A case-control study was conducted involving 233 LSCC (laryngeal squamous cell carcinoma) patients and 102 healthy controls to investigate the association between polymorphisms of GSTM1, GSTT1, GSTP1 (Ile/Val) and LSCC from the Han people in Guangdong zone. All blood samples of the Han people from the Guangdong zone was analyzed with methods of PCR, ASA and the DNA sequencing technique with sequenator. We explored the association between polymorphisms and the clinical pathologic characteristics of LSCC. The data was processed with SPSS13.0. Odds Ratios (ORs) with 95% CI for relevancy intensity were calculated using binary logistic regression analysis. The frequency of GSTM1(-) and GSTT1(-) genotype was higher in LSCC than that in healthy controls (OR = 2.61, 3.05, P 51, 95% CI 2.05-5.01; OR = 2.99, 95% CI 2.00-4.49). The frequency of GSTM1(-) and GSTT1(-) genotype was higher in LSCC whose family had carcinoma history. The frequency of advanced LSCC was higher in patients who were with GSTM1(-) and GSTT1 (-) genotype (P 0.05). There may be an association between the susceptibility to carcinoma and GSTT1(-), GSTM1(-) genotype. The GSTT1(-) polymorphism c gene cooperating with heavily smoking boost up the susceptibility of individual to laryngeal carcinoma. The GSTM1(-) polymorphism c may not cooperating with smoking during carcinogenesis of LSCC in the Han people in Guangdong zone. The morphisms of GSTT1 and GSTM1 gene may affect the carcino-genesis of LSCC in the Han people in Guangdong zone. There may be no association between the susceptibility to laryngeal carcinoma and the GSTP1(Ile/Val) type.

Mitochondrial control region and GSTP1 polymorphism associated ...

African Journals Online (AJOL)

These two heteroplasmic mutations were found at positions 11qG3037G/A and 11qC3038C/A in patient, father, mother, brother and son, but not in the sister and wife samples in family 2. The GSTP1, 105Ile >Val is most susceptible to inherited UBC risk for these ethnic families. The samples from families 1 and 2, including ...

Role of XPC, XPD, XRCC1, GSTP genetic polymorphisms and Barrett’s esophagus in a cohort of Italian subjects. A neural network analysis

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Tarlarini C

2012-08-01

Full Text Available Claudia Tarlarini,1 Silvana Penco,1 Massimo Conio,2 Enzo Grossi3 On behalf of the Barrett Italian Study Group 1Department of Laboratory Medicine, Medical Genetics, Niguarda Ca’ Granda Hospital, Milan, Italy; 2Department of Gastroenterology, General Hospital, San Remo, Italy; 3Medical Department, Bracco Imaging SpA, Milan, ItalyBackground: Barrett’s esophagus (BE, a metaplastic premalignant disorder, represents the primary risk factor for the development of esophageal adenocarcinoma. Chronic gastroesophageal reflux disease and central obesity have been associated with BE and esophageal adenocarcinoma, but relatively little is known about the specific genes that confer susceptibility to BE carcinogenesis.Methods: A total of 74 patients with BE and 67 controls coming from six gastrointestinal Italian units were evaluated for six polymorphisms in four genes: XPC, XPD nucleotide excision repair (NER genes, XRCC1 (BER gene, and glutathione S-transferase P1. Smoking status was analyzed together with the genetic data. Statistical analysis was performed through Artificial Neural Networks.Results: Distributions of sex, smoking history, and polymorphisms among BE cases and controls did not show statistically significant differences. The r-value from linear correlation allowed us to identify possible protective factors as well as possible risk factors. The application of advanced intelligent systems allowed for the selection of a subgroup of nine variables. Artificial Neural Networks applied on the final data set reached mean global accuracy of 60%, reaching as high as 65.88%.Conclusion: We report here results from an exploratory study. Results from this study failed to find an association among the tested single nucleotide polymorphisms and BE phenotype through classical statistical methods. On the contrary, advanced intelligent systems are really able to handle the disease complexity, not treating the data with reductionist approaches unable to detect

Sulforaphane and alpha-lipoic acid upregulate the expression of the pi class of glutathione S-transferase through c-jun and Nrf2 activation.

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Lii, Chong-Kuei; Liu, Kai-Li; Cheng, Yi-Ping; Lin, Ai-Hsuan; Chen, Haw-Wen; Tsai, Chia-Wen

2010-05-01

The anticarcinogenic effect of dietary organosulfur compounds has been partly attributed to their modulation of the activity and expression of phase II detoxification enzymes. Our previous studies indicated that garlic allyl sulfides upregulate the expression of the pi class of glutathione S-transferase (GSTP) through the activator protein-1 pathway. Here, we examined the modulatory effect of sulforaphane (SFN) and alpha-lipoic acid (LA) or dihydrolipoic acid (DHLA) on GSTP expression in rat Clone 9 liver cells. Cells were treated with LA or DHLA (50-600 micromol/L) or SFN (0.2-5 micromol/L) for 24 h. Immunoblots and real-time PCR showed that SFN, LA, and DHLA dose dependently induced GSTP protein and mRNA expression. Compared with the induction by the garlic organosulfur compound diallyl trisulfide (DATS), the effectiveness was in the order of SFN > DATS > LA = DHLA. The increase in GSTP enzyme activity in cells treated with 5 micromol/L SFN, 50 micromol/L DATS, and 600 micromol/L LA and DHLA was 172, 75, 122, and 117%, respectively (P GPEI) was required for GSTP induction by the organosulfur compounds. Electromobility gel shift assays showed that the DNA binding of GPEI to nuclear proteins reached a maximum at 0.5-1 h after SFN, LA, and DHLA treatment. Super-shift assay revealed that the transcription factors c-jun and nuclear factor erythroid-2 related factor 2 (Nrf2) were bound to GPEI. These results suggest that SFN and LA in either its oxidized or reduced form upregulate the transcription of the GSTP gene by activating c-jun and Nrf2 binding to the enhancer element GPEI.

Genetic polymorphisms in CYP1A1, GSTM1, GSTP1 and GSTT1 metabolic genes and risk of lung cancer in Asturias

International Nuclear Information System (INIS)

López-Cima, M Felicitas; Álvarez-Avellón, Sara M; Pascual, Teresa; Fernández-Somoano, Ana; Tardón, Adonina

2012-01-01

Metabolic genes have been associated with the function of metabolizing and detoxifying environmental carcinogens. Polymorphisms present in these genes could lead to changes in their metabolizing and detoxifying ability and thus may contribute to individual susceptibility to different types of cancer. We investigated if the individual and/or combined modifying effects of the CYP1A1 MspI T6235C, GSTM1 present/null, GSTT1 present/null and GSTP1 Ile105Val polymorphisms are related to the risk of developing lung cancer in relation to tobacco consumption and occupation in Asturias, Northern Spain. A hospital-based case–control study (CAPUA Study) was designed including 789 lung cancer patients and 789 control subjects matched in ethnicity, age, sex, and hospital. Genotypes were determined by PCR or PCR-RFLP. Individual and combination effects were analysed using an unconditional logistic regression adjusting for age, pack-years, family history of any cancer and occupation. No statistically significant main effects were observed for the carcinogen metabolism genes in relation to lung cancer risk. In addition, the analysis did not reveal any significant gene-gene, gene-tobacco smoking or gene-occupational exposure interactions relative to lung cancer susceptibility. Lastly, no significant gene-gene combination effects were observed. These results suggest that genetic polymorphisms in the CYP1A1, GSTM1, GSTT1 and GSTP1 metabolic genes were not significantly associated with lung cancer risk in the current study. The results of the analysis of gene-gene interactions of CYP1A1 MspI T6235C, GSTM1 present/null, GSTT1 present/null and GSTP1 Ile105Val polymorphisms in lung cancer risk indicate that these genes do not interact in lung cancer development

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

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Chin-Soon Chee

2014-01-01

Full Text Available 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.

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

Science.gov (United States)

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

Pharmacogenetic Study in Rectal Cancer Patients Treated With Preoperative Chemoradiotherapy: Polymorphisms in Thymidylate Synthase, Epidermal Growth Factor Receptor, GSTP1, and DNA Repair Genes

International Nuclear Information System (INIS)

Páez, David; Salazar, Juliana; Paré, Laia; Pertriz, Lourdes; Targarona, Eduardo; Rio, Elisabeth del; Barnadas, Agusti; Marcuello, Eugenio; Baiget, Montserrat

2011-01-01

Purpose: Several studies have been performed to evaluate the usefulness of neoadjuvant treatment using oxaliplatin and fluoropyrimidines for locally advanced rectal cancer. However, preoperative biomarkers of outcome are lacking. We studied the polymorphisms in thymidylate synthase, epidermal growth factor receptor, glutathione S-transferase pi 1 (GSTP1), and several DNA repair genes to evaluate their usefulness as pharmacogenetic markers in a cohort of 128 rectal cancer patients treated with preoperative chemoradiotherapy. Methods and Materials: Blood samples were obtained from 128 patients with Stage II-III rectal cancer. DNA was extracted from the peripheral blood nucleated cells, and the genotypes were analyzed by polymerase chain reaction amplification and automated sequencing techniques or using a 48.48 dynamic array on the BioMark system. The germline polymorphisms studied were thymidylate synthase, (VNTR/5′UTR, 2R G>C single nucleotide polymorphism [SNP], 3R G>C SNP), epidermal growth factor receptor (Arg497Lys), GSTP1 (Ile105val), excision repair cross-complementing 1 (Asn118Asn, 8092C>A, 19716G>C), X-ray repair cross-complementing group 1 (XRCC1) (Arg194Trp, Arg280His, Arg399Gln), and xeroderma pigmentosum group D (Lys751Gln). The pathologic response, pathologic regression, progression-free survival, and overall survival were evaluated according to each genotype. Results: The ∗3/∗3 thymidylate synthase genotype was associated with a greater response rate (pathologic complete remission and microfoci residual tumor, 59% in ∗3/∗3 vs. 35% in ∗2/∗2 and ∗2/∗3; p = .013). For the thymidylate synthase genotype, the median progression-free survival was 103 months for the ∗3/∗3 patients and 84 months for the ∗2/∗2 and ∗2/∗3 patients (p = .039). For XRCC1 Arg399Gln SNP, the median progression-free survival was 101 months for the G/G, 78 months for the G/A, and 31 months for the A/A patients (p = .048). Conclusions: The thymidylate

Pharmacogenetic Study in Rectal Cancer Patients Treated With Preoperative Chemoradiotherapy: Polymorphisms in Thymidylate Synthase, Epidermal Growth Factor Receptor, GSTP1, and DNA Repair Genes

Energy Technology Data Exchange (ETDEWEB)

Paez, David, E-mail: dpaez@santpau.cat [Department of Medical Oncology, Hospital de la Santa Creu i Sant Pau, Universitat Autonoma de Barcelona, Barcelona (Spain); Salazar, Juliana; Pare, Laia [Centre for Biomedical Network Research on Rare Diseases, Barcelona (Spain); Department of Genetics, Hospital de la Santa Creu i Sant Pau, Universitat Autonoma de Barcelona, Barcelona (Spain); Pertriz, Lourdes [Department of Radiotherapy, Hospital de la Santa Creu i Sant Pau, Universitat Autonoma de Barcelona, Barcelona (Spain); Targarona, Eduardo [Department of Surgery, Hospital de la Santa Creu i Sant Pau, Universitat Autonoma de Barcelona, Barcelona (Spain); Rio, Elisabeth del [Centre for Biomedical Network Research on Rare Diseases, Barcelona (Spain); Department of Genetics, Hospital de la Santa Creu i Sant Pau, Universitat Autonoma de Barcelona, Barcelona (Spain); Barnadas, Agusti; Marcuello, Eugenio [Department of Medical Oncology, Hospital de la Santa Creu i Sant Pau, Universitat Autonoma de Barcelona, Barcelona (Spain); Baiget, Montserrat [Centre for Biomedical Network Research on Rare Diseases, Barcelona (Spain); Department of Genetics, Hospital de la Santa Creu i Sant Pau, Universitat Autonoma de Barcelona, Barcelona (Spain)

2011-12-01

Purpose: Several studies have been performed to evaluate the usefulness of neoadjuvant treatment using oxaliplatin and fluoropyrimidines for locally advanced rectal cancer. However, preoperative biomarkers of outcome are lacking. We studied the polymorphisms in thymidylate synthase, epidermal growth factor receptor, glutathione S-transferase pi 1 (GSTP1), and several DNA repair genes to evaluate their usefulness as pharmacogenetic markers in a cohort of 128 rectal cancer patients treated with preoperative chemoradiotherapy. Methods and Materials: Blood samples were obtained from 128 patients with Stage II-III rectal cancer. DNA was extracted from the peripheral blood nucleated cells, and the genotypes were analyzed by polymerase chain reaction amplification and automated sequencing techniques or using a 48.48 dynamic array on the BioMark system. The germline polymorphisms studied were thymidylate synthase, (VNTR/5 Prime UTR, 2R G>C single nucleotide polymorphism [SNP], 3R G>C SNP), epidermal growth factor receptor (Arg497Lys), GSTP1 (Ile105val), excision repair cross-complementing 1 (Asn118Asn, 8092C>A, 19716G>C), X-ray repair cross-complementing group 1 (XRCC1) (Arg194Trp, Arg280His, Arg399Gln), and xeroderma pigmentosum group D (Lys751Gln). The pathologic response, pathologic regression, progression-free survival, and overall survival were evaluated according to each genotype. Results: The Asterisk-Operator 3/ Asterisk-Operator 3 thymidylate synthase genotype was associated with a greater response rate (pathologic complete remission and microfoci residual tumor, 59% in Asterisk-Operator 3/ Asterisk-Operator 3 vs. 35% in Asterisk-Operator 2/ Asterisk-Operator 2 and Asterisk-Operator 2/ Asterisk-Operator 3; p = .013). For the thymidylate synthase genotype, the median progression-free survival was 103 months for the Asterisk-Operator 3/ Asterisk-Operator 3 patients and 84 months for the Asterisk-Operator 2/ Asterisk-Operator 2 and Asterisk-Operator 2/ Asterisk

Association study on glutathione S-transferase omega 1 and 2 and familial ALS

NARCIS (Netherlands)

van de Giessen, Elsmarieke; Fogh, Isabella; Gopinath, Sumana; Smith, Bradley; Hu, Xun; Powell, John; Andersen, Peter; Nicholson, Garth; Al Chalabi, Ammar; Shaw, Christopher E.

2008-01-01

Glutathione S-transferase omega 1 and 2 (GSTO1 and 2) protect from oxidative stress, a possible pathogenic mechanism underlying the pathogenesis of neurodegenerative diseases such as amyotrophic lateral sclerosis (ALS) and Alzheimer's disease. Significant association of age of onset in Alzheimer's

Activation of Nrf2 is required for up-regulation of the π class of glutathione S-transferase in rat primary hepatocytes with L-methionine starvation.

Science.gov (United States)

Lin, Ai-Hsuan; Chen, Haw-Wen; Liu, Cheng-Tze; Tsai, Chia-Wen; Lii, Chong-Kuei

2012-07-04

Numerous genes expression is regulated in response to amino acid shortage, which helps organisms adapt to amino acid limitation. The expression of the π class of glutathione (GSH) S-transferase (GSTP), a highly inducible phase II detoxification enzyme, is regulated mainly by activates activating protein 1 (AP-1) binding to the enhancer I of GSTP (GPEI). Here we show the critical role of nuclear factor erythroid-2-related factor 2 (Nrf2) in up-regulating GSTP gene transcription. Primary rat hepatocytes were cultured in a methionine-restricted medium, and immunoblotting and RT-PCR analyses showed that methionine restriction time-dependently increased GSTP protein and mRNA expression over a 48 h period. Nrf2 translocation to the nucleus, nuclear proteins binding to GPEI, and antioxidant response element (ARE) luciferase reporter activity were increased by methionine restriction as well as by l-buthionine sulfoximine (BSO), a GSH synthesis inhibitor. Transfection with Nrf2 siRNA knocked down Nrf2 expression and reversed the methionine-induced GSTP expression and GPEI binding activity. Chromatin immunoprecipitation assay confirmed the binding of Nrf2 to the GPEI. Phosphorylation of extracellular signal-regulated kinase 2 (ERK2) was increased in methionine-restricted and BSO-treated cells. ERK2 siRNA abolished methionine restriction-induced Nrf2 nuclear translocation, GPEI binding activity, ARE-luciferase reporter activity, and GSTP expression. Our results suggest that the up-regulation of GSTP gene transcription in response to methionine restriction likely occurs via the ERK-Nrf2-GPEI signaling pathway.

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

International Nuclear Information System (INIS)

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

2009-01-01

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

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

Science.gov (United States)

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

2009-11-30

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

Disruptive cell cycle regulation involving epigenetic downregulation of Cdkn2a (p16Ink4a) in early-stage liver tumor-promotion facilitating liver cell regeneration in rats

International Nuclear Information System (INIS)

Tsuchiya, Takuma; Wang, Liyun; Yafune, Atsunori; Kimura, Masayuki; Ohishi, Takumi; Suzuki, Kazuhiko; Mitsumori, Kunitoshi; Shibutani, Makoto

2012-01-01

Cell cycle aberration was immunohistochemically examined in relation to preneoplastic liver cell foci expressing glutathione S-transferase placental form (GST-P) at early stages of tumor-promotion in rats with thioacetamide (TAA), a hepatocarcinogen facilitating liver cell regeneration. Immunoexpression of p16 Ink4a following exposure to other hepatocarcinogens/promoters and its DNA methylation status were also analyzed during early and late tumor-promotion stages. GST-P + liver cell foci increased cell proliferation and decreased apoptosis when compared with surrounding liver cells. In concordance with GST-P + foci, checkpoint proteins at G 1 /S (p21 Cip1 , p27 Kip1 and p16 Ink4a ) and G 2 /M (phospho-checkpoint kinase 1, Cdc25c and phospho-Wee1) were either up- or downregulated. Cellular distribution within GST-P + foci was either increased or decreased with proteins related to G 2 -M phase or DNA damage (topoisomerase IIα, phospho-histone H2AX, phospho-histone H3 and Cdc2). In particular, p16 Ink4a typically downregulated in GST-P + foci and regenerative nodules at early tumor-promotion stage with hepatocarcinogens facilitating liver cell regeneration and in neoplastic lesions at late tumor-promotion stage with hepatocarcinogens/promoters irrespective of regenerating potential. Hypermethylation at exon 2 of Cdkn2a was detected at both early- and late-stages. Thus, diverse disruptive expression of G 1 /S and G 2 /M proteins, which allows for clonal selection of GST-P + foci, results in the acquisition of multiple aberrant phenotypes to disrupt checkpoint function. Moreover, increased DNA-damage responses within GST-P + foci may be the signature of genetic alterations. Intraexonic hypermethylation may be responsible for p16 Ink4a -downregulation, which facilitates cell cycle progression in early preneoplastic lesions produced by repeated cell regeneration and late-stage neoplastic lesions irrespective of the carcinogenic mechanism.

Genetic polymorphisms in glutathione S-transferase (GST) superfamily and arsenic metabolism in residents of the Red River Delta, Vietnam

International Nuclear Information System (INIS)

Agusa, Tetsuro; Iwata, Hisato; Fujihara, Junko; Kunito, Takashi; Takeshita, Haruo; Tu Binh Minh; Pham Thi Kim Trang; Pham Hung Viet; Tanabe, Shinsuke

2010-01-01

To elucidate the role of genetic factors in arsenic metabolism, we investigated associations of genetic polymorphisms in the members of glutathione S-transferase (GST) superfamily with the arsenic concentrations in hair and urine, and urinary arsenic profile in residents in the Red River Delta, Vietnam. Genotyping was conducted for GST ω1 (GSTO1) Ala140Asp, Glu155del, Glu208Lys, Thr217Asn, and Ala236Val, GST ω2 (GSTO2) Asn142Asp, GST π1 (GSTP1) Ile105Val, GST μ1 (GSTM1) wild/null, and GST θ1 (GSTT1) wild/null. There were no mutation alleles for GSTO1 Glu208Lys, Thr217Asn, and Ala236Val in this population. GSTO1 Glu155del hetero type showed higher urinary concentration of As V than the wild homo type. Higher percentage of DMA V in urine of GSTM1 wild type was observed compared with that of the null type. Strong correlations between GSTP1 Ile105Val and arsenic exposure level and profile were observed in this study. Especially, heterozygote of GSTP1 Ile105Val had a higher metabolic capacity from inorganic arsenic to monomethyl arsenic, while the opposite trend was observed for ability of metabolism from As V to As III . Furthermore, other factors including sex, age, body mass index, arsenic level in drinking water, and genotypes of As (+ 3 oxidation state) methyltransferase (AS3MT) were also significantly co-associated with arsenic level and profile in the Vietnamese. To our knowledge, this is the first study indicating the associations of genetic factors of GST superfamily with arsenic metabolism in a Vietnamese population.

The association of glutathione S-transferase GSTT1 and GSTM1 gene polymorphism with pseudoexfoliative glaucoma in a Pakistani population.

NARCIS (Netherlands)

Khan, M.I.; Micheal, S.; Akhtar, F.; Ahmed, W.; Ijaz, B.; Ahmed, A.; Qamar, R.

2010-01-01

PURPOSE: The aim of the present study was to investigate the association of glutathione S-transferase GSTT1 and GSTM1 genotypes with pseudoexfoliative glaucoma (PEXG) in a group of Pakistani patients. METHODS: Multiplex polymerase chain reaction was used to study the GSTT1 and GSTM1 polymorphisms in

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

International Nuclear Information System (INIS)

Edvardsen, Hege; Kristensen, Vessela N.; Grenaker Alnaes, Grethe Irene B.Sc.; Bohn, Mona; Erikstein, Bjorn; Helland, Aslaug; Borresen-Dale, Anne-Lise; Fossa, Sophie Dorothea

2007-01-01

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

Sphingosine-1-phosphate (S1P) displays sustained S1P1 receptor agonism and signaling through S1P lyase-dependent receptor recycling.

Science.gov (United States)

Gatfield, John; Monnier, Lucile; Studer, Rolf; Bolli, Martin H; Steiner, Beat; Nayler, Oliver

2014-07-01

The sphingosine-1-phosphate (S1P) type 1 receptor (S1P1R) is a novel therapeutic target in lymphocyte-mediated autoimmune diseases. S1P1 receptor desensitization caused by synthetic S1P1 receptor agonists prevents T-lymphocyte egress from secondary lymphoid organs into the circulation. The selective S1P1 receptor agonist ponesimod, which is in development for the treatment of autoimmune diseases, efficiently reduces peripheral lymphocyte counts and displays efficacy in animal models of autoimmune disease. Using ponesimod and the natural ligand S1P, we investigated the molecular mechanisms leading to different signaling, desensitization and trafficking behavior of S1P1 receptors. In recombinant S1P1 receptor-expressing cells, ponesimod and S1P triggered Gαi protein-mediated signaling and β-arrestin recruitment with comparable potency and efficiency, but only ponesimod efficiently induced intracellular receptor accumulation. In human umbilical vein endothelial cells (HUVEC), ponesimod and S1P triggered translocation of the endogenous S1P1 receptor to the Golgi compartment. However, only ponesimod treatment caused efficient surface receptor depletion, receptor accumulation in the Golgi and degradation. Impedance measurements in HUVEC showed that ponesimod induced only short-lived Gαi protein-mediated signaling followed by resistance to further stimulation, whereas S1P induced sustained Gαi protein-mediated signaling without desensitization. Inhibition of S1P lyase activity in HUVEC rendered S1P an efficient S1P1 receptor internalizing compound and abrogated S1P-mediated sustained signaling. This suggests that S1P lyase - by facilitating S1P1 receptor recycling - is essential for S1P-mediated sustained signaling, and that synthetic agonists are functional antagonists because they are not S1P lyase substrates. Copyright © 2014 Elsevier Inc. All rights reserved.

Blocking S1P interaction with S1P1 receptor by a novel competitive S1P1-selective antagonist inhibits angiogenesis

International Nuclear Information System (INIS)

Fujii, Yasuyuki; Ueda, Yasuji; Ohtake, Hidenori; Ono, Naoya; Takayama, Tetsuo; Nakazawa, Kiyoshi; Igarashi, Yasuyuki; Goitsuka, Ryo

2012-01-01

Highlights: ► The effect of a newly developed S1P 1 -selective antagonist on angiogenic responses. ► S1P 1 is a critical component of VEGF-related angiogenic responses. ► S1P 1 -selective antagonist showed in vitro activity to inhibit angiogenesis. ► S1P 1 -selective antagonist showed in vivo activity to inhibit angiogenesis. ► The efficacy of S1P 1 -selective antagonist for anti-cancer therapies. -- Abstract: Sphingosine 1-phosphate receptor type 1 (S1P 1 ) was shown to be essential for vascular maturation during embryonic development and it has been demonstrated that substantial crosstalk exists between S1P 1 and other pro-angiogenic growth factors, such as vascular endothelial growth factor (VEGF) and basic fibroblast growth factor. We developed a novel S1P 1 -selective antagonist, TASP0277308, which is structurally unrelated to S1P as well as previously described S1P 1 antagonists. TASP0277308 inhibited S1P- as well as VEGF-induced cellular responses, including migration and proliferation of human umbilical vein endothelial cells. Furthermore, TASP0277308 effectively blocked a VEGF-induced tube formation in vitro and significantly suppressed tumor cell-induced angiogenesis in vivo. These findings revealed that S1P 1 is a critical component of VEGF-related angiogenic responses and also provide evidence for the efficacy of TASP0277308 for anti-cancer therapies.

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

OpenAIRE

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

1994-01-01

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 ...

Isozyme-specific fluorescent inhibitor of glutathione s-transferase omega 1.

Science.gov (United States)

Son, Junghyun; Lee, Jae-Jung; Lee, Jun-Seok; Schüller, Andreas; Chang, Young-Tae

2010-05-21

Recently, the glutathione S-transferase omega 1 (GSTO1) is suspected to be involved in certain cancers and neurodegenerative diseases. However, profound investigation on the pathological roles of GSTO1 has been hampered by the lack of specific methods to determine or modulate its activity in biological systems containing other isoforms with similar catalytic function. Here, we report a fluorescent compound that is able to inhibit and monitor the activity of GSTO1. We screened 43 fluorescent chemicals and found a compound (6) that binds specifically to the active site of GSTO1. We observed that compound 6 inhibits GSTO1 by covalent modification but spares other isoforms in HEK293 cells and demonstrated that compound 6 could report the activity of GSTO1 in NIH/3T3 or HEK293 cells by measuring the fluorescence intensity of the labeled amount of GSTO1 in SDS-PAGE. Compound 6 is a useful tool to study GSTO1, applicable as a specific inhibitor and an activity reporter.

Regulation and control of nitric oxide (NO) in macrophages

DEFF Research Database (Denmark)

Kovacevic, Zaklina; Sahni, Sumit; Lok, K.H.

2017-01-01

We recently demonstrated that a novel storage and transport mechanism for nitric oxide (NO) mediated by glutathione-S-transferase P1 (GSTP1) and multidrug resistance protein 1 (MRP1/ABCC1), protects M1-macrophage (M1-MØ) models from large quantities of endogenous NO. This system stores and transp......We recently demonstrated that a novel storage and transport mechanism for nitric oxide (NO) mediated by glutathione-S-transferase P1 (GSTP1) and multidrug resistance protein 1 (MRP1/ABCC1), protects M1-macrophage (M1-MØ) models from large quantities of endogenous NO. This system stores...... be responsible for delivering cytotoxic NO as DNICs via MRP1 from M1-MØs, to tumor cell targets....

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

Science.gov (United States)

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

2010-10-01

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

Are glutathione S transferases involved in DNA damage signalling? Interactions with DNA damage and repair revealed from molecular epidemiology studies

International Nuclear Information System (INIS)

Dusinska, Maria; Staruchova, Marta; Horska, Alexandra; Smolkova, Bozena; Collins, Andrew; Bonassi, Stefano; Volkovova, Katarina

2012-01-01

Glutathione S-transferases (GSTs) are members of a multigene family of isoenzymes that are important in the control of oxidative stress and in phase II metabolism. Acting non-enzymically, GSTs can modulate signalling pathways of cell proliferation, cell differentiation and apoptosis. Using a molecular epidemiology approach, we have investigated a potential involvement of GSTs in DNA damage processing, specifically the modulation of DNA repair in a group of 388 healthy adult volunteers; 239 with at least 5 years of occupational exposure to asbestos, stone wool or glass fibre, and 149 reference subjects. We measured DNA damage in lymphocytes using the comet assay (alkaline single cell gel electrophoresis): strand breaks (SBs) and alkali-labile sites, oxidised pyrimidines with endonuclease III, and oxidised purines with formamidopyrimidine DNA glycosylase. We also measured GST activity in erythrocytes, and the capacity for base excision repair (BER) in a lymphocyte extract. Polymorphisms in genes encoding three GST isoenzymes were determined, namely deletion of GSTM1 and GSTT1 and single nucleotide polymorphism Ile105Val in GSTP1. Consumption of vegetables and wine correlated negatively with DNA damage and modulated BER. GST activity correlated with oxidised bases and with BER capacity, and differed depending on polymorphisms in GSTP1, GSTT1 and GSTM1. A significantly lower BER rate was associated with the homozygous GSTT1 deletion in all asbestos site subjects and in the corresponding reference group. Multifactorial analysis revealed effects of sex and exposure in GSTP1 Ile/Val heterozygotes but not in Ile/Ile homozygotes. These variants affected also SBs levels, mainly by interactions of GSTP1 genotype with exposure, with sex, and with smoking habit; and by an interaction between sex and smoking. Our results show that GST polymorphisms and GST activity can apparently influence DNA stability and repair of oxidised bases, suggesting a potential new role for these

Are glutathione S transferases involved in DNA damage signalling? Interactions with DNA damage and repair revealed from molecular epidemiology studies

Energy Technology Data Exchange (ETDEWEB)

Dusinska, Maria, E-mail: Maria.DUSINSKA@nilu.no [CEE-Health Effects Group, NILU - Norwegian Institute for Air Research, Kjeller (Norway); Staruchova, Marta; Horska, Alexandra [Department of Experimental and Applied Genetics, Slovak Medical University, Bratislava (Slovakia); Smolkova, Bozena [Laboratory of Cancer Genetics, Cancer Research Institute of the Slovak Academy of Sciences, Bratislava (Slovakia); Collins, Andrew [Department of Nutrition, Faculty of Medicine, University of Oslo (Norway); Bonassi, Stefano [Unit of Clinical and Molecular Epidemiology, IRCCS San Raffaele Pisana, Rome (Italy); Volkovova, Katarina [Department of Experimental and Applied Genetics, Slovak Medical University, Bratislava (Slovakia)

2012-08-01

Glutathione S-transferases (GSTs) are members of a multigene family of isoenzymes that are important in the control of oxidative stress and in phase II metabolism. Acting non-enzymically, GSTs can modulate signalling pathways of cell proliferation, cell differentiation and apoptosis. Using a molecular epidemiology approach, we have investigated a potential involvement of GSTs in DNA damage processing, specifically the modulation of DNA repair in a group of 388 healthy adult volunteers; 239 with at least 5 years of occupational exposure to asbestos, stone wool or glass fibre, and 149 reference subjects. We measured DNA damage in lymphocytes using the comet assay (alkaline single cell gel electrophoresis): strand breaks (SBs) and alkali-labile sites, oxidised pyrimidines with endonuclease III, and oxidised purines with formamidopyrimidine DNA glycosylase. We also measured GST activity in erythrocytes, and the capacity for base excision repair (BER) in a lymphocyte extract. Polymorphisms in genes encoding three GST isoenzymes were determined, namely deletion of GSTM1 and GSTT1 and single nucleotide polymorphism Ile105Val in GSTP1. Consumption of vegetables and wine correlated negatively with DNA damage and modulated BER. GST activity correlated with oxidised bases and with BER capacity, and differed depending on polymorphisms in GSTP1, GSTT1 and GSTM1. A significantly lower BER rate was associated with the homozygous GSTT1 deletion in all asbestos site subjects and in the corresponding reference group. Multifactorial analysis revealed effects of sex and exposure in GSTP1 Ile/Val heterozygotes but not in Ile/Ile homozygotes. These variants affected also SBs levels, mainly by interactions of GSTP1 genotype with exposure, with sex, and with smoking habit; and by an interaction between sex and smoking. Our results show that GST polymorphisms and GST activity can apparently influence DNA stability and repair of oxidised bases, suggesting a potential new role for these

Are glutathione S-transferase polymorphisms (GSTM1, GSTT1) associated with primary open angle glaucoma? A meta-analysis.

Science.gov (United States)

Lu, Yan; Shi, Yuhua; Yin, Jie; Huang, Zhenping

2013-09-15

Glutathione S-transferase (GST) variants have been considered as risk factors for the pathogenesis of primary open angle glaucoma (POAG). However, the results have been inconsistent. In this study, we performed a meta-analysis to assess the association between GSTM1 and GSTT1 null genotypes and the risk for POAG. Published literature from PubMed and EMBASE databases was retrieved. All studies evaluating the association between GSTM1/GSTT1 variants and POAG were included. Pooled odds ratio (OR) and 95% confidence interval (CI) were calculated using fixed- or random-effects model. 14 studies (1711 POAG cases and 1537 controls) were included in the meta-analysis of GSTM1 genotypes and 10 studies (1306 POAG cases and 1114 controls) were included in the meta-analysis of GSTT1 genotypes. The overall result showed that the association between GSTM1 and GSTT1 null genotypes and risk for POAG was not statistically significant (GSTM1: OR=1.19, 95% CI=0.82-1.73, p=0.361; GSTT1: OR=1.26, 95% CI=0.77-2.06, p=0.365). The results by ethnicity showed that the association between the GSTM1 null genotype and risk for POAG is statistically significant in East Asians (OR=1.41, 95% CI=1.04-1.90, p=0.026), but not in Caucasians (OR=1.13, 95% CI=0.69-1.84, p=0.638) and Latin-American (OR=1.09, 95% CI=0.62-1.92, p=0.767). In addition, there was no significant association of GSTT1 null genotype with risk for POAG in either ethnic population. The present meta-analysis suggested that there might be a significant association of GSTM1 null genotype with POAG risk in East Asians. © 2013 Elsevier B.V. All rights reserved.

Blocking S1P interaction with S1P{sub 1} receptor by a novel competitive S1P{sub 1}-selective antagonist inhibits angiogenesis

Energy Technology Data Exchange (ETDEWEB)

Fujii, Yasuyuki, E-mail: y.fujii@po.rd.taisho.co.jp [Department of Molecular Function and Pharmacology Laboratories, Taisho Pharmaceutical Co. Ltd., 1-403 Saitama, Saitama 331-9530 (Japan); Ueda, Yasuji; Ohtake, Hidenori; Ono, Naoya; Takayama, Tetsuo; Nakazawa, Kiyoshi [Department of Molecular Function and Pharmacology Laboratories, Taisho Pharmaceutical Co. Ltd., 1-403 Saitama, Saitama 331-9530 (Japan); Igarashi, Yasuyuki [Laboratory of Biomembrane and Biofunctional Chemistry, Hokkaido University, Sapporo, Hokkaido 060-0812 (Japan); Goitsuka, Ryo [Division of Development and Aging, Research Institute for Biological Sciences, Tokyo University of Science, Noda, Chiba 278-0022 (Japan)

2012-03-23

Highlights: Black-Right-Pointing-Pointer The effect of a newly developed S1P{sub 1}-selective antagonist on angiogenic responses. Black-Right-Pointing-Pointer S1P{sub 1} is a critical component of VEGF-related angiogenic responses. Black-Right-Pointing-Pointer S1P{sub 1}-selective antagonist showed in vitro activity to inhibit angiogenesis. Black-Right-Pointing-Pointer S1P{sub 1}-selective antagonist showed in vivo activity to inhibit angiogenesis. Black-Right-Pointing-Pointer The efficacy of S1P{sub 1}-selective antagonist for anti-cancer therapies. -- Abstract: Sphingosine 1-phosphate receptor type 1 (S1P{sub 1}) was shown to be essential for vascular maturation during embryonic development and it has been demonstrated that substantial crosstalk exists between S1P{sub 1} and other pro-angiogenic growth factors, such as vascular endothelial growth factor (VEGF) and basic fibroblast growth factor. We developed a novel S1P{sub 1}-selective antagonist, TASP0277308, which is structurally unrelated to S1P as well as previously described S1P{sub 1} antagonists. TASP0277308 inhibited S1P- as well as VEGF-induced cellular responses, including migration and proliferation of human umbilical vein endothelial cells. Furthermore, TASP0277308 effectively blocked a VEGF-induced tube formation in vitro and significantly suppressed tumor cell-induced angiogenesis in vivo. These findings revealed that S1P{sub 1} is a critical component of VEGF-related angiogenic responses and also provide evidence for the efficacy of TASP0277308 for anti-cancer therapies.

β(1,3-glucanosyl-transferase activity is essential for cell wall integrity and viability of Schizosaccharomyces pombe.

Directory of Open Access Journals (Sweden)

María de Medina-Redondo

Full Text Available BACKGROUND: The formation of the cell wall in Schizosaccharomyces pombe requires the coordinated activity of enzymes involved in the biosynthesis and modification of β-glucans. The β(1,3-glucan synthase complex synthesizes linear β(1,3-glucans, which remain unorganized until they are cross-linked to other β(1,3-glucans and other cell wall components. Transferases of the GH72 family play important roles in cell wall assembly and its rearrangement in Saccharomyces cerevisiae and Aspergillus fumigatus. Four genes encoding β(1,3-glucanosyl-transferases -gas1(+, gas2(+, gas4(+ and gas5(+- are present in S. pombe, although their function has not been analyzed. METHODOLOGY/PRINCIPAL FINDINGS: Here, we report the characterization of the catalytic activity of gas1p, gas2p and gas5p together with studies directed to understand their function during vegetative growth. From the functional point of view, gas1p is essential for cell integrity and viability during vegetative growth, since gas1Δ mutants can only grow in osmotically supported media, while gas2p and gas5p play a minor role in cell wall construction. From the biochemical point of view, all of them display β(1,3-glucanosyl-transferase activity, although they differ in their specificity for substrate length, cleavage point and product size. In light of all the above, together with the differences in expression profiles during the life cycle, the S. pombe GH72 proteins may accomplish complementary, non-overlapping functions in fission yeast. CONCLUSIONS/SIGNIFICANCE: We conclude that β(1,3-glucanosyl-transferase activity is essential for viability in fission yeast, being required to maintain cell integrity during vegetative growth.

Contribution of Arginine 13 to the Catalytic Activity of Human Class Pi Glutathione Transferase P1-1

International Nuclear Information System (INIS)

Kong, Ji Na; Jo, Dong Hyeon; Do, Hyun Dong; Lee, Jin Ju; Kong, Kwang Hoon

2010-01-01

Arg13 is a conserved active-site residue in all known Pi class glutathione S-transferases (GSTs) and in most Alpha class GSTs. To evaluate its contribution to substrate binding and catalysis of this residue, three mutants (R13A, R13K, and R13L) were expressed in Escherichia coli and purified by GSH affinity chromatography. The substitutions of Arg13 significantly affected GSH-conjugation activity, while scarcely affecting glutathione peroxidase or steroid isomerase activities. Mutation of Arg13 into Ala largely reduced the GSH-conjugation activity by approximately 85 - 95%, whereas substitutions by Lys and Leu barely affected activity. These results suggest that, in the GSH-conjugation activity of hGST P1-1, the contribution of Arg13 toward catalytic activity is highly dependent on substrate specificities and the size of the side chain at position 13. From the kinetic parameters, introduction of larger side chains at position 13 results in stronger affinity (Leu > Lys, Arg > Ala) towards GSH. The substitutions of Arg13 with alanine and leucine significantly affected k cat , whereas substitution with Lys was similar to that of the wild type, indicating the significance of a positively charged residue at position 13. From the plots of log (k cat /K m CDNB ) against pH, the pK a values of the thiol group of GSH bound in R13A, R13K, and R13L were estimated to be 1.8, 1.4, and 1.8 pK units higher than the pK a value of the wildtype enzyme, demonstrating the contribution of the Arg13 guanidinium group to the electrostatic field in the active site. From these results, we suggest that contribution of Arg13 in substrate binding is highly dependent on the nature of the electrophilic substrates, while in the catalytic mechanism, it stabilizes the GSH thiolate through hydrogen bonding

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

Science.gov (United States)

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.

Glutathione S-Transferase M1 and T1 Null Genotype Frequency ...

Indian Academy of Sciences (India)

Bluebird

2017-10-25

Oct 25, 2017 ... A comparative analysis with different tribal as well as world ..... T1 and P1) gene polymorphisms with type 2 diabetes mellitus in north .... Houlston R. S. 2000 CYP1A1 polymorphisms and lung cancer risk: a meta-analysis.

Role of household exposure, dietary habits and glutathione S-Transferases M1, T1 polymorphisms in susceptibility to lung cancer among women in Mizoram India.

Science.gov (United States)

Phukan, Rup Kumar; Saikia, Bhaskar Jyoti; Borah, Prasanta Kumar; Zomawia, Eric; Sekhon, Gaganpreet Singh; Mahanta, Jagadish

2014-01-01

A case-control study was conducted to evaluate the effect of household exposure, dietary habits, smoking and Glutathione S-Transferases M1, T1 polymorphisms on lung cancer among women in Mizoram, India. We selected 230 newly diagnosed primary lung cases and 460 controls from women in Mizoram. Multivariate logistic regression analysis was performed to estimate adjusted odds ratio (OR). Exposure of cooking oil fumes (pkitchen inside living room (p=0.001), improper ventilated house (p=0.003), roasting of soda in kitchen (p=0.001), current smokers of tobacco (p=0.043), intake of smoked fish (p=0.006), smoked meat (p=0.001), Soda (poil emission and wood smoke, intake of smoked meat, smoked fish and soda (an alkali preparation used as food additives in Mizoram) and tobacco consumption for increase risk of lung cancer among Women in Mizoram.

Quasimolecular emission near the Xe(5p 56s 1,3 P 1 - 5p 6 1 S 0) and Kr (4p 55s 1,3 P 1 - 4p 6 1 S 0) resonance lines induced by collisions with He atoms

Science.gov (United States)

Alekseeva, O. S.; Devdariani, A. Z.; Grigorian, G. M.; Lednev, M. G.; Zagrebin, A. L.

2017-02-01

This study is devoted to the theoretical investigation of the quasimolecular emission of Xe*-He and Kr*-He collision pairs near the Xe (5p 56s 1,3 P 1 - 5p 6 1 S 0) and Kr (4p 55s 1,3 P 1 - 4p 6 1 S 0) resonance atomic lines. The potential curves of the quasimolecules Xe(5p 56s) + He and Kr(4p 55s) + He have been obtained with the use of the effective Hamiltonian and pseudopotential methods. Based on these potential curves the processes of quasimolecular emission of Xe*+He and Kr*+He mixtures have been considered and the spectral distributions I(ħΔω) of photons emitted have been obtained in the framework of quasistatic approximation.

Cyclopentenone prostaglandins as potential inducers of phase II detoxification enzymes. 15-deoxy-delta(12,14)-prostaglandin j2-induced expression of glutathione S-transferases.

Science.gov (United States)

Kawamoto, Y; Nakamura, Y; Naito, Y; Torii, Y; Kumagai, T; Osawa, T; Ohigashi, H; Satoh, K; Imagawa, M; Uchida, K

2000-04-14

Exposure of cells to a wide variety of chemoprotective compounds confers resistance to a broad set of carcinogens. For a subset of the chemoprotective compounds, protection is generated by an increase in the abundance of protective enzymes, such as glutathione S-transferases (GSTs). In the present study, we developed a cell culture system that potently responds to phenolic antioxidants and found that antitumor prostaglandins (PGs) are potential inducers of GSTs. We screened primary hepatocytes and multiple cell lines for inducing GST activity upon incubation with the phenolic antioxidant (tert-butylhydroquinone) and found that rat liver epithelial RL34 cells most potently responded. Based on an extensive screening of diverse chemical agents on the induction of GST activity in RL34 cells, the J2 series of PGs, 15-deoxy-Delta(12,14)-prostaglandin J2 (15-deoxy-Delta(12,14)-PGJ2) in particular, were found to be potential inducers of GST. Enhanced gene expression of Class pi GST isozyme (GSTP1) by 15-deoxy-Delta(12,14)-PGJ2 was evident as a drastic elevation of the mRNA level. Hence, we examined the molecular mechanism underlying the 15-deoxy-Delta(12, 14)-PGJ2-induced GSTP1 gene expression. From functional analysis of various deletion mutant genes, we found that the 15-deoxy-Delta(12, 14)-PGJ2 reponse element was localized in a region containing a GSTP1 enhancer I (GPEI) that consists of two imperfect phorbol 12-O-tetradecanoylphorbol-13-acetate response elements. When the GPEI was combined with the minimum GSTP1 promoter, the element indeed showed an enhancer activity in response to 15-deoxy-Delta(12, 14)-PGJ2. Point mutations of either of the two imperfect 12-O-tetradecanoylphorbol-13-acetate response elements in GPEI completely abolished the enhancer activity. Gel mobility shift assays demonstrated that 15-deoxy-Delta(12,14)-PGJ2 specifically stimulated the binding of nuclear proteins including the transcription factor c-Jun, but not Nrf2, to GPEI. These results

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

Science.gov (United States)

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 (Pvitiligo (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.

Downregulation of sphingosine 1-phosphate (S1P) receptor 1 by dexamethasone inhibits S1P-induced mesangial cell migration.

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Koch, Alexander; Jäger, Manuel; Völzke, Anja; Grammatikos, Georgios; Zu Heringdorf, Dagmar Meyer; Huwiler, Andrea; Pfeilschifter, Josef

2015-06-01

Sphingosine 1-phosphate (S1P) is generated by sphingosine kinase (SK)-1 and -2 and acts mainly as an extracellular ligand at five specific receptors, denoted S1P1-5. After activation, S1P receptors regulate important processes in the progression of renal diseases, such as mesangial cell migration and survival. Previously, we showed that dexamethasone enhances SK-1 activity and S1P formation, which protected mesangial cells from stress-induced apoptosis. Here we demonstrate that dexamethasone treatment lowered S1P1 mRNA and protein expression levels in rat mesangial cells. This effect was abolished in the presence of the glucocorticoid receptor antagonist RU-486. In addition, in vivo studies showed that dexamethasone downregulated S1P1 expression in glomeruli isolated from mice treated with dexamethasone (10 mg/kg body weight). Functionally, we identified S1P1 as a key player mediating S1P-induced mesangial cell migration. We show that dexamethasone treatment significantly lowered S1P-induced migration of mesangial cells, which was again reversed in the presence of RU-486. In summary, we suggest that dexamethasone inhibits S1P-induced mesangial cell migration via downregulation of S1P1. Overall, these results demonstrate that dexamethasone has functional important effects on sphingolipid metabolism and action in renal mesangial cells.

Intracellular S1P generation is essential for S1P-induced motility of human lung endothelial cells: role of sphingosine kinase 1 and S1P lyase.

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Evgeny V Berdyshev

Full Text Available BACKGROUND: Earlier we have shown that extracellular sphingosine-1-phosphate (S1P induces migration of human pulmonary artery endothelial cells (HPAECs through the activation of S1P(1 receptor, PKCε, and PLD2-PKCζ-Rac1 signaling cascade. As endothelial cells generate intracellular S1P, here we have investigated the role of sphingosine kinases (SphKs and S1P lyase (S1PL, that regulate intracellular S1P accumulation, in HPAEC motility. METHODOLOGY/PRINCIPAL FINDINGS: Inhibition of SphK activity with a SphK inhibitor 2-(p-Hydroxyanilino-4-(p-Chlorophenyl Thiazole or down-regulation of Sphk1, but not SphK2, with siRNA decreased S1P(int, and attenuated S1P(ext or serum-induced motility of HPAECs. On the contrary, inhibition of S1PL with 4-deoxypyridoxine or knockdown of S1PL with siRNA increased S1P(int and potentiated motility of HPAECs to S1P(ext or serum. S1P(ext mediates cell motility through activation of Rac1 and IQGAP1 signal transduction in HPAECs. Silencing of SphK1 by siRNA attenuated Rac1 and IQGAP1 translocation to the cell periphery; however, knockdown of S1PL with siRNA or 4-deoxypyridoxine augmented activated Rac1 and stimulated Rac1 and IQGAP1 translocation to cell periphery. The increased cell motility mediated by down-regulation was S1PL was pertussis toxin sensitive suggesting "inside-out" signaling of intracellularly generated S1P. Although S1P did not accumulate significantly in media under basal or S1PL knockdown conditions, addition of sodium vanadate increased S1P levels in the medium and inside the cells most likely by blocking phosphatases including lipid phosphate phosphatases (LPPs. Furthermore, addition of anti-S1P mAb to the incubation medium blocked S1P(ext or 4-deoxypyridoxine-dependent endothelial cell motility. CONCLUSIONS/SIGNIFICANCE: These results suggest S1P(ext mediated endothelial cell motility is dependent on intracellular S1P production, which is regulated, in part, by SphK1 and S1PL.

Genetic polymorphisms of glutathione-s-transferase M1 and T1 genes with risk of diabetic retinopathy in Iranian population

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Elham Moasser

2014-05-01

Full Text Available Objective(s:To the best of our knowledge, this is the first report on the contributions of GST genetic variants to the risk of diabetic retinopathy in an Iranian population. Therefore, the objective of this study was to determine whether sequence variation in glutathione S-transferase gene (GSTM1 and GSTT1 is associated with development of diabetic retinopathy in type 2 diabetes mellitus (T2DM Iranian patients. Materials and Methods: A total of 605 subjects were investigated in this case-control study; Study groups consisted of 201 patients with diabetic retinopathy (DR, 203 subjects with no clinically significant signs of DR and a group of 201 cases of healthy volunteers with no clinical evidence of diabetes mellitus or any other diseases. The GSTM1 and GSTT1 were genotyped by multiplex-polymerase chain reaction (multiplex-PCR analysis in all 404 T2DM patients and 201 healthy individuals served as control. Results: Increased odds ratio showed that GSTM1-null genotype had a moderately higher occurrence in T2DM patients (OR=1.43, 95% CI=1.01–2.04; P=0.03 than in healthy individuals. However, the frequency of GSTT1 genotype (OR=1.41; 95% CI=0.92-2.18; P=0.09 was not significantly different comparing both groups. Although, regression analysis in T2DM patients showed that GSTM1 and GSTT1 genotypes are not associated with T2DM retinopathy development. Conclusion: Our findings suggest that GSTM1 and GSTT1 genotypes might not be involved in the pathogenesis of type 2 diabetes mellitus retinopathy in the Southern Iranian population. However, further investigations are needed to confirm these results in other larger populations.

Arsenic-related skin lesions and glutathione S-transferase P1 A1578G (lle105Val) polymorphism in two ethnic clans exposed to indoor combustion of high arsenic coal in one village

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Lin, G.F.; Du, H.; Chen, J.G.; Lu, H.C.; Guo, W.C.; Meng, H.; Zhang, T.B.; Zhang, X.J.; Lu, D.R.; Golka, K.; Shen, J.H. [Chinese Academy of Sciences, Shanghai (China)

2006-12-15

A total of 2402 patients with arsenic-related skin lesions, such as hyperkeratosis, hyperpigmentation or hypopigmentation, or even skin cancer in a few villages in Southwest Guizhou Autonomous Prefecture, China represent a unique case of endemic arsenism related with indoor combustion of high arsenic coal. This study aimed to investigate the cluster of arsenism cases and the possible relevant factors including GSTP1 polymorphism in two clans of different ethnic origin living in one village for generations. Arsenism morbidity in Miao clan P was significantly lower than in the neighbouring Han clan G1 (5.9 vs. 32.7%, odds ratio (OR)=0.13, 95% confidence interval (CI): 0.06-0.27, P < 0.0001). No sex differences were confirmed inside both clans. Analyses of the environmental samples indicated that Miao clan P members were exposed to higher amounts of arsenic via inhalation and food ingestion. Hair and urine samples also proved a higher arsenic body burden in ethnic Miao individuals. No corresponding differences by sex were found. Higher frequencies of combined mutant genotype G/G1578 and A/G1578 (OR=4.72, 95% CI: 2.34-9.54, P < 0.0001) and of mutant allele G1578 (OR=3.22, 95% CI: 2.00-5.18, P < 0.0001) were detected in diagnosed arsenism patients than in non-diseased individuals. The Miao individuals showed a lower percentage of combined mutant genotypes (30.6 vs. 52.7%, OR=0.40, 95% CI: 0.19-0.84, P=0.015) as well as of mutant allele G1578 (OR=0.46, 95% CI: 0.24-0.88, P=0.017) than their Han neighbours. Conclusions Genetic predisposition influences dermal arsenism toxicity. The GSTP1 A1578G (IIe105Val) status might be a susceptibility factor for arsenic-related skin lesions.

Intracellular S1P Generation Is Essential for S1P-Induced Motility of Human Lung Endothelial Cells: Role of Sphingosine Kinase 1 and S1P Lyase

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Berdyshev, Evgeny V.; Gorshkova, Irina; Usatyuk, Peter; Kalari, Satish; Zhao, Yutong; Pyne, Nigel J.; Pyne, Susan; Sabbadini, Roger A.; Garcia, Joe G. N.; Natarajan, Viswanathan

2011-01-01

Background Earlier we have shown that extracellular sphingosine-1-phosphate (S1P) induces migration of human pulmonary artery endothelial cells (HPAECs) through the activation of S1P1 receptor, PKCε, and PLD2-PKCζ-Rac1 signaling cascade. As endothelial cells generate intracellular S1P, here we have investigated the role of sphingosine kinases (SphKs) and S1P lyase (S1PL), that regulate intracellular S1P accumulation, in HPAEC motility. Methodology/Principal Findings Inhibition of SphK activity with a SphK inhibitor 2-(p-Hydroxyanilino)-4-(p-Chlorophenyl) Thiazole or down-regulation of Sphk1, but not SphK2, with siRNA decreased S1Pint, and attenuated S1Pext or serum-induced motility of HPAECs. On the contrary, inhibition of S1PL with 4-deoxypyridoxine or knockdown of S1PL with siRNA increased S1Pint and potentiated motility of HPAECs to S1Pext or serum. S1Pext mediates cell motility through activation of Rac1 and IQGAP1 signal transduction in HPAECs. Silencing of SphK1 by siRNA attenuated Rac1 and IQGAP1 translocation to the cell periphery; however, knockdown of S1PL with siRNA or 4-deoxypyridoxine augmented activated Rac1 and stimulated Rac1 and IQGAP1 translocation to cell periphery. The increased cell motility mediated by down-regulation was S1PL was pertussis toxin sensitive suggesting “inside-out” signaling of intracellularly generated S1P. Although S1P did not accumulate significantly in media under basal or S1PL knockdown conditions, addition of sodium vanadate increased S1P levels in the medium and inside the cells most likely by blocking phosphatases including lipid phosphate phosphatases (LPPs). Furthermore, addition of anti-S1P mAb to the incubation medium blocked S1Pext or 4-deoxypyridoxine-dependent endothelial cell motility. Conclusions/Significance These results suggest S1Pext mediated endothelial cell motility is dependent on intracellular S1P production, which is regulated, in part, by SphK1 and S1PL. PMID:21304987

Sphingosine kinase 1/sphingosine-1-phosphate (S1P)/S1P receptor axis is involved in ovarian cancer angiogenesis.

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Dai, Lan; Liu, Yixuan; Xie, Lei; Wu, Xia; Qiu, Lihua; Di, Wen

2017-09-26

Sphingosine kinase (SphK)/sphingosine-1-phosphate (S1P)/S1P receptor (S1PR) signaling pathway has been implicated in a variety of pathological processes of ovarian cancer. However, the function of this axis in ovarian cancer angiogenesis remains incompletely defined. Here we provided the first evidence that SphK1/S1P/S1PR 1/3 pathway played key roles in ovarian cancer angiogenesis. The expression level of SphK1, but not SphK2, was closely correlated with the microvascular density (MVD) of ovarian cancer tissue. In vitro , the angiogenic potential and angiogenic factor secretion of ovarian cancer cells could be attenuated by SphK1, but not SphK2, blockage and were restored by the addition of S1P. Moreover, in these cells, we found S1P stimulation induced the angiogenic factor secretion via S1PR 1 and S1PR 3 , but not S1PR 2 . Furthermore, inhibition of S1PR 1/3 , but not S1PR 2 , attenuated the angiogenic potential and angiogenic factor secretion of the cells. in vivo , blockage of SphK or S1PR 1/3 could attenuate ovarian cancer angiogenesis and inhibit angiogenic factor expression in mouse models. Collectively, the current study showed a novel role of SphK1/S1P/S1PR 1/3 axis within the ovarian cancer, suggesting a new target to block ovarian cancer angiogenesis.

Glutathione S-transferase genotype and p53 mutations in adenocarcinoma of the small intestine

DEFF Research Database (Denmark)

Pedersen, Lisbeth Nørum; Kaerlev, L; Stubbe Teglbjaerg, P

2003-01-01

Adenocarcinoma of the small intestine (ASI) is a rare disease of unknown aetiology. The glutathione S-transferase M1 (GSTM1) enzyme catalyses the detoxification of compounds involved in carcinogenesis of adenocarcinoma of the stomach, colon and lung, including constituents of tobacco smoke. We in...

Association between glutathione S-transferase M1 and T1 polymorphisms and colorectal cancer risk in patients from Kazakhstan.

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Zhunussova, Gulnur; Zhunusbekova, Benazir; Djansugurova, Leyla

2015-01-01

Colorectal cancer (CRC) is one of the most common malignancies worldwide and the incidence is increasing in developed as well as developing countries including Kazakhstan. Glutathione S-transferases (GSTs) are considered to be cancer susceptibility genes as they play a role in the detoxification of carcinogenic species. In this case-control study the influence of GSTM1 and GSTT1 polymorphisms on CRC risk in Kazakhstan population were evaluated. Blood samples were collected from patients diagnosed with rectal or colon cancer (300 individuals) as well as a control cohort of healthy volunteers (300 individuals), taking into account the age, gender, ethnicity, and smoking habits of the CRC patients. Deletion polymorphisms were genotyped employing a multiplex PCR amplification method. Association between polymorphisms and CRC susceptibility risk was calculated using multivariate analysis and logistic regression for odd ratio (OR). The homozygous GSTM1 null genotype was associated with significantly increased risk of CRC (OR = 2.01, 95% CI = 1.45-2.79, p = 0.0001) while the homozygous GSST1 null genotype was not associated with the risk of developing CRC (OR = 1.10, 95% CI = 0.78-1.55, p = 0.001), but the heterozygous genotype correlated with CRC susceptibility (OR = 1.98, 95% CI = 1.30-3.00, p = 0.001). Also, separate analyses of each of the main ethnic groups (Kazakh and Russian) showed a strong association of GSTM1 null genotype with CRC risk (for Kazakhs OR = 2.36, 95% CI = 1.35-4.10, p = 0.006 and for Russians OR = 1.84, 95% CI = 1.17-2.89, p = 0.003). The CRC risk of GSTM1 null genotype in smokers was considerably higher (OR = 3.37, 95% CI = 1.78-6.38, p = 0.0007). The combination of the GSTM1 and GSTT1 null genotypes in combined mixed population of Kazakhstan showed a trend to increasing the risk of developing CRC (OR = 1.60, 95% CI = 1.00-2.56), but it was not statistically significant. In conclusion, the results of this case-control study for sporadic cases of

Genetic variation in genes for the xenobiotic-metabolizing enzymes CYP1A1, EPHX1, GSTM1, GSTT1 and GSTP1 and susceptibility to colorectal cancer in Lynch syndrome

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Pande, Mala; Amos, Christopher I.; Osterwisch, Daniel R.; Chen, Jinyun; Lynch, Patrick M.; Broaddus, Russell; Frazier, Marsha L.

2011-01-01

Individuals with Lynch syndrome are predisposed to cancer due to an inherited DNA mismatch repair gene mutation. However, there is significant variability observed in disease expression, likely due to the influence of other environmental, lifestyle, or genetic factors. Polymorphisms in genes encoding xenobiotic-metabolizing enzymes may modify cancer risk by influencing the metabolism and clearance of potential carcinogens from the body. In this retrospective analysis, we examined key candidate gene polymorphisms in CYP1A1, EPHX1, GSTT1, GSTM1, and GSTP1 as modifiers of age at onset of colorectal cancer among 257 individuals with Lynch syndrome. We found that subjects heterozygous for CYP1A1 I462V (c.1384A>G) developed colorectal cancer 4 years earlier than those with the homozygous wild-type genotype (median ages 39 and 43 years, respectively; log-rank test P = 0.018). Furthermore, being heterozygous for the CYP1A1 polymorphisms, I462V and Msp1 (g.6235T>C), was associated with an increased risk for developing colorectal cancer [adjusted hazard ratio for AG relative to AA = 1.78, 95% CI = 1.16–2.74, P = 0.008; and hazard ratio for TC relative to TT = 1.53, 95% CI = 1.06–2.22, P = 0.02]. Since homozygous variants for both CYP1A1 polymorphisms were rare, risk estimates were imprecise. None of the other gene polymorphisms examined were associated with an earlier onset age for colorectal cancer. Our results suggest that the I462V and Msp1 polymorphisms in CYP1A1 may be an additional susceptibility factor for disease expression in Lynch syndrome since they modify the age of colorectal cancer onset by up to 4 years. PMID:18768509

Sphingosine-1-Phosphate (S1P) and S1P Signaling Pathway: Therapeutic Targets in Autoimmunity and Inflammation.

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Tsai, Hsing-Chuan; Han, May H

2016-07-01

Sphingosine-1-phosphate (S1P) and S1P receptors (S1PR) are ubiquitously expressed. S1P-S1PR signaling has been well characterized in immune trafficking and activation in innate and adaptive immune systems. However, the full extent of its involvement in the pathogenesis of autoimmune diseases is not well understood. FTY720 (fingolimod), a non-selective S1PR modulator, significantly decreased annualized relapse rates in relapsing-remitting multiple sclerosis (MS). FTY720, which primarily targets S1P receptor 1 as a functional antagonist, arrests lymphocyte egress from secondary lymphoid tissues and reduces neuroinflammation in the central nervous system (CNS). Recent studies suggest that FTY720 also decreases astrogliosis and promotes oligodendrocyte differentiation within the CNS and may have therapeutic benefit to prevent brain atrophy. Since S1P signaling is involved in multiple immune functions, therapies targeting S1P axis may be applicable to treat autoimmune diseases other than MS. Currently, over a dozen selective S1PR and S1P pathway modulators with potentially superior therapeutic efficacy and better side-effect profiles are in the pipeline of drug development. Furthermore, newly characterized molecules such as apolipoprotein M (ApoM) (S1P chaperon) and SPNS2 (S1P transporter) are also potential targets for treatment of autoimmune diseases. Finally, the application of therapies targeting S1P and S1P signaling pathways may be expanded to treat several other immune-mediated disorders (such as post-infectious diseases, post-stroke and post-stroke dementia) and inflammatory conditions beyond their application in primary autoimmune diseases.

Targeting Glutathione-S Transferase Enzymes in Musculoskeletal Sarcomas: A Promising Therapeutic Strategy

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Michela Pasello

2011-01-01

Full Text Available Recent studies have indicated that targeting glutathione-S-transferase (GST isoenzymes may be a promising novel strategy to improve the efficacy of conventional chemotherapy in the three most common musculoskeletal tumours: osteosarcoma, Ewing's sarcoma, and rhabdomyosarcoma. By using a panel of 15 drug-sensitive and drug-resistant human osteosarcoma, Ewing's sarcoma, and rhabdomyosarcoma cell lines, the efficay of the GST-targeting agent 6-(7-nitro-2,1,3-benzoxadiazol-4-ylthiohexanol (NBDHEX has been assessed and related to GST isoenzymes expression (namely GSTP1, GSTA1, GSTM1, and MGST. NBDHEX showed a relevant in vitro activity on all cell lines, including the drug-resistant ones and those with higher GSTs levels. The in vitro activity of NBDHEX was mostly related to cytostatic effects, with a less evident apoptotic induction. NBDHEX positively interacted with doxorubicin, vincristine, cisplatin but showed antagonistic effects with methotrexate. In vivo studies confirmed the cytostatic efficay of NBDHEX and its positive interaction with vincristine in Ewing's sarcoma cells, and also indicated a positive effect against the metastatisation of osteosarcoma cells. The whole body of evidence found in this study indicated that targeting GSTs in osteosarcoma, Ewing's sarcoma and rhabdomyosarcoma may be an interesting new therapeutic option, which can be considered for patients who are scarcely responsive to conventional regimens.

Hyperoxia-induced p47phox activation and ROS generation is mediated through S1P transporter Spns2, and S1P/S1P1&2 signaling axis in lung endothelium.

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Harijith, Anantha; Pendyala, Srikanth; Ebenezer, David L; Ha, Alison W; Fu, Panfeng; Wang, Yue-Ting; Ma, Ke; Toth, Peter T; Berdyshev, Evgeny V; Kanteti, Prasad; Natarajan, Viswanathan

2016-08-01

Hyperoxia-induced lung injury adversely affects ICU patients and neonates on ventilator assisted breathing. The underlying culprit appears to be reactive oxygen species (ROS)-induced lung damage. The major contributor of hyperoxia-induced ROS is activation of the multiprotein enzyme complex NADPH oxidase. Sphingosine-1-phosphate (S1P) signaling is known to be involved in hyperoxia-mediated ROS generation; however, the mechanism(s) of S1P-induced NADPH oxidase activation is unclear. Here, we investigated various steps in the S1P signaling pathway mediating ROS production in response to hyperoxia in lung endothelium. Of the two closely related sphingosine kinases (SphKs)1 and 2, which synthesize S1P from sphingosine, only Sphk1(-/-) mice conferred protection against hyperoxia-induced lung injury. S1P is metabolized predominantly by S1P lyase and partial deletion of Sgpl1 (Sgpl1(+/-)) in mice accentuated lung injury. Hyperoxia stimulated S1P accumulation in human lung microvascular endothelial cells (HLMVECs), and downregulation of S1P transporter spinster homolog 2 (Spns2) or S1P receptors S1P1&2, but not S1P3, using specific siRNA attenuated hyperoxia-induced p47(phox) translocation to cell periphery and ROS generation in HLMVECs. These results suggest a role for Spns2 and S1P1&2 in hyperoxia-mediated ROS generation. In addition, p47(phox) (phox:phagocyte oxidase) activation and ROS generation was also reduced by PF543, a specific SphK1 inhibitor in HLMVECs. Our data indicate a novel role for Spns2 and S1P1&2 in the activation of p47(phox) and production of ROS involved in hyperoxia-mediated lung injury in neonatal and adult mice. Copyright © 2016 the American Physiological Society.

Association of Sphingosine-1-phosphate (S1P)/S1P Receptor-1 Pathway with Cell Proliferation and Survival in Canine Hemangiosarcoma.

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Rodriguez, A M; Graef, A J; LeVine, D N; Cohen, I R; Modiano, J F; Kim, J-H

2015-01-01

Sphingosine-1-phosphate (S1P) is a key biolipid signaling molecule that regulates cell growth and survival, but it has not been studied in tumors from dogs. S1P/S1P1 signaling will contribute to the progression of hemangiosarcoma (HSA). Thirteen spontaneous HSA tissues, 9 HSA cell lines, 8 nonmalignant tissues, including 6 splenic hematomas and 2 livers with vacuolar degeneration, and 1 endothelial cell line derived from a dog with splenic hematoma were used. This was a retrospective case series and in vitro study. Samples were obtained as part of medically necessary diagnostic procedures. Microarray, qRT-PCR, immunohistochemistry, and immunoblotting were performed to examine S1P1 expression. S1P concentrations were measured by high-performance liquid chromatography/mass spectrometry. S1P signaling was evaluated by intracellular Ca(2+) mobilization; proliferation and survival were evaluated using the MTS assay and Annexin V staining. Canine HSA cells expressed higher levels of S1P1 mRNA than nonmalignant endothelial cells. S1P1 protein was present in HSA tissues and cell lines. HSA cells appeared to produce low levels of S1P, but they selectively consumed S1P from the culture media. Exogenous S1P induced an increase in intracellular calcium as well as increased proliferation and viability of HSA cells. Prolonged treatment with FTY720, an inhibitor of S1P1 , decreased S1P1 protein expression and induced apoptosis of HSA cells. S1P/S1P1 signaling pathway functions to maintain HSA cell viability and proliferation. The data suggest that S1P1 or the S1P pathway in general could be targets for therapeutic intervention for dogs with HSA. Copyright © 2015 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.

Effects of curcumin on cytochrome P450 and glutathione S-transferase activities in rat liver.

NARCIS (Netherlands)

Oetari, S.; Sudibyo, M.; Commandeur, J.N.M.; Samhoedi, R.; Vermeulen, N.P.E.

1996-01-01

The stability of curcumin, as well as the interactions between curcumin and cytochrome P450s (P450s) and glutathione S-transferases (GSTs) in rat liver, were studied. Curcumin is relatively unstable in phosphate buffer at pH 7.4. The stability of curcumin was strongly improved by lowering the pH or

Interaction effects of long-term air pollution exposure and variants in the GSTP1, GSTT1 and GSTCD genes on risk of acute myocardial infarction and hypertension: a case-control study.

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Anna Levinsson

Full Text Available INTRODUCTION: Experimental and epidemiological studies have reported associations between air pollution exposure, in particular related to vehicle exhaust, and cardiovascular disease. A potential pathophysiological pathway is pollution-induced pulmonary oxidative stress, with secondary systemic inflammation. Genetic polymorphisms in genes implicated in oxidative stress, such as GSTP1, GSTT1 and GSTCD, may contribute to determining individual susceptibility to air pollution as a promoter of coronary vulnerability. AIMS: We aimed to investigate effects of long-term traffic-related air pollution exposure, as well as variants in GSTP1, GSTT1 and GSTCD, on risk of acute myocardial infarction (AMI and hypertension. In addition, we studied whether air pollution effects were modified by the investigated genetic variants. METHODS: Genotype data at 7 single nucleotide polymorphisms (SNPs in the GSTP1 gene, and one in each of the GSTT1 and GSTCD genes, as well as air pollution exposure estimates, were available for 119 AMI cases and 1310 randomly selected population controls. Population control individuals with systolic blood pressure ≥140 mmHg, diastolic blood pressure ≥90 mmHg or on daily antihypertensive medication were defined as hypertensive (n = 468. Individual air pollution exposure levels were modeled as annual means of NO₂ (marker of vehicle exhaust pollutants using central monitoring data and dispersion models, linking to participants' home addresses. RESULTS: Air pollution was significantly associated with risk of AMI: OR 1.78 (95%CI 1.04-3.03 per 10 µg/m³ of long-term NO₂ exposure. Three GSTP1 SNPs were significantly associated with hypertension. The effect of air pollution on risk of AMI varied by genotype strata, although the suggested interaction was not significant. We saw no obvious interaction between genetic variants in the GST genes and air pollution exposure for hypertension. CONCLUSION: Air pollution exposure entails an

Interaction effects of long-term air pollution exposure and variants in the GSTP1, GSTT1 and GSTCD genes on risk of acute myocardial infarction and hypertension: a case-control study.

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Levinsson, Anna; Olin, Anna-Carin; Modig, Lars; Dahgam, Santosh; Björck, Lena; Rosengren, Annika; Nyberg, Fredrik

2014-01-01

Experimental and epidemiological studies have reported associations between air pollution exposure, in particular related to vehicle exhaust, and cardiovascular disease. A potential pathophysiological pathway is pollution-induced pulmonary oxidative stress, with secondary systemic inflammation. Genetic polymorphisms in genes implicated in oxidative stress, such as GSTP1, GSTT1 and GSTCD, may contribute to determining individual susceptibility to air pollution as a promoter of coronary vulnerability. We aimed to investigate effects of long-term traffic-related air pollution exposure, as well as variants in GSTP1, GSTT1 and GSTCD, on risk of acute myocardial infarction (AMI) and hypertension. In addition, we studied whether air pollution effects were modified by the investigated genetic variants. Genotype data at 7 single nucleotide polymorphisms (SNPs) in the GSTP1 gene, and one in each of the GSTT1 and GSTCD genes, as well as air pollution exposure estimates, were available for 119 AMI cases and 1310 randomly selected population controls. Population control individuals with systolic blood pressure ≥140 mmHg, diastolic blood pressure ≥90 mmHg or on daily antihypertensive medication were defined as hypertensive (n = 468). Individual air pollution exposure levels were modeled as annual means of NO₂ (marker of vehicle exhaust pollutants) using central monitoring data and dispersion models, linking to participants' home addresses. Air pollution was significantly associated with risk of AMI: OR 1.78 (95%CI 1.04-3.03) per 10 µg/m³ of long-term NO₂ exposure. Three GSTP1 SNPs were significantly associated with hypertension. The effect of air pollution on risk of AMI varied by genotype strata, although the suggested interaction was not significant. We saw no obvious interaction between genetic variants in the GST genes and air pollution exposure for hypertension. Air pollution exposure entails an increased risk of AMI, and this risk differed over genotype strata

[Role and related mechanism of S1P/S1P1 signal pathway during post conditioning of hypertrophic cardiomyocytes].

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Bao, X H; Li, H X; Tao, J; Li, X M; Yang, Y N; Ma, Y T; Chen, B D

2016-05-24

To study the role and mechanism of sphingosine-1-phosphate (S1P)/ sphingosine-1-phosphate receptor 1(S1P1) signal pathway during post conditioning of hypertrophic cardiomyocytes. Neonatal rat cardiomyocytes were isolated and cultured, then stimulated by norepinephrine (NE) to induce cardiomyocytes hypertrophy. Using tri-gas incubator to create hypoxia and reoxygenation enviroment to mimic ischemia-reperfusion and postconditioning. Hypertrophic cardiomyoctyes were divided into five groups according to the presence or absence of various drugs and postconditiong and relevant signal pathways changes were detected: (1) IPost group (hypoxia+ postconditioning); (2) IPost+ S1P group (cells were pretreated with S1P (1 μmol/L) for 2 h before IPost); (3) IPost+ W-146+ S1P group (cells in IPost+ W-146+ S1P group were pretreated with S1P1 inhibitor W-146 (0.4 μmol/L) for 20 min); (4) IPost+ PD98059+ S1P group (cells in IPost+ S1P group were pretreated with MAPK antagonist PD98059 (125 μmol/L) for 20 min); (5) IPost+ LY-294002+ S1P group (cells in IPost+ S1P group were pretreated with PI3K antagonist LY294002 (0.1 μmol/L) for 20 min). Apoptosis was detected by flow cytometry and protein expression of relevant signal pathways were detected by Western blot. (1)Apoptosis rate was significantly increased in hypoxia/reoxygenation (27.90±4.49)% group compared with normal control group (7.97±2.18)%, which could be significantly reduced in IPost group (15.90±1.77)% (all PS1P and IPost+ S1P+ LY-294002 groups than in IPost and IPost+ S1P+ W-146 and IPost+ S1P+ PD98059 group (all PS1P and IPost+ S1P+ LY-294002 group than in IPost and IPost+ S1P+ W-146 group and IPost+ S1P+ PD98059 group (all PS1P+ W-146 and IPost+ S1P+ PD98059 groups. p-ERK1/2 and p-Akt levels in IPost+ S1P+ W-146 group and IPost+ S1P+ PD98059 were similar as in IPost group. S1P can play protective role on NE induced cardiomyocytes hypertrophy during post conditioning through downregulating caspase-3 expression and

Sphingosine-1-Phosphate (S1P) Lyase Inhibition Causes Increased Cardiac S1P Levels and Bradycardia in Rats.

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Harris, Christopher M; Mittelstadt, Scott; Banfor, Patricia; Bousquet, Peter; Duignan, David B; Gintant, Gary; Hart, Michelle; Kim, Youngjae; Segreti, Jason

2016-10-01

Inhibition of the sphingosine-1-phosphate (S1P)-catabolizing enzyme S1P lyase (S1PL) elevates the native ligand of S1P receptors and provides an alternative mechanism for immune suppression to synthetic S1P receptor agonists. S1PL inhibition is reported to preferentially elevate S1P in lymphoid organs. Tissue selectivity could potentially differentiate S1PL inhibitors from S1P receptor agonists, the use of which also results in bradycardia, atrioventricular block, and hypertension. But it is unknown if S1PL inhibition would also modulate cardiac S1P levels or cardiovascular function. The S1PL inhibitor 6-[(2R)-4-(4-benzyl-7-chlorophthalazin-1-yl)-2-methylpiperazin-1-yl]pyridine-3-carbonitrile was used to determine the relationship in rats between drug concentration, S1P levels in select tissues, and circulating lymphocytes. Repeated oral doses of the S1PL inhibitor fully depleted circulating lymphocytes after 3 to 4 days of treatment in rats. Full lymphopenia corresponded to increased levels of S1P of 100- to 1000-fold in lymph nodes, 3-fold in blood (but with no change in plasma), and 9-fold in cardiac tissue. Repeated oral dosing of the S1PL inhibitor in telemeterized, conscious rats resulted in significant bradycardia within 48 hours of drug treatment, comparable in magnitude to the bradycardia induced by 3 mg/kg fingolimod. These results suggest that S1PL inhibition modulates cardiac function and does not provide immune suppression with an improved cardiovascular safety profile over fingolimod in rats. Copyright © 2016 by The American Society for Pharmacology and Experimental Therapeutics.

Sphingosine 1-phosphate (S1P) suppresses the collagen-induced activation of human platelets via S1P4 receptor.

Science.gov (United States)

Onuma, Takashi; Tanabe, Kumiko; Kito, Yuko; Tsujimoto, Masanori; Uematsu, Kodai; Enomoto, Yukiko; Matsushima-Nishiwaki, Rie; Doi, Tomoaki; Nagase, Kiyoshi; Akamatsu, Shigeru; Tokuda, Haruhiko; Ogura, Shinji; Iwama, Toru; Kozawa, Osamu; Iida, Hiroki

2017-08-01

Sphingosine 1-phosphate (S1P) is as an extracellular factor that acts as a potent lipid mediator by binding to specific receptors, S1P receptors (S1PRs). However, the precise role of S1P in human platelets that express S1PRs has not yet been fully clarified. We previously reported that heat shock protein 27 (HSP27) is released from human platelets accompanied by its phosphorylation stimulated by collagen. In the present study, we investigated the effect of S1P on the collagen-induced platelet activation. S1P pretreatment markedly attenuated the collagen-induced aggregation. Co-stimulation with S1P and collagen suppressed collagen-induced platelet activation, but the effect was weaker than that of S1P-pretreatment. The collagen-stimulated secretion of platelet-derived growth factor (PDGF)-AB and the soluble CD40 ligand (sCD40L) release were significantly reduced by S1P. In addition, S1P suppressed the collagen-induced release of HSP27 as well as the phosphorylation of HSP27. S1P significantly suppressed the collagen-induced phosphorylation of p38 mitogen-activated protein kinase. S1P increased the levels of GTP-bound Gαi and GTP-bound Gα13 coupled to S1PPR1 and/or S1PR4. CYM50260, a selective S1PR4 agonist, but not SEW2871, a selective S1PR1 agonist, suppressed the collagen-stimulated platelet aggregation, PDGF-AB secretion and sCD40L release. In addition, CYM50260 reduced the release of phosphorylated-HSP27 by collagen as well as the phosphorylation of HSP27. The selective S1PR4 antagonist CYM50358, which failed to affect collagen-induced HSP27 phosphorylation, reversed the S1P-induced attenuation of HSP27 phosphorylation by collagen. These results strongly suggest that S1P inhibits the collagen-induced human platelet activation through S1PR4 but not S1PR1. Copyright © 2017 Elsevier Ltd. All rights reserved.

Glutathione S-transferase M1, T1 and P1 gene polymorphisms and ...

African Journals Online (AJOL)

Moyassar Ahmad Zaki

2014-04-18

Apr 18, 2014 ... (CIMT) was done using a b-mode ultrasound to detect peripheral atherosclerotic ..... Diagnosis and classification of · diabetes mellitus. .... Breast cancer and CYP1A1, GSTM1, and GSTT1 polymorphism: · evidence of a lack of ...

Regulation of human cerebro-microvascular endothelial baso-lateral adhesion and barrier function by S1P through dual involvement of S1P1 and S1P2 receptors.

Science.gov (United States)

Wiltshire, Rachael; Nelson, Vicky; Kho, Dan Ting; Angel, Catherine E; O'Carroll, Simon J; Graham, E Scott

2016-01-27

Herein we show that S1P rapidly and acutely reduces the focal adhesion strength and barrier tightness of brain endothelial cells. xCELLigence biosensor technology was used to measure focal adhesion, which was reduced by S1P acutely and this response was mediated through both S1P1 and S1P2 receptors. S1P increased secretion of several pro-inflammatory mediators from brain endothelial cells. However, the magnitude of this response was small in comparison to that mediated by TNFα or IL-1β. Furthermore, S1P did not significantly increase cell-surface expression of any key cell adhesion molecules involved in leukocyte recruitment, included ICAM-1 and VCAM-1. Finally, we reveal that S1P acutely and dynamically regulates microvascular endothelial barrier tightness in a manner consistent with regulated rapid opening followed by closing and strengthening of the barrier. We hypothesise that the role of the S1P receptors in this process is not to cause barrier dysfunction, but is related to controlled opening of the endothelial junctions. This was revealed using real-time measurement of barrier integrity using ECIS ZΘ TEER technology and endothelial viability using xCELLigence technology. Finally, we show that these responses do not occur simply though the pharmacology of a single S1P receptor but involves coordinated action of S1P1 and S1P2 receptors.

The interaction of glutathione S-transferase M1-null variants with tobacco smoke exposure and the development of childhood asthma

DEFF Research Database (Denmark)

Rogers, A J; Brasch-Andersen, C; Ionita-Laza, I

2009-01-01

BACKGROUND: The glutathione S-transferase M1 (GSTM1)-null variant is a common copy number variant associated with adverse pulmonary outcomes, including asthma and airflow obstruction, with evidence of important gene-by-environment interactions with exposures to oxidative stress. OBJECTIVE: To exp...

Sphingosine 1-phosphate (S1P)/S1P receptor 1 signaling regulates receptor activator of NF-κB ligand (RANKL) expression in rheumatoid arthritis

International Nuclear Information System (INIS)

Takeshita, Harunori; Kitano, Masayasu; Iwasaki, Tsuyoshi; Kitano, Sachie; Tsunemi, Sachi; Sato, Chieri; Sekiguchi, Masahiro; Azuma, Naoto; Miyazawa, Keiji; Hla, Timothy; Sano, Hajime

2012-01-01

Highlights: ► MH7A cells and CD4 + T cells expressed S1P1 and RANKL. ► S1P increased RANKL expression in MH7A cells and CD4 + T cells. ► The effect of S1P in MH7A cells was inhibited by specific Gi/Go inhibitors. -- Abstract: Sphingosine 1-phosphate (S1P)/S1P receptor 1 (S1P1) signaling plays an important role in synovial cell proliferation and inflammatory gene expression by rheumatoid arthritis (RA) synoviocytes. The purpose of this study is to clarify the role of S1P/S1P1 signaling in the expression of receptor activator of NF-κB ligand (RANKL) in RA synoviocytes and CD4 + T cells. We demonstrated MH7A cells, a human RA synovial cell line, and CD4 + T cells expressed S1P1 and RANKL. Surprisingly, S1P increased RANKL expression in MH7A cells and CD4 + T cells in a dose-dependent manner. Moreover, S1P enhanced RANKL expression induced by stimulation with TNF-α in MH7A cells and CD4 + T cells. These effects of S1P in MH7A cells were inhibited by pretreatment with PTX, a specific Gi/Go inhibitor. These findings suggest that S1P/S1P1 signaling may play an important role in RANKL expression by MH7A cells and CD4 + T cells. S1P/S1P1 signaling of RA synoviocytes is closely connected with synovial hyperplasia, inflammation, and RANKL-induced osteoclastogenesis in RA. Thus, regulation of S1P/S1P1 signaling may become a novel therapeutic target for RA.

Sphingosine 1-phosphate (S1P)/S1P receptor 1 signaling regulates receptor activator of NF-{kappa}B ligand (RANKL) expression in rheumatoid arthritis

Energy Technology Data Exchange (ETDEWEB)

Takeshita, Harunori [Division of Rheumatology, Department of Internal Medicine, Hyogo College of Medicine, 1-1 Mukogawa-cho, Nishinomiya, Hyogo 663-8501 (Japan); Kitano, Masayasu, E-mail: mkitano6@hyo-med.ac.jp [Division of Rheumatology, Department of Internal Medicine, Hyogo College of Medicine, 1-1 Mukogawa-cho, Nishinomiya, Hyogo 663-8501 (Japan); Iwasaki, Tsuyoshi [Department of Pharmacy, Hyogo University of Health Sciences, 1-3-6 Minatojima Kobe, Hyogo 650-8530 (Japan); Kitano, Sachie; Tsunemi, Sachi; Sato, Chieri; Sekiguchi, Masahiro; Azuma, Naoto [Division of Rheumatology, Department of Internal Medicine, Hyogo College of Medicine, 1-1 Mukogawa-cho, Nishinomiya, Hyogo 663-8501 (Japan); Miyazawa, Keiji [Discovery Research III, Research and Development, Kissei Pharmaceutical Company, 4365-1 Hodakakashiwara, Azumino, Nagano 399-8304 (Japan); Hla, Timothy [Center for Vascular Biology, Department of Pathology and Laboratory Medicine, Weill Medical College of Cornell University, 1300 York Avenue, Box 69, NY 10065 (United States); Sano, Hajime [Division of Rheumatology, Department of Internal Medicine, Hyogo College of Medicine, 1-1 Mukogawa-cho, Nishinomiya, Hyogo 663-8501 (Japan)

2012-03-09

Highlights: Black-Right-Pointing-Pointer MH7A cells and CD4{sup +} T cells expressed S1P1 and RANKL. Black-Right-Pointing-Pointer S1P increased RANKL expression in MH7A cells and CD4{sup +} T cells. Black-Right-Pointing-Pointer The effect of S1P in MH7A cells was inhibited by specific Gi/Go inhibitors. -- Abstract: Sphingosine 1-phosphate (S1P)/S1P receptor 1 (S1P1) signaling plays an important role in synovial cell proliferation and inflammatory gene expression by rheumatoid arthritis (RA) synoviocytes. The purpose of this study is to clarify the role of S1P/S1P1 signaling in the expression of receptor activator of NF-{kappa}B ligand (RANKL) in RA synoviocytes and CD4{sup +} T cells. We demonstrated MH7A cells, a human RA synovial cell line, and CD4{sup +} T cells expressed S1P1 and RANKL. Surprisingly, S1P increased RANKL expression in MH7A cells and CD4{sup +} T cells in a dose-dependent manner. Moreover, S1P enhanced RANKL expression induced by stimulation with TNF-{alpha} in MH7A cells and CD4{sup +} T cells. These effects of S1P in MH7A cells were inhibited by pretreatment with PTX, a specific Gi/Go inhibitor. These findings suggest that S1P/S1P1 signaling may play an important role in RANKL expression by MH7A cells and CD4{sup +} T cells. S1P/S1P1 signaling of RA synoviocytes is closely connected with synovial hyperplasia, inflammation, and RANKL-induced osteoclastogenesis in RA. Thus, regulation of S1P/S1P1 signaling may become a novel therapeutic target for RA.

Sphingosine kinase/sphingosine 1-phosphate (S1P)/S1P receptor axis is involved in liver fibrosis-associated angiogenesis.

Science.gov (United States)

Yang, Le; Yue, Shi; Yang, Lin; Liu, Xin; Han, Zhen; Zhang, Yuanyuan; Li, Liying

2013-07-01

Sphingosine kinase (SphK)/sphingosine 1-phosphate (S1P)/S1P receptor (S1PR) axis is involved in multiple biological processes, including liver fibrosis. Angiogenesis is an important pathophysiological process closely associated with liver fibrosis; however, the functional role of SphK/S1P/S1PR in this process remains incompletely defined. Bile duct ligation or carbon tetrachloride was used to induce liver fibrosis in mice. Human fibrotic samples were obtained from livers of patients undergoing liver transplantation. S1P levels in the liver were examined by HPLC. Expression of angiogenic markers, including angiopoietin 1, CD31, vascular cell adhesion molecule-1, and von Willebrand factor, was characterized by immunofluorescence, real-time RT-PCR, and Western blot in the fibrotic liver and primary mouse hepatic stellate cells (HSCs). SphK inhibitor (SKI) or S1PR antagonists were administered intraperitoneally in mice. S1P levels in the liver were closely correlated with mRNA expression of angiogenic markers. Ang1 is expressed in activated HSCs of the fibrotic liver and in primary HSCs. In HSCs, by using specific antagonists or siRNAs, we demonstrated S1P stimulation induced Ang1 expression via S1PR1 and S1PR3. In vivo, S1P reduction by SKI inhibited angiogenesis in fibrotic mice. Furthermore, S1PR1/3 antagonist significantly blocked upregulation of angiogenic markers in the injured liver, and attenuated the extent of liver fibrosis, while S1PR2 antagonist had no effect on angiogenesis, supporting the key role of S1PR1 and S1PR3 in angiogenesis underlying liver fibrosis process. SphK1/S1P/S1PR1/3 axis plays a crucial role in the angiogenic process required for fibrosis development, which may represent an effective therapeutic strategy for liver fibrosis. Copyright © 2013 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.

Variable effects of maternal and paternal-fetal contribution to the risk for preeclampsia combining GSTP1, eNOS, and LPL gene polymorphisms.

Science.gov (United States)

Pappa, Kalliopi I; Roubelakis, Maria; Vlachos, George; Marinopoulos, Spyros; Zissou, Antonia; Anagnou, Nicholas P; Antsaklis, Aris

2011-04-01

To evaluate the maternal, paternal, and fetal genotype contribution to preeclampsia. STUDY DESIGN, MATERIALS, AND METHODS: We combined the analysis of polymorphisms of the GSTP1, eNOS, and LPL genes - affecting biotransformation enzymes and endothelial function - in a cohort of 167 preeclamptic and normal control trios (mother, father, and child) comprising a total of 501 samples in the Greek population, never analyzed before by this approach. For the frequency of the GSTP1 Ile(105)/Val(105), the eNOS Glu298Asp and the LPL-93 polymorphisms, statistically significant differences were found between the two groups. However, the transmission rates of the parental alleles to neonates studied by the transmission disequilibrium test, disclosed no increased rate of transmission to preeclampsia children for the variant alleles of Val(105) GSTP1, 298Asp eNOS, and -93G LPL. These novel data, suggest that interaction of all three types of genotypes (mother, father and neonate), reveals no effects on the development of preeclampsia, but provide the impetus for further studies to decipher the individual contribution of each genetic parameter of preeclampsia.

Expression of P-glycoprotein, multidrug resistance-associated protein, glutathione-S-transferase pi and p53 in canine transmissible venereal tumor

Directory of Open Access Journals (Sweden)

Daniel G. Gerardi

2014-01-01

Full Text Available The overexpression of proteins P-glycoprotein (P-gp, multidrug resistance-associated protein (MRP1, mutant p53, and the enzyme glutathione-S-transferase (GSTpi are related to resistance to chemotherapy in neoplasms. This study evaluated the expression of these markers by immunohistochemistry in two groups of canine TVT, without history of prior chemotherapy (TVT1, n=9 and in TVTs presented unsatisfactory clinical response to vincristine sulfate (TVT2, n=5. The percentage of specimens positively stained for P-gp, MRP1, GSTpi and p53 were, respectively 88.8%, 0%, 44.5% and 22.2% in TVT1 and 80%, 0%, 80% and 0% in TVT2. In TVT1, one specimen presented positive expression for three markers and four specimens for two markers. In TVT2, three specimens expressed P-gp and GSTpi. In conclusion, the canine TVTs studied expressed the four markers evaluated, but just P-gp and GSTpi were significantly expressed, mainly at cytoplasm and cytoplasm and nuclei, respectively, either before chemotherapy as after vincristine sulfate exposure. Future studies are needed to demonstrate the function of these two markers in conferring multidrug resistance (MDR or predict the response to chemotherapy in canine TVT.

Benzene Uptake and Glutathione S-transferase T1 Status as Determinants of S-Phenylmercapturic Acid in Cigarette Smokers in the Multiethnic Cohort.

Directory of Open Access Journals (Sweden)

Christopher A Haiman

Full Text Available Research from the Multiethnic Cohort (MEC demonstrated that, for the same quantity of cigarette smoking, African Americans and Native Hawaiians have a higher lung cancer risk than Whites, while Latinos and Japanese Americans are less susceptible. We collected urine samples from 2,239 cigarette smokers from five different ethnic groups in the MEC and analyzed each sample for S-phenylmercapturic acid (SPMA, a specific biomarker of benzene uptake. African Americans had significantly higher (geometric mean [SE] 3.69 [0.2], p<0.005 SPMA/ml urine than Whites (2.67 [0.13] while Japanese Americans had significantly lower levels than Whites (1.65 [0.07], p<0.005. SPMA levels in Native Hawaiians and Latinos were not significantly different from those of Whites. We also conducted a genome-wide association study in search of genetic risk factors related to benzene exposure. The glutathione S-transferase T1 (GSTT1 deletion explained between 14.2-31.6% (p = 5.4x10-157 and the GSTM1 deletion explained between 0.2%-2.4% of the variance (p = 1.1x10-9 of SPMA levels in these populations. Ethnic differences in levels of SPMA remained strong even after controlling for the effects of these two deletions. These results demonstrate the powerful effect of GSTT1 status on SPMA levels in urine and show that uptake of benzene in African American, White, and Japanese American cigarette smokers is consistent with their lung cancer risk in the MEC. While benzene is not generally considered a cause of lung cancer, its metabolite SPMA could be a biomarker for other volatile lung carcinogens in cigarette smoke.

S1P lyase in thymic perivascular spaces promotes egress of mature thymocytes via up-regulation of S1P receptor 1.

Science.gov (United States)

Maeda, Yasuhiro; Yagi, Hideki; Takemoto, Kana; Utsumi, Hiroyuki; Fukunari, Atsushi; Sugahara, Kunio; Masuko, Takashi; Chiba, Kenji

2014-05-01

Sphingosine 1-phosphate (S1P) and S1P receptor 1 (S1P1) play an important role in the egress of mature CD4 or CD8 single-positive (SP) thymocytes from the thymus. Fingolimod hydrochloride (FTY720), an S1P1 functional antagonist, induced significant accumulation of CD62L(high)CD69(low) mature SP thymocytes in the thymic medulla. Immunohistochemical staining using anti-S1P1 antibody revealed that S1P1 is predominantly expressed on thymocytes in the thymic medulla and is strongly down-regulated even at 3h after FTY720 administration. 2-Acetyl-4-tetrahydroxybutylimidazole (THI), an S1P lyase inhibitor, also induced accumulation of mature SP thymocytes in the thymic medulla with an enlargement of the perivascular spaces (PVS). At 6h after THI administration, S1P1-expressing thymocytes reduced partially as if to form clusters and hardly existed in the proximity of CD31-expressing blood vessels in the thymic medulla, suggesting S1P lyase expression in the cells constructing thymic medullary PVS. To determine the cells expressing S1P lyase in the thymus, we newly established a mAb (YK19-2) specific for mouse S1P lyase. Immunohistochemical staining with YK19-2 revealed that S1P lyase is predominantly expressed in non-lymphoid thymic stromal cells in the thymic medulla. In the thymic medullary PVS, S1P lyase was expressed in ER-TR7-positive cells (reticular fibroblasts and pericytes) and CD31-positive vascular endothelial cells. Our findings suggest that S1P lyase expressed in the thymic medullary PVS keeps the tissue S1P concentration low around the vessels and promotes thymic egress via up-regulation of S1P1.

Role of sphingosine 1-phosphate (S1P and effects of fingolimod, an S1P receptor 1 functional antagonist in lymphocyte circulation and autoimmune diseases

Directory of Open Access Journals (Sweden)

Kenji Chiba

2014-11-01

Full Text Available Sphingosine 1-phosphate (S1P, a multi-functional phospholipid mediator, is generated from sphingosine by sphingosine kinases and binds to five known G protein-coupled S1P receptors (S1P1, S1P2, S1P3, S1P4, and S1P5. It is widely accepted that S1P receptor 1 (S1P1 plays an essential role in lymphocyte egress from the secondary lymphoid organs (SLO and thymus, because lymphocyte egress from these organs to periphery is at extremely low levels in mice lacking lymphocytic S1P1. Fingolimod hydrochloride (FTY720 is a first-in-class, orally active S1P1 functional antagonist which was discovered by chemical modification of a natural product, myriocin. Since FTY720 has a structure closely related to sphingosine, the phosphorylated FTY720 (FTY720-P is converted by sphingosine kinases and binds 4 types of S1P receptors. FTY720-P strongly induces down-regulation of S1P1 by internalization and degradation of this receptor and acts as a functional antagonist at S1P1. Consequently, FTY720 inhibits S1P1-dependent lymphocyte egress from the SLO and thymus to reduce circulating lymphocytes including autoreactive Th17 cells, and is highly effective in experimental autoimmune encephalomyelitis (EAE, an animal model of multiple sclerosis (MS. In relapsing remitting MS patients, oral FTY720 shows a superior efficacy when compared to intramuscular interferon-β-1a. Based on these data, it is presumed that modulation of the S1P-S1P1 axis provides an effective therapy for autoimmune diseases including MS.

Mechanism of Gene Expression of Arabidopsis Glutathione S-Transferase, AtGST1, and AtGST11 in Response to Aluminum Stress1

Science.gov (United States)

Ezaki, Bunichi; Suzuki, Masakatsu; Motoda, Hirotoshi; Kawamura, Masako; Nakashima, Susumu; Matsumoto, Hideaki

2004-01-01

The gene expression of two Al-induced Arabidopsis glutathione S-transferase genes, AtGST1 and AtGST11, was analyzed to investigate the mechanism underlying the response to Al stress. An approximately 1-kb DNA fragment of the 5′-upstream region of each gene was fused to a β-glucuronidase (GUS) reporter gene (pAtGST1::GUS and pAtGST11::GUS) and introduced into Arabidopsis ecotype Landsberg erecta. The constructed transgenic lines showed a time-dependent gene expression to a different degree in the root and/or leaf by Al stress. The pAtGST1::GUS gene was induced after a short Al treatment (maximum expression after a 2-h exposure), while the pAtGST11::GUS gene was induced by a longer Al treatment (approximately 8 h for maximum expression). Since the gene expression was observed in the leaf when only the root was exposed to Al stress, a signaling system between the root and shoot was suggested in Al stress. A GUS staining experiment using an adult transgenic line carrying the pAtGST11::GUS gene supported this suggestion. Furthermore, Al treatment simultaneously with various Ca depleted conditions in root region enhanced the gene expression of the pAtGST11::GUS in the shoot region. This result suggested that the degree of Al toxicity in the root reflects the gene response of pAtGST11::GUS in the shoot via the deduced signaling system. Both transgenic lines also showed an increase of GUS activity after cold stress, heat stress, metal toxicity, and oxidative damages, suggesting a common induction mechanism in response to the tested stresses including Al stress. PMID:15047894

S1P in HDL promotes interaction between SR-BI and S1PR1 and activates S1PR1-mediated biological functions: calcium flux and S1PR1 internalization[S

Science.gov (United States)

Lee, Mi-Hye; Appleton, Kathryn M.; El-Shewy, Hesham M.; Sorci-Thomas, Mary G.; Thomas, Michael J.; Lopes-Virella, Maria F.; Luttrell, Louis M.; Hammad, Samar M.; Klein, Richard L.

2017-01-01

HDL normally transports about 50–70% of plasma sphingosine 1-phosphate (S1P), and the S1P in HDL reportedly mediates several HDL-associated biological effects and signaling pathways. The HDL receptor, SR-BI, as well as the cell surface receptors for S1P (S1PRs) may be involved partially and/or completely in these HDL-induced processes. Here we investigate the nature of the HDL-stimulated interaction between the HDL receptor, SR-BI, and S1PR1 using a protein-fragment complementation assay and confocal microscopy. In both primary rat aortic vascular smooth muscle cells and HEK293 cells, the S1P content in HDL particles increased intracellular calcium concentration, which was mediated by S1PR1. Mechanistic studies performed in HEK293 cells showed that incubation of cells with HDL led to an increase in the physical interaction between the SR-BI and S1PR1 receptors that mainly occurred on the plasma membrane. Model recombinant HDL (rHDL) particles formed in vitro with S1P incorporated into the particle initiated the internalization of S1PR1, whereas rHDL without supplemented S1P did not, suggesting that S1P transported in HDL can selectively activate S1PR1. In conclusion, these data suggest that S1P in HDL stimulates the transient interaction between SR-BI and S1PRs that can activate S1PRs and induce an elevation in intracellular calcium concentration. PMID:27881715

RESEARCH ARTICLE Glutathione S-Transferase P1 Gene ...

Indian Academy of Sciences (India)

Navya

2017-03-13

Mar 13, 2017 ... logistic regression analysis showed significant association of A/G (OR: 1.6, 95% CI: ... hypertension, diabetes mellitus and dyslipidemia are associated with ..... polymorphisms with the risk of prostate cancer: A meta-analysis.

Evaluation of the precision-cut liver and lung slice systems for the study of induction of CYP1, epoxide hydrolase and glutathione S-transferase activities.

Science.gov (United States)

Pushparajah, Daphnee S; Umachandran, Meera; Plant, Kathryn E; Plant, Nick; Ioannides, Costas

2007-02-28

The principal objective was to ascertain whether precision-cut tissue slices can be used to evaluate the potential of chemicals to induce CYP1, epoxide hydrolase and glutathione S-transferase activities, all being important enzymes involved in the metabolism of polycyclic aromatic hydrocarbons. Precision-cut rat liver and lung slices were incubated with a range of benzo[a]pyrene concentrations for various time periods. A rise in the O-deethylation of ethoxyresorufin was seen in both liver and lung slices exposed to benzo[a]pyrene, which was accompanied by increased CYP1A apoprotein levels. Pulmonary CYP1B1 apoprotein levels and hepatic mRNA levels were similarly enhanced. Elevated epoxide hydrolase and glutathione S-transferase activities were also observed in liver slices following incubation for 24h; similarly, a rise in apoprotein levels of both enzymes was evident, peak levels occurring at the same time point. When mRNA levels were monitored, a rise in the levels of both enzymes was seen as early as 4h after incubation, but maximum levels were attained at 24 h. In lung slices, induction of epoxide hydrolase by benzo[a]pyrene was observed after a 24-h incubation, and at a concentration of 1 microM; a rise in apoprotein levels was seen at this time point. Glutathione S-transferase activity was not inducible in lung slices by benzo[a]pyrene but a modest increase was observed in hepatic slices. Collectively, these studies confirmed CYP1A induction in rat liver slices and established that CYP1B1 expression, and epoxide hydrolase and glutathione S-transferase activities are inducible in precision-cut tissue slices.

Sphingosine-1-Phosphate (S1P) Signaling in Neural Progenitors.

Science.gov (United States)

Callihan, Phillip; Alqinyah, Mohammed; Hooks, Shelley B

2018-01-01

Sphingosine-1-phosphate (S1P) and its receptors are important in nervous system development. Reliable in vitro human model systems are needed to further define specific roles for S1P signaling in neural development. We have described S1P-regulated signaling, survival, and differentiation in a human embryonic stem cell-derived neuroepithelial progenitor cell line (hNP1) that expresses functional S1P receptors. These cells can be further differentiated to a neuronal cell type and therefore represent a good model system to study the role of S1P signaling in human neural development. The following sections describe in detail the culture and differentiation of hNP1 cells and two assays to measure S1P signaling in these cells.

S1P in HDL promotes interaction between SR-BI and S1PR1 and activates S1PR1-mediated biological functions: calcium flux and S1PR1 internalization.

Science.gov (United States)

Lee, Mi-Hye; Appleton, Kathryn M; El-Shewy, Hesham M; Sorci-Thomas, Mary G; Thomas, Michael J; Lopes-Virella, Maria F; Luttrell, Louis M; Hammad, Samar M; Klein, Richard L

2017-02-01

HDL normally transports about 50-70% of plasma sphingosine 1-phosphate (S1P), and the S1P in HDL reportedly mediates several HDL-associated biological effects and signaling pathways. The HDL receptor, SR-BI, as well as the cell surface receptors for S1P (S1PRs) may be involved partially and/or completely in these HDL-induced processes. Here we investigate the nature of the HDL-stimulated interaction between the HDL receptor, SR-BI, and S1PR1 using a protein-fragment complementation assay and confocal microscopy. In both primary rat aortic vascular smooth muscle cells and HEK293 cells, the S1P content in HDL particles increased intracellular calcium concentration, which was mediated by S1PR1. Mechanistic studies performed in HEK293 cells showed that incubation of cells with HDL led to an increase in the physical interaction between the SR-BI and S1PR1 receptors that mainly occurred on the plasma membrane. Model recombinant HDL (rHDL) particles formed in vitro with S1P incorporated into the particle initiated the internalization of S1PR1, whereas rHDL without supplemented S1P did not, suggesting that S1P transported in HDL can selectively activate S1PR1. In conclusion, these data suggest that S1P in HDL stimulates the transient interaction between SR-BI and S1PRs that can activate S1PRs and induce an elevation in intracellular calcium concentration.

Sphingosine 1-Phosphate (S1P) Receptors 1 and 2 Coordinately Induce Mesenchymal Cell Migration through S1P Activation of Complementary Kinase Pathways*

Science.gov (United States)

Quint, Patrick; Ruan, Ming; Pederson, Larry; Kassem, Moustapha; Westendorf, Jennifer J.; Khosla, Sundeep; Oursler, Merry Jo

2013-01-01

Normal bone turnover requires tight coupling of bone resorption and bone formation to preserve bone quantity and structure. With aging and during several pathological conditions, this coupling breaks down, leading to either net bone loss or excess bone formation. To preserve or restore normal bone metabolism, it is crucial to determine the mechanisms by which osteoclasts and osteoblast precursors interact and contribute to coupling. We showed that osteoclasts produce the chemokine sphingosine 1-phosphate (S1P), which stimulates osteoblast migration. Thus, osteoclast-derived S1P may recruit osteoblasts to sites of bone resorption as an initial step in replacing lost bone. In this study we investigated the mechanisms by which S1P stimulates mesenchymal (skeletal) cell chemotaxis. S1P treatment of mesenchymal (skeletal) cells activated RhoA GTPase, but this small G protein did not contribute to migration. Rather, two S1P receptors, S1PR1 and S1PR2, coordinately promoted migration through activation of the JAK/STAT3 and FAK/PI3K/AKT signaling pathways, respectively. These data demonstrate that the chemokine S1P couples bone formation to bone resorption through activation of kinase signaling pathways. PMID:23300082

Glutathione S-transferase P1 gene polymorphisms and susceptibility ...

Indian Academy of Sciences (India)

M. A. Bhat

2017-11-28

Nov 28, 2017 ... Binary logistic regression analysis showed significant association of A/G (odds ratio (OR): 1.6, 95% CI: 1.08–2.49, ... diet, advanced age, smoking, hypertension, diabetes mel- ..... risk of prostate cancer: A meta-analysis.

PPARγ agonists upregulate sphingosine 1-phosphate (S1P) receptor 1 expression, which in turn reduces S1P-induced [Ca(2+)]i increases in renal mesangial cells.

Science.gov (United States)

Koch, Alexander; Völzke, Anja; Puff, Bianca; Blankenbach, Kira; Meyer Zu Heringdorf, Dagmar; Huwiler, Andrea; Pfeilschifter, Josef

2013-11-01

We previously identified peroxisome proliferator-activated receptor gamma (PPARγ) agonists (thiazolidinediones, TZDs) as modulators of the sphingolipid metabolism in renal mesangial cells. TZDs upregulated sphingosine kinase 1 (SK-1) and increased the formation of intracellular sphingosine 1-phosphate (S1P), which in turn reduced the expression of pro-fibrotic connective tissue growth factor. Since S1P also acts as extracellular ligand at specific S1P receptors (S1PR, S1P1-5), we investigated here the effect of TZDs on S1PR expression in mesangial cells and evaluated the functional consequences by measuring S1P-induced increases in intracellular free Ca(2+) concentration ([Ca(2+)]i). Treatment with two different TZDs, troglitazone and rosiglitazone, enhanced S1P1 mRNA and protein expression in rat mesangial cells, whereas S1P2-5 expression levels were not altered. Upregulation of S1P1 mRNA upon TZD treatment was also detected in human mesangial cells and mouse glomeruli. PPARγ antagonism and promoter studies revealed that the TZD-dependent S1P1 mRNA induction involved a functional PPAR response element in the S1P1 promoter. Pharmacological approaches disclosed that S1P-induced [Ca(2+)]i increases in rat mesangial cells were predominantly mediated by S1P2 and S1P3. Interestingly, the transcriptional upregulation of S1P1 by TZDs resulted in a reduction of S1P-induced [Ca(2+)]i increases, which was reversed by the S1P1/3 antagonist VPC-23019, the protein kinase C (PKC) inhibitor PKC-412, and by S1P1 siRNA. These data suggest that PPARγ-dependent upregulation of S1P1 leads to an inhibition of S1P-induced Ca(2+) signaling in a PKC-dependent manner. Overall, these results reveal that TZDs not only modulate intracellular S1P levels but also regulate S1PR signaling by increasing S1P1 expression in mesangial cells. © 2013.

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

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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 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). 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.

Smad3 deficiency leads to mandibular condyle degradation via the sphingosine 1-phosphate (S1P)/S1P3 signaling axis.

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Mori, Hiroki; Izawa, Takashi; Tanaka, Eiji

2015-10-01

Temporomandibular joint osteoarthritis is a degenerative disease that is characterized by permanent cartilage destruction. Transforming growth factor (TGF)-β is one of the most abundant cytokines in the bone matrix and is shown to regulate the migration of osteoprogenitor cells. It is hypothesized that TGF-β/Smad3 signaling affects cartilage homeostasis by influencing sphingosine 1-phosphate (S1P)/S1P receptor signaling and chondrocyte migration. We therefore investigated the molecular mechanisms by which crosstalk may occur between TGF-β/Smad3 and S1P/S1P receptor signaling to maintain condylar cartilage and to prevent temporomandibular joint osteoarthritis. Abnormalities in the condylar subchondral bone, including dynamic changes in bone mineral density and microstructure, were observed in Smad3(-/-) mice by microcomputed tomography. Cell-free regions and proteoglycan loss characterized the cartilage degradation present, and increased numbers of apoptotic chondrocytes and matrix metalloproteinase 13(+) chondrocytes were also detected. Furthermore, expression of S1P receptor 3 (S1P3), but not S1P1 or S1P2, was significantly down-regulated in the condylar cartilage of Smad3(-/-) mice. By using RNA interference technology and pharmacologic tools, S1P was found to transactivate Smad3 in an S1P3/TGF-β type II receptor-dependent manner, and S1P3 was found to be required for TGF-β-induced migration of chondrocyte cells and downstream signal transduction via Rac1, RhoA, and Cdc42. Taken together, these results indicate that the Smad3/S1P3 signaling pathway plays an important role in the pathogenesis of temporomandibular joint osteoarthritis. Copyright © 2015 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

Sphingosine 1-Phosphate (S1P) Carrier-dependent Regulation of Endothelial Barrier

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Wilkerson, Brent A.; Grass, G. Daniel; Wing, Shane B.; Argraves, W. Scott; Argraves, Kelley M.

2012-01-01

Sphingosine 1-phosphate (S1P) is a blood-borne lysosphingolipid that acts to promote endothelial cell (EC) barrier function. In plasma, S1P is associated with both high density lipoproteins (HDL) and albumin, but it is not known whether the carriers impart different effects on S1P signaling. Here we establish that HDL-S1P sustains EC barrier longer than albumin-S1P. We showed that the sustained barrier effects of HDL-S1P are dependent on signaling by the S1P receptor, S1P1, and involve persistent activation of Akt and endothelial NOS (eNOS), as well as activity of the downstream NO target, soluble guanylate cyclase (sGC). Total S1P1 protein levels were found to be higher in response to HDL-S1P treatment as compared with albumin-S1P, and this effect was not associated with increased S1P1 mRNA or dependent on de novo protein synthesis. Several pieces of evidence indicate that long term EC barrier enhancement activity of HDL-S1P is due to specific effects on S1P1 trafficking. First, the rate of S1P1 degradation, which is proteasome-mediated, was slower in HDL-S1P-treated cells as compared with cells treated with albumin-S1P. Second, the long term barrier-promoting effects of HDL-S1P were abrogated by treatment with the recycling blocker, monensin. Finally, cell surface levels of S1P1 and levels of S1P1 in caveolin-enriched microdomains were higher after treatment with HDL-S1P as compared with albumin-S1P. Together, the findings reveal S1P carrier-specific effects on S1P1 and point to HDL as the physiological mediator of sustained S1P1-PI3K-Akt-eNOS-sGC-dependent EC barrier function. PMID:23135269

Tumor-associated endothelial cells display GSTP1 and RARβ2 promoter methylation in human prostate cancer

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Pohida Thomas J

2006-03-01

Full Text Available Abstract Background A functional blood supply is essential for tumor growth and proliferation. However, the mechanism of blood vessel recruitment to the tumor is still poorly understood. Ideally, a thorough molecular assessment of blood vessel cells would be critical in our comprehension of this process. Yet, to date, there is little known about the molecular makeup of the endothelial cells of tumor-associated blood vessels, due in part to the difficulty of isolating a pure population of endothelial cells from the heterogeneous tissue environment. Methods Here we describe the use of a recently developed technique, Expression Microdissection, to isolate endothelial cells from the tumor microenvironment. The methylation status of the dissected samples was evaluated for GSTP1 and RARβ2 promoters via the QMS-PCR method. Results Comparing GSTP1 and RARβ2 promoter methylation data, we show that 100% and 88% methylation is detected, respectively, in the tumor areas, both in epithelium and endothelium. Little to no methylation is observed in non-tumor tissue areas. Conclusion We applied an accurate microdissection technique to isolate endothelial cells from tissues, enabling DNA analysis such as promoter methylation status. The observations suggest that epigenetic alterations may play a role in determining the phenotype of tumor-associated vasculature.

Sphingosine 1-phosphate (S1P) induces COX-2 expression and PGE2 formation via S1P receptor 2 in renal mesangial cells.

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Völzke, Anja; Koch, Alexander; Meyer Zu Heringdorf, Dagmar; Huwiler, Andrea; Pfeilschifter, Josef

2014-01-01

Understanding the mechanisms of sphingosine 1-phosphate (S1P)-induced cyclooxygenase (COX)-2 expression and prostaglandin E2 (PGE2) formation in renal mesangial cells may provide potential therapeutic targets to treat inflammatory glomerular diseases. Thus, we evaluated the S1P-dependent signaling mechanisms which are responsible for enhanced COX-2 expression and PGE2 formation in rat mesangial cells under basal conditions. Furthermore, we investigated whether these mechanisms are operative in the presence of angiotensin II (Ang II) and of the pro-inflammatory cytokine interleukin-1β (IL-1β). Treatment of rat and human mesangial cells with S1P led to concentration-dependent enhanced expression of COX-2. Pharmacological and molecular biology approaches revealed that the S1P-dependent increase of COX-2 mRNA and protein expression was mediated via activation of S1P receptor 2 (S1P2). Further, inhibition of Gi and p42/p44 MAPK signaling, both downstream of S1P2, abolished the S1P-induced COX-2 expression. In addition, S1P/S1P2-dependent upregulation of COX-2 led to significantly elevated PGE2 levels, which were further potentiated in the presence of Ang II and IL-1β. A functional consequence downstream of S1P/S1P2 signaling is mesangial cell migration that is stimulated by S1P. Interestingly, inhibition of COX-2 by celecoxib and SC-236 completely abolished the migratory response. Overall, our results demonstrate that extracellular S1P induces COX-2 expression via activation of S1P2 and subsequent Gi and p42/p44 MAPK-dependent signaling in renal mesangial cells leading to enhanced PGE2 formation and cell migration that essentially requires COX-2. Thus, targeting S1P/S1P2 signaling pathways might be a novel strategy to treat renal inflammatory diseases. © 2013.

Improved wavelengths for the 1s2s3S1-1s2p3P0,2 transitions in helium-like Si12+

International Nuclear Information System (INIS)

Armour, I.A.; Myers, E.G.; Silver, J.D.; Traebert, E.; Oxford Univ.

1979-01-01

The wavelengths of the 1s2s 3 S 1 -1s2p 3 P 0 , 2 transitions in He-like Si 12+ have been remaesured to be 87.86 +- 0.01 nm and 81.48 +- 0.01 nm. The use of Rydberg lines for the calibration of fast beam spectra is discussed. (orig.)

Recognition and Detoxification of the Insecticide DDT by Drosophila melanogaster Glutathione S-Transferase D1

Energy Technology Data Exchange (ETDEWEB)

Low, Wai Yee; Feil, Susanne C.; Ng, Hooi Ling; Gorman, Michael A.; Morton, Craig J.; Pyke, James; McConville, Malcolm J.; Bieri, Michael; Mok, Yee-Foong; Robin, Charles; Gooley, Paul R.; Parker, Michael W.; Batterham, Philip (SVIMR-A); (Melbourne)

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 of 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.

Epigenetic regulation of pro-inflammatory cytokine secretion by sphingosine 1-phosphate (S1P) in acute lung injury: Role of S1P lyase.

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Ebenezer, David L; Fu, Panfeng; Suryadevara, Vidyani; Zhao, Yutong; Natarajan, Viswanathan

2017-01-01

Cellular level of sphingosine-1-phosphate (S1P), the simplest bioactive sphingolipid, is tightly regulated by its synthesis catalyzed by sphingosine kinases (SphKs) 1 & 2 and degradation mediated by S1P phosphatases, lipid phosphate phosphatases, and S1P lyase. The pleotropic actions of S1P are attributed to its unique inside-out (extracellular) signaling via G-protein-coupled S1P1-5 receptors, and intracellular receptor independent signaling. Additionally, S1P generated in the nucleus by nuclear SphK2 modulates HDAC1/2 activity, regulates histone acetylation, and transcription of pro-inflammatory genes. Here, we present data on the role of S1P lyase mediated S1P signaling in regulating LPS-induced inflammation in lung endothelium. Blocking S1P lyase expression or activity attenuated LPS-induced histone acetylation and secretion of pro-inflammatory cytokines. Degradation of S1P by S1P lyase generates Δ2-hexadecenal and ethanolamine phosphate and the long-chain fatty aldehyde produced in the cytoplasmic compartment of the endothelial cell seems to modulate histone acetylation pattern, which is different from the nuclear SphK2/S1P signaling and inhibition of HDAC1/2. These in vitro studies suggest that S1P derived long-chain fatty aldehyde may be an epigenetic regulator of pro-inflammatory genes in sepsis-induced lung inflammation. Trapping fatty aldehydes and other short chain aldehydes such as 4-hydroxynonenal derived from S1P degradation and lipid peroxidation, respectively by cell permeable agents such as phloretin or other aldehyde trapping agents may be useful in treating sepsis-induced lung inflammation via modulation of histone acetylation. . Copyright © 2016 Elsevier Ltd. All rights reserved.

Pathophysiological Consequences of a Break in S1P1-Dependent Homeostasis of Vascular Permeability Revealed by S1P1 Competitive Antagonism.

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Bigaud, Marc; Dincer, Zuhal; Bollbuck, Birgit; Dawson, Janet; Beckmann, Nicolau; Beerli, Christian; Fishli-Cavelti, Gina; Nahler, Michaela; Angst, Daniela; Janser, Philipp; Otto, Heike; Rosner, Elisabeth; Hersperger, Rene; Bruns, Christian; Quancard, Jean

2016-01-01

Homeostasis of vascular barriers depends upon sphingosine 1-phosphate (S1P) signaling via the S1P1 receptor. Accordingly, S1P1 competitive antagonism is known to reduce vascular barrier integrity with still unclear pathophysiological consequences. This was explored in the present study using NIBR-0213, a potent and selective S1P1 competitive antagonist. NIBR-0213 was tolerated at the efficacious oral dose of 30 mg/kg BID in the rat adjuvant-induced arthritis (AiA) model, with no sign of labored breathing. However, it induced dose-dependent acute vascular pulmonary leakage and pleural effusion that fully resolved within 3-4 days, as evidenced by MRI monitoring. At the supra-maximal oral dose of 300 mg/kg QD, NIBR-0213 impaired lung function (with increased breathing rate and reduced tidal volume) within the first 24 hrs. Two weeks of NIBR-0213 oral dosing at 30, 100 and 300 mg/kg QD induced moderate pulmonary changes, characterized by alveolar wall thickening, macrophage accumulation, fibrosis, micro-hemorrhage, edema and necrosis. In addition to this picture of chronic inflammation, perivascular edema and myofiber degeneration observed in the heart were also indicative of vascular leakage and its consequences. Overall, these observations suggest that, in the rat, the lung is the main target organ for the S1P1 competitive antagonism-induced acute vascular leakage, which appears first as transient and asymptomatic but could lead, upon chronic dosing, to lung remodeling with functional impairments. Hence, this not only raises the question of organ specificity in the homeostasis of vascular barriers, but also provides insight into the pre-clinical evaluation of a potential safety window for S1P1 competitive antagonists as drug candidates.

Selective coupling of the S1P3 receptor subtype to S1P-mediated RhoA activation and cardioprotection.

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Yung, Bryan S; Brand, Cameron S; Xiang, Sunny Y; Gray, Charles B B; Means, Christopher K; Rosen, Hugh; Chun, Jerold; Purcell, Nicole H; Brown, Joan Heller; Miyamoto, Shigeki

2017-02-01

Sphingosine-1-phosphate (S1P), a bioactive lysophospholipid, is generated and released at sites of tissue injury in the heart and can act on S1P 1 , S1P 2 , and S1P 3 receptor subtypes to affect cardiovascular responses. We established that S1P causes little phosphoinositide hydrolysis and does not induce hypertrophy indicating that it does not cause receptor coupling to G q . We previously demonstrated that S1P confers cardioprotection against ischemia/reperfusion by activating RhoA and its downstream effector PKD. The S1P receptor subtypes and G proteins that regulate RhoA activation and downstream responses in the heart have not been determined. Using siRNA or pertussis toxin to inhibit different G proteins in NRVMs we established that S1P regulates RhoA activation through Gα 13 but not Gα 12 , Gα q , or Gα i . Knockdown of the three major S1P receptors using siRNA demonstrated a requirement for S1P 3 in RhoA activation and subsequent phosphorylation of PKD, and this was confirmed in studies using isolated hearts from S1P 3 knockout (KO) mice. S1P treatment reduced infarct size induced by ischemia/reperfusion in Langendorff perfused wild-type (WT) hearts and this protection was abolished in the S1P 3 KO mouse heart. CYM-51736, an S1P 3 -specific agonist, also decreased infarct size after ischemia/reperfusion to a degree similar to that achieved by S1P. The finding that S1P 3 receptor- and Gα 13 -mediated RhoA activation is responsible for protection against ischemia/reperfusion suggests that selective targeting of S1P 3 receptors could provide therapeutic benefits in ischemic heart disease. Copyright © 2016 Elsevier Ltd. All rights reserved.

Interaction of integrin β4 with S1P receptors in S1P- and HGF-induced endothelial barrier enhancement.

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Ni, Xiuqin; Epshtein, Yulia; Chen, Weiguo; Zhou, Tingting; Xie, Lishi; Garcia, Joe G N; Jacobson, Jeffrey R

2014-06-01

We previously reported sphingosine 1-phosphate (S1P) and hepatocyte growth factor (HGF) augment endothelial cell (EC) barrier function and attenuate murine acute lung inury (ALI). While the mechanisms underlying these effects are not fully understood, S1P and HGF both transactivate the S1P receptor, S1PR1 and integrin β4 (ITGB4) at membrane caveolin-enriched microdomains (CEMs). In the current study, we investigated the roles of S1PR2 and S1PR3 in S1P/HGF-mediated EC signaling and their associations with ITGB4. Our studies confirmed ITGB4 and S1PR2/3 are recruited to CEMs in human lung EC in response to either S1P (1 µM, 5 min) or HGF (25 ng/ml, 5 min). Co-immunoprecipitation experiments identified an S1P/HGF-mediated interaction of ITGB4 with both S1PR2 and S1PR3. We then employed an in situ proximity ligation assay (PLA) to confirm a direct ITGB4-S1PR3 association induced by S1P/HGF although a direct association was not detectable between S1PR2 and ITGB4. S1PR1 knockdown (siRNA), however, abrogated S1P/HGF-induced ITGB4-S1PR2 associations while there was no effect on ITGB4-S1PR3 associations. Moreover, PLA confirmed a direct association between S1PR1 and S1PR2 induced by S1P and HGF. Finally, silencing of S1PR2 significantly attenuated S1P/HGF-induced EC barrier enhancement as measured by transendothelial resistance while silencing of S1PR3 significantly augmented S1P/HGF-induced barrier enhancement. These results confirm an important role for S1PR2 and S1PR3 in S1P/HGF-mediated EC barrier responses that are associated with their complex formation with ITGB4. Our findings elucidate novel mechanisms of EC barrier regulation that may ultimately lead to new therapeutic targets for disorders characterized by increased vascular permeability including ALI. © 2013 Wiley Periodicals, Inc.

Exogenous S1P Exposure Potentiates Ischemic Stroke Damage That Is Reduced Possibly by Inhibiting S1P Receptor Signaling.

Science.gov (United States)

Moon, Eunjung; Han, Jeong Eun; Jeon, Sejin; Ryu, Jong Hoon; Choi, Ji Woong; Chun, Jerold

2015-01-01

Initial and recurrent stroke produces central nervous system (CNS) damage, involving neuroinflammation. Receptor-mediated S1P signaling can influence neuroinflammation and has been implicated in cerebral ischemia through effects on the immune system. However, S1P-mediated events also occur within the brain itself where its roles during stroke have been less well studied. Here we investigated the involvement of S1P signaling in initial and recurrent stroke by using a transient middle cerebral artery occlusion/reperfusion (M/R) model combined with analyses of S1P signaling. Gene expression for S1P receptors and involved enzymes was altered during M/R, supporting changes in S1P signaling. Direct S1P microinjection into the normal CNS induced neuroglial activation, implicating S1P-initiated neuroinflammatory responses that resembled CNS changes seen during initial M/R challenge. Moreover, S1P microinjection combined with M/R potentiated brain damage, approximating a model for recurrent stroke dependent on S1P and suggesting that reduction in S1P signaling could ameliorate stroke damage. Delivery of FTY720 that removes S1P signaling with chronic exposure reduced damage in both initial and S1P-potentiated M/R-challenged brain, while reducing stroke markers like TNF-α. These results implicate direct S1P CNS signaling in the etiology of initial and recurrent stroke that can be therapeutically accessed by S1P modulators acting within the brain.

Exogenous S1P Exposure Potentiates Ischemic Stroke Damage That Is Reduced Possibly by Inhibiting S1P Receptor Signaling

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Eunjung Moon

2015-01-01

Full Text Available Initial and recurrent stroke produces central nervous system (CNS damage, involving neuroinflammation. Receptor-mediated S1P signaling can influence neuroinflammation and has been implicated in cerebral ischemia through effects on the immune system. However, S1P-mediated events also occur within the brain itself where its roles during stroke have been less well studied. Here we investigated the involvement of S1P signaling in initial and recurrent stroke by using a transient middle cerebral artery occlusion/reperfusion (M/R model combined with analyses of S1P signaling. Gene expression for S1P receptors and involved enzymes was altered during M/R, supporting changes in S1P signaling. Direct S1P microinjection into the normal CNS induced neuroglial activation, implicating S1P-initiated neuroinflammatory responses that resembled CNS changes seen during initial M/R challenge. Moreover, S1P microinjection combined with M/R potentiated brain damage, approximating a model for recurrent stroke dependent on S1P and suggesting that reduction in S1P signaling could ameliorate stroke damage. Delivery of FTY720 that removes S1P signaling with chronic exposure reduced damage in both initial and S1P-potentiated M/R-challenged brain, while reducing stroke markers like TNF-α. These results implicate direct S1P CNS signaling in the etiology of initial and recurrent stroke that can be therapeutically accessed by S1P modulators acting within the brain.

Gene Dose Effects of GSTM1, GSTT1 and GSTP1 Polymorphisms on Outcome in Childhood Acute Lymphoblastic Leukemia

DEFF Research Database (Denmark)

Borst, Louise; Buchard, Anders; Rosthoj, Susanne

2012-01-01

Children with acute lymphoblastic leukemia (ALL) react very differently to chemotherapy. One explanation for this is inherited genetic variation. The glutathione S-transferase (GST) enzymes inactivate a number of chemotherapeutic drugs administered in childhood ALL therapy. Two multiplexing methods...

Meat consumption, N-acetyl transferase 1 and 2 polymorphism and risk of breast cancer, in Danish postmenopausal women

DEFF Research Database (Denmark)

Egeberg, Rikke; Olsen, Anja; Autrup, Herman

2008-01-01

The aim of this study was to investigate whether polymorphisms in N-acetyl transferase 1 and 2 modify the association between meat consumption and risk of breast cancer. A nested case-control study was conducted among 24697 postmenopausal women included in the 'Diet, Cancer and Health' cohort study...... (1993-2000). Three hundred and seventy-eight breast cancer cases were identified and matched to 378 controls. The incidence rate ratio (95% confidence interval) for breast cancer was 1.09 (1.02-1.17) for total meat, 1.15 (1.01-1.31) for red meat and 1.23 (1.04-1.45) for processed meat per 25 g daily...... total meat intake and red meat intake and breast cancer risk were confined to intermediate/fast N-acetyl transferase 2 acetylators (P-interaction=0.03 and 0.04). Our findings support an association between meat consumption and breast cancer risk and that N-acetyl transferase 2 polymorphism has...

Association Study of Glutathione S-transferases Gene Polymorphisms (GSTM1 and GSTT1 with Ulcerative Colitis and Crohn's Disease in the South of Iran

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Maryam Moini

2017-01-01

Full Text Available Background: Inflammatory bowel diseases (IBDs, including ulcerative colitis (UC and Crohn's disease (CD, are chronic inflammatory disorders of the gastrointestinal tract. A combination of environmental factors and interactions with a genetic predisposition are suggested to play an important role in the etiology and pathogenesis of the IBD. Glutathione S-transferases (GSTs are multifunctional enzymes involved in the cellular oxidative stress handling. Possible associations between GSTs gene polymorphisms and susceptibility to UC and CD have been reported in different population. The relationship between GSTM1 and GSTT1 deletion polymorphisms and susceptibility to UC and CD were investigated in the Iranian population. Materials and Methods: The study was performed in 106 IBD patients and 243 age- and sex-matched healthy Iranian controls consulting the IBD registry center of the Motahari Clinic, Shiraz University of Medical Sciences, Shiraz, Iran, between 2011 and 2013. GSTM1 and GSTT1 genotyping were performed using multiplex polymerase chain reaction and differences in the distribution of gene polymorphisms were analyzed statistically between the studied groups. Results: Statistically significant higher frequency of GSTM1 null genotype was observed in IBD patients (P = 0.01 and in the subgroup of patients with UC (P = 0.04 compared to healthy controls, whereas this was not true for CD patients. No significant association was found between GSTT1 gene polymorphism and UC or CD. Conclusions: Absence of GSTT1 functional gene does not play an important role in the pathophysiology and development of IBD, UC, and CD in Iranian population whereas GSTM1 null genotype could be considered as a possible genetic predisposing factor for more susceptibility to IBD and UC.

Copy number variation in glutathione-S-transferase T1 and M1 predicts incidence and 5-year survival from prostate and bladder cancer, and incidence of corpus uteri cancer in the general population

DEFF Research Database (Denmark)

Nørskov, M S; Frikke-Schmidt, R; Bojesen, S E

2011-01-01

Glutathione-S-transferase T1 (GSTT1) and GSTM1 detoxify carcinogens and thus potentially contribute to inter-individual susceptibility to cancer. We determined the ability of GST copy number variation (CNV) to predict the risk of cancer in the general population. Exact copy numbers of GSTT1 and G...

The role of glutathione S-transferase and claudin-1 gene polymorphisms in contact sensitization

DEFF Research Database (Denmark)

Ross-Hansen, K; Linneberg, A; Johansen, J D

2013-01-01

BACKGROUND: Contact sensitization is frequent in the general population and arises from excessive or repeated skin exposure to chemicals and metals. However, little is known about its genetic susceptibility. OBJECTIVES: To determine the role of polymorphisms of glutathione S-transferase (GST) genes...

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

OpenAIRE

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

1994-01-01

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 ...

Possible gene dosage effect of glutathione-S-transferases on atopic asthma: using real-time PCR for quantification of GSTM1 and GSTT1 gene copy numbers

DEFF Research Database (Denmark)

Brasch-Andersen, Charlotte; Christiansen, L; Tan, Q

2004-01-01

-S-transferase (GST) involved in the antioxidant defense were tested for association to asthma using 246 Danish atopic families in a family-based transmission disequilibrium test (TDT) design. A real-time PCR assay for relative quantification of gene copy number of GSTM1 and GSTT1 was developed. The assay made......Asthma is a complex genetic disorder characterized by chronic inflammation in the airways. As oxidative stress is a key component of inflammation, variations in genes involved in antioxidant defense could therefore be likely candidates for asthma. Three enzymes from the superfamily glutathione...

Roles of sphingosine-1-phosphate (S1P) receptors in malignant behavior of glioma cells. Differential effects of S1P2 on cell migration and invasiveness

International Nuclear Information System (INIS)

Young, Nicholas; Van Brocklyn, James R.

2007-01-01

Sphingosine-1-phosphate (S1P) is a bioactive lipid that signals through a family of five G-protein-coupled receptors, termed S1P 1-5 . S1P stimulates growth and invasiveness of glioma cells, and high expression levels of the enzyme that forms S1P, sphingosine kinase-1, correlate with short survival of glioma patients. In this study we examined the mechanism of S1P stimulation of glioma cell proliferation and invasion by either overexpressing or knocking down, by RNA interference, S1P receptor expression in glioma cell lines. S1P 1 , S1P 2 and S1P 3 all contribute positively to S1P-stimulated glioma cell proliferation, with S1P 1 being the major contributor. Stimulation of glioma cell proliferation by these receptors correlated with activation of ERK MAP kinase. S1P 5 blocks glioma cell proliferation, and inhibits ERK activation. S1P 1 and S1P 3 enhance glioma cell migration and invasion. S1P 2 inhibits migration through Rho activation, Rho kinase signaling and stress fiber formation, but unexpectedly, enhances glioma cell invasiveness by stimulating cell adhesion. S1P 2 also potently enhances expression of the matricellular protein CCN1/Cyr61, which has been implicated in tumor cell adhesion, and invasion as well as tumor angiogenesis. A neutralizing antibody to CCN1 blocked S1P 2 -stimulated glioma invasion. Thus, while S1P 2 decreases glioma cell motility, it may enhance invasion through induction of proteins that modulate glioma cell interaction with the extracellular matrix

Glutathione S-transferase genotypes modify lung function decline in the general population: SAPALDIA cohort study

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Ackermann-Liebrich Ursula

2007-01-01

Full Text Available Abstract Background Understanding the environmental and genetic risk factors of accelerated lung function decline in the general population is a first step in a prevention strategy against the worldwide increasing respiratory pathology of chronic obstructive pulmonary disease (COPD. Deficiency in antioxidative and detoxifying Glutathione S-transferase (GST gene has been associated with poorer lung function in children, smokers and patients with respiratory diseases. In the present study, we assessed whether low activity variants in GST genes are also associated with accelerated lung function decline in the general adult population. Methods We examined with multiple regression analysis the association of polymorphisms in GSTM1, GSTT1 and GSTP1 genes with annual decline in FEV1, FVC, and FEF25–75 during 11 years of follow-up in 4686 subjects of the prospective SAPALDIA cohort representative of the Swiss general population. Effect modification by smoking, gender, bronchial hyperresponisveness and age was studied. Results The associations of GST genotypes with FEV1, FVC, and FEF25–75 were comparable in direction, but most consistent for FEV1. GSTT1 homozygous gene deletion alone or in combination with GSTM1 homozygous gene deletion was associated with excess decline in FEV1 in men, but not women, irrespective of smoking status. The additional mean annual decline in FEV1 in men with GSTT1 and concurrent GSTM1 gene deletion was -8.3 ml/yr (95% confidence interval: -12.6 to -3.9 relative to men without these gene deletions. The GSTT1 effect on the FEV1 decline comparable to the observed difference in FEV1 decline between never and persistent smoking men. Effect modification by gender was statistically significant. Conclusion Our results suggest that genetic GSTT1 deficiency is a prevalent and strong determinant of accelerated lung function decline in the male general population.

A role of the sphingosine-1-phosphate (S1P)-S1P receptor 2 pathway in epithelial defense against cancer (EDAC).

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Yamamoto, Sayaka; Yako, Yuta; Fujioka, Yoichiro; Kajita, Mihoko; Kameyama, Takeshi; Kon, Shunsuke; Ishikawa, Susumu; Ohba, Yusuke; Ohno, Yusuke; Kihara, Akio; Fujita, Yasuyuki

2016-02-01

At the initial step of carcinogenesis, transformation occurs in single cells within epithelia, where the newly emerging transformed cells are surrounded by normal epithelial cells. A recent study revealed that normal epithelial cells have an ability to sense and actively eliminate the neighboring transformed cells, a process named epithelial defense against cancer (EDAC). However, the molecular mechanism of this tumor-suppressive activity is largely unknown. In this study, we investigated a role for the sphingosine-1-phosphate (S1P)-S1P receptor 2 (S1PR2) pathway in EDAC. First, we show that addition of the S1PR2 inhibitor significantly suppresses apical extrusion of RasV12-transformed cells that are surrounded by normal cells. In addition, knockdown of S1PR2 in normal cells induces the same effect, indicating that S1PR2 in the surrounding normal cells plays a positive role in the apical elimination of the transformed cells. Of importance, not endogenous S1P but exogenous S1P is involved in this process. By using FRET analyses, we demonstrate that S1PR2 mediates Rho activation in normal cells neighboring RasV12-transformed cells, thereby promoting accumulation of filamin, a crucial regulator of EDAC. Collectively these data indicate that S1P is a key extrinsic factor that affects the outcome of cell competition between normal and transformed epithelial cells. © 2016 Yamamoto, Yako, et al. This article is distributed by The American Society for Cell Biology under license from the author(s). Two months after publication it is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

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

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Jobaida Akther

2016-01-01

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

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

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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

Glutathione S-transferase M1 and T1 null genotype frequency ...

Indian Academy of Sciences (India)

PREM CHANDRA SUTHAR

2018-03-24

Mar 24, 2018 ... A comparative analysis with different tribal as well as world population has also been ...... (GSTM1, T1 and P1) gene polymorphisms with type 2 diabetes mellitus .... from the Spanish Bladder Cancer Study and meta-analyses.

Polymorphisms of cytochrome P450 1A1, glutathione s-transferases M1 and T1 genes in ouangolodougou (Northern Ivory Coast

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Alfredo Santovito

2010-01-01

Full Text Available In this study, the frequencies of CYP1A1, GSTM1, and GSTT1 gene polymorphisms were determined in 133 healthy individuals from Ouangolodougou, a small rural town situated in the north of the Ivory Coast. As appeared in several published studies, ethnic differences in these frequencies have been found to play an important role in the metabolism of a relevant number of human carcinogens. In the studied sample, the frequencies of Ile/Ile (wild type, Ile/Val (heterozygous variant, and Val/Val (homozygous variant CYP1A1 genotypes were 0.271, 0.692, and 0.037, respectively. Frequencies of GSTM1 and GSTT1 null genotypes were 0.361 and 0.331, respectively. No significant differences were noted between men and women. In contrast to published data for Africans, CYP1A1 *Val Allele frequency (0.383 was significantly high (p < 0.001 in this specific population. For the GSTT1 null genotype, no differences were found between the studied and other African populations, the contrary to what occurred for the GSTM1 null genotype in relation to Gambia and Egypt.

Sphingosine kinase-1, S1P transporter spinster homolog 2 and S1P2 mRNA expressions are increased in liver with advanced fibrosis in human.

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Sato, Masaya; Ikeda, Hitoshi; Uranbileg, Baasanjav; Kurano, Makoto; Saigusa, Daisuke; Aoki, Junken; Maki, Harufumi; Kudo, Hiroki; Hasegawa, Kiyoshi; Kokudo, Norihiro; Yatomi, Yutaka

2016-08-26

The role of sphingosine 1-phosphate (S1P) in liver fibrosis or inflammation was not fully examined in human. Controversy exists which S1P receptors, S1P1 and S1P3 vs S1P2, would be importantly involved in its mechanism. To clarify these matters, 80 patients who received liver resection for hepatocellular carcinoma and 9 patients for metastatic liver tumor were enrolled. S1P metabolism was analyzed in background, non-tumorous liver tissue. mRNA levels of sphingosine kinase 1 (SK1) but not SK2 were increased in livers with fibrosis stages 3-4 compared to those with 0-2 and to normal liver. However, S1P was not increased in advanced fibrotic liver, where mRNA levels of S1P transporter spinster homolog 2 (SPNS2) but not S1P-degrading enzymes were enhanced. Furthermore, mRNA levels of S1P2 but not S1P1 or S1P3 were increased in advanced fibrotic liver. These increased mRNA levels of SK1, SPNS2 and S1P2 in fibrotic liver were correlated with α-smooth muscle actin mRNA levels in liver, and with serum ALT levels. In conclusion, S1P may be actively generated, transported to outside the cells, and bind to its specific receptor in human liver to play a role in fibrosis or inflammation. Altered S1P metabolism in fibrotic liver may be their therapeutic target.

The sphingosine 1-phosphate receptor S1P(2) triggers hepatic wound healing

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Serriere-Lanneau, Valerie; Teixeira-Clerc, Fatima; Li, Liying; Schippers, Marlies; de Wries, Willie; Julien, Boris; Tran-Van-Nhieu, Jeanne; Manin, Sylvie; Poelstra, Klaas; Chun, Jerold; Carpentier, Stephane; Levade, Thierry; Mallat, Ariane; Lotersztajn, Sophie

Sphingosine 1-phosphate (S1P) is a bioactive sphingolipid produced by sphingosine kinase (SphK1 and 2). We previously showed that S1P receptors (S1P(1), S1P(2), and S1P(3)) are expressed in hepatic myofibroblasts (hMF), a population of cells that triggers matrix remodeling during liver injury. Here

Targeting the SphK1/S1P/S1PR1 Axis That Links Obesity, Chronic Inflammation, and Breast Cancer Metastasis.

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Nagahashi, Masayuki; Yamada, Akimitsu; Katsuta, Eriko; Aoyagi, Tomoyoshi; Huang, Wei-Ching; Terracina, Krista P; Hait, Nitai C; Allegood, Jeremy C; Tsuchida, Junko; Yuza, Kizuki; Nakajima, Masato; Abe, Manabu; Sakimura, Kenji; Milstien, Sheldon; Wakai, Toshifumi; Spiegel, Sarah; Takabe, Kazuaki

2018-04-01

Although obesity with associated inflammation is now recognized as a risk factor for breast cancer and distant metastases, the functional basis for these connections remain poorly understood. Here, we show that in breast cancer patients and in animal breast cancer models, obesity is a sufficient cause for increased expression of the bioactive sphingolipid mediator sphingosine-1-phosphate (S1P), which mediates cancer pathogenesis. A high-fat diet was sufficient to upregulate expression of sphingosine kinase 1 (SphK1), the enzyme that produces S1P, along with its receptor S1PR1 in syngeneic and spontaneous breast tumors. Targeting the SphK1/S1P/S1PR1 axis with FTY720/fingolimod attenuated key proinflammatory cytokines, macrophage infiltration, and tumor progression induced by obesity. S1P produced in the lung premetastatic niche by tumor-induced SphK1 increased macrophage recruitment into the lung and induced IL6 and signaling pathways important for lung metastatic colonization. Conversely, FTY720 suppressed IL6, macrophage infiltration, and S1P-mediated signaling pathways in the lung induced by a high-fat diet, and it dramatically reduced formation of metastatic foci. In tumor-bearing mice, FTY720 similarly reduced obesity-related inflammation, S1P signaling, and pulmonary metastasis, thereby prolonging survival. Taken together, our results establish a critical role for circulating S1P produced by tumors and the SphK1/S1P/S1PR1 axis in obesity-related inflammation, formation of lung metastatic niches, and breast cancer metastasis, with potential implications for prevention and treatment. Significance: These findings offer a preclinical proof of concept that signaling by a sphingolipid may be an effective target to prevent obesity-related breast cancer metastasis. Cancer Res; 78(7); 1713-25. ©2018 AACR . ©2018 American Association for Cancer Research.

S1P and the birth of platelets

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Galvani, Sylvain; Rafii, Shahin; Nachman, Ralph

2012-01-01

Recent work has highlighted the multitude of biological functions of sphingosine 1-phosphate (S1P), which include roles in hematopoietic cell trafficking, organization of immune organs, vascular development, and neuroinflammation. Indeed, a functional antagonist of S1P1 receptor, FTY720/Gilenya, has entered the clinic as a novel therapeutic for multiple sclerosis. In this issue of the JEM, Zhang et al. highlight yet another function of this lipid mediator: thrombopoiesis. The S1P1 receptor is required for the growth of proplatelet strings in the bloodstream and the shedding of platelets into the circulation. Notably, the sharp gradient of S1P between blood and the interstitial fluids seems to be essential to ensure the production of platelets, and S1P appears to cooperate with the CXCL12–CXCR4 axis. Pharmacologic modulation of the S1P1 receptor altered circulating platelet numbers acutely, suggesting a potential therapeutic strategy for controlling thrombocytopenic states. However, the S1P4 receptor may also regulate thrombopoiesis during stress-induced accelerated platelet production. This work reveals a novel physiological action of the S1P/S1P1 duet that could potentially be harnessed for clinical translation. PMID:23166370

SIRT1 mediates Sphk1/S1P-induced proliferation and migration of endothelial cells.

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Gao, Zhan; Wang, Hua; Xiao, Feng-Jun; Shi, Xue-Feng; Zhang, Yi-Kun; Xu, Qin Qin; Zhang, Xiao-Yan; Ha, Xiao-Qin; Wang, Li-Sheng

2016-05-01

Angiogenesis is one of the most important components of embryonic organ formation and vessel growth after birth. Sphingosine kinase 1 (Sphk1) and S1P has been confirmed to participate in various cell signaling pathways and physiological processes including neovascularisation. However, the mechanisms that Sphk1/S1P regulates neovascularisation remain unclear. In this study, we elucidated that Sphk1/S1P upregulates sirtuin 1 (SIRT1), a NAD+ dependent deacetylases protease which exerts multiple cellular functions, to regulate the proliferation and migration of endothelial cells. By using CCK8 and Transwell assays, we demonstrated that Sphk1 and SIRT1 knockdown could significantly decrease proliferation and migration of HUVEC cells. Sphk1 inhibition results in SIRT1 downregulation which could be reversed by exogenous S1P in HUVEC cells. Treatment of HUVECs with S1P reverses the impaired proliferation and migration caused by SIRT1 knockdown. Furthermore, Sphk1 knockdown inhibits the phosphorylation of P38 MAPK, ERK and AKT. Treatment of HUVECs with PD98059, SB203580 and Wortmannin, which are the inhibitors of ERK, P38 MAPK and AKT respectively, resulted in decreased SIRT1 expression and reduced migration of HUVEC cells. Thus, we conclude that Sphk1/S1P induces SIRT1 upregulation through multiple pathways including P38 MAPK, ERK and AKT signals. This is the first report to disclose the existence and roles of Sphk1/S1P/SIRT1 axis in regulation of endothelial cell proliferation and migration, which may provide a theoretical basis for angiogenesis. Copyright © 2016. Published by Elsevier Ltd.

Gene polymorphisms of glutathione S-transferase omega 1 and 2, urinary arsenic methylation profile and urothelial carcinoma

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Chung, Chi-Jung [School of Public Health, College of Public Health and Nutrition, Taipei Medical University, Taipei, Taiwan (China); Pu, Yeong-Shiau [Department of Urology, National Taiwan University Hospital, Taipei, Taiwan (China); Su, Chien-Tien [Department of Family Medicine, Taipei Medical University Hospital, Taipei, Taiwan (China); Huang, Chao-Yuan [Department of Urology, National Taiwan University Hospital, Taipei, Taiwan (China); Graduate Institute of Clinical Medicine, College of Medicine, Taipei Medical University (China); Hsueh, Yu-Mei, E-mail: ymhsueh@tmu.edu.tw [School of Public Health, College of Public Health and Nutrition, Taipei Medical University, Taipei, Taiwan (China); Department of Public Health, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan (China)

2011-01-01

Genetic polymorphisms in arsenic-metabolizing enzymes may be involved in the biotransformation of inorganic arsenic and may increase the risk of developing urothelial carcinoma (UC). The present study evaluated the roles of glutathione S-transferase omega 1 (GSTO1) and GSTO2 polymorphisms in UC carcinogenesis. A hospital-based case-control study was conducted. Questionnaire information and biological specimens were collected from 149 UC cases and 251 healthy controls in a non-obvious inorganic arsenic exposure area in Taipei, Taiwan. The urinary arsenic profile was determined using high-performance liquid chromatography and hydride generator-atomic absorption spectrometry. Genotyping for GSTO1 Ala140Asp and GSTO2 Asn142Asp was conducted using polymerase chain reaction-restriction fragment length polymerase. GSTO1 Glu208Lys genotyping was performed using high-throughput matrix-assisted laser desorption and ionization time-of-flight mass spectrometry. A significant positive association was found between total arsenic, inorganic arsenic percentage and monomethylarsonic acid percentage and UC, while dimethylarsinic acid percentage was significantly inversely associated with UC. The minor allele frequency of GSTO1 Ala140Asp, GSTO1 Glu208Lys and GSTO2 Asn142Asp was 18%, 1% and 26%, respectively. A significantly higher MMA% was found in people who carried the wild type of GSTO1 140 Ala/Ala compared to those who carried the GSTO1 140 Ala/Asp and Asp/Asp genotype (p = 0.02). The homogenous variant genotype of GSTO2 142 Asp/Asp was inversely associated with UC risk (OR = 0.17; 95% CI, 0.03 - 0.88; p = 0.03). Large-scale studies will be required to verify the association between the single nucleotide polymorphisms of arsenic-metabolism-related enzymes and UC risk. - Research Highlights: {yields} The homogenous variant genotype of GSTO2 was inversely associated with UC risk. {yields} A higher urinary MMA% was found in people carrying the wild type of GSTO1 Ala140Asp. {yields

Electron Excitation Rate Coefficients for Transitions from the IS21S Ground State to the 1S2S1,3S and 1S2P1,3P0 Excited States of Helium

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Aggarwal, K. M.; Kingston, A. E.; McDowell, M. R. C.

1984-03-01

The available experimental and theoretical electron impact excitation cross section data for the transitions from the 1s2 1S ground state to the 1s2s 1,3S and 1s2p 1,3P0 excited states of helium are assessed. Based on this assessed data, excitation rate coefficients are calculated over a wide electron temperature range below 3.0×106K. A comparison with other published results suggests that the rates used should be lower by a factor of 2 or more.

Targeting the S1P/S1PR1 axis mitigates cancer-induced bone pain and neuroinflammation.

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Grenald, Shaness A; Doyle, Timothy M; Zhang, Hong; Slosky, Lauren M; Chen, Zhoumou; Largent-Milnes, Tally M; Spiegel, Sarah; Vanderah, Todd W; Salvemini, Daniela

2017-09-01

Metastatic bone pain is the single most common form of cancer pain and persists as a result of peripheral and central inflammatory, as well as neuropathic mechanisms. Here, we provide the first characterization of sphingolipid metabolism alterations in the spinal cord occurring during cancer-induced bone pain (CIBP). Following femoral arthrotomy and syngenic tumor implantation in mice, ceramides decreased with corresponding increases in sphingosine and the bioactive sphingolipid metabolite, sphingosine 1-phosphate (S1P). Intriguingly, de novo sphingolipid biosynthesis was increased as shown by the elevations of dihydro-ceramides and dihydro-S1P. We next identified the S1P receptor subtype 1 (S1PR1) as a novel target for therapeutic intervention. Intrathecal or systemic administration of the competitive and functional S1PR1 antagonists, TASP0277308 and FTY720/Fingolimod, respectively, attenuated cancer-induced spontaneous flinching and guarding. Inhibiting CIBP by systemic delivery of FTY720 did not result in antinociceptive tolerance over 7 days. FTY720 administration enhanced IL-10 in the lumbar ipsilateral spinal cord of CIBP animals and intrathecal injection of an IL-10 neutralizing antibody mitigated the ability of systemic FTY720 to reverse CIBP. FTY720 treatment was not associated with alterations in bone metabolism in vivo. Studies here identify a novel mechanism to inhibit bone cancer pain by blocking the actions of the bioactive metabolites S1P and dihydro-S1P in lumbar spinal cord induced by bone cancer and support potential fast-track clinical application of the FDA-approved drug, FTY720, as a therapeutic avenue for CIBP.

Late-stage optimization of a tercyclic class of S1P3-sparing, S1P1 receptor agonists.

Science.gov (United States)

Horan, Joshua C; Kuzmich, Daniel; Liu, Pingrong; DiSalvo, Darren; Lord, John; Mao, Can; Hopkins, Tamara D; Yu, Hui; Harcken, Christian; Betageri, Raj; Hill-Drzewi, Melissa; Patenaude, Lori; Patel, Monica; Fletcher, Kimberly; Terenzzio, Donna; Linehan, Brian; Xia, Heather; Patel, Mita; Studwell, Debbie; Miller, Craig; Hickey, Eugene; Levin, Jeremy I; Smith, Dustin; Kemper, Raymond A; Modis, Louise K; Bannen, Lynne C; Chan, Diva S; Mac, Morrison B; Ng, Stephanie; Wang, Yong; Xu, Wei; Lemieux, René M

2016-01-15

Poor solubility and cationic amphiphilic drug-likeness were liabilities identified for a lead series of S1P3-sparing, S1P1 agonists originally developed from a high-throughput screening campaign. This work describes the subsequent optimization of these leads by balancing potency, selectivity, solubility and overall molecular charge. Focused SAR studies revealed favorable structural modifications that, when combined, produced compounds with overall balanced profiles. The low brain exposure observed in rat suggests that these compounds would be best suited for the potential treatment of peripheral autoimmune disorders. Copyright © 2015 Elsevier Ltd. All rights reserved.

RAC1 P29S regulates PD-L1 expression in melanoma

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Vu, Ha Linh; Rosenbaum, Sheera; Purwin, Timothy J.; Davies, Michael A.; Aplin, Andrew E.

2015-01-01

Summary Whole exome sequencing of cutaneous melanoma has led to the detection of P29 mutations in RAC1 in 5–9% of samples, but the role of RAC1 P29 mutations in melanoma biology remains unclear. Using reverse phase protein array analysis to examine the changes in protein/phospho-protein expression, we identified cyclin B1, PD-L1, Ets-1, and Syk as being selectively upregulated with RAC1 P29S expression and downregulated with RAC1 P29S depletion. Using the melanoma patient samples in TCGA, we found PD-L1 expression to be significantly increased in RAC1 P29S patients compared to RAC1 WT as well as other RAC1 mutants. The finding that PD-L1 is upregulated suggests that oncogenic RAC1 P29S may promote suppression of the antitumor immune response. This is a new insight into the biological function of RAC1 P29S mutations with potential clinical implications as PD-L1 is a candidate biomarker for increased benefit from treatment with anti-PD1 or anti-PD-L1 antibodies. PMID:26176707

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

Science.gov (United States)

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

2005-01-01

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

Glutathione S-transferase M1 null genotype: lack of association with tumour characteristics and survival in advanced breast cancer

International Nuclear Information System (INIS)

Lizard-Nacol, Sarab; Coudert, Bruno; Colosetti, Pascal; Riedinger, Jean-Marc; Fargeot, Pierre; Brunet-Lecomte, Patrick

1999-01-01

Glutathione S-transferase (GST)M1, a member of the μ class GST gene family, has been shown to be polymorphic because of a partial gene deletion. This results in a failure to express the GSTM1 gene in 50-60% of individuals. Several studies have demonstrated a possible link with the GSTM1-null genotype and susceptibility to cancer. Furthermore, a GSTM1 isoenzyme has been positively associated with protective effect against mutagenic drugs, such as alkylating agents and anthracyclines. To determine whether GSTM1 polymorphisms are associated with tumour characteristics and survival in advanced breast cancer patients, and whether it may constitute a prognostic factor. We genotyped 92 patients receiving primary chemotherapy, which included cyclophosphamide, doxorubicine and 5-fluorouracil. The relationships between allelism at GSTM1 and clinicopathological parameters including age, menopausal status, tumour size, grade hormone receptors, involved nodes and p53 gene mutations were analysed. Of the patients with GSTM1-positive genotype, tissue samples obtained before and after treatment were available from 28 cases, allowing RNA extraction and GSTM1 expression by reverse transcription polymerase chain reaction. Relationships with clinical response to chemotherapy, and disease-free and overall survival were also evaluated. The data obtained was analysed using logistic regression to estimate the odds ratio and 95% confidence interval. Of 92 patients, 57.6% (n = 53) were classified as heritably GSTM1-deficient, and 42.4% (n = 39) were of the GSTM1-positive genotype. There were no statistically significant relationships between GSTM1-null genotype and the clinicopathological parameters analysed. No relationship was observed between GSTM1 RNA expression and objective clinical response to chemotherapy. Objective clinical response to chemotherapy was related only to clinical tumour size (P = 0.0177) and to the absence of intraductal carcinoma (P = 0.0013). GSTM1-null genotype

Berberine reduces fibronectin expression by suppressing the S1P-S1P2 receptor pathway in experimental diabetic nephropathy models.

Directory of Open Access Journals (Sweden)

Kaipeng Huang

Full Text Available The accumulation of glomerular extracellular matrix (ECM is one of the critical pathological characteristics of diabetic renal fibrosis. Fibronectin (FN is an important constituent of ECM. Our previous studies indicate that the activation of the sphingosine kinase 1 (SphK1-sphingosine 1- phosphate (S1P signaling pathway plays a key regulatory role in FN production in glomerular mesangial cells (GMCs under diabetic condition. Among the five S1P receptors, the activation of S1P2 receptor is the most abundant. Berberine (BBR treatment also effectively inhibits SphK1 activity and S1P production in the kidneys of diabetic models, thus improving renal injury. Based on these data, we further explored whether BBR could prevent FN production in GMCs under diabetic condition via the S1P2 receptor. Here, we showed that BBR significantly down-regulated the expression of S1P2 receptor in diabetic rat kidneys and GMCs exposed to high glucose (HG and simultaneously inhibited S1P2 receptor-mediated FN overproduction. Further, BBR also obviously suppressed the activation of NF-κB induced by HG, which was accompanied by reduced S1P2 receptor and FN expression. Taken together, our findings suggest that BBR reduces FN expression by acting on the S1P2 receptor in the mesangium under diabetic condition. The role of BBR in S1P2 receptor expression regulation could closely associate with its inhibitory effect on NF-κB activation.

A Prokaryotic S1P Lyase Degrades Extracellular S1P In Vitro and In Vivo: Implication for Treating Hyperproliferative Disorders

Science.gov (United States)

Huwiler, Andrea; Bourquin, Florence; Kotelevets, Nataliya; Pastukhov, Oleksandr; Capitani, Guido; Grütter, Markus G.; Zangemeister-Wittke, Uwe

2011-01-01

Sphingosine-1-phosphate (S1P) regulates a broad spectrum of fundamental cellular processes like proliferation, death, migration and cytokine production. Therefore, elevated levels of S1P may be causal to various pathologic conditions including cancer, fibrosis, inflammation, autoimmune diseases and aberrant angiogenesis. Here we report that S1P lyase from the prokaryote Symbiobacterium thermophilum (StSPL) degrades extracellular S1P in vitro and in blood. Moreover, we investigated its effect on cellular responses typical of fibrosis, cancer and aberrant angiogenesis using renal mesangial cells, endothelial cells, breast (MCF-7) and colon (HCT 116) carcinoma cells as disease models. In all cell types, wild-type StSPL, but not an inactive mutant, disrupted MAPK phosphorylation stimulated by exogenous S1P. Functionally, disruption of S1P receptor signaling by S1P depletion inhibited proliferation and expression of connective tissue growth factor in mesangial cells, proliferation, migration and VEGF expression in carcinoma cells, and proliferation and migration of endothelial cells. Upon intravenous injection of StSPL in mice, plasma S1P levels rapidly declined by 70% within 1 h and then recovered to normal 6 h after injection. Using the chicken chorioallantoic membrane model we further demonstrate that also under in vivo conditions StSPL, but not the inactive mutant, inhibited tumor cell-induced angiogenesis as an S1P-dependent process. Our data demonstrate that recombinant StSPL is active under extracellular conditions and holds promise as a new enzyme therapeutic for diseases associated with increased levels of S1P and S1P receptor signaling. PMID:21829623

Sphingosine 1-phosphate (S1P) signaling in glioblastoma multiforme-A systematic review.

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Mahajan-Thakur, Shailaja; Bien-Möller, Sandra; Marx, Sascha; Schroeder, Henry; Rauch, Bernhard H

2017-11-17

The multifunctional sphingosine-1-phosphate (S1P) is a lipid signaling molecule and central regulator in the development of several cancer types. In recent years, intriguing information has become available regarding the role of S1P in the progression of Glioblastoma multiforme (GBM), the most aggressive and common brain tumor in adults. S1P modulates numerous cellular processes in GBM, such as oncogenesis, proliferation and survival, invasion, migration, metastasis and stem cell behavior. These processes are regulated via a family of five G-protein-coupled S1P receptors (S1PR1-5) and may involve mainly unknown intracellular targets. Distinct expression patterns and multiple intracellular signaling pathways of each S1PR subtype enable S1P to exert its pleiotropic cellular actions. Several studies have demonstrated alterations in S1P levels, the involvement of S1PRs and S1P metabolizing enzymes in GBM pathophysiology. While the tumorigenic actions of S1P involve the activation of several kinases and transcription factors, the specific G-protein (Gi, Gq, and G12/13)-coupled signaling pathways and downstream mediated effects in GBM remain to be elucidated in detail. This review summarizes the recent findings concerning the role of S1P and its receptors in GBM. We further highlight the current insights into the signaling pathways considered fundamental for regulating the cellular processes in GMB and ultimately patient prognosis.

Differential transcription of cytochrome P450s and glutathione S transferases in DDT-susceptible and resistant Drosophila melanogaster strains in response to DDT and oxidative stress

Science.gov (United States)

Metabolic DDT resistance in Drosophila melanogaster has previously been associated with constitutive over-transcription of cytochrome P450s. Increased P450 activity has also been associated with increased oxidative stress. In contrast, over-transcription of glutathione S transferases (GSTs) has been...

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

Science.gov (United States)

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.

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

Science.gov (United States)

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.

Association of single nucleotide polymorphisms in the genes ATM, GSTP1, SOD2, TGFB1, XPD and XRCC1 with risk of severe erythema after breast conserving radiotherapy

International Nuclear Information System (INIS)

Raabe, Annette; Derda, Katharina; Reuther, Sebastian; Szymczak, Silke; Borgmann, Kerstin; Hoeller, Ulrike; Ziegler, Andreas; Petersen, Cordula; Dikomey, Ekkehard

2012-01-01

To examine the association of polymorphisms in ATM (codon 158), GSTP1 (codon 105), SOD2 (codon 16), TGFB1 (position −509), XPD (codon 751), and XRCC1 (codon 399) with the risk of severe erythema after breast conserving radiotherapy. Retrospective analysis of 83 breast cancer patients treated with breast conserving radiotherapy. A total dose of 50.4 Gy was administered, applying 1.8 Gy/fraction within 42 days. Erythema was evaluated according to the Radiation Therapy Oncology Group (RTOG) score. DNA was extracted from blood samples and polymorphisms were determined using either the Polymerase Chain Reaction based Restriction-Fragment-Length-Polymorphism (PCR-RFL) technique or Matrix-Assisted-Laser-Desorption/Ionization –Time-Of-Flight-Mass-Spectrometry (MALDI-TOF). Relative excess heterozygosity (REH) was investigated to check compatibility of genotype frequencies with Hardy-Weinberg equilibrium (HWE). In addition, p-values from the standard exact HWE lack of fit test were calculated using 100,000 permutations. HWE analyses were performed using R. Fifty-six percent (46/83) of all patients developed erythema of grade 2 or 3, with this risk being higher for patients with large breast volume (odds ratio, OR = 2.55, 95% confidence interval, CI: 1.03–6.31, p = 0.041). No significant association between SNPs and risk of erythema was found when all patients were considered. However, in patients with small breast volume the TGFB1 SNP was associated with erythema (p = 0.028), whereas the SNP in XPD showed an association in patients with large breast volume (p = 0.046). A risk score based on all risk alleles was neither significant in all patients nor in patients with small or large breast volume. Risk alleles of most SNPs were different compared to a previously identified risk profile for fibrosis. The genetic risk profile for erythema appears to be different for patients with small and larger breast volume. This risk profile seems to be specific for erythema as

Structural Redesigning Arabidopsis Lignins into Alkali-Soluble Lignins through the Expression of p-Coumaroyl-CoA:Monolignol Transferase PMT1

Science.gov (United States)

Sibout, Richard; Le Bris, Philippe; Cézard, Laurent

2016-01-01

Grass lignins can contain up to 10% to 15% by weight of p-coumaric esters. This acylation is performed on monolignols under the catalysis of p-coumaroyl-coenzyme A monolignol transferase (PMT). To study the impact of p-coumaroylation on lignification, we first introduced the Brachypodium distachyon Bradi2g36910 (BdPMT1) gene into Arabidopsis (Arabidopsis thaliana) under the control of the constitutive maize (Zea mays) ubiquitin promoter. The resulting p-coumaroylation was far lower than that of lignins from mature grass stems and had no impact on stem lignin content. By contrast, introducing either the BdPMT1 or the Bradi1g36980 (BdPMT2) gene into Arabidopsis under the control of the Arabidopsis cinnamate-4-hydroxylase promoter boosted the p-coumaroylation of mature stems up to the grass lignin level (8% to 9% by weight), without any impact on plant development. The analysis of purified lignin fractions and the identification of diagnostic products confirmed that p-coumaric acid was associated with lignins. BdPMT1-driven p-coumaroylation was also obtained in the fah1 (deficient for ferulate 5-hydroxylase) and ccr1g (deficient for cinnamoyl-coenzyme A reductase) lines, albeit to a lower extent. Lignins from BdPMT1-expressing ccr1g lines were also found to be feruloylated. In Arabidopsis mature stems, substantial p-coumaroylation of lignins was achieved at the expense of lignin content and induced lignin structural alterations, with an unexpected increase of lignin units with free phenolic groups. This higher frequency of free phenolic groups in Arabidopsis lignins doubled their solubility in alkali at room temperature. These findings suggest that the formation of alkali-leachable lignin domains rich in free phenolic groups is favored when p-coumaroylated monolignols participate in lignification in a grass in a similar manner. PMID:26826222

Electron impact excitation-autoionisation of the (2s2)1S, (2p2)1D and (2s2p)1P autoionising states of helium

International Nuclear Information System (INIS)

Samardzic, O.; Hurn, J.A.; Weigold, E.; Brunger, M.J.

1994-01-01

The electron impact excitation of the (2s 2 ) 1 S, (2p 2 ) 1 D and (2s2p) 1 P autoionising states of helium and their subsequent radiationless decay was studied by observation of the ejected electrons. The present work was carried out at an incident energy of 94.6 eV and for ejected electron scattering angles in the range 25-135 deg C. The lineshapes observed in the present ejected electron spectra are analysed using the Shore-Balashov parametrisation. As part of the analysis procedure, numerically rigorous confidence limits were determined for the derived parameters. No previous experimental or theoretical work has been undertaken at the incident energy of the present investigation but, where possible, the resulting parameters are qualitatively compared against the 80 eV results of other experiments and theory. 37 refs., 4 figs

Quantum Mechanical/Molecular Mechanical Free Energy Simulations of the Glutathione S-Transferase (M1-1) Reaction with Phenanthrene 9,10-Oxide

NARCIS (Netherlands)

Ridder, L.; Rietjens, I.M.C.M.; Vervoort, J.J.M.; Mulholland, A.J.

2002-01-01

Glutathione S-transferases (GSTs) play an important role in the detoxification of xenobiotics in mammals. They catalyze the conjugation of glutathione to a wide range of electrophilic compounds. Phenanthrene 9,10-oxide is a model substrate for GSTs, representing an important group of epoxide

Identification of the 1s2s2p 4P5/2-->1s22s 2S1/2 magnetic quadrupole inner-shell satellite line in the Ar16+ K-shell x-ray spectrum

Science.gov (United States)

Beiersdorfer, P.; Bitter, M.; Hey, D.; Reed, K. J.

2002-09-01

We have identified the dipole-forbidden 1s2s2p 4P5/2-->1s22s 2S1/2 transition in lithiumlike Ar15+ in high-resolution K-shell x-ray emission spectra recorded at the Livermore EBIT-II electron-beam ion trap and the Princeton National Spherical Tokamak Experiment. Unlike other Ar15+ satellite lines, which can be excited by dielectronic recombination, the line is exclusively excited by electron-impact excitation. Its predicted radiative rate is comparable to that of the well-known 1s2p 3P1-->1s2 1S0 magnetic quadrupole transition in heliumlike Ar16+. As a result, it can also only be observed in low-density plasma. We present calculations of the electron-impact excitation cross sections of the innershell excited Ar15+ satellite lines, including the magnetic sublevels needed for calculating the linear line polarization. We compare these calculations to the relative magnitudes of the observed 1s2s2p-->1s22s transitions and find good agreement, confirming the identification of the lithiumlike 1s2s2p 4P5/2-->1s22s 2S1/2 magnetic quadrupole line.

Sphingosine-1-Phosphate Induces Dose-Dependent Chemotaxis or Fugetaxis of T-ALL Blasts through S1P1 Activation

Science.gov (United States)

Messias, Carolina V.; Santana-Van-Vliet, Eliane; Lemos, Julia P.; Moreira, Otacilio C.; Cotta-de-Almeida, Vinicius; Savino, Wilson; Mendes-da-Cruz, Daniella Arêas

2016-01-01

Sphingosine-1-phosphate (S1P) is a bioactive sphingolipid involved in several physiological processes including cell migration and differentiation. S1P signaling is mediated through five G protein-coupled receptors (S1P1-S1P5). S1P1 is crucial to the exit of T-lymphocytes from the thymus and peripheral lymphoid organs through a gradient of S1P. We have previously observed that T-ALL and T-LBL blasts express S1P1. Herein we analyzed the role of S1P receptors in the migratory pattern of human T-cell neoplastic blasts. S1P-triggered cell migration was directly related to S1P1 expression. T-ALL blasts expressing low levels of S1P1 mRNA (HPB-ALL) did not migrate toward S1P, whereas those expressing higher levels of S1P1 (MOLT-4, JURKAT and CEM) did migrate. The S1P ligand induced T-ALL cells chemotaxis in concentrations up to 500 nM and induced fugetaxis in higher concentrations (1000–10000 nM) through interactions with S1P1. When S1P1 was specifically blocked by the W146 compound, S1P-induced migration at lower concentrations was reduced, whereas higher concentrations induced cell migration. Furthermore, we observed that S1P/S1P1 interactions induced ERK and AKT phosphorylation, and modulation of Rac1 activity. Responding T-ALL blasts also expressed S1P3 mRNA but blockage of this receptor did not modify migratory responses. Our results indicate that S1P is involved in the migration of T-ALL/LBL blasts, which is dependent on S1P1 expression. Moreover, S1P concentrations in the given microenvironment might induce dose-dependent chemotaxis or fugetaxis of T-ALL blasts. PMID:26824863

Sphingosine-1-Phosphate Induces Dose-Dependent Chemotaxis or Fugetaxis of T-ALL Blasts through S1P1 Activation.

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Carolina V Messias

Full Text Available Sphingosine-1-phosphate (S1P is a bioactive sphingolipid involved in several physiological processes including cell migration and differentiation. S1P signaling is mediated through five G protein-coupled receptors (S1P1-S1P5. S1P1 is crucial to the exit of T-lymphocytes from the thymus and peripheral lymphoid organs through a gradient of S1P. We have previously observed that T-ALL and T-LBL blasts express S1P1. Herein we analyzed the role of S1P receptors in the migratory pattern of human T-cell neoplastic blasts. S1P-triggered cell migration was directly related to S1P1 expression. T-ALL blasts expressing low levels of S1P1 mRNA (HPB-ALL did not migrate toward S1P, whereas those expressing higher levels of S1P1 (MOLT-4, JURKAT and CEM did migrate. The S1P ligand induced T-ALL cells chemotaxis in concentrations up to 500 nM and induced fugetaxis in higher concentrations (1000-10000 nM through interactions with S1P1. When S1P1 was specifically blocked by the W146 compound, S1P-induced migration at lower concentrations was reduced, whereas higher concentrations induced cell migration. Furthermore, we observed that S1P/S1P1 interactions induced ERK and AKT phosphorylation, and modulation of Rac1 activity. Responding T-ALL blasts also expressed S1P3 mRNA but blockage of this receptor did not modify migratory responses. Our results indicate that S1P is involved in the migration of T-ALL/LBL blasts, which is dependent on S1P1 expression. Moreover, S1P concentrations in the given microenvironment might induce dose-dependent chemotaxis or fugetaxis of T-ALL blasts.

[GSTP1, APC and RASSF1 gene methylation in prostate cancer samples: comparative analysis of MS-HRM method and Infinium HumanMethylation450 BeadChip beadchiparray diagnostic value].

Science.gov (United States)

Skorodumova, L O; Babalyan, K A; Sultanov, R; Vasiliev, A O; Govorov, A V; Pushkar, D Y; Prilepskaya, E A; Danilenko, S A; Generozov, E V; Larin, A K; Kostryukova, E S; Sharova, E I

2016-11-01

There is a clear need in molecular markers for prostate cancer (PC) risk stratification. Alteration of DNA methylation is one of processes that occur during ÐÑ progression. Methylation-sensitive PCR with high resolution melting curve analysis (MS-HRM) can be used for gene methylation analysis in routine laboratory practice. This method requires very small amounts of DNA for analysis. Numerous results have been accumulated on DNA methylation in PC samples analyzed by the Infinium HumanMethylation450 BeadChip (HM450). However, the consistency of MS-HRM results with chip hybridization results has not been examined yet. The aim of this study was to assess the consistency of results of GSTP1, APC and RASSF1 gene methylation analysis in ÐÑ biopsy samples obtained by MS-HRM and chip hybridization. The methylation levels of each gene determined by MS-HRM were statistically different in the group of PC tissue samples and the samples without signs of tumor growth. Chip hybridization data analysis confirmed the results obtained with the MS-HRM. Differences in methylation levels between tumor tissue and histologically intact tissue of each sample determined by MS-HRM and chip hybridization, were consistent with each other. Thus, we showed that the assessment of GSTP1, APC and RASSF1 gene methylation analysis using MS-HRM is suitable for the design of laboratory assays that will differentiate the PC tissue from the tissue without signs of tumor growth.

Oncogenic S1P signalling in EBV-associated nasopharyngeal carcinoma activates AKT and promotes cell migration through S1P receptor 3.

Science.gov (United States)

Lee, Hui Min; Lo, Kwok-Wai; Wei, Wenbin; Tsao, Sai Wah; Chung, Grace Tin Yun; Ibrahim, Maha Hafez; Dawson, Christopher W; Murray, Paul G; Paterson, Ian C; Yap, Lee Fah

2017-05-01

Undifferentiated nasopharyngeal carcinoma (NPC) is a cancer with high metastatic potential that is consistently associated with Epstein-Barr virus (EBV) infection. In this study, we have investigated the functional contribution of sphingosine-1-phosphate (S1P) signalling to the pathogenesis of NPC. We show that EBV infection or ectopic expression of the EBV-encoded latent genes (EBNA1, LMP1, and LMP2A) can up-regulate sphingosine kinase 1 (SPHK1), the key enzyme that produces S1P, in NPC cell lines. Exogenous addition of S1P promotes the migration of NPC cells through the activation of AKT; shRNA knockdown of SPHK1 resulted in a reduction in the levels of activated AKT and inhibition of cell migration. We also show that S1P receptor 3 (S1PR3) mRNA is overexpressed in EBV-positive NPC patient-derived xenografts and a subset of primary NPC tissues, and that knockdown of S1PR3 suppressed the activation of AKT and the S1P-induced migration of NPC cells. Taken together, our data point to a central role for EBV in mediating the oncogenic effects of S1P in NPC and identify S1P signalling as a potential therapeutic target in this disease. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Mechanism of Folding and Activation of Subtilisin Kexin Isozyme-1 (SKI-1)/Site-1 Protease (S1P)*

Science.gov (United States)

da Palma, Joel Ramos; Cendron, Laura; Seidah, Nabil Georges; Pasquato, Antonella; Kunz, Stefan

2016-01-01

The proprotein convertase subtilisin kexin isozyme-1 (SKI-1)/site-1 protease (S1P) is implicated in lipid homeostasis, the unfolded protein response, and lysosome biogenesis. The protease is further hijacked by highly pathogenic emerging viruses for the processing of their envelope glycoproteins. Zymogen activation of SKI-1/S1P requires removal of an N-terminal prodomain, by a multistep process, generating the mature enzyme. Here, we uncover a modular structure of the human SKI-1/S1P prodomain and define its function in folding and activation. We provide evidence that the N-terminal AB fragment of the prodomain represents an autonomous structural and functional unit that is necessary and sufficient for folding and partial activation. In contrast, the C-terminal BC fragment lacks a defined structure but is crucial for autoprocessing and full catalytic activity. Phylogenetic analysis revealed that the sequence of the AB domain is highly conserved, whereas the BC fragment shows considerable variation and seems even absent in some species. Notably, SKI-1/S1P of arthropods, like the fruit fly Drosophila melanogaster, contains a shorter prodomain comprised of full-length AB and truncated BC regions. Swapping the prodomain fragments between fly and human resulted in a fully mature and active SKI-1/S1P chimera. Our study suggests that primordial SKI-1/S1P likely contained a simpler prodomain consisting of the highly conserved AB fragment that represents an independent folding unit. The BC region appears as a later evolutionary acquisition, possibly allowing more subtle fine-tuning of the maturation process. PMID:26645686

Vitamin D attenuates sphingosine-1-phosphate (S1P)-mediated inhibition of extravillous trophoblast migration.

Science.gov (United States)

Westwood, Melissa; Al-Saghir, Khiria; Finn-Sell, Sarah; Tan, Cherlyn; Cowley, Elizabeth; Berneau, Stéphane; Adlam, Daman; Johnstone, Edward D

2017-12-01

Failure of trophoblast invasion and remodelling of maternal blood vessels leads to the pregnancy complication pre-eclampsia (PE). In other systems, the sphingolipid, sphingosine-1-phosphate (S1P), controls cell migration therefore this study determined its effect on extravillous trophoblast (EVT) function. A transwell migration system was used to assess the behaviour of three trophoblast cell lines, Swan-71, SGHPL-4, and JEG3, and primary human trophoblasts in the presence or absence of S1P, S1P pathway inhibitors and 1,25(OH) 2 D 3 . QPCR and immunolocalisation were used to demonstrate EVT S1P receptor expression. EVTs express S1P receptors 1, 2 and 3. S1P inhibited EVT migration. This effect was abolished in the presence of the specific S1PR2 inhibitor, JTE-013 (p S1P alone) whereas treatment with the S1R1/3 inhibitor, FTY720, had no effect. In other cell types S1PR2 is regulated by vitamin D; here we found that treatment with 1,25(OH) 2 D 3 for 48 or 72 h reduces S1PR2 (4-fold; S1P did not inhibit the migration of cells exposed to 1,25(OH) 2 D 3 (p S1P receptor isoforms, S1P predominantly signals through S1PR2/Gα 12/13 to activate Rho and thereby acts as potent inhibitor of EVT migration. Importantly, expression of S1PR2, and therefore S1P function, can be down-regulated by vitamin D. Our data suggest that vitamin D deficiency, which is known to be associated with PE, may contribute to the impaired trophoblast migration that underlies this condition. Copyright © 2017 Elsevier Ltd. All rights reserved.

Is Increased Susceptibility to Balkan Endemic Nephropathy in Carriers of Common GSTA1 (*A/*B Polymorphism Linked with the Catalytic Role of GSTA1 in Ochratoxin A Biotransformation? Serbian Case Control Study and In Silico Analysis

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Zorica Reljic

2014-08-01

Full Text Available Although recent data suggest aristolochic acid as a putative cause of Balkan endemic nephropathy (BEN, evidence also exists in favor of ochratoxin A (OTA exposure as risk factor for the disease. The potential role of xenobiotic metabolizing enzymes, such as the glutathione transferases (GSTs, in OTA biotransformation is based on OTA glutathione adducts (OTHQ-SG and OTB-SG in blood and urine of BEN patients. We aimed to analyze the association between common GSTA1, GSTM1, GSTT1, and GSTP1 polymorphisms and BEN susceptibility, and thereafter performed an in silico simulation of particular GST enzymes potentially involved in OTA transformations. GSTA1, GSTM1, GSTT1 and GSTP1 genotypes were determined in 207 BEN patients and 138 non-BEN healthy individuals from endemic regions by polymerase chain reaction (PCR. Molecular modeling in silico was performed for GSTA1 protein. Among the GST polymorphisms tested, only GSTA1 was significantly associated with a higher risk of BEN. Namely, carriers of the GSTA1*B gene variant, associated with lower transcriptional activation, were at a 1.6-fold higher BEN risk than those carrying the homozygous GSTA1*A/*A genotype (OR = 1.6; p = 0.037. In in silico modeling, we found four structures, two OTB-SG and two OTHQ-SG, bound in a GSTA1 monomer. We found that GSTA1 polymorphism was associated with increased risk of BEN, and suggested, according to the in silico simulation, that GSTA1-1 might be involved in catalyzing the formation of OTHQ-SG and OTB-SG conjugates.

Expression of an enzymatically active Yb3 glutathione S-transferase in Escherichia coli and identification of its natural form in rat brain.

Science.gov (United States)

Abramovitz, M; Ishigaki, S; Felix, A M; Listowsky, I

1988-11-25

Glutathione S-transferases containing Yb3 subunits are relatively uncommon forms that are expressed in a tissue-specific manner and have not been identified unequivocally or characterized. A cDNA clone containing the entire coding sequence of Yb3 glutathione S-transferase mRNA was incorporated into a pIN-III expression vector used to transform Escherichia coli. A fusion Yb3-protein containing 14 additional amino acid residues at its N terminus was purified to homogeneity. Recombinant Yb3 was enzymatically active with both 1-chloro-2,4-dinitrobenzene and 1,2-dichloro-4-nitrobenzene as substrates but lacked glutathione peroxidase activity. Substrate specificity patterns of recombinant Yb3 were more limited than those of glutathione S-transferase isoenzymes containing Yb1- or Yb2-type subunits. Peptides corresponding to unique amino acid sequences of Yb3 as well as a peptide from a region of homology with Yb1 and Yb2 subunits were synthesized. These synthetic peptides were used to raise antibodies specific to Yb3 and others that cross-reacted with all Yb forms. Immunoblotting was utilized to identify the natural counterpart of recombinant Yb3 among rat glutathione transferases. Brain and testis glutathione S-transferases were rich in Yb3 subunits, but very little was found in liver or kidney. Physical properties, substrate specificities, and binding patterns of the recombinant protein paralleled properties of the natural isoenzyme isolated from brain.

Mechanism of Folding and Activation of Subtilisin Kexin Isozyme-1 (SKI-1)/Site-1 Protease (S1P).

Science.gov (United States)

da Palma, Joel Ramos; Cendron, Laura; Seidah, Nabil Georges; Pasquato, Antonella; Kunz, Stefan

2016-01-29

The proprotein convertase subtilisin kexin isozyme-1 (SKI-1)/site-1 protease (S1P) is implicated in lipid homeostasis, the unfolded protein response, and lysosome biogenesis. The protease is further hijacked by highly pathogenic emerging viruses for the processing of their envelope glycoproteins. Zymogen activation of SKI-1/S1P requires removal of an N-terminal prodomain, by a multistep process, generating the mature enzyme. Here, we uncover a modular structure of the human SKI-1/S1P prodomain and define its function in folding and activation. We provide evidence that the N-terminal AB fragment of the prodomain represents an autonomous structural and functional unit that is necessary and sufficient for folding and partial activation. In contrast, the C-terminal BC fragment lacks a defined structure but is crucial for autoprocessing and full catalytic activity. Phylogenetic analysis revealed that the sequence of the AB domain is highly conserved, whereas the BC fragment shows considerable variation and seems even absent in some species. Notably, SKI-1/S1P of arthropods, like the fruit fly Drosophila melanogaster, contains a shorter prodomain comprised of full-length AB and truncated BC regions. Swapping the prodomain fragments between fly and human resulted in a fully mature and active SKI-1/S1P chimera. Our study suggests that primordial SKI-1/S1P likely contained a simpler prodomain consisting of the highly conserved AB fragment that represents an independent folding unit. The BC region appears as a later evolutionary acquisition, possibly allowing more subtle fine-tuning of the maturation process. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

Chemical and genetic tools to explore S1P biology.

Science.gov (United States)

Cahalan, Stuart M

2014-01-01

The zwitterionic lysophospholipid Sphingosine 1-Phosphate (S1P) is a pleiotropic mediator of physiology and pathology. The synthesis, transport, and degradation of S1P are tightly regulated to ensure that S1P is present in the proper concentrations in the proper location. The binding of S1P to five G protein-coupled S1P receptors regulates many physiological systems, particularly the immune and vascular systems. Our understanding of the functions of S1P has been aided by the tractability of the system to both chemical and genetic manipulation. Chemical modulators have been generated to affect most of the known components of S1P biology, including agonists of S1P receptors and inhibitors of enzymes regulating S1P production and degradation. Genetic knockouts and manipulations have been similarly engineered to disrupt the functions of individual S1P receptors or enzymes involved in S1P metabolism. This chapter will focus on the development and utilization of these chemical and genetic tools to explore the complex biology surrounding S1P and its receptors, with particular attention paid to the in vivo findings that these tools have allowed for.

Disruption of Smad-dependent signaling for growth of GST-P-positive lesions from the early stage in a rat two-stage hepatocarcinogenesis model

International Nuclear Information System (INIS)

Ichimura, Ryohei; Mizukami, Sayaka; Takahashi, Miwa; Taniai, Eriko; Kemmochi, Sayaka; Mitsumori, Kunitoshi; Shibutani, Makoto

2010-01-01

To clarify the involvement of signaling of transforming growth factor (TGF)-β during the hepatocarcinogenesis, the immunohistochemical distribution of related molecules was analyzed in relation with liver cell lesions expressing glutathione S-transferase placental form (GST-P) during liver tumor promotion by fenbendazole, phenobarbital, piperonyl butoxide, or thioacetamide, using rats. Our study focused on early-stage promotion (6 weeks after starting promotion) and late-stage promotion (57 weeks after starting promotion). With regard to Smad-dependent signaling, cytoplasmic accumulation of phosphorylated Smad (phospho-Smad)-2/3 - identified as Smad3 by later immunoblot analysis - increased in the subpopulation of GST-P + foci, while Smad4, a nuclear transporter of Smad2/3, decreased during early-stage promotion. By late-stage promotion, GST-P + lesions lacking phospho-Smad2/3 had increased in accordance with lesion development from foci to carcinomas, while Smad4 largely disappeared in most proliferative lesions. With regard to Smad-independent mitogen-activated protein kinases, GST-P + foci that co-expressed phospho-p38 mitogen-activated protein kinase increased during early-stage promotion; however, p38-downstream phospho-activating transcriptional factor (ATF)-2, ATF3, and phospho-c-Myc, were inversely downregulated without relation to promotion. By late-stage promotion, proliferative lesions downregulated phospho-ATF2 and phospho-c-Myc along with lesion development, as with downregulation of phospho-p38 in all lesions. These results suggest that from the early stages, carcinogenic processes were facilitated by disruption of tumor suppressor functions of Smad-dependent signaling, while Smad-independent activation of p38 was an early-stage phenomenon. GST-P - foci induced by promotion with agonists of peroxisome proliferator-activated receptor-α did not change Smad expression, suggesting an aberration in the Smad-dependent signaling prerequisites for induction

Females with paired occurrence of cancers in the UADT and genital region have a higher frequency of either Glutathione S-transferase M1/T1 null genotype

Directory of Open Access Journals (Sweden)

Jhavar Sameer G

2005-03-01

Full Text Available Abstract Upper Aero digestive Tract (UADT is the commonest site for the development of second cancer in females after primary cervical cancer. Glutathione S-transferase (GSTM1 and / or T1 null genotype modulates the risk of developing UADT cancer (primary as well as second cancer. The aim of this study was to evaluate the difference in GST null genotype frequencies in females with paired cancers in the UADT and genital region as compared to females with paired cancers in the UADT and non-genital region. Forty-nine females with a cancer in the UADT and another cancer (at all sites-genital and non-genital were identified from a database of patients with multiple primary neoplasms and were analyzed for the GSTM1 and T1 genotype in addition to known factors such as age, tobacco habits, alcohol habits and family history of cancer. Frequencies of GSTM1 null, GSTT1 null, and either GSTM1/T1 null were higher in females with paired occurrence of cancer in the UADT and genital site (54%, 33% and 75% respectively in comparison to females with paired occurrence of cancer in the UADT and non-genital sites (22%, 6% and 24% respectively. The significantly higher inherited frequency of either GSTM1/T1 null genotype in females with a paired occurrence of cancers in UADT and genital region (p = 0.01, suggests that these females are more susceptible to damage by carcinogens as compared to females who have UADT cancers in association with cancers at non-genital sites.

The calculation of oscillator strengths for the 5s21S0→5s5p1,3P1 transitions in Cd-like ions

International Nuclear Information System (INIS)

Li Guangyuan

1998-01-01

The screened hydrogenic model is employed to calculate the oscillator strength of the 5s 2 1 S 0 -5s5p 1 P 1 resonance transition in Cd-like ions (Z = 48 -74). The expression for the oscillator strength of the 5s 2 1 S 0 -5s5p 3 P1 is given, with the introduction of the correctional coefficient K and the mixing angle in jj-coupling. The results are compared with that of other authors, and some discussions are also given

HDL activation of endothelial sphingosine-1-phosphate receptor-1 (S1P1) promotes regeneration and suppresses fibrosis in the liver.

Science.gov (United States)

Ding, Bi-Sen; Liu, Catherine H; Sun, Yue; Chen, Yutian; Swendeman, Steven L; Jung, Bongnam; Chavez, Deebly; Cao, Zhongwei; Christoffersen, Christina; Nielsen, Lars Bo; Schwab, Susan R; Rafii, Shahin; Hla, Timothy

2016-12-22

Regeneration of hepatic sinusoidal vasculature is essential for non-fibrotic liver regrowth and restoration of its metabolic capacity. However, little is known about how this specialized vascular niche is regenerated. Here we show that activation of endothelial sphingosine-1-phosphate receptor-1 (S1P 1 ) by its natural ligand bound to HDL (HDL-S1P) induces liver regeneration and curtails fibrosis. In mice lacking HDL-S1P, liver regeneration after partial hepatectomy was impeded and associated with aberrant vascular remodeling, thrombosis and peri-sinusoidal fibrosis. Notably, this "maladaptive repair" phenotype was recapitulated in mice that lack S1P 1 in the endothelium. Reciprocally, enhanced plasma levels of HDL-S1P or administration of SEW2871, a pharmacological agonist specific for S1P 1 enhanced regeneration of metabolically functional vasculature and alleviated fibrosis in mouse chronic injury and cholestasis models. This study shows that natural and pharmacological ligands modulate endothelial S1P 1 to stimulate liver regeneration and inhibit fibrosis, suggesting that activation of this pathway may be a novel therapeutic strategy for liver fibrosis.

Sphingosine-1-phosphate promotes extravillous trophoblast cell invasion by activating MEK/ERK/MMP-2 signaling pathways via S1P/S1PR1 axis activation.

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Yang, Weiwei; Li, Qinghua; Pan, Zhifang

2014-01-01

Successful placentation depends on the proper invasion of extravillous trophoblast (EVT) cells into maternal tissues. Previous reports demonstrated that S1P receptors are expressed in the EVT cells and S1P could regulate migration and function of trophoblast cells via S1P receptors. However, little is known about roles of S1P in the invasion of EVT cells. Our study was performed to investigate S1P effect on the invasion of EVT cells. We used the extravillous trophoblast cell line HTR8/SVneo cells to evaluate the effect. In vitro invasion assay was employed to determine the invasion of HTR8/SVneo cells induced by S1P. MMP-2 enzyme activity and relative level in the supernatants of HTR8/SVneo was assessed by gelatin zymography and western blot. Based on the above, siRNA and specific inhibitors were used for the intervention and study of potential signal pathways, and Real-time qPCR and western blot were used to test the mRNA and protein level of potential signal targets. We found that S1P could promote HTR8/SVneo cell invasion and upregulates activity and level of MMP-2. The promotion requires activation of MEK-ERK and is dependent on the axis of S1P/S1PR1. Our investigation of S1P may provide new insights into the molecular mechanisms of EVT invasion.

Transgenic alfalfa plants co-expressing glutathione S-transferase (GST) and human CYP2E1 show enhanced resistance to mixed contaminates of heavy metals and organic pollutants

International Nuclear Information System (INIS)

Zhang, Yuanyuan; Liu, Junhong

2011-01-01

Transgenic alfalfa plants simultaneously expressing human CYP2E1 and glutathione S-transferase (GST) were generated from hypocotyl segments by the use of an Agrobacterium transformation system for the phytoremediation of the mixed contaminated soil with heavy metals and organic pollutants. The transgenic alfalfa plants were screened by a combination of kanamycin resistance, PCR, GST and CYP2E1 activity and Western blot analysis. The capabilities of mixed contaminants (heavy metals-organic compounds) resistance of pKHCG transgenic alfalfa plants became markedly increased compared with the transgenic alfalfa plants expressing single gene (GST or CYP2E1) and the non-transgenic control plants. The pKHCG alfalfa plants exhibited strong resistance towards the mixtures of cadmium (Cd) and trichloroethylene (TCE) that were metabolized by the introduced GST and CYP2E1 in combination. Our results show that the pKHCG transgenic alfalfa plants have good potential for phytoremediation because they have cross-tolerance towards the complex contaminants of heavy metals and organic pollutants. Therefore, these transgenic alfalfa plants co-expressing GST and human P450 CDNAs may have a great potential for phytoremediation of mixed environmental contaminants.

Transgenic alfalfa plants co-expressing glutathione S-transferase (GST) and human CYP2E1 show enhanced resistance to mixed contaminates of heavy metals and organic pollutants

Energy Technology Data Exchange (ETDEWEB)

Zhang, Yuanyuan [Department of Pharmaceutics, Qingdao University of Science and Technology, 53 Zhengzhou Road, P.O. Box 70, Qingdao 266042 (China); Liu, Junhong, E-mail: liujh@qust.edu.cn [Department of Pharmaceutics, Qingdao University of Science and Technology, 53 Zhengzhou Road, P.O. Box 70, Qingdao 266042 (China)

2011-05-15

Transgenic alfalfa plants simultaneously expressing human CYP2E1 and glutathione S-transferase (GST) were generated from hypocotyl segments by the use of an Agrobacterium transformation system for the phytoremediation of the mixed contaminated soil with heavy metals and organic pollutants. The transgenic alfalfa plants were screened by a combination of kanamycin resistance, PCR, GST and CYP2E1 activity and Western blot analysis. The capabilities of mixed contaminants (heavy metals-organic compounds) resistance of pKHCG transgenic alfalfa plants became markedly increased compared with the transgenic alfalfa plants expressing single gene (GST or CYP2E1) and the non-transgenic control plants. The pKHCG alfalfa plants exhibited strong resistance towards the mixtures of cadmium (Cd) and trichloroethylene (TCE) that were metabolized by the introduced GST and CYP2E1 in combination. Our results show that the pKHCG transgenic alfalfa plants have good potential for phytoremediation because they have cross-tolerance towards the complex contaminants of heavy metals and organic pollutants. Therefore, these transgenic alfalfa plants co-expressing GST and human P450 CDNAs may have a great potential for phytoremediation of mixed environmental contaminants.

Exit Strategies: S1P Signaling and T Cell Migration.

Science.gov (United States)

Baeyens, Audrey; Fang, Victoria; Chen, Cynthia; Schwab, Susan R

2015-12-01

Whereas the role of sphingosine 1-phosphate receptor 1 (S1PR1) in T cell egress and the regulation of S1P gradients between lymphoid organs and circulatory fluids in homeostasis are increasingly well understood, much remains to be learned about S1P signaling and distribution during an immune response. Recent data suggest that the role of S1PR1 in directing cells from tissues into circulatory fluids is reprised again and again, particularly in guiding activated T cells from non-lymphoid tissues into lymphatics. Conversely, S1P receptor 2 (S1PR2), which antagonizes migration towards chemokines, confines cells within tissues. Here we review the current understanding of the roles of S1P signaling in activated T cell migration. In this context, we outline open questions, particularly regarding the shape of S1P gradients in different tissues in homeostasis and inflammation, and discuss recent strategies to measure S1P. Copyright © 2015 Elsevier Ltd. All rights reserved.

Shaping the landscape: Metabolic regulation of S1P gradients

Science.gov (United States)

Olivera, Ana; Allende, Maria Laura; Proia, Richard L.

2012-01-01

Sphingosine-1-phosphate (S1P) is a lipid that functions as a metabolic intermediate and a cellular signaling molecule. These roles are integrated when compartments with differing extracellular S1P concentrations are formed that serve to regulate functions within the immune and vascular systems, as well as during pathologic conditions. Gradients of S1P concentration are achieved by the organization of cells with specialized expression of S1P metabolic pathways within tissues. S1P concentration gradients underpin the ability of S1P signaling to regulate in vivo physiology. This review will discuss the mechanisms that are necessary for the formation and maintenance of S1P gradients, with the aim of understanding how a simple lipid controls complex physiology. PMID:22735358

Only Acyl Carrier Protein 1 (AcpP1 Functions in Pseudomonas aeruginosa Fatty Acid Synthesis

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Jin-Cheng Ma

2017-11-01

Full Text Available The genome of Pseudomonas aeruginosa contains three open reading frames, PA2966, PA1869, and PA3334, which encode putative acyl carrier proteins, AcpP1, AcpP2, and AcpP3, respectively. In this study, we found that, although these apo-ACPs were successfully phosphopantetheinylated by P. aeruginosa phosphopantetheinyl transferase (PcpS and all holo-forms of these proteins could be acylated by Vibrio harveyi acyl-ACP synthetase (AasS, only AcpP1 could be used as a substrate for the synthesis of fatty acids, catalyzed by P. aeruginosa cell free extracts in vitro, and only acpP1 gene could restore growth in the Escherichia coliacpP mutant strain CY1877. And P. aeruginosaacpP1 could not be deleted, while disruption of acpP2 or acpP3 in the P. aeruginosa genome allowed mutant strains to grow as well as the wild type strain. These findings confirmed that only P. aeruginosa AcpP1 functions in fatty acid biosynthesis, and that acpP2 and acpP3 do not play roles in the fatty acid synthetic pathway. Moreover, disruption of acpP2 and acpP3 did not affect the ability of P. aeruginosa to produce N-acylhomoserine lactones (AHL, but replacement of P. aeruginosaacpP1 with E. coliacpP caused P. aeruginosa to reduce the production of AHL molecules, which indicated that neither P. aeruginosa AcpP2 nor AcpP3 can act as a substrate for synthesis of AHL molecules in vivo. Furthermore, replacement of acpP1 with E. coliacpP reduced the ability of P. aeruginosa to produce some exo-products and abolished swarming motility in P. aeruginosa.

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

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

2011-01-01

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

The role of sphingosine-1-phosphate (S1P) and ceramide-1-phosphate (C1P) in the trafficking of normal and malignant cells

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Ratajczak, Mariusz Z.; Suszynska, Malwina; Borkowska, Sylwia; Ratajczak, Janina; Schneider, Gabriela

2014-01-01

Introduction A common feature of many types of cells is their responsiveness to chemotactic gradients of factors for which they express the corresponding receptors. The most studied chemoattractants so far are peptide-based growth factors and a family of cytokines endowed with strong chemotactic properties, called chemokines. However, additional evidence has accumulated that, in addition to these peptide-based chemoattractants, an important role in cell migration is played by bioactive lipids. Areas covered Solid evidence has accumulated that two bioactive phosphorylated sphingolipids that are derivatives of sphingolipid metabolism, namely sphingosine-1-phosphate (S1P) and ceramide-1-phosphate (C1P), are potent chemoattractants for a variety of cells. In this review, we will discuss the effect of these two phosphorylated sphingolipids on the trafficking of normal and malignant cells, and, in particular, we will focus on their role in trafficking of normal hematopoietic stem/progenitor cells. Unlike other mediators, S1P under steady state conditions maintain a steep gradient between interstitial fluid and peripheral blood and lymph across the endothelial barrier, which is important in the egress of cells from bone marrow. Both S1P and C1P may be upregulated in damaged tissues, which may result in reversal of this gradient. Expert opinion S1P and C1P are important regulators of the trafficking of normal and malignant cells, and modification of their biological effects will have important applications in optimizing stem cell mobilization and homing, tissue organ/regeneration, and preventing cancer metastasis. PMID:24188167

Aberrant expression of the S1P regulating enzymes, SPHK1 and SGPL1, contributes to a migratory phenotype in OSCC mediated through S1PR2.

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Patmanathan, Sathya Narayanan; Johnson, Steven P; Lai, Sook Ling; Panja Bernam, Suthashini; Lopes, Victor; Wei, Wenbin; Ibrahim, Maha Hafez; Torta, Federico; Narayanaswamy, Pradeep; Wenk, Markus R; Herr, Deron R; Murray, Paul G; Yap, Lee Fah; Paterson, Ian C

2016-05-10

Oral squamous cell carcinoma (OSCC) is a lethal disease with a 5-year mortality rate of around 50%. Molecular targeted therapies are not in routine use and novel therapeutic targets are required. Our previous microarray data indicated sphingosine 1-phosphate (S1P) metabolism and signalling was deregulated in OSCC. In this study, we have investigated the contribution of S1P signalling to the pathogenesis of OSCC. We show that the expression of the two major enzymes that regulate S1P levels were altered in OSCC: SPHK1 was significantly upregulated in OSCC tissues compared to normal oral mucosa and low levels of SGPL1 mRNA correlated with a worse overall survival. In in vitro studies, S1P enhanced the migration/invasion of OSCC cells and attenuated cisplatin-induced death. We also demonstrate that S1P receptor expression is deregulated in primary OSCCs and that S1PR2 is over-expressed in a subset of tumours, which in part mediates S1P-induced migration of OSCC cells. Lastly, we demonstrate that FTY720 induced significantly more apoptosis in OSCC cells compared to non-malignant cells and that FTY720 acted synergistically with cisplatin to induce cell death. Taken together, our data show that S1P signalling promotes tumour aggressiveness in OSCC and identify S1P signalling as a potential therapeutic target.

Determination of the 1s2{\\ell }2{{\\ell }}^{\\prime } state production ratios {{}^{4}P}^{o}/{}^{2}P, {}^{2}D/{}^{2}P and {{}^{2}P}_{+}/{{}^{2}P}_{-} from fast (1{s}^{2},1s2s\\,{}^{3}S) mixed-state He-like ion beams in collisions with H2 targets