Reversible skeletal abnormalities in gamma-glutamyl transpeptidase-deficient mice

NASA Technical Reports Server (NTRS)

Levasseur, Regis; Barrios, Roberto; Elefteriou, Florent; Glass, Donald A 2nd; Lieberman, Michael W.; Karsenty, Gerard

2003-01-01

Gamma-glutamyl transpeptidase (GGT) is a widely distributed ectopeptidase responsible for the degradation of glutathione in the gamma-glutamyl cycle. This cycle is implicated in the metabolism of cysteine, and absence of GGT causes a severe intracellular decrease in this amino acid. GGT-deficient (GGT-/-) mice have multiple metabolic abnormalities and are dwarf. We show here that this latter phenotype is due to a decreased of the growth plate cartilage total height resulting from a proliferative defect of chondrocytes. In addition, analysis of vertebrae and tibiae of GGT-/- mice revealed a severe osteopenia. Histomorphometric studies showed that this low bone mass phenotype results from an increased osteoclast number and activity as well as from a marked decrease in osteoblast activity. Interestingly, neither osteoblasts, osteoclasts, nor chondrocytes express GGT, suggesting that the observed defects are secondary to other abnormalities. N-acetylcysteine supplementation has been shown to reverse the metabolic abnormalities of the GGT-/- mice and in particular to restore the level of IGF-1 and sex steroids in these mice. Consistent with these previous observations, N-acetylcysteine treatment of GGT-/- mice ameliorates their skeletal abnormalities by normalizing chondrocytes proliferation and osteoblastic function. In contrast, resorbtion parameters are only partially normalized in GGT-/- N-acetylcysteine-treated mice, suggesting that GGT regulates osteoclast biology at least partly independently of these hormones. These results establish the importance of cysteine metabolism for the regulation of bone remodeling and longitudinal growth.

Preclinical Evaluation of a Potential GSH Ester Based PET/SPECT Imaging Probe DT(GSHMe)₂ to Detect Gamma Glutamyl Transferase Over Expressing Tumors.

PubMed

Khurana, Harleen; Meena, Virendra Kumar; Prakash, Surbhi; Chuttani, Krishna; Chadha, Nidhi; Jaswal, Ambika; Dhawan, Devinder Kumar; Mishra, Anil Kumar; Hazari, Puja Panwar

2015-01-01

Gamma Glutamyl Transferase (GGT) is an important biomarker in malignant cancers. The redox processes ensuing from GGT-mediated metabolism of extracellular GSH are implicated in critical aspects of tumor cell biology. Reportedly, Glutathione monoethyl ester (GSHMe) is a substrate of GGT, which has been used for its rapid transport over glutathione. Exploring GGT to be an important target, a homobivalent peptide system, DT(GSHMe)2 was designed to target GGT-over expressing tumors for diagnostic purposes. DT(GSHMe)2 was synthesized, characterized and preclinically evaluated in vitro using toxicity, cell binding assays and time dependent experiments. Stable and defined radiochemistry with 99mTc and 68Ga was optimized for high radiochemical yield. In vivo biodistribution studies were conducted for different time points along with scintigraphic studies of radiolabeled DT(GSHMe)2 on xenografted tumor models. For further validation, in silico docking studies were performed on GGT (hGGT1, P19440). Preclinical in vitro evaluations on cell lines suggested minimal toxicity of DT(GSHMe)2 at 100 μM concentration. Kinetic analysis revealed transport of 99mTc-DT(GSHMe)2 occurs via a saturable high-affinity carrier with Michaelis constant (Km) of 2.25 μM and maximal transport rate velocity (Vmax) of 0.478 μM/min. Quantitative estimation of GGT expression from western blot experiments showed substantial expression with 41.6 ± 7.07 % IDV for tumor. Small animal micro PET (Positron Emission Tomography)/CT(Computed Tomography) coregistered images depicted significantly high uptake of DT(GSHMe)2 at the BMG-1 tumor site. ROI analysis showed high tumor to contra lateral muscle ratio of 9.33 in PET imaging studies. Avid accumulation of radiotracer was observed at tumor versus inflammation site at 2 h post i.v. injection in an Ehrlich Ascites tumor (EAT) mice model, showing evident specificity for tumor. We propose DT(GSHMe)2 to be an excellent candidate for prognostication and tumor

Distribution of gamma-glutamyl-beta-alanylhistidine isopeptide in the macromolecular fractions of commercial meat extracts and correlation with the color of the macromolecular fractions.

PubMed

Kuroda, Motonaka; Harada, Tsutomu

2002-03-27

The measurement of gamma-glutamyl-beta-alanylhistidine isopeptide in the macromolecular fraction of various commercial meat extracts indicated that all of the commercial meat extracts tested contained the isopeptide, in concentrations ranging from 0.04 to 0.87 micromol/g of dry matter. This variation was suggested to be due to the differences between the processes of extraction and the differences in the initial amounts of carnosine. A positive correlation between the content of gamma-glutamyl-beta-alanylhistidine and the color of the macromolecular fraction was observed. These results suggested that gamma-glutamyl-beta-alanylhistidine is widely distributed in meat products and that the content can be used as an index of protein denaturation during the heating process.

Serum Gamma-Glutamyl-Transferase Independently Predicts Outcome After Transarterial Chemoembolization of Hepatocellular Carcinoma: External Validation

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

Guiu, Boris, E-mail: boris.guiu@chu-dijon.fr; Deschamps, Frederic; Boulin, Mathieu

Purpose: An Asian study showed that gamma glutamyl transpeptidase (GGT) can predict survival after transarterial chemoembolization (TACE) of hepatocellular carcinoma (HCC). This study was designed to validate in a European population this biomarker as an independent predictor of outcome after TACE of HCC and to determine a threshold value for clinical use. Methods: In 88 consecutive patients treated by TACE for HCC, the optimal threshold for GGT serum level was determined by a ROC analysis. Endpoints were time-to-treatment failure (TTTF) and overall survival (OS). All multivariate models were internally validated using bootstrapping (90 replications). Results: Median follow-up lasted 373 days,more » and median overall survival was 748 days. The optimal threshold for GGT was 165 U/L (sensitivity: 89.3%; specificity: 56.7%; area under the ROC curve: 0.7515). Median TTTF was shorter when GGT was {>=}165 U/L (281 days vs. 850 days; P < 0.001). GGT {>=}165 U/L (hazard ratio (HR) = 2.06; P = 0.02), WHO PS of 2 (HR = 5.4; P = 0.002), and tumor size (HR = 1.12; P = 0.014) were independently associated with shorter TTTF. Median OS was shorter when GGT was {>=}165 U/L (508 days vs. not reached; P < 0.001). GGT {>=} 165 U/L (HR = 3.05; P = 0.029), WHO PS of 2 (HR = 12.95; P < 0.001), alfa-fetoprotein (HR = 2.9; P = 0.01), and tumor size (HR = 1.096; P = 0.013) were independently associated with shorter OS. The results were confirmed by bootstrapping. Conclusions: Our results provide in a European population the external validation of GGT as an independent predictor of outcome after TACE of HCC. A serum level of GGT {>=} 165 U/L is independently associated with both shorter TTTF and OS.« less

Glutamyl-gamma-boronate inhibitors of bacterial Glu-tRNA(Gln) amidotransferase.

PubMed

Decicco, C P; Nelson, D J; Luo, Y; Shen, L; Horiuchi, K Y; Amsler, K M; Foster, L A; Spitz, S M; Merrill, J J; Sizemore, C F; Rogers, K C; Copeland, R A; Harpel, M R

2001-09-17

Analogues of glutamyl-gamma-boronate (1) were synthesized as mechanism-based inhibitors of bacterial Glu-tRNA(Gln) amidotransferase (Glu-AdT) and were designed to engage a putative catalytic serine nucleophile required for the glutaminase activity of the enzyme. Although 1 provides potent enzyme inhibition, structure-activity studies revealed a narrow range of tolerated chemical changes that maintained activity. Nonetheless, growth inhibition of organisms that require Glu-AdT by the most potent enzyme inhibitors appears to validate mechanism-based inhibitor design of Glu-AdT as an approach to antimicrobial development.

Gamma glutamyl transferase is an independent determinant for the association of insulin resistance with nonalcoholic fatty liver disease in Bangladeshi adults: Association of GGT and HOMA-IR with NAFLD.

PubMed

Hossain, Israt Ara; Rahman Shah, Md Mijanur; Rahman, Mohammad Khalilur; Ali, Liaquat

2016-01-01

Nonalcoholic fatty liver disease (NAFLD) is a major cause of liver-related morbidity and is frequently associated with insulin resistance (HOMA-IR) syndrome. Recently serum gamma glutamyl transferase (GGT) has been considered as surrogate marker of NAFLD leading to oxidative stress and hepatocellular damage. In the present study we examined the association of serum GGT and HOMA-IR with NAFLD in Bangladeshi adult subjects. Under a cross-sectional analytical design a total of 110 subjects were recruited who came for their routine health check up in the BIHS Hospital, Darussalam, Dhaka, Bangladesh. After whole abdomen ultrasonography, 62 were diagnosed as non-NAFLD and 48 were NAFLD subjects. Serum glucose was measured by glucose-oxidase method, lipid profile and liver enzymes by enzymatic colorimetric method, glycosylated hemoglobin (HbA1c) was measured by high performance liquid chromatography (HPLC), serum insulin were measured by enzyme-linked immunosorbent assay. HOMA-IR was calculated by homeostasis model assessment (HOMA). NAFLD subjects had significantly higher levels of GGT and HOMA-IR as compared to their non-NAFLD counterparts. Multiple linear regression analysis showed a significant positive association of HOMA-IR with GGT after adjusting the effects of waist circumference (WC) and HbA1c. In binary logistic regression analysis, HOMA-IR and GGT were found to be significant determinants of NAFLD after adjusting the effects of WC and HbA1c. These results suggest that elevated levels of GGT and insulin resistance are more likely to develop NAFLD and thus support a role of these determinants in the pathogenesis of NAFLD in Bangladeshi adult subjects. Copyright © 2015 Diabetes India. Published by Elsevier Ltd. All rights reserved.

GGT (Gamma-Glutamyl Transferase) Test

MedlinePlus

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Relation of serum γ-glutamyl transferase activity with copper in an adult population.

PubMed

Peng, You-Fan; Wang, Chun-Fang; Pan, Guo-Gang

2017-10-26

The aim of this study was to evaluate the relationship between serum γ-glutamyl transferase (γ-GGT) activity and serum copper in an adult population. We analyzed 281 adult subjects who regularly attended the physical examination center at the Affiliated Hospital of Youjiang Medical University for Nationalities. The demographic and laboratory data of the participants were divided into two groups according to the median of serum γ-GGT activity. Serum copper concentrations in individuals with higher γ-GGT levels were significantly increased compared with those with lower γ-GGT concentrations (9.9±2.41 vs. 11.2±3.36 μmol/L, p<0.001). There was a positive correlation between serum γ-GGT activity and copper in all eligible subjects (r=0.198, p=0.001). Further, serum γ-GGT maintained a positive correlation with serum copper in both males and females (r=0.322, p<0.001; r=0.230, p=0.010). The results of multiple linear regression analysis showed that serum γ-GGT maintained a significantly positive correlation with copper after adjusting for multiple potential confounders (b=0.464, p=0.001). This study suggests that serum γ-GGT activity is correlated with copper in the study population, indicating that serum γ-GGT may be a biomarker to evaluate serum copper levels in an adult population.

Radiolabelling of isopeptide N epsilon-(gamma-glutamyl)-L-lysine by conjugation with N-succinimidyl-4-[18F]fluorobenzoate.

PubMed

Wüst, F; Hultsch, C; Bergmann, R; Johannsen, B; Henle, T

2003-07-01

The isopeptide N(epsilon)-(gamma-glutamyl)-L-lysine 4 was labelled with 18F via N-succinimidyl-4-[18F]fluorobenzoate ([18F]SFB). A modified approach for the convenient synthesis of [18F]SFB was used, and [18F]SFB could be obtained in decay-corrected radiochemical yields of 44-53% (n = 20) and radiochemical purity >95% within 40 min after EOB. For labelling N(epsilon)-(gamma-glutamyl)-L-lysine with [18F]SFB the effects of isopeptide concentration, temperature, and pH were studied to determine the optimum reaction conditions. The coupling reaction was shown to be temperature and pH independent while being strongly affected by the isopeptide concentration. Using the optimized labelling conditions, in a typical experiment 1.3GBq of [18F]SFB could be converted into 447MBq (46%, decay-corrected) of [18F]fluorobenzoylated isopeptide within 45 min, including HPLC purification.

Proteomic identification of Drosophila melanogaster male accessory gland proteins, including a pro-cathepsin and a soluble gamma-glutamyl transpeptidase.

PubMed

Walker, Michael J; Rylett, Caroline M; Keen, Jeff N; Audsley, Neil; Sajid, Mohammed; Shirras, Alan D; Isaac, R Elwyn

2006-05-02

In Drosophila melanogaster, the male seminal fluid contains proteins that are important for reproductive success. Many of these proteins are synthesised by the male accessory glands and are secreted into the accessory gland lumen, where they are stored until required. Previous studies on the identification of Drosophila accessory gland products have largely focused on characterisation of male-specific accessory gland cDNAs from D. melanogaster and, more recently, Drosophila simulans. In the present study, we have used a proteomics approach without any sex bias to identify proteins in D. melanogaster accessory gland secretions. Thirteen secreted accessory gland proteins, including seven new accessory gland proteins, were identified by 2D-gel electrophoresis combined with mass spectrometry of tryptic fragments. They included protein-folding and stress-response proteins, a hormone, a lipase, a serpin, a cysteine-rich protein and two peptidases, a pro-enzyme form of a cathepsin K-like cysteine peptidase and a gamma-glutamyl transpeptidase. Enzymatic studies established that accessory gland secretions contain a cysteine peptidase zymogen that can be activated at low pH. This peptidase may have a role in the processing of female and other male-derived proteins, but is unlikely to be involved in the processing of the sex peptide. gamma-Glutamyl transpeptidases are type II integral membrane proteins; however, the identified AG gamma-glutamyl transpeptidase (GGT-1) is unusual in that it is predicted to be a soluble secreted protein, a prediction that is supported by biochemical evidence. GGT-1 is possibly involved in maintaining a protective redox environment for sperm. The strong gamma-glutamyl transpeptidase activity found in the secretions provides an explanation for the observation that glutamic acid is the most abundant free amino acid in accessory gland secretions of D. melanogaster. We have applied biochemical approaches, not used previously, to characterise

Amniotic fluid gamma-glutamyl transpeptidase activity during the second trimester.

PubMed

Legge, M; Potter, H C

1986-03-12

Gamma glutamyl transpeptidase (GGTP) activity was determined in second trimester amniotic fluid taken from normal fetuses and those with fetal abnormalities. GGTP activity decreased with advancing gestation. Increasing meconium contamination correlated with an increase in GGTP activity as did increasing fetal blood contamination. Maternal blood did not affect GGTP activity. Anencephaly did not significantly alter the GGTP activity, however, fetuses with spina bifida had significantly lower activity. Klinefelters and Turners syndromes both had GGTP activity close to the 50th percentile, and two trisomy 21 fetuses had GGTP activity below the 40th percentile. Two trisomy 18 fetuses and two translocation Downs syndromes (46 XY, t (14;21) had GGTP activities considerably lower than the 20th percentile as did a fetus with gastroschisis. Second trimester amniotic fluid GGTP activity may provide an easy preliminary test to screen amniotic fluids for the possibility of certain fetal chromosome abnormalities.

Successful synthesis of active human coagulation factor VII by co-expression of mammalian gamma-glutamyl carboxylase and modification of vit.K cycle in Drosophila Schneider S2 cells.

PubMed

Nagahashi, Kotomi; Umemura, Kazuo; Kanayama, Naohiro; Iwaki, Takayuki

2017-04-01

Mammalian gamma-glutamyl carboxylase and reduced vitamin K are indispensable for synthesis of mature mammalian vitamin K dependent proteins including some of blood coagulation factors (factors II, VII, IX, and X). It was well known that Drosophila melanogaster expressed gamma-glutamyl carboxylase and possessed a vit.K cycle although native substrates for them have not been identified yet. Despite the potential capability of gamma carboxylation in D. melanogaster derived cells such as S2 cells, Drosophila gamma-glutamyl carboxylase failed to gamma carboxylate a peptide fused to the human coagulation factor IX propeptide. Thus, it had been believed that the Drosophila system was not adequate to synthesize mammalian vit.K dependent proteins. Indeed, we previously attempted to synthesize biologically active factor VII in S2 cells although we were not able to obtain it. However, recently, a successful transient expression of biologically active human factor IX from S2 cells was reported. In the present study, several expression vectors which enable expressing mammalian GGCX, VKORC1, and/or PDIA2 along with F7 were developed. S2 cells transfected with pMKA85, pMAK86, and pMAK219 successfully synthesized active FVII. Thus, mammalian GGCX was indispensable to synthesize active FVII while mammalian VKORC1 and PDIA2 were not critical but supportive factors for S2 cells.

The postoperative course of gamma-glutamyl transpeptidase--a marker of cytomegalovirus (CMV) replication risk?

PubMed

Schenk, M; Zipfel, A; Kratt, T; Petersen, P; Becker, H D; Viebahn, R

2000-11-01

Cytomegalovirus (CMV) infection is a common complication in the postoperative course of liver transplantation. In order to start early prophylactic therapy, but to avoid unnecessary treatment, or expensive screening, a desirable goal in post-transplant monitoring is to find appropriate markers in standard laboratory diagnostics. In the present study, the results of a 6-week CMV replication monitoring schedule by the pp65 antigenemia assay in 100 liver graft recipients were included. The activities of transaminases, glutamate dehydrogenase and gamma-glutamyl transpeptidase (gamma-GT) were measured by routine laboratory methods. In contrast to the transaminases, the serum activity of gamma-GT increased during the first postoperative week. The maximum levels were 246 +/- 211 U/l in patients without (n = 46) and 140 +/- 89 U/l in patients with early CMV replication (n = 54; p = 0.02). Patients with gamma-GT levels below 200 U/l on the 5th postoperative day (n = 72) had a CMV replication risk of 65%, whereas those patients with gamma-GT levels above this threshold had a risk of 30% (n = 28; p = 0.0007; relative risk = 2.9). These findings provide a routinely usable marker for the identification of patients at an increased risk of CMV replication. It can be considered that these phenomena may be caused by an additional immunosuppressive effect of the CMV virus.

γ-Glutamyl transferase 7 is a novel regulator of glioblastoma growth.

PubMed

Bui, Timothy T; Nitta, Ryan T; Kahn, Suzana A; Razavi, Seyed-Mostafa; Agarwal, Maya; Aujla, Parvir; Gholamin, Sharareh; Recht, Lawrence; Li, Gordon

2015-04-07

Glioblastoma (GBM) is the most malignant primary brain tumor in adults, with a median survival time of one and a half years. Traditional treatments, including radiation, chemotherapy, and surgery, are not curative, making it imperative to find more effective treatments for this lethal disease. γ-Glutamyl transferase (GGT) is a family of enzymes that was shown to control crucial redox-sensitive functions and to regulate the balance between proliferation and apoptosis. GGT7 is a novel GGT family member that is highly expressed in brain and was previously shown to have decreased expression in gliomas. Since other members of the GGT family were found to be altered in a variety of cancers, we hypothesized that GGT7 could regulate GBM growth and formation. To determine if GGT7 is involved in GBM tumorigenesis, we modulated GGT7 expression in two GBM cell lines (U87-MG and U138) and monitored changes in tumorigenicity in vitro and in vivo. We demonstrated for the first time that GBM patients with low GGT7 expression had a worse prognosis and that 87% (7/8) of primary GBM tissue samples showed a 2-fold decrease in GGT7 expression compared to normal brain samples. Exogenous expression of GGT7 resulted in a 2- to 3-fold reduction in proliferation and anchorage-independent growth under minimal growth conditions (1% serum). Decreasing GGT7 expression using either short interfering RNA or short hairpin RNA consistently increased proliferation 1.5- to 2-fold. In addition, intracranial injections of U87-MG cells with reduced GGT7 expression increased tumor growth in mice approximately 2-fold, and decreased mouse survival. To elucidate the mechanism by which GGT7 regulates GBM growth, we analyzed reactive oxygen species (ROS) levels in GBM cells with modulated GGT7 expression. We found that enhanced GGT7 expression reduced ROS levels by 11-33%. Our study demonstrates that GGT7 is a novel player in GBM growth and that GGT7 can play a critical role in tumorigenesis by regulating

Seed storage protein deficiency improves sulfur amino acid content in common bean (Phaseolus vulgaris L.): redirection of sulfur from gamma-glutamyl-S-methyl-cysteine.

PubMed

Taylor, Meghan; Chapman, Ralph; Beyaert, Ronald; Hernández-Sebastià, Cinta; Marsolais, Frédéric

2008-07-23

The contents of sulfur amino acids in seeds of common bean ( Phaseolus vulgaris L.) are suboptimal for nutrition. They accumulate large amounts of a gamma-glutamyl dipeptide of S-methyl-cysteine, a nonprotein amino acid that cannot substitute for methionine or cysteine in the diet. Protein accumulation and amino acid composition were characterized in three genetically related lines integrating a progressive deficiency in major seed storage proteins, phaseolin, phytohemagglutinin, and arcelin. Nitrogen, carbon, and sulfur contents were comparable among the three lines. The contents of S-methyl-cysteine and gamma-glutamyl-S-methyl-cysteine were progressively reduced in the mutants. Sulfur was shifted predominantly to the protein cysteine pool, while total methionine was only slightly elevated. Methionine and cystine contents (mg per g protein) were increased by up to ca. 40%, to levels slightly above FAO guidelines on amino acid requirements for human nutrition. These findings may be useful to improve the nutritional quality of common bean.

Identification of the mpl gene encoding UDP-N-acetylmuramate: L-alanyl-gamma-D-glutamyl-meso-diaminopimelate ligase in Escherichia coli and its role in recycling of cell wall peptidoglycan.

PubMed Central

Mengin-Lecreulx, D; van Heijenoort, J; Park, J T

1996-01-01

A gene, mpl, encoding UDP-N-acetylmuramate:L-alanyl-gamma-D-glutamyl-meso-diaminopimelat e ligase was recognized by its amino acid sequence homology with murC as the open reading frame yjfG present at 96 min on the Escherichia coli map. The existence of such an enzymatic activity was predicted from studies indicating that reutilization of the intact tripeptide L-alanyl-gamma-D-glutamyl-meso-diaminopimelate occurred and accounted for well over 30% of new cell wall synthesis. Murein tripeptide ligase activity could be demonstrated in crude extracts, and greatly increased activity was produced when the gene was cloned and expressed under control of the trc promoter. A null mutant totally lacked activity but was viable, showing that the enzyme is not essential for growth. PMID:8808921

Liver enzymes in patients with chronic kidney disease undergoing peritoneal dialysis and hemodialysis.

PubMed

Liberato, Isabella Ramos de Oliveira; Lopes, Edmundo Pessoa de Almeida; Cavalcante, Maria Alina Gomes de Mattos; Pinto, Tiago Costa; Moura, Izolda Fernades; Loureiro Júnior, Luiz

2012-01-01

The present study was designed to analyze the serum levels of aspartate and alanine aminotransferases, gamma-glutamyl transferase, and the hematocrit in patients with chronic kidney disease who were undergoing peritoneal dialysis or hemodialysis. Twenty patients on peritoneal dialysis and 40 on hemodialysis were assessed, and the patients were matched according to the length of time that they had been on dialysis. Blood samples were collected (both before and after the session for those on hemodialysis) to measure the enzymes and the hematocrit. In the samples from the patients who were undergoing peritoneal dialysis, the aspartate and alanine aminotransferase levels were slightly higher compared with the samples collected from the patients before the hemodialysis session and slightly lower compared with the samples collected after the hemodialysis session. The levels of gamma-glutamyl transferase in the hemodialysis patients were slightly higher than the levels in the patients who were undergoing peritoneal dialysis. In addition, the levels of aminotransferases and gamma-glutamyl transferase that were collected before the hemodialysis session were significantly lower than the values collected after the session. The hematocrit levels were significantly lower in the patients who were on peritoneal dialysis compared with the patients on hemodialysis (both before and after the hemodialysis session), and the levels were also significantly lower before hemodialysis compared with after hemodialysis. The aminotransferase levels in the patients who were undergoing peritoneal dialysis were slightly higher compared with the samples collected before the hemodialysis session, whereas the aminotransferase levels were slightly lower compared with the samples collected after the session. The hematocrits and the aminotransferase and gamma-glutamyl transferase levels of the samples collected after the hemodialysis session were significantly higher than the samples collected before

Elevated fasting glucose and albuminuria may be a marker for all-cause mortality in Indigenous adults in North Queensland - a follow up study, 1998-2006.

PubMed

Li, Ming; McDermott, Robyn

2017-04-01

To document risk factors of all-cause mortality in a cohort of indigenous Australians from 23 communities of North Queensland during 1998-2006. Among 2787 indigenous adults, baseline weight, waist circumference, blood pressure, fasting glucose, lipids, gamma-glutamyl transferase, urine albumin creatinine ratio, smoking, alcohol intake and physical activity were measured in 1998-2000. Deaths were ascertained from State Registry of Deaths, hospitalization and clinical records till 2006. Mortality risk factors were assessed using a Cox proportional-hazards model. The standardized all-cause mortality rate was 23.2/1000 person-years (95% CI 20.3-26.3/1000 pys). After adjusting for age, sex, and ethnicity, baseline plasm fasting glucose >=5.5mmol/L was associated with a 50% increased risk of death (HR 1.5, 95% CI 1.2-2.0). Albuminuria was associated with all-cause mortality with a hazards ratio of 1.4 for microalbuminuria (95% CI 1.0-1.9) and 2.6 (95% CI 1.8-3.7) for macroalbuminuria. Gamma-glutamyl transferase >=50IU was associated with an increased risk of all-cause mortality by 40% (95% CI 1.04-1.8). Fasting glycaemia, albuminuria, and gamma-glutamyl transferase, may be a marker for all-cause mortality within this cohort. Copyright © 2017 Elsevier Inc. All rights reserved.

Structure of 6-diazo-5-oxo-norleucine-bound human gamma-glutamyl transpeptidase 1, a novel mechanism of inactivation.

PubMed

Terzyan, Simon S; Cook, Paul F; Heroux, Annie; Hanigan, Marie H

2017-06-01

Intense efforts are underway to identify inhibitors of the enzyme gamma-glutamyl transpeptidase 1 (GGT1) which cleaves extracellular gamma-glutamyl compounds and contributes to the pathology of asthma, reperfusion injury and cancer. The glutamate analog, 6-diazo-5-oxo-norleucine (DON), inhibits GGT1. DON also inhibits many essential glutamine metabolizing enzymes rendering it too toxic for use in the clinic as a GGT1 inhibitor. We investigated the molecular mechanism of human GGT1 (hGGT1) inhibition by DON to determine possible strategies for increasing its specificity for hGGT1. DON is an irreversible inhibitor of hGGT1. The second order rate constant of inactivation was 0.052 mM -1 min -1 and the K i was 2.7 ± 0.7 mM. The crystal structure of DON-inactivated hGGT1 contained a molecule of DON without the diazo-nitrogen atoms in the active site. The overall structure of the hGGT1-DON complex resembled the structure of the apo-enzyme; however, shifts were detected in the loop forming the oxyanion hole and elements of the main chain that form the entrance to the active site. The structure of hGGT1-DON complex revealed two covalent bonds between the enzyme and inhibitor which were part of a six membered ring. The ring included the OG atom of Thr381, the reactive nucleophile of hGGT1 and the α-amine of Thr381. The structure of DON-bound hGGT1 has led to the discovery of a new mechanism of inactivation by DON that differs from its inactivation of other glutamine metabolizing enzymes, and insight into the activation of the catalytic nucleophile that initiates the hGGT1 reaction. © 2017 The Protein Society.

Gamma-glutamyl transpeptidase to cholinesterase and platelet ratio in predicting significant liver fibrosis and cirrhosis of chronic hepatitis B.

PubMed

Liu, Danping; Li, Jian; Lu, Wei; Wang, Yanbing; Zhou, Xinlan; Huang, Dan; Li, Xiufen; Ding, Rongrong; Zhang, Zhanqing

2018-06-12

To evaluate the performance of a new mathematical model gamma- glutamyl transpeptidase to cholinesterase and platelet ratio (GCPR) versus gamma- glutamyl transpeptidase to platelet ratio (GPR) in predicting significant fibrosis and cirrhosis of chronic hepatitis B (CHB). A complete cohort of 2343 patients was divided into early and late cohort depending on the time of liver biopsy. With reference to the Scheuer standard, liver pathological stage ≥S2 and ≥S4 were defined as significant fibrosis and cirrhosis, respectively. ROC curve was used to evaluate the performance of investigated models. In early cohort，the areas under ROC curves (AUROCs) of GCPR in predicting significant fibrosis of HBeAg-positive and HBeAg-negative patients (0.782 and 0.775) were both significantly greater than those of GPR (0.748 and 0.747) (Z＝8.198 and Z＝6.023, both P<0.0001); the AUROCs of GCPR in predicting cirrhosis of HBeAg-positive and HBeAg-negative patients (0.842 and 0.861) were both significantly greater than those of GPR (0.802 and 0.823) (Z＝6.686 and Z＝6.116, both P<0.0001). In early, late and complete cohort, using a single cutoff of GPCR>0.080, the specificities of GCPR in predicting significant fibrosis of HBeAg-positive patients were 83.3%, 88.2% and 85.0%, and of HBeAg-negative patients were 87.6%, 87.4% and 87.6%, respectively; and the sensitivities of GCPR in predicting cirrhosis of HBeAg-positive patients were 81.9%, 88.7% and 84.2%, and of HBeAg-negative patients were 83.1%,82.1% and 82.7%, respectively. GCPR has higher performance than GPR in predicting significant fibrosis and cirrhosis of CHB. Copyright © 2018 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

Biochemical Effects on the Liver of 1 Month of Alcohol Abstinence in Moderate Alcohol Consumers.

PubMed

Munsterman, I D; Groefsema, M M; Weijers, G; Klein, W M; Swinkels, D W; Drenth, J P H; Schellekens, A F A; Tjwa, E T T L

2018-05-03

In this study in healthy moderate alcohol consumers, we observe that one month of alcohol abstinence results in decreased gamma-glutamyl transferase levels, which return to baseline levels after resumption of alcohol consumption.

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

PubMed

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

2009-02-01

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

Oxidative Stress as Estimated by Gamma-Glutamyl Transferase Levels Amplifies the Alkaline Phosphatase-Dependent Risk for Mortality in ESKD Patients on Dialysis

PubMed Central

Mattace-Raso, Francesco; van Saase, Jan L. C. M.; Postorino, Maurizio; Tripepi, Giovanni Luigi; Mallamaci, Francesca; PROGREDIRE Study Group

2016-01-01

Alkaline phosphatase (Alk-Phos) is a powerful predictor of death in patients with end-stage kidney disease (ESKD) and oxidative stress is a strong inducer of Alk-Phos in various tissues. We tested the hypothesis that oxidative stress, as estimated by a robust marker of systemic oxidative stress like γ-Glutamyl-Transpeptidase (GGT) levels, may interact with Alk-Phos in the high risk of death in a cohort of 993 ESKD patients maintained on chronic dialysis. In fully adjusted analyses the HR for mortality associated with Alk-Phos (50 IU/L increase) was progressively higher across GGT quintiles, being minimal in patients in the first quintile (HR: 0.89, 95% CI: 0.77–1.03) and highest in the GGT fifth quintile (HR: 1.13, 95% CI: 1.03–1.2) (P for the effect modification = 0.02). These findings were fully confirmed in sensitivity analyses excluding patients with preexisting liver disease, excessive alcohol intake, or altered liver disease biomarkers. GGT amplifies the risk of death associated with high Alk-Phos levels in ESKD patients. This observation is compatible with the hypothesis that oxidative stress is a strong modifier of the adverse biological effects of high Alk-Phos in this population. PMID:27525053

Use of urinary γ-glutamyl transferase (GGT) to monitor the pattern of proteinuria in dogs with leishmaniasis treated with N-methylglucamine antimoniate.

PubMed

Paltrinieri, Saverio; Mangiagalli, Giulia; Ibba, Fabrizio

2018-05-25

The aim of this study was to assess if the coupled analysis of the urinary protein to creatinine (UPC) ratio and of the GGT/UC ratio (the ratio between urinary γ-glutamyl transferase activity and urinary creatinine) may be used in treated leishmaniotic dogs to differentiate dogs with transient impairment of tubular function from dogs with persistent tubular damage. To this aim, 40 urine from 10 proteinuric and leishmaniotic dogs that at the first visit had high GGT/UC ratio, consistent with tubular damage, were collected and analyzed before treatments and 2, 4 and 6 weeks after treatment with N-methylglucamine antimoniate and allopurinol. Compared with pre-treatment values, at the end of the study period the UPC ratio decreased only in 5/10 dogs, which, however, were still proteinuric or borderline proteinuric. Conversely, the GGT/CU ratio decreased in 8/10 dogs and in 3 of them the values at the end of the study period were below the threshold consistent with tubular proteinuria. The GGT/UC values at 6 weeks was significantly lower than before treatment. However, transient increases were frequent for both the analytes. These results indicate that in most of the dogs that remain proteinuric after treatment, likely due to the persistent glomerular damage, the GGT/UC ratio tends to normalize. This suggests that in these dogs tubular proteinuria at admission depends on functional impairment of tubular cells likely due to the overflow of proteins from damaged glomeruli. However, tubular proteinuria occasionally persists, suggesting that tubulointerstitial damages persist even in dogs responsive to treatments. Copyright © 2018 Elsevier Ltd. All rights reserved.

Surrogate markers of the kidney and liver in the assessment of gestational diabetes mellitus and fetal outcome.

PubMed

Liu, Hong; Shao-Gang, Ma; Liang, Cheng; Feng, Bai; Wei, Xu

2015-01-01

To investigate whether serum levels of butyrylcho-linesterase activity, cystatin C, and pre-albumin has the potential value as γ-glutamyl transferase in reflecting gestational diabetes mellitus and its fetal outcome. Seventy-six gestational diabetes mellitus women and 76 pregnancies with normal glucose tolerance in the second trimester were enrolled. Maternal serum parameters of butyrylcholinesterase activity, γ-glutamyl transferase, cystatin C, and pre-albumin were detected and evaluated. The pregnant complications and fetal outcome were also evaluated. Levels of butyrylcholinesterase activity, γ-glutamyl transferase, cystatin C, pre-albumin and glycemic variables were higher in the gestational diabetes mellitus patients than in the controls. Levels of butyrylcholinesterase activity were significantly correlated to the levels of fasting plasma glucose, cystatin C, and γ- glutamyl transferase (p < 0.05) in the gestational diabetes mellitus group. There were statistical differences in cases of preterm delivery, preeclampsia and postpartum hemorrhage. Higher levels of γ-glutamyl transferase and pre-albumin were risk markers for gestational diabetes mellitus (p < 0.05). The diagnosis curve demonstrated that γ-glutamyl transferase had a significant advantage over other markers (p < 0.001) but no significance compared with pre-albumin (p = 0.096). None of the detected markers showed predictive value for fetal outcome. Serum levels of butyrylcholinesterase activity, γ-glutamyl transferase, cystatin C and pre-albumin were correlated with gestational diabetes mellitus status but not with the fetal outcome. Pre-albumin can be equivalent as γ-glutamyl transferase in reflecting the presence of gestational diabetes mellitus.

Structural control of caspase-generated glutamyl-tRNA synthetase by appended noncatalytic WHEP domains.

PubMed

Halawani, Dalia; Gogonea, Valentin; DiDonato, Joseph A; Pipich, Vitaliy; Yao, Peng; China, Arnab; Topbas, Celalettin; Vasu, Kommireddy; Arif, Abul; Hazen, Stanley L; Fox, Paul L

2018-06-08

Aminoacyl-tRNA synthetases are ubiquitous, evolutionarily conserved enzymes catalyzing the conjugation of amino acids onto cognate tRNAs. During eukaryotic evolution, tRNA synthetases have been the targets of persistent structural modifications. These modifications can be additive, as in the evolutionary acquisition of noncatalytic domains, or subtractive, as in the generation of truncated variants through regulated mechanisms such as proteolytic processing, alternative splicing, or coding region polyadenylation. A unique variant is the human glutamyl-prolyl-tRNA synthetase (EPRS) consisting of two fused synthetases joined by a linker containing three copies of the WHEP domain (termed by its presence in tryptophanyl-, histidyl-, and glutamyl-prolyl-tRNA synthetases). Here, we identify site-selective proteolysis as a mechanism that severs the linkage between the EPRS synthetases in vitro and in vivo Caspase action targeted Asp-929 in the third WHEP domain, thereby separating the two synthetases. Using a neoepitope antibody directed against the newly exposed C terminus, we demonstrate EPRS cleavage at Asp-929 in vitro and in vivo Biochemical and biophysical characterizations of the N-terminally generated EPRS proteoform containing the glutamyl-tRNA synthetase and most of the linker, including two WHEP domains, combined with structural analysis by small-angle neutron scattering, revealed a role for the WHEP domains in modulating conformations of the catalytic core and GSH- S -transferase-C-terminal-like (GST-C) domain. WHEP-driven conformational rearrangement altered GST-C domain interactions and conferred distinct oligomeric states in solution. Collectively, our results reveal long-range conformational changes imposed by the WHEP domains and illustrate how noncatalytic domains can modulate the global structure of tRNA synthetases in complex eukaryotic systems. © 2018 by The American Society for Biochemistry and Molecular Biology, Inc.

Regulatory aspects of the glutamylation of methotrexate in cultured hepatoma cells

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

Nimec, Z.; Galivan, J.

1983-10-15

The glutamylation of methotrexate has been evaluated in H35 hepatoma cells in vitro as a function of the conditions of culture. Glutamylation yields methotrexate polyglutamate with two to five additional glutamate residues and is a saturable process. The rate of glutamylation increases little above 10 microM extracellular methotrexate which corresponds to an intracellular concentration of approximately 4 microM. The rate of glutamylation measured over a 6-h period was stimulated by a reduction in cellular folates and prior incubation of the cells with insulin. Glutamylation was also more rapid in dividing cultures than in confluent cells. The combination of insulin inclusionmore » and folate reduction, which was additive, caused approximately a fourfold increase in the rate of glutamylation over control cells under the conditions tested. The maximal rate of methotrexate glutamylation, which was 100 nmol/g/h, occurred in folate-depleted, insulin-supplemented cells. Supplementing folate-depleted cells with reduced folate coenzymes caused the glutamylation to be reduced by more than 90%. In addition to showing that folates can modify the rates of methotrexate polyglutamate formation, data are presented suggesting that methotrexate polyglutamates can regulate their own synthesis. The consequences of the formation of these retained forms of methotrexate in H35 hepatoma cells and the effects of potential regulators of this process are discussed in terms of the glutamylation of folates in the cells and the chemotherapeutic effects of antifolates.« less

Caenorhabditis elegans glutamylating enzymes function redundantly in male mating.

PubMed

Chawla, Daniel G; Shah, Ruchi V; Barth, Zachary K; Lee, Jessica D; Badecker, Katherine E; Naik, Anar; Brewster, Megan M; Salmon, Timothy P; Peel, Nina

2016-09-15

Microtubule glutamylation is an important modulator of microtubule function and has been implicated in the regulation of centriole stability, neuronal outgrowth and cilia motility. Glutamylation of the microtubules is catalyzed by a family of tubulin tyrosine ligase-like (TTLL) enzymes. Analysis of individual TTLL enzymes has led to an understanding of their specific functions, but how activities of the TTLL enzymes are coordinated to spatially and temporally regulate glutamylation remains relatively unexplored. We have undertaken an analysis of the glutamylating TTLL enzymes in C. elegans We find that although all five TTLL enzymes are expressed in the embryo and adult worm, loss of individual enzymes does not perturb microtubule function in embryonic cell divisions. Moreover, normal dye-filling, osmotic avoidance and male mating behavior indicate the presence of functional amphid cilia and male-specific neurons. A ttll-4(tm3310); ttll-11(tm4059); ttll-5(tm3360) triple mutant, however, shows reduced male mating efficiency due to a defect in the response step, suggesting that these three enzymes function redundantly, and that glutamylation is required for proper function of the male-specific neurons. © 2016. Published by The Company of Biologists Ltd.

Pattern of γ-glutamyl transferase activity in cow milk throughout lactation and relationships with metabolic conditions and milk composition.

PubMed

Calamari, L; Gobbi, L; Russo, F; Cappelli, F Piccioli

2015-08-01

The main objective of this experiment was to study the γ-glutamyl transferase (GGT) activity in milk during lactation and its relationship with metabolic status of dairy cows, milk yield, milk composition, and cheesemaking properties. The study was performed in a tied stall barn and involved 20 lactations from 12 healthy multiparous Italian Friesian dairy cows. During lactation starting at d 10, milk samples were collected weekly and analyzed for composition, somatic cells count, titratable acidity, and milk coagulation properties. The GGT activity was measured in defatted samples. Blood samples were collected weekly to assess biochemical indicators related to energy, protein, and mineral metabolism, markers of inflammation and some enzyme activities. The lactations of each cow were retrospectively categorized into 2 groups according to their milk GGT activity value through lactation. A median value of GGT activity in the milk of all lactations was calculated (3,045 U/L), and 10 lactations with lower GGT activity were classified as low while 10 lactations with greater GGT activity were classified as high. The average value of milk GGT activity during lactation was 3,863 and 3,024 U/L for high and low, respectively. The GGT activity decreased in early lactation and reached minimum values in the second month (3,289 and 2,355 U/L for high and low, respectively). Thereafter GGT activity increased progressively, reaching values in late lactation of 4,511 and 3,540 U/L in high and low, respectively. On average, milk yield was 40.81 and 42.76 kg/d in high and low, respectively, and a negative partial correlation with milk GGT activity was observed. A greater milk protein concentration was observed in high (3.39%) compared with low (3.18%), and a positive partial correlation with milk GGT activity was observed. Greater titratable acidity in high than that in low (3.75 vs. 3.45 degrees Soxhlet-Henkel/50 mL, respectively) was also observed. Plasma glucose was greater in

Formation of Kokumi-Enhancing γ-Glutamyl Dipeptides in Parmesan Cheese by Means of γ-Glutamyltransferase Activity and Stable Isotope Double-Labeling Studies.

PubMed

Hillmann, Hedda; Behr, Jürgen; Ehrmann, Matthias A; Vogel, Rudi F; Hofmann, Thomas

2016-03-02

Recently, γ-glutamyl dipeptides (γ-GPs) were found to be responsible for the attractive kokumi flavor of Parmesan cheese (PC). Quantitation of γ-GPs and their parent amino acids in 13-, 24-, and 30-month ripened PC samples by LC-MS/MS and stable isotope dilution analysis (SIDA), in-cheese (13)C-labeling studies, followed by analysis of the γ-glutamyl transferase (GGT) activity revealed γ-GPs to be generated most efficiently after 24 months of ripening by a GGT-catalyzed transfer of the γ-glutamyl moiety of L-glutamine onto various acceptor amino acids released upon casein proteolysis. Following the identification of milk as a potential GGT source in PC, the functionality of the milk's GGT to generate the target γ-GPs was validated by stable isotope double-labeling (SIDL) experiments. Therefore, raw and heat-treated milk samples were incubated with L-glutamine-[U-(13)C] and acceptor amino acids (X) and the hetero- (γ-Glu-[(13)C5]-X) and homotranspeptidation products (γ-Glu-Gln-[(13)C10]) were quantitated by LC-MS/MS-SIDA using γ-Glu-Ala-[(13)C3] as the internal standard. High GGT activity to generate the γ-GPs and preference for L-phenylalanine and L-methionine as acceptor amino acids were found in raw milk and milk samples heat-treated for 10 min up to a maximum of 65 °C. In comparison, GGT activity and SIDL studies performed with inoculated Lactobacillus strains, including Lactobacillus harbinensis and Lactobacillus casei identified in PC by means of 16S rRNA gene sequencing, did not show any significant GGT activity and unequivocally demonstrated unpasteurized cow's milk, rather than microorganisms, as a key factor in γ-glutamyl dipeptide generation in Parmesan cheese.

Relationship between gamma-glutamyl transpeptidase activity and garlic greening, as controlled by temperature.

PubMed

Li, Lei; Hu, Dan; Jiang, Ying; Chen, Fang; Hu, Xiaosong; Zhao, Guanghua

2008-02-13

It was established that storage at low temperature (less than 10 degrees C) was required for garlic greening occurring either during processing or in the course of "Laba" garlic preparation while storage at high temperature (higher than 20 degrees C) inhibited its occurrence. However, the reason for this observation is unclear. To obtain insights into a tie connected between storage temperature and garlic greening, it was detected if the gamma-glutamyl transpeptidase (GGT) activity correlated with garlic greening because the activity of this enzyme is very sensitive to storage temperature. Results showed that garlic puree (which was prepared from fresh garlic) turned green upon addition of GGT but the color of garlic puree remained unchanged when either water or heat-treated GGT (which has no activity due to heat treatment) was used, a result giving a positive answer to the above proposal. Subsequently, to further clarify the relationship between the GGT activity and garlic greening, the GGT activity, the degree of garlic greening, and the concentration of total thiosulfinates in garlic bulbs were determined respectively after the garlic bulbs had been stored at 4 degrees C for up to 59 days followed by storage at 35 degrees C for up to 22 days. It was found that cold storage facilitated the GGT activity whereas warm storage inhibited the activity of this enzyme, just like the effect of storage temperature on greening, indicating that the increase of GGT activity could be a direct factor resulting in garlic greening. Consistent with this conclusion, the concentration of total thiosulfinates (the color developers) in garlic purees likewise exhibited a reversible change by moving garlic bulbs from one low storage temperature to a higher one; namely, it increased with increasing storage time during storage at 4 degrees C while decreasing as storage time increased during storage at 35 degrees C. The present study provided direct evidence that the GGT is involved in

A Survey of Glutamine Synthetase Activities in Tissues from Three Classes of Fish.

DTIC Science & Technology

1980-09-01

reveree side it necessay end identify by block enamaber) Glutamine synthetase, gamma-glutamyl transferase, osmoregulation , glutamate, glutamine...aspects of osmoregulation as well. The only known route of glutanmine synthesis n all species is activity of glutamine synthetase (EC 6.3.1.2) which...for osmoregulation . There is a relatively small difference n species which retain urea for osmoregulation . This may help to explain the relationship of

Enzyme activities in plasma, liver, and kidney of black ducks and mallards

USGS Publications Warehouse

Franson, J. Christian

1982-01-01

Activities of alanine aminotransferase (ALT), aspartate aminotransferase (AST), creatine phosphokinase (CPK), alkaline phosphatase (ALP), and lactate dehydrogenase (LDH) were measured in plasma, liver, and kidney, and gamma-glutamyl transferase (GGT) was measured in liver and kidney of black ducks (Anas rubripes). Activities of ALT, AST, GGT, and ornithine carbamyl transferase (OCT) were assayed in plasma, liver, and kidney of game-farm mallards (Anas platyrhynchos). Appreciable OCT and AST activity occurred in both liver and kidney. Activities of ALT, CPK, ALP and GGT were higher in kidney, while LDH was higher in liver, GGT was detected in plasma from one of four mallards.

Alcohol abuse and liver enzymes (AALE): results of an intercompany study of mortality.

PubMed

Titcomb, C; Braun, R; Roudebush, B; Mast, J; Woodman, H

2001-01-01

Evaluation of applicants for life insurance who have elevations of their liver function tests or an increased probability of alcohol abuse has always been difficult for underwriters. This paper reports the results of an intercompany study in which the pooled mortality experience of a group of insureds with evidence of alcohol abuse, an adverse driving record or elevations of the liver transaminases or gamma-glutamyl transferase is summarized.

Comparative genomics of duplicate γ-glutamyl transferase genes in teleosts: medaka (Oryzias latipes), stickleback (Gasterosteus aculeatus), green spotted pufferfish (Tetraodon nigroviridis), fugu (Takifugu rubripes), and zebrafish (Danio rerio).

PubMed

Law, Sheran Hiu Wan; Redelings, Benjamin David; Kullman, Seth William

2012-01-15

The availability of multiple teleost (bony fish) genomes is providing unprecedented opportunities to understand the diversity and function of gene duplication events using comparative genomics. Here we examine multiple paralogous genes of γ-glutamyl transferase (GGT) in several distantly related teleost species including medaka, stickleback, green spotted pufferfish, fugu, and zebrafish. Through mining genome databases, we have identified multiple GGT orthologs. Duplicate (paralogous) GGT sequences for GGT1 (GGT1 a and b), GGTL1 (GGTL1 a and b), and GGTL3 (GGTL3 a and b) were identified for each species. Phylogenetic analysis suggests that GGTs are ancient proteins conserved across most metazoan phyla and those paralogous GGTs in teleosts likely arose from the serial 3R genome duplication events. A third GGTL1 gene (GGTL1c) was found in green spotted pufferfish; however, this gene is not present in medaka, stickleback, or fugu. Similarly, one or both paralogs of GGTL3 appear to have been lost in green spotted pufferfish, fugu, and zebrafish. Syntenic relationships were highly maintained between duplicated teleost chromosomes, among teleosts and across ray-finned (Actinopterygii) and lobe-finned (Sarcopterygii) species. To assess subfunction partitioning, six medaka GGT genes were cloned and assessed for developmental and tissue-specific expression. On the basis of these data, we propose a modification of the "duplication-degeneration-complementation" model of subfunction partitioning where quantitative differences rather than absolute differences in gene expression are observed between gene paralogs. Our results demonstrate that multiple GGT genes have been retained within teleost genomes. Questions remain, however, regarding the functional roles of multiple GGTs in these species. Copyright © 2011 Wiley Periodicals, Inc., A Wiley Company.

Intervention of Dietary Dipeptide Gamma-l-Glutamyl-l-Valine (γ-EV) Ameliorates Inflammatory Response in a Mouse Model of LPS-Induced Sepsis.

PubMed

Chee, MacKenzie E; Majumder, Kaustav; Mine, Yoshinori

2017-07-26

Sepsis, the systemic inflammatory response syndrome (SIRS) with infection is one of the leading causes of death in critically ill patients in the developed world due to the lack of effective antisepsis treatments. This study examined the efficacy of dietary dipeptide gamma-l-glutamyl-l-valine (γ-EV), which was characterized previously as an anti-inflammatory peptide, in an LPS-induced mouse model of sepsis. BALB/c mice were administered γ-EV via oral gavage followed by an intraperitoneal injection of LPS to induce sepsis. The γ-EV exhibited antisepsis activity by reducing the expression of pro-inflammatory cytokines TNF-α, IL-6, and IL-1β in plasma and small intestine. γ-EV also reduced the phosphorylation of the signaling proteins JNK and IκBα. We concluded that γ-EV could possess an antisepsis effect against bacterial infection in intestine. This study proposes a signaling mechanism whereby the calcium-sensing receptor (CaSR) allosterically activated by γ-EV stimulates the interaction of β-arrestin2 with the TIR(TLR/IL-1R) signaling proteins TRAF6, TAB1, and IκBα to suppress inflammatory signaling.

Structural analysis and taste evaluation of γ-glutamyl peptides comprising sulfur-containing amino acids.

PubMed

Amino, Yusuke; Wakabayashi, Hidehiko; Akashi, Satoko; Ishiwatari, Yutaka

2018-03-01

The structures, flavor-modifying effects, and CaSR activities of γ-glutamyl peptides comprising sulfur-containing amino acids were investigated. The chemical structures, including the linkage mode of the N-terminal glutamic acid, of γ-L-glutamyl-S-(2-propenyl)-L-cysteine (γ-L-glutamyl-S-allyl-L-cysteine) and its sulfoxide isolated from garlic were established by comparing their NMR spectra with those of authentic peptides prepared using chemical methods. Mass spectrometric analysis also enabled determination of the linkage modes in the glutamyl dipeptides by their characteristic fragmentation. In sensory evaluation, these peptides exhibited flavor-modifying effects (continuity) in umami solutions less pronounced but similar to that of glutathione. Furthermore, the peptides exhibited intrinsic flavor due to the sulfur-containing structure, which may be partially responsible for their flavor-modifying effects. In CaSR assays, γ-L-glutamyl-S-methyl-L-cysteinylglycine was most active, which indicates that the presence of a medium-sized aliphatic substituent at the second amino acid residue in γ-glutamyl peptides enhances CaSR activity.

Isolation and Identification of Three γ-Glutamyl Tripeptides and Their Putative Production Mechanism in Aged Garlic Extract.

PubMed

Nakamoto, Masashi; Fujii, Takuto; Matsutomo, Toshiaki; Kodera, Yukihiro

2018-03-21

We analyzed aged garlic extract (AGE) to understand its complex sulfur chemistry using post-column high-performance liquid chromatography with an iodoplatinate reagent and liquid chromatography high resolution mass spectrometry (LC-MS). We observed unidentified peaks of putative sulfur compounds. Three compounds were isolated and identified as γ-glutamyl-γ-glutamyl- S-methylcysteine, γ-glutamyl-γ-glutamyl- S-allylcysteine (GGSAC) and γ-glutamyl-γ-glutamyl- S-1-propenyl-cysteine (GGS1PC) by nuclear magnetic resonance and LC-MS analysis based on comparisons with chemically synthesized reference compounds. GGSAC and GGS1PC were novel compounds. Trace amounts of these compounds were detected in raw garlic, but the contents of these compounds increased during the aging process. Production of these compounds was inhibited using a γ-glutamyl transpeptidase (GGT) inhibitor in the model reaction mixtures. These findings suggest that γ-glutamyl tripeptides in AGE are produced by GGT during the aging process.

gamma-Glutamyl transpeptidase overexpression increases metastatic growth of B16 melanoma cells in the mouse liver.

PubMed

Obrador, Elena; Carretero, Julian; Ortega, Angel; Medina, Ignacio; Rodilla, Vicente; Pellicer, José A; Estrela, José M

2002-01-01

B16 melanoma (B16M) cells with high glutathione (GSH) content show rapid proliferation in vitro and high metastatic activity in the liver in vivo. gamma-Glutamyl transpeptidase (GGT)-mediated extracellular GSH cleavage and intracellular GSH synthesis were studied in vitro in B16M cells with high (F10) and low (F1) metastatic potential. GGT activity was modified by transfection with the human GGT gene (B16MF1/Tet-GGT cells) or by acivicin-induced inhibition. B16MF1/Tet-GGT and B16MF10 cells exhibited higher GSH content (35 +/- 6 and 40 +/- 5 nmol/10(6) cells, respectively) and GGT activity (89 +/- 9 and 37 +/- 7 mU/10(6) cells, respectively) as compared (P <.05) with B16MF1 cells (10 +/- 3 nmol GSH and 4 mU GGT/10(6) cells). Metastasis (number of foci/100 mm(3) of liver) increased in B16MF1 cells pretreated with GSH ester ( approximately 3-fold, P <.01), and decreased in B16MF1/Tet-GGT and B16MF10 cells pretreated with the GSH synthesis inhibitor L-buthionine (S,R)-sulphoximine ( approximately 5-fold and 2-fold, respectively, P <.01). Liver, kidney, brain, lung, and erythrocyte GSH content in B16MF1/Tet-GGT- or B16MF10-bearing mice decreased as compared with B16MF1- and non-tumor-bearing mice. Organic anion transporting polypeptide 1-independent sinusoidal GSH efflux from hepatocytes increased in B16MF1/Tet-GGT- or B16MF10-bearing mice ( approximately 2-fold, P <.01) as compared with non-tumor-bearing mice. Our results indicate that tumor GGT activity and an intertissue flow of GSH can regulate GSH content of melanoma cells and their metastatic growth in the liver.

Enzymes of the γ-Glutamyl Cycle in the Ciliary Body and Lens

PubMed Central

Ross, Leonard L.; Barber, Lee; Tate, Suresh S.; Meister, Alton

1973-01-01

The enzymes of the γ-glutamyl cycle have been found in rabbit ciliary body and, except for 5-oxoprolinase, also in the ocular lens. Histochemical studies show that γ-glutamyl transpeptidase is localized mainly in the basal portions of the epithelial cells of the ciliary body; the findings are similar to those observed in the chloroid plexuses. The histochemical staining reaction in the ciliary epithelium is more intense than in the chloroid plexus, intestine, and kidney. γ-Glutamyl transpeptidase staining activity in the epithelium of the intestinal and renal proximal convoluted tubules is confined to the microvillus border. Moderate transpeptidase activity was found in the cytoplasm of nonpigmented epithelial cells of the iris at the posterior pupillary margin. The histochemical and enzyme activity studies are consistent with the thesis that the γ-glutamyl cycle functions in transport of amino acids across the blood-aqueous humor barrier. Images PMID:4152058

Compositions of orthogonal glutamyl-tRNA and aminoacyl-tRNA synthetase pairs and uses thereof

DOEpatents

Anderson, J Christopher [San Francisco, CA; Schultz, Peter G [La Jolla, CA; Santoro, Stephen [Cambridge, MA

2009-05-05

Compositions and methods of producing components of protein biosynthetic machinery that include glutamyl orthogonal tRNAs, glutamyl orthogonal aminoacyl-tRNA synthetases, and orthogonal pairs of glutamyl tRNAs/synthetases are provided. Methods for identifying these orthogonal pairs are also provided along with methods of producing proteins using these orthogonal pairs.

Alcohol, metabolic risk and elevated serum gamma-glutamyl transferase (GGT) in Indigenous Australians.

PubMed

Haren, Matthew T; Li, Ming; Petkov, John; McDermott, Robyn A

2010-08-03

The interaction between overweight/obesity and alcohol intake on liver enzyme concentrations have been demonstrated. No studies have yet examined the interaction between metabolic syndrome or multiple metabolic risk factors and alcohol intake on liver enzymes. The aim of this study was to examine if alcohol consumption modifies the effect of metabolic risk on elevated serum GGT in Indigenous Australians. Data were from N = 2609 Indigenous Australians who participated in a health screening program in rural far north Queensland in 1999-2000 (44.5% response rate). The individual and interactive effects of metabolic risk and alcohol drinking on elevated serum GGT concentrations (>or=50 U/L) were analyzed using logistic regression. Overall, 26% of the population had GGT>or=50 U/L. Elevated GGT was associated with alcohol drinking (moderate drinking: OR 2.3 [95%CI 1.6 - 3.2]; risky drinking: OR 6.0 [4.4 - 8.2]), and with abdominal obesity (OR 3.7 [2.5 - 5.6]), adverse metabolic risk cluster profile (OR 3.4 [2.6 - 4.3]) and metabolic syndrome (OR 2.7 [2.1 - 3.5]) after adjustment for age, sex, ethnicity, smoking, physical activity and BMI. The associations of obesity and metabolic syndrome with elevated GGT were similar across alcohol drinking strata, but the association of an adverse metabolic risk cluster profile with elevated GGT was larger in risky drinkers (OR 4.9 [3.7 - 6.7]) than in moderate drinkers (OR 2.8 [1.6 - 4.9]) and abstainers (OR 1.6 [0.9 - 2.8]). In this Indigenous population, an adverse metabolic profile conferred three times the risk of elevated GGT in risky drinkers compared with abstainers, independent of sex and ethnicity. Community interventions need to target both determinants of the population's metabolic status and alcohol consumption to reduce the risk of elevated GGT.

Alcohol, metabolic risk and elevated serum gamma-glutamyl transferase (GGT) in Indigenous Australians

PubMed Central

2010-01-01

Background The interaction between overweight/obesity and alcohol intake on liver enzyme concentrations have been demonstrated. No studies have yet examined the interaction between metabolic syndrome or multiple metabolic risk factors and alcohol intake on liver enzymes. The aim of this study was to examine if alcohol consumption modifies the effect of metabolic risk on elevated serum GGT in Indigenous Australians. Methods Data were from N = 2609 Indigenous Australians who participated in a health screening program in rural far north Queensland in 1999-2000 (44.5% response rate). The individual and interactive effects of metabolic risk and alcohol drinking on elevated serum GGT concentrations (≥50 U/L) were analyzed using logistic regression. Results Overall, 26% of the population had GGT≥50 U/L. Elevated GGT was associated with alcohol drinking (moderate drinking: OR 2.3 [95%CI 1.6 - 3.2]; risky drinking: OR 6.0 [4.4 - 8.2]), and with abdominal obesity (OR 3.7 [2.5 - 5.6]), adverse metabolic risk cluster profile (OR 3.4 [2.6 - 4.3]) and metabolic syndrome (OR 2.7 [2.1 - 3.5]) after adjustment for age, sex, ethnicity, smoking, physical activity and BMI. The associations of obesity and metabolic syndrome with elevated GGT were similar across alcohol drinking strata, but the association of an adverse metabolic risk cluster profile with elevated GGT was larger in risky drinkers (OR 4.9 [3.7 - 6.7]) than in moderate drinkers (OR 2.8 [1.6 - 4.9]) and abstainers (OR 1.6 [0.9 - 2.8]). Conclusions In this Indigenous population, an adverse metabolic profile conferred three times the risk of elevated GGT in risky drinkers compared with abstainers, independent of sex and ethnicity. Community interventions need to target both determinants of the population's metabolic status and alcohol consumption to reduce the risk of elevated GGT. PMID:20682033

The glutathione cycle: Glutathione metabolism beyond the γ-glutamyl cycle.

PubMed

Bachhawat, Anand Kumar; Yadav, Shambhu

2018-04-17

Glutathione was discovered in 1888, over 125 years ago. Since then, our understanding of various functions and metabolism of this important molecule has grown over these years. But it is only now, in the last decade, that a somewhat complete picture of its metabolism has emerged. Glutathione metabolism has till now been largely depicted and understood by the γ-glutamyl cycle that was proposed in 1970. However, new findings and knowledge particularly on the transport and degradation of glutathione have revealed that many aspects of the γ-glutamyl cycle are incorrect. Despite this, an integrated critical analysis of the cycle has never been undertaken and this has led to the cycle and its errors perpetuating in the literature. This review takes a careful look at the γ-glutamyl cycle and its shortcomings and presents a "glutathione cycle" that captures the current understanding of glutathione metabolism. © 2018 IUBMB Life, 2018. © 2018 International Union of Biochemistry and Molecular Biology.

Escherichia coli gamma-glutamyltranspeptidase mutants deficient in processing to subunits.

PubMed

Hashimoto, W; Suzuki, H; Nohara, S; Kumagai, H

1992-11-30

Arginyl residues 513 and 571 of Escherichia coli K-12 gamma-glutamyl-transpeptidase (EC 2.3.2.2) were substituted with alanyl and glycyl residues, respectively, by oligonucleotide-directed in vitro mutagenesis. Both mutants were devoid of the enzymatic activity. On Western blot analysis, we found that both mutants accumulated a gamma-glutamyltranspeptidase precursor which was not processed into large and small subunits in the periplasmic space of Escherichia coli.

Opposite associations between alanine aminotransferase and γ-glutamyl transferase levels and all-cause mortality in type 2 diabetes: Analysis of the Fenofibrate Intervention and Event Lowering in Diabetes (FIELD) study.

PubMed

Williams, Kathryn H; Sullivan, David R; Nicholson, Geoffrey C; George, Jacob; Jenkins, Alicia J; Januszewski, Andrzej S; Gebski, Val J; Manning, Patrick; Tan, Yong Mong; Donoghoe, Mark W; Ehnholm, Christian; Young, Simon; O'Brien, Richard; Buizen, Luke; Twigg, Stephen M; Keech, Anthony C

2016-05-01

Reported associations between liver enzymes and mortality may not hold true in type 2 diabetes, owing to a high prevalence of non-alcoholic fatty liver disease, which has been linked to cardiovascular disease and mortality in its own right. Our study aimed to determine whether alanine aminotransferase (ALT) or γ-glutamyl transferase (GGT) levels predict mortality in type 2 diabetes, and to examine possible mechanisms. Data from the Fenofibrate Intervention and Event Lowering in Diabetes (FIELD) study were analyzed to examine the relationship between liver enzymes and all-cause and cause-specific mortality over 5years. Over 5years, 679 (6.9%) individuals died. After adjustment, for every standard deviation increase in ALT (13.2U/L), the HR for death on study was 0.85 (95% CI 0.78-0.93), p<0.001. Conversely, GGT >70U/L, compared with GGT ≤70U/L, had HR 1.82 (1.48-2.24), p<0.001. For cause-specific mortality, lower ALT was associated with a higher risk of cardiovascular death only, whereas GGT >70U/L was associated with higher risks of death due to cardiovascular disease, cancer and non-cancer/non-cardiovascular causes. The relationship for ALT persisted after adjustment for indirect measures of frailty but was attenuated by elevated hsCRP. As in the general population, ALT has a negative, and GGT a positive, correlation with mortality in type 2 diabetes when ALT is less than two times the upper limit of normal. The relationship for ALT appears specific for death due to cardiovascular disease. Links of low ALT with frailty, as a potential mechanism for relationships seen, were neither supported nor conclusively refuted by our analysis and other factors are also likely to be important in those with type 2 diabetes. Copyright © 2016 Elsevier Inc. All rights reserved.

Molecular and biochemical characterization of tomato farnesyl-protein transferase.

PubMed

Schmitt, D; Callan, K; Gruissem, W

1996-10-01

The prenylation of membrane-associated proteins involved in the regulation of eukaryotic cell growth and signal transduction is critically important for their subcellular localization and biological activity. In contrast to mammalian cells and yeast, however, the function of protein prenylation in plants is not well understood and only a few prenylated proteins have been identified. We partially purified and characterized farnesyl-protein transferase from tomato (Lycopersicon esculentum, LeFTase) to analyze its biochemical and molecular properties. Using Ras- and G gamma-specific peptide substrates and competition assays we showed that tomato protein extracts have both farnesyl-protein transferase and geranylgeranyl-protein transferase 1 activities. Compared with the heterologous synthetic peptide substrates, the plant-specific CaaX sequence of the ANJ1 protein is a less efficient substrate for LeFTase in vitro. LeFTase activity profiles and LeFTase beta-subunit protein (LeFTB) levels differ significantly in various tissues and are regulated during fruit development. Partially purified LeFTase requires Zn2+ and Mg2+ for enzymatic activity and has an apparent molecular mass of 100 kD Immunoprecipitation experiments using anti-alpha LeFTB antibodies confirmed that LeFTB is a component of LeFTase but not of tomato geranylgeranyl-protein transferase 1. Based on their conserved bio-chemical activities, we expect that prenyltransferases are likely integrated with the sterol biosynthesis pathway in the control of plant cell growth.

Structural snapshots along the reaction pathway of Yersinia pestis RipA, a putative butyryl-CoA transferase

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

Torres, Rodrigo; Lan, Benson; Latif, Yama

2014-04-01

The crystal structures of Y. pestis RipA mutants were determined to provide insights into the CoA transferase reaction pathway. Yersinia pestis, the causative agent of bubonic plague, is able to survive in both extracellular and intracellular environments within the human host, although its intracellular survival within macrophages is poorly understood. A novel Y. pestis three-gene rip (required for intracellular proliferation) operon, and in particular ripA, has been shown to be essential for survival and replication in interferon γ-induced macrophages. RipA was previously characterized as a putative butyryl-CoA transferase proposed to yield butyrate, a known anti-inflammatory shown to lower macrophage-produced NOmore » levels. RipA belongs to the family I CoA transferases, which share structural homology, a conserved catalytic glutamate which forms a covalent CoA-thioester intermediate and a flexible loop adjacent to the active site known as the G(V/I)G loop. Here, functional and structural analyses of several RipA mutants are presented in an effort to dissect the CoA transferase mechanism of RipA. In particular, E61V, M31G and F60M RipA mutants show increased butyryl-CoA transferase activities when compared with wild-type RipA. Furthermore, the X-ray crystal structures of E61V, M31G and F60M RipA mutants, when compared with the wild-type RipA structure, reveal important conformational changes orchestrated by a conserved acyl-group binding-pocket phenylalanine, Phe85, and the G(V/I)G loop. Binary structures of M31G RipA and F60M RipA with two distinct CoA substrate conformations are also presented. Taken together, these data provide CoA transferase reaction snapshots of an open apo RipA, a closed glutamyl-anhydride intermediate and an open CoA-thioester intermediate. Furthermore, biochemical analyses support essential roles for both the catalytic glutamate and the flexible G(V/I)G loop along the reaction pathway, although further research is required to fully

Moderate doses of commercial preparations of Ginkgo biloba do not alter markers of liver function but moderate alcohol intake does: A new approach to identify and quantify biomarkers of 'adverse effects' of dietary supplements.

PubMed

Lieberman, Harris R; Kellogg, Mark D; Fulgoni, Victor L; Agarwal, Sanjiv

2017-03-01

It is difficult to determine if certain dietary supplements are safe for human consumption. Extracts of leaves of Ginkgo biloba trees are dietary supplements used for various purported therapeutic benefits. However, recent studies reported they increased risk of liver cancer in rodents. Therefore, this study assessed the association between ginkgo consumption and liver function using NHANES 2001-2012 data (N = 29,684). Since alcohol is known to adversely affect liver function, association of its consumption with liver function was also assessed. Alcohol and ginkgo extract intake of adult consumers and clinical markers of liver function (alkaline phosphatase, alanine aminotransferase, aspartate aminotransferase, gamma glutamyl transferase, lactate dehydrogenase, bilirubin) were examined. Moderate consumers of alcohol (0.80 ± 0.02 drinks/day) had higher levels of aspartate aminotransferase and gamma glutamyl transferase than non-consumers (P < 0.001). There was no difference (P > 0.01) in levels of markers of liver function in 616 ginkgo consumers (65.1 ± 4.4 mg/day intake) compared to non-consumers. While moderate alcohol consumption was associated with changes in markers of liver function, ginkgo intake as typically consumed by U.S. adults was not associated with these markers. Biomarkers measured by NHANES may be useful to examine potential adverse effects of dietary supplements for which insufficient human adverse event and toxicity data are available. Not applicable, as this is secondary analysis of publicly released observational data (NHANES 2001-2012). Published by Elsevier Inc.

Post-translational glutamylation and tyrosination in tubulin of tritrichomonads and the diplomonad Giardia intestinalis.

PubMed

Boggild, A K; Sundermann, C A; Estridge, B H

2002-01-01

Glutamylated and tyrosinated tubulin were localized in Giardia intestinalis and selected trichomonads of the Tritrichomonadinae subfamily, using specific monoclonal antibodies directed at each of the post-translational modifications. Analysis was carried out using indirect immunofluorescence microscopy. Although trichomonad tubulins remained unlabeled by anti-tyrosine tubulin (TUB-1A2), the presence of the glutamylation motif (GT 335) was confirmed and found to differ in distribution among tritrichomonads. Tritrichomonas muris was most heavily labeled with GT 335, while T. foetus was the least so. Like trichomonads, Giardia was unreactive to anti-tyrosine tubulin; however, the GT 335 antibody produced marked fluorescence in Giardia trophozoites. This study is the first to report immunofluorescent localization of tubulin glutamylation in Giardia and confirms previously reported mass spectrometry data.

Gamma-glutamyl-transpeptidase to platelet ratio is not superior to APRI,FIB-4 and RPR for diagnosing liver fibrosis in CHB patients in China.

PubMed

Huang, Rui; Wang, Guiyang; Tian, Chen; Liu, Yong; Jia, Bei; Wang, Jian; Yang, Yue; Li, Yang; Sun, Zhenhua; Yan, Xiaomin; Xia, Juan; Xiong, Yali; Song, Peixin; Zhang, Zhaoping; Ding, Weimao; Wu, Chao

2017-08-17

The gamma-glutamyl transpeptidase to platelet ratio (GPR) is a novel index to estimate liver fibrosis in chronic hepatitis B (CHB). Few studies compared diagnostic accuracy of GPR with other non-invasive fibrosis tests based on blood parameters. We analyzed diagnostic values of GPR for detecting liver fibrosis and compared diagnostic performances of GPR with APRI (aspartate aminotransferase-to-platelet ratio index), FIB-4 (fibrosis index based on the four factors), NLR (neutrophil-to-lymphocyte ratio), AAR (aspartate aminotransferase/alanine aminotransferase ratio) and RPR (red cell distribution width-to-platelet ratio) in HBeAg positive CHB and HBeAg negative CHB. We found AUROCs of GPR in predicting significant liver fibrosis, advanced liver fibrosis and liver cirrhosis were 0.732 (95% CI 0.663 to 0.801), 0.788 (95% CI 0.729 to 0.847) and 0.753 (95% CI 0.692 to 0.814), respectively. Further comparisons showed the diagnostic performance of GPR was not significantly different with APRI, FIB-4 and RPR in identifying significant fibrosis, advanced fibrosis and cirrhosis, but it was significantly superior to AAR and NLR in both HBeAg positive CHB and HBeAg negative CHB. In conclusion, GPR does not show advantages than APRI, FIB-4 and RPR in identifying significant liver fibrosis, advanced liver fibrosis and liver cirrhosis in both HBeAg positive CHB and HBeAg negative CHB in China.

Structure of 6-diazo-5-oxo-norleucine-bound human gamma-glutamyl transpeptidase 1, a novel mechanism of inactivation

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

Terzyan, Simon S.; Cook, Paul F.; Heroux, Annie

Intense efforts are underway to identify inhibitors of the enzyme gamma–glutamyl transpeptidase 1 (GGT1) which cleaves extracellular gamma–glutamyl compounds and contributes to the pathology of asthma, reperfusion injury and cancer. The glutamate analog, 6–diazo–5–oxo–norleucine (DON), inhibits GGT1. DON also inhibits many essential glutamine metabolizing enzymes rendering it too toxic for use in the clinic as a GGT1 inhibitor. We investigated the molecular mechanism of human GGT1 (hGGT1) inhibition by DON to determine possible strategies for increasing its specificity for hGGT1. DON is an irreversible inhibitor of hGGT1. The second order rate constant of inactivation was 0.052 m M –1 minmore » –1 and the K i was 2.7 ± 0.7 m M. The crystal structure of DON–inactivated hGGT1 contained a molecule of DON without the diazo–nitrogen atoms in the active site. The overall structure of the hGGT1–DON complex resembled the structure of the apo–enzyme; however, shifts were detected in the loop forming the oxyanion hole and elements of the main chain that form the entrance to the active site. The structure of hGGT1–DON complex revealed two covalent bonds between the enzyme and inhibitor which were part of a six membered ring. The ring included the OG atom of Thr381, the reactive nucleophile of hGGT1 and the α–amine of Thr381. As a result, the structure of DON–bound hGGT1 has led to the discovery of a new mechanism of inactivation by DON that differs from its inactivation of other glutamine metabolizing enzymes, and insight into the activation of the catalytic nucleophile that initiates the hGGT1 reaction.« less

Structure of 6-diazo-5-oxo-norleucine-bound human gamma-glutamyl transpeptidase 1, a novel mechanism of inactivation

DOE PAGES

Terzyan, Simon S.; Cook, Paul F.; Heroux, Annie; ...

2017-04-05

Intense efforts are underway to identify inhibitors of the enzyme gamma–glutamyl transpeptidase 1 (GGT1) which cleaves extracellular gamma–glutamyl compounds and contributes to the pathology of asthma, reperfusion injury and cancer. The glutamate analog, 6–diazo–5–oxo–norleucine (DON), inhibits GGT1. DON also inhibits many essential glutamine metabolizing enzymes rendering it too toxic for use in the clinic as a GGT1 inhibitor. We investigated the molecular mechanism of human GGT1 (hGGT1) inhibition by DON to determine possible strategies for increasing its specificity for hGGT1. DON is an irreversible inhibitor of hGGT1. The second order rate constant of inactivation was 0.052 m M –1 minmore » –1 and the K i was 2.7 ± 0.7 m M. The crystal structure of DON–inactivated hGGT1 contained a molecule of DON without the diazo–nitrogen atoms in the active site. The overall structure of the hGGT1–DON complex resembled the structure of the apo–enzyme; however, shifts were detected in the loop forming the oxyanion hole and elements of the main chain that form the entrance to the active site. The structure of hGGT1–DON complex revealed two covalent bonds between the enzyme and inhibitor which were part of a six membered ring. The ring included the OG atom of Thr381, the reactive nucleophile of hGGT1 and the α–amine of Thr381. As a result, the structure of DON–bound hGGT1 has led to the discovery of a new mechanism of inactivation by DON that differs from its inactivation of other glutamine metabolizing enzymes, and insight into the activation of the catalytic nucleophile that initiates the hGGT1 reaction.« less

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

PubMed

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

2009-05-01

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

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

PubMed Central

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

2018-01-01

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

Tubulin Glutamylation Regulates Ciliary Motility by Altering Inner Dynein Arm Activity

PubMed Central

Suryavanshi, Swati; Eddé, Bernard; Fox, Laura A.; Guerrero, Stella; Hard, Robert; Hennessey, Todd; Kabi, Amrita; Malison, David; Pennock, David; Sale, Winfield S.; Wloga, Dorota; Gaertig, Jacek

2010-01-01

SUMMMARY How microtubule-associated motor proteins are regulated is not well understood. A potential mechanism for spatial regulation of motor proteins is provided by post-translational modifications of tubulin subunits that form patterns on microtubules. Glutamylation is a conserved tubulin modification [1] that is enriched in axonemes. The enzymes responsible for this PTM, glutamic acid ligases (E-ligases), belong to a family of proteins with a tubulin tyrosine ligase (TTL) homology domain (TTL-like or TTLL proteins) [2]. We show that in cilia of Tetrahymena, TTLL6 E-ligases generate glutamylation mainly on the B-tubule of outer doublet microtubules, the site of force production by ciliary dynein. Deletion of two TTLL6 paralogs caused severe deficiency in ciliary motility associated with abnormal waveform and reduced beat frequency. In isolated axonemes with a normal dynein arm composition, TTLL6 deficiency did not affect the rate of ATP-induced doublet microtubule sliding. Unexpectedly, the same TTLL6 deficiency increased the velocity of microtubule sliding in axonemes that also lack outer dynein arms, in which forces are generated by inner dynein arms. We conclude that tubulin glutamylation on the B-tubule inhibits the net force imposed on sliding doublet microtubules by inner dynein arms. PMID:20189389

Associations between arterial structure and function and serum levels of liver enzymes in obese adolescents.

PubMed

Man, Elim; Cheung, Pik-To; Cheung, Yiu-Fai

2017-07-01

To determine the structural and functional alterations of systemic arteries in obese adolescents and their relationships with adiposity, metabolic and lipid profile, and serum liver enzyme levels. Carotid intima-media thickness (IMT), carotid stiffness index, and brachial-ankle pulse wave velocity (baPWV) were measured in 56 obese adolescents and 58 lean controls. Obese adolescents had additional liver ultrasound and determination of fasting blood indices of glucose metabolism and lipid profile, and serum levels of liver enzymes. Carotid IMT (P < 0.0001), carotid stiffness index (P < 0.0001) and baPWV (P = 0.001) were significantly greater in obese than control subjects. Thirty-seven (66%) obese subjects had fatty liver changes and their aspartate aminotransferase, alanine aminotransferase (ALT), alkaline phosphatase, and gamma-glutamyl transferase levels were significantly higher than those without (all P < 0.05). Univariate analyses showed positive correlations between serum ALT (r = 0.29, P = 0.03) and alkaline phosphatase (r = 0.28, P = 0.04) levels and carotid IMT, aspartate aminotransferase level and carotid stiffness (r = 0.41, P = 0.002), and gamma-glutamyl transferase level and baPWV (r = 0.34, P = 0.02) in obese subjects. Multivariate linear regression revealed serum ALT level (β = 0.02, P = 0.006) as an independent correlate of carotid stiffness. Obese adolescents have increased carotid IMT and stiffness, which are associated positively with serum liver enzyme levels. © 2017 Paediatrics and Child Health Division (The Royal Australasian College of Physicians).

Comparative assessment of a DNA and protein Leishmania donovani gamma glutamyl cysteine synthetase vaccine to cross-protect against murine cutaneous leishmaniasis caused by L. major or L. mexicana infection.

PubMed

Campbell, S A; Alawa, J; Doro, B; Henriquez, F L; Roberts, C W; Nok, A; Alawa, C B I; Alsaadi, M; Mullen, A B; Carter, K C

2012-02-08

Leishmaniasis is a major health problem and it is estimated that 12 million people are currently infected. A vaccine which could cross-protect people against different Leishmania spp. would facilitate control of this disease as more than one species of Leishmania may be present. In this study the ability of a DNA vaccine, using the full gene sequence for L. donovani gamma glutamyl cysteine synthetase (γGCS) incorporated in the pVAX vector (pVAXγGCS), and a protein vaccine, using the corresponding recombinant L. donovani γGCS protein (LdγGCS), to protect against L. major or L. mexicana infection was evaluated. DNA vaccination gave transient protection against L. major and no protection against L. mexicana despite significantly enhancing specific antibody titres in vaccinated infected mice compared to infected controls. Vaccination with the LdγGCS protected against both species but only if the protein was incorporated into non-ionic surfactant vesicles for L. mexicana. The results of this study indicate that a L. donovani γGCS vaccine could be used to vaccinate against more than one Leishmania species but only if the recombinant protein is used. Copyright © 2012 Elsevier Ltd. All rights reserved.

The Effects of Exercise on Abdominal Fat and Liver Enzymes in Pediatric Obesity: A Systematic Review and Meta-Analysis.

PubMed

González-Ruiz, Katherine; Ramírez-Vélez, Robinson; Correa-Bautista, Jorge Enrique; Peterson, Mark D; García-Hermoso, Antonio

2017-08-01

Despite the prevalence of obesity and the multiple position stands promoting exercise for the treatment of obesity and hepatic function, a meta-analytic approach has not previously been used to examine the effects in the pediatric population. The aim of the study was to determine the effectiveness of exercise interventions on abdominal fat, liver enzymes, and intrahepatic fat in overweight and obese youth. A computerized search was made using three databases. The analysis was restricted to studies that examined the effect of supervised exercise interventions on abdominal fat (visceral and subcutaneous fat), liver enzymes (alanine aminotransferase, aspartate aminotransferase, and gamma-glutamyl transferase), and intrahepatic fat. Fourteen clinical trials (1231 youths) were eligible for inclusion in this systematic review and meta-analysis. Standardized mean difference [SMD] and 95% confidence intervals (CIs) were calculated. Exercise was associated with a significant reduction in visceral (SMD = -0.661; 95% CI, -0.976 to -0.346; p < 0.001), subcutaneous (SMD = -0.352; 95% CI, -0.517 to -0.186; p < 0.001) and intrahepatic fat (SMD = -0.802; 95% CI, -1.124 to -0.480; p < 0.001), as well as gamma-glutamyl transferase (SMD = -0.726; 95% CI, -1.203 to -0.249; p < 0.001), but did not alter any other liver enzyme. Subgroup analysis recommends exercise programs that involve aerobic exercise longer than three sessions per week. This meta-analysis supports current recommendation for physical exercise, mainly aerobic, as an effective intervention for nonalcoholic fatty liver disease progression by targeting hepatic lipid composition, visceral and subcutaneous adipose tissue. Systematic review registration: PROSPERO CRD42016042163.

Evaluation of clinical and paraclinical effects of intraosseous vs intravenous administration of propofol on general anesthesia in rabbits

PubMed Central

Mazaheri-Khameneh, Ramin; Sarrafzadeh-Rezaei, Farshid; Asri-Rezaei, Siamak; Dalir-Naghadeh, Bahram

2012-01-01

This prospective study aimed to compare the intraosseous (IO) and intravenous (IV) effects of propofol on selected blood parameters and physiological variables during general anesthesia in rabbits. Thirty New Zealand White rabbits were studied. Six rabbits received IV propofol (group 1) and another 6 rabbits, were injected propofol intraosseously (Group 2) for 30 minutes (experimental groups). Rabbits of the third and fourth groups received IV and IO normal saline at the same volume given to the experimental groups, respectively. In the fifth group IO cannulation was performed but neither propofol nor normal saline were administered. Blood profiles were assayed before induction and after recovery of anesthesia. Heart and respiratory rates, rectal temperature, saturation of peripheral oxygen and mean arterial blood pressure were recorded. Heart rate increased significantly 1 to 5 minutes after induction of anesthesia in experimental groups (P < 0.05). Although mean arterial blood pressure decreased significantly from baseline, values remained above 60 mm Hg (P < 0.05). Respiratory rate decreased significantly in experimental groups, but remained higher in group 2 (P < 0.05). The lymphocyte count decreased significantly in group 1 (P < 0.05). The concentration of alkaline phosphatase in all rabbits, aspartate aminotransferase and gamma-glutamyl transferase in the first group and gamma-glutamyl transferase in the third group increased significantly (P < 0.05). Total bilirubin decreased significantly in group 2 (P < 0.05). All measured values remained within normal limits. Based on the least significant physiological, hematological and biochemical effects, the IO injection of propofol appears to be safe and suitable method of anesthesia in rabbits with limited vascular access. PMID:25653755

Evaluation of clinical and paraclinical effects of intraosseous vs intravenous administration of propofol on general anesthesia in rabbits.

PubMed

Mazaheri-Khameneh, Ramin; Sarrafzadeh-Rezaei, Farshid; Asri-Rezaei, Siamak; Dalir-Naghadeh, Bahram

2012-01-01

This prospective study aimed to compare the intraosseous (IO) and intravenous (IV) effects of propofol on selected blood parameters and physiological variables during general anesthesia in rabbits. Thirty New Zealand White rabbits were studied. Six rabbits received IV propofol (group 1) and another 6 rabbits, were injected propofol intraosseously (Group 2) for 30 minutes (experimental groups). Rabbits of the third and fourth groups received IV and IO normal saline at the same volume given to the experimental groups, respectively. In the fifth group IO cannulation was performed but neither propofol nor normal saline were administered. Blood profiles were assayed before induction and after recovery of anesthesia. Heart and respiratory rates, rectal temperature, saturation of peripheral oxygen and mean arterial blood pressure were recorded. Heart rate increased significantly 1 to 5 minutes after induction of anesthesia in experimental groups (P < 0.05). Although mean arterial blood pressure decreased significantly from baseline, values remained above 60 mm Hg (P < 0.05). Respiratory rate decreased significantly in experimental groups, but remained higher in group 2 (P < 0.05). The lymphocyte count decreased significantly in group 1 (P < 0.05). The concentration of alkaline phosphatase in all rabbits, aspartate aminotransferase and gamma-glutamyl transferase in the first group and gamma-glutamyl transferase in the third group increased significantly (P < 0.05). Total bilirubin decreased significantly in group 2 (P < 0.05). All measured values remained within normal limits. Based on the least significant physiological, hematological and biochemical effects, the IO injection of propofol appears to be safe and suitable method of anesthesia in rabbits with limited vascular access.

Upregulation of High Mobility Group Box 1 May Contribute to the Pathogenesis of Biliary Atresia.

PubMed

Ye, Chun Jing; Wang, Jiang; Yang, Yi Fan; Shen, Zhen; Chen, Gong; Huang, Yan Lei; Zheng, Yi Jie; Dong, Rui; Zheng, Shan

2018-06-17

 Biliary atresia (BA) is a progressive inflammatory obstructive cholangiopathy in infants. High mobility group box 1 (HMGB1) is known to play an important role as a late mediator of inflammation. However, it is not clear whether HMGB1 levels are of clinical significance in patients with BA. The aim of this study was to determine correlations between serum HMGB1 levels and the clinicopathologic features of BA.  Serum samples were collected from 19 infants with BA, 7 infants with anicteric choledochal cysts (CC) and normal liver function, and 8 healthy controls. Serum HMGB1 levels were measured with an enzyme-linked immunosorbent assay. Routine liver function tests were performed on serum samples. Quantitative real-time polymerase chain reaction and western blot analyses were used to detect HMGB1 expression in BA liver biopsy tissues. Localization of HMGB1 expression in the hepatic lobule was determined by immunohistochemical analysis.  HMGB1 levels in serum collected from BA infants were significantly elevated compared with CC and healthy control patients. Furthermore, elevated serum levels of HMGB1 in BA infants positively correlated with gamma-glutamyl transferase levels. HMGB1 messenger ribonucleic acid and protein expression levels were upregulated in BA liver biopsy tissues compared with CC patients. Immunohistochemical analysis also revealed increased positive immunostaining for HMGB1 in BA liver tissues as compared with CC tissues.  HMGB1 may play a crucial role in the pathogenesis of BA. Additionally, the correlation of serum HMGB1 levels with gamma-glutamyl transferase levels may provide a novel marker for the diagnosis of BA. Georg Thieme Verlag KG Stuttgart · New York.

Hibiscus cannabinus feruloyl-coa:monolignol transferase

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

Wilkerson, Curtis; Ralph, John; Withers, Saunia

The invention relates to isolated nucleic acids encoding a feruloyl-CoA:monolignol transferase and feruloyl-CoA:monolignol transferase enzymes. The isolated nucleic acids and/or the enzymes enable incorporation of monolignol ferulates into the lignin of plants, where such monolignol ferulates include, for example, p-coumaryl ferulate, coniferyl ferulate, and/or sinapyl ferulate. The invention also includes methods and plants that include nucleic acids encoding a feruloyl-CoA:monolignol transferase enzyme and/or feruloyl-CoA:monolignol transferase enzymes.

Enzymatic Glycosylation by Transferases

NASA Astrophysics Data System (ADS)

Blixt, Ola; Razi, Nahid

Glycosyltransferases are important biological catalysts in cellular systems generating complex cell surface glycans involved in adhesion and signaling processes. Recent advances in glycoscience have increased the demands to access significant amount of glycans representing the glycome. Glycosyltransferases are now playing a key role for in vitro synthesis of oligosaccharides and the bacterial genome are increasingly utilized for cloning and over expression of active transferases in glycosylation reactions. This chapter highlights the recent progress towards preparative synthesis of oligosaccharides representing terminal sequences of glycoproteins and glycolipids using recombinant transferases. Transferases are also being explored in the context of solid-phase synthesis, immobilized on resins and over expression in vivo by engineered bacteria.

The γ-Glutamyl Cycle in the Choroid Plexus: Its Possible Function in Amino Acid Transport

PubMed Central

Tate, Suresh S.; Ross, Leonard L.; Meister, Alton

1973-01-01

Various anatomic regions of rabbit brain have been examined for activities of the enzymes of the γ-glutamyl cycle. While these enzyme activities were widely distributed in the brain, they are present in much higher concentrations in the choroid plexus than in other parts of the brain. The activities observed are of about the same order of magnitude as found in the kidney. These observations and other considerations suggest that the γ-glutamyl cycle may play a significant role in the transport of amino acids between blood and cerebrospinal fluid. PMID:4145786

A γ-glutamyl cyclotransferase protects Arabidopsis plants from heavy metal toxicity by recycling glutamate to maintain glutathione homeostasis.

PubMed

Paulose, Bibin; Chhikara, Sudesh; Coomey, Joshua; Jung, Ha-Il; Vatamaniuk, Olena; Dhankher, Om Parkash

2013-11-01

Plants detoxify toxic metals through a GSH-dependent pathway. GSH homeostasis is maintained by the γ-glutamyl cycle, which involves GSH synthesis and degradation and the recycling of component amino acids. The enzyme γ-glutamyl cyclotransferase (GGCT) is involved in Glu recycling, but the gene(s) encoding GGCT has not been identified in plants. Here, we report that an Arabidopsis thaliana protein with a cation transport regulator-like domain, hereafter referred to as GGCT2;1, functions as γ-glutamyl cyclotransferase. Heterologous expression of GGCT2;1 in Saccharomyces cerevisiae produced phenotypes that were consistent with decreased GSH content attributable to either GSH degradation or the diversion of γ-glutamyl peptides to produce 5-oxoproline (5-OP). 5-OP levels were further increased by the addition of arsenite and GSH to the medium, indicating that GGCT2;1 participates in the cellular response to arsenic (As) via GSH degradation. Recombinant GGCT2;1 converted both GSH and γ-glutamyl Ala to 5-OP in vitro. GGCT2;1 transcripts were upregulated in As-treated Arabidopsis, and ggct2;1 knockout mutants were more tolerant to As and cadmium than the wild type. Overexpression of GGCT2;1 in Arabidopsis resulted in the accumulation of 5-OP. Under As toxicity, the overexpression lines showed minimal changes in de novo Glu synthesis, while the ggct2;1 mutant increased nitrogen assimilation by severalfold, resulting in a very low As/N ratio in tissue. Thus, our results suggest that GGCT2;1 ensures sufficient GSH turnover during abiotic stress by recycling Glu.

Feruloyl-CoA:monolignol transferase

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

Wilkerson, Curtis; Ralph, John; Withers, Saunia

The invention relates to nucleic acids encoding a feruloyl-CoA:monolignol transferase and the feruloyl-CoA:monolignol transferase enzyme that enables incorporation of monolignol ferulates, for example, including p-coumaryl ferulate, coniferyl ferulate, and sinapyl ferulate, into the lignin of plants.

tRNAGlu increases the affinity of glutamyl-tRNA synthetase for its inhibitor glutamyl-sulfamoyl-adenosine, an analogue of the aminoacylation reaction intermediate glutamyl-AMP: mechanistic and evolutionary implications.

PubMed

Blais, Sébastien P; Kornblatt, Jack A; Barbeau, Xavier; Bonnaure, Guillaume; Lagüe, Patrick; Chênevert, Robert; Lapointe, Jacques

2015-01-01

For tRNA-dependent protein biosynthesis, amino acids are first activated by aminoacyl-tRNA synthetases (aaRSs) yielding the reaction intermediates aminoacyl-AMP (aa-AMP). Stable analogues of aa-AMP, such as aminoacyl-sulfamoyl-adenosines, inhibit their cognate aaRSs. Glutamyl-sulfamoyl-adenosine (Glu-AMS) is the best known inhibitor of Escherichia coli glutamyl-tRNA synthetase (GluRS). Thermodynamic parameters of the interactions between Glu-AMS and E. coli GluRS were measured in the presence and in the absence of tRNA by isothermal titration microcalorimetry. A significant entropic contribution for the interactions between Glu-AMS and GluRS in the absence of tRNA or in the presence of the cognate tRNAGlu or of the non-cognate tRNAPhe is indicated by the negative values of -TΔSb, and by the negative value of ΔCp. On the other hand, the large negative enthalpy is the dominant contribution to ΔGb in the absence of tRNA. The affinity of GluRS for Glu-AMS is not altered in the presence of the non-cognate tRNAPhe, but the dissociation constant Kd is decreased 50-fold in the presence of tRNAGlu; this result is consistent with molecular dynamics results indicating the presence of an H-bond between Glu-AMS and the 3'-OH oxygen of the 3'-terminal ribose of tRNAGlu in the Glu-AMS•GluRS•tRNAGlu complex. Glu-AMS being a very close structural analogue of Glu-AMP, its weak binding to free GluRS suggests that the unstable Glu-AMP reaction intermediate binds weakly to GluRS; these results could explain why all the known GluRSs evolved to activate glutamate only in the presence of tRNAGlu, the coupling of glutamate activation to its transfer to tRNA preventing unproductive cleavage of ATP.

tRNAGlu Increases the Affinity of Glutamyl-tRNA Synthetase for Its Inhibitor Glutamyl-Sulfamoyl-Adenosine, an Analogue of the Aminoacylation Reaction Intermediate Glutamyl-AMP: Mechanistic and Evolutionary Implications

PubMed Central

Blais, Sébastien P.; Kornblatt, Jack A.; Barbeau, Xavier; Bonnaure, Guillaume; Lagüe, Patrick; Chênevert, Robert; Lapointe, Jacques

2015-01-01

For tRNA-dependent protein biosynthesis, amino acids are first activated by aminoacyl-tRNA synthetases (aaRSs) yielding the reaction intermediates aminoacyl-AMP (aa-AMP). Stable analogues of aa-AMP, such as aminoacyl-sulfamoyl-adenosines, inhibit their cognate aaRSs. Glutamyl-sulfamoyl-adenosine (Glu-AMS) is the best known inhibitor of Escherichia coli glutamyl-tRNA synthetase (GluRS). Thermodynamic parameters of the interactions between Glu-AMS and E. coli GluRS were measured in the presence and in the absence of tRNA by isothermal titration microcalorimetry. A significant entropic contribution for the interactions between Glu-AMS and GluRS in the absence of tRNA or in the presence of the cognate tRNAGlu or of the non-cognate tRNAPhe is indicated by the negative values of –TΔSb, and by the negative value of ΔCp. On the other hand, the large negative enthalpy is the dominant contribution to ΔGb in the absence of tRNA. The affinity of GluRS for Glu-AMS is not altered in the presence of the non-cognate tRNAPhe, but the dissociation constant K d is decreased 50-fold in the presence of tRNAGlu; this result is consistent with molecular dynamics results indicating the presence of an H-bond between Glu-AMS and the 3’-OH oxygen of the 3’-terminal ribose of tRNAGlu in the Glu-AMS•GluRS•tRNAGlu complex. Glu-AMS being a very close structural analogue of Glu-AMP, its weak binding to free GluRS suggests that the unstable Glu-AMP reaction intermediate binds weakly to GluRS; these results could explain why all the known GluRSs evolved to activate glutamate only in the presence of tRNAGlu, the coupling of glutamate activation to its transfer to tRNA preventing unproductive cleavage of ATP. PMID:25860020

Serum chemistry concentrations of captive woolly monkeys (Lagothrix lagotricha).

PubMed

Ange-van Heugten, Kimberly; Verstegen, Martin; Ferket, Peter R; Stoskopf, Michael; van Heugten, Eric

2008-05-01

Woolly monkeys (Lagothrix sp.) are threatened species and numerous zoos have failed to sustain successful populations. The most common causes of death in captive woolly monkeys are related to pregnancy and hypertension. The objective of this retrospective study was to evaluate serum concentrations of a large number of captive woolly monkeys to establish baseline means and compare these concentrations with their closest related species to determine potential abnormalities. Serum analyses from 30 woolly monkeys housed at two institutions (Apenheul, The Netherlands and The Louisville Zoo, KY, USA) over 12 yr were collected. The statistical model included gender, age group (young, 0-4 yr of age; middle, 5-9 yr; and old, 10+ yr), and zoological institution. All panel result means were similar to previously reported concentrations for howler (Alouatta sp.) and spider monkeys (Ateles sp.) with the possible exception of alanine aminotransferase and gamma-glutamyl-transferase being higher, whereas creatinine and phosphorus were lower. The serum glucose mean of 6.7 mmol/L is above the baseline range for humans and spider monkeys. Alkaline phosphatase (ALP), alanine aminotransferase, and sodium (Na) were higher in females and magnesium (Mg) was higher in males (P<0.05). ALP, Mg, and phosphorus were highest (P<0.05) and calcium and sodium tended to be highest (P<0.10) in the oldest animals. Ferritin tended to be highest (P<0.10) in the oldest animals. Albumin, ALP, chloride, Na, and total bilirubin were higher for Zoo A, whereas gamma-glutamyl-transferase, glucose, and lactate dehydrogenase were lower for Zoo A (P<0.05). Areas of potential woolly monkey health risk were noted and discussed. Future studies are needed to determine free-ranging serum concentrations to elucidate parameters that contain aberrant concentrations and decrease health status. Zoo Biol 27:188-199, 2008. (c) 2008 Wiley-Liss, Inc.

Efficacy and safety of fermented garlic extract on hepatic function in adults with elevated serum gamma-glutamyl transpeptidase levels: a double-blind, randomized, placebo-controlled trial.

PubMed

Kim, Ha-Na; Kang, Sung-Goo; Roh, Yong Kyun; Choi, Min-Kyu; Song, Sang-Wook

2017-08-01

Alcoholic liver disease or non-alcoholic fatty liver disease/non-alcoholic steatohepatitis are well-known risk factors for liver fibrosis or cirrhosis and hepatocellular carcinoma; it is a major global health concern, but there are few effective and safe management options. Therefore, we aimed to investigate the effects of fermented garlic extracts (FGEs) on hepatic function in adults with mild hepatic dysfunction without underlying hepatic disease. In this double-blind, randomized, placebo-controlled study, seventy-five adults with elevated serum gamma-glutamyl transpeptidase (GGT) levels were included in a FGE-administered group (n = 36) or a placebo group (n = 39), and received either two sachets/day containing FGEs or placebo over a 12-week period. Primary endpoint was the change in serum GGT levels. Data were analysed using a generalized linear mixed effects model. Significant group × time interactions for serum levels of GGT (F = 3.98, P = 0.022) and alanine aminotransferase (ALT; F = 3.28, P = 0.043) were observed with an improvement in levels of GGT (P = 0.066) and ALT (P = 0.014) in the FGE group compared to that reported for the placebo group at the 12-week visits. There was no intergroup difference in the prevalence of adverse events. Intake of FGEs improved serum GGT and ALT levels in adults with mildly elevated serum GGT level without reported adverse side effects. FGEs might be effective and safe management options for mild hepatic dysfunction.

A γ-Glutamyl Transpeptidase-Independent Pathway of Glutathione Catabolism to Glutamate via 5-Oxoproline in Arabidopsis1[W][OA

PubMed Central

Ohkama-Ohtsu, Naoko; Oikawa, Akira; Zhao, Ping; Xiang, Chengbin; Saito, Kazuki; Oliver, David J.

2008-01-01

The degradation pathway of glutathione (GSH) in plants is not well understood. In mammals, GSH is predominantly metabolized through the γ-glutamyl cycle, where GSH is degraded by the sequential reaction of γ-glutamyl transpeptidase (GGT), γ-glutamyl cyclotransferase, and 5-oxoprolinase to yield glutamate (Glu) and dipeptides that are subject to peptidase action. In this study, we examined if GSH is degraded through the same pathway in Arabidopsis (Arabidopsis thaliana) as occurs in mammals. In Arabidopsis, the oxoprolinase knockout mutants (oxp1-1 and oxp1-2) accumulate more 5-oxoproline (5OP) and less Glu than wild-type plants, suggesting substantial metabolite flux though 5OP and that 5OP is a major contributor to Glu steady-state levels. In the ggt1-1/ggt4-1/oxp1-1 triple mutant with no GGT activity in any organs except young siliques, the 5OP concentration in leaves was not different from that in oxp1-1, suggesting that GGTs are not major contributors to 5OP production in Arabidopsis. 5OP formation strongly tracked the level of GSH in Arabidopsis plants, suggesting that GSH is the precursor of 5OP in a GGT-independent reaction. Kinetics analysis suggests that γ-glutamyl cyclotransferase is the major source of GSH degradation and 5OP formation in Arabidopsis. This discovery led us to propose a new pathway for GSH turnover in plants where GSH is converted to 5OP and then to Glu by the combined action of γ-glutamyl cyclotransferase and 5-oxoprolinase in the cytoplasm. PMID:18768907

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

PubMed

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

2016-12-01

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

Expression optimization and biochemical characterization of a recombinant gamma-glutamyltranspeptidase from Escherichia coli novablue.

PubMed

Yao, Ya-Feng; Weng, Yih-Ming; Hu, Hui-Yu; Ku, Kuo-Lung; Lin, Long-Liu

2006-09-01

A truncated Escherichia coli Novablue gamma-glutamyltranspeptidase (EcGGT) gene lacking the first 48-bp coding sequence for part of the signal sequence was amplified by polymerase chain reaction and cloned into expression vector pQE-30 to generate pQE-EcGGT. The maximum production of His(6)-tagged enzyme by E. coli M15 (pQE-EcGGT) was achieved with 0.1 mM IPTG induction for 12 h at 20 degrees C. The overexpressed enzyme was purified to homogeneity by nickel-chelate chromatography to a specific transpeptidase activity of 4.25 U/mg protein and a final yield of 83%. The molecular masses of the subunits of the purified enzyme were estimated to be 41 and 21 kDa respectively by SDS-PAGE, indicating EcGGT still undergoes the post-translational cleavage even in the truncation of signal sequence. The optimum temperature and pH for the recombinant enzyme were 40 degrees C and 9, respectively. The apparent K (m) and V (max) values for gamma-glutamyl-p-nitroanilide as gamma-glutamyl donor in the transpeptidation reaction were 37.9 microM and 53.7 x 10(-3) mM min(-1), respectively. The synthesis of L -theanine was performed in a reaction mixture containing 10 mM L -Gln, 40 mM ethylamine, and 1.04 U His(6)-tagged EcGGT/ml, pH 10, and a conversion rate of 45% was obtained.

A γ-Glutamyl Cyclotransferase Protects Arabidopsis Plants from Heavy Metal Toxicity by Recycling Glutamate to Maintain Glutathione Homeostasis[C][W

PubMed Central

Paulose, Bibin; Chhikara, Sudesh; Coomey, Joshua; Jung, Ha-il; Vatamaniuk, Olena; Dhankher, Om Parkash

2013-01-01

Plants detoxify toxic metals through a GSH-dependent pathway. GSH homeostasis is maintained by the γ-glutamyl cycle, which involves GSH synthesis and degradation and the recycling of component amino acids. The enzyme γ-glutamyl cyclotransferase (GGCT) is involved in Glu recycling, but the gene(s) encoding GGCT has not been identified in plants. Here, we report that an Arabidopsis thaliana protein with a cation transport regulator-like domain, hereafter referred to as GGCT2;1, functions as γ-glutamyl cyclotransferase. Heterologous expression of GGCT2;1 in Saccharomyces cerevisiae produced phenotypes that were consistent with decreased GSH content attributable to either GSH degradation or the diversion of γ-glutamyl peptides to produce 5-oxoproline (5-OP). 5-OP levels were further increased by the addition of arsenite and GSH to the medium, indicating that GGCT2;1 participates in the cellular response to arsenic (As) via GSH degradation. Recombinant GGCT2;1 converted both GSH and γ-glutamyl Ala to 5-OP in vitro. GGCT2;1 transcripts were upregulated in As-treated Arabidopsis, and ggct2;1 knockout mutants were more tolerant to As and cadmium than the wild type. Overexpression of GGCT2;1 in Arabidopsis resulted in the accumulation of 5-OP. Under As toxicity, the overexpression lines showed minimal changes in de novo Glu synthesis, while the ggct2;1 mutant increased nitrogen assimilation by severalfold, resulting in a very low As/N ratio in tissue. Thus, our results suggest that GGCT2;1 ensures sufficient GSH turnover during abiotic stress by recycling Glu. PMID:24214398

Hepatoprotective effect of Bacoside-A, a major constituent of Bacopa monniera Linn.

PubMed

Sumathi, T; Nongbri, A

2008-10-01

Bacoside-A (B-A) was evaluated for its hepatoprotective activity against d-GalN induced liver injury in rats. B-A is a major constituent isolated from the plant Bacopa monniera Linn. B-A (10mg/kg of body weight) was administered orally once daily for 21 days and then d-GalN (300 mg/kg of body weight) was injected on 21st day after final administration of B-A. B-A reduces the elevated levels of serum alanine transaminase (ALT), aspartate transaminase (AST), alkaline phosphatase (ALP), gamma-glutamyl transferase (gamma-GT), lactate dehydrogenase (LDH), 5'nucleotidase (5'ND). In addition B-A also significantly restored towards normalization of the decreased levels of Vit-C, and Vit-E induced by d-GalN both in liver and plasma. These results suggest that B-A has hepatoprotective effect against d-GalN induced hepatotoxicity in rats.

l-Proline Accumulation and Freeze Tolerance in Saccharomyces cerevisiae Are Caused by a Mutation in the PRO1 Gene Encoding γ-Glutamyl Kinase

PubMed Central

Morita, Yuko; Nakamori, Shigeru; Takagi, Hiroshi

2003-01-01

We previously isolated a mutant which showed a high tolerance to freezing that correlated with higher levels of intracellular l-proline derived from l-proline analogue-resistant mutants. The mutation responsible for the analogue resistance and l-proline accumulation was a single nuclear dominant mutation. By introducing the mutant-derived genomic library into a non-l-proline-utilizing strain, the mutant was found to carry an allele of the wild-type PRO1 gene encoding γ-glutamyl kinase, which resulted in a single amino acid replacement; Asp (GAC) at position 154 was replaced by Asn (AAC). Interestingly, the allele of PRO1 was shown to enhance the activities of γ-glutamyl kinase and γ-glutamyl phosphate reductase, both of which catalyze the first two steps of l-proline synthesis from l-glutamate and which together may form a complex in vivo. When cultured in liquid minimal medium, yeast cells expressing the mutated γ-glutamyl kinase were found to accumulate intracellular l-proline and showed a prominent increase in cell viability after freezing at −20°C compared to the viability of cells harboring the wild-type PRO1 gene. These results suggest that the altered γ-glutamyl kinase results in stabilization of the complex or has an indirect effect on γ-glutamyl phosphate reductase activity, which leads to an increase in l-proline production in Saccharomyces cerevisiae. The approach described in this paper could be a practical method for breeding novel freeze-tolerant yeast strains. PMID:12513997

"Phylogenetic and evolutionary analysis of functional divergence among Gamma glutamyl transpeptidase (GGT) subfamilies".

PubMed

Verma, Ved Vrat; Gupta, Rani; Goel, Manisha

2015-09-14

γ-glutamyltranspeptidase (GGT) is a bi-substrate enzyme conserved in all three domains of life. It catalyzes the cleavage and transfer of γ-glutamyl moiety of glutathione to either water (hydrolysis) or substrates like peptides (transpeptidation). GGTs exhibit great variability in their enzyme kinetics although the mechanism of catalysis is conserved. Recently, GGT has been shown to be a virulence factor in microbes like Helicobacter pylori and Bacillus anthracis. In mammalian cells also, GGT inhibition prior to chemotherapy has been shown to sensitize tumors to the therapy. Therefore, lately both bacterial and eukaryotic GGTs have emerged as potential drug targets, but the efforts directed towards finding suitable inhibitors have not yielded any significant results yet. We propose that delineating the residues responsible for the functional diversity associated with these proteins could help in design of species/clade specific inhibitors. In the present study, we have carried out phylogenetic analysis on a set of 47 GGT-like proteins to address the functional diversity. These proteins segregate into various subfamilies, forming separate clades on the tree. Sequence conservation and motif prediction studies show that even though most of the highly conserved residues have been characterized biochemically in previous studies, a significant number of novel putative sites and motifs are discovered that vary in a clade specific manner. Many of the putative sites predicted during the functional divergence type I and type II analysis, lie close to the known catalytic residues and line the walls of the substrate binding cavity, reinforcing their role in modulating the substrate specificity, catalytic rates and stability of this protein. The study offers interesting insights into the evolution of GGT-like proteins in pathogenic vs. non-pathogenic bacteria, archaea and eukaryotes. Our analysis delineates residues that are highly specific to each GGT subfamily. We propose

The gamma-glutamyl transpeptidase to platelet ratio (GPR) predicts significant liver fibrosis and cirrhosis in patients with chronic HBV infection in West Africa.

PubMed

Lemoine, Maud; Shimakawa, Yusuke; Nayagam, Shevanthi; Khalil, Mustapha; Suso, Penda; Lloyd, Jo; Goldin, Robert; Njai, Harr-Freeya; Ndow, Gibril; Taal, Makie; Cooke, Graham; D'Alessandro, Umberto; Vray, Muriel; Mbaye, Papa Saliou; Njie, Ramou; Mallet, Vincent; Thursz, Mark

2016-08-01

Simple and inexpensive non-invasive fibrosis tests are highly needed but have been poorly studied in sub-Saharan Africa. Using liver histology as a gold standard, we developed a novel index using routine laboratory tests to predict significant fibrosis in patients with chronic HBV infection in The Gambia, West Africa. We prospectively assessed the diagnostic accuracy of the novel index, Fibroscan, aspartate transaminase-to-platelet ratio index (APRI), and Fib-4 in Gambian patients with CHB (training set) and also in French and Senegalese CHB cohorts (validation sets). Of 135 consecutive treatment-naïve patients with CHB who had liver biopsy, 39% had significant fibrosis (Metavir fibrosis stage ≥F2) and 15% had cirrhosis (F4). In multivariable analysis, gamma-glutamyl transpeptidase (GGT) and platelet count were independent predictors of significant fibrosis. Consequently, GGT-to-platelet ratio (GPR) was developed. In The Gambia, the area under the receiver operating characteristic curve (AUROC) of the GPR was significantly higher than that of APRI and Fib-4 to predict ≥F2, ≥F3 and F4. In Senegal, the AUROC of GPR was significantly better than Fib-4 and APRI for ≥F2 (0.73, 95% CI 0.59 to 0.86) and better than Fib-4 and Fibroscan for ≥F3 (0.93, 0.87 to 0.99). In France, the AUROC of GPR to diagnose ≥F2 (0.72, 95% CI 0.59 to 0.85) and F4 (0.87, 0.76 to 0.98) was equivalent to that of APRI and Fib-4. The GPR is a more accurate routine laboratory marker than APRI and Fib-4 to stage liver fibrosis in patients with CHB in West Africa. The GPR represents a simple and inexpensive alternative to liver biopsy and Fibroscan in sub-Saharan Africa. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Human γ-glutamyl transpeptidase 1: Structures of the free enzyme, inhibitor-bound tetrahedral transition states, and glutamate-bound enzyme reveal novel movement within the active site during catalysis [Human gamma-glutamyl transpeptidase: Inhibitor binding and movement within the active site

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

Terzyan, Simon S.; Burgett, Anthony W. G.; Heroux, Annie

γ-Glutamyl transpeptidase 1 (GGT1) is a cell surface, N-terminal nucleophile hydrolase that cleaves glutathione and other γ-glutamyl compounds. GGT1 expression is essential in cysteine homeostasis, and its induction has been implicated in the pathology of asthma, reperfusion injury, and cancer. In this study, we report four new crystal structures of human GGT1 (hGGT1) that show conformational changes within the active site as the enzyme progresses from the free enzyme to inhibitor-bound tetrahedral transition states and finally to the glutamate-bound structure prior to the release of this final product of the reaction. The structure of the apoenzyme shows flexibility within themore » active site. The serine-borate-bound hGGT1 crystal structure demonstrates that serine-borate occupies the active site of the enzyme, resulting in an enzyme-inhibitor complex that replicates the enzyme's tetrahedral intermediate/transition state. The structure of GGsTop-bound hGGT1 reveals its interactions with the enzyme and why neutral phosphonate diesters are more potent inhibitors than monoanionic phosphonates. These structures are the first structures for any eukaryotic GGT that include a molecule in the active site covalently bound to the catalytic Thr-381. The glutamate-bound structure shows the conformation of the enzyme prior to release of the final product and reveals novel information regarding the displacement of the main chain atoms that form the oxyanion hole and movement of the lid loop region when the active site is occupied. Lastly,tThese data provide new insights into the mechanism of hGGT1-catalyzed reactions and will be invaluable in the development of new classes of hGGT1 inhibitors for therapeutic use.« less

Human γ-glutamyl transpeptidase 1: Structures of the free enzyme, inhibitor-bound tetrahedral transition states, and glutamate-bound enzyme reveal novel movement within the active site during catalysis [Human gamma-glutamyl transpeptidase: Inhibitor binding and movement within the active site

DOE PAGES

Terzyan, Simon S.; Burgett, Anthony W. G.; Heroux, Annie; ...

2015-05-26

γ-Glutamyl transpeptidase 1 (GGT1) is a cell surface, N-terminal nucleophile hydrolase that cleaves glutathione and other γ-glutamyl compounds. GGT1 expression is essential in cysteine homeostasis, and its induction has been implicated in the pathology of asthma, reperfusion injury, and cancer. In this study, we report four new crystal structures of human GGT1 (hGGT1) that show conformational changes within the active site as the enzyme progresses from the free enzyme to inhibitor-bound tetrahedral transition states and finally to the glutamate-bound structure prior to the release of this final product of the reaction. The structure of the apoenzyme shows flexibility within themore » active site. The serine-borate-bound hGGT1 crystal structure demonstrates that serine-borate occupies the active site of the enzyme, resulting in an enzyme-inhibitor complex that replicates the enzyme's tetrahedral intermediate/transition state. The structure of GGsTop-bound hGGT1 reveals its interactions with the enzyme and why neutral phosphonate diesters are more potent inhibitors than monoanionic phosphonates. These structures are the first structures for any eukaryotic GGT that include a molecule in the active site covalently bound to the catalytic Thr-381. The glutamate-bound structure shows the conformation of the enzyme prior to release of the final product and reveals novel information regarding the displacement of the main chain atoms that form the oxyanion hole and movement of the lid loop region when the active site is occupied. Lastly,tThese data provide new insights into the mechanism of hGGT1-catalyzed reactions and will be invaluable in the development of new classes of hGGT1 inhibitors for therapeutic use.« less

Blood plasma chemistries from wild mourning doves held in captivity.

PubMed

Schulz, J H; Bermudez, A J; Tomlinson, J L; Firman, J D; He, Z

2000-07-01

Despite the extensive amount of research conducted on mourning doves (Zenaida macroura), no biochemical reference values exist for this species. Our objective, therefore, was to establish base line clinical chemistry reference values for mourning doves to assist with establishing clinical diagnoses. Wild mourning doves were captured 19 March 1996 to 8 August 1996, and 6 February 1998 to 12 May 1998; blood samples were collected from 382 mourning doves. Plasma biochemical values were established for glucose, sodium, potassium, chloride, enzymatic CO2, albumin, total protein, globulin, calcium, phosphorus, cholesterol, magnesium, aspartate aminotransferase (AST), gamma glutamyl transferase (GGT), lactate dehydrogenase (LDH), and uric acid. These reference values are invaluable for determining diagnosis of diseases of the gastrointestinal, hepatic, renal, cardiovascular, musculoskeletal, and endocrine systems.

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

PubMed Central

Ramsay, Emma E.; Dilda, Pierre J.

2014-01-01

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

Study of enzyme activities in the descending part of the duodenum in patients of duodenal ulcer.

PubMed

Fernandes, V L C; Bhasin, D K; Rana, S V

2006-03-01

The aim of this study was to measure the levels of lactase, sucrase, maltase, leucine amino peptidase and gamma-glutamyl transpeptidase in duodenum of Indian patients with duodenal ulcer. The effect of duodenum inflammation on these brush border enzymes has also been analysed in this study. Levels of lactase, sucrase, maltase, leucine amino peptidase and gamma-glutamyl transpeptidase were assessed in duodenal biopsies of 20 patients of duodenal ulcer and 20 non-ulcer dyspepsia. The duodenal biopsy specimens were also examined histopathologically for presence or absence of inflammation. There was no significant difference (p>0.05) in the activity of above mentioned enzyme levels in both the groups. Only levels of gamma-glutamyl transpeptidase were significantly decreased in patients of duodenal ulcer with duodenal inflammation. This study shows that only the levels of gamma-glutamyl transpeptidase were significantly decreased in patients of duodenal ulcer with inflammation but no change in duodenal enzymes due to duodenal ulcer as compared to non-ulcer dyspepsia.

Mammalian proapoptotic factor ChaC1 and its homologues function as γ-glutamyl cyclotransferases acting specifically on glutathione

PubMed Central

Kumar, Akhilesh; Tikoo, Shweta; Maity, Shuvadeep; Sengupta, Shantanu; Sengupta, Sagar; Kaur, Amandeep; Kumar Bachhawat, Anand

2012-01-01

ChaC1 is a mammalian proapoptic protein of unknown function induced during endoplasmic reticulum stress. We show using in vivo studies and novel in vitro assays that the ChaC family of proteins function as γ-glutamyl cyclotransferases acting specifically to degrade glutathione but not other γ-glutamyl peptides. The overexpression of these proteins (but not the catalytically dead E>Q mutants) led to glutathione depletion and enhanced apoptosis in yeast. The ChaC family is conversed across all phyla and represents a new pathway for glutathione degradation in living cells, and the first cytosolic pathway for glutathione degradation in mammalian cells. PMID:23070364

Identification and clarification of the role of key active site residues in bacterial glutathione S-transferase zeta/maleylpyruvate isomerase

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

Fang, Ti; Li, De-Feng; Zhou, Ning-Yi, E-mail: n.zhou@pentium.whiov.ac.cn

2011-07-08

Highlights: {yields} Application of site-directed mutagenesis to probe the active site residues of glutathione-dependent maleylpyruvate isomerase. {yields} Two conserved residues, Arg8 and Arg176, in zeta class glutathione S-transferases are critical for maleylpyruvate orientation and enolization. {yields} Arg109, found exclusively in NagL, participates in k{sub cat} regulation. {yields} The T11A mutant exhibited a significantly decreased K{sub m} value for glutathione with little impact on maleylpyruvate kinetics. {yields} The Thr11 residue appears to have significance in the evolution of glutathione S-transferase classes. -- Abstract: The maleylpyruvate isomerase NagL from Ralstonia sp. strain U2, which has been structurally characterized previously, catalyzes the isomerizationmore » of maleylpyruvate to fumarylpyruvate. It belongs to the class zeta glutathione S-transferases (GSTZs), part of the cytosolic GST family (cGSTs). In this study, site-directed mutagenesis was conducted to probe the functions of 13 putative active site residues. Steady-state kinetic information for mutants in the reduced glutathione (GSH) binding site, suggested that (a) Gln64 and Asp102 interact directly with the glutamyl moiety of glutathione, (b) Gln49 and Gln64 are involved in a potential electron-sharing network that influences the ionization of the GSH thiol. The information also suggests that (c) His38, Asn108 and Arg109 interact with the GSH glycine moiety, (d) His104 has a role in the ionization of the GSH sulfur and the stabilization of the maleyl terminal carboxyl group in the reaction intermediate and (e) Arg110 influences the electron distribution in the active site and therefore the ionization of the GSH thiolate. Kinetic data for mutants altered in the substrate-binding site imply that (a) Arg8 and Arg176 are critical for maleylpyruvate orientation and enolization, and (b) Arg109 (exclusive to NagL) participates in k{sub cat} regulation. Surprisingly, the T11A mutant

The effect of silymarin on hepatic regeneration after partial hepatectomy: is silymarin effective in hepatic regeneration?

PubMed Central

Cetinkunar, Suleyman; Tokgoz, Serhat; Bilgin, Bulent Caglar; Erdem, Hasan; Aktimur, Recep; Can, Serpil; Erol, Huseyin Serkan; Isgoren, Atilla; Sozen, Selim; Polat, Yilmaz

2015-01-01

Aim: Silymarin from Silybum marianum was found to reduce liver injury. The aim of the present study was to investigate the effects of silymarin on hepatic regeneration in partially hepatectomized rats. Methods: Thirty Wistar-Albino rats were divided into 3 groups of 10 animals as sham, control and experimental groups. In the sham group (n=10) abdominal incision was closed after laparotomy. In the control group (n=10), the rats underwent 70% hepatectomy after laparotomy. In the experimental group (n=10) after partial 70% hepatectomy, silymarin (200 mg/kg/d) were given to rats for 10 days. Rats in three groups were sacrificed on 10 days. Aspartate (AST) and alanine transaminase (ALT), gamma glutamyl transferase (GGT), ALP, LDH and total bilirubin levels were measured using intracardiac blood samples. Tissue malondialdehyde (MDA) and tissue glutathion (GSH) and Superoxide dismutase (SOD) levels were measured. To reveal the increase in the mass of the remnant liver tissue in the control and experimental groups relative weight of the liver was calculated. Histopathological analysis of the liver was performed using a semi-quantitative scoring system. Results: A statistically significant difference among three groups was not shown for AST and ALT levels. A statistically significant difference was found between the groups as for total bilirubin and gamma glutamyl transferase levels. Increases in relative liver weights were seen with time in Groups 2 and 3. A statistically significant difference was not found for tissue malondialdehyde, Glutathion and Superoxide dismutase levels between hepatectomy and hepatectomy + silymarin groups. On liver tissue sections of the rats in the hepatectomy + silymarin group, increased regeneration and lipid peroxidation were observed accompanied by decreased antioxidant response. Conclusion: It has been observed that silymarin with many established functions such as antiproliferative, anti-inflammatory and energy antioxidant effects, does

Evaluation of coagulation parameters and liver enzymes among alcohol drinkers in Port Harcourt, Nigeria.

PubMed

Adias, Teddy Charles; Egerton, Everton; Erhabor, Osaro

2013-01-01

Alcohol is a major contributor to the global burden of disease, disability, and death in high, middle, and low-income countries. Harmful use of alcohol is one of the main factors contributing to premature deaths and avoidable disease burden worldwide and has a major impact on public health. The aim of this present cross-sectional study was to investigate the effect of alcohol consumption on coagulation parameters and liver enzymes of subjects in Port Harcourt, Nigeria. Two hundred adults consisting of 120 alcohol dependent subjects and 80 age, gender-matched nondrinkers aged 25-65 years (mean age 45.25 ± 11.50 years) were enrolled in this study. Of the 120 chronic alcohol drinkers, 37 were dependent on local dry gin, while 83 were dependent on other alcoholic beverages. The mean values of the liver enzymes, aspartate aminotransferase and gamma glutamyl transferase, were significantly higher (P = 0.002 and P = 0.02 respectively) among the chronic alcohol consumers compared with their nondrinker counterparts. Although the value of alanine aminotransferase was higher in the chronic drinkers, it did not reveal any significant difference (P = 0.11). The coagulation parameters, prothrombin time and activated partial thromboplastin time were investigated among chronic drinkers and nondrinkers. The mean value of prothrombin time and activated partial thromboplastin time was significantly higher in the chronic alcohol drinkers compared to the nondrinkers (P = 0.04 and P = 0.02 respectively). We observed a positive and significant correlation between values of liver enzymes, serum gamma glutamyl transferase and aspartate aminotransferase, and values of prothrombin time among alcohol consumers (r = 0.72 and r = 0.68 respectively). The implementation of policies to target harm reduction strategies among alcoholics is urgently needed, alongside the building of a strong base of public awareness and community support required for the continuity and sustainability of alcohol

Evaluation of coagulation parameters and liver enzymes among alcohol drinkers in Port Harcourt, Nigeria

PubMed Central

Adias, Teddy Charles; Egerton, Everton; Erhabor, Osaro

2013-01-01

Alcohol is a major contributor to the global burden of disease, disability, and death in high, middle, and low-income countries. Harmful use of alcohol is one of the main factors contributing to premature deaths and avoidable disease burden worldwide and has a major impact on public health. The aim of this present cross-sectional study was to investigate the effect of alcohol consumption on coagulation parameters and liver enzymes of subjects in Port Harcourt, Nigeria. Two hundred adults consisting of 120 alcohol dependent subjects and 80 age, gender-matched nondrinkers aged 25–65 years (mean age 45.25 ± 11.50 years) were enrolled in this study. Of the 120 chronic alcohol drinkers, 37 were dependent on local dry gin, while 83 were dependent on other alcoholic beverages. The mean values of the liver enzymes, aspartate aminotransferase and gamma glutamyl transferase, were significantly higher (P = 0.002 and P = 0.02 respectively) among the chronic alcohol consumers compared with their nondrinker counterparts. Although the value of alanine aminotransferase was higher in the chronic drinkers, it did not reveal any significant difference (P = 0.11). The coagulation parameters, prothrombin time and activated partial thromboplastin time were investigated among chronic drinkers and nondrinkers. The mean value of prothrombin time and activated partial thromboplastin time was significantly higher in the chronic alcohol drinkers compared to the nondrinkers (P = 0.04 and P = 0.02 respectively). We observed a positive and significant correlation between values of liver enzymes, serum gamma glutamyl transferase and aspartate aminotransferase, and values of prothrombin time among alcohol consumers (r = 0.72 and r = 0.68 respectively). The implementation of policies to target harm reduction strategies among alcoholics is urgently needed, alongside the building of a strong base of public awareness and community support required for the continuity and sustainability of alcohol

Is gamma-glutamyl transpeptidase a biomarker for oxidative stress in periodontitis?

PubMed Central

Sreeram, Meenakshi; Suryakar, Adinath Narayan; Dani, Nitin Hemchandra

2015-01-01

Context: Periodontal disease and oxidative stress (OS) are part of a vicious cycle with each causing a deleterious effect on the other causing changes in the levels of antioxidants, and enzymes of antioxidant defense. Biomarkers and methods used for measuring OS are very expensive. Aims: To see how gamma-glutamyltransferase (GGT) fares, as a biomarker for OS in periodontits along with other routinely used biomarkers. Design: A cross-sectional study involving 300 people of which 150 were cases and 150 were controls. Setting: Candidates enrolled were patients visiting the OPD of MGV's Dental College and Hospital, Nasik, India between January 2011 and December 2012. Materials and Methods: Serum samples of patients with periodontitis, and controls were analyzed for malondialdehyde, superoxide dismutase (SOD), glutathione peroxidase (GPx), uric acid, and GGT. Statistical Analysis Used: Analysis was performed using Student's t test. P <0.05 were considered to be significant. Results: Malondialdehyde values were found to be significantly higher cases, while SOD, GPx and uric acid levels were found to be lower than controls. GGT levels were significantly higher in cases as compared to controls. Conclusions: GGT may be used as a cheap, quick, easy and precise marker for measuring OS. PMID:26015663

Hepatoprotective activity of Tridax procumbens against d-galactosamine/lipopolysaccharide-induced hepatitis in rats.

PubMed

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

2005-10-03

The hepatoprotective activity of aerial parts of Tridax procumbens was investigated against d-Galactosamine/Lipopolysaccharide (d-GalN/LPS) induced hepatitis in rats. d-GalN/LPS (300 mg/kg body weight/30 microg/kg body weight)-induced hepatic damage was manifested by a significant increase in the activities of marker enzymes (aspartate transaminase, alanine transaminase, alkaline phosphatase, lactate dehydrogenase and gamma glutamyl transferase) and bilirubin level in serum and lipids both in serum and liver. Pretreatment of rats with a chloroform insoluble fraction from ethanolic extract of Tridax procumbens reversed these altered parameters to normal values. The biochemical observations were supplemented by histopathological examination of liver sections. Results of this study revealed that Tridax procumbens could afford a significant protection in the alleviation of d-GalN/LPS-induced hepatocellular injury.

Characterization of acute undifferentiated leukemia by combined analysis of plasma membrane-associated gamma-glutamyltranspeptidase and soluble terminal transferase.

PubMed

Heumann, D; Losa, G; Barras, C; Morell, A; von Fliedner, V

1985-08-01

gamma-Glutamyltranspeptidase (gamma-GT) is a plasma membrane-associated enzyme present in blasts of certain acute leukemias. We analyzed 90 cases of undifferentiated and differentiated acute leukemias for gamma-GT, using a colorimetric assay. Blasts of all patients with common acute lymphoblastic leukemia (ALL) and T-ALL were negative for gamma-GT (less than 5 units). In contrast, gamma-GT was significantly elevated in acute myeloblastic or monoblastic leukemia blasts (P less than .001). In 16 cases of acute undifferentiated leukemia (AUL) studied, the levels of gamma-GT ranged from 0 to 93 units; in eight cases, gamma-GT was positive (greater than 5 units), and six of these had 2% to 5% Sudan black-positive leukemic cells in the blast-enriched suspension. Combined gamma-GT/TdT analysis revealed that both enzyme markers were mutually exclusive in 75% of AUL cases, suggesting that gamma-GT+/TdT-blasts are of nonlymphoid origin, and gamma-GT-/TdT+ blasts are of lymphoid origin. Two cases were devoid of both enzyme activities and could represent truly undifferentiated leukemia. Thus, combined gamma-GT/TdT analysis underlines the heterogeneity of AUL and appears to be useful in defining the lineage commitment of undifferentiated leukemic blasts.

γ-Glutamyl transpeptidase has a role in the persistent colonization of the avian gut by Campylobacter jejuni

PubMed Central

Barnes, If H.A.; Bagnall, Mary C.; Browning, Darren D.; Thompson, Stuart A.; Manning, Georgina; Newell, Diane G.

2009-01-01

The contribution of γ-glutamyl transpeptidase (GGT) to Campylobacter jejuni virulence and colonization of the avian gut has been investigated. The presence of the ggt gene in C. jejuni strains directly correlated with the expression of GGT activity as measured by cleavage and transfer of the γ-glutamyl moiety. Inactivation of the monocistronic ggt gene in C. jejuni strain 81116 resulted in isogenic mutants with undetectable GGT activity; nevertheless, these mutants grew normally in vitro. However, the mutants had increased motility, a 5.4-fold higher invasion efficiency into INT407 cells in vitro and increased resistance to hydrogen peroxide stress. Moreover, the apoptosis-inducing activity of the ggt mutant was significantly lower than that of the parental strain. In vivo studies showed that, although GGT activity was not required for initial colonization of 1-day-old chicks, the enzyme was required for persistant colonization of the avian gut. PMID:17600669

Glutathione Synthetase Deficiency, an Inborn Error of Metabolism Involving the γ-Glutamyl Cycle in Patients with 5-Oxoprolinuria (Pyroglutamic Aciduria)

PubMed Central

Wellner, Vaira P.; Sekura, Ronald; Meister, Alton; Larsson, Agne

1974-01-01

Enzyme studies on placenta, cultured skin fibroblasts, and erythrocytes from two sisters with the inborn error 5-oxoprolinuria (pyroglutamic aciduria) indicate that the metabolic lesion in this disease is at the glutathione synthetase (EC 6.3.2.3) step of the γ-glutamyl cycle. Excessive urinary excretion of 5-oxoproline by these patients appears to be associated with increased synthesis of γ-glutamyl-cysteine and formation of 5-oxoproline from this dipeptide. Thus, 5-oxoproline is produced in amounts that exceed the normal capacity of 5-oxoprolinase to convert it to glutamate. The data indicate that it may be possible to identify individuals who are heterozygous for this trait by determinations of erythrocyte glutathione synthetase. PMID:4152248

21 CFR 862.1535 - Ornithine carbamyl transferase test system.

Code of Federal Regulations, 2011 CFR

2011-04-01

... Test Systems § 862.1535 Ornithine carbamyl transferase test system. (a) Identification. An ornithine carbamyl transferase test system is a device intended to measure the activity of the enzyme ornithine... and treatment of liver diseases, such as infectious hepatitis, acute cholecystitis (inflammation of...

Hepatoprotective Effect of Citral on Acetaminophen-Induced Liver Toxicity in Mice.

PubMed

Uchida, Nancy Sayuri; Silva-Filho, Saulo Euclides; Cardia, Gabriel Fernando Esteves; Cremer, Edivaldo; Silva-Comar, Francielli Maria de Souza; Silva, Expedito Leite; Bersani-Amado, Ciomar Aparecida; Cuman, Roberto Kenji Nakamura

2017-01-01

High doses of acetaminophen (APAP) lead to acute liver damage. In this study, we evaluated the effects of citral in a murine model of hepatotoxicity induced by APAP. The liver function markers alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), and gamma-glutamyl transferase ( γ GT) were determined to evaluate the hepatoprotective effects of citral. The livers were used to determine myeloperoxidase (MPO) activity and nitric oxide (NO) production and in histological analysis. The effect of citral on leukocyte migration and antioxidant activity was evaluated in vitro. Citral pretreatment decreased significantly the levels of ALT, AST, ALP, and γ GT, MPO activity, and NO production. The histopathological analysis showed an improvement of hepatic lesions in mice after citral pretreatment. Citral inhibited neutrophil migration and exhibited antioxidant activity. Our results suggest that citral protects the liver against liver toxicity induced by APAP.

Redifferentiation of human hepatoma cells (SMMC-7721) induced by two new highly oxygenated bisabolane-type sesquiterpenes.

PubMed

Miao, Ruidong; Wei, Juan; Zhang, Qi; Sajja, Venkateswara; Yang, Jinbo; Wang, Qin

2008-12-01

Bisabolane-type sesquiterpenes are a class of biologically active compounds that has antitumour,antifungal, antibacterial,antioxidant and antivenom properties.We investigated the effect of two new highly oxygenated bisabolane-type sesquiterpenes (HOBS)isolated from Cremanthodium discoideum (C.discoideum) on tumour cells. Our results showed that HOBS induced morphological differentiation and reduced microvilli formation on the cell surface in SMMC-7721 cells.Flow cytometry analysis demonstrated that HOBS could induce cell-cycle arrest in the G1 phase. Moreover,HOBS was able to increase tyrosine-alpha ketoglutarate transaminase activity,decrease alpha- foetoprotein level and gamma-glutamyl transferase activity. In addition,we found that HOBS inhibited the anchorage- independent growth of SMMC-7721 cells in a dose-dependent manner.Taken together,all the above observations indicate that HOBS might be able to normalize malignant SMMC-7721 cells by inhibiting cell proliferation and inducing redifferentiation.

21 CFR 862.1535 - Ornithine carbamyl transferase test system.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Ornithine carbamyl transferase test system. 862.1535 Section 862.1535 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... Test Systems § 862.1535 Ornithine carbamyl transferase test system. (a) Identification. An ornithine...

21 CFR 862.1535 - Ornithine carbamyl transferase test system.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Ornithine carbamyl transferase test system. 862.1535 Section 862.1535 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... Test Systems § 862.1535 Ornithine carbamyl transferase test system. (a) Identification. An ornithine...

Polymorphisms of glutathione S-transferase Mu 1, glutathione S-transferase theta 1 and glutathione S-transferase Pi 1 genes in Hodgkin's lymphoma susceptibility and progression.

PubMed

Lourenço, Gustavo J; Néri, Iramaia A; Sforni, Vitor C S; Kameo, Rodolfo; Lorand-Metze, Irene; Lima, Carmen S P

2009-06-01

We tested in this study whether the polymorphisms of the glutathione S-transferase Mu1 (GSTM1), glutathione S-transferase Theta 1 (GSTT1) and glutathione S-transferase Pi 1 (GSTP1), involved in metabolism of chemical agents, cell proliferation and cell survival, alter the risk for Hodgkin lymphoma (HL). Genomic DNA from 110 consecutive patients with HL and 226 controls was analysed by polymerase chain reaction and restriction digestion for the polymorphism analyses. Similar frequencies of the GSTM1 and GSTT1 genotypes were seen in patients and controls. In contrast, the frequency of the GSTP1 wild genotype (59.1%versus 36.3%, P = 0.004) was higher in patients than in controls. Individuals with the wild genotype had a 2.68 (95%CI: 1.38-5.21)-fold increased risk for the disease than others. An excess of the GSTP1 wild genotype was also observed in patients with tumors of stages III + IV when compared with those with tumors of stages I + II (39.1%versus 20.0%, P = 0.03). These results suggest that the wild allele of the GSTP1 gene is linked to an increased risk and high aggressiveness of the HL in our cases but they should be confirmed by further studies with larger cohorts of patients and controls.

Identification and Characterization of γ-Glutamylamine Cyclotransferase, an Enzyme Responsible for γ-Glutamyl-ϵ-lysine Catabolism*

PubMed Central

Oakley, Aaron J.; Coggan, Marjorie; Board, Philip G.

2010-01-01

γ-Glutamylamine cyclotransferase (GGACT) is an enzyme that converts γ-glutamylamines to free amines and 5-oxoproline. GGACT shows high activity toward γ-glutamyl-ϵ-lysine, derived from the breakdown of fibrin and other proteins cross-linked by transglutaminases. The enzyme adopts the newly identified cyclotransferase fold, observed in γ-glutamylcyclotransferase (GGCT), an enzyme with activity toward γ-glutamyl-α-amino acids (Oakley, A. J., Yamada, T., Liu, D., Coggan, M., Clark, A. G., and Board, P. G. (2008) J. Biol. Chem. 283, 22031–22042). Despite the absence of significant sequence identity, several residues are conserved in the active sites of GGCT and GGACT, including a putative catalytic acid/base residue (GGACT Glu82). The structure of GGACT in complex with the reaction product 5-oxoproline provides evidence for a common catalytic mechanism in both enzymes. The proposed mechanism, combined with the three-dimensional structures, also explains the different substrate specificities of these enzymes. Despite significant sequence divergence, there are at least three subfamilies in prokaryotes and eukaryotes that have conserved the GGCT fold and GGCT enzymatic activity. PMID:20110353

Accumulation of 5-Oxoproline in Mouse Tissues After Inhibition of 5-Oxoprolinase and Administration of Amino Acids: Evidence for Function of the γ-Glutamyl Cycle*

PubMed Central

Van Der Werf, Paul; Stephani, Ralph A.; Meister, Alton

1974-01-01

5-Oxoprolinase catalyzes the conversion of 5-oxo-L-proline (L-pyroglutamate, L-2-pyrrolidone-5-carboxylate) to L-glutamate with concomitant stoichiometric cleavage of ATP to ADP and inorganic orthophosphate. In this reaction, a step in the γ-glutamyl cycle, 5-oxoproline (formed by the action of γ-glutamylcyclotransferase on γ-glutamyl amino acids, which are in turn formed by transpeptidation of amino acids with glutathione), is made available for glutathione synthesis. When mice are injected with L-2-imidazolidone-4-carboxylate, a competitive inhibitor of 5-oxoprolinase, they accumulate 5-oxoproline in their tissues (kidney, liver, brain, and eye) and excrete it in the urine. Mice given the inhibitor together with one of several L-amino acids accumulate and excrete much more 5-oxoproline than when they are given the inhibitor alone. Such augmentation of 5-oxoproline accumulation offers evidence for the function of the γ-glutamyl cycle in vivo and supports the view that 5-oxoproline is a quantitatively significant metabolite. Images PMID:4151516

EFFICIENCY OF BORAGE SEEDS OIL AGAINST GAMMA IRRADIATION-INDUCED HEPATOTOXICITY IN MALE RATS: POSSIBLE ANTIOXIDANT ACTIVITY.

PubMed

Khattab, Hala A H; Abdallah, Inas Z A; Yousef, Fatimah M; Huwait, Etimad A

2017-01-01

Borage ( Borago officinal L.) is an annual herbaceous plant of great interest because its oil contains a high percentage of γ-linolenic acid (GLA). The present work was carried out to detect fatty acids composition of the oil extracted from borage seeds (BO) and its potential effectiveness against γ-irradiation- induced hepatotoxicity in male rats. GC-MS analysis of fatty acids methyl esters of BO was performed to identify fatty acids composition. Sixty rats were divided into five groups (12 rats each): Control, irradiated; rats were exposed to (6.5 Gy) of whole body γ-radiation, BO (50 mg/kg b.wt), irradiated BO post-treated and irradiated BO prepost-treated. Six rats from each group were sacrificed at two time intervals 7 and 15 days post-irradiation. Serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), gamma glutamyl transferase (GGT) levels, lipids profile, as well as serum and hepatic reduced glutathione (GSH) and lipid peroxide (malondialdehyde) (MDA) levels were assessed. Histopathological examination of liver sections were also carried out. The results showed that the high contents of BO extracted by cold pressing, were linoleic acid (34.23%) and GLA (24.79%). Also, oral administration of BO significantly improved serum levels of liver enzymes, lipids profile, as well as serum and hepatic GSH and MDA levels (p<0.001) as compared with irradiated rats after 15 days post irradiation. Moreover, it exerted marked amelioration against irradiation-induced histopathological changes in liver tissues. The improvement was more pronounced in irradiated BO prepost-treated group than irradiated BO post-treated. BO has a beneficial role in reducing hepatotoxicity and oxidative stress induced by radiation exposure. Therefore, BO may be used as a beneficial supplement for patients during radiotherapy treatment.

Southern Analysis of Genomic Alterations in Gamma-Ray-Induced Aprt- Hamster Cell Mutants

PubMed Central

Grosovsky, Andrew J.; Drobetsky, Elliot A.; deJong, Pieter J.; Glickman, Barry W.

1986-01-01

The role of genomic alterations in mutagenesis induced by ionizing radiation has been the subject of considerable speculation. By Southern blotting analysis we show here that 9 of 55 (approximately 1/6) gamma-ray-induced mutants at the adenine phosphoribosyl transferase (aprt) locus of Chinese hamster ovary (CHO) cells have a detectable genomic rearrangement. These fall into two classes: intragenic deletions and chromosomal rearrangements. In contrast, no major genomic alterations were detected among 67 spontaneous mutants, although two restriction site loss events were observed. Three gamma-ray-induced mutants were found to be intragenic deletions; all may have identical break-points. The remaining six gamma-ray-induced mutants demonstrating a genomic alteration appear to be the result of chromosomal rearrangements, possibly translocation or inversion events. None of the remaining gamma-ray-induced mutants showed any observable alteration in blotting pattern indicating a substantial role for point mutation in gamma-ray-induced mutagenesis at the aprt locus. PMID:3013724

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

PubMed

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

2005-01-01

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

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

PubMed Central

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

1987-01-01

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

Hepatoprotective Effect of Citral on Acetaminophen-Induced Liver Toxicity in Mice

PubMed Central

Silva-Filho, Saulo Euclides; Cardia, Gabriel Fernando Esteves; Cremer, Edivaldo; Bersani-Amado, Ciomar Aparecida

2017-01-01

High doses of acetaminophen (APAP) lead to acute liver damage. In this study, we evaluated the effects of citral in a murine model of hepatotoxicity induced by APAP. The liver function markers alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), and gamma-glutamyl transferase (γGT) were determined to evaluate the hepatoprotective effects of citral. The livers were used to determine myeloperoxidase (MPO) activity and nitric oxide (NO) production and in histological analysis. The effect of citral on leukocyte migration and antioxidant activity was evaluated in vitro. Citral pretreatment decreased significantly the levels of ALT, AST, ALP, and γGT, MPO activity, and NO production. The histopathological analysis showed an improvement of hepatic lesions in mice after citral pretreatment. Citral inhibited neutrophil migration and exhibited antioxidant activity. Our results suggest that citral protects the liver against liver toxicity induced by APAP. PMID:28717379

Bilateral renal dysplasia with nephron hypoplasia in a foal.

PubMed

Zicker, S C; Marty, G D; Carlson, G P; Madigan, J E; Smith, J M; Goetzman, B W

1990-06-15

Bilateral renal dysplasia and nephron hypoplasia was diagnosed in a Quarter Horse foal with clinical signs of lethargy, convulsions, and diarrhea. Laboratory evaluation revealed anemia, hypoproteinemia, leukopenia, hyponatremia, hypochloremia, and hyposmolality. The foal also had high concentrations of serum creatinine, BUN, and phosphorus. Evaluation of urinary indices revealed a high ratio of urinary gamma-glutamyl-transferase activity to concentration of creatinine, as well as a high fractional clearance ratio of sodium and potassium. Intravenous treatment with saline solution (0.9% NaCl) and antimicrobials provided only temporary resolution of some of the abnormalities. Diagnosis was partly established by histologic evaluation of renal tissue obtained via an ultrasonographically guided biopsy and was confirmed at necropsy. Pathologic changes in the kidney were unique in that the size of the kidneys, along with the appearance and number of glomeruli, were essentially normal despite marked hypoplasia of nephron tubules in the medulla.

Gamma-glutamyl transpeptidase (GGT) blood test

MedlinePlus

... test is used to detect diseases of the liver or bile ducts. It is also done with other tests (such ... and bilirubin tests) to tell the difference between liver or bile duct disorders and bone disease. It may also be ...

Spectrofluorimetric assay method for glutathione and glutathione transferase using monobromobimane.

PubMed

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

2011-06-01

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

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

PubMed Central

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

1984-01-01

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

Improved expression, purification and crystallization of a putative N-acetyl-γ-glutamyl-phosphate reductase from rice (Oryza sativa)

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

Miura-Ohnuma, Jun; Nonaka, Tsuyoshi; Katoh, Shizue

2005-12-01

Crystals of OsAGPR were obtained using the sitting-drop vapour-diffusion method at 293 K and diffract X-rays to at least 1.8 Å resolution. They belong to the hexagonal space group P6{sub 1}, with unit-cell parameters a = 86.11, c = 316.3 Å. N-Acetyl-γ-glutamyl-phosphate reductase (AGPR) catalyzes the third step in an eight-step arginine-biosynthetic pathway that starts with glutamate. This enzyme converts N-acetyl-γ-glutamyl phosphate to N-acetylglutamate-γ-semialdehyde by an NADPH-dependent reductive dephosphorylation. AGPR from Oryza sativa (OsAGPR) was expressed in Escherichia coli at 291 K as a soluble fusion protein with an upstream thioredoxin-hexahistidine [Trx-(His){sub 6}] extension. OsAGPR(Ala50–Pro366) was purified and crystals weremore » obtained using the sitting-drop vapour-diffusion method at 293 K and diffract X-rays to at least 1.8 Å resolution. They belong to the hexagonal space group P6{sub 1}, with unit-cell parameters a = 86.11, c = 316.3 Å.« less

Blood biochemistry reference values for wild juvenile loggerhead sea turtles (Caretta caretta) from Madeira archipelago.

PubMed

Delgado, Cláudia; Valente, Ana; Quaresma, Isabel; Costa, Margarida; Dellinger, Thomas

2011-07-01

Standard biochemical parameters were determined in wild juvenile loggerhead sea turtles Caretta caretta living offshore Madeira Island, northeast Atlantic. We analyzed the influence of age, sex, sea surface temperature, and body condition index on biochemical parameters including uric acid, total bilirubin, total cholesterol, creatinine kinase (CK), glucose, total protein, urea nitrogen, lactate dehydrogenase, aspartate aminotranspherase (AST), gamma-glutamyl transferase (GGT), albumin, alkaline phosphatase (ALP), sodium (NA), potassium (K), chloride, calcium, phosphorus, and magnesium. Significant positive correlations were found between turtle body size and total cholesterol, total protein, and albumin. Total protein and the enzymes AST and CK were lower than reported levels in adults. Calcium levels were lower than those reported in adult or captive turtles, but similar to wild juveniles from Australian waters, and were interpreted as normal for this age category. These data may be useful to evaluate the health status of stranded or injured animals and to improve veterinary care at rehabilitation centers.

Amelioration of tamoxifen-induced liver injury in rats by grape seed extract, black seed extract and curcumin.

PubMed

El-Beshbishy, Hesham A; Mohamadin, Ahmed M; Nagy, Ayman A; Abdel-Naim, Ashraf B

2010-03-01

Liver injury was induced in female rats using tamoxifen (TAM). Grape seeds (Vitis vinifera) extract (GSE), black seed (Nigella sativa) extract (NSE), curcumin (CUR) or silymarin (SYL) were orally administered to TAM-intoxicated rats. Liver histopathology of TAM-intoxicated:rats showed pathological changes. TAM-intoxication elicited declines in liver antioxidant enzymes levels (glutathione peroxidase, glutathione reductase, superoxide dismutase and catalase), reduced glutathione (GSH) and GSH/GSSG ratio plus the hepatic elevations in lipid peroxides, oxidized glutathione (GSSG), tumor necrosis factor-alpha (TNF-alpha) and serum liver enzymes; alanine transaminase, aspartate transaminase, alkaline phosphatase, lactate dehydrogenase and gamma glutamyl transferase levels. Oral intake of NSE, GSE, CUR or SYL to TAM-intoxicated rats, attenuated histopathological changes and corrected all parameters mentioned above. Improvements were prominent in case of NSE (similarly SYL) > CUR > GSE. Data indicated that NSE, GSE or CUR act as free radicals scavengers and protect TAM-induced liver injury in rats.

The 148 M allele of the PNPLA3 is associated with plasma irisin levels in a population sample of Caucasian children: The PANIC Study.

PubMed

Viitasalo, Anna; Atalay, Mustafa; Pihlajamäki, Jussi; Jääskeläinen, Jarmo; Korkmaz, Ayhan; Kaminska, Dorota; Lindi, Virpi; Lakka, Timo A

2015-07-01

There are no previous data on the association of PNPLA3 I148M polymorphism (rs738409) with circulating adipokines and myokines in children. Subjects were a population sample of 481 Caucasian children aged 6-8 years. We assessed circulating levels of irisin together with IL-6, TNF-α, leptin, high molecular weight (HMW)-adiponectin, alanine aminotransferase (ALT) and gamma-glutamyl transferase (GGT) while the subjects were stratified according to PNPLA3 I148M variants. The PNPLA3 rs738409 polymorphism had a linear relationship with plasma levels of irisin after adjustment for age, sex and body height (p=0.007) but it was not associated with circulating levels of interleukin- 6 (IL-6), tumor-necrosis factor α (TNF-α), leptin or HMW-adiponectin. PNPLA3 148M allele carriers had higher plasma levels of irisin than the non-carriers. This might be due to compensatory mechanism to limit early steatotic and inflammatory changes in the liver. Copyright © 2015 Elsevier Inc. All rights reserved.

Effects of Kombucha on oxidative stress induced nephrotoxicity in rats

PubMed Central

2009-01-01

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

Effects of Kombucha on oxidative stress induced nephrotoxicity in rats.

PubMed

Gharib, Ola Ali

2009-11-27

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

Determining bovine viral diarrhea and infectious bovine rhinotracheitis infections in dairy cattle using precolostral blood.

PubMed

Baillargeon, Paul; Arango-Sabogal, Juan C; Wellemans, Vincent; Fecteau, Gilles

2017-04-01

The objective of this study was to determine if precolostral blood samples are useful to detect apparent fetal infections with bovine viral diarrhea (BVD) and infectious bovine rhinotracheitis (IBR) viruses. A convenience sample of 317 sera from 50 Canadian herds was used in the study. Antibody level was measured using 2 commercial IBR and BVD ELISA kits. Precolostral status of sera was confirmed on 304 samples using serum gamma-glutamyl transferase activity. Postcolostral serum samples yielded a higher proportion of positive results to IBR (OR = 86; 95% CI: 17.8 to 415.7) and BVD (OR = 199.3; 95% CI: 41.7 to 952.3) than did precolostral samples. All positive precolostral serum samples ( n = 7 of 304) originated from calves born to vaccinated cows. Postcolostral positive serum samples ( n = 11 of 13) originated mostly (60%) from calves born to non-vaccinated cows. Precolostral serum sampling can detect apparent fetal infections in a herd.

Associations between dietary fiber and inflammation, hepatic function, and risk of type 2 diabetes in older men: potential mechanisms for the benefits of fiber on diabetes risk.

PubMed

Wannamethee, S Goya; Whincup, Peter H; Thomas, Mary C; Sattar, Naveed

2009-10-01

To examine the relationship between dietary fiber and the risk of type 2 diabetes in older men and the role of hepatic and inflammatory markers. The study was performed prospectively and included 3,428 nondiabetic men (age 60-79 years) followed up for 7 years, during which there were 162 incident cases of type 2 diabetes. Low total dietary fiber (lowest quartile < or =20 g/day) was associated with increased risk of diabetes after adjustment for total calorie intake and potential confounders (relative risk -1.47 [95% CI 1.03-2.11]). This increased risk was seen separately for both low cereal and low vegetable fiber intake. Dietary fiber was inversely associated with inflammatory markers (C-reactive protein, interleukin-6) and with tissue plasminogen activator and gamma-glutamyl transferase. Adjustment for these markers attenuated the increased risk (1.28 [0.88-1.86]). Dietary fiber is associated with reduced diabetes risk, which may be partly explained by inflammatory markers and hepatic fat deposition.

Effect of Peppermint Oil on Serum Lipid Peroxidation and Hepatic Enzymes after Immobility Stress in Mice

PubMed Central

Marjani, Abdoljalal; Rahmati, Reza; Mansourian, Azad Reza; Veghary, Gholamreza

2012-01-01

This study was undertaken to determine the influences of various doses of peppermint oil on the hepatic en-zymes, alanine transaminase, apartate tranaminase, alkaline phosphotase and gamma glutamyl transferase and the level of malondialdehyde in the serum of mice with and without immobility stress. The mice exposed to drink water, 0.9, 27 and 60 mg/kg peppermint oil from the days 1 to 5 for a period of 4 h before and after immobility stress. Serum MDA in-creased in treatment group II, III and IV after immobility stress. There was a significant decrease in ALT in treatment group III and IV after immobility stress. There were also significant decreases in ALP and GGT in treatment group IV af-ter immobility stress. This result may suggest that, MDA level is higher in immobilization stress group than in the un-immobilized animals in serum and this results show that enzyme activities decreased after immobilization stress. PMID:22654997

Primary photosensitization in cattle caused by Froelichia humboldtiana.

PubMed

Souza, Paulo E C; Oliveira, Samuel S; Aguiar-Filho, Cristiano R; Cunha, Ana L B; Albuquerque, Raquel F; Evêncio-Neto, Joaquim; Riet-Correa, Franklin; Mendonça, Fábio S

2012-12-01

Three outbreaks of primary photosensitization caused by Froelichia humboldtiana are reported in the semiarid region of the states of Pernambuco and Paraíba, in northeastern Brazil. The disease occurred from March to June 2011, affecting 27 bovines out of a total of 70. The main lesions consisted of dermatitis of the white skin, with edema and necrosis. All the bovines recovered after removal from the areas invaded by F. humboldtiana. To produce the disease experimentally, one bovine with white skin was placed for 14 days into an area with F. humboldtiana as the sole forage. This bovine presented photodermatitis on the third day of consumption. The serum concentrations of total, indirect, and conjugated bilirubin and the serum activities of gamma-glutamyl transferase (GGT) and aspartate-aminotransferase (AST) in the spontaneously affected cattle and in the experimental cattle remained within normal ranges. It is concluded that F. humboldtiana causes primary photosensitization in cattle in northeastern Brazil. Copyright © 2012 Elsevier Ltd. All rights reserved.

Ablation of Mrds1/Ofcc1 Induces Hyper-γ-Glutamyl Transpeptidasemia without Abnormal Head Development and Schizophrenia-Relevant Behaviors in Mice

PubMed Central

Ohnishi, Tetsuo; Yamada, Kazuo; Watanabe, Akiko; Ohba, Hisako; Sakaguchi, Toru; Honma, Yota; Iwayama, Yoshimi; Toyota, Tomoko; Maekawa, Motoko; Watanabe, Kazutada; Detera-Wadleigh, Sevilla D.; Wakana, Shigeharu; Yoshikawa, Takeo

2011-01-01

Mutations in the Opo gene result in eye malformation in medaka fish. The human ortholog of this gene, MRDS1/OFCC1, is a potentially causal gene for orofacial cleft, as well as a susceptibility gene for schizophrenia, a devastating mental illness. Based on this evidence, we hypothesized that this gene could perform crucial functions in the development of head and brain structures in vertebrates. To test this hypothesis, we created Mrds1/Ofcc1-null mice. Mice were examined thoroughly using an abnormality screening system referred to as “the Japan Mouse Clinic”. No malformations of the head structure, eye or other parts of the body were apparent in these knockout mice. However, the mutant mice showed a marked increase in serum γ-glutamyl transpeptidase (GGT), a marker for liver damage, but no abnormalities in other liver-related measurements. We also performed a family-based association study on the gene in schizophrenia samples of Japanese origin. We found five single nucleotide polymorphisms (SNPs) located across the gene that showed significant transmission distortion, supporting a prior report of association in a Caucasian cohort. However, the knockout mice showed no behavioral phenotypes relevant to schizophrenia. In conclusion, disruption of the Mrds1/Ofcc1 gene elicits asymptomatic hyper-γ-glutamyl-transpeptidasemia in mice. However, there were no phenotypes to support a role for the gene in the development of eye and craniofacial structures in vertebrates. These results prompt further examination of the gene, including its putative contribution to hyper-γ-glutamyl transpeptidasemia and schizophrenia. PMID:22242126

Mitochondrial and cytoplasmic isoleucyl-, glutamyl- and arginyl-tRNA synthetases of yeast are encoded by separate genes.

PubMed

Tzagoloff, A; Shtanko, A

1995-06-01

Three complementation groups of a pet mutant collection have been found to be composed of respiratory-deficient deficient mutants with lesions in mitochondrial protein synthesis. Recombinant plasmids capable of restoring respiration were cloned by transformation of representatives of each complementation group with a yeast genomic library. The plasmids were used to characterize the complementing genes and to institute disruption of the chromosomal copies of each gene in respiratory-proficient yeast. The sequences of the cloned genes indicate that they code for isoleucyl-, arginyl- and glutamyl-tRNA synthetases. The properties of the mutants used to obtain the genes and of strains with the disrupted genes indicate that all three aminoacyl-tRNA synthetases function exclusively in mitochondrial proteins synthesis. The ISM1 gene for mitochondrial isoleucyl-tRNA synthetase has been localized to chromosome XVI next to UME5. The MSR1 gene for the arginyl-tRNA synthetase was previously located on yeast chromosome VIII. The third gene MSE1 for the mitochondrial glutamyl-tRNA synthetase has not been localized. The identification of three new genes coding for mitochondrial-specific aminoacyl-tRNA synthetases indicates that in Saccharomyces cerevisiae at least 11 members of this protein family are encoded by genes distinct from those coding for the homologous cytoplasmic enzymes.

γ-PGA and MTGase improve the formation of ε-(γ-glutamyl) lysine cross-links within hairtail (Trichiurus haumela) surimi protein.

PubMed

Hu, Yaqin; Shao, Ying; Wu, Chunhua; Yuan, Chunhong; Ishimura, Gakushi; Liu, Wenjuan; Chen, Shiguo

2018-03-01

The present study investigated the mechanism of ε-(γ-glutamyl) lysine cross-links within hairtail (Trichiurus haumela) surimi protein via γ-polyglutamic acid (γ-PGA) and MTGase. The results indicated that the addition of MTGase and γ-PGA markedly improved the gelation properties of hairtail surimi protein, including its maximum breaking force and deformation, water holding capacity and gel strength. The maximum improvements were achieved by adding 0.5units MTGase/g meat paste in combination with 0.06% γ-PGA. SDS-PAGE showed that the band intensity of cross-linked proteins increased, whereas that of myosin heavy chain decreased after treatments. Further scanning electron microscopy (SEM) analysis showed the formation of a denser gel matrix, which was caused by much stronger and more inter- and intra-molecular cross-linking of proteins, via MTGase catalysing ε-(γ-glutamyl) lysine cross-links formed between lysine residues in the gel protein and glutamic residues in the hydrolytic γ-PGA. The results provide reliable guidance for the improvement of hairtail surimi protein gelation properties. Copyright © 2017 Elsevier Ltd. All rights reserved.

Changes in white cell estimates and plasma chemistry measurements following oral or external dosing of double-crested cormorants, Phalacocorax auritus, with artificially weathered MC252 oil.

PubMed

Dean, Karen M; Bursian, Steven J; Cacela, Dave; Carney, Michael W; Cunningham, Fred L; Dorr, Brian; Hanson-Dorr, Katie C; Healy, Kate A; Horak, Katherine E; Link, Jane E; Lipton, Ian; McFadden, Andrew K; McKernan, Moira A; Harr, Kendal E

2017-12-01

Scoping studies were designed whereby double-crested cormorants (Phalacocorax auritus) were dosed with artificially weathered Deepwater Horizon (DWH) oil either daily through oil injected feeder fish, or by application of oil directly to feathers every three days. Preening results in oil ingestion, and may be an effective means of orally dosing birds with toxicant to improve our understanding of the full range of physiological effects of oral oil ingestion on birds. Blood samples collected every 5-6 days were analyzed for a number of clinical endpoints including white blood cell (WBC) estimates and differential cell counts. Plasma biochemical evaluations were performed for changes associated with oil toxicity. Oral dosing and application of oil to feathers resulted in clinical signs and statistically significant changes in a number of biochemical endpoints consistent with petroleum exposure. In orally dosed birds there were statistically significant decreases in aspartate amino transferase (AST) and gamma glutamyl transferase (GGT) activities, calcium, chloride, cholesterol, glucose, and total protein concentrations, and increases in plasma urea, uric acid, and phosphorus concentrations. Plasma electrophoresis endpoints (pre-albumin, albumin, alpha-2 globulin, beta globulin, and gamma globulin concentrations and albumin: globulin ratios) were decreased in orally dosed birds. Birds with external oil had increases in urea, creatinine, uric acid, creatine kinase (CK), glutamate dehydrogenase (GLDH), phosphorus, calcium, chloride, potassium, albumin, alpha-1 globulin and alpha-2 globulin. Decreases were observed in AST, beta globulin and glucose. WBC also differed between treatments; however, this was in part driven by monocytosis present in the externally oiled birds prior to oil treatment. Copyright © 2017 Elsevier Inc. All rights reserved.

GLUTATHIONE S-TRANSFERASE-MEDIATED METABOLISM OF BROMODICHLOROMETHANE

EPA Science Inventory

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

Fluorescent techniques for discovery and characterization of phosphopantetheinyl transferase inhibitors

PubMed Central

Kosa, Nicolas M.; Foley, Timothy L.; Burkart, Michael D.

2016-01-01

Phosphopantetheinyl transferase (E.C. 2.7.8.-) activates biosynthetic pathways that synthesize both primary and secondary metabolites in bacteria. Inhibitors of these enzymes have the potential to serve as antibiotic compounds that function through a unique mode of action and possess clinical utility. Here we report a direct and continuous assay for this enzyme class based upon monitoring polarization of a fluorescent phosphopantetheine analog as it is transferred from a low molecular weight coenzyme A substrate to higher molecular weight protein acceptor. We demonstrate the utility of this method for the biochemical characterization of phosphopantetheinyl transferase Sfp, a canonical representative from this class. We also establish the portability of this technique to other homologs by adapting the assay to function with the human phosphopantetheinyl transferase, a target for which a microplate detection method does not currently exist. Comparison of these targets provides a basis to predict therapeutic index of inhibitor candidates and offers a valuable characterization of enzyme activity. PMID:24192555

Influence of thermal processing on hydrolysis and stability of folate poly-gamma-glutamates in broccoli (Brassica oleracea var. italica), carrot (Daucus carota) and tomato (Lycopersicon esculentum).

PubMed

Munyaka, Ann Wambui; Verlinde, Philippe; Mukisa, Ivan Muzira; Oey, Indrawati; Van Loey, Ann; Hendrickx, Marc

2010-04-14

The folate poly-gamma-glutamate profile, their concentrations, and hydrolysis by endogenous gamma-glutamyl hydrolase (GGH) were evaluated in broccoli, carrot and tomato. Further studies on the effect of time and temperature on folate poly-gamma-glutamate hydrolysis and stability were carried out in broccoli since this vegetable showed the highest long-chain and total folate poly-gamma-glutamate concentration. The evolution of l-ascorbic acid, total phenols and Trolox equivalent antioxidant capacity (TEAC) values was evaluated in parallel. Upon thermal inactivation of GGH prior to crushing, it was observed that broccoli, carrot and tomato contained poly-gamma-glutamates with one to seven glutamate residues but differed in the predominant poly-gamma-glutamates. Crushing of raw broccoli, carrot and tomato resulted in significant poly-gamma-glutamate profile changes in broccoli and carrot (indicating GGH-catalyzed hydrolysis) but not in tomato. In this study, the actual crushing of raw broccoli matrix had a greater effect on folate poly-gamma-glutamate hydrolysis than incubation conditions (0-30 min at 25-55 degrees C). During treatments at 25-140 degrees C, folate retention was higher at 80 and 100 degrees C than at the other temperatures. A similar trend in thermal stability was observed for folates, vitamin C, total phenols and TEAC value, an indication that conditions that result in endogenous antioxidants degradation might also result in folate degradation.

Controversial results of therapy with mesenchymal stem cells in the acute phase of canine distemper disease.

PubMed

Pinheiro, A O; Cardoso, M T; Vidane, A S; Casals, J B; Passarelli, D; Alencar, A L F; Sousa, R L M; Fantinato-Neto, P; Oliveira, V C; Lara, V M; Ambrósio, C E

2016-05-23

Distemper disease is an infectious disease reported in several species of domestic and wild carnivores. The high mortality rate of animals infected with canine distemper virus (CDV) treated with currently available therapies has driven the study of new efficacious treatments. Mesenchymal stem cell (MSC)-based therapy is a promising therapeutic option for many degenerative, hereditary, and inflammatory diseases. Therefore, the aim of this study was to characterize stem cells derived from the canine fetal olfactory epithelium and to assess the systemic response of animals infected with CDV to symptomatic therapy and treatment with MSCs. Eight domestic mongrel dogs (N = 8) were divided into two groups: support group (SG) (N = 5) and support group + cell therapy (SGCT) (N = 3), which were monitored over 15 days. Blood samples were collected on days 0, 6, 9, 12, and 15 to assess blood count and serum biochemistry (urea, creatinine, alanine transferase, alkaline phosphatase, gamma-glutamyl transferase, total protein, albumin, and globulin), and urine samples were obtained on days 0 and 15 for urinary evaluation (urine I). The results showed a high mortality rate (SG = 4 and SGCT = 2), providing inadequate data on the clinical course of CDV infection. MSC therapy resulted in no significant improvement when administered during the acute phase of canine distemper disease, and a prevalence of animals with high mortality rate was found in both groups due to the severity of symptoms.

Iron loading, alcohol and mortality: A prospective study.

PubMed

Schutte, Rudolph; Huisman, Hugo; Mels, Catharina M C; Botha, Shani; Kruger, Ruan; Smith, Wayne; Kruger, Iolanthé M; Hawkins, Michelle; Smith, Lee; Breet, Yolandi; Schutte, Aletta E

2018-05-16

The relationship between total body iron and cardiovascular disease remains controversial and information absent in black sub-Saharan Africans in whom alcohol consumption tends to be high. The level of total body iron is tightly regulated, however this regulation is compromised by high alcohol intake causing iron loading. The aim of this study is to investigate total body iron, as represented by serum ferritin, and its interaction with measures of alcohol intake in predicting all-cause and cardiovascular mortality. We followed health outcomes for a median of 9.22 years in 877 randomly selected HIV negative African women (mean age: 50.4 years). One hundred and five deaths occurred of which 40 were cardiovascular related. Ferritin averaged 84.0 (5th to 95th percentile interval, 7.5-533.3) ng/ml and due to the augmenting effect of inflammation, lowered to 75.3 (6.9-523.2) ng/ml after excluding 271 participants with high-sensitivity C-reactive protein (CRP) levels (above 8 mg/l). CRP increased by quartiles of ferritin in the total group (P trend = 0.002), but this relationship was absent after excluding the 271 participants with high CRP values (P trend = 0.10). Ferritin, gamma-glutamyl transferase and carbohydrate deficient transferrin (all P < 0.0001) were higher in drinkers compared to non-drinkers, but CRP was similar (P = 0.77). In multivariable-adjusted analyses, ferritin predicted both all-cause (hazard ratio, 2.08; 95% confidence interval, 1.62-2.68; P < 0.0001) and cardiovascular (1.94; 1.29-2.92; P = 0.002) mortality. In participants with CRP levels below or equal to 8 mg/l, the significant relationship remained between ferritin and all-cause (2.51; 1.81-3.49; P < 0.0001) and cardiovascular mortality (2.34; 1.45-3.76; P = 0.0005). In fully adjusted models, interactions existed between ferritin and gamma-glutamyl transferase, self-reported alcohol use and carbohydrate deficient transferrin in predicting all-cause (P ≤ 0.012) and

Cloning and expression of γ-glutamyl transpeptidase and its relationship to greening in crushed garlic (Allium sativum) cloves.

PubMed

Cho, Jungeun; Park, Minkyu; Choi, Doil; Lee, Seung Koo

2012-01-30

Garlic greening occurs when garlic cloves are stored at low temperature, increasing 1-propenyl cysteine sulfoxide, which is induced by γ-glutamyl transpeptidase (GGT) activity. Although the metabolism of the γ-glutamyl peptide is important for the biosynthesis of green pigments in crushed garlic cloves, garlic GGT is poorly characterised. For the analysis of GGT at the gene level, the garlic GGT sequence was partially cloned using an onion GGT sequence. The relationship between garlic greening and related gene expressions, depending on storage condition, was investigated using reverse transcription polymerase chain reaction for garlic GGT and alliinase. Three storage conditions were set: A, storage at a constant temperature of 20 °C; B, storage at 20 °C for 3 months and then transfer to 0 °C for an additional 3 months; C, storage at 0 °C for 3 months and then transfer to 20 °C for an additional 3 months. GGT expression increased under storage condition B and decreased under storage condition C. However, alliinase expression was not affected by storage condition. Greening in crushed garlic cloves increases with increasing GGT expression at low temperature, while alliinase expression is not affected. Copyright © 2011 Society of Chemical Industry.

Molecular Cloning of Adenosinediphosphoribosyl Transferase.

DTIC Science & Technology

1987-09-08

nature of the blocking group is unknown, except its identity with pyroglutamic acid was ruled out by its insensitivity to pyroglutaminase (not shown...AdenosinediphosphoribOSyl Transferase (ADPRT) is: 1) the complete amino acid sequence of this large protein is best determined -from the DNA !equence of the gene, 2...enzyme (I), determination of its peptide structure (II) and application of synthetic DNA probes (III) derived from amino acid sequences, resulting in the

Role of Glutathione S-Transferase Pi in Cisplatin Induced Nephrotoxicity

PubMed Central

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

2009-01-01

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

Low-dose radiation modifies skin response to acute gamma-rays and protons.

PubMed

Mao, Xiao Wen; Pecaut, Michael J; Cao, Jeffrey D; Moldovan, Maria; Gridley, Daila S

2013-01-01

The goal of the present study was to obtain pilot data on the effects of protracted low-dose/low-dose-rate (LDR) γ-rays on the skin, both with and without acute gamma or proton irradiation (IR). Six groups of C57BL/6 mice were examined: a) 0 Gy control, b) LDR, c) Gamma, d) LDR+Gamma, e) Proton, and f) LDR+Proton. LDR radiation was delivered to a total dose of 0.01 Gy (0.03 cGy/h), whereas the Gamma and Proton groups received 2 Gy (0.9 Gy/min and 1.0 Gy/min, respectively). Assays were performed 56 days after exposure. Skin samples from all irradiated groups had activated caspase-3, indicative of apoptosis. The significant (p<0.05) increases in immunoreactivity in the Gamma and Proton groups were not present when LDR pre-exposure was included. However, the terminal deoxynucleotidyl transferase dUTP nick-end labeling assay for DNA fragmentation and histological examination of hematoxylin and eosin-stained sections revealed no significant differences among groups, regardless of radiation regimen. The data demonstrate that caspase-3 activation initially triggered by both forms of acute radiation was greatly elevated in the skin nearly two months after whole-body exposure. In addition, LDR γ-ray priming ameliorated this response.

Infection-specific phosphorylation of glutamyl-prolyl tRNA synthetase induces antiviral immunity

PubMed Central

Lee, Eun-Young; Lee, Hyun-Cheol; Kim, Hyun-Kwan; Jang, Song Yee; Park, Seong-Jun; Kim, Yong-Hoon; Kim, Jong Hwan; Hwang, Jungwon; Kim, Jae-Hoon; Kim, Tae-Hwan; Arif, Abul; Kim, Seon-Young; Choi, Young-Ki; Lee, Cheolju; Lee, Chul-Ho; Jung, Jae U; Fox, Paul L; Kim, Sunghoon; Lee, Jong-Soo; Kim, Myung Hee

2016-01-01

The mammalian cytoplasmic multi-tRNA synthetase complex (MSC) is a depot system that regulates non-translational cellular functions. Here we found that the MSC component glutamyl-prolyl-tRNA synthetase (EPRS) switched its function following viral infection and exhibited potent antiviral activity. Infection-specific phosphorylation of EPRS at Ser990 induced its dissociation from the MSC, after which it was guided to the antiviral signaling pathway, where it interacted with PCBP2, a negative regulator of mitochondrial antiviral signaling protein (MAVS) that is critical for antiviral immunity. This interaction blocked PCBP2-mediated ubiquitination of MAVS and ultimately suppressed viral replication. EPRS-haploid (Eprs+/−) mice showed enhanced viremia and inflammation and delayed viral clearance. This stimulus-inducible activation of MAVS by EPRS suggests an unexpected role for the MSC as a regulator of immune responses to viral infection. PMID:27595231

The Hepatoprotective Effect of Vitamin A against Gasoline Vapor Toxicity in Rats

PubMed Central

Uboh, Friday E.; Ekaidem, Itemobong S.; Ebong, Patrick E.; Umoh, Ime B.

2009-01-01

Background Changes in the activities of plasma alanine amino transferase (ALT), aspartate amino transferase (AST), gamma glutamyl transferase (GGT), and alkaline phosphatase (ALP) are used to assess the functional state of the liver. Significant increase in the activities of these enzymes commonly indicates the hepatotoxicity of chemical agent(s) in the body. Exposure of male and female rats to 17.8 cm3h-1m-3 of Premium Motor Spirit (PMS) blend unleaded gasoline (UG) vapors for 6 hr/day, 5 days/week for 20 weeks have been observed to cause hepatotoxicity. In this study, the potential hepatoprotective effect of vitamin A (retinol) against gasoline vapours-induced toxicity was investigated in male and female rats. Methods Retinol (400 IU/kg/day) was orally administered to the test rats concomitant with the gasoline vapor exposure in the last two weeks of the experiment. Results The results obtained from this study showed that exposure to gasoline vapors caused significant increase (P < 0.05) in the activities of serum ALT, AST, ALP, GGT and bilirubin in both male and female rats. The treatment of the male and female test rats with vitamin A produced a significant decrease (P < 0.05) in the activities of these parameters, compared with the test rats without treatment; but insignificant increase(P ≥ 0.05), compared with the control. Conclusions The result of this study demonstrates the beneficial effects of retinol, at prophylactic dosage, against gasoline vapours hepatotoxicity in male and female rats, thereby suggesting that retinol may be used to prevent hepatotoxicity in individuals frequently exposed to gasoline vapours. PMID:27933127

Biosynthesis of 2-Hydroxyacid-Containing Polyhydroxyalkanoates by Employing butyryl-CoA Transferases in Metabolically Engineered Escherichia coli.

PubMed

David, Yokimiko; Joo, Jeong Chan; Yang, Jung Eun; Oh, Young Hoon; Lee, Sang Yup; Park, Si Jae

2017-11-01

The authors previously reported the production of polyhydroxyalkanoates (PHAs) containing 2-hydroxyacid monomers by expressing evolved Pseudomonas sp. 6-19 PHA synthase and Clostridium propionicum propionyl-CoA transferase in engineered microorganisms. Here, the authors examined four butyryl-CoA transferases from Roseburia sp., Eubacterium hallii, Faecalibacterium prausnitzii, and Anaerostipes caccae as potential CoA-transferases to support synthesis of polymers having 2HA monomer. In vitro activity analyses of the four butyryl-CoA transferases suggested that each butyryl-CoA transferase has different activities towards 2-hydroxybutyrate (2HB), 3-hydroxybutyrate (3HB), and lactate (LA). When Escherichia coli XL1-Blue expressing Pseudomonas sp. 6-19 PhaC1437 along with one butyryl-CoA transferase is cultured in chemically defined MR medium containing 20 g L -1 of glucose, 2 g L -1 of sodium 3-hydroxybutyrate, and various concentrations of sodium 2-hydroxybutyrate, PHAs consisting of 3HB, 2HB, and LA are produced. The monomer composition of PHAs agreed well with the substrate specificities of butyryl-CoA transferases from E. hallii, F. prausnitzii, and A. caccae, but not Roseburia sp. When E. coli XL1-Blue expressing PhaC1437 and E. hallii butyryl-CoA transferase is cultured in MR medium containing 20 g L -1 of glucose and 2 g L -1 of sodium 2-hydroxybutyrate, P(65.7 mol% 2HB-co-34.3 mol% LA) is produced with the highest PHA content of 30 wt%. Butyryl-CoA transferases also supported the production of P(3HB-co-2HB-co-LA) from glucose as the sole carbon source in E. coli XL1-Blue strains when one of these bct genes is expressed with phaC1437, cimA3.7, leuBCD, panE, and phaAB genes. Butyryl-CoA transferases characterized in this study can be used for engineering of microorganisms that produce PHAs containing novel 2-hydroxyacid monomers. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Hyperproduction of γ-glutamyl transpeptidase from Bacillus licheniformis ER15 in the presence of high salt concentration.

PubMed

Bindal, Shruti; Gupta, Rani

2017-02-07

Microbial γ-glutamyl transpeptidases (GGTs) have been exploited in biotechnological, pharmaceutical, and food sectors for the synthesis of various γ-glutamyl compounds. But, till date, no bacterial GGTs are commercially available in the market because of lower levels of production from various sources. In the current study, production of GGT from Bacillus licheniformis ER15 was investigated to achieve high GGT titers. Hyperproduction of GGT from B. licheniformis ER15 was achieved with 6.4-fold enhancement (7921.2 ± 198.7 U/L) by optimization of culture medium following one-variable-at-a-time strategy and statistical approaches. Medium consisting of Na 2 HPO 4 : 0.32% (w/v); KH 2 PO 4 : 0.15% (w/v); starch: 0.1% (w/v); soybean meal: 0.5% (w/v); NaCl: 4.0% (w/v), and MgCl 2 : 5 mM was found to be optimal for maximum GGT titers. Maximum GGT titers were obtained, in the optimized medium at 37°C and 200 rpm, after 40 h. It was noteworthy that GGT production was a linear function of sodium chloride concentration, as observed during response surface methodology. While investigating the role of NaCl on GGT production, it was found that NaCl drastically decreased subtilisin concentration and indirectly increasing GGT recovery. B. licheniformis ER15 is proved to be a potential candidate for large-scale production of GGT enzyme and its commercialization.

Altered glutamyl-aminopeptidase activity and expression in renal neoplasms

PubMed Central

2014-01-01

Background Advances in the knowledge of renal neoplasms have demonstrated the implication of several proteases in their genesis, growth and dissemination. Glutamyl-aminopeptidase (GAP) (EC. 3.4.11.7) is a zinc metallopeptidase with angiotensinase activity highly expressed in kidney tissues and its expression and activity have been associated wtih tumour development. Methods In this prospective study, GAP spectrofluorometric activity and immunohistochemical expression were analysed in clear-cell (CCRCC), papillary (PRCC) and chromophobe (ChRCC) renal cell carcinomas, and in renal oncocytoma (RO). Data obtained in tumour tissue were compared with those from the surrounding uninvolved kidney tissue. In CCRCC, classic pathological parameters such as grade, stage and tumour size were stratified following GAP data and analyzed for 5-year survival. Results GAP activity in both the membrane-bound and soluble fractions was sharply decreased and its immunohistochemical expression showed mild staining in the four histological types of renal tumours. Soluble and membrane-bound GAP activities correlated with tumour grade and size in CCRCCs. Conclusions This study suggests a role for GAP in the neoplastic development of renal tumours and provides additional data for considering the activity and expression of this enzyme of interest in the diagnosis and prognosis of renal neoplasms. PMID:24885240

The Gamma-Glutamyl-Transpeptidase to Platelet Ratio Does not Show Advantages than APRI and Fib-4 in Diagnosing Significant Fibrosis and Cirrhosis in Patients With Chronic Hepatitis B: A Retrospective Cohort Study in China.

PubMed

Li, Qiang; Song, Jie; Huang, Yuxian; Li, Xinyan; Zhuo, Qibin; Li, Weixia; Chen, Chong; Lu, Chuan; Qi, Xun; Chen, Liang

2016-04-01

The gamma-glutamyl-transpeptidase to platelet ratio (GPR) is a new liver fibrosis model, which is reported to be more accurate than aspartate transaminase (AST) to platelet ratio index (APRI) and fibrosis index based on the four factors (Fib-4) for diagnosing significant fibrosis and cirrhosis in patients with chronic hepatitis B (CHB) in West Africa. The aim of this study is to assess the diagnostic accuracy of GPR for significant fibrosis and cirrhosis in Chinese CHB patients, and explore whether GPR deserves to be popularized in China. A total of 372 CHB patients who underwent liver biopsies and routine laboratory tests were retrospectively studied. The Scheuer scoring system was adopted as the pathological standard of liver fibrosis. Using liver histology as a gold standard, the diagnostic accuracies of GPR, APRI, and Fib-4 for significant fibrosis and cirrhosis are evaluated and compared by the receiver operating characteristic (ROC) curves and the area under the ROC curves (AUROCs). Of these 372 patients, 176 (47.3%), 129 (34.7%), and 72 (19.4%) were classified as having significant fibrosis (≥ S2), severe fibrosis (≥ S3), and cirrhosis (S4), respectively. The AUROCs of GPR for significant fibrosis (0.72 vs. 0.78; P = 0.01), severe fibrosis (0.75 vs. 0.80; P = 0.04), and cirrhosis (0.78 vs. 0.83; P = 0.02) were lower than those of APRI. The AUROCs of GPR and Fib-4 for diagnosing significant fibrosis (0.72 vs. 0.70; P = 0.29), severe fibrosis (0.75 vs. 0.73; P = 0.33), and cirrhosis (0.78 vs. 0.75; P = 0.38) were comparable. GPR is a new serum diagnostic model for liver fibrosis and cirrhosis, but does not show advantages than APRI and Fib-4 in identifying significant fibrosis, severe fibrosis, and cirrhosis in CHB patients in China.

Elongation of the Poly-γ-glutamate Tail of F420 Requires Both Domains of the F420:γ-Glutamyl Ligase (FbiB) of Mycobacterium tuberculosis*

PubMed Central

Bashiri, Ghader; Rehan, Aisyah M.; Sreebhavan, Sreevalsan; Baker, Heather M.; Baker, Edward N.; Squire, Christopher J.

2016-01-01

Cofactor F420 is an electron carrier with a major role in the oxidoreductive reactions of Mycobacterium tuberculosis, the causative agent of tuberculosis. A γ-glutamyl ligase catalyzes the final steps of the F420 biosynthesis pathway by successive additions of l-glutamate residues to F420-0, producing a poly-γ-glutamate tail. The enzyme responsible for this reaction in archaea (CofE) comprises a single domain and produces F420-2 as the major species. The homologous M. tuberculosis enzyme, FbiB, is a two-domain protein and produces F420 with predominantly 5–7 l-glutamate residues in the poly-γ-glutamate tail. The N-terminal domain of FbiB is homologous to CofE with an annotated γ-glutamyl ligase activity, whereas the C-terminal domain has sequence similarity to an FMN-dependent family of nitroreductase enzymes. Here we demonstrate that full-length FbiB adds multiple l-glutamate residues to F420-0 in vitro to produce F420-5 after 24 h; communication between the two domains is critical for full γ-glutamyl ligase activity. We also present crystal structures of the C-terminal domain of FbiB in apo-, F420-0-, and FMN-bound states, displaying distinct sites for F420-0 and FMN ligands that partially overlap. Finally, we discuss the features of a full-length structural model produced by small angle x-ray scattering and its implications for the role of N- and C-terminal domains in catalysis. PMID:26861878

[Nodular regenerative hyperplasia associated with common variable immunodeficiency and other comorbidities].

PubMed

León, Rafael; Sánchez-Martínez, Rosario; Palazón, José M; Payá, Artemio; Ramos, José M; Pinargote, Héctor

2016-03-18

Currently, there are not many data on the evolution of nodular regenerative hyperplasia (NRH) associated or not with underlying diseases and in particular that associated with common variable inmunodeficiency (CVID). Twenty cases of NRH are presented, and the differences between the cases associated with CVID and those related to other diseases are analysed. Retrospective and descriptive study over a period of 14 years. Twelve out of the 20 patients were men; the median age was 51 years. CVID was the main illness associated with NRH. In patients with CVID and NRH, gastrointestinal haemorrhage was more common, all the patients had high gamma glutamyl transferase and alkaline phosphatase and none had altered albumin and bilirubin levels compared to the patients without CVID. On follow-up, 50% of patients with CVID (2/4) had died compared to 33.3% (5/15) without CVID. NRH in patients with CVID seems to have more biochemical data of anicteric cholestasis and portal hypertension and could be associated with lower survival. Copyright © 2015 Elsevier España, S.L.U. All rights reserved.

Lipemia interferences in routine clinical biochemical tests.

PubMed

Calmarza, Pilar; Cordero, José

2011-01-01

Lipemic specimens are a common and frequent, but yet unresolved problem in clinical chemistry, and may produce significant interferences in the analytical results of different biochemical parameters. The aim of this study was to examine the effect of lipid removal using ultracentrifugation of lipemic samples, on some routine biochemistry parameters. Among all the samples obtained daily in our laboratory, the ones which were visibly muddy were selected and underwent to a process of ultracentrifugation, being determined a variety of biochemical tests before and after ultracentrifugation. A total of 110 samples were studied. We found significant differences in all the parameters studied except for total bilirubin, glucose, gamma-glutamyl transferase (GGT) and aspartate aminotransferase (AST). The greatest differences in the parameters analyzed were found in the concentration of alanine aminotransferase (ALT) (7.36%) and the smallest ones in the concentration of glucose (0.014%). Clinically significant interferences were found for phosphorus, creatinine, total protein and calcium. Lipemia causes clinically significant interferences for phosphorus, creatinine, total protein and calcium measurement and those interferences could be effectively removed by ultracentrifugation.

Golden berry juice attenuates the severity of hepatorenal injury.

PubMed

El-Gengaihi, Souad E; Hamed, Manal A; Khalaf-Allah, Abd El-Rahman M; Mohammed, Mona A

2013-12-01

The aim of the present work is to investigate the potential of Physalis peruviana fruits as a hepatorenal protective agent against carbon tetrachloride (CCl4)-induced hepatic and renal fibrosis. The phytochemical screening test revealed the presence of alkaloids, free withanolides, glycowithanolides, and flavonoids. Acute toxicity study (500, 1000, and 1500 mg/kg body weight) revealed extract safety. The biological evaluation was conducted on different animal groups: control, control treated with fruit, CCl4 group, CCl4 treated with fruit, and CCl4 treated with silymarin drug. The evaluation was done through measuring oxidative stress markers: malondialdehyde (MDA), superoxide dismutase (SOD), and nitric oxide (NO). Liver function indices such as aspartate and alanine aminotransferases (AST & ALT), alkaline phosphatase (ALP), gamma glutamyl transferase (GGT), bilirubin, and total protein were estimated. Kidney disorder biomarkers such as creatinine, urea, and serum protein were also evaluated. Treatment improved all the investigated parameters, and the histopathological analysis confirmed our results. In conclusion, Physalis peruviana fruit succeeded to protect liver and kidney against fibrosis. Further studies are needed to identify the molecules responsible for its pharmacological application.

Curcuma longa Linn. extract and curcumin protect CYP 2E1 enzymatic activity against mercuric chloride-induced hepatotoxicity and oxidative stress: A protective approach.

PubMed

Joshi, Deepmala; Mittal, Deepak Kumar; Shukla, Sangeeta; Srivastav, Sunil Kumar; Dixit, Vaibhav A

2017-07-05

The present investigation has been conducted to evaluate the therapeutic potential of Curcuma longa (200mgkg -1 , po) and curcumin (80mgkg -1 , po) for their hepatoprotective efficacy against mercuric chloride (HgCl 2 : 12μmolkg -1 , ip; once only) hepatotoxicity. The HgCl 2 administration altered various biochemical parameters, including transaminases, alkaline phosphatase, lactate dehydrogenase, bilirubin, gamma-glutamyl transferase, triglycerides and cholesterol contents with a concomitant decline in protein and albumin concentration in serum which were restored towards control by therapy of Curcuma longa or curcumin. On the other hand, both treatments showed a protective effect on drug metabolizing enzymes viz. aniline hydroxylase (AH) and amidopyrine-N-demethylase (AND), hexobarbitone induced sleep time and BSP retention. Choleretic, 1,1-diphenyl-2-picryl-hydrazil (DPPH)-free radical scavenging activities and histological studies also supported the biochemical findings. The present study concludes that Curcuma longa extract or curcumin has the ability to alleviate the hepatotoxic effects caused by HgCl 2 in rats. Copyright © 2017 Elsevier GmbH. All rights reserved.

Influence of olive and rosemary leaves extracts on chemically induced liver cirrhosis in male rats

PubMed Central

Al-Attar, Atef M.; Shawush, Nessreen A.

2014-01-01

The current study was undertaken to evaluate the protective activity of olive and rosemary leaves extracts on experimental liver cirrhosis induced by thioacetamide (TAA) in Wistar male rats. Highly significant decline in the values of body weight gain and highly statistically increase of liver/body weight ratio were noted in rats treated with TAA. Furthermore, the levels of serum alanine aminotransferase, aspartate aminotransferase, gamma glutamyl transferase, alkaline phosphatase and total bilirubin were statistically increased. Additionally, light microscopic examination of liver sections from rats treated with TAA showed a marked increase in the extracellular matrix collagen content and bridging fibrosis was prominent. There were bundles of collagen surrounding the lobules that resulted in large fibrous septa and distorted tissue architecture. Interestingly, the findings of this experimental study indicated that the extracts of olive and rosemary leaves and their combination possess hepatoprotective properties against TAA-induced hepatic cirrhosis by inhibiting the physiological and histopathological alterations. Moreover, these results suggest that the hepatoprotective effects of these extracts may be attributed to their antioxidant activities. PMID:25737646

Cloning and expression of clostridium acetobutylicum ATCC 824 acetoacetyl-coenzyme A:acetate/butyrate:coenzyme A-transferase in Escherichia coli

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

Cary, J.W.; Petersen, D.J.; Bennett, G.N.

1990-06-01

Coenzyme A (CoA)-transferase (acetoacetyl-CoA:acetate/butyrate:CoA-transferase (butyrate-acetoacetate CoA-transferase) (EC 2.8.3.9)) of Clostridium acetobutylicum ATCC 824 is an important enzyme in the metabolic shift between the acid-producing and solvent-forming states of this organism. The genes encoding the two subunits of this enzyme have been cloned and subsequent subcloning experiments established the position of the structural genes for CoA-transferase. Complementation of Escherichia coli ato mutants with the recombinant plasmid pCoAT4 (pUC19 carrying a 1.8-kilobase insert of C. acetobutylicum DNA encoding CoA-transferase activity) enabled the transformants to grow on butyrate as a sole carbon source. Despite the ability of CoA-transferase to complement the ato defectmore » in E. coli mutants, Southern blot and Western blot (immunoblot) analyses showed showed that neither the C. acetobutylicum genes encoding CoA-transferase nor the enzyme itself shared any apparent homology with its E. coli counterpart. Polypeptides of M{sub r} of the purified CoA-transferase subunits were observed by Western blot and maxicell analysis of whole-cell extracts of E.coli harboring pCoAT4. The proximity and orientation of the genes suggest that the genes encoding the two subunits of CoA-transferase may form an operon similar to that found in E. coli. In the plasmid, however, transcription appears to be primarily from the lac promoter of the vector.« less

Regulation of a glutamyl-tRNA synthetase by the heme status

PubMed Central

Levicán, Gloria; Katz, Assaf; de Armas, Merly; Núñez, Harold; Orellana, Omar

2007-01-01

Glutamyl-tRNA (Glu-tRNA), formed by Glu-tRNA synthetase (GluRS), is a substrate for protein biosynthesis and tetrapyrrole formation by the C5 pathway. In this route Glu-tRNA is transformed to δ-aminolevulinic acid, the universal precursor of tetrapyrroles (e.g., heme and chlorophyll) by the action of Glu-tRNA reductase (GluTR) and glutamate semialdehyde aminotransferase. GluTR is a target of feedback regulation by heme. In Acidithiobacillus ferrooxidans, an acidophilic bacterium that expresses two GluRSs (GluRS1 and GluRS2) with different tRNA specificity, the intracellular heme level varies depending on growth conditions. Under high heme requirement for respiration increased levels of GluRS and GluTR are observed. Strikingly, when intracellular heme is in excess, the cells respond by a dramatic decrease of GluRS activity and the level of GluTR. The recombinant GluRS1 enzyme is inhibited in vitro by hemin, but NADPH restores its activity. These results suggest that GluRS plays a major role in regulating the cellular level of heme. PMID:17360620

Short communication: Partial replacement of ground corn with algae meal in a dairy cow diet: Milk yield and composition, nutrient digestibility, and metabolic profile.

PubMed

da Silva, G G; Ferreira de Jesus, E; Takiya, C S; Del Valle, T A; da Silva, T H; Vendramini, T H A; Yu, Esther J; Rennó, F P

2016-11-01

This study was undertaken to evaluate the effects of partially replacing dietary ground corn with a microalgae meal from Prototheca moriformis (composed of deoiled microalgae and soyhulls) on milk yield and composition, nutrient intake, total-tract apparent digestibility, and blood profile of lactating dairy cows. Twenty multiparous Holstein cows (57.7±49.4d in milk, 25.3±5.3 of milk yield, and 590±71kg of live weight at the start of experiment, mean ± standard deviation) were used in a cross-over design experiment, with 21-d periods. Diets were no microalgae meal (CON) or 91.8g/kg of microalgae meal partially replacing dietary ground corn (ALG). Cows showed similar milk yield and composition. The 3.5% fat-corrected milk production was 30.2±1.34kg/d for CON and 31.1±1.42kg/d for ALG. Despite cows having similar dry matter intake, ALG increased neutral detergent fiber and ether extract intake. In addition, cows fed ALG exhibited higher ether extract digestibility. No differences were detected in glucose, urea, amino-aspartate transferase, and gamma-glutamyl transferase blood concentrations. Feeding ALG increased the total cholesterol and high-density lipoprotein in blood compared with CON. The microalgae meal may partially replace ground corn in diets of lactating cows without impairing the animal's performance. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Liquid chromatography-mass spectrometry (LC-MS): a powerful combination for selenium speciation in garlic (Allium sativum).

PubMed

Dumont, Emmie; Ogra, Yasumitsu; Vanhaecke, Frank; Suzuki, Kazuo T; Cornelis, Rita

2006-03-01

Liquid chromatography (LC) hyphenated with both elemental and molecular mass spectrometry has been used for Se speciation in Se-enriched garlic. Different species were separated by ion-pair liquid chromatography-inductively coupled plasma mass spectrometry (LC-ICP-MS) after hot-water extraction. They were identified by on-line reversed-phase liquid chromatography-electrospray ionization tandem mass spectrometry (RPLC-ESI-MS-MS). Se-methionine and Se-methylselenocysteine were determined by monitoring their product ions. Another compound, gamma-glutamyl-Se-methylselenocysteine, shown to be the most abundant form of Se in the garlic, was determined without any additional sample pre-treatment after extraction and without the need for a synthesized standard. Product ions for this dipeptide were detected by LC-ESI-MS-MS for three isotopes of Se-78 Se, 80Se: and 82Se. The method was extended to the species extracted during in-vitro gastrointestinal digestion. Because both Se-methylselenocysteine and gamma-glutamyl-Se-methylselenocysteine have anticarcinogenic properties, their extractability and stability during human digestion are very important. Garlic was also treated with saliva, to enable detection and analysis of species extracted during mastication. Detailed information on the extractability of selenium species by both simulated gastric and intestinal fluid are given, and variation of the distribution of Se among the different species with time is discussed. Although the main species in garlic is the dipeptide gamma-glutamyl-Se-methylselenocysteine, Se-methylselenocysteine is the main compound present in the extracts after treatment with gastrointestinal fluids. Two more, so far unknown compounds were observed in the chromatogram. The extracted species and their transformations were analysed by combining LC-ICP-MS and LC-ESI-MS-MS. In both the simulated gastric and intestinal digests, Se-methionine, Se-methylselenocysteine, and gamma-glutamyl

Antihepatotoxic activity of Rosmarinus tomentosus in a model of acute hepatic damage induced by thioacetamide.

PubMed

Galisteo, M; Suárez, A; del Pilar Montilla, M; del Pilar Utrilla, M; Jiménez, J; Gil, A; Faus, M J; Navarro, M

2000-11-01

R. tomentosus is a vegetal species closely related to the culinary rosemary (R. officinalis), a plant reported to contain antihepatotoxic agents. A dried ethanol extract of the aerial parts of Rosmarinus tomentosus (Lamiaceae) and its major fraction separated by column chromatography (fraction F19) were evaluated for antihepatotoxic activity in rats with acute liver damage induced by a single oral dose of thioacetamide. Silymarin was used as a reference antihepatotoxic substance. Pre-treatment with R. tomentosus ethanol extract, fraction F19 or silymarin significantly reduced the impact of thioacetamide toxicity on plasma protein and urea levels as well as on plasma aspartate aminotransferase, alanine aminotransferase, lactate dehydrogenase and gamma-glutamyl transpeptidase activities compared with thioacetamide-treated animals (group T). Pre-treatment with R. tomentosus ethanol extract significantly reduced the impact of thioacetamide damage on alkaline phosphatase and gamma-glutamyl transpeptidase activities compared with group T. Silymarin administration significantly reduced alkaline phosphatase and gamma-glutamyl transpeptidase activities compared with group T. Fraction F19 administration reduced only alkaline phosphatase activity compared with group T. According to these data, R. tomentosus extract shows promising antihepatotoxic activity, suggesting the need to isolate the chemical principles responsible for this activity and to study this activity in a model of thioacetamide-induced cirrhosis. Copyright 2000 John Wiley & Sons, Ltd.

Localization and characterization of γ-glutamyl cyclotransferase in cancer cells.

PubMed

Azumi, Kaoru; Ikeda, Youhei; Takeuchi, Tomoharu; Nomura, Tsuyoshi; Sabau, Sorin V; Hamada, Jun-Ichi; Okada, Futoshi; Hosokawa, Masuo; Yokosawa, Hideyoshi

2009-01-01

Using differential display analysis, we have identified a novel rat gene whose expression is increased during tumor progression in rat mammary carcinoma cell lines. This gene is an ortholog of the human chromosome 7 open reading frame 24 gene (C7orf24) and encodes a protein of 188 amino acids with no recognized protein domains. C7orf24 has been identified as γ-glutamyl cyclotransferase (GGCT), an important enzyme functioning in glutathione homeostasis. Our Northern and Western blot analyses revealed that the GGCT gene is expressed in various normal human and tumor tissues, as well as in cancer cell lines. Among the tumor tissues tested, lung tumor tissue expressed GGCT mRNA more strongly than normal lung tissue. The GGCT protein was found to be localized in the cytoplasmic region of cultured cells, where it forms a homodimer. Analysis of various deletion mutants of the GGCT protein revealed that the region containing amino acid residues 61-120 of the protein is required for its cytoplasmic localization. The comparison of the soft agar colony formation of HBL-100 cells stably expressing GGCT with that of control HBL-100 cells revealed that GGCT does not promote colony formation, suggesting that the role it plays in lung cancer cells is not related to tumorigenesis.

Associated liver enzymes with hyperlipidemic profile in type 2 diabetes patients.

PubMed

Al-Jameil, Noura; Khan, Farah A; Arjumand, Sadia; Khan, Mohammad F; Tabassum, Hajera

2014-01-01

Type 2 diabetes mellitus (T2DM) is characterized by hyperglycemia and is associated with dyslipidemia and disturbed liver function. Aim of the present work is to assess the liver enzymes and to find its association with hyperlipidemic profile in T2DM. Total of 157 subjects were studied and divided into two groups; diabetes (n=81) and non-diabetes (n=76). Various biochemical parameters like fasting glucose, post prandial glucose, HbA1c, total cholesterol (TC), triglycerides (Tg), high density lipoprotein cholesterol (HDL-C), alanine amino transferase (ALT), aspartate amino transferase (AST) and gamma-glutamyl transferase (GGT) were analyzed by ROCHE module Cobas 6000 (C501 & C601) analyzer, kits were procured by ROCHE diagnostics. Low density lipoprotein cholesterol (LDL-C) was estimated by Freidwald's formula. Statistical analysis was performed by applying student t test and Pearson's correlation coefficient, at 0.0001 and 0.05 level of significance, respectively. All the glycemic control parameters, lipid profile parameters except HDL-C and liver enzymes were found increased in diabetes group and significantly differ from non-diabetes group (p>0.0001). ALT showed significant positive correlation with fasting glucose, post prandial glucose, HbA1c, TC, Tg, LDL-C and GGT at p>0.05. AST showed very weak relation with all parameters while GGT was positively associated with fasting glucose, post prandial glucose, HbA1c, TC, Tg, LDL-C and ALT at p>0.05. In conclusion, T2DM incline to elevate liver enzymes, especially ALT and GGT were of significance. Routine screening of ALT and GGT in T2DM patients may assists early detection of liver abnormalities and to arrest the progress of disease.

Reaction of rat liver glutathione S-transferases and bacterial dichloromethane dehalogenase with dihalomethanes.

PubMed

Blocki, F A; Logan, M S; Baoli, C; Wackett, L P

1994-03-25

Dichloromethane dehalogenase from Methylophilus sp. DM11 is a glutathione S-transferase homolog that is specifically active with dihalomethane substrates. This bacterial enzyme and rat liver glutathione S-transferases were purified to investigate their relative reactivity with CH2Cl2 and related substrates. Rat liver alpha class glutathione transferases were inactive and mu class enzymes showed low activity (7-23 nmol/min/mg of protein) with CH2Cl2. theta class glutathione transferase 5-5 from rat liver and Methylophilus sp. dichloromethane dehalogenase showed specific activities of > or = 1 mumol/min/mg of protein. Apparent Kcat/Km were determined to be 3.3 x 10(4) and 6.0 x 10(4) L M-1 S-1 for the two enzymes, respectively. Dideutero-dichloromethane was processed to dideutereo-formaldehyde, consistent with a nucleophilic halide displacement mechanism. The possibility of a GSCH2X reaction intermediate (GS, glutathione; X, halide) was probed using CH2ClF to generate a more stable halomethylglutathione species (GSCH2F). The reaction of CH2ClF with dichloromethane dehalogenase produced a kinetically identifiable intermediate that decomposed to formaldehyde at a similar rate to synthetic HOCH2CH2SCH2F. 19F-NMR revealed the transient formation of an intermediate identified as GSCH2F by its chemical shift, its triplet resonance, and H-F coupling constant consistent with a fluoromethylthioether. Its decomposition was matched by a stoichiometric formation of fluoride. These studies indicated that the bacterial dichloromethane dehalogenase directs a nucleophilic attack of glutathione on CH2Cl2 to produce a halomethylthioether intermediate. This focuses attention on the mechanism used by theta class glutathione transferases to generate a halomethylthioeter from relatively unreactive dihalomethanes.

Ursodeoxycholic Acid in Treatment of Non-cholestatic Liver Diseases: A Systematic Review.

PubMed

Reardon, Jillian; Hussaini, Trana; Alsahafi, Majid; Azalgara, Vladimir Marquez; Erb, Siegfried R; Partovi, Nilufar; Yoshida, Eric M

2016-09-28

Aims: To systematically evaluate the literature for evidence to support the use of bile acids in non-cholestatic liver conditions. Methods: Searches were conducted on the databases of Medline (1948-March 31, 2015), Embase (1980-March 31, 2015) and the Cochrane Central Register of Controlled Trials, and on Google and Google Scholar to identify articles describing ursodeoxycholic acid (UDCA) and its derivatives for non-cholestatic hepatic indications. Combinations of the following search terms were used: ursodeoxycholic acid, ursodiol, bile acids and/or salts, non alcoholic fatty liver, non alcoholic steatohepatitis, fatty liver, alcoholic hepatitis, alcohol, liver disease, autoimmune, autoimmune hepatitis, liver transplant, liver graft, transplant rejection, graft rejection, ischemic reperfusion injury, reperfusion injury, hepatitis B, hepatitis C, viral hepatitis, chronic hepatitis, acute hepatitis, transaminases, alanine transaminase, liver enzymes, aspartate aminotransferase, gamma-glutamyl transferase, gamma-glutamyl transpeptidase, bilirubin, alkaline phosphatase. No search limits were applied. Additionally, references of the included studies were reviewed to identify additional articles. Results: The literature search yielded articles meeting inclusion criteria for the following indications: non-alcoholic fatty liver disease (n = 5); alcoholic liver disease (n = 2); autoimmune hepatitis (n = 6), liver transplant (n = 2) and viral hepatitis (n = 9). Bile acid use was associated with improved normalization of liver biochemistry in non-alcoholic fatty liver disease, autoimmune hepatitis and hepatitis B and C infections. In contrast, liver biochemistry normalization was inconsistent in alcoholic liver disease and liver transplantation. The majority of studies reviewed showed that normalization of liver biochemistry did not correlate to improvement in histologic disease. In the prospective trials reviewed, adverse effects associated with the bile acids were limited

Ursodeoxycholic Acid in Treatment of Non-cholestatic Liver Diseases: A Systematic Review

PubMed Central

Reardon, Jillian; Hussaini, Trana; Alsahafi, Majid; Azalgara, Vladimir Marquez; Erb, Siegfried R.; Partovi, Nilufar; Yoshida, Eric M.

2016-01-01

Abstract Aims: To systematically evaluate the literature for evidence to support the use of bile acids in non-cholestatic liver conditions. Methods: Searches were conducted on the databases of Medline (1948-March 31, 2015), Embase (1980-March 31, 2015) and the Cochrane Central Register of Controlled Trials, and on Google and Google Scholar to identify articles describing ursodeoxycholic acid (UDCA) and its derivatives for non-cholestatic hepatic indications. Combinations of the following search terms were used: ursodeoxycholic acid, ursodiol, bile acids and/or salts, non alcoholic fatty liver, non alcoholic steatohepatitis, fatty liver, alcoholic hepatitis, alcohol, liver disease, autoimmune, autoimmune hepatitis, liver transplant, liver graft, transplant rejection, graft rejection, ischemic reperfusion injury, reperfusion injury, hepatitis B, hepatitis C, viral hepatitis, chronic hepatitis, acute hepatitis, transaminases, alanine transaminase, liver enzymes, aspartate aminotransferase, gamma-glutamyl transferase, gamma-glutamyl transpeptidase, bilirubin, alkaline phosphatase. No search limits were applied. Additionally, references of the included studies were reviewed to identify additional articles. Results: The literature search yielded articles meeting inclusion criteria for the following indications: non-alcoholic fatty liver disease (n = 5); alcoholic liver disease (n = 2); autoimmune hepatitis (n = 6), liver transplant (n = 2) and viral hepatitis (n = 9). Bile acid use was associated with improved normalization of liver biochemistry in non-alcoholic fatty liver disease, autoimmune hepatitis and hepatitis B and C infections. In contrast, liver biochemistry normalization was inconsistent in alcoholic liver disease and liver transplantation. The majority of studies reviewed showed that normalization of liver biochemistry did not correlate to improvement in histologic disease. In the prospective trials reviewed, adverse effects associated with the bile acids

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

PubMed Central

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

2014-01-01

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

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

PubMed

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

2017-06-19

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

Clinical utility of urine kidney injury molecule-1 (KIM-1) and gamma-glutamyl transferase (GGT) in the diagnosis of canine acute kidney injury.

PubMed

Lippi, Ilaria; Perondi, F; Meucci, V; Bruno, B; Gazzano, V; Guidi, G

2018-06-01

The aim of the present study was to evaluate the sensitivity and specificity of urine KIM-1 and urine GGT for the detection of naturally-occurring AKI, compared to healthy control dogs, dogs with stable chronic kidney disease (CKD), and dogs with lower urinary tract disorders (LUTD). The study included AKI grade 1 (n = 21), AKI grade 2 to 5 (n = 11), stable CKD (n = 11), LUTD (n = 15), and healthy dogs (n = 37). Urine KIM-1 (ng/mg) and GGT (U/l) were normalized to urine creatinine (uCr). Statistically significant difference in KIM/uCr (p = 0.0007) and GGT/uCr (p < 0.0001) was found among the study groups. Area under the curve (AUC) for KIM-1/uCr and GGT/uCr as predictors of AKI was 0.81 and 0.91 respectively. Values of KIM-1/uCr of 0.73 ng/mg and of GGT/uCr of 54.33 showed the best combination of sensitivity and specificity (75% and 75.6%; 85.7% and 89.1% respectively). A significant positive correlation (p < 0.0001) between KIM-1/uCr and GGT/uCr was found. Both urine KIM-1/uCr and GGT/uCr seemed to be potentially good markers for the diagnosis of AKI. Dogs with AKI showed significantly higher levels of urine KIM-1/uCr and urine GGT/uCr, compared with healthy dogs. Caution should be used in the evaluation of elevated urine KIM-1/uCr and GGT/uCr in dogs with pre-existing CKD and/or LUTD. Urine KIM-1/uCr and GGT/uCr might have a significant clinical utility, as complementary test, particularly in diagnosis early, non-azotemic stages of AKI.

A Conformational Investigation of Propeptide Binding to the Integral Membrane Protein γ-Glutamyl Carboxylase Using Nanodisc Hydrogen Exchange Mass Spectrometry

PubMed Central

2015-01-01

Gamma (γ)-glutamyl carboxylase (GGCX) is an integral membrane protein responsible for the post-translational catalytic conversion of select glutamic acid (Glu) residues to γ-carboxy glutamic acid (Gla) in vitamin K-dependent (VKD) proteins. Understanding the mechanism of carboxylation and the role of GGCX in the vitamin K cycle is of biological interest in the development of therapeutics for blood coagulation disorders. Historically, biophysical investigations and structural characterizations of GGCX have been limited due to complexities involving the availability of an appropriate model membrane system. In previous work, a hydrogen exchange mass spectrometry (HX MS) platform was developed to study the structural configuration of GGCX in a near-native nanodisc phospholipid environment. Here we have applied the nanodisc–HX MS approach to characterize specific domains of GGCX that exhibit structural rearrangements upon binding the high-affinity consensus propeptide (pCon; AVFLSREQANQVLQRRRR). pCon binding was shown to be specific for monomeric GGCX-nanodiscs and promoted enhanced structural stability to the nanodisc-integrated complex while maintaining catalytic activity in the presence of carboxylation co-substrates. Noteworthy modifications in HX of GGCX were prominently observed in GGCX peptides 491–507 and 395–401 upon pCon association, consistent with regions previously identified as sites for propeptide and glutamate binding. Several additional protein regions exhibited minor gains in solvent protection upon propeptide incorporation, providing evidence for a structural reorientation of the GGCX complex in association with VKD carboxylation. The results herein demonstrate that nanodisc–HX MS can be utilized to study molecular interactions of membrane-bound enzymes in the absence of a complete three-dimensional structure and to map dynamic rearrangements induced upon ligand binding. PMID:24512177

21 CFR 862.1315 - Galactose-1-phosphate uridyl transferase test system.

Code of Federal Regulations, 2010 CFR

2010-04-01

... of the enzyme galactose-1-phosphate uridyl transferase in erythrocytes (red blood cells... hereditary disease galactosemia (disorder of galactose metabolism) in infants. (b) Classification. Class II. ...

21 CFR 862.1315 - Galactose-1-phosphate uridyl transferase test system.

Code of Federal Regulations, 2014 CFR

2014-04-01

... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems § 862.1315 Galactose-1-phosphate uridyl transferase test system. (a) Identification...

21 CFR 862.1315 - Galactose-1-phosphate uridyl transferase test system.

Code of Federal Regulations, 2012 CFR

2012-04-01

... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems § 862.1315 Galactose-1-phosphate uridyl transferase test system. (a) Identification...

21 CFR 862.1535 - Ornithine carbamyl transferase test system.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Ornithine carbamyl transferase test system. 862.1535 Section 862.1535 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry...

Homogentisate solanesyl transferase (HST) cDNA’s in maize

USDA-ARS?s Scientific Manuscript database

Maize white seedling 3 (w3) has served as a model albino-seedling mutant since its discovery in 1923. We show that the w3 phenotype is caused by disruptions in homogentisate solanesyl transferase (HST), an enzyme that catalyzes the committed step in plastoquinone-9 (PQ9) biosynthesis. This reaction ...

Reversal of hypermethylation and reactivation of glutathione S-transferase pi 1 gene by curcumin in breast cancer cell line.

PubMed

Kumar, Umesh; Sharma, Ujjawal; Rathi, Garima

2017-02-01

One of the mechanisms for epigenetic silencing of tumor suppressor genes is hypermethylation of cytosine residue at CpG islands at their promoter region that contributes to malignant progression of tumor. Therefore, activation of tumor suppressor genes that have been silenced by promoter methylation is considered to be very attractive molecular target for cancer therapy. Epigenetic silencing of glutathione S-transferase pi 1, a tumor suppressor gene, is involved in various types of cancers including breast cancer. Epigenetic silencing of tumor suppressor genes can be reversed by several molecules including natural compounds such as polyphenols that can act as a hypomethylating agent. Curcumin has been found to specifically target various tumor suppressor genes and alter their expression. To check the effect of curcumin on the methylation pattern of glutathione S-transferase pi 1 gene in MCF-7 breast cancer cell line in dose-dependent manner. To check the reversal of methylation pattern of hypermethylated glutathione S-transferase pi 1, MCF-7 breast cancer cell line was treated with different concentrations of curcumin for different time periods. DNA and proteins of treated and untreated cell lines were isolated, and methylation status of the promoter region of glutathione S-transferase pi 1 was analyzed using methylation-specific polymerase chain reaction assay, and expression of this gene was analyzed by immunoblotting using specific antibodies against glutathione S-transferase pi 1. A very low and a nontoxic concentration (10 µM) of curcumin treatment was able to reverse the hypermethylation and led to reactivation of glutathione S-transferase pi 1 protein expression in MCF-7 cells after 72 h of treatment, although the IC 50 value of curcumin was found to be at 20 µM. However, curcumin less than 3 µM of curcumin could not alter the promoter methylation pattern of glutathione S-transferase pi 1. Treatment of breast cancer MCF-7 cells with curcumin

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

PubMed

Adaramoye, Oluwatosin A; Akanni, Olubukola O

2016-01-01

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

A randomized controlled trial of Moderation-Oriented Cue Exposure.

PubMed

Heather, N; Brodie, J; Wale, S; Wilkinson, G; Luce, A; Webb, E; McCarthy, S

2000-07-01

A randomized controlled trial was conducted to examine the effectiveness of Moderation-Oriented Cue Exposure (MOCE) in comparison to Behavioral Self-Control Training (BSCT). The main hypothesis was that MOCE would be more effective than BSCT among a sample of problem drinkers aiming at moderate drinking. A subsidiary hypothesis was that MOCE would be relatively more effective than BSCT among problem drinkers with higher levels of alcohol dependence. Clients (N = 91; 75% men) were randomly allocated to either MOCE or BSCT. Treatment was delivered in weekly sessions by two trained therapists, in a nested design in which therapists switched to the alternative treatment modality approximately halfway through the trial. Follow-up was carried out 6 months following posttreatment assessment, with 85% successful contact. There was no evidence for the general superiority of MOCE over BSCT. The subsidiary hypothesis was not confirmed. A subsample of clients (n = 14) showing levels of dependence at baseline above the commonly accepted cut-point for a moderation goal (Severity of Alcohol Dependence Questionnaire [SADQ] > 29) showed outcomes at least as favorable as those below the cut-point. The validity of self-reports of alcohol consumption and problems was supported by significant relationships with liver function tests (gamma-glutamyl transferase and alanine transferase). These results provide no grounds for the replacement of BSCT by MOCE in routine, moderation-oriented treatment practice. Assuming they prefer it to abstinence and that it is not contra-indicated on other grounds, there seems no reason why clients showing a higher level of dependence (SADQ = 30-45) should not be offered a moderation goal.

The correlates of urinary albumin to creatinine ratio (ACR) in a high risk Australian aboriginal community.

PubMed

Wang, Zaimin; Hoy, Wendy E; Wang, Zhiqiang

2013-08-16

Albuminuria marks renal disease and cardiovascular risk. It was estimated to contribute 75% of the risk of all-cause natural death in one Aboriginal group. The urine albumin/creatinine ratio (ACR) is commonly used as an index of albuminuria. This study aims to examine the associations between demographic factors, anthropometric index, blood pressure, lipid-protein measurements and other biomarkers and albuminuria in a cross-sectional study in a high-risk Australian Aboriginal population. The models will be evaluated for albuminuria at or above the microalbuminuria threshold, and at or above the "overt albuminuria" threshold with the potential to distinguish associations they have in common and those that differ. This was a cross-sectional study of 598 adults aged 18-76 years. All participants were grouped into quartiles by age. Logistic regression models were used to explore the correlates of ACR categories. The significant correlates were systolic blood pressure (SBP), C-reactive protein (CRP), uric acid, diabetes, gamma-glutamyl transferase (GGT) (marginally significant, p=0.054) and serum albumin (negative association) for ACR 17+ (mg/g) for men and 25+ for women. Independent correlates were SBP, uric acid, diabetes, total cholesterol, alanine amino transferase (ALT), Cystatin C and serum albumin (negative association) for overt albuminuria; and SBP, CRP and serum albumin only for microalbuminuria. This is the most detailed modelling of pathologic albuminuria in this setting to date. The somewhat variable association with risk factors suggests that microalbuminuria and overt albuminuria might reflect different as well as shared phenomena.

Evaluation of liver enzyme levels and identification of asymptomatic liver disease patients in primary care.

PubMed

Cacciola, Irene; Scoglio, Riccardo; Alibrandi, Angela; Squadrito, Giovanni; Raimondo, Giovanni

2017-03-01

The evaluation of serum liver enzyme levels is the most used surrogate marker of liver injury in clinical practice. The prevalence and association of abnormal enzyme values with hepatitis B virus (HBV) and hepatitis C virus (HCV) infections, and with other major causes of liver damage (obesity, diabetes, dyslipidemia, and alcohol abuse) were evaluated in individuals attending the surgeries of 14 general practitioners (GPs) working in Messina. Alanine-amino-transferase, aspartate-amino-transferase, and gamma-glutamyl-transpeptidase measurements were measured in 7816 individuals consecutively attending the GP surgeries between January 1, 2011 and June 30, 2012. Five-thousand-eight-hundred-six subjects (74.3 %) had the tests performed, and 1189 of them (20.5 %) showed increased liver enzyme levels. Sixty-nine of these 1189 individuals (5.8 %) were HCV positive and 12 HBV positive (1 %), 755 (63.5 %) were overweight or obese, 288 (24.2 %) had diabetes, and 351 (29.5 %) had dyslipidemia; 262 (22 %) drank >2 alcoholic units/day. Overall, 57 % of individuals with abnormal liver enzymes had multiple possible causes of liver disease, 28 % one cause, and 15 % no apparent cause. In conclusion, this study shows that 1/5 of individuals attending GP surgeries have altered liver biochemistry and that overweight and metabolic disorders have become the major causes of liver damage even in South Italy, where HBV and HCV were endemic in the past century. Notably, many HCV and HBV patients are still unaware of their infected status, and GPs are essential for their timely identification.

Functional Dissection of the Bipartite Active Site of the Class I Coenzyme A (CoA)-Transferase Succinyl-CoA:Acetate CoA-Transferase.

PubMed

Murphy, Jesse R; Mullins, Elwood A; Kappock, T Joseph

2016-01-01

Coenzyme A (CoA)-transferases catalyze the reversible transfer of CoA from acyl-CoA thioesters to free carboxylates. Class I CoA-transferases produce acylglutamyl anhydride intermediates that undergo attack by CoA thiolate on either the internal or external carbonyl carbon atoms, forming distinct tetrahedral intermediates <3 Å apart. In this study, crystal structures of succinyl-CoA:acetate CoA-transferase (AarC) from Acetobacter aceti are used to examine how the Asn347 carboxamide stabilizes the internal oxyanion intermediate. A structure of the active mutant AarC-N347A bound to CoA revealed both solvent replacement of the missing contact and displacement of the adjacent Glu294, indicating that Asn347 both polarizes and orients the essential glutamate. AarC was crystallized with the nonhydrolyzable acetyl-CoA (AcCoA) analog dethiaacetyl-CoA (1a) in an attempt to trap a closed enzyme complex containing a stable analog of the external oxyanion intermediate. One active site contained an acetylglutamyl anhydride adduct and truncated 1a, an unexpected result hinting at an unprecedented cleavage of the ketone moiety in 1a. Solution studies confirmed that 1a decomposition is accompanied by production of near-stoichiometric acetate, in a process that seems to depend on microbial contamination but not AarC. A crystal structure of AarC bound to the postulated 1a truncation product (2a) showed complete closure of one active site per dimer but no acetylglutamyl anhydride, even with acetate added. These findings suggest that an activated acetyl donor forms during 1a decomposition; a working hypothesis involving ketone oxidation is offered. The ability of 2a to induce full active site closure furthermore suggests that it subverts a system used to impede inappropriate active site closure on unacylated CoA.

Functional Dissection of the Bipartite Active Site of the Class I Coenzyme A (CoA)-Transferase Succinyl-CoA:Acetate CoA-Transferase

PubMed Central

Murphy, Jesse R.; Mullins, Elwood A.; Kappock, T. Joseph

2016-01-01

Coenzyme A (CoA)-transferases catalyze the reversible transfer of CoA from acyl-CoA thioesters to free carboxylates. Class I CoA-transferases produce acylglutamyl anhydride intermediates that undergo attack by CoA thiolate on either the internal or external carbonyl carbon atoms, forming distinct tetrahedral intermediates <3 Å apart. In this study, crystal structures of succinyl-CoA:acetate CoA-transferase (AarC) from Acetobacter aceti are used to examine how the Asn347 carboxamide stabilizes the internal oxyanion intermediate. A structure of the active mutant AarC-N347A bound to CoA revealed both solvent replacement of the missing contact and displacement of the adjacent Glu294, indicating that Asn347 both polarizes and orients the essential glutamate. AarC was crystallized with the nonhydrolyzable acetyl-CoA (AcCoA) analog dethiaacetyl-CoA (1a) in an attempt to trap a closed enzyme complex containing a stable analog of the external oxyanion intermediate. One active site contained an acetylglutamyl anhydride adduct and truncated 1a, an unexpected result hinting at an unprecedented cleavage of the ketone moiety in 1a. Solution studies confirmed that 1a decomposition is accompanied by production of near-stoichiometric acetate, in a process that seems to depend on microbial contamination but not AarC. A crystal structure of AarC bound to the postulated 1a truncation product (2a) showed complete closure of one active site per dimer but no acetylglutamyl anhydride, even with acetate added. These findings suggest that an activated acetyl donor forms during 1a decomposition; a working hypothesis involving ketone oxidation is offered. The ability of 2a to induce full active site closure furthermore suggests that it subverts a system used to impede inappropriate active site closure on unacylated CoA. PMID:27242998

Functional dissection of the bipartite active site of the class I coenzyme A (CoA)-transferase succinyl-CoA:acetate CoA-transferase

DOE PAGES

Murphy, Jesse R.; Mullins, Elwood A.; Kappock, T. Joseph

2016-05-23

Coenzyme A (CoA)-transferases catalyze the reversible transfer of CoA from acyl-CoA thioesters to free carboxylates. Class I CoA-transferases produce acylglutamyl anhydride intermediates that undergo attack by CoA thiolate on either the internal or external carbonyl carbon atoms, forming distinct tetrahedral intermediates <3 Å apart. Here in this study, crystal structures of succinyl-CoA:acetate CoA-transferase (AarC) from Acetobacter aceti are used to examine how the Asn347 carboxamide stabilizes the internal oxyanion intermediate. A structure of the active mutant AarC-N347A bound to CoA revealed both solvent replacement of the missing contact and displacement of the adjacent Glu294, indicating that Asn347 both polarizes andmore » orients the essential glutamate. AarC was crystallized with the nonhydrolyzable acetyl-CoA (AcCoA) analog dethiaacetyl-CoA (1a) in an attempt to trap a closed enzyme complex containing a stable analog of the external oxyanion intermediate. One active site contained an acetylglutamyl anhydride adduct and truncated 1a, an unexpected result hinting at an unprecedented cleavage of the ketone moiety in 1a. Solution studies confirmed that 1a decomposition is accompanied by production of near-stoichiometric acetate, in a process that seems to depend on microbial contamination but not AarC. A crystal structure of AarC bound to the postulated 1a truncation product (2a) showed complete closure of one active site per dimer but no acetylglutamyl anhydride, even with acetate added. These findings suggest that an activated acetyl donor forms during 1a decomposition; a working hypothesis involving ketone oxidation is offered. Finally, the ability of 2a to induce full active site closure furthermore suggests that it subverts a system used to impede inappropriate active site closure on unacylated CoA.« less

Divergent effects of compounds on the hydrolysis and transpeptidation reactions of γ-glutamyl transpeptidase.

PubMed

Wickham, Stephanie; Regan, Nicholas; West, Matthew B; Kumar, Vidya Prasanna; Thai, Justin; Li, Pui Kai; Cook, Paul F; Hanigan, Marie H

2012-08-01

A novel class of inhibitors of the enzyme γ-glutamyl transpeptidase (GGT) were evaluated. The analog OU749 was shown previously to be an uncompetitive inhibitor of the GGT transpeptidation reaction. The data in this study show that it is an equally potent uncompetitive inhibitor of the hydrolysis reaction, the primary reaction catalyzed by GGT in vivo. A series of structural analogs of OU749 were evaluated. For many of the analogs, the potency of the inhibition differed between the hydrolysis and transpeptidation reactions, providing insight into the malleability of the active site of the enzyme. Analogs with electron withdrawing groups on the benzosulfonamide ring, accelerated the hydrolysis reaction, but inhibited the transpeptidation reaction by competing with a dipeptide acceptor. Several of the OU749 analogs inhibited the transpeptidation reaction by slow onset kinetics, similar to acivicin. Further development of inhibitors of the GGT hydrolysis reaction is necessary to provide new therapeutic compounds.

Relationship among blood indicators of lipomobilization and hepatic function during early lactation in high-yielding dairy cows.

PubMed

González, Felix Diaz; Muiño, Rodrigo; Pereira, Víctor; Campos, Rómulo; Benedito, José Luis

2011-09-01

Blood indicators are used as a tool to diagnose metabolic disorders. The present work was conducted to study the relationships among blood indicators of lipomobilization and hepatic function in high-yielding dairy cows. Two groups of Holstein cows were studied: 27 early lactation cows and 14 mid lactation cows from four different herds with similar husbandry characteristics in Galicia, Spain. Blood samples were obtained to measure beta-hydroxybutyrate (BHB), non-esterified fatty acids (NEFA), triglycerides (TG), and the activity of aspartate transaminase (AST) and gamma-glutamyl transferase. Cows in early lactation had higher levels of BHB and NEFA than mid lactation cows. High lipomobilization (NEFA > 400 µmol/L) was detected in 67% and 7% of early lactation and mid lactation cows, respectively, while subclinical ketosis (BHB > 1.2 mmol/L) was detected in 41% and 28% of the early lactation and lactation cows, respectively. TG concentrations were low in all cows suffering subclinical ketosis and in 61% of the cows with high lipomobilization. During early lactation, 30% of cows suffered hepatic lipidosis as detected by levels of AST. Compromised hepatic function was observed in early lactation cows as shown by lower concentrations of glucose, total protein, and urea.

Influence of Piper betle on hepatic marker enzymes and tissue antioxidant status in D-galactosamine-induced hepatotoxic rats.

PubMed

Pushpavalli, Ganesan; Veeramani, Chinnadurai; Pugalendi, Kodukkur Viswanathan

2008-01-01

D-galactosamine is a well-established hepatotoxicant that induces a diffuse type of liver injury closely resembling human viral hepatitis. D-galactosamine by its property of generating free radicals causes severe damage to the membrane and affects almost all organs of the human body. The leaves of Piper betle L., a commonly used masticatory in Asian countries, possess several biological properties. Our aim is to investigate the in vivo antioxidant potential of P. betle leaf-extract against oxidative stress induced by D-galactosamine intoxication in male albino Wistar rats. Toxicity was induced by an intraperitoneal injection of D-galactosamine, 400 mg/kg body weight (BW) for 21 days. Rats were treated with P. betle extract (200 mg/kg BW) via intragastric intubations. We assessed the activities of liver marker enzymes (aspartate amino-transferase, alanine aminotransferase, alkaline phosphatase, gamma glutamyl transpeptidase) and levels of thiobarbituric acid reactive substances (TBARS), lipid hydroperoxides, superoxide dismutase, catalase, glutathione peroxidase, vitamin C, vitamin E, and reduced glutathione. The extract significantly improved the status of antioxidants and decreased TBARS, hydroperoxides, and liver marker enzymes when compared with the D-galactosamine treated group, demonstrating its hepatoprotective and antioxidant properties.

Relative tumour promoting activity of three polychlorinated biphenyls in rat liver.

PubMed

Hemming, H; Flodström, S; Wärngård, L; Bergman, A; Kronevi, T; Nordgren, I; Ahlborg, U G

1993-08-02

The relative tumour promoting activity of three structurally and toxicologically diverse polychlorinated biphenyls (3,4,5,3',4'-penta- 2,3,4,3',4'-penta- and 2,4,5,2',4',5'-hexachlorobiphenyl) was measured in an initiation/promotion assay in nitrosodiethylamine-initiated female Sprague-Dawley rats. The congeners under study were administered by once-weekly subcutaneous injections for 20 weeks. Evaluation of the development of gamma-glutamyl transpeptidase (GGT)- and glutation transferase P (GST-P)-positive hepatic foci showed that all congeners promoted altered hepatic foci, although 3,4,5,3',4'-pentachlorobiphenyl was far more potent. The volume fraction of the liver occupied by GGT-positive tissue in the 3,4,5,3',4'-pentachlorobiphenyl-treated animals (100 micrograms/kg per week) was 23%, while the volume fractions of altered liver tissue in the rats treated with 2,3,4,3',4'-pentachlorobiphenyl (5000 micrograms/kg per week) and 2,4,5,2',4',5'-hexaCB (20,000 micrograms/kg per week) were 1.2 and 2.3, respectively. The enhancement of GGT- and GST-P-positive foci was accompanied by an increased incidence of histological changes in the livers.

Effect of tea (Camellia sinensis) and olive (Olea europaea L.) leaves extracts on male mice exposed to diazinon.

PubMed

Al-Attar, Atef M; Abu Zeid, Isam M

2013-01-01

The present study was aimed to evaluate the effects of tea and olive leaves extracts and their combination in male mice intoxicated with a sublethal concentration of diazinon. Exposure of mice to 6.5 mg/kg body weight of diazinon for seven weeks resulted in statistical increases of serum alanine aminotransferase, aspartate aminotransferase, gamma glutamyl transferase, alkaline phosphatase, creatine kinase, creatinine, glucose, triglycerides, and cholesterol, while the value of serum total protein was declined. Treating diazinon-intoxicated mice with tea and olive leaves extracts or their combination significantly attenuated the severe alterations in these hematobiochemical parameters. Moreover, the results indicated that the supplementation with combination of tea and olive leaves extracts led to more attenuation effect against diazinon toxicity. Additionally, these new findings suggest that the effect of tea and olive leaves extracts and their combination against toxicity of diazinon may be due to antioxidant properties of their chemical constituents. Finally, the present study indicated that the extracts of tea and olive leaves and their combination can be considered as promising therapeutic agents against hepatotoxicity, cardiotoxicity, nephrotoxicity, and metabolic disorders induced by diazinon and maybe by other toxicants and pathogenic factors.

Effect of Tea (Camellia sinensis) and Olive (Olea europaea L.) Leaves Extracts on Male Mice Exposed to Diazinon

PubMed Central

Al-Attar, Atef M.; Abu Zeid, Isam M.

2013-01-01

The present study was aimed to evaluate the effects of tea and olive leaves extracts and their combination in male mice intoxicated with a sublethal concentration of diazinon. Exposure of mice to 6.5 mg/kg body weight of diazinon for seven weeks resulted in statistical increases of serum alanine aminotransferase, aspartate aminotransferase, gamma glutamyl transferase, alkaline phosphatase, creatine kinase, creatinine, glucose, triglycerides, and cholesterol, while the value of serum total protein was declined. Treating diazinon-intoxicated mice with tea and olive leaves extracts or their combination significantly attenuated the severe alterations in these hematobiochemical parameters. Moreover, the results indicated that the supplementation with combination of tea and olive leaves extracts led to more attenuation effect against diazinon toxicity. Additionally, these new findings suggest that the effect of tea and olive leaves extracts and their combination against toxicity of diazinon may be due to antioxidant properties of their chemical constituents. Finally, the present study indicated that the extracts of tea and olive leaves and their combination can be considered as promising therapeutic agents against hepatotoxicity, cardiotoxicity, nephrotoxicity, and metabolic disorders induced by diazinon and maybe by other toxicants and pathogenic factors. PMID:23691503

Dose-effect relation between daily ethanol intake in the range 0-70 grams and %CDT value: validation of a cut-off value.

PubMed

Schellenberg, François; Schwan, Raymund; Mennetrey, Louise; Loiseaux, Marie-Nadia; Pagès, Jean Christophe; Reynaud, Michel

2005-01-01

To evaluate the ability to infer alcohol consumption using the %CDT (carbohydrate deficient transferrin) immunoassay (Axis Shield). One hundred and eighty-three healthy subjects (143 men, 40 women) undergoing a routine medical check-up at their workplace declared frequency and quantity of alcohol consumption covering the last 4 weeks. Seven sub-groups were made up from this population, according to daily ethanol intake and by increments of 10 g from 0 to 70 g/day. A reference group that consisted of 133 healthy teetotallers (74 men, 59 women) was recruited by occupational medicine in the same conditions as the 183 subjects of the study. Percentage CDT and gamma glutamyl transferase (GGT) were assayed on a fasting blood sample. There was a proportional dose-response effect of daily ethanol intake on %CDT values in the range of 0-70 g per day. A threshold effect on %CDT values for patients having an alcohol intake of over 40 g per day was found, an effect which was not observed for GGT activity. The kit has clinical usefulness, and the value of 2.6% proposed by the manufacturer for the cut-off for hazardous drinking in both sexes has been validated.

The protective role of quercetin and arginine on gold nanoparticles induced hepatotoxicity in rats.

PubMed

Abdelhalim, Mohamed Anwar K; Moussa, Sherif A Abdelmottaleb; Qaid, Huda Abdo Yahya

2018-01-01

The aim of the study was to confirm the hepatotoxicity induced by small-sized gold nanoparticles (GNPs) and evaluate the role of quercetin (Qur) and arginine (Arg) against hepatotoxicity caused by GNPs. Twenty-five healthy male Wistar-Kyoto rats were used. GNPs were administered intraperitoneally to these rats at the dose of 50 μL for seven consecutive days. The role of Qur and Arg antioxidants against toxicity induced by GNPs was detected through the measurement of serum liver function and oxidative stress biomarkers in the liver tissues. Coadministration of Qur and Arg along with GNPs significantly induced dramatic alterations in the biochemical parameters. Levels of malondialdehyde, gamma-glutamyl transferase, alanine aminotransferase, alkaline phosphatase, and total protein increased significantly in the GNPs injected group than in the control group, while reduced glutathione was greatly reduced in the GNPs group than in the control group. It also significantly decreased liver enzymes and the oxidative stress, therefore improving the liver damage and hepatotoxicity induced by GNPs. This study demonstrated that Qur and Arg antioxidants effectively improved the hepatic oxidative damage induced by GNPs. It also substantiates the application of Qur and Arg as protecting stand-in against GNPs' hepatotoxicity.

Blood Chemistry Reference Values for Free-Ranging Asiatic Black Bears ( Ursus thibetanus) by Season, Age, and Sex.

PubMed

Yang, Jeong-Jin; Jeong, Dong-Hyuk; Lim, Yoon-Kyu

2018-04-19

Physiological characteristics, such as blood chemistry values, are valuable for evaluating the health of the animals. To our knowledge, these values have never been reported for the free-ranging Asiatic black bear ( Ursus thibetanus; ABB). Thus, 28 blood chemistry values from 50 free-ranging ABBs captured in Jirisan National Park, Republic of Korea, from 2005 to 2016 were evaluated. The aim of this study was to establish blood chemistry reference values for the free-ranging ABBs during both the hibernating and nonhibernating seasons. During hibernation, mean values of creatinine (CRE), total cholesterol, total protein (TP), albumin (ALB), triglycerides, and Mg were significantly higher than those during nonhibernation; however, mean values of blood urea nitrogen, urea nitrogen to creatinine (U/C) ratio, inorganic phosphorous (IP), aspartate aminotransferase, alanine aminotransferase, gamma-glutamyl transferase, lactate dehydrogenase (LDH), high-density lipoprotein cholesterol, and alkaline phosphatase (ALP) were significantly lower. Age differences (young vs. adult) were found in IP, LDH, TP, and ALB values during hibernation and in the U/C ratio, Ca, IP, ALP, creatine kinase myocardial band, CRE, total bilirubin, and uric acid values during nonhibernation. However, there were no sex differences (male vs. female).

Chemical composition and biological evaluation of Physalis peruviana root as hepato-renal protective agent.

PubMed

El-Gengaihi, Souad E; Hassan, Emad E; Hamed, Manal A; Zahran, Hanan G; Mohammed, Mona A

2013-03-01

This study was designed to investigate the potential of Physalis peruviana root as a functional food with hepato-renal protective effects against fibrosis. The chemical composition of the plant root suggested the presence of alkaloids, withanolides and flavonoids. Five compounds were isolated and their structures elucidated by different spectral analysis techniques. One compound was isolated from the roots: cuscohygrine. The biological evaluation was conducted on different animal groups; control rats, control treated with ethanolic root extract, CCl(4) group, CCl(4) treated with root extract, and CCl(4) treated with silymarin as a standard herbal drug. The evaluation used the oxidative stress markers malondialdehyde (MDA), superoxide dismutase (SOD), and nitric oxide (NO). The liver function indices; aspartate and alanine aminotransferases (AST & ALT), alkaline phosphatase (ALP), gamma glutamyl transferase (GGT), bilirubin, and total hepatic protein were also estimated. Kidney disorder biomarkers; creatinine, urea, and serum protein were also evaluated. The results suggested safe administration, and improvement of all the investigated parameters. The liver and kidney histopathological analysis confirmed the results. In conclusion, P. peruviana succeeded in protecting the liver and kidney against fibrosis. Further studies are needed to discern their pharmacological applications and clinical uses.

Zingiber officinale acts as a nutraceutical agent against liver fibrosis

PubMed Central

2011-01-01

Background/objective Zingiber officinale Roscoe (ginger) (Zingiberaceae) has been cultivated for thousands of years both as a spice and for medicinal purposes. Ginger rhizomes successive extracts (petroleum ether, chloroform and ethanol) were examined against liver fibrosis induced by carbon tetrachloride in rats. Results The evaluation was done through measuring antioxidant parameters; glutathione (GSH), total superoxide dismutase (SOD) and malondialdehyde (MDA). Liver marker enzymes; succinate and lactate dehydrogenases (SDH and LDH), glucose-6-phosphatase (G-6-Pase), acid phosphatase (AP), 5'- nucleotidase (5'NT) and liver function enzymes; aspartate and alanine aminotransferases (AST and ALT) as well as cholestatic markers; alkaline phosphatase (ALP), gamma glutamyl transferase (GGT), total bilirubin were estimated. Liver histopathological analysis and collagen content were also evaluated. Treatments with the selected extracts significantly increased GSH, SOD, SDH, LDH, G-6-Pase, AP and 5'NT. However, MDA, AST, ALT ALP, GGT and total bilirubin were significantly decreased. Conclusions Extracts of ginger, particularly the ethanol one resulted in an attractive candidate for the treatment of liver fibrosis induced by CCl4. Further studies are required in order to identify the molecules responsible of the pharmacological activity. PMID:21689445

Heat-Killed Lactobacillus salivarius and Lactobacillus johnsonii Reduce Liver Injury Induced by Alcohol In Vitro and In Vivo.

PubMed

Chuang, Cheng-Hung; Tsai, Cheng-Chih; Lin, En-Shyh; Huang, Chin-Shiu; Lin, Yun-Yu; Lan, Chuan-Ching; Huang, Chun-Chih

2016-10-31

The aim of the present study was to determine whether Lactobacillus salivarius (LS) and Lactobacillus johnsonii (LJ) prevent alcoholic liver damage in HepG2 cells and rat models of acute alcohol exposure. In this study, heat-killed LS and LJ were screened from 50 Lactobacillus strains induced by 100 mM alcohol in HepG2 cells. The severity of alcoholic liver injury was determined by measuring the levels of aspartate transaminase (AST), alanine transaminase (ALT), gamma-glutamyl transferase (γ-GT), lipid peroxidation, triglyceride (TG) and total cholesterol. Our results indicated that heat-killed LS and LJ reduced AST, ALT, γ-GT and malondialdehyde (MDA) levels and outperformed other bacterial strains in cell line studies. We further evaluated these findings by administering these strains to rats. Only LS was able to reduce serum AST levels, which it did by 26.2%. In addition LS significantly inhibited serum TG levels by 39.2%. However, both strains were unable to inhibit ALT levels. In summary, we demonstrated that heat-killed LS and LJ possess hepatoprotective properties induced by alcohol both in vitro and in vivo.

21 CFR 573.130 - Aminoglycoside 3′-phospho- transferase II.

Code of Federal Regulations, 2012 CFR

2012-04-01

... SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES PERMITTED IN FEED AND DRINKING WATER OF ANIMALS Food Additive Listing § 573.130 Aminoglycoside 3′-phospho- transferase II. The food additive aminoglycoside 3′-phosphotransferase II may be safely used in the development of...

21 CFR 573.130 - Aminoglycoside 3′-phospho- transferase II.

Code of Federal Regulations, 2010 CFR

2010-04-01

... SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES PERMITTED IN FEED AND DRINKING WATER OF ANIMALS Food Additive Listing § 573.130 Aminoglycoside 3′-phospho- transferase II. The food additive aminoglycoside 3′-phosphotransferase II may be safely used in the development of...

21 CFR 573.130 - Aminoglycoside 3′-phospho- transferase II.

Code of Federal Regulations, 2013 CFR

2013-04-01

... SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES PERMITTED IN FEED AND DRINKING WATER OF ANIMALS Food Additive Listing § 573.130 Aminoglycoside 3′-phospho- transferase II. The food additive aminoglycoside 3′-phosphotransferase II may be safely used in the development of...

21 CFR 573.130 - Aminoglycoside 3′-phospho- transferase II.

Code of Federal Regulations, 2011 CFR

2011-04-01

... SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES PERMITTED IN FEED AND DRINKING WATER OF ANIMALS Food Additive Listing § 573.130 Aminoglycoside 3′-phospho- transferase II. The food additive aminoglycoside 3′-phosphotransferase II may be safely used in the development of...

21 CFR 573.130 - Aminoglycoside 3′-phospho- transferase II.

Code of Federal Regulations, 2014 CFR

2014-04-01

... SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES PERMITTED IN FEED AND DRINKING WATER OF ANIMALS Food Additive Listing § 573.130 Aminoglycoside 3′-phospho- transferase II. The food additive aminoglycoside 3′-phosphotransferase II may be safely used in the development of...

Extract of Xylopia aethiopica (Annonaceae) protects against gamma-radiation induced testicular damage in Wistar rats.

PubMed

Adaramoye, Oluwatosin Adekunle; Adedara, Isaac Adegboyega; Popoola, Bosede; Farombi, Ebenezer Olatunde

2010-01-01

Ionizing radiation is an important environmental risk factor and, a major therapeutic agent for cancer treatment. This study was designed to evaluate the protective effect of extract of Xylopia aethiopica (XA) on gamma-radiation-induced testicular damage in rats. Vitamin C (VC) served as the reference antioxidant during the study. The study consists of 4 groups of 11 rats each. Group I received corn oil (vehicle), groups II and IV were pretreated with XA (250 mg/kg) and VC (250mg/kg) for 6 weeks before and 8 weeks after exposure to gamma-radiation; group III was exposed to a single dose of gamma-radiation (5 Gy). Biochemical analysis revealed that gamma-irradiation caused a significant increase (p < .05) in serum and testicular lipid peroxidation (LPO) levels by 217% and 221%, respectively. Irradiated rats had markedly decreased testicular catalase (CAT), superoxide dismutase (SOD), glutathione-S-transferase (GST), and reduced glutathione (GSH) levels. Irradiation resulted in 59% and 40% decreases in spermatozoa motility and live/dead sperm count, respectively, and a 161% increase in total sperm abnormalities. Histologically, testes of the irradiated rats showed extensive degenerative changes in the seminiferous tubules and defoliation of spermatocytes. Supplementation of XA and VC reversed the adverse effects of gamma-radiation on biochemical and histological indices of the rats. These findings demonstrated that Xylopia aethiopica has a protective effect by inhibiting oxidative damage in testes of irradiated rats.

Succinyl-CoA:(R)-Benzylsuccinate CoA-Transferase: an Enzyme of the Anaerobic Toluene Catabolic Pathway in Denitrifying Bacteria†

PubMed Central

Leutwein, Christina; Heider, Johann

2001-01-01

Anaerobic microbial toluene catabolism is initiated by addition of fumarate to the methyl group of toluene, yielding (R)-benzylsuccinate as first intermediate, which is further metabolized via β-oxidation to benzoyl-coenzyme A (CoA) and succinyl-CoA. A specific succinyl-CoA:(R)-benzylsuccinate CoA-transferase activating (R)-benzylsuccinate to the CoA-thioester was purified and characterized from Thauera aromatica. The enzyme is fully reversible and forms exclusively the 2-(R)-benzylsuccinyl-CoA isomer. Only some close chemical analogs of the substrates are accepted by the enzyme: succinate was partially replaced by maleate or methylsuccinate, and (R)-benzylsuccinate was replaced by methylsuccinate, benzylmalonate, or phenylsuccinate. In contrast to all other known CoA-transferases, the enzyme consists of two subunits of similar amino acid sequences and similar sizes (44 and 45 kDa) in an α2β2 conformation. Identity of the subunits with the products of the previously identified toluene-induced bbsEF genes was confirmed by determination of the exact masses via electrospray-mass spectrometry. The deduced amino acid sequences resemble those of only two other characterized CoA-transferases, oxalyl-CoA:formate CoA-transferase and (E)-cinnamoyl-CoA:(R)-phenyllactate CoA-transferase, which represent a new family of CoA-transferases. As suggested by kinetic analysis, the reaction mechanism of enzymes of this family apparently involves formation of a ternary complex between the enzyme and the two substrates. PMID:11418570

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

PubMed

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

2002-08-16

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

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

ERIC Educational Resources Information Center

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

2011-01-01

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

The NEXT-A (N-terminal EXtension with Transferase and ARS) reaction.

PubMed

Taki, Masumi; Kuroiwa, Hiroyuki; Sisido, Masahiko

2009-01-01

L/F-transferase is known to catalyze transfer of hydrophobic amino acids from aminoacyl tRNA to the N-terminus of a protein possessing lysine or arginine as the N-terminus. Combining L/F-transferase with E. coli phenylalanyl-tRNA synthetase (ARS), we achieved non-ribosomal N-terminal-specific introduction of various kinds of nonnatural amino acids to a protein. A nonnatural amino acid is once charged onto an E. coli tRNA(Phe) by a mutant ARS in situ, and successively transferred from the tRNA to a target protein, namely the NEXT-A reaction. Besides alphaA294G mutation on the ARS, alphaT251A, betaG318W, or betaA356W double-mutation were effective to increase the introduction efficiency through the NEXT-A reaction. Protein specific fluorescence labelling via the NEXT-A reaction followed by Huisgen cycloaddition was also demonstrated.

Prolonged fasting increases glutathione biosynthesis in postweaned northern elephant seals.

PubMed

Vázquez-Medina, José Pablo; Zenteno-Savín, Tania; Forman, Henry Jay; Crocker, Daniel E; Ortiz, Rudy M

2011-04-15

Northern elephant seals experience prolonged periods of absolute food and water deprivation (fasting) while breeding, molting or weaning. The postweaning fast in elephant seals is characterized by increases in the renin-angiotensin system, expression of the oxidant-producing protein Nox4, and NADPH oxidase activity; however, these increases are not correlated with increased oxidative damage or inflammation. Glutathione (GSH) is a potent reductant and a cofactor for glutathione peroxidases (GPx), glutathione-S transferases (GST) and 1-cys peroxiredoxin (PrxVI) and thus contributes to the removal of hydroperoxides, preventing oxidative damage. The effects of prolonged food deprivation on the GSH system are not well described in mammals. To test our hypothesis that GSH biosynthesis increases with fasting in postweaned elephant seals, we measured circulating and muscle GSH content at the early and late phases of the postweaning fast in elephant seals along with the activity/protein content of glutamate-cysteine ligase [GCL; catalytic (GCLc) and modulatory (GCLm) subunits], γ-glutamyl transpeptidase (GGT), glutathione disulphide reductase (GR), glucose-6-phosphate dehydrogenase (G6PDH), GST and PrxVI, as well as plasma changes in γ-glutamyl amino acids, glutamate and glutamine. GSH increased two- to four-fold with fasting along with a 40-50% increase in the content of GCLm and GCLc, a 75% increase in GGT activity, a two- to 2.5-fold increase in GR, G6PDH and GST activities and a 30% increase in PrxVI content. Plasma γ-glutamyl glutamine, γ-glutamyl isoleucine and γ-glutamyl methionine also increased with fasting whereas glutamate and glutamine decreased. Results indicate that GSH biosynthesis increases with fasting and that GSH contributes to counteracting hydroperoxide production, preventing oxidative damage in fasting seals.

Prolonged fasting increases glutathione biosynthesis in postweaned northern elephant seals

PubMed Central

Vázquez-Medina, José Pablo; Zenteno-Savín, Tania; Forman, Henry Jay; Crocker, Daniel E.; Ortiz, Rudy M.

2011-01-01

SUMMARY Northern elephant seals experience prolonged periods of absolute food and water deprivation (fasting) while breeding, molting or weaning. The postweaning fast in elephant seals is characterized by increases in the renin–angiotensin system, expression of the oxidant-producing protein Nox4, and NADPH oxidase activity; however, these increases are not correlated with increased oxidative damage or inflammation. Glutathione (GSH) is a potent reductant and a cofactor for glutathione peroxidases (GPx), glutathione-S transferases (GST) and 1-cys peroxiredoxin (PrxVI) and thus contributes to the removal of hydroperoxides, preventing oxidative damage. The effects of prolonged food deprivation on the GSH system are not well described in mammals. To test our hypothesis that GSH biosynthesis increases with fasting in postweaned elephant seals, we measured circulating and muscle GSH content at the early and late phases of the postweaning fast in elephant seals along with the activity/protein content of glutamate-cysteine ligase [GCL; catalytic (GCLc) and modulatory (GCLm) subunits], γ-glutamyl transpeptidase (GGT), glutathione disulphide reductase (GR), glucose-6-phosphate dehydrogenase (G6PDH), GST and PrxVI, as well as plasma changes in γ-glutamyl amino acids, glutamate and glutamine. GSH increased two- to four-fold with fasting along with a 40–50% increase in the content of GCLm and GCLc, a 75% increase in GGT activity, a two- to 2.5-fold increase in GR, G6PDH and GST activities and a 30% increase in PrxVI content. Plasma γ-glutamyl glutamine, γ-glutamyl isoleucine and γ-glutamyl methionine also increased with fasting whereas glutamate and glutamine decreased. Results indicate that GSH biosynthesis increases with fasting and that GSH contributes to counteracting hydroperoxide production, preventing oxidative damage in fasting seals. PMID:21430206

Glutathione transferases, regulators of cellular metabolism and physiology.

PubMed

Board, Philip G; Menon, Deepthi

2013-05-01

The cytosolic glutathione transferases (GSTs) comprise a super family of proteins that can be categorized into multiple classes with a mixture of highly specific and overlapping functions. The review covers the genetics, structure and function of the human cytosolic GSTs with particular attention to their emerging roles in cellular metabolism. All the catalytically active GSTs contribute to the glutathione conjugation or glutathione dependant-biotransformation of xenobiotics and many catalyze glutathione peroxidase or thiol transferase reactions. GSTs also catalyze glutathione dependent isomerization reactions required for the synthesis of several prostaglandins and steroid hormones and the catabolism of tyrosine. An increasing body of work has implicated several GSTs in the regulation of cell signaling pathways mediated by stress-activated kinases like Jun N-terminal kinase. In addition, some members of the cytosolic GST family have been shown to form ion channels in intracellular membranes and to modulate ryanodine receptor Ca(2+) channels in skeletal and cardiac muscle. In addition to their well established roles in the conjugation and biotransformation of xenobiotics, GSTs have emerged as significant regulators of pathways determining cell proliferation and survival and as regulators of ryanodine receptors that are essential for muscle function. This article is part of a Special Issue entitled Cellular functions of glutathione. Copyright © 2012 Elsevier B.V. All rights reserved.

Regulation of Endothelial Permeability by Glutathione S-Transferase Pi Against Actin Polymerization.

PubMed

Yang, Yang; Yin, Fangyuan; Hang, Qiyun; Dong, Xiaoliang; Chen, Jiao; Li, Ling; Cao, Peng; Yin, Zhimin; Luo, Lan

2018-01-01

Inflammation-induced injury of the endothelial barrier occurs in several pathological conditions, including atherosclerosis, ischemia, and sepsis. Endothelial cytoskeleton rearrangement is an important pathological mechanism by which inflammatory stimulation triggers an increase of vascular endothelial permeability. However, the mechanism maintaining endothelial cell barrier function against inflammatory stress is not fully understood. Glutathione S-transferase pi (GSTpi) exists in various types of cells and protects them against different stresses. In our previous study, GSTpi was found to act as a negative regulator of inflammatory responses. We used a Transwell permeability assay to test the influence of GSTpi and its transferase activity on the increase of endothelial permeability induced by tumor necrosis factor alpha (TNF-α). TNF-α-induced actin remodeling and the influence of GSTpi were observed by using laser confocal microscopy. Western blotting was used to test the influence of GSTpi on TNF-α-activated p38 mitogen-activated protein kinase (MAPK)/MK2/heat shock protein 27 (HSP27). GSTpi reduced TNF-α-induced stress fiber formation and endothelial permeability increase by restraining actin cytoskeleton rearrangement, and this reduction was unrelated to its transferase activity. We found that GSTpi inhibited p38MAPK phosphorylation by directly binding p38 and influenced downstream substrate HSP27-induced actin remodeling. GSTpi inhibited TNF-α-induced actin remodeling, stress fiber formation and endothelial permeability increase by inhibiting the p38MAPK/HSP27 signaling pathway. © 2018 The Author(s). Published by S. Karger AG, Basel.

The Gut Microbiota Mediates the Anti-Seizure Effects of the Ketogenic Diet.

PubMed

Olson, Christine A; Vuong, Helen E; Yano, Jessica M; Liang, Qingxing Y; Nusbaum, David J; Hsiao, Elaine Y

2018-06-14

The ketogenic diet (KD) is used to treat refractory epilepsy, but the mechanisms underlying its neuroprotective effects remain unclear. Here, we show that the gut microbiota is altered by the KD and required for protection against acute electrically induced seizures and spontaneous tonic-clonic seizures in two mouse models. Mice treated with antibiotics or reared germ free are resistant to KD-mediated seizure protection. Enrichment of, and gnotobiotic co-colonization with, KD-associated Akkermansia and Parabacteroides restores seizure protection. Moreover, transplantation of the KD gut microbiota and treatment with Akkermansia and Parabacteroides each confer seizure protection to mice fed a control diet. Alterations in colonic lumenal, serum, and hippocampal metabolomic profiles correlate with seizure protection, including reductions in systemic gamma-glutamylated amino acids and elevated hippocampal GABA/glutamate levels. Bacterial cross-feeding decreases gamma-glutamyltranspeptidase activity, and inhibiting gamma-glutamylation promotes seizure protection in vivo. Overall, this study reveals that the gut microbiota modulates host metabolism and seizure susceptibility in mice. Copyright © 2018 Elsevier Inc. All rights reserved.

21 CFR 862.1030 - Alanine amino transferase (ALT/SGPT) test system.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Alanine amino transferase (ALT/SGPT) test system. 862.1030 Section 862.1030 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry...

21 CFR 862.1100 - Aspartate amino transferase (AST/SGOT) test system.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Aspartate amino transferase (AST/SGOT) test system. 862.1100 Section 862.1100 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry...

21 CFR 862.1030 - Alanine amino transferase (ALT/SGPT) test system.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Alanine amino transferase (ALT/SGPT) test system. 862.1030 Section 862.1030 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry...

21 CFR 862.1100 - Aspartate amino transferase (AST/SGOT) test system.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Aspartate amino transferase (AST/SGOT) test system. 862.1100 Section 862.1100 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry...

21 CFR 862.1100 - Aspartate amino transferase (AST/SGOT) test system.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Aspartate amino transferase (AST/SGOT) test system. 862.1100 Section 862.1100 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry...

21 CFR 862.1030 - Alanine amino transferase (ALT/SGPT) test system.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Alanine amino transferase (ALT/SGPT) test system. 862.1030 Section 862.1030 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry...

21 CFR 862.1100 - Aspartate amino transferase (AST/SGOT) test system.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Aspartate amino transferase (AST/SGOT) test system. 862.1100 Section 862.1100 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry...

21 CFR 862.1100 - Aspartate amino transferase (AST/SGOT) test system.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Aspartate amino transferase (AST/SGOT) test system. 862.1100 Section 862.1100 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry...

21 CFR 862.1030 - Alanine amino transferase (ALT/SGPT) test system.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Alanine amino transferase (ALT/SGPT) test system. 862.1030 Section 862.1030 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry...

21 CFR 862.1030 - Alanine amino transferase (ALT/SGPT) test system.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Alanine amino transferase (ALT/SGPT) test system. 862.1030 Section 862.1030 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry...

A 4'-phosphopantetheinyl transferase mediates non-ribosomal peptide synthetase activation in Aspergillus fumigatus.

PubMed

Neville, Claire; Murphy, Alan; Kavanagh, Kevin; Doyle, Sean

2005-04-01

Aspergillus fumigatus is a significant human pathogen. Non-ribosomal peptide (NRP) synthesis is thought to be responsible for a significant proportion of toxin and siderophore production in the organism. Furthermore, it has been shown that 4'-phosphopantetheinylation is required for the activation of key enzymes involved in non-ribosomal peptide synthesis in other species. Here we report the cloning, recombinant expression and functional characterisation of a 4'-phosphopantetheinyl transferase from A. fumigatus and the identification of an atypical NRP synthetase (Afpes1), spanning 14.3 kb. Phylogenetic analysis has shown that the NRP synthetase exhibits greatest identity to NRP synthetases from Metarhizium anisolpiae (PesA) and Alternaria brassicae (AbrePsy1). Northern hybridisation and RT-PCR analysis have confirmed that both genes are expressed in A. fumigatus. A 120 kDa fragment of the A. fumigatus NRP synthetase, containing a putative thiolation domain, was cloned and expressed in the baculovirus expression system. Detection of a 4'-phosphopantetheinylated peptide (SFSAMK) from this protein, by MALDI-TOF mass spectrometric analysis after coincubation of the 4'-phosphopantetheinyl transferase with the recombinant NRP synthetase fragment and acetyl CoA, confirms that it is competent to play a role in NRP synthetase activation in A. fumigatus. The 4'-phosphopantetheinyl transferase also activates, by 4'-phosphopantetheinylation, recombinant alpha-aminoadipate reductase (Lys2p) from Candida albicans, a key enzyme involved in lysine biosynthesis.

Z{gamma}{gamma}{gamma} {yields} 0 Processes in SANC

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

Bardin, D. Yu., E-mail: bardin@nu.jinr.ru; Kalinovskaya, L. V., E-mail: kalinov@nu.jinr.ru; Uglov, E. D., E-mail: corner@nu.jinr.ru

2013-11-15

We describe the analytic and numerical evaluation of the {gamma}{gamma} {yields} {gamma}Z process cross section and the Z {yields} {gamma}{gamma}{gamma} decay rate within the SANC system multi-channel approach at the one-loop accuracy level with all masses taken into account. The corresponding package for numeric calculations is presented. For checking of the results' correctness we make a comparison with the other independent calculations.

Sneaky Gamma-Rays: Using Gravitational Lensing to Avoid Gamma-Gamma-Absorption

NASA Astrophysics Data System (ADS)

Boettcher, Markus; Barnacka, Anna

2014-08-01

It has recently been suggested that gravitational lensing studies of gamma-ray blazars might be a promising avenue to probe the location of the gamma-ray emitting region in blazars. Motivated by these prospects, we have investigated potential gamma-gamma absorption signatures of intervening lenses in the very-high-energy gamma-ray emission from lensedblazars. We considered intervening galaxies and individual stars within these galaxies. We find that the collective radiation field of galaxies acting as sources of macrolensing are not expected to lead to significant gamma-gamma absorption. Individual stars within intervening galaxies could, in principle, cause a significant opacity to gamma-gamma absorption for VHE gamma-rays if the impact parameter (the distance of closest approach of the gamma-ray to the center of the star) is small enough. However, we find that the curvature of the photon path due to gravitational lensing will cause gamma-ray photons to maintain a sufficiently large distance from such stars to avoid significant gamma-gamma absorption. This re-inforces the prospect of gravitational-lensing studies of gamma-ray blazars without interference due to gamma-gamma absorption due to the lensing objects.

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

PubMed

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

2015-06-01

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

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

PubMed

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

2016-10-01

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

Evaluation of liver function tests in scleroderma patients.

PubMed

Salem, Gehan Ibrahim Abdelrazek; Abdulrahman, Awni Ali

2012-08-01

Systemic sclerosis is a clinically heterogeneous, systemic disorder which affects the connective tissue of the skin, internal organs, and the walls of blood vessels. It is characterized by alterations of the microvasculature, disturbances of the immune system and by massive deposition of collagen and other matrix substances in the connective tissue. This study was done to evaluate the frequency of liver disease in patients with scleroderma and, secondarily, to study the frequency of infection of hepatitis B and C virus in these patients and determine frequency of serum auto-antibodies in this disease. We studied patients with scleroderma, localized or systemic, in the outpatient clinic of rheumatology and dermatology departments, at King Khalid University Hospital. As for a comparison, healthy persons coming to the clinic with the same mean age were considered as control group. Forty patients with the diagnosis of scleroderma included in this work, 35% had elevated gamma-glutamyl-transferase (γ-GT), 30% had elevated alkaline phosphatase (AP) and in 17.5%, the alanine-amino-transferase (ALT) was above the reference values. The ALT had changed to be more in scleroderma patients than in controls. Twenty percent (20%) of the patients tested positive for anti-smooth muscle antibodies (anti-SMA) and only one patient had anti-mitochondrial antibodies (AMA). There was no statistical difference between the two groups regarding antibody testing. Anti-HCV antibodies were observed in one patient, and HBsAg was detected in another scleroderma patient. There was no patient with clinically significant hepatic disease. In this study, although changes in liver enzymes in patients with scleroderma were not uncommon, there was no scleroderma patient with clinical manifestations of liver disease.

Enzymatic synthesis of γ-L-glutamyl-S-allyl-L-cysteine, a naturally occurring organosulfur compound from garlic, by Bacillus licheniformis γ-glutamyltranspeptidase.

PubMed

Chen, Yi-Yu; Lo, Huei-Fen; Wang, Tzu-Fan; Lin, Min-Guan; Lin, Long-Liu; Chi, Meng-Chun

2015-01-01

In the practical application of Bacillus licheniformis γ-glutamyltranspeptidase (BlGGT), we describe a straightforward enzymatic synthesis of γ-L-glutamyl-S-allyl-L-cysteine (GSAC), a naturally occurring organosulfur compound found in garlic, based on a transpeptidation reaction involving glutamine as the γ-glutamyl donor and S-allyl-L-cysteine as the acceptor. With the help of thin layer chromatography technique and computer-assisted image analysis, we performed the quantitative determination of GSAC. The optimum conditions for a biocatalyzed synthesis of GSAC were 200 mM glutamine, 200 mM S-allyl-L-cysteine, 50 mM Tris-HCl buffer (pH 9.0), and BlGGT at a final concentration of 1.0 U/mL. After a 15-h incubation of the reaction mixture at 60 °C, the GSAC yield for the free and immobilized enzymes was 19.3% and 18.3%, respectively. The enzymatic synthesis of GSAC was repeated under optimal conditions at 1-mmol preparative level. The reaction products together with the commercially available GSAC were further subjected to an ESI-MS/MS analysis. A significant signal with m/z of 291.1 and the protonated fragments at m/z of 73.0, 130.1, 145.0, and 162.1 were observed in the positive ESI-MS/MS spectrum, which is consistent with those of the standard compound. These results confirm the successful synthesis of GSAC from glutamine and S-allyl-L-cysteine by BlGGT. Copyright © 2015 Elsevier Inc. All rights reserved.

Polymorphism in the intron 20 of porcine O-linked N-acetylglucosamine transferase

USDA-ARS?s Scientific Manuscript database

Objective: O-linked N-acetylglucosamine (O-GlcNAc) transferase (OGT) catalyzes the addition of O-GlcNAc and GlcNAcylation has extensive crosstalk with phosphorylation to regulate signaling and transcription. Pig OGT is located near the region of chromosome X that affects follicle stimulating hormone...

Genomic organization of plant aminopropyl transferases.

PubMed

Rodríguez-Kessler, Margarita; Delgado-Sánchez, Pablo; Rodríguez-Kessler, Gabriela Theresia; Moriguchi, Takaya; Jiménez-Bremont, Juan Francisco

2010-07-01

Aminopropyl transferases like spermidine synthase (SPDS; EC 2.5.1.16), spermine synthase and thermospermine synthase (SPMS, tSPMS; EC 2.5.1.22) belong to a class of widely distributed enzymes that use decarboxylated S-adenosylmethionine as an aminopropyl donor and putrescine or spermidine as an amino acceptor to form in that order spermidine, spermine or thermospermine. We describe the analysis of plant genomic sequences encoding SPDS, SPMS, tSPMS and PMT (putrescine N-methyltransferase; EC 2.1.1.53). Genome organization (including exon size, gain and loss, as well as intron number, size, loss, retention, placement and phase, and the presence of transposons) of plant aminopropyl transferase genes were compared between the genomic sequences of SPDS, SPMS and tSPMS from Zea mays, Oryza sativa, Malus x domestica, Populus trichocarpa, Arabidopsis thaliana and Physcomitrella patens. In addition, the genomic organization of plant PMT genes, proposed to be derived from SPDS during the evolution of alkaloid metabolism, is illustrated. Herein, a particular conservation and arrangement of exon and intron sequences between plant SPDS, SPMS and PMT genes that clearly differs with that of ACL5 genes, is shown. The possible acquisition of the plant SPMS exon II and, in particular exon XI in the monocot SPMS genes, is a remarkable feature that allows their differentiation from SPDS genes. In accordance with our in silico analysis, functional complementation experiments of the maize ZmSPMS1 enzyme (previously considered to be SPDS) in yeast demonstrated its spermine synthase activity. Another significant aspect is the conservation of intron sequences among SPDS and PMT paralogs. In addition the existence of microsynteny among some SPDS paralogs, especially in P. trichocarpa and A. thaliana, supports duplication events of plant SPDS genes. Based in our analysis, we hypothesize that SPMS genes appeared with the divergence of vascular plants by a processes of gene duplication and the

Characterization of glutathione transferases involved in the pathogenicity of Alternaria brassicicola.

PubMed

Calmes, Benoit; Morel-Rouhier, Mélanie; Bataillé-Simoneau, Nelly; Gelhaye, Eric; Guillemette, Thomas; Simoneau, Philippe

2015-06-18

Glutathione transferases (GSTs) represent an extended family of multifunctional proteins involved in detoxification processes and tolerance to oxidative stress. We thus anticipated that some GSTs could play an essential role in the protection of fungal necrotrophs against plant-derived toxic metabolites and reactive oxygen species that accumulate at the host-pathogen interface during infection. Mining the genome of the necrotrophic Brassica pathogen Alternaria brassicicola for glutathione transferase revealed 23 sequences, 17 of which could be clustered into the main classes previously defined for fungal GSTs and six were 'orphans'. Five isothiocyanate-inducible GSTs from five different classes were more thoroughly investigated. Analysis of their catalytic properties revealed that two GSTs, belonging to the GSTFuA and GTT1 classes, exhibited GSH transferase activity with isothiocyanates (ITC) and peroxidase activity with cumene hydroperoxide, respectively. Mutant deficient for these two GSTs were however neither more susceptible to ITC nor less aggressive than the wild-type parental strain. By contrast mutants deficient for two other GSTs, belonging to the Ure2pB and GSTO classes, were distinguished by their hyper-susceptibility to ITC and low aggressiveness against Brassica oleracea. In particular AbGSTO1 could participate in cell tolerance to ITC due to its glutathione-dependent thioltransferase activity. The fifth ITC-inducible GST belonged to the MAPEG class and although it was not possible to produce the soluble active form of this protein in a bacterial expression system, the corresponding deficient mutant failed to develop normal symptoms on host plant tissues. Among the five ITC-inducible GSTs analyzed in this study, three were found essential for full aggressiveness of A. brassicicola on host plant. This, to our knowledge is the first evidence that GSTs might be essential virulence factors for fungal necrotrophs.

Sorting nexin Snx41 is essential for conidiation and mediates glutathione-based antioxidant defense during invasive growth in Magnaporthe oryzae

PubMed Central

Deng, Yi Zhen; Qu, Ziwei; He, Yunlong; Naqvi, Naweed I.

2012-01-01

The sorting nexins Atg20/Snx42 and Snx41 regulate membrane traffic and endosomal protein sorting and are essential for Cvt and/or pexophagy in yeast. Previously, we showed that macroautophagy is necessary for conidiation in the rice-blast fungus Magnaporthe oryzae. Here, we analyzed the physiological function(s) of selective autophagy in Magnaporthe through targeted deletion of MGG_12832, an ortholog of yeast SNX41 and ATG20/SNX42. Loss of MGG_12832 (hereafter SNX41) abolished conidia formation and pathogenesis in M. oryzae. Snx41-GFP localized as dynamic puncta or short tubules that are partially associated with autophagosomes and/or autophagic vacuoles. PX domain, but not macroautophagy per se, was required for such localization of Snx41-GFP in Magnaporthe. Although not required for nonselective autophagy, Snx41 was essential for pexophagy in Magnaporthe. We identified Oxp1, an ATP-dependent oxoprolinase in the gamma-glutamyl cycle, as a binding partner and potential retrieval target of Snx41-dependent protein sorting. The substrate of Oxp1, 5-oxoproline, could partially restore conidiation in the snx41Δ. Exogenous glutathione, a product of the gamma-glutamyl cycle, significantly restored pathogenicity in the snx41Δ mutant, likely through counteracting the oxidative stress imposed by the host. We propose that the gamma-glutamyl cycle and glutathione biosynthesis are subject to regulation by Snx41-dependent vesicular trafficking, and mediate antioxidant defense crucial for in planta growth and pathogenic differentiation of Magnaporthe at the onset of blast disease in rice. PMID:22561104

Global deletion of glutathione S-Transferase A4 exacerbates developmental nonalcoholic steatohepatitis

USDA-ARS?s Scientific Manuscript database

We established a mouse model of developmental nonalcoholic steatohepatitis (NASH) by feeding a high polyunsaturated fat liquid diet to female glutathione-S-transferase 4-4 (Gsta4-/-)/peroxisome proliferator activated receptor a (Ppara-/-) double knockout 129/SvJ mice for 12 weeks from weaning. We us...

Dietary vitamin K and therapeutic warfarin alter susceptibility to vascular calcification in experimental chronic kidney disease

USDA-ARS?s Scientific Manuscript database

The leading cause of death in patients with chronic kidney disease (CKD) is cardiovascular disease (CVD), with vascular calcification (VC) being a key modifier of disease progression. A local regulator of vascular calcification is vitamin K. This gamma-glutamyl carboxylase substrate is an essential ...

The Z {yields} cc-bar {yields} {gamma}{gamma}*, Z {yields} bb-bar {yields} {gamma}{gamma}* triangle diagrams and the Z {yields} {gamma}{psi}, Z {yields} {gamma}Y decays

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

Achasov, N. N., E-mail: achasov@math.nsc.ru

2011-03-15

The approach to the Z {yields} {gamma}{psi} and Z {yields} {gamma}Y decay study is presented in detail, based on the sum rules for the Z {yields} cc-bar {yields} {gamma}{gamma}* and Z {yields} bb-bar {yields} {gamma}{gamma}* amplitudes and their derivatives. The branching ratios of the Z {yields} {gamma}{psi} and Z {yields} {gamma}Y decays are calculated for different hypotheses on saturation of the sum rules. The lower bounds of {Sigma}{sub {psi}} BR(Z {yields} {gamma}{psi}) = 1.95 Multiplication-Sign 10{sup -7} and {Sigma}{sub {upsilon}} BR(Z {yields} {gamma}Y) = 7.23 Multiplication-Sign 10{sup -7} are found. Deviations from the lower bounds are discussed, including the possibilitymore » of BR(Z {yields} {gamma}J/{psi}(1S)) {approx} BR(Z {yields} {gamma}Y(1S)) {approx} 10{sup -6}, that could be probably measured in LHC. The angular distributions in the Z {yields} {gamma}{psi} and Z {yields} {gamma}Y decays are also calculated.« less

Glutathione S-transferase P1 (GSTP1) directly influences platinum drug chemosensitivity in ovarian tumour cell lines.

PubMed

Sawers, L; Ferguson, M J; Ihrig, B R; Young, H C; Chakravarty, P; Wolf, C R; Smith, G

2014-09-09

Chemotherapy response in ovarian cancer patients is frequently compromised by drug resistance, possibly due to altered drug metabolism. Platinum drugs are metabolised by glutathione S-transferase P1 (GSTP1), which is abundantly, but variably expressed in ovarian tumours. We have created novel ovarian tumour cell line models to investigate the extent to which differential GSTP1 expression influences chemosensitivity. Glutathione S-transferase P1 was stably deleted in A2780 and expression significantly reduced in cisplatin-resistant A2780DPP cells using Mission shRNA constructs, and MTT assays used to compare chemosensitivity to chemotherapy drugs used to treat ovarian cancer. Differentially expressed genes in GSTP1 knockdown cells were identified by Illumina HT-12 expression arrays and qRT-PCR analysis, and altered pathways predicted by MetaCore (GeneGo) analysis. Cell cycle changes were assessed by FACS analysis of PI-labelled cells and invasion and migration compared in quantitative Boyden chamber-based assays. Glutathione S-transferase P1 knockdown selectively influenced cisplatin and carboplatin chemosensitivity (2.3- and 4.83-fold change in IC50, respectively). Cell cycle progression was unaffected, but cell invasion and migration was significantly reduced. We identified several novel GSTP1 target genes and candidate platinum chemotherapy response biomarkers. Glutathione S-transferase P1 has an important role in cisplatin and carboplatin metabolism in ovarian cancer cells. Inter-tumour differences in GSTP1 expression may therefore influence response to platinum-based chemotherapy in ovarian cancer patients.

Relationship among blood indicators of lipomobilization and hepatic function during early lactation in high-yielding dairy cows

PubMed Central

Muiño, Rodrigo; Pereira, Víctor; Campos, Rómulo; Benedito, José Luis

2011-01-01

Blood indicators are used as a tool to diagnose metabolic disorders. The present work was conducted to study the relationships among blood indicators of lipomobilization and hepatic function in high-yielding dairy cows. Two groups of Holstein cows were studied: 27 early lactation cows and 14 mid lactation cows from four different herds with similar husbandry characteristics in Galicia, Spain. Blood samples were obtained to measure beta-hydroxybutyrate (BHB), non-esterified fatty acids (NEFA), triglycerides (TG), and the activity of aspartate transaminase (AST) and gamma-glutamyl transferase. Cows in early lactation had higher levels of BHB and NEFA than mid lactation cows. High lipomobilization (NEFA > 400 µmol/L) was detected in 67% and 7% of early lactation and mid lactation cows, respectively, while subclinical ketosis (BHB > 1.2 mmol/L) was detected in 41% and 28% of the early lactation and lactation cows, respectively. TG concentrations were low in all cows suffering subclinical ketosis and in 61% of the cows with high lipomobilization. During early lactation, 30% of cows suffered hepatic lipidosis as detected by levels of AST. Compromised hepatic function was observed in early lactation cows as shown by lower concentrations of glucose, total protein, and urea. PMID:21897097

Excessive drinking--brief intervention by a primary health care nurse. A randomized controlled trial.

PubMed

Tomson, Y; Romelsjö, A; Aberg, H

1998-09-01

To evaluate the effect of a nurse-conducted intervention on excessive drinkers. Randomized, controlled trial. Vårby Health Centre, Stockholm. The intervention group visited a nurse three times during a 12-month period. The controls met once with a general practitioner (GP). Patients were recruited at a health screening on the basis of a raised gamma-glutamyl transferase (GGT). Of 2338 subjects, aged 25-54 years, 222 had a screening GGT of > or = 0.9 mukat/l. 100 were randomized to the treatment and 122 to the control group. GGT, self-reported alcohol consumption (g/week), sickness allowance and use of health care. After 2 years a reduction of GGT from 1.52 to 1.21 mukat/l (p = 0.02) had occurred in the treatment group. The controls increased their mean level of GGT from 1.75 to 2.16 mukat/l. Mean weekly alcohol consumption in the intervention group was reduced from 337 to 228 g/week (p = 0.02). The controls did not quantify their alcohol consumption initially, but reported a reduced weekly consumption at follow-up. The intervention had an impact on GGT and self-reported consumption. The controls also reported decreased consumption possibly because their appointment with the GP functioned as a very brief intervention.

Hepatoprotective Effects of Chinese Medicine Herbs Decoction on Liver Cirrhosis in Rats

PubMed Central

Lim, Tong-Hye; Nor-Amdan, Nur-Asyura

2017-01-01

Hepatoprotective and curative activities of aqueous extract of decoction containing 10 Chinese medicinal herbs (HPE-XA-08) were evaluated in Sprague–Dawley albino rats with liver damage induced by thioacetamide (TAA). These activities were assessed by investigating the liver enzymes level and also histopathology investigation. Increases in alkaline phosphatase (ALP) and gamma-glutamyl transferase (GGT) levels were observed in rats with cirrhotic liver. No significant alterations of the liver enzymes were observed following treatment with HPE-XA-08. Histopathology examination of rats treated with HPE-XA-08 at 250 mg/kg body weight, however, exhibited moderate liver protective effects. Reduced extracellular matrix (ECM) proteins within the hepatocytes were noted in comparison to the cirrhotic liver. The curative effects of HPE-XA-08 were observed with marked decrease in the level of ALP (more than 3x) and level of GGT (more than 2x) in cirrhotic rat treated with 600 mg/kg body weight HPE-XA-08 in comparison to cirrhotic rat treated with just water diluent. Reversion of cirrhotic liver to normal liver condition in rats treated with HPE-XA-08 was observed. Results from the present study suggest that HPE-XA-08 treatment assisted in the protection from liver cirrhosis and improved the recovery of cirrhotic liver. PMID:28280515

Body Mass Index and C-Reactive Protein in the Healthy Korean Aged Men

PubMed Central

Lee, Sang Won; Choi, Hyun Rim; Kim, Byung Sung; Park, Hye Soon; Yukawa, Michi

2006-01-01

The purpose of this study was to determine the relationship between plasma C-reactive protein (CRP) and body mass index (BMI) in elderly Korean men. A review of routine health examination records were done. Out of 671 eligible elderly men, who had their routine health examination in 2001 at a Health Promotion Center of a university hospital, 367 subjects were included after excluding inflammatory conditions. Subgroup analyses were performed on those who did not smoke and exercised regularly. Body composition, blood pressure, blood samples and radiologic examinations including chest radiography and abdominal ultrasound were obtained from each subject. Age, BMI, current smoking, regular exercise, WBC count, HDL-cholesterol, gamma glutamyl transferase were independently associated with logCRP. BMI subgroups according to the Asia-Pacific guideline did not show any difference in CRP level from each other by ANCOVA (p>0.05). However, BMI groups subdivided according to our criteria showed an association with CRP; the CRP level was lowest in the group of BMI between 18.5-19.4 and showed significant difference from BMI group of the highest BMI group (≥29.0). Since elevated CRP levels are associated with higher risk for cardiovascular disease, lower BMI (18.5-19.4) levels may be advised for healthy elderly men in Korea. PMID:17043411

d-limonene ameliorates diabetes and its complications in streptozotocin-induced diabetic rats.

PubMed

Bacanlı, Merve; Anlar, Hatice Gül; Aydın, Sevtap; Çal, Tuğbagül; Arı, Nuray; Ündeğer Bucurgat, Ülkü; Başaran, A Ahmet; Başaran, Nurşen

2017-12-01

It is known that diabetes causes some complications including alterations in lipid profile, hepatic enzyme levels but also it causes oxidative stress. Limonene, a major component of Citrus oils, has important health beneficial effects in lowering the level of oxidative stress due to its antioxidant activity. The aim of this study was to investigate the effects of D-limonene on streptozotocin (STZ)-induced diabetes in Wistar albino rats. For this purpose, DNA damage was evaluated by alkaline comet assay. Changes in the activities of catalase (CAT), superoxide dismutase (SOD), glutathione reductase (GR) and glutathione peroxidase (GSHPx) and the levels of 8-hydroxy-2'-deoxyguanosine (8-OHdG), total glutathione (GSH), malondialdehyde (MDA), insulin, total bilirubin and BCA protein, alanine aminotransferase (ALT), aspartate aminotransferase (AST) and gamma-glutamyl transferase (GGT), high density lipoprotein (HDL), low density lipoprotein (LDL), total cholesterol and triglyceride were also evaluated. D-limonene treatment was found to significantly decrease DNA damage, GR enzyme activities and MDA levels and significantly increase GSH levels and CAT, SOD and GSH-Px enzyme activities and altered lipid and liver enzyme parameters in diabetic rats. According to our results, it seems that D-limonene might have a role in the prevention of the complication of diabetes in rats. Copyright © 2017 Elsevier Ltd. All rights reserved.

Dietary antioxidant and anti-inflammatory intake modifies the effect of cadmium exposure on markers of systemic inflammation and oxidative stress.

PubMed

Colacino, Justin A; Arthur, Anna E; Ferguson, Kelly K; Rozek, Laura S

2014-05-01

Chronic cadmium exposure may cause disease through induction of systemic oxidative stress and inflammation. Factors that mitigate cadmium toxicity and could serve as interventions in exposed populations have not been well characterized. We used data from the 2003-2010 National Health and Nutrition Examination Survey to quantify diet׳s role in modifying associations between cadmium exposure and oxidative stress and inflammation. We created a composite antioxidant and anti-inflammatory diet score (ADS) by ranking participants by quintile of intake across a panel of 19 nutrients. We identified associations and effect modification between ADS, urinary cadmium, and markers of oxidative stress and inflammation by multiple linear regression. An interquartile range increase in urinary cadmium was associated with a 47.5%, 8.8%, and 3.7% increase in C-reactive protein (CRP), gamma glutamyl transferase (GGT), and alkaline phosphatase (ALP), respectively. An interquartile range increase in ADS was associated with an 7.4%, 3.3%, 5.2%, and 2.5% decrease in CRP, GGT, ALP, and total white blood cell count respectively, and a 3.0% increase in serum bilirubin. ADS significantly attenuated the association between cadmium exposure, CRP and ALP. Dietary interventions may provide a route to reduce the impact of cadmium toxicity on the population level. Copyright © 2014 Elsevier Inc. All rights reserved.

Dietary antioxidant and anti-inflammatory intake modifies the effect of cadmium exposure on markers of systemic inflammation and oxidative stress

PubMed Central

Colacino, Justin A.; Arthur, Anna E.; Ferguson, Kelly K.; Rozek, Laura S.

2014-01-01

Chronic cadmium exposure may cause disease through induction of systemic oxidative stress and inflammation. Factors that mitigate cadmium toxicity and could serve as interventions in exposed populations have not been well characterized. We used data from the 2003–2010 National Health and Nutrition Examination Survey to quantify diet’s role in modifying associations between cadmium exposure and oxidative stress and inflammation. We created a composite antioxidant and anti-inflammatory diet score (ADS) by ranking participants by quintile of intake across a panel of 19 nutrients. We identified associations and effect modification between ADS, urinary cadmium, and markers of oxidative stress and inflammation by multiple linear regression. An interquartile range increase in urinary cadmium was associated with a 47.5%, 8.8%, and 3.7% increase in C-reactive protein (CRP), gamma glutamyl transferase (GGT), and alkaline phosphatase (ALP), respectively. An interquartile range increase in ADS was associated with an 7.4%, 3.3%, 5.2%, and 2.5% decrease in CRP, GGT, ALP, and total white blood cell count respectively, and a 3.0% increase in serum bilirubin. ADS significantly attenuated the association between cadmium exposure, CRP and ALP. Dietary interventions may provide a route to reduce the impact of cadmium toxicity on the population level. PMID:24607659

Comparison of covered and uncovered self-expandable stents in the treatment of malignant biliary obstruction.

PubMed

Flores Carmona, Diana Yamel; Alonso Lárraga, Juan Octavio; Hernández Guerrero, Angélica; Ramírez Solís, Mauro Eduardo

2016-05-01

Drainage with metallic stents is the treatment of choice in malignant obstructive jaundice. Technical and clinical success with metallic stents is obtained in over 90% and 80% of cases, respectively. There are self-expandable metallic stents designed to increase permeability. The aim of this study was to describe the results obtained with totally covered self-expandable and uncovered self-expandable metallic stents in the palliative treatment of malignant biliary obstruction. Sixty eight patients with malignant obstructive jaundice secondary to pancreatobiliary or metastatic disease not amenable to surgery were retrospectively included. Two groups were created: group A (covered self-expandable metallic stents) (n = 22) and group B (uncovered self-expandable metallic stents) (n = 46). Serum total bilirubin, direct bilirubin, alkaline phosphatase and gamma glutamyl transferase levels decreased in both groups and no statistically significant difference was detected (p = 0.800, p = 0.190, p = 0.743, p = 0.521). Migration was greater with covered stents but it was not statistically significant either (p = 0.101). Obstruction was greater in the group with uncovered stents but it was not statistically significant either (p = 0.476). There are no differences when using covered self-expandable stents or uncovered self-expandable stents in terms of technical and clinical success or complications in the palliative treatment of malignant obstructive jaundice.

Quality specifications for the extra-analytical phase of laboratory testing: Reference intervals and decision limits.

PubMed

Ceriotti, Ferruccio

2017-07-01

Reference intervals and decision limits are a critical part of the clinical laboratory report. The evaluation of their correct use represents a tool to verify the post analytical quality. Four elements are identified as indicators. 1. The use of decision limits for lipids and glycated hemoglobin. 2. The use, whenever possible, of common reference values. 3. The presence of gender-related reference intervals for at least the following common serum measurands (besides obviously the fertility relate hormones): alkaline phosphatase (ALP), alanine aminotransferase (ALT), creatine kinase (CK), creatinine, gamma-glutamyl transferase (GGT), IgM, ferritin, iron, transferrin, urate, red blood cells (RBC), hemoglobin (Hb) and hematocrit (Hct). 4. The presence of age-related reference intervals. The problem of specific reference intervals for elderly people is discussed, but their use is not recommended; on the contrary it is necessary the presence of pediatric age-related reference intervals at least for the following common serum measurands: ALP, amylase, creatinine, inorganic phosphate, lactate dehydrogenase, aspartate aminotransferase, urate, insulin like growth factor 1, white blood cells, RBC, Hb, Hct, alfa-fetoprotein and fertility related hormones. The lack of such reference intervals may imply significant risks for the patients. Copyright © 2017 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

Biochemical and histological responses of Rattus novergicus (Wistar) infected by Echinostoma paraensei (Trematoda: Echinostomatidae).

PubMed

Garcia, Juberlan S; Hooper, Cleber S; Simões, Raquel O; Dos Santos, Marcos Antônio J; Maldonado, Arnaldo; Pinheiro, Jairo

2011-05-31

Tests were performed to evaluate the biochemical alterations in Rattus norvegicus after infection by the intestinal trematode Echinostoma paraensei. The rodents received 150 metacercariae each, serum samples were collected and the parasite load was quantified weekly until the fifth week of infection. The levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALKP), gamma-glutamyl transferase (GGT), bilirubin, glucose, total proteins and fractions and hepatic glycogen were determined. All the animals exposed to the metacercariae were infected in the first week and worms were recovered up to the third week after infection. The levels of AST, ALT, GGT, bilirubin and globulin rose in the first and/or second week and declined thereafter to levels near those of the control group. In contrast, the level of total proteins in the plasma fell significantly in the first week while the ALKP activity went down only in the fourth and fifth weeks in relation to the control group. There was no significant difference in the levels of albumin, glycogen and glucose. Infection by E. paraensei in R. norvegicus causes changes in the hepatic function, possibly resulting from the cholestasis produced by the partial obstruction of the bile duct by the helminths. Copyright © 2011 Elsevier B.V. All rights reserved.

Hematology, plasma biochemistry, and tissue enzyme activities of invasive red lionfish captured off North Carolina, USA.

PubMed

Anderson, E T; Stoskopf, M K; Morris, J A; Clarke, E O; Harms, C A

2010-12-01

The red lionfish Pterois volitans is important not only in the aquarium trade but also as an invasive species in the western Atlantic. Introduced to waters off the southeastern coast of the United States, red lionfish have rapidly spread along much of the East Coast and throughout Bermuda, the Bahamas, and much of the Caribbean. Hematology and plasma biochemistry were evaluated in red lionfish captured from the offshore waters of North Carolina to establish baseline parameters for individual and population health assessment. Blood smears were evaluated for total and differential white blood cell counts, and routine clinical biochemical profiles were performed on plasma samples. To improve the interpretive value of routine plasma biochemistry profiles, tissue enzyme activities (alkaline phosphatase [ALP], alanine aminotransferase [ALT], aspartate aminotransferase [AST], gamma-glutamyl transferase [GGT], lactate dehydrogenase [LD], and creatine kinase [CK]) were analyzed from liver, kidney, skeletal muscle, gastrointestinal tract, and heart tissues from five fish. The hematological and plasma biochemical values were similar to those of other marine teleosts except that the estimated white blood cell counts were much lower than those routinely found in many species. The tissue enzyme activity findings suggest that plasma LD, CK, and AST offer clinical relevance in the assessment of red lionfish.

Mortality of captive whooping cranes caused by eastern equine encephalitis virus.

PubMed

Dein, F J; Carpenter, J W; Clark, G G; Montali, R J; Crabbs, C L; Tsai, T F; Docherty, D E

1986-11-01

Of 39 captive whooping cranes (Grus americana), 7 died during a 7-week period (Sept 17 through Nov 4, 1984) at the Patuxent Wildlife Research Center, Laurel, Md. Before their deaths, 4 cranes did not develop clinical signs, whereas the other 3 cranes were lethargic and ataxic, with high aspartate transaminase, gamma-glutamyl transferase, and lactic acid dehydrogenase activities, and high uric acid concentrations. Necropsies indicated that the birds had ascites, intestinal mucosal discoloration, fat depletion, hepatomegaly, splenomegaly, and visceral gout. Microscopically, extensive necrosis and inflammation were seen in many visceral organs; the CNS was not affected. Eastern equine encephalitis (EEE) virus was isolated from specimens of the livers, kidneys, lungs, brains, and intestines of 4 of the 7 birds that died, and EEE virus-neutralizing antibody was detected in 14 (44%) of the 32 surviving birds. Other infectious or toxic agents were not found. Morbidity or mortality was not detected in 240 sandhill cranes (Grus canadensis) interspersed among the whooping cranes; however, 13 of the 32 sandhill cranes evaluated had EEE virus-neutralizing antibody. Of the 41 wild birds evaluated in the area, 3 (4%) had EEE virus-neutralizing antibody. Immature Culiseta melanura (the most probable mosquito vector) were found in scattered foci 5 km from the research center.

Clinical efficacy and safety of imepitoin in comparison with phenobarbital for the control of idiopathic epilepsy in dogs.

PubMed

Tipold, A; Keefe, T J; Löscher, W; Rundfeldt, C; de Vries, F

2015-04-01

The anticonvulsant activity and safety of imepitoin, a novel antiepileptic drug licensed in the European Union, were evaluated in a multicentre field efficacy study as well as in a safety study under laboratory conditions. Efficacy of imepitoin was compared with phenobarbital in 226 client-owned dogs in a blinded parallel group design. The administration of imepitoin twice daily in incremental doses of 10, 20 or 30 mg/kg demonstrated comparable efficacy to phenobarbital in controlling seizures in dogs. The frequency of adverse events including somnolence/sedation, polydipsia and increased appetite was significantly higher in the phenobarbital group. In phenobarbital-treated dogs, significantly increased levels of alkaline phosphatase, gamma-glutamyl-transferase and other liver enzymes occurred, while no such effect was observed in the imepitoin group. In a safety study under laboratory conditions, healthy beagle dogs were administered 0, 30, 90 or 150 mg/kg imepitoin twice daily for 26 weeks. A complete safety evaluation including histopathology was included in the study. A no-observed-adverse-event level of 90 mg/kg twice daily was determined. These results indicate that imepitoin is a potent and safe antiepileptic drug for dogs. © 2014 The Authors. Journal of Veterinary Pharmacology and Therapeutics Published by John Wiley & Sons Ltd.

Effect of juice and fermented vinegar from Hovenia dulcis peduncles on chronically alcohol-induced liver damage in mice.

PubMed

Xiang, Jinle; Zhu, Wenxue; Li, Zhixi; Ling, Shengbao

2012-06-01

The protective effects of juice and fermented vinegar from Hovenia dulcis peduncles on chronically ethanol-induced biochemical changes in male mice were investigated. Administration of ethanol (50%, v/v, 10 mL kg⁻¹) to mice for 6 weeks induced liver damage with a significant increase (P < 0.01) of the liver index, aspartate transaminase (AST), alanine transaminase (ALT), gamma glutamyl transferase (γ-GT) in the serum and the hepatic lipid peroxidation (LPO) level. In contrast, administration of juice or fermented vinegar from Hovenia dulcis peduncles (10 mL kg⁻¹ bw) along with alcohol significantly (P < 0.05) decreased the activities of the enzymes (AST, ALT and γ-GT), liver index, concentrations of triglyceride (TG) and total cholesterol (TCH) in the serum and the hepatic TG and LPO levels. Mice treated with juice or fermented vinegar from Hovenia dulcis peduncles showed better profiles of the antioxidant systems with relatively higher glutathione (GSH) content, total superoxide dismutase (T-SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) activities. All these results were accompanied by histological observations in liver. The results demonstrate that both of the juice and fermented vinegar from Hovenia dulcis peduncles have beneficial effects in reducing the adverse effect of alcohol.

Mortality of captive whooping cranes caused by eastern equine encephalitis virus

USGS Publications Warehouse

Dein, F.J.; Carpenter, J.W.; Clark, G.G.; Montali, R.J.; Crabbs, C.L.; Tsai, T.F.; Docherty, D.E.

1986-01-01

Of 39 captive whooping cranes (Grus americana), 7 died during a 7-week period (Sept 17 through Nov 4, 1984) at the Patuxent Wildlife Research Center, Laurel, Md. Before their deaths, 4 cranes did not develop clinical signs, whereas the other 3 cranes were lethargic and ataxic, with high aspartate transaminase, gamma-glutamyl transferase, and lactic acid dehydrogenase activities, and high uric acid concentrations. Necropsies indicated that the birds had ascites, intestinal mucosal discoloration, fat depletion, hepatomegaly, splenomegaly, and visceral gout. Microscopically, extensive necrosis and inflammation were seen in many visceral organs; the CNS was not affected. Eastern equine encephalitis (EEE) virus was isolated from specimens of the livers, kidneys, lungs, brains, and intestines of 4 of the 7 birds that died, and EEE virus-neutralizing antibody was detected in 14 (44%) of the 32 surviving birds. Other infectious or toxic agents were not found. Morbidity or mortality was not detected in 240 sandhill cranes (Grus canadensis) interspersed among the whooping cranes; however, 13 of the 32 sandhill cranes evaluated had EEE virus-neutralizing antibody. Of the 41 wild birds evaluated in the area, 3 (4%) had EEE virus-neutralizing antibody. Immature Culiseta melanura (the most probable mosquito vector) were found in scattered foci 5 km from the research center.

mTORC1 inhibitors rapamycin and metformin affect cardiovascular markers differentially in ZDF rats.

PubMed

Nistala, Ravi; Raja, Ahmad; Pulakat, Lakshmi

2017-03-01

Mammalian target for rapamycin complex 1 (mTORC1) is a common target for the action of immunosuppressant macrolide rapamycin and glucose-lowering metformin. Inhibition of mTORC1 can exert both beneficial and detrimental effects in different pathologies. Here, we investigated the differential effects of rapamycin (1.2 mg/kg per day delivered subcutaneously for 6 weeks) and metformin (300 mg/kg per day delivered orally for 11 weeks) treatments on male Zucker diabetic fatty (ZDF) rats that mimic the cardiorenal pathology of type 2 diabetic patients and progress to insulin insufficiency. Rapamycin and metformin improved proteinuria, and rapamycin also reduced urinary gamma glutamyl transferase (GGT) indicating improvement of tubular health. Metformin reduced food and water intake, and urinary sodium and potassium, whereas rapamycin increased urinary sodium. Metformin reduced plasma alkaline phosphatase, but induced transaminitis as evidenced by significant increases in plasma AST and ALT. Metformin also induced hyperinsulinemia, but did not suppress fasting plasma glucose after ZDF rats reached 17 weeks of age, and worsened lipid profile. Rapamycin also induced mild transaminitis. Additionally, both rapamycin and metformin increased plasma uric acid and creatinine, biomarkers for cardiovascular and renal disease. These observations define how rapamycin and metformin differentially modulate metabolic profiles that regulate cardiorenal pathology in conditions of severe type 2 diabetes.

Protective Effect of Cymbopogon citratus Essential Oil in Experimental Model of Acetaminophen-Induced Liver Injury.

PubMed

Uchida, Nancy Sayuri; Silva-Filho, Saulo Euclides; Aguiar, Rafael Pazinatto; Wiirzler, Luiz Alexandre Marques; Cardia, Gabriel Fernando Esteves; Cavalcante, Heitor Augusto Otaviano; Silva-Comar, Francielli Maria de Souza; Becker, Tânia Cristina Alexandrino; Silva, Expedito Leite; Bersani-Amado, Ciomar Aparecida; Cuman, Roberto Kenji Nakamura

2017-01-01

To investigate the hepatoprotective effect of Cymbopogon citratus or lemongrass essential oil (LGO), it was used in an animal model of acute liver injury induced by acetaminophen (APAP). Swiss mice were pretreated with LGO (125, 250 and 500[Formula: see text]mg/kg) and SLM (standard drug, 200[Formula: see text]mg/kg) for a duration of seven days, followed by the induction of hepatotoxicity of APAP (single dose, 250[Formula: see text]mg/kg). The liver function markers alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP) and gamma-glutamyl transferase were determined to evaluate the hepatoprotective effects of the LGO. The livers were used to determine myeloperoxidase (MPO) activity, nitric oxide (NO) production and histological analysis. The effect of LGO on leukocyte migration was evaluated in vitro. Anti-oxidant activity was performed by assessing the free radical 2,2-diphenyl-1-picrylhydrazyl (DPPH) in vitro. LGO pretreatment decreased significantly the levels of ALT, AST and ALP compared with APAP group. MPO activity and NO production were decreased. The histopathological analysis showed an improved of hepatic lesions in mice after LGO pretreatment. LGO inhibited neutrophil migration and exhibited anti-oxidant activity. Our results suggest that LGO has protective activity against liver toxicity induced by paracetamol.

[The role of expired air moisture condensate in assessment of pulmonary inflammation in patients with chronic obstructive pulmonary disease].

PubMed

Dotsenko, E K; Goncharova, V A; Kuzubova, N A; Kamenova, M Iu; Egorova, N V

2008-01-01

To study biochemical composition of expired air condensate (EAC) in patients with chronic obstructive pulmonary disease (COPD) in relation to a phase and severity of the disease and its treatment. EAC was investigated in 18 COPD patients and 9 healthy subjects. Basic broncholytic therapy with ipratropium bromide was combined with beclomethasone and fenspiride in 11 and 7 patients, respectively. The condensate was lyophilised, the residue was solved and analysed on the biochemical analyzer Casis (Beringer Manheim, Rosch). EAC was examined for albumin, C-reactive protein, glucose, cholesterol, triglycerides, urea, uric acid, alkaline phosphatase (AP), lactate dehydrogenase, gamma-glutamyl transferase, total calcium, magnesium. Compared to healthy subjects, COPD patients' EAC contains significantly higher levels of albumin, C-reactive protein, calcium, bilirubin and more active AP. Quantitative composition of EAC depends on COPD phase and severity. A negative correlation exists between FEV+AEA-1 and albumin concentration, FEV+AEA-1 and CRP concentration. The anti-inflammatory therapy decreases EAC content of both protein and lipid metabolism products, enzyme activity reflecting attenuation of oxidant and inflammatory processes, stabilization of cell membranes in the respiratory zone. EAC composition reflects metabolic processes in the lungs and can be used for assessment of airway affection, activity of the inflammatory process and COPD treatment efficacy.

Metabolic effects of polycystic ovary syndrome in adolescents

PubMed Central

Han, Yejin; Lee, Hye-Jin; Oh, Jee-Young; Sung, Yeon-Ah

2015-01-01

Purpose Polycystic ovary syndrome (PCOS) is characterized by hyperandrogenic anovulation in women of reproductive age. We investigated the metabolic effects of lean and overweight adolescents with PCOS. Methods Anthropometric measurements and biochemical parameters were evaluated in 49 adolescents with PCOS and 40 age- and body mass index (BMI)-matched controls. We further divided both PCOS and control groups into those having BMI within the normal range of less than 85th percentile and those being overweight and obese with a BMI greater than 85th percentile. Results Hemoglobin, gamma-glutamyl transferase (r-GT), total cholesterol, low-density lipoprotein-cholesterol and 2-hour postglucose load plasma insulin levels were significantly elevated in the lean PCOS group than in the lean control group. In the overweight/obese PCOS group, hemoglobin and r-GT levels were significantly elevated than in the overweight/obese control group. In the normal weight group, none of the subjects had metabolic syndrome according to the Adult Treatment Panel III criteria, but the incidence of metabolic syndrome in the overweight/obese PCOS group was 8.3% and that in the overweight/obese control group was 6.7%. Conclusion PCOS in adolescents causes metabolic abnormalities, underscoring the importance of early diagnosis of PCOS in oligomenorrheic adolescents. PMID:26512349

Molecular cloning, heterologous expression and functional characterization of gamma tocopherol methyl transferase (γ-TMT) from Glycine max.

PubMed

Tewari, Kalpana; Dahuja, Anil; Sachdev, Archana; Kumar, Vaibhav; Ali, Kishwar; Kumar, Amresh; Kumari, Sweta

2017-12-01

γ-Tocopherol methyltransferase (γ-TMT) (EC 2.1.1.95) is the last enzyme in the tocopherol biosynthetic pathway and it catalyzes the conversion of γ-tocopherol into α-tocopherol, the nutritionally significant and most bioactive form of vitamin E. Although the γ-TMT gene has been successfully overexpressed in many crops to enhance their α-tocopherol content but still only few attempts have been made to uncover its structural, functional and regulation aspects at protein level. In this study, we have cloned the complete 909bp coding sequence of Glycine max γ-TMT (Gm γ-TMT) gene that encodes the corresponding protein comprising of 302 amino acid residues. The deduced Gm γ-TMT protein showed 74-87% sequence identity with other characterized plant γ-TMTs. Gm γ-TMT belongs to Class I Methyl Transferases that have a Rossmann-like fold which consists of a seven-stranded β sheet joined by α helices. Heterologous expression of Gm γ-TMT in pET29a expression vector under the control of bacteriophage T7 promoter produced a 37.9 kDa recombinant Gm γ-TMT protein with histidine hexamer tag at its C-terminus. The expression of recombinant Gm γ-TMT protein was confirmed by western blotting using anti-His antibody. The recombinant protein was purified by Ni 2+ -NTA column chromatography. The purified protein showed SAM dependent methyltransferase activity. The α-tocopherol produced in the in-vitro reaction catalyzed by the purified enzyme was detected using reverse phase HPLC. This study has laid the foundation to unveil the biochemical understanding of Gm γ-TMT enzyme which can be further explored by studying its kinetic behaviour, substrate specificity and its interaction with other biomolecules. Copyright © 2017 Elsevier Inc. All rights reserved.

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

PubMed

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

1994-09-01

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

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

PubMed

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

1995-10-12

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

Meta-analysis of the relationship of mycotoxins with biochemical and hematological parameters in broilers.

PubMed

Andretta, I; Kipper, M; Lehnen, C R; Lovatto, P A

2012-02-01

A meta-analysis was carried out to study the association of mycotoxins with hematological and biochemical profiles in broilers. Ninety-eight articles published between 1980 and 2009 were used in the database, totaling 37,371 broilers. The information was selected from the Materials and Methods and Results sections in the selected articles and then tabulated in a database. Meta-analysis followed 3 sequential analyses: graphic, correlation, and variance-covariance. Mycotoxins reduced (P < 0.05) the hematocrit (-5%), hemoglobin (-15%), leukocytes (-25%), heterophils (-2%), lymphocytes (-2%), uric acid (-31%), creatine kinase (-27%), creatinine (-23%), triglycerides (-39%), albumin (-17%), globulin (-1%), total cholesterol (-14%), calcium (-5%), and inorganic phosphorus (-12%). Mycotoxins also altered (P < 0.05) the concentrations of alkaline phosphatase, alanine aminotransferase, and aspartate aminotransferase. A quadratic effect was observed on the relationship between the concentration of aflatoxin in diets and the serum concentration of alkaline phosphatase, γ-glutamyl transferase, alanine aminotransferase, and aspartate aminotransferase. The total protein concentration in blood was 18% lower (P < 0.05) in broilers challenged by aflatoxins compared with that of the unchallenged ones. The inclusion of antimycotoxin additives in diets with aflatoxins altered (P < 0.05) some variables (uric acid, creatinine, alkaline phosphatase, alanine aminotransferase, aspartate aminotransferase, and γ-glutamyl transferase) in relation to the group that received diets with the mycotoxin and without the additive. The meta-analysis performed in this study allowed us to address and quantify systematically the relationship of mycotoxins with alterations in hematologic and biochemical profiles in broilers.

Interferon-gamma interferes with transforming growth factor-beta signaling through direct interaction of YB-1 with Smad3.

PubMed

Higashi, Kiyoshi; Inagaki, Yutaka; Fujimori, Ko; Nakao, Atsuhito; Kaneko, Hideo; Nakatsuka, Iwao

2003-10-31

Transforming growth factor-beta (TGF-beta) and interferon-gamma (IFN-gamma) exert antagonistic effects on collagen synthesis in human dermal fibroblasts. We have recently shown that Y box-binding protein YB-1 mediates the inhibitory effects of IFN-gamma on alpha2(I) procollagen gene (COL1A2) transcription through the IFN-gamma response element located between -161 and -150. Here we report that YB-1 counter-represses TGF-beta-stimulated COL1A2 transcription by interfering with Smad3 bound to the upstream sequence around -265 and subsequently by interrupting the Smad3-p300 interaction. Western blot and immunofluorescence analyses using inhibitors for Janus kinases or casein kinase II suggested that the casein kinase II-dependent signaling pathway mediates IFN-gamma-induced nuclear translocation of YB-1. Down-regulation of endogenous YB-1 expression by double-stranded YB-1-specific RNA abrogated the transcriptional repression of COL1A2 by IFN-gamma in the absence and presence of TGF-beta. In transient transfection assays, overexpression of YB-1 in human dermal fibroblasts exhibited antagonistic actions against TGF-beta and Smad3. Physical interaction between Smad3 and YB-1 was demonstrated by immunoprecipitation-Western blot analyses, and electrophoretic mobility shift assays using the recombinant Smad3 and YB-1 proteins indicated that YB-1 forms a complex with Smad3 bound to the Smad-binding element. Glutathione S-transferase pull-down assays showed that YB-1 binds to the MH1 domain of Smad3, whereas the central and carboxyl-terminal regions of YB-1 were required for its interaction with Smad3. YB-1 also interferes with the Smad3-p300 interaction by its preferential binding to p300. Altogether, the results provide a novel insight into the mechanism by which IFN-gamma/YB-1 counteracts TGF-beta/Smad3. They also indicate that IFN-gamma/YB-1 inhibits COL1A2 transcription by dual actions: via the IFN-gamma response element and through a cross-talk with the TGF

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

EPA Science Inventory

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

Muscular exercise can cause highly pathological liver function tests in healthy men.

PubMed

Pettersson, Jonas; Hindorf, Ulf; Persson, Paula; Bengtsson, Thomas; Malmqvist, Ulf; Werkström, Viktoria; Ekelund, Mats

2008-02-01

The occurrence of idiosyncratic drug hepatotoxicity is a major problem in all phases of clinical drug development and the leading cause of postmarketing warnings and withdrawals. Physical exercise can result in transient elevations of liver function tests. There is no consensus in the literature on which forms of exercise may cause changes in liver function tests and to what extent. Weightlifting results in profound increases in liver function tests in healthy men used to moderate physical activity, not including weightlifting. Liver function tests are significantly increased for at least 7 days after weightlifting. It is important to impose relevant restrictions on heavy muscular exercise prior to and during clinical studies. To investigate the effect of intensive muscular exercise (weightlifting) on clinical chemistry parameters reflecting liver function in healthy men. Fifteen healthy men, used to moderate physical activity not including weightlifting, performed an 1 h long weightlifting programme. Blood was sampled for clinical chemistry parameters [aspartate aminotransferase (AST), alanine aminotransferase (ALT), lactate dehydrogenase (LD), gamma-glutamyl transferase (gamma GT), alkaline phosphatase (ALP), bilirubin, creatine kinase (CK) and myoglobin] at repeated intervals during 7 days postexercise and at a follow-up examination 10-12 days postexercise. Five out of eight studied clinical chemistry parameters (AST, ALT, LD, CK and myoglobin) increased significantly after exercise (P < 0.01) and remained increased for at least 7 days postexercise. Bilirubin, gamma GT and ALP remained within the normal range. The liver function parameters, AST and ALT, were significantly increased for at least 7 days after the exercise. In addition, LD and, in particular, CK and myoglobin showed highly elevated levels. These findings highlight the importance of imposing restrictions on weightlifting prior to and during clinical studies. Intensive muscular exercise, e

Combined therapy with danazol, pegilated interferon, and ribavirin improves thrombocytopenia and liver injury in rats with fibrosis.

PubMed

Alvarez, Guillermo Cabrera; Madrid-Marina, Vicente; Jimenez-Mendez, Ricardo; Buitimea, Angel Leon; Román, Margarita Bahena; Cortez-Gomez, Rudyard; Esparza, Jorge Reyes; Rodríguez-Fragoso, Lourdes

2007-01-01

The aim of this study was to investigate the effects of combinations of pegilated-interferon (PEG-IFN), ribavirin, and danazol on thrombocytopenia and liver injury in rats with fibrosis. Male adult Wistar rats were treated with either mineral oil, danazol (0.83 mg/kg per day), PEG-interferon alpha-2a (PEG-IFN, 0.3 microg/ week) + ribavirin (12 mg/kg per day), PEG-IFN + ribavirin + danazol, CCl(4) (4 g/kg for eight weeks), CCl(4) + PEG-IFN + ribavirin, or CCl(4) + PEG-IFN + ribavirin+ danazol. The following assays were conducted: hematology, clinical chemistry, liver function, liver fibrosis, lymphocyte cytokine mRNA expression, and bone-marrow DNA content. Platelet counts were low in sham-treated animals and animals treated with PEG- IFN + ribavirin (30% and 25% respectively; P < 0.05). PEG-IFN + ribavirin + danazol reduced platelet counts of fibrotic animals by only 9% (P < 0.05). PEG- IFN + ribavirin reduced hepatic collagen content by 50%, whereas danazol + PEG-IFN + ribavirin reduced hepatic collagen content by 60% (P < 0.05). PEG-IFN + ribavirin reduced the total bilirubin concentration by 27%, alanine amino transferase (ALT) activity by 75% and gamma-glutamyl transpeptidase (gamma-GTP) activity by 74% (P < 0.05). In contrast, danazol + PEG-IFN + ribavirin reduced total bilirubin levels by 61%, alkaline phosphatase activity by 45%, ALT activity by 76%, and gamma-GTP activity by 74% (P < 0.05). The only treatment that increased interleukin 10 (IL-10) mRNA in fibrotic rats was PEG-IFN + ribavirin. However, danazol + PEG-IFN + ribavirin reduced the expression of IL-6, IL-10, tumor necrosis factor alpha and transforming growth factor ss. Bone-marrow DNA content was not altered by any treatment. In conclusion, PEG-IFN + ribavirin + danazol could be a new therapeutic option for patients with liver injury, fibrosis, and thrombocytopenia.

DNA BINDING POTENTIAL OF BROMODICHLOROMETHANE MEDIATED BY GLUTATHIONE S-TRANSFERASE THETA 1-1

EPA Science Inventory

DNA BINDING POTENTIAL OF BROMODICHLOROMETHANE MEDIATED BY GLUTATHIONE S-TRANSFERASE THETA 1-1. R A Pegram1 and M K Ross2. 2Curriculum in Toxicology, University of North Carolina, Chapel Hill, NC; 1Pharmacokinetics Branch, NHEERL, ORD, United States Environmental Protection Ag...

Glutathione S-transferase P1 (GSTP1) directly influences platinum drug chemosensitivity in ovarian tumour cell lines

PubMed Central

Sawers, L; Ferguson, M J; Ihrig, B R; Young, H C; Chakravarty, P; Wolf, C R; Smith, G

2014-01-01

Background: Chemotherapy response in ovarian cancer patients is frequently compromised by drug resistance, possibly due to altered drug metabolism. Platinum drugs are metabolised by glutathione S-transferase P1 (GSTP1), which is abundantly, but variably expressed in ovarian tumours. We have created novel ovarian tumour cell line models to investigate the extent to which differential GSTP1 expression influences chemosensitivity. Methods: Glutathione S-transferase P1 was stably deleted in A2780 and expression significantly reduced in cisplatin-resistant A2780DPP cells using Mission shRNA constructs, and MTT assays used to compare chemosensitivity to chemotherapy drugs used to treat ovarian cancer. Differentially expressed genes in GSTP1 knockdown cells were identified by Illumina HT-12 expression arrays and qRT–PCR analysis, and altered pathways predicted by MetaCore (GeneGo) analysis. Cell cycle changes were assessed by FACS analysis of PI-labelled cells and invasion and migration compared in quantitative Boyden chamber-based assays. Results: Glutathione S-transferase P1 knockdown selectively influenced cisplatin and carboplatin chemosensitivity (2.3- and 4.83-fold change in IC50, respectively). Cell cycle progression was unaffected, but cell invasion and migration was significantly reduced. We identified several novel GSTP1 target genes and candidate platinum chemotherapy response biomarkers. Conclusions: Glutathione S-transferase P1 has an important role in cisplatin and carboplatin metabolism in ovarian cancer cells. Inter-tumour differences in GSTP1 expression may therefore influence response to platinum-based chemotherapy in ovarian cancer patients. PMID:25010864

Characterization of a Bvg-regulated fatty acid methyl-transferase in Bordetella pertussis.

PubMed

Rivera-Millot, Alex; Lesne, Elodie; Solans, Luis; Coutte, Loic; Bertrand-Michel, Justine; Froguel, Philippe; Dhennin, Véronique; Hot, David; Locht, Camille; Antoine, Rudy; Jacob-Dubuisson, Françoise

2017-01-01

The whooping cough agent Bordetella pertussis controls the expression of its large virulence regulon in a coordinated manner through the two-component signal transduction system BvgAS. In addition to the genes coding for bona fide virulence factors, the Bvg regulon comprises genes of unknown function. In this work, we characterized a new Bvg-activated gene called BP2936. Homologs of BP2936 are found in other pathogenic Bordetellae and in several other species, including plant pathogens and environmental bacteria. We showed that the gene product of BP2936 is a membrane-associated methyl-transferase of free fatty acids. We thus propose to name it FmtB, for fatty acid methyl-transferase of Bordetella. The role of this protein was tested in cellular and animal models of infection, but the loss of BP2936 did not appear to affect host-pathogen interactions in those assays. The high level of conservation of BP2936 among B. pertussis isolates nevertheless argues that it probably plays a role in the life cycle of this pathogen.

The role of endoxyloglucan transferase in the organization of plant cell walls.

PubMed

Nishitani, K

1997-01-01

The plant cell wall plays a central role in morphogenesis as well as responsiveness to environmental signals. Xyloglucans are the principal component of the plant cell wall matrix and serve as cross-links between cellulose microfibrils to form the cellulose-xyloglucan framework. Endoxyloglucan transferase (EXGT), which was isolated and characterized in 1992, is an enzyme that mediates molecular grafting reaction between xyloglucan molecules. Structural studies on cDNAs encoding EXGT and its related proteins have disclosed the ubiquitous presence in the plant kingdom of a large multigene family of xyloglucan-related proteins (XRPs). Each XRP functions as either hydrolase or transferase acting on xyloglucans and is considered to be responsible for rearrangement of the cellulose-xyloglucan framework, the processes essential for the construction, modification, and degradation of plant cell walls. Different XRP genes exhibit potentially different expression profiles with respect to tissue specificity and responsiveness to hormonal and mechanical signals. The molecular approach to individual XRP genes will open a new path for exploring the controlling mechanisms by which the plant cell wall is constructed and reformed during plant growth and development.

Characterization of a Bvg-regulated fatty acid methyl-transferase in Bordetella pertussis

PubMed Central

Rivera-Millot, Alex; Lesne, Elodie; Solans, Luis; Coutte, Loic; Bertrand-Michel, Justine; Froguel, Philippe; Dhennin, Véronique; Hot, David; Locht, Camille; Antoine, Rudy

2017-01-01

The whooping cough agent Bordetella pertussis controls the expression of its large virulence regulon in a coordinated manner through the two-component signal transduction system BvgAS. In addition to the genes coding for bona fide virulence factors, the Bvg regulon comprises genes of unknown function. In this work, we characterized a new Bvg-activated gene called BP2936. Homologs of BP2936 are found in other pathogenic Bordetellae and in several other species, including plant pathogens and environmental bacteria. We showed that the gene product of BP2936 is a membrane-associated methyl-transferase of free fatty acids. We thus propose to name it FmtB, for fatty acid methyl-transferase of Bordetella. The role of this protein was tested in cellular and animal models of infection, but the loss of BP2936 did not appear to affect host-pathogen interactions in those assays. The high level of conservation of BP2936 among B. pertussis isolates nevertheless argues that it probably plays a role in the life cycle of this pathogen. PMID:28493897

A Tyrosine-Reactive Irreversible Inhibitor for Glutathione S-Transferase Pi (GSTP1)

PubMed Central

Crawford, L. A.; Weerapana, E.

2016-01-01

Glutathione S-Transferase Pi (GSTP1) mediates cellular defense against reactive electrophiles. Here, we report LAS17, a dichlorotriazine-containing compound that irreversibly inhibits GSTP1 and is selective for GSTP1 within cellular proteomes. Mass spectrometry and mutational studies identified Y108 as the site of modification, providing a unique mode of GSTP1 inhibition. PMID:27113843

A tyrosine-reactive irreversible inhibitor for glutathione S-transferase Pi (GSTP1).

PubMed

Crawford, L A; Weerapana, E

2016-05-24

Glutathione S-transferase Pi (GSTP1) mediates cellular defense against reactive electrophiles. Here, we report LAS17, a dichlorotriazine-containing compound that irreversibly inhibits GSTP1 and is selective for GSTP1 within cellular proteomes. Mass spectrometry and mutational studies identified Y108 as the site of modification, providing a unique mode of GSTP1 inhibition.

Predictors of fibrosis in Asian patients with non-alcoholic steatohepatitis.

PubMed

Tsang, Steven Woon Choy; Ng, Wing Fung; Wu, Brian Ping Ying; Chow, David Alan; Li, Eric Ting Ho; Wong, Tak Cheung

2006-01-01

Non-alcoholic steatohepatitis (NASH) is increasingly recognized as an important cause of chronic liver disease. However, data on Asians with NASH is lacking in the literature. The aim of the present study was to describe the clinical, biochemical and histological characteristics of NASH in Asians and to determine the predictors for septal fibrosis. Sixty consecutive patients aged over 18 years with elevated serum alanine transferase, sonographic evidence of steatosis, and consent for liver biopsy were included. Patients with chronic hepatitis B or C, alcoholic, autoimmune, genetic, or drug-induced liver disease were excluded. Clinical, biochemical and histological variables were tested for association with septal liver fibrosis (F2/3). Median age of the cohort was 45.5 years (range 21-75 years) and 63% were male. Ninety percent of patients were obese (body mass index [BMI]>or= 25), 70% had hypertriglyceridemia, 68% had hypercholesterolemia, 58% had metabolic syndrome, 53% had hypertension, 47% had diabetes mellitus (DM), and 18% had obstructive sleep apnea. Sixty-eight percent had gamma-glutamyl transferase (GGT) >or= 2 x upper limit of normal (ULN), 55% had alanine aminotransferase (ALT) >or= 2 x ULN, and 23% had aspartate aminotransferase (AST) >or= 2 x ULN. Of the 40 non-diabetic patients undergoing oral glucose tolerance testing, 45% had normal tests, 30% had impaired glucose tolerance, 23% DM, and 2% impaired fasting glucose. Eighteen patients (30%) had septal fibrosis (F2/3), but none had cirrhosis. Necroinflammatory grade >or= 2 (odds ratio [OR] 13), AST >or= 2 x ULN (OR 5.3) and DM (OR 5) were significantly and independently correlated with septal fibrosis. Septal fibrosis is common in Asians with NASH. Necroinflammatory grade >or= 2, AST >or= 2 x ULN and DM are independent predictors for septal fibrosis.

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

PubMed

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

2017-07-01

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

The gamma-glutamyl transpeptidase-to-platelet ratio predicts liver fibrosis and cirrhosis in HBeAg-positive chronic HBV infection patients with high HBV DNA and normal or mildly elevated alanine transaminase levels in China.

PubMed

Li, Q; Li, W; Huang, Y; Chen, L

2016-11-01

The gamma-glutamyl transpeptidase-to-platelet ratio (GPR) is a new serum diagnostic model, which is reported to be more accurate than aspartate transaminase-to-platelet ratio index (APRI) and fibrosis index based on the four factors (Fib-4) for the diagnosis of significant fibrosis and cirrhosis in chronic HBV infection (CHBVI) patients in West Africa. To evaluate the performance of the GPR model for the diagnosis of liver fibrosis and cirrhosis in HBeAg-positive CHBVI patients with high HBV DNA (≥5 log 10 copies/mL) and normal or mildly elevated alanine transaminase (ALT) (≤2 times upper limit of normal (ULN)) in China. A total of 1521 consecutive CHBVI patients who underwent liver biopsies and routine laboratory tests were retrospectively screened. Of these patients, 401 treatment naïve HBeAg-positive patients with HBV DNA≥5 log 10 copies/mL and ALT≤2 ULN were included. The METAVIR scoring system was adopted as the pathological diagnosis standard of liver fibrosis. Using liver histology as a gold standard, the performances of GPR, APRI, and Fib-4 for the diagnosis of liver fibrosis and cirrhosis were evaluated and compared by receiver operating characteristic (ROC) curves and the area under the ROC curves (AUROCs). Of 401 patients, 121 (30.2%), 49 (12.2%) and 17 (4.2%) were classified as having significant fibrosis (≥F2), severe fibrosis (≥F3) and cirrhosis (=F4), respectively. After estimating the AUROC to predict significant fibrosis, the performance of GPR (AUROC=0.66, 95% CI 0.60-0.72) was higher than APRI (AUROC=0.58, 95% CI 0.52-0.64, P=.002) and Fib-4 scores (AUROC=0.54, 95% CI 0.47-0.60, P<.001). After estimating the AUROC to predict severe fibrosis, the performance of GPR (AUROC=0.71, 95% CI 0.63-0.80) was also higher than APRI (AUROC=0.65, 95% CI 0.56-0.73, P=.003) and Fib-4 scores (AUROC=0.67, 95% CI 0.58-0.75, P=.001). After estimating the AUROC to predict cirrhosis, the performance of GPR (AUROC=0.73, 95% CI 0.56-0.88) was higher than

Anticonvulsant properties of alpha, gamma, and alpha, gamma-substituted gamma-butyrolactones.

PubMed

Klunk, W E; Covey, D F; Ferrendelli, J A

1982-09-01

Derivatives of gamma-butyrolactone (GBL) substituted on the alpha- and/or gamma-positions were synthesized and tested for their effects on behavior in mice, on the electroencephalographs and blood pressure of paralyzed-ventilated guinea pigs, and on electrical activity of incubated hippocampal slices. Several compounds, including alpha-ethyl-alpha-methyl GBL (alpha-EMGBL), alpha, alpha-dimethyl GBL, alpha, gamma-diethyl-alpha, gamma-dimethyl GBL, and gamma-ethyl-gamma-methyl GBL, prevented seizures induced by pentylenetetrazol, beta-ethyl-beta-methyl-gamma-butyrolactone (beta-EMGBL), picrotoxin, or all three compounds in mice and guinea pigs but had no effect on seizures induced by maximal electroshock or bicuculline. Neither gamma-hydroxybutyrate (GHB) nor alpha-isopropylidine GBL had any anticonvulsant activity. The anticonvulsant alpha-substituted compounds had a potent hypotensive effect and antagonized the hypertensive effect of beta-EMGBL, alpha-EMGBL was tested in incubated hippocampal slices and was found to depress basal activity and antagonize excitation induced by beta-EMGBL. These results demonstrate that alpha-alkyl-substituted GBL and, to a lesser extent, gamma-substituted derivatives are anticonvulsant agents and that their effects are strikingly different from those of GHB or beta-alkyl-substituted GBLs, which are epileptogenic. Possibly beta- and alpha-substituted GBLs act at the same site as agonists and antagonists, respectively.

Drug resistance in epithelial ovarian cancer: P-glycoprotein and glutation S-transferase. Can they play an important role in detecting response to platinum-based chemotherapy as a first-line therapy.

PubMed

Simşek, T; Ozbilim, G; Gülkesen, H; Kaya, H; Sargin, F; Karaveli, S

2001-01-01

Drug resistance is important for the treatment of ovarian cancer. P-glycoprotein and glutation S-transferase as resistance markers play an important role in the effectivity of chemotherapeutical agents. The role of P-glycoprotein and glutation S-transferase in the treatment of epithelial ovarian cancer is not well understood. We investigated the relation between P-glycoprotein and glutation S-transferase level for response to platinum-based chemotherapy in epithelial ovarian cancer. We reviewed 30 cases diagnosed as epithelial ovarian cancer and treated with platinum-based chemotherapy in the Department of Obstetrics and Gynecology, Akdeniz University School of Medicine. The material was attained from initial parafin-embeded blocks stained for P-glycoprotein and glutation S-transferase. The cases that were diagnosed and treated before attending our clinic were not enrolled in the study. Mean age was 58.2 (25-70) and mean gravida 4.1 (0-10). Twenty-four patients (80%) were glutation S-transferase positive. Three cases (10%) out of 30 had positive reaction for P-glycoprotein. No difference was revealed regarding chemotherapy response rate among the cases showing glutation S-transferase positivity and P-glycoprotein negativity. Detection of glutation S-transferase and P-glycoprotein levels in epithelial ovarian cancer tissue is not important for response to platinum-based chemotherapy as a first line.

β(1,3)-Glucanosyl-Transferase Activity Is Essential for Cell Wall Integrity and Viability of Schizosaccharomyces pombe

PubMed Central

de Medina-Redondo, María; Arnáiz-Pita, Yolanda; Clavaud, Cécile; Fontaine, Thierry; del Rey, Francisco; Latgé, Jean Paul; Vázquez de Aldana, Carlos R.

2010-01-01

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. PMID:21124977

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

ERIC Educational Resources Information Center

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

2018-01-01

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

Identification of Glutathione S-Transferase Pi as a Protein Involved in Parkinson Disease Progression

PubMed Central

Shi, Min; Bradner, Joshua; Bammler, Theo K.; Eaton, David L.; Zhang, JianPeng; Ye, ZuCheng; Wilson, Angela M.; Montine, Thomas J.; Pan, Catherine; Zhang, Jing

2009-01-01

Parkinson disease (PD) typically affects the cortical regions during the later stages of disease, with neuronal loss, gliosis, and formation of diffuse cortical Lewy bodies in a significant portion of patients with dementia. To identify novel proteins involved in PD progression, we prepared synaptosomal fractions from the frontal cortices of pathologically verified PD patients at different stages along with age-matched controls. Protein expression profiles were compared using a robust quantitative proteomic technique. Approximately 100 proteins displayed significant differences in their relative abundances between PD patients at various stages and controls; three of these proteins were validated using independent techniques. One of the confirmed proteins, glutathione S-transferase Pi, was further investigated in cellular models of PD, demonstrating that its level was intimately associated with several critical cellular processes that are directly related to neurodegeneration in PD. These results have, for the first time, suggested that the levels of glutathione S-transferase Pi may play an important role in modulating the progression of PD. PMID:19498008

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

PubMed

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

2001-05-18

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

γ-glutamyl transpeptidase 1 specifically suppresses green-light avoidance via GABAA receptors in Drosophila.

PubMed

Liu, Jiangqu; Gong, Zhefeng; Liu, Li

2014-08-01

Drosophila larvae innately show light avoidance behavior. Compared with robust blue-light avoidance, larvae exhibit relatively weaker green-light responses. In our previous screening for genes involved in larval light avoidance, compared with control w(1118) larvae, larvae with γ-glutamyl transpeptidase 1 (Ggt-1) knockdown or Ggt-1 mutation were found to exhibit higher percentage of green-light avoidance which was mediated by Rhodopsin6 (Rh6) photoreceptors. However, their responses to blue light did not change significantly. By adjusting the expression level of Ggt-1 in different tissues, we found that Ggt-1 in malpighian tubules was both necessary and sufficient for green-light avoidance. Our results showed that glutamate levels were lower in Ggt-1 null mutants compared with controls. Feeding Ggt-1 null mutants glutamate can normalize green-light avoidance, indicating that high glutamate concentrations suppressed larval green-light avoidance. However, rather than directly, glutamate affected green-light avoidance indirectly through GABA, the level of which was also lower in Ggt-1 mutants compared with controls. Mutants in glutamate decarboxylase 1, which encodes GABA synthase, and knockdown lines of the GABAA receptor, both exhibit elevated levels of green-light avoidance. Thus, our results elucidate the neurobiological mechanisms mediating green-light avoidance, which was inhibited in wild-type larvae. © 2014 International Society for Neurochemistry.

Imidazopyridine and Pyrazolopiperidine Derivatives as Novel Inhibitors of Serine Palmitoyl Transferase.

PubMed

Genin, Michael J; Gonzalez Valcarcel, Isabel C; Holloway, William G; Lamar, Jason; Mosior, Marian; Hawkins, Eric; Estridge, Thomas; Weidner, Jeffrey; Seng, Thomas; Yurek, David; Adams, Lisa A; Weller, Jennifer; Reynolds, Vincent L; Brozinick, Joseph T

2016-06-23

To develop novel treatments for type 2 diabetes and dyslipidemia, we pursued inhibitors of serine palmitoyl transferase (SPT). To this end compounds 1 and 2 were developed as potent SPT inhibitors in vitro. 1 and 2 reduce plasma ceramides in rodents, have a slight trend toward enhanced insulin sensitization in DIO mice, and reduce triglycerides and raise HDL in cholesterol/cholic acid fed rats. Unfortunately these molecules cause a gastric enteropathy after chronic dosing in rats.

Uptake and speciation of selenium in garlic cultivated in soil amended with symbiotic fungi (mycorrhiza) and selenate.

PubMed

Larsen, Erik H; Lobinski, Ryszard; Burger-Meÿer, Karin; Hansen, Marianne; Ruzik, Rafal; Mazurowska, Lena; Rasmussen, Peter Have; Sloth, Jens J; Scholten, Olga; Kik, Chris

2006-07-01

The scope of the work was to investigate the influence of selenate fertilisation and the addition of symbiotic fungi (mycorrhiza) to soil on selenium and selenium species concentrations in garlic. The selenium species were extracted from garlic cultivated in experimental plots by proteolytic enzymes, which ensured liberation of selenium species contained in peptides or proteins. Separate extractions using an aqueous solution of enzyme-deactivating hydroxylamine hydrochloride counteracted the possible degradation of labile selenium species by enzymes (such as alliinase) that occur naturally in garlic. The selenium content in garlic, which was analysed by ICP-MS, showed that addition of mycorrhiza to the natural soil increased the selenium uptake by garlic tenfold to 15 microg g(-1) (dry mass). Fertilisation with selenate and addition of mycorrhiza strongly increased the selenium content in garlic to around one part per thousand. The parallel analysis of the sample extracts by cation exchange and reversed-phase HPLC with ICP-MS detection showed that gamma-glutamyl-Se-methyl-selenocysteine amounted to 2/3, whereas methylselenocysteine, selenomethionine and selenate each amounted to a few percent of the total chromatographed selenium in all garlic samples. Se-allyl-selenocysteine and Se-propyl-selenocysteine, which are selenium analogues of biologically active sulfur-containing amino acids known to occur in garlic, were searched for but not detected in any of the extracts. The amendment of soil by mycorrhiza and/or by selenate increased the content of selenium but not the distribution of detected selenium species in garlic. Finally, the use of two-dimensional HPLC (size exclusion followed by reversed-phase) allowed the structural characterisation of gamma-glutamyl-Se-methyl-selenocysteine and gamma-glutamyl-Se-methyl-selenomethionine in isolated chromatographic fractions by quadrupole time-of-flight mass spectrometry.

BIOCHEMICAL EFFECTS IN NORMAL AND STONE FORMING RATS TREATED WITH THE RIPE KERNEL JUICE OF PLANTAIN (MUSA PARADISIACA)

PubMed Central

Devi, V. Kalpana; Baskar, R.; Varalakshmi, P.

1993-01-01

The effect of Musa paradisiaca stem kernel juice was investigated in experimental urolithiatic rats. Stone forming rats exhibited a significant elevation in the activities of two oxalate synthesizing enzymes - Glycollic acid oxidase and Lactate dehydrogenase. Deposition and excretion of stone forming constituents in kidney and urine were also increased in these rats. The enzyme activities and the level of crystalline components were lowered with the extract treatment. The extract also reduced the activities of urinary alkaline phosphatase, lactate dehydrogenase, r-glutamyl transferase, inorganic pyrophosphatase and β-glucuronidase in calculogenic rats. No appreciable changes were noticed with leucine amino peptidase activity in treated rats. PMID:22556626

Evaluation of the Protective Role of Vitamin C on the Metabolic and Enzymatic Activities of the Liver in the Male Rats After Exposure to 2.45 GHz Of Wi-Fi Routers.

PubMed

Shekoohi-Shooli, F; Mortazavi, S M J; Shojaei-Fard, M B; Nematollahi, S; Tayebi, M

2016-09-01

The use of devices emitted microwave radiation such as mobile phones, wireless fidelity (Wi-Fi) routers, etc. is increased rapidly. It has caused a great concern; the researchers should identify its effects on people's health. We evaluated the protective role of Vitamin C on the metabolic and enzymatic activities of the liver after exposure to Wi-Fi routers. 70 male Wistar rats weighing 200-250 g were randomly divided into 7 groups (10 rats in each group).The first stage one -day test: Group A (received vitamin C 250 mg/kg/day orally together with 8- hour/day Wi-Fi exposure).Group B (exposed to Wi-Fi radiation). Group C (received vitamin C). Group D or Control (was neither exposed to radiation of Wi-Fi modem nor did receive vitamin C). The second phase of experiment had done for five consecutive days. It involved Group E (received vitamin C), Group F (exposed to Wi-Fi radiation), Group G (received vitamin C together with Wi-Fi radiation). The distance between animals' restrainers was 20 cm away from the router antenna. Finally, blood samples were collected and assayed the level of hepatic enzymes including alkaline phosphatase(ALP), alanine amino transferase(ALT) aspartate amino transferase (ASL), gamma glutamyl transferase (GGT) and the concentration of Blood Glucose, Cholesterol , Triglyceride(TG),High density lipoprotein (HDL)and low density lipoprotein (LDL). Data obtained from the One day test showed an increase in concentration of blood glucose, decrease in Triglyceride level and GGT factor (P<0.05), however no observed significant difference on the Cholesterol , HDL , LDL level and hepatic enzymes activities in compare to control group. Groups of the five-day test showed reduction in the amount of blood glucose, elevation of cholesterol level and LDL relative to control group(P<0.05). WiFi exposure may exert alternations on the metabolic parameters and hepatic enzymes activities through stress oxidative and increasing of free radicals, but the use of vitamin

Evaluation of the Protective Role of Vitamin C on the Metabolic and Enzymatic Activities of the Liver in the Male Rats After Exposure to 2.45 GHz Of Wi-Fi Routers

PubMed Central

Shekoohi-Shooli, F.; Mortazavi, S.M.J.; Shojaei-fard, M.B.; Nematollahi, S.; Tayebi, M.

2016-01-01

Background: The use of devices emitted microwave radiation such as mobile phones, wireless fidelity (Wi-Fi) routers, etc. is increased rapidly. It has caused a great concern; the researchers should identify its effects on people’s health. We evaluated the protective role of Vitamin C on the metabolic and enzymatic activities of the liver after exposure to Wi-Fi routers. Material and Methods: 70 male Wistar rats weighing 200-250 g were randomly divided into 7 groups (10 rats in each group).The first stage one -day test: Group A (received vitamin C 250 mg/kg/day orally together with 8- hour/day Wi-Fi exposure).Group B (exposed to Wi-Fi radiation). Group C (received vitamin C). Group D or Control (was neither exposed to radiation of Wi-Fi modem nor did receive vitamin C). The second phase of experiment had done for five consecutive days. It involved Group E (received vitamin C), Group F (exposed to Wi-Fi radiation), Group G (received vitamin C together with Wi-Fi radiation). The distance between animals’ restrainers was 20 cm away from the router antenna. Finally, blood samples were collected and assayed the level of hepatic enzymes including alkaline phosphatase(ALP), alanine amino transferase(ALT) aspartate amino transferase (ASL), gamma glutamyl transferase (GGT) and the concentration of Blood Glucose, Cholesterol , Triglyceride(TG),High density lipoprotein (HDL)and low density lipoprotein (LDL). Results: Data obtained from the One day test showed an increase in concentration of blood glucose, decrease in Triglyceride level and GGT factor (P<0.05), however no observed significant difference on the Cholesterol , HDL , LDL level and hepatic enzymes activities in compare to control group. Groups of the five-day test showed reduction in the amount of blood glucose, elevation of cholesterol level and LDL relative to control group(P<0.05). Conclusion: WiFi exposure may exert alternations on the metabolic parameters and hepatic enzymes activities through stress

Antiurolithiatic Effect of Sirupeelai Samoola Kudineer: A Polyherbal Siddha Decoction on Ethylene Glycol-induced Renal Calculus in Experimental Rats

PubMed Central

Vasanthi, A. Hannah Rachel; Muthulakshmi, V.; Gayathri, V.; Manikandan, R.; Ananthi, S.; Kuruvilla, Sarah

2017-01-01

functional protection against ethylene glycol- induced renal calculus in rats as evidenced by histopathological studies. Abbreviations used: SK: Sirupeelai Samoola Kudineer; TBARS: ThioBarbituric Acid Reactive Substances; SOD: SuperOxide Dismutase; GPx: Gluthathione peroxidase; GSH- Glutathione; LPO: Lipid peroxidation as measured as TBARS; AST: Aspartate AminoTransferase; ALT: Alanine Amino transferase; GGT: Gamma Glutamyl Transferase; LDH: Lactate Dehydrogenase. PMID:28808392

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

USDA-ARS?s Scientific Manuscript database

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

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

PubMed

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

2015-02-01

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

Pleiotropic Functions of Glutathione S-Transferase P

PubMed Central

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

2016-01-01

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

Testing of an oral dosing technique for double-crested cormorants, Phalacocorax auritus, laughing gulls, Leucophaeus atricilla, homing pigeons, Columba livia, and western sandpipers, Calidris mauri, with artificially weather MC252 oil.

PubMed

Dean, K M; Cacela, D; Carney, M W; Cunningham, F L; Ellis, C; Gerson, A R; Guglielmo, C G; Hanson-Dorr, K C; Harr, K E; Healy, K A; Horak, K E; Isanhart, J P; Kennedy, L V; Link, J E; Lipton, I; McFadden, A K; Moye, J K; Perez, C R; Pritsos, C A; Pritsos, K L; Muthumalage, T; Shriner, S A; Bursian, S J

2017-12-01

Scoping studies were designed to determine if double-crested cormorants (Phalacocorax auritus), laughing gulls (Leucophaues atricilla), homing pigeons (Columba livia) and western sandpipers (Calidris mauri) that were gavaged with a mixture of artificially weathered MC252 oil and food for either a single day or 4-5 consecutive days showed signs of oil toxicity. Where volume allowed, samples were collected for hematology, plasma protein electrophoresis, clinical chemistry and electrolytes, oxidative stress and organ weigh changes. Double-crested cormorants, laughing gulls and western sandpipers all excreted oil within 30min of dose, while pigeons regurgitated within less than one hour of dosing. There were species differences in the effectiveness of the dosing technique, with double-crested cormorants having the greatest number of responsive endpoints at the completion of the trial. Statistically significant changes in packed cell volume, white cell counts, alkaline phosphatase, alanine aminotransferase, creatine phosphokinase, gamma glutamyl transferase, uric acid, chloride, sodium, potassium, calcium, total glutathione, glutathione disulfide, reduced glutathione, spleen and liver weights were measured in double-crested cormorants. Homing pigeons had statistically significant changes in creatine phosphokinase, total glutathione, glutathione disulfide, reduced glutathione and Trolox equivalents. Laughing gulls exhibited statistically significant decreases in spleen and kidney weight, and no changes were observed in any measurement endpoints tested in western sandpipers. Copyright © 2017 Elsevier Inc. All rights reserved.

Hepatoprotective activity of bacoside A against N-nitrosodiethylamine-induced liver toxicity in adult rats.

PubMed

Janani, Panneerselvam; Sivakumari, Kanakarajan; Parthasarathy, Chandrakesan

2009-10-01

N-Nitrosodiethylamine (DEN) is a notorious carcinogen, present in many environmental factors. DEN induces oxidative stress and cellular injury due to enhanced generation of reactive oxygen species; free radical scavengers protect the membranes from DEN-induced damage. The present study was designed to evaluate the protective effect of bacoside A (the active principle isolated from Bacopa monniera Linn.) on carcinogen-induced damage in rat liver. Adult male albino rats were pretreated with 15 mg/kg body weight/day of bacoside A orally (for 14 days) and then intoxicated with single necrogenic dose of N-nitrosodiethylamine (200 mg/kg bodyweight, intraperitonially) and maintained for 7 days. The liver weight, lipid peroxidation (LPO), and activity of serum marker enzymes (aspartate transaminases, alanine transaminases, lactate dehydrogenase, alkaline phosphatase, and gamma-glutamyl transpeptidase) were markedly increased in carcinogen-administered rats, whereas the activities of marker enzymes were near normal in bacoside A-pretreated rats. Activities of antioxidant enzymes (superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, glutatione-S-transferase, and reduced glutathione) in liver also decreased in carcinogen-administered rats, which were significantly elevated in bacoside A-pretreated rats. It is concluded that pretreatment of bacoside A prevents the elevation of LPO and activity of serum marker enzymes and maintains the antioxidant system and thus protects the rats from DEN-induced hepatotoxicity.

Protective effect of sulforaphane against oxidative stress: recent advances.

PubMed

Guerrero-Beltrán, Carlos Enrique; Calderón-Oliver, Mariel; Pedraza-Chaverri, José; Chirino, Yolanda Irasema

2012-07-01

Sulforaphane [1-isothiocyanate-(4R)-(methylsulfinyl)butane] is a natural dietary isothiocyanate produced by the enzymatic action of the myrosinase on glucopharanin, a 4-methylsulfinylbutyl glucosinolate contained in cruciferous vegetables of the genus Brassica such as broccoli, brussel sprouts, and cabbage. Studies on this compound is increasing because its anticarcinogenic and cytoprotective properties in several in vivo experimental paradigms associated with oxidative stress such as focal cerebral ischemia, brain inflammation, intracerebral hemorrhage, ischemia and reperfusion induced acute renal failure, cisplatin induced-nephrotoxicity, streptozotocin-induced diabetes, carbon tetrachloride-induced hepatotoxicity and cardiac ischemia and reperfusion. This protective effect also has been observed in in vitro studies in different cell lines such as human neuroblastoma SH-SY5Y, renal epithelial proximal tubule LLC-PK1 cells and aortic smooth muscle A10 cells. Sulforaphane is considered an indirect antioxidant; this compound is able to induce many cytoprotective proteins, including antioxidant enzymes, through the Nrf2-antioxidant response element pathway. Heme oxygenase-1, NAD(P)H: quinone oxidoreductase, glutathione-S-transferase, gamma-glutamyl cysteine ligase, and glutathione reductase are among the cytoprotective proteins induced by sulforaphane. In conclusion, sulforaphane is a promising antioxidant agent that is effective to attenuate oxidative stress and tissue/cell damage in different in vivo and in vitro experimental paradigms. Copyright © 2010 Elsevier GmbH. All rights reserved.

A survey of feline leukaemia virus infection of domestic cats from selected areas in Harare, Zimbabwe.

PubMed

Muchaamba, Francis; Mutiringindi, Takudzwa H; Tivapasi, Musavenga T; Dhliwayo, Solomon; Matope, Gift

2014-11-14

A cross-sectional study was conducted to detect the feline leukaemia virus (FeLV) p27 antigen and to determine risk factors and the haematological changes associated with infection in domestic cats in Zimbabwe. Sera were collected for detection of the p27 antigen, urea, creatinine, alanine aminotransferase and gamma-glutamyl transferase levels, whilst whole blood was collected for haematology. FeLV p27 antigen was detected using a rapid enzyme-linked immunosorbent assay (ELISA) test kit. Data on risk factors were analysed using a logistic regression model. Of the 100 cats tested, 41% (95% CI: 31.19% - 50.81%) (41/100) were positive for the FeLV p27 antigen. Sex and health status of cats were not significantly (p > 0.05) associated with infection. Intact cats (OR = 9.73), those living in multicat housing (OR = 5.23) and cats that had access to outdoor life (OR = 35.5) were found to have higher odds of infection compared with neutered cats, those living in single-cat housing, and without access to outdoor life, respectively. Biochemistry and haematology revealed no specific changes. The results showed that FeLV infection was high in sampled cats, providing evidence of active infection. Thus, it would be prudent to introduce specific control measures for FeLV infection in Zimbabwe.

Independent Prognostic Value of Serum Markers in Diffuse Large B-Cell Lymphoma in the Era of the NCCN-IPI.

PubMed

Melchardt, Thomas; Troppan, Katharina; Weiss, Lukas; Hufnagl, Clemens; Neureiter, Daniel; Tränkenschuh, Wolfgang; Schlick, Konstantin; Huemer, Florian; Deutsch, Alexander; Neumeister, Peter; Greil, Richard; Pichler, Martin; Egle, Alexander

2015-12-01

Several serum parameters have been evaluated for adding prognostic value to clinical scoring systems in diffuse large B-cell lymphoma (DLBCL), but none of the reports used multivariate testing of more than one parameter at a time. The goal of this study was to validate widely available serum parameters for their independent prognostic impact in the era of the National Comprehensive Cancer Network-International Prognostic Index (NCCN-IPI) score to determine which were the most useful. This retrospective bicenter analysis includes 515 unselected patients with DLBCL who were treated with rituximab and anthracycline-based chemoimmunotherapy between 2004 and January 2014. Anemia, high C-reactive protein, and high bilirubin levels had an independent prognostic value for survival in multivariate analyses in addition to the NCCN-IPI, whereas neutrophil-to-lymphocyte ratio, high gamma-glutamyl transferase levels, and platelets-to-lymphocyte ratio did not. In our cohort, we describe the most promising markers to improve the NCCN-IPI. Anemia and high C-reactive protein levels retain their power in multivariate testing even in the era of the NCCN-IPI. The negative role of high bilirubin levels may be associated as a marker of liver function. Further studies are warranted to incorporate these markers into prognostic models and define their role opposite novel molecular markers. Copyright © 2015 by the National Comprehensive Cancer Network.

Metabolic changes and induction of hepatic lipidosis during feed restriction in llamas.

PubMed

Tornquist, S J; Cebra, C K; Van Saun, R J; Smith, B B; Mattoon, J S

2001-07-01

To determine whether feed restriction induces hepatic lipidosis (HL) in llamas and to evaluate the metabolic changes that develop during feed restriction. 8 healthy adult female llamas. Llamas were fed grass hay at a rate of 0.25% of their body weight per day for 13 to 28 days. Llamas were monitored by use of clinical observation, serum biochemical analyses, and ultrasound-guided liver biopsies. All 8 llamas lost weight and mobilized fat. Five llamas developed HL, including 4 that were nursing crias. During the period of feed restriction, mean serum concentration of bile acids and activities of aspartate aminotransferase (AST), sorbitol dehydrogenase (SDH), and gamma-glutamyl transferase (GGT) were significantly higher in llamas that developed HL, compared with llamas that did not. Mean insulin-to-cortisol concentration ratios were lower in llamas with HL before and up to 7 days of feed restriction, compared with those that did not develop HL. HL in llamas may be induced by severe feed restriction, particularly in the face of increased energy demand. Llamas with weight loss attributable to inadequate dietary intake may develop biochemical evidence of hepatopathy and HL. Increases in serum concentration of bile acids and activities of GGT, AST, and SDH may indicate the development of HL in llamas and identify affected animals for aggressive therapeutic intervention.

Overweight male personnel of the Japan Self-Defense Forces with body mass indices of 23.0-24.9 and obesity-related metabolic disorders.

PubMed

Sakuta, Hidenari; Suzuki, Takashi

2008-03-01

To assess the validity of the criterion of overweight for Asian people that is recommended by Western Pacific Region of the World Health Organization. We carried out a cross-sectional analysis of the association between the criterion of overweight for ethnic Asian people--body mass indices (BMI) of 23.0-24.9 kg/m(2)--and the presence of obesity-related metabolic disorders among middle-aged Japanese men (n = 974, age range 51-59). The odds ratios (95% confidence interval) of overweight to those with normal weight (BMI < 23.0 kg/m(2)) were 1.61 (1.11-2.33) for the presence of impaired glucose tolerance, 1.95 (1.30-2.93) for hypertension, 2.22 (1.63-3.03) for hypercholesterolemia, 2.83 (2.02-3.97) for hypertriglyceridemia, and 2.06 (1.06-4.00) for hyperuricemia. Overweight was not associated with the presence of type 2 diabetes or with high gamma-glutamyl transferase in the present study (odds ratios: 1.09 and 1.05, respectively). Adjustment for age, rank, and lifestyle factors affected the results only slightly. Based on these results, we conclude that the Asian criterion of overweight appears to be rational in terms of its association with obesity-related metabolic disorders in male personnel of the Japan Self-Defense Forces in their fifties.

Evaluation of inflammation during fixed orthodontic treatment.

PubMed

Bilgic, Fundagul; Akinci Sozer, Ozlem; Ozcan, Oguzhan; Gurpinar, Ahmet Burak; Yilmaz, Hakki; Ay, Yazgi

2016-11-01

The aim of this study was to assess effects of fixed orthodontic therapy on high-sensitivity C-reactive protein (hs-CRP) level, CBC parameters and levels of aspartate aminotransferase (AST) and alanine aminotransferase (ALT), gamma glutamyl transferase (GGT), alkaline phosphatase (ALP), urea, creatinine, sodium (Na), potassium (K), calcium (Ca), total protein (TP), and albumin (Alb). Blood samples (7ml) were drawn at baseline, on days 1 and 7, and three months after placement of braces in the study group, while only one blood sample was drawn at baseline in the control group. Serum hs-CRP levels were measured by nephelometric method. Friedman two-way variance analysis was used to assess values with skewed distribution obtained at baseline, on days 1 and 7, in the third month. Wilcoxon rank sign test was performed if median values were unequal. During measurement periods, there were significant increases in hs-CRP level, WBC count and neutrophil count while a significant decrease in Na level (p<0.05). K level was significantly decreased on the day 1. No significant differences were detected in other biochemical parameters evaluated. Elevation in serum hs-CRP levels and neutrophil: lymphocyte ratio within first 3 months indicates that a systemic immune response develops against therapy in patients undergoing fixed orthodontic therapy. Copyright © 2016 Elsevier Ltd. All rights reserved.

Ginseng, green tea or fibrate: valid options for nonalcoholic steatohepatitis prevention?

PubMed

Miranda-Henriques, Mônica Souza de; Diniz, Margareth de Fátima Formiga de Melo; Araújo, Maria Salete Trigueiro de

2014-01-01

Panax ginseng, Camellia sinensis and bezafibrate were compared for their lipid-lowering, antioxidant and anti-inflammatory properties as potential agents to prevent nonalcoholic fatty liver disease and its progression to nonalcoholic steatohepatitis. Fifty Wistar rats were randomized into five groups: G1 (feed with standard diet); G2 (feed with high-fat diet with 58% of energy from fat); G3 (high-fat diet + standardized Panax ginseng extract at 100 mg/kg/day); G4 (high-fat diet + standardized Camellia sinensis extract at 100 mg/kg/day); and G5 (high-fat diet + bezafibrate at 100 mg/kg/day), given by gavage. The animals were sacrificed eight weeks later and blood was collected for glucose, insulin, cholesterol, triglycerides, AST, ALT, alkaline phosphatase and gamma-glutamyl transferase determinations. The score system for nonalcoholic fatty liver disease was used to analyse the liver samples. High-fat diet resulted in a significant increase in animal body weight, biochemical changes and enzymatic elevations. Steatosis, inflammation and hepatocellular ballooning scores were significant high in this group. The biochemical and histological variables were statistically similar in the bezafibrate group and control group. Treatment with Panax ginseng extract prevented obesity and histological features of nonalcoholic steatohepatitis (steatosis and inflammation) compared to high-fat diet. Camellia sinensis showed a less effective biochemical response, with small reduction in steatosis and inflammation but lower ballooning scores.

Changes of blood biochemistry in the rabbit animal model in atherosclerosis research; a time- or stress-effect

PubMed Central

2011-01-01

Background Rabbits are widely used in biomedical research and especially as animal models in atherosclerosis studies. Blood biochemistry is used to monitor progression of disease, before final evaluation including pathology of arteries and organs. The aim of the present study was to assess the consistency of the biochemical profile of New Zealand White rabbits on standard diet from 3 to 6 months of age, during which they are often used experimentally. Methods and results Eight conventional male 3-month-old New Zealand White rabbits were used. Blood samples were taken at baseline, 1, 2 and 3 months later. Plasma glucose, total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, triacylglycerol concentrations, and alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, gamma glutamyl transferase activities and malondialdehyde were measured. Statistically significant time-related changes were observed in glucose, total cholesterol and triacylglycerol, which were not correlated with aortic lesions at 6 months of age. Similarly, hepatic enzyme activity had significant time-related changes, without a corresponding liver pathology. Conclusions Age progression and stress due to single housing may be the underlying reasons for these biochemistry changes. These early changes, indicative of metabolic alterations, should be taken into account even in short-term lipid/atherosclerosis studies, where age and standard diet are not expected to have an effect on the control group of a study. PMID:21838924

Low Hepatic Tissue Copper in Pediatric Nonalcoholic Fatty Liver Disease.

PubMed

Mendoza, Michael; Caltharp, Shelley; Song, Ming; Collin, Lindsay; Konomi, Juna V; McClain, Craig J; Vos, Miriam B

2017-07-01

Animal models and studies in adults have demonstrated that copper restriction increases severity of liver injury in nonalcoholic fatty liver disease (NAFLD). This has not been studied in children. We aimed to determine if lower tissue copper is associated with increased NAFLD severity in children. This was a retrospective study of pediatric patients who had a liver biopsy including a hepatic copper quantitation. The primary outcome compared hepatic copper concentration in NAFLD versus non-NAFLD. Secondary outcomes compared hepatic copper levels against steatosis, fibrosis, lobular inflammation, balloon degeneration, and NAFLD activity score (NAS). The study analysis included 150 pediatric subjects (102 with NAFLD and 48 non-NAFLD). After adjusting for age, body mass index z score, gamma glutamyl transferase, alanine aminotransferase, and total bilirubin, NAFLD subjects had lower levels of hepatic copper than non-NAFLD (P = 0.005). In addition, tissue copper concentration decreased as steatosis severity increased (P < 0.001). Copper levels were not associated with degree of fibrosis, lobular inflammation, portal inflammation, or balloon degeneration. In this cohort of pediatric subjects with NAFLD, we observed decreased tissue copper levels in subjects with NAFLD when compared with non-NAFLD subjects. In addition, tissue copper levels were lower in subjects with nonalcoholic steatohepatitis, a more severe form of the disease, when compared with steatosis alone. Further studies are needed to explore the relationship between copper levels and NAFLD progression.

Protective Effect of Perindopril on Tumor Progression and Angiogenesis in Animal Model of Breast Cancer.

PubMed

Patel, Snehal S; Nakka, Surender

2017-01-01

Studies have shown that the renin angiotensin system via angiogenesis is involved in tumor development. Therefore, objective of the present study was to examine the effect of perindopril on tumor growth and angiogenesis in animal models of breast cancer. In the present study, the effect of perindopril on tumor development of mammary gland cancer induced by 7,12-dimethylbenz[a]anthracene, mouse tumor xenograft and corneal micropocket model has been investigated. Anti-angiogenic effect by chick yolk sac membrane assay has also been studied. In the present study, it has been found that perindopril produced a significant inhibition of tumor growth, in DMBA induced breast cancer. Treatment also produced significant suppression of cancer biomarkers such as lactate dehydrogenase, gamma glutamyl transferase and inflammatory markers such as C-reactive protein, erythrocyte sedimentation rate. Histopathological analysis also showed that perindopril was able to inhibit tumor development by the inhibition of hyperplastic lesions. Perindopril produced significant inhibition of tumor growth, in a mouse xenograft model and caused inhibition of neovascularization in the corneal micropocket model. In chick yolk sac membrane assay, perindopril showed inhibition of vascular growth and reduced blood vessel formation. Therefore, perindopril is widely used in clinical practice, may represent a neo-adjuvant therapy for treatment of breast cancer. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Isolation and characterization of adult human liver progenitors from ischemic liver tissue derived from therapeutic hepatectomies.

PubMed

Stachelscheid, Harald; Urbaniak, Thomas; Ring, Alexander; Spengler, Berlind; Gerlach, Jörg C; Zeilinger, Katrin

2009-07-01

Recent evidence suggests that progenitor cells in adult tissues and embryonic stem cells share a high resistance to hypoxia and ischemic stress. To study the ischemic resistance of adult liver progenitors, we characterized remaining viable cells in human liver tissue after cold ischemic treatment for 24-168 h, applied to the tissue before cell isolation. In vitro cultures of isolated cells showed a rapid decline of the number of different cell types with increasing ischemia length. After all ischemic periods, liver progenitor-like cells could be observed. The comparably small cells exhibited a low cytoplasm-to-nucleus ratio, formed densely packed colonies, and showed a hepatobiliary marker profile. The cells expressed epithelial cell adhesion molecule, epithelial-specific (CK8/18) and biliary-specific (CK7/19) cytokeratins, albumin, alpha-1-antitrypsin, cytochrome-P450 enzymes, as well as weak levels of hepatocyte nuclear factor-4 and gamma-glutamyl transferase, but not alpha-fetoprotein or Thy-1. In vitro survival and expansion was facilitated by coculture with mouse embryonic fibroblasts. Hepatic progenitor-like cells exhibit a high resistance to ischemic stress and can be isolated from human liver tissue after up to 7 days of ischemia. Ischemic liver tissue from various sources, thought to be unsuitable for cell isolation, may be considered as a prospective source of hepatic progenitor cells.

Gallic acid against hepatocellular carcinoma: An integrated scheme of the potential mechanisms of action from in vivo study.

PubMed

Aglan, Hadeer A; Ahmed, Hanaa H; El-Toumy, Sayed A; Mahmoud, Nadia S

2017-06-01

The global burden of hepatocellular carcinoma is increasing; actually, it is estimated as 750,000 new cases annually. This study was initiated to emphasize the possibility that gallic acid could alleviate hepatocarcinogenesis in vivo. In this study, 40 rats were enrolled and distributed as follows; group 1 was set as negative control, while all of groups 2, 3, and 4 were orally received N-nitrosodiethylamine for hepatocellular carcinoma induction. Group 2 was left untreated, whereas groups 3 and 4 were orally treated with gallic acid and doxorubicin, respectively. The current data indicated that gallic acid administration in hepatocellular carcinoma bearing rats yielded significant decline in serum levels of alpha-fetoprotein, glypican-3, and signal transducer and activator of transcription 3 along with significant enhancement in serum suppressors of cytokine signaling 3 level. Also, gallic acid-treated group displayed significant downregulation in the gene expression levels of hepatic gamma glutamyl transferase and heat shock protein gp96. Intriguingly, treatment with gallic acid remarkably ameliorated the destabilization of liver tissue architecture caused by N-nitrosodiethylamine intoxication as evidenced by histopathological investigation. In conclusion, this study demonstrates that the hepatocarcinogenic effect of N-nitrosodiethylamine can be abrogated by gallic acid supplementation owing to its affinity to regulate signal transducer and activator of transcription 3 signaling pathway through its outstanding bioactivities including antioxidant, anti-inflammatory, apoptotic, and antitumor effects.

Protective effect of lipoic acid on cyclophosphamide-induced testicular toxicity.

PubMed

Selvakumar, Elangovan; Prahalathan, Chidambaram; Sudharsan, Periyasamy Thandavan; Varalakshmi, Palaninathan

2006-05-01

Cyclophosphamide (CP), a widely used anticancer and immunosuppressive drug causes severe testicular toxicity. We investigated the protective effect of lipoic acid in CP-induced testicular toxicity. Two groups of male Wistar rats (140+/-20 g) were administered CP (15 mg/kg body weight, oral gavage) once a week for 10 weeks to induce testicular toxicity; one of these groups received lipoic acid treatment (35 mg/kg body weight, i.p., 24 h prior to CP administration) once a week for 10 weeks. A vehicle treated control and a lipoic acid control groups were also included. The untreated CP exposed rats showed a significant increase in testicular reactive oxygen species (ROS) level, along with a significant decrease in cellular thiol levels. The activities of testicular marker enzymes such as gamma-glutamyl transferase, beta-glucuronidase, acid phosphatase and alkaline phosphatase were increased whereas the activities of sorbitol dehydrogenase and lactate dehydrogenase-X were decreased significantly in the animals treated with CP. In contrast, rats pretreated with lipoic acid showed normal marker enzymic patterns and normal levels of ROS and thiols. Testicular protection by lipoic acid is further substantiated by the normal histologic findings as against shrunken seminiferous tubules with impaired spermatogenesis in the CP administered rats. By the reversal of biochemical and morphological changes towards normalcy, the cytoprotective role of lipoic acid is illuminated in CP-induced testicular toxicity.

Morbidity-mortality and performance evaluation of Brahman calves from in vitro embryo production

PubMed Central

2011-01-01

Background The use of bovine in vitro embryo production (IVP) increases the reproductive potential of genetically superior cows, enabling a larger scale of embryo production when compared with other biotechnologies. However, deleterious effects such as abnormal fetal growth, longer gestation period, increased birth weight, abortion, preterm birth and higher rates of neonatal mortality have been attributed to IVP. The aim of this study was to compare the influence of in vitro embryo production and artificial insemination (AI) on gestation length, complications with birth, birth weight, method of feeding colostrum, passive transfer of immunity, morbidity-mortality, and performance in Brahman calves. Results Whilst gestation length and birth weight were significantly increased in IVP-derived calves, no difference in weaning weight was observed between groups. The passive transfer of immunity (PT), was assessed in IVP (n = 80) and AI (n = 20) groups 24 hours after birth by determination of gamma-glutamyl transferase (GGT) and gammaglobulin activity as well as by quantification of the concentration of total protein in serum. No differences in passive transfer or incidences of dystocia and diseases at weaning were observed between groups. Birth weight, method of feeding colostrum and dystocia were not correlated with PT in either group. Conclusions In this study, in vitro embryo production did not affect the health status, development, or passive transfer of immunity in Brahman calves. PMID:22136315

An efficient model for auxiliary diagnosis of hepatocellular carcinoma based on gene expression programming.

PubMed

Zhang, Li; Chen, Jiasheng; Gao, Chunming; Liu, Chuanmiao; Xu, Kuihua

2018-03-16

Hepatocellular carcinoma (HCC) is a leading cause of cancer-related death worldwide. The early diagnosis of HCC is greatly helpful to achieve long-term disease-free survival. However, HCC is usually difficult to be diagnosed at an early stage. The aim of this study was to create the prediction model to diagnose HCC based on gene expression programming (GEP). GEP is an evolutionary algorithm and a domain-independent problem-solving technique. Clinical data show that six serum biomarkers, including gamma-glutamyl transferase, C-reaction protein, carcinoembryonic antigen, alpha-fetoprotein, carbohydrate antigen 153, and carbohydrate antigen 199, are related to HCC characteristics. In this study, the prediction of HCC was made based on these six biomarkers (195 HCC patients and 215 non-HCC controls) by setting up optimal joint models with GEP. The GEP model discriminated 353 out of 410 subjects, representing a determination coefficient of 86.28% (283/328) and 85.37% (70/82) for training and test sets, respectively. Compared to the results from the support vector machine, the artificial neural network, and the multilayer perceptron, GEP showed a better outcome. The results suggested that GEP modeling was a promising and excellent tool in diagnosis of hepatocellular carcinoma, and it could be widely used in HCC auxiliary diagnosis. Graphical abstract The process to establish an efficient model for auxiliary diagnosis of hepatocellular carcinoma.

Effects of Multivitamin, Multimineral and Phytonutrient Supplementation on Nutrient Status and Biomarkers of Heart Health Risk in a Russian Population: A Randomized, Double Blind, Placebo Controlled Study.

PubMed

Isakov, Vasily A; Bogdanova, Alexandra A; Bessonov, Vladimir V; Sentsova, Tatiana B; Tutelyan, Victor A; Lin, Yumei; Kazlova, Valentina; Hong, Jina; Velliquette, Rodney A

2018-01-25

The primary objective of this clinical study was to evaluate the effect of a dietary multivitamin, multimineral and phytonutrient (VMP) supplement on blood nutrient status and biomarkers of heart health risk in a Russian population. One hundred twenty healthy adults (40-70 years) were recruited for a 56-day (eight-week) randomized, double blind, placebo controlled study with parallel design. Subjects were divided into two groups and received either a VMP or a placebo (PLA) supplement. Blood nutrient levels of β-carotene, α-tocopherol, vitamin C, B6, B12, red blood cell (RBC) folate, Zinc and Selenium were measured at baseline and on Days 28 and 56, and quercetin was measured at baseline and on Day 56. Blood biomarkers of heart health, i.e. homocysteine (Hcy), high-sensitivity C-reactive protein (hs-CRP), oxidized LDL (ox-LDL), gamma-glutamyl transferase (GGT), uric acid and blood lipid profile, were measured at baseline and Day 56. Dietary VMP supplementation for 56 days significantly increased circulating levels of quercetin, vitamin C, RBC folate and partially prevented the decline in vitamin B6 and B12 status. Both serum Hcy and GGT were significantly reduced (-3.97 ± 10.09 µmol/L; -1.68 ± 14.53 U/L, respectively) after VMP supplementation compared to baseline. Dietary VMP supplementation improved the nutrient status and reduced biomarkers of heart health risk in a Russian population.

Examination of the relationships between environmental exposures to volatile organic compounds and biochemical liver tests: application of canonical correlation analysis.

PubMed

Liu, Jing; Drane, Wanzer; Liu, Xuefeng; Wu, Tiejian

2009-02-01

This study was to explore the relationships between personal exposure to 10 volatile organic compounds (VOCs) and biochemical liver tests with the application of canonical correlation analysis. Data from a subsample of the 1999-2000 National Health and Nutrition Examination Survey were used. Serum albumin, total bilirubin (TB), alanine aminotransferase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH), alkaline phosphatase (ALP), and gamma-glutamyl transferase (GGT) served as the outcome variables. Personal exposures to benzene, chloroform, ethylbenzene, tetrachloroethene, toluene, trichloroethene, o-xylene, m-,p-xylene, 1,4-dichlorobenzene, and methyl tert-butyl ether (MTBE) were assessed through the use of passive exposure monitors worn by study participants. The first two canonical correlations were 0.3218 and 0.2575, suggesting a positive correlation mainly between the six VOCs (benzene, ethylbenzene, toluene, o-xylene, m-,p-xylene, and MTBE) and the three biochemical liver tests (albumin, ALP, and GGT) and a positive correlation mainly between the two VOCs (1,4-dichlorobenzene and tetrachloroethene) and the two biochemical liver tests (LDH and TB). Subsequent multiple linear regressions show that exposure to benzene, toluene, or MTBE was associated with serum albumin, while exposure to tetrachloroethene was associated with LDH and total bilirubin. In conclusion, exposure to certain VOCs as a group or individually may influence certain biochemical liver test results in the general population.

The one year exercise and lifestyle intervention program KLAKS: Effects on anthropometric parameters, cardiometabolic risk factors and glycemic control in childhood obesity.

PubMed

Blüher, Susann; Petroff, David; Wagner, Antje; Warich, Katja; Gausche, Ruth; Klemm, Thorsten; Wagner, Mario; Keller, Alexandra

2014-03-01

Regular physical exercise within structured lifestyle programs may improve weight status and minimize metabolic risk factors in childhood obesity. The aim of this study was to evaluate the effect of the one-year combined physical exercise/lifestyle program KLAKS on anthropometric and metabolic parameters and glycemic control in childhood obesity. 142 overweight/obese (BMI>90th percentile) candidates (7-18years) were enrolled, 115 participants completed the program. Anthropometrics and biochemical parameters were obtained at beginning and completion. An oral glucose tolerance test (OGTT) was performed in a subgroup of participants. Course of glucose and insulin levels within OGTT was correlated with several parameters and is reported here for those who completed the program. The mean standard deviation scores (SDS) decreased significantly for BMI, waist circumference, waist-to-height ratio (WHtR) and percentage body fat (all p≤0.01). Improved metabolic risk markers included mean glucose levels within an OGTT at follow-up compared to baseline (p<0.0001) and HbA1c (p=0.05) as well as indications of improvement for gamma-glutamyl-transferase and free fatty acids. The one-year combined exercise/lifestyle program KLAKS significantly improves markers of obesity and glycemic control. Impaired cardiometabolic risk markers, even subclinical, are also favorably influenced by program participation. Copyright © 2014 Elsevier Inc. All rights reserved.

Hepatoprotective Role of Wheatgrass on Alcohol and ΔPUFA-Induced Oxidative Stress in Rats.

PubMed

Durairaj, Varalakshmi; Shakya, Garima; Rajagopalan, Rukkumani

2015-06-01

Alcohol abuse is recognized as the most common cause for the development of various abnormalities including liver disease. Excessive free radicals are generated during the metabolism of ethanol. The ingestion of alcohol along with polyunsaturated fatty acid (PUFA) aggravates the production of free radicals and enhances the oxidative stress. Medicinal plants contain active phytocomponents, which are the principal healthcare resources. We aimed to analyze the effect of wheatgrass extract on alcohol and thermally oxidized PUFA (ΔPUFA) induced oxidative stress in male albino Wistar rats. The levels of marker enzymes gamma-glutamyl transferase (GGT), alkaline phosphatase (ALP), lipid peroxidative markers; thiobarbutric acid reactive substances (TBARS) and lipid hydroperoxides (LH), the levels of enzymatic (catalase [CAT], superoxide dismutase [SOD], glutathione peroxidase [GPx]) and nonenzymatic (reduced glutathione [GSH], vitamin E, vitamin C) antioxidants were analyzed in liver to evaluate the effects of wheatgrass. The levels of TBARS and LH were significantly (p ≤ .05) increased in alcohol + ΔPUFA group, which were found to be reduced on treatment with wheatgrass. The levels of both enzymatic and nonenzymatic antioxidants were significantly (p ≤ .05) decreased in alcohol + ΔPUFA group, which were found to be restored on treatment with wheatgrass. From the results obtained, we conclude that wheatgrass protects the liver against alcohol and ΔPUFA induced oxidative stress.

Immunochemical detection of glycated beta- and gamma-crystallins in lens and their circulating autoantibodies (IgG) in streptozocin induced diabetic rat.

PubMed

Ranjan, Mala; Nayak, Sujatha; Rao, Beedu Sashidhar

2006-09-13

This study used an immunochemical approach aimed to detect the glycated crystallins (beta- and gamma-crystallin) in rat lens and their circulating specific autoantibodies in serum during the course of cataractogenesis. Streptozocin (STZ; 55 mg/kg body mass) induced diabetic male Wistar/NIN rats (2-3 months old) and control nondiabetic rats were used for this study. Plasma glucose, glycated hemoglobin and body weight were evaluated on day zero, and at the interval of every two weeks up to the eighth week of post-injection in both the groups. Other biochemical parameters, such as the levels of nonprotein sulfhydryl (-SH) groups and the activity of gamma-glutamyl transpeptidase (gamma-GT) in lens proteins were also estimated. Cataract progress was monitored by measuring the advanced glycation end product (AGE)-like fluorophores in both intact lens as well as in lens homogenate employing digital based image analysis and spectrofluorimetric methods. Similarly, the polyclonal antibodies specific to beta-glycated-, gamma-glycated-, beta-, and gamma-crystallins were used to determine the concentration of respective immunogens in lens by noncompetitive ELISA and their respective circulating antibodies by antibody capture assay. The profile of glycated lens protein (soluble and insoluble fractions) during the course of cataractogenesis was assessed by the western blot technique. STZ induced diabetic rats showed typical signs of diabetes (hyperglycemia, increased water and food intake with no increase in body weight). Biochemical analysis of total lens protein showed a significant (p = <0.001) decrease in the levels of nonprotein -SH groups. The activity of lenticular gamma-GT in diabetic rats was found to be unaltered as compared to the control group. Digital analysis of intact lens illustrated a positive correlation (r(2)=0.888) with the formation of AGE-like fluorophores during the course of cataractogenesis. A similar trend was also observed in the levels of AGE

The glutathione-S-transferase Mu 1 null genotype modulates ozone-induced airway inflammation in humans*

EPA Science Inventory

Background: The Glutathione-S-Transferase Mu 1 null genotype has been reported to be a risk factor for acute respiratory disease associated with increases in ambient air ozone. Ozone is known to cause an immediate decrease in lung function and increased airway inflammation. Howev...

Dishevelled3 is a novel arginine methyl transferase substrate.

PubMed

Bikkavilli, Rama Kamesh; Avasarala, Sreedevi; Vanscoyk, Michelle; Sechler, Marybeth; Kelley, Nicole; Malbon, Craig C; Winn, Robert A

2012-01-01

Dishevelled, a phosphoprotein scaffold, is a central component in all the Wnt-sensitive signaling pathways. In the present study, we report that Dishevelled is post-translationally modified, both in vitro and in vivo, via arginine methylation. We also show protein arginine methyl transferases 1 and 7 as the key enzymes catalyzing Dishevelled methylation. Interestingly, Wnt3a stimulation of F9 teratocarcinoma cells results in reduced Dishevelled methylation. Similarly, the methylation-deficient mutant of Dishevelled, R271K, displayed spontaneous membrane localization and robust activation of Wnt signaling; suggesting that differential methylation of Dishevelled plays an important role in Wnt signaling. Thus arginine methylation is shown to be an important switch in regulation of Dishevelled function and Wnt signaling.

gamma-Hexachlorocyclohexane (gamma-HCH)

Integrated Risk Information System (IRIS)

gamma - Hexachlorocyclohexane ( gamma - HCH ) ; CASRN 58 - 89 - 9 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Asse

Directed evolution of glutathione transferases towards a selective glutathione-binding site and improved oxidative stability.

PubMed

Axarli, Irine; Muleta, Abdi W; Chronopoulou, Evangelia G; Papageorgiou, Anastassios C; Labrou, Nikolaos E

2017-01-01

Glutathione transferases (GSTs) are a family of detoxification enzymes that catalyze the conjugation of glutathione (GSH) to electrophilic compounds. A library of alpha class GSTs was constructed by DNA shuffling using the DNA encoding the human glutathione transferase A1-1 (hGSTA1-1) and the rat glutathione transferase A1-1 (rGSTA1-1). Activity screening of the library allowed the selection of a chimeric enzyme variant (GSTD4) that displayed high affinity towards GSH and GSH-Sepharose affinity adsorbent, higher k cat /K m and improved thermal stability, compared to the parent enzymes. The crystal structures of the GSTD4 enzyme in free form and in complex with GSH were determined to 1.6Šand 2.3Šresolution, respectively. Analysis of the GSTD4 structure showed subtle conformational changes in the GSH-binding site and in electron-sharing network that may contribute to the increased GSH affinity. The shuffled variant GSTD4 was further optimized for improved oxidative stability employing site-saturation mutagenesis. The Cys112Ser mutation confers optimal oxidative stability and kinetic properties in the GSTD4 enzyme. DNA shuffling allowed the creation of a chimeric enzyme variant with improved properties, compared to the parent enzymes. X-ray crystallography shed light on how recombination of a specific segment from homologous GSTA1-1 together with point mutations gives rise to a new functionally competent enzyme with improved binding, catalytic properties and stability. Such an engineered GST would be useful in biotechnology as affinity tool in affinity chromatography as well as a biocatalytic matrix for the construction of biochips or enzyme biosensors. Copyright © 2016 Elsevier B.V. All rights reserved.

Unidentified Gamma-Ray Sources: Hunting Gamma-Ray Blazars

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

Massaro, F.; D'Abrusco, R.; Tosti, G.

2012-04-02

One of the main scientific objectives of the ongoing Fermi mission is unveiling the nature of the unidentified {gamma}-ray sources (UGSs). Despite the large improvements of Fermi in the localization of {gamma}-ray sources with respect to the past {gamma}-ray missions, about one third of the Fermi-detected objects are still not associated to low energy counterparts. Recently, using the Wide-field Infrared Survey Explorer (WISE) survey, we discovered that blazars, the rarest class of Active Galactic Nuclei and the largest population of {gamma}-ray sources, can be recognized and separated from other extragalactic sources on the basis of their infrared (IR) colors. Basedmore » on this result, we designed an association method for the {gamma}-ray sources to recognize if there is a blazar candidate within the positional uncertainty region of a generic {gamma}-ray source. With this new IR diagnostic tool, we searched for {gamma}-ray blazar candidates associated to the UGS sample of the second Fermi {gamma}-ray catalog (2FGL). We found that our method associates at least one {gamma}-ray blazar candidate as a counterpart each of 156 out of 313 UGSs analyzed. These new low-energy candidates have the same IR properties as the blazars associated to {gamma}-ray sources in the 2FGL catalog.« less

UNIDENTIFIED {gamma}-RAY SOURCES: HUNTING {gamma}-RAY BLAZARS

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

Massaro, F.; Ajello, M.; D'Abrusco, R.

2012-06-10

One of the main scientific objectives of the ongoing Fermi mission is unveiling the nature of unidentified {gamma}-ray sources (UGSs). Despite the major improvements of Fermi in the localization of {gamma}-ray sources with respect to the past {gamma}-ray missions, about one-third of the Fermi-detected objects are still not associated with low-energy counterparts. Recently, using the Wide-field Infrared Survey Explorer survey, we discovered that blazars, the rarest class of active galactic nuclei and the largest population of {gamma}-ray sources, can be recognized and separated from other extragalactic sources on the basis of their infrared (IR) colors. Based on this result, wemore » designed an association method for the {gamma}-ray sources to recognize if there is a blazar candidate within the positional uncertainty region of a generic {gamma}-ray source. With this new IR diagnostic tool, we searched for {gamma}-ray blazar candidates associated with the UGS sample of the second Fermi {gamma}-ray LAT catalog (2FGL). We found that our method associates at least one {gamma}-ray blazar candidate as a counterpart to each of 156 out of 313 UGSs analyzed. These new low-energy candidates have the same IR properties as the blazars associated with {gamma}-ray sources in the 2FGL catalog.« less

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

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

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

2014-01-21

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

Growth kinetics of gamma-prime precipitates in a directionally solidified eutectic, gamma/gamma-prime-delta

NASA Technical Reports Server (NTRS)

Tewari, S. N.

1976-01-01

A directionally solidified eutectic alloy (DSEA), of those viewed as potential candidates for the next generation of aircraft gas turbine blade materials, is studied for the gamma-prime growth kinetics, in the system Ni-Nb-Cr-Al, specifically: Ni-20 w/o Nb-6 w/o Cr-2.5 w/o Al gamma/gamma-prime-delta DSEA. Heat treatment, polishing and etching, and preparation for electron micrography are described, and the size distribution of gamma-prime phase following various anneals is plotted, along with gamma-prime growth kinetics in this specific DSEA, and the cube of gamma-prime particle size vs anneal time. Activation energies and coarsening kinetics are studied.

The neutron-gamma Feynman variance to mean approach: Gamma detection and total neutron-gamma detection (theory and practice)

NASA Astrophysics Data System (ADS)

Chernikova, Dina; Axell, Kåre; Avdic, Senada; Pázsit, Imre; Nordlund, Anders; Allard, Stefan

2015-05-01

Two versions of the neutron-gamma variance to mean (Feynman-alpha method or Feynman-Y function) formula for either gamma detection only or total neutron-gamma detection, respectively, are derived and compared in this paper. The new formulas have particular importance for detectors of either gamma photons or detectors sensitive to both neutron and gamma radiation. If applied to a plastic or liquid scintillation detector, the total neutron-gamma detection Feynman-Y expression corresponds to a situation where no discrimination is made between neutrons and gamma particles. The gamma variance to mean formulas are useful when a detector of only gamma radiation is used or when working with a combined neutron-gamma detector at high count rates. The theoretical derivation is based on the Chapman-Kolmogorov equation with the inclusion of general reactions and corresponding intensities for neutrons and gammas, but with the inclusion of prompt reactions only. A one energy group approximation is considered. The comparison of the two different theories is made by using reaction intensities obtained in MCNPX simulations with a simplified geometry for two scintillation detectors and a 252Cf-source. In addition, the variance to mean ratios, neutron, gamma and total neutron-gamma are evaluated experimentally for a weak 252Cf neutron-gamma source, a 137Cs random gamma source and a 22Na correlated gamma source. Due to the focus being on the possibility of using neutron-gamma variance to mean theories for both reactor and safeguards applications, we limited the present study to the general analytical expressions for Feynman-alpha formulas.

Partial purification and characterization of a mannosyl transferase involved in O -linked mannosylation of glycoproteins in Candida albicans.

PubMed

Arroyo-Flores, Blanca L; Calvo-Méndez, Carlos; Flores-Carreón, Arturo; López-Romero, Everardo

2004-04-01

Incubation of a mixed membrane fraction of C. albicans with the nonionic detergents Nonidet P-40 or Lubrol solubilized a fraction that catalyzed the transfer of mannose either from endogenously generated or exogenously added dolichol-P-[14C]Man onto endogenous protein acceptors. The protein mannosyl transferase solubilized with Nonidet P-40 was partially purified by a single step of preparative nondenaturing electrophoresis and some of its properties were investigated. Although transfer activity occurred in the absence of exogenous mannose acceptors and thus depended on acceptor proteins isolated along with the enzyme, addition of the protein fraction obtained after chemical de-mannosylation of glycoproteins synthesized in vitro stimulated mannoprotein labeling in a concentration-dependent manner. Other de-mannosylated glycoproteins, such as yeast invertase or glycoproteins extracted from C. albicans, failed to increase the amount of labeled mannoproteins. Mannosyl transfer activity was not influenced by common metal ions such as Mg(2+), Mn(2+) and Ca(2+), but it was stimulated up to 3-fold by EDTA. Common phosphoglycerides such as phosphatidylglycerol and, to a lower extent, phosphatidylinositol and phosphatidylcholine enhanced transfer activity. Interestingly, coupled transfer activity between dolichol phosphate mannose synthase, i.e., the enzyme responsible for Dol-P-Man synthesis, and protein mannosyl transferase could be reconstituted in vitro from the partially purified transferases, indicating that this process can occur in the absence of cell membranes.

Quantification of butyryl CoA:acetate CoA-transferase genes reveals different butyrate production capacity in individuals according to diet and age.

PubMed

Hippe, Berit; Zwielehner, Jutta; Liszt, Kathrin; Lassl, Cornelia; Unger, Frank; Haslberger, Alexander G

2011-03-01

The gastrointestinal microbiota produces short-chain fatty acids, especially butyrate, which affect colonic health, immune function and epigenetic regulation. To assess the effects of nutrition and aging on the production of butyrate, the butyryl-CoA:acetate CoA-transferase gene and population shifts of Clostridium clusters lV and XlVa, the main butyrate producers, were analysed. Faecal samples of young healthy omnivores (24 ± 2.5 years), vegetarians (26 ± 5 years) and elderly (86 ± 8 years) omnivores were evaluated. Diet and lifestyle were assessed in questionnaire-based interviews. The elderly had significantly fewer copies of the butyryl-CoA:acetate CoA-transferase gene than young omnivores (P=0.014), while vegetarians showed the highest number of copies (P=0.048). The thermal denaturation of the butyryl-CoA:acetate CoA-transferase gene variant melting curve related to Roseburia/Eubacterium rectale spp. was significantly more variable in the vegetarians than in the elderly. The Clostridium cluster XIVa was more abundant in vegetarians (P=0.049) and in omnivores (P<0.01) than in the elderly group. Gastrointestinal microbiota of the elderly is characterized by decreased butyrate production capacity, reflecting increased risk of degenerative diseases. These results suggest that the butyryl-CoA:acetate CoA-transferase gene is a valuable marker for gastrointestinal microbiota function. © 2011 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

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

NASA Astrophysics Data System (ADS)

Neta, Raimunda Nonata Fortes Carvalho; Torres, Audalio Rebelo

2017-11-01

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

Characterization of spermidine hydroxycinnamoyl transferases from eggplant (Solanum melongena L.) and its wild relative Solanum richardii Dunal

USDA-ARS?s Scientific Manuscript database

Eggplant produces a variety of hydroxycinnamic acid amides (HCAAs) that play an important role in plant development and adaptation to environmental changes. However, the HCAA pathway remains largely uncharacterized in Solanaceae. In this study, a spermidine hydroxycinnamoyl transferase (SHT) from eg...

Infectious mononucleosis and hepatic function

PubMed Central

Zhang, Li; Zhou, Pingping; Meng, Zhaowei; Pang, Chongjie; Gong, Lu; Zhang, Qing; Jia, Qiyu; Song, Kun

2018-01-01

Abnormal hepatic function is common in infectious mononucleosis (IM). However, it remains unknown why increased transferase levels are more common than bilirubin abnormalities in IM. The current study aimed to investigate these associations in the Chinese population. A total of 95 patients with IM (47 males and 48 females) were enrolled in the current study, as well as 95 healthy controls. Patients were sorted by sex. A receiver operating characteristic (ROC) curve was used to determine cut-off values for IM diagnosis and prediction. Crude and adjusted odds ratios (OR) for IM were analyzed using binary logistic regression. It was determined that alanine aminotransferase (ALT), aspartate aminotransferase (AST) and γ-glutamyl transferase (GGT) levels were significantly higher in patients with IM compared with controls; however, total bilirubin (TB) levels were significantly lower in patients with IM. ROCs demonstrated that, if ALT, AST and GGT concentrations were higher than, or if TB was lower than, cut-off values, they were predictive of IM. Binary logistic regression identified that the risk of IM in patients exhibiting high levels of transferases was significantly increased, particularly in males. Crude ORs in ALT quartile 4 were 21.667 and 10.111 for males and females, respectively and adjusted ORs were 38.054 and 9.882, respectively. A significant IM risk of IM was evident in patients with low bilirubin levels and females appeared to be particularly susceptible. For example, crude ORs in quartile 1 were 8.229 and 8.257 for males and females, respectively and adjusted ORs were 8.883 and 10.048, respectively. Therefore, the current study identified a positive association between transferase levels and IM and a negative association between TB and IM. Therefore, the results of the current study indicate that high transferases are suggestive of IM, particularly in males, whereas low TB is suggestive for IM, particularly in females. PMID:29456696

Very high-energy gamma rays from gamma-ray bursts.

PubMed

Chadwick, Paula M

2007-05-15

Very high-energy (VHE) gamma-ray astronomy has undergone a transformation in the last few years, with telescopes of unprecedented sensitivity having greatly expanded the source catalogue. Such progress makes the detection of a gamma-ray burst at the highest energies much more likely than previously. This paper describes the facilities currently operating and their chances for detecting gamma-ray bursts, and reviews predictions for VHE gamma-ray emission from gamma-ray bursts. Results to date are summarized.

Chromatographic methods for determination of S-substituted cysteine derivatives--a comparative study.

PubMed

Kubec, Roman; Dadáková, Eva

2009-10-09

A novel HPLC method for determination of a wide variety of S-substituted cysteine derivatives in Allium species has been developed and validated. This method allows simultaneous separation and quantification of S-alk(en)ylcysteine S-oxides, gamma-glutamyl-S-alk(en)ylcysteines and gamma-glutamyl-S-alk(en)ylcysteine S-oxides in a single run. The procedure is based on extraction of these amino acids and dipeptides by methanol, their derivatization by dansyl chloride and subsequent separation by reversed phase HPLC. The main advantages of the new method are simplicity, excellent stability of derivatives, high sensitivity, specificity and the ability to simultaneously analyze the whole range of S-substituted cysteine derivatives. This method was critically compared with other chromatographic procedures used for quantification of S-substituted cysteine derivatives, namely with two other HPLC methods (derivatization by o-phthaldialdehyde/tert-butylthiol and fluorenylmethyl chloroformate), and with determination by gas chromatography or capillary electrophoresis. Major advantages and drawbacks of these analytical procedures are discussed. Employing these various chromatographic methods, the content and relative proportions of individual S-substituted cysteine derivatives were determined in four most frequently consumed alliaceous vegetables (garlic, onion, shallot, and leek).

Evaluation of a controlled drinking minimal intervention for problem drinkers in general practice (the DRAMS scheme)

PubMed Central

Heather, Nick; Campion, Peter D.; Neville, Ronald G.; Maccabe, David

1987-01-01

Sixteen general practitioners participated in a controlled trial of the Scottish Health Education Group's DRAMS (drinking reasonably and moderately with self-control) scheme. The scheme was evaluated by randomly assigning 104 heavy or problem drinkers to three groups – a group participating in the DRAMS scheme (n = 34), a group given simple advice only (n = 32) and a non-intervention control group (n = 38). Six month follow-up information was obtained for 91 subjects (87.5% of initial sample). There were no significant differences between the groups in reduction in alcohol consumption, but patients in the DRAMS group showed a significantly greater reduction in a logarithmic measure of serum gamma-glutamyl-transpeptidase than patients in the group receiving advice only. Only 14 patients in the DRAMS group completed the full DRAMS procedure. For the sample as a whole, there was a significant reduction in alcohol consumption, a significant improvement on a measure of physical health and well-being, and significant reductions in the logarithmic measure of serum gamma-glutamyl transpeptidase and in mean corpuscular volume. The implications of these findings for future research into controlled drinking minimal interventions in general practice are discussed. PMID:3448228

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

PubMed Central

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

2008-01-01

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

Proinflammatory and anti-inflammatory cytokine balance in gasoline exhaust induced pulmonary injury in mice.

PubMed

Sureshkumar, Veerapandian; Paul, Bholanath; Uthirappan, Mani; Pandey, Renu; Sahu, Anand Prakash; Lal, Kewal; Prasad, Arun Kumar; Srivastava, Suresh; Saxena, Ashok; Mathur, Neeraj; Gupta, Yogendra Kumar

2005-03-01

Proinflammatory and anti-inflammatory cytokine balance and associated changes in pulmonary bronchoalveolar lavage fluid (BALF) of unleaded gasoline exhaust (GE) exposed mice were investigated. Animals were exposed to GE (1 L/min of GE mixed with 14 L/min of compressed air) using a flow-past, nose-only, dynamic inhalation exposure chamber for different durations (7, 14, and 21 days). The particulate content of the GE was found to be 0.635, +/-0.10 mg PM/m3. Elevated levels of tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) were observed in BALF of GE-exposed mice, but interleukin 1beta(IL-1beta) and the anti-inflammatory cytokine interleukin-10 (IL-10) remained unaffected. GE induced higher activities of alkaline phosphatase (ALP), gamma-glutamyl transferase (gammaGT), and lactate dehydrogenase (LDH) in the BALF, indicating Type II alveolar epithelial cell injury, Clara-cell injury, and general toxicity, respectively. Total protein in the BALF increased after 14 and 21 days of exposure, indicating enhanced alveolar-capillary permeability. However, the difference in the mean was found statistically insignificant in comparison to the compressed air control. Total cell count in the BALF of GE-exposed mice ranged between 0.898 and 0.813x10(6) cells/ml, whereas the compressed air control showed 0.65x10(6) cells/mL. The histopathological changes in GE-exposed lung includes perivascular, and peribronchiolar cuffing of mononuclear cells, migration of polymorphonuclear cells in the alveolar septa, alveolar thickening, and mild alveolar edematous changes indicating inflammation. The shift in pro- and anti-inflammatory cytokine balance and elevation of the pulmonary marker enzymes indicate toxic insult of GE. This study will help in our understanding of the mechanism of pulmonary injury by GE in the light of cytokine profiles, pulmonary marker enzymes, and lung architecture.

The insect repellent DEET (N,N-diethyl-3-methylbenzamide) increases the synthesis of glutathione S-transferase in cultured mosquito cells.

PubMed

Hellestad, Vanessa J; Witthuhn, Bruce A; Fallon, Ann M

2011-04-01

DEET (N,N-diethyl-3-methylbenzamide) is the active ingredient used in many commonly used insect repellents, but its mode of action remains poorly understood. Efforts to identify properties that could lead to the development of more effective active ingredients have distinguished among DEET's repellent, deterrent, and insecticidal activities. We used an Aedes albopictus mosquito cell line to evaluate DEET's toxicological properties in the absence of sensory input mediated by the olfactory system. When cells were treated with DEET and labeled with [(35)S]methionine/cysteine, a single 25-kDa protein was induced, relative to other proteins, on SDS-polyacrylamide gels. The 25-kDa band from DEET-treated cells was enriched in peptides corresponding to glutathione S-transferase D10 and/or theta in the Aedes aegypti genome. Consistent with the increased expression of the labeled protein, DEET-treated cells had increased glutathione S-transferase activity, and the radiolabeled band bound to Sepharose 4B containing reduced glutathione. By analyzing partial tryptic digests, we established that DEET induces the homolog of A. aegypti glutathione S-transferase, class theta, corresponding to protein XP_001658009.1 in the NCBI database. This specific effect of DEET at the subcellular level suggests that DEET induces physiological responses that extend beyond recognition by the peripheral olfactory system.

Nonprotein amino acids from seeds of Cycas circinalis and Phaseolus vulgaris.

PubMed

Li, C J; Brownson, D M; Mabry, T J; Perera, C; Bell, E A

1996-05-01

Our chemical studies on Cycas circinalis seeds from Guam has provided two new nonprotein amino acids, N-(3'-one-5'-methyl)-hexylalanine and leucine betaine. N-methylisoleucine, previously reported as a component of naturally occurring peptides, has been isolated as a free amino acid from the seeds of Phaseolus vulgaris (pinto bean), together with S-methylcysteine, pipecolic acid and a dipeptide, gamma-glutamyl-leucine.

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

EPA Science Inventory

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

p-aminophenol nephrotoxicity: biosynthesis of toxic glutathione conjugates.

PubMed

Klos, C; Koob, M; Kramer, C; Dekant, W

1992-07-01

p-Aminophenol causes necrosis of the pars recta of the proximal tubules in rats, and its nephrotoxicity may be due to glutathione-dependent bioactivation reactions. We have investigated the hepatic metabolism of p-aminophenol in Wistar rats and the cytotoxicity of formed glutathione S-conjugates in rat renal epithelial cells. After ip application of p-aminophenol (100 mg/kg), the following metabolites were identified in rat bile: 4-amino-2-(glutathion-S-yl)phenol, 4-amino-3-(glutathion-S-yl)-phenol, 4-amino-2,5-bis(glutathion-S-yl)phenol, 4-amino-2,3,5(or 6)-tris(glutathion-S-yl)phenol, an aminophenol conjugate (likely a sulfate or glucuronide), acetaminophen glucuronide, and 3-(glutathion-S-yl)acetaminophen. 4-Amino-3-(glutathion-S-yl)phenol, 4-amino-2,5-bis(glutathion-S-yl)phenol, and 4-amino-2,3,5(or 6)-tris(glutathion-S-yl)phenol induced a dose- and time-dependent loss of cell viability in rat kidney cortical cells. Cell killing was significantly reduced by inhibition of gamma-glutamyl transpeptidase with Acivicin. p-Aminophenol was also toxic to renal epithelial cells. Coincubation of p-aminophenol with tetraethylammonium bromide, a competitive inhibitor of the organic cation transporter, and with SKF-525A, an inhibitor of cytochrome P450, protected cells from p-aminophenol-induced toxicity. p-Aminophenol would thus be accumulated in the kidney mainly by organic cation transport systems, which are concentrated in the S-1 segment of the proximal tubule. However, p-aminophenol toxicity in vivo is directed toward the S-2 and S-3 segments, which are rich in gamma-glutamyl transpeptidase. These results and the observation that biliary cannulation and glutathione depletion reduce p-aminophenol nephrotoxicity suggest that the biosynthesis of toxic glutathione conjugates is responsible for p-aminophenol nephrotoxicity in vivo. The aminophenol glutathione S-conjugates formed induce p-aminophenol nephrotoxicity by a pathway dependent on gamma-glutamyl transpeptidase.

Glucose-induced expression of MIP-1 genes requires O-GlcNAc transferase in monocytes

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

Chikanishi, Toshihiro; ERATO, Japan Science and Technology Agency, 4-1-8 Honcho, Kawaguchi-shi, Saitama 332-0012; Fujiki, Ryoji

2010-04-16

O-glycosylation has emerged as an important modification of nuclear proteins, and it appears to be involved in gene regulation. Recently, we have shown that one of the histone methyl transferases (MLL5) is activated through O-glycosylation by O-GlcNAc transferase (OGT). Addition of this monosaccharide is essential for forming a functional complex. However, in spite of the abundance of OGT in the nucleus, the impact of nuclear O-glycosylation by OGT remains largely unclear. To address this issue, the present study was undertaken to test the impact of nuclear O-glycosylation in a monocytic cell line, THP-1. Using a cytokine array, MIP-1{alpha} and -1{beta}more » genes were found to be regulated by nuclear O-glycosylation. Biochemical purification of the OGT interactants from THP-1 revealed that OGT is an associating partner for distinct co-regulatory complexes. OGT recruitment and protein O-glycosylation were observed at the MIP-1{alpha} gene promoter; however, the known OGT partner (HCF-1) was absent when the MIP-1{alpha} gene promoter was not activated. From these findings, we suggest that OGT could be a co-regulatory subunit shared by functionally distinct complexes supporting epigenetic regulation.« less

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

PubMed Central

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

2011-01-01

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

Gamma-sky.net: Portal to the gamma-ray sky

NASA Astrophysics Data System (ADS)

Voruganti, Arjun; Deil, Christoph; Donath, Axel; King, Johannes

2017-01-01

http://gamma-sky.net is a novel interactive website designed for exploring the gamma-ray sky. The Map View portion of the site is powered by the Aladin Lite sky atlas, providing a scalable survey image tesselated onto a three-dimensional sphere. The map allows for interactive pan and zoom navigation as well as search queries by sky position or object name. The default image overlay shows the gamma-ray sky observed by the Fermi-LAT gamma-ray space telescope. Other survey images (e.g. Planck microwave images in low/high frequency bands, ROSAT X-ray image) are available for comparison with the gamma-ray data. Sources from major gamma-ray source catalogs of interest (Fermi-LAT 2FHL, 3FGL and a TeV source catalog) are overlaid over the sky map as markers. Clicking on a given source shows basic information in a popup, and detailed pages for every source are available via the Catalog View component of the website, including information such as source classification, spectrum and light-curve plots, and literature references. We intend for gamma-sky.net to be applicable for both professional astronomers as well as the general public. The website started in early June 2016 and is being developed as an open-source, open data project on GitHub (https://github.com/gammapy/gamma-sky). We plan to extend it to display more gamma-ray and multi-wavelength data. Feedback and contributions are very welcome!

Staphylococcus aureus HemX Modulates Glutamyl-tRNA Reductase Abundance To Regulate Heme Biosynthesis

PubMed Central

Choby, Jacob E.; Grunenwald, Caroline M.; Celis, Arianna I.; Gerdes, Svetlana Y.; DuBois, Jennifer L.

2018-01-01

ABSTRACT Staphylococcus aureus is responsible for a significant amount of devastating disease. Its ability to colonize the host and cause infection is supported by a variety of proteins that are dependent on the cofactor heme. Heme is a porphyrin used broadly across kingdoms and is synthesized de novo from common cellular precursors and iron. While heme is critical to bacterial physiology, it is also toxic in high concentrations, requiring that organisms encode regulatory processes to control heme homeostasis. In this work, we describe a posttranscriptional regulatory strategy in S. aureus heme biosynthesis. The first committed enzyme in the S. aureus heme biosynthetic pathway, glutamyl-tRNA reductase (GtrR), is regulated by heme abundance and the integral membrane protein HemX. GtrR abundance increases dramatically in response to heme deficiency, suggesting a mechanism by which S. aureus responds to the need to increase heme synthesis. Additionally, HemX is required to maintain low levels of GtrR in heme-proficient cells, and inactivation of hemX leads to increased heme synthesis. Excess heme synthesis in a ΔhemX mutant activates the staphylococcal heme stress response, suggesting that regulation of heme synthesis is critical to reduce self-imposed heme toxicity. Analysis of diverse organisms indicates that HemX is widely conserved among heme-synthesizing bacteria, suggesting that HemX is a common factor involved in the regulation of GtrR abundance. Together, this work demonstrates that S. aureus regulates heme synthesis by modulating GtrR abundance in response to heme deficiency and through the activity of the broadly conserved HemX. PMID:29437922

Phosphorus amendment reduces hepatic and renal oxidative stress in mallards ingesting lead-contaminated sediments

USGS Publications Warehouse

Hoffman, D.J.; Heinz, G.H.; Audet, D.J.

2006-01-01

Lead poisoning of waterfowl has been reported for decades in the Coeur d'Alene River Basin (CDARB) in Idaho as a result of the ingestion of lead-contaminated sediments. This study was conducted to determine whether the addition of phosphoric acid to CDARB sediments would reduce the bioavailability and toxicity of lead to the liver and kidney of mallards (Anas platyrhynchos). Mallards received diets containing 12% clean sediment (controls) or 12% sediment from three different CDARB sites containing 4520, 5390, or 6990 ug/g lead (dry weight) with or without phosphoric acid amendment. Liver and kidney lead concentrations were significantly higher in all CDARB treatment groups and ranged from geometric mean values of 18.2 (liver) and 28.7 (kidney) for the first 2 sites to 22.5 (liver) and 45.6 (kidney) ug/g (wet weight) for the third site. With amendments all liver lead concentrations were reduced 36 to 55%, and all kidney lead concentrations were lowered 54 to 73%. Unamended CDARB sediment from the third site resulted in the following hepatic effects: over 1.6-fold elevation of liver glutathione (reduced form; GSH) concentration, higher GSH S-transferase and oxidized glutathione (GSSG) reductase activities, and lower protein-bound thiols (PBSH) concentration. Renal effects included higher kidney GSH concentrations for all CDARB sites, with over 2.1-fold higher for the third site. Resulting kidney GSSG to GSH ratios were lower at two sites. At the third site, gamma-glutamyl transferase (GGT) activity was elevated, and lipid peroxidation as thiobarbituric acid-reactive substances (TBARS) was 1.7-fold greater. Amendment restored all hepatic variables as well as the renal variables TBARS and GGT so they did not differ from controls. Although amendments of phosphorus substantially reduced the bioavailability of lead and some of the adverse effects, lead concentrations in the tissues of mallards fed the amended sediments were still above those considered to be harmful to

Hepatoprotective Potential of Some Local Medicinal Plants against 2-Acetylaminoflourene-Induced Damage in Rat

PubMed Central

Adetutu, Adewale; Olorunnisola, Olubukola S.

2013-01-01

The in vivo micronucleus assay was used to examine the anticlastogenic effects of crude extracts of Bridelia ferruginea, Vernonia amygdalina, Tridax procumbens, Ocimum gratissimum, and Lawsonia inermis in Wistar albino rats. Extracts of doses of 100 mg/kg body weight were given to rats in five groups for seven consecutive days followed by a single dose of 2-AAF (0.5 mmol/kg body weight). The rats were sacrificed after 24 hours and their bone marrow smears were prepared on glass slides stained with Giemsa. The micronucleated polychromatic erythrocyte cells (mPCEs) were thereafter recorded. The hepatoprotective effects of the plant extracts against 2-AAF-induced liver toxicity in rats were evaluated by monitoring the levels of alkaline phosphatase (ALP), gamma glutamyl transferase (GGT), and histopathological analysis. The results of the 2-AAF-induced liver toxicity experiments showed that rats treated with the plant extracts (100 mg/kg) showed a significant decrease in mPCEs as compared with the positive control. The rats treated with the plant extracts did not show any significant change in the concentration of ALP and GGT in comparison with the negative control group whereas the 2-AAF group showed a significant increase (P < 0.05) in these parameters. Some of the leaf extracts also showed protective effects against histopathological alterations. This study suggests that the leaf extracts have hepatoprotective potential, thereby justifying their ethnopharmacological uses. PMID:24163694

Hepatoprotective Potential of Some Local Medicinal Plants against 2-Acetylaminoflourene-Induced Damage in Rat.

PubMed

Adetutu, Adewale; Olorunnisola, Olubukola S

2013-01-01

The in vivo micronucleus assay was used to examine the anticlastogenic effects of crude extracts of Bridelia ferruginea, Vernonia amygdalina, Tridax procumbens, Ocimum gratissimum, and Lawsonia inermis in Wistar albino rats. Extracts of doses of 100 mg/kg body weight were given to rats in five groups for seven consecutive days followed by a single dose of 2-AAF (0.5 mmol/kg body weight). The rats were sacrificed after 24 hours and their bone marrow smears were prepared on glass slides stained with Giemsa. The micronucleated polychromatic erythrocyte cells (mPCEs) were thereafter recorded. The hepatoprotective effects of the plant extracts against 2-AAF-induced liver toxicity in rats were evaluated by monitoring the levels of alkaline phosphatase (ALP), gamma glutamyl transferase (GGT), and histopathological analysis. The results of the 2-AAF-induced liver toxicity experiments showed that rats treated with the plant extracts (100 mg/kg) showed a significant decrease in mPCEs as compared with the positive control. The rats treated with the plant extracts did not show any significant change in the concentration of ALP and GGT in comparison with the negative control group whereas the 2-AAF group showed a significant increase (P < 0.05) in these parameters. Some of the leaf extracts also showed protective effects against histopathological alterations. This study suggests that the leaf extracts have hepatoprotective potential, thereby justifying their ethnopharmacological uses.

Protective effect of Piper betle leaf extract against cadmium-induced oxidative stress and hepatic dysfunction in rats

PubMed Central

Milton Prabu, S.; Muthumani, M.; Shagirtha, K.

2012-01-01

The present study was undertaken to examine the attenuative effect of Piper betle leaf extract (PBE) against cadmium (Cd) induced oxidative hepatic dysfunction in the liver of rats. Pre-oral supplementation of PBE (200 mg/kg BW) treated rats showed the protective efficacy against Cd induced hepatic oxidative stress. Oral administration of Cd (5 mg/kg BW) for four weeks to rats significantly (P > 0.05) elevated the level of serum hepatic markers such as serum aspartate transaminase (AST), serum alanine transaminase (ALT), alkaline phosphatase (ALP), lactate dehydrogenase (LDH), gamma-glutamyl transpeptidase (GGT), bilirubin (TBRNs), oxidative stress markers viz., thiobarbituric acid reactive substances (TBARS), lipid hydroperoxides (LOOH), protein carbonyls (PC) and conjugated dienes (CD) and significantly (P > 0.05) reduced the enzymatic antioxidants viz., superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione S-transferase (GST), glutathione reductase (GR) and glucose-6-phosphate dehydrogenase (G6PD) and non-enzymatic antioxidants Viz., reduced glutathione (GSH), total sulfhydryls (TSH), vitamin C and vitamin E in the liver. Pre-oral supplementation of PBE (200 mg/kg BW) in Cd intoxicated rats, the altered biochemical indices and pathological changes were recovered significantly (P > 0.05) which showed ameliorative effect of PBE against Cd induced hepatic oxidative stress. From the above findings, we suggested that the pre-administration of P. betle leaf extract exhibited remarkable protective effects against cadmium-induced oxidative hepatic injury in rats. PMID:23961183

Protective effect of Piper betle leaf extract against cadmium-induced oxidative stress and hepatic dysfunction in rats.

PubMed

Milton Prabu, S; Muthumani, M; Shagirtha, K

2012-04-01

The present study was undertaken to examine the attenuative effect of Piper betle leaf extract (PBE) against cadmium (Cd) induced oxidative hepatic dysfunction in the liver of rats. Pre-oral supplementation of PBE (200 mg/kg BW) treated rats showed the protective efficacy against Cd induced hepatic oxidative stress. Oral administration of Cd (5 mg/kg BW) for four weeks to rats significantly (P > 0.05) elevated the level of serum hepatic markers such as serum aspartate transaminase (AST), serum alanine transaminase (ALT), alkaline phosphatase (ALP), lactate dehydrogenase (LDH), gamma-glutamyl transpeptidase (GGT), bilirubin (TBRNs), oxidative stress markers viz., thiobarbituric acid reactive substances (TBARS), lipid hydroperoxides (LOOH), protein carbonyls (PC) and conjugated dienes (CD) and significantly (P > 0.05) reduced the enzymatic antioxidants viz., superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione S-transferase (GST), glutathione reductase (GR) and glucose-6-phosphate dehydrogenase (G6PD) and non-enzymatic antioxidants Viz., reduced glutathione (GSH), total sulfhydryls (TSH), vitamin C and vitamin E in the liver. Pre-oral supplementation of PBE (200 mg/kg BW) in Cd intoxicated rats, the altered biochemical indices and pathological changes were recovered significantly (P > 0.05) which showed ameliorative effect of PBE against Cd induced hepatic oxidative stress. From the above findings, we suggested that the pre-administration of P. betle leaf extract exhibited remarkable protective effects against cadmium-induced oxidative hepatic injury in rats.

[Hepatobiliary System Diseases as the Predictors of Psoriasis Progression].

PubMed

Smirnova, S V; Barilo, A A; Smolnikova, M V

2016-01-01

To assess the state of the hepatobiliary system in psoriasis andpsoriatic arthritis in order to establish a causal relationship and to identify clinical and functional predictors of psoriatic disease progression. The study includedpatients with extensive psoriasis vulgaris (n = 175) aged 18 to 66 years old and healthy donors (n = 30), matched by sex and age: Group 1--patients with psoriasis (PS, n = 77), group 2--patients with psoriatic arthritis (PsA, n = 98), group 3--control. The evaluation of functional state of the hepatobiliary system was performed by the analysis of the clinical and anamnestic data and by the laboratory-instrumental methods. We identified predictors of psoriasis: triggers (stress and nutritionalfactor), increased total bilirubin, aspartate aminotransferase, alkaline phosphatase, gamma-glutamyl transferase, eosinophilia, giardiasis, carriers of hepatitis C virus, ductal changes andfocal leisons in the liver, thickening of the walls of the gallbladder detected by ultrasound. Predictors ofpsoriatic arthritis: age over 50 years, dyspeptic complaints, the presence of hepatobiliary system diseases, the positive right hypochondrium syndrome, the clinical symptoms of chronic cholecystitis, excess body weight, high levels of bilirubin, cholesterol and low density lipoprotein, hepatomegaly, non-alcoholic fatty liver disease. High activity of hepatocytes cytolysis, cholestasis, inflammation, metabolic disorders let us considerpsoriatic arthritis as a severe clinical stage psoriatic disease when the hepatobiliary system, in turn, is one of the main target organs in systemic psoriatic process. Non-alcoholic fatty liver disease and chronic cholecystitis are predictors of psoriatic disease progression.

Toxicological effects of cationic nanobubbles on the liver and kidneys: biomarkers for predicting the risk.

PubMed

Pan, Tai-Long; Wang, Pei-Wen; Al-Suwayeh, Saleh A; Huang, Yi-Ju; Fang, Jia-You

2012-11-01

Nanobubbles with acoustical activity are used as both diagnostic and therapeutic carriers for detecting and treating diseases. We aimed to prepare nanobubbles and assess toxic responses to them in the liver and kidneys. The cytotoxicity of nanobubbles was determined by examining the viability of liver (HepG2) and kidney (293T) cell lines after a 24-h treatment at various concentrations (0.01-2%). Toxic effects of different formulations were compared by determining functional markers such as γ-glutamyl transferase (γ-GT) and blood urea nitrogen (BUN) after intravenous administration of nanobubbles. Cationic nanobubbles caused concentration-dependent cytotoxicity against cultured cells with a more significant effect in the liver than in the kidneys. A significant reduction of viability was revealed at a concentration as low as 0.1%. Cational systems with soyaethyl morpholinium ethosulfate (SME) exhibited the greatest γ-GT level at 6-fold higher than the control. Immunohistochemistry detected liver fibrosis and inflammation with nanobubbles treatment, especially SME-containing ones at higher doses. According to plasma proteomic profiles, gelsolin and fetuin-B were significantly downregulated 3-fold in the high-dose SME-treated group. Transthyretin decreased by 6-fold in this group. The fibrinogen gamma chain expression was highly elevated. The results suggest that these protein biomarkers are sensitive for assessing the risk of nanobubble exposure. This study is the first to systematically evaluate the possible toxicity of nanobubbles in the liver and kidneys. Copyright © 2012 Elsevier Ltd. All rights reserved.

Colic caused by Panicum maximum toxicosis in equidae in northern Brazil.

PubMed

Cerqueira, Valíria D; Riet-Correa, Gabriela; Barbosa, José D; Duarte, Marcos D; Oliveira, Carlos M C; de Oliveira, Carlos A; Tokarnia, Carlos; Lee, Stephen T; Riet-Correa, Franklin

2009-11-01

In the Amazon region of northern Brazil, Panicum maximum cultivars Mombaça, Tanzânia, and Massai cause severe colic and death in horses and mules. The disease occurs in the rainy season, when sprouting pastures are grazed by equidae. In the 8 separate disease outbreaks studied, a total of 52 out of 153 equidae were affected, including 19 that died (10 mules and 9 horses). Clinical signs were colic and abdominal dilatation, with a clinical manifestation period of 12 hr to 4 days. Serum activities of gamma-glutamyl transferase and aspartate aminotransferase were within reference intervals; however, serum urea nitrogen and creatinine concentrations were occasionally elevated. The primary gross and histologic lesions were observed in the digestive system. The stomach, small intestine, and large intestine had severe hemorrhages and occasional mucosal erosions and ulcerations. Ulceration and hemorrhage of the urinary bladder were rarely observed. Histologic examination revealed diffuse lymphoplasmacytic gastritis and enteritis with severe congestion, hemorrhage, and occasional epithelial necrosis and ulceration. Lymphocellular necrosis was occasionally observed within gut-associated lymphoid tissue. Tubular nephrosis occurred in some animals. Degeneration and occasional necrosis of bile duct epithelial cells and degeneration of hepatocytes were observed in the liver. Toxic pastures were negative for diosgenin- and yamogenin-based saponins, and oxalate concentrations were within reference intervals for the species. The toxin or toxins causing disease and the reason for the toxicity of the plant in the northern region are unknown.

Vital capacity and selected metabolic diseases in middle-aged Japanese men

PubMed Central

Sakuta, Hidenari; Suzuki, Takashi; Yasuda, Hiroko; Ito, Teizo

2006-01-01

OBJECTIVE To elucidate the association between vital capacity and the presence of selected metabolic diseases in middle-aged Japanese men. METHODS A cross-sectional analysis of the associations among forced vital capacity (FVC), static vital capacity as a percentage of that predicted (%VC) and the presence of metabolic diseases was performed. RESULTS In a univariate linear regression analysis, FVC and %VC were inversely associated with poor vegetable intake, cigarette smoking and body mass index, but not with physical activity or ethanol consumption. In a logistic regression analysis adjusted for lifestyle factors, body mass index and age, the odds ratios for the presence of metabolic disease per 0.54 L (1 SD) decrease in FVC were 1.24 (95% CI 1.03 to 1.50) for type II diabetes, 1.21 (95% CI 1.02 to 1.42) for hypertension, 1.34 (95% CI 1.11 to 1.63) for hypertriglyceridemia, 1.23 (95% CI 1.03 to 1.46) for high gamma-glutamyl transferase levels and 1.63 (95% CI 1.10 to 2.41) for an episode of cardiovascular disease. FVC did not correlate with hyperhomocysteinemia, hypercholesterolemia or high white blood cell count. Similar results were also obtained for the association between %VC and metabolic diseases. CONCLUSIONS A decrease in FVC or %VC was associated with the presence of some metabolic diseases. The association may partly explain the reported association between low FVC and cardiovascular disease. PMID:16550264

Protective Effect of Ethanolic Extract of Grape Pomace against the Adverse Effects of Cypermethrin on Weanling Female Rats

PubMed Central

Mossa, Abdel-Tawab H.; Ibrahim, Faten M.; Mohafrash, Samia M. M.; Abou Baker, Doha H.; El Gengaihi, Souad

2015-01-01

The adverse effect of cypermethrin on the liver and kidney of weanling female rats and the protective effect of ethanolic extract of grape pomace were investigated in the present study. Weanling female rats were given cypermethrin oral at a dose of 25 mg kg−1 body weight for 28 consecutive days. An additional two Cyp-trated groups received extract at a dose of 100 and 200 mg kg−1 body weight, respectively, throughout the experimental duration. Three groups more served as extract and control groups. Administration of Cyp resulted in a significant increase in serum marker enzymes, for example, aminotransferases (AST and ALT), alkaline phosphatase (ALP), and gamma-glutamyl transferase (GGT), and increases the level of urea nitrogen and creatinine. In contrast, Cyp caused significant decrease in levels of total protein and albumin and caused histopathological alterations in liver and kidneys of female rats. Coadministration of the extract to Cyp-treated female rats restored most of these biochemical parameters to within normal levels especially at high dose of extract. However, extract administration to Cyp-treated rats resulted in overall improvement in liver and kidney damage. This study demonstrated the adverse biohistological effects of Cyp on the liver and kidney of weanling female rats. The grape pomace extract administration prevented the toxic effect of Cyp on the above serum parameters. The present study concludes that grape pomace extract has significant antioxidant and hepatorenal protective activity. PMID:26265923

[Use of fish oil lipid emulsions in hospitalized patients under 18 years old with abnormal results in liver tests associated with total parental nutrition].

PubMed

Giraldo Villa, Adriana; Henao Roldan, Catherine; García Loboguerrero, Fanny; Martínez Volkmar, María Isabel; Contreras Ramírez, Mónica María; Ruiz Navas, Patricia

2014-04-01

Prolonged Total Parental Nutrition (TPN) is associated with life-threatening complications in the pediatric population, being cholestasis one of the most important ones. The source of fatty acids, the amount of phytosterols and the dose of lipids in the nutritional support, have been linked to the development of this complication. To describe the behavior of liver function tests in pediatric patients with TPN where lipid based omega 3 fatty acids (OmegavenR) were used. A retrospective research was made in a population of children under 18 years old where omega 3 fatty acids were used for a minimum of 8 days. Patients were initially classified into two groups: cholestasis and abnormal liver tests. Levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), total bilirubin (TB), direct bilirubin (DB) gamma glutamyl transferase (GGT) and alkaline phosphatase (AP) before and after treatment with OmegavenR was evaluated. 33 patients met the inclusion criteria. At the end of treatment with OmegavenR, 82.4% of patients who initially presented cholestasis showed resolution or improvement. The group of patients with abnormal liver tests 18.8% progressed to cholestasis. Our study suggests that the use of OmegavenR in pediatric patients with TPN and DB ≥ 2 mg/dL, seem to reverse or improve cholestasis while in patients with abnormal liver tests we still don't have clear effect. Copyright AULA MEDICA EDICIONES 2014. Published by AULA MEDICA. All rights reserved.

Influence of Fasciola hepatica on Serum Biochemical Parameters and Vascular and Biliary System of Sheep Liver

PubMed Central

Hodžić, A; Zuko, A; Avdić, R; Alić, A; Omeragić, J; Jažić, A

2013-01-01

Background The aim of this study was to evaluate the functional capacity of the liver based on the activity of specific enzymes and bilirubin in serum and also to investigate the influence of mechanical and toxic effects of Fasciola hepatica on the structures of the blood vessels and biliary tract in the sheep liver. Methods Blood samples and liver of 63 indigenous sheep of Pramenka breed, slaughtered in the period from March to December 2009 were used. Based on parasitological findings in the liver, all animals were divided into two groups: control (n = 34) and infected group (n = 29). For investigation and description of pathological changes in sheep liver, naturally infected with F. hepatica, corrosion cast technique was used. Results Biochemical analysis of tested parameters showed a significant elevation (P≤0.05) of serum gamma-glutamyl transferase (GGT), total bilirubin (TBIL) and direct bilirubin (DBIL) in infected sheep group comparing with the control group. No significant differences were observed for activity of aspartate aminotranferase (AST) between groups. Vascular and biliary systems of the liver were found to be affected. Conclusion Results of biochemical analysis are consistent with pathological findings and measuring of tested parameters could be used in early diagnosis of sheep fasciolosis and to test the effectiveness of anthelmintic therapy. Corrosion cast technique is very useful for investigation of pathological changes and neoangiogenesis of vascular and biliary system in sheep liver, caused by mechanical and toxic effects of F. hepatica. PMID:23682266

Comparison of Biological Responses in Rats Under Various Cigarette Smoke Exposure Conditions

PubMed Central

Tsuji, Hiroyuki; Fujimoto, Hitoshi; Matsuura, Daiki; Nishino, Tomoki; Lee, K Monica; Yoshimura, Hiroyuki

2013-01-01

A variety of exposure regimens of cigarette smoke have been used in animal models of lung diseases. In this study, we compared biological responses of smoke exposure in rats, using different smoke concentrations (wet total particulate matter [WTPM]), daily exposure durations, and total days of exposure. As a range-finding acute study, we first compared pulmonary responses between SD and F344 strains after a single nose-only exposure to mainstream cigarette smoke or LPS. Secondly, F344 rats were exposed to cigarette smoke for 2 or 13 weeks under the comparable daily exposure dose (WTPM concentration x daily exposure duration; according to Haber’s rule) but at a different WTPM concentration or daily exposure duration. Blood carboxylhemoglobin was increased linearly to the WTPM concentration, while urinary nicotine plus cotinine value was higher for the longer daily exposure than the corresponding shorter exposure groups. Gamma glutamyl transferase activity in bronchoalveolar lavage fluid (BALF) was increased dose dependently after 2 and 13 weeks of cigarette smoke exposure, while the neutrophil content in BALF was not increased notably. Smoke-exposed groups showed reduced body weight gain and increased relative lung and heart weights. While BALF parameters and the relative lung weights suggest pulmonary responses, histopathological examination showed epithelial lesions mainly in the upper respiratory organs (nose and larynx). Collectively, the results indicate that, under the employed study design, the equivalent daily exposure dose (exposure concentration x duration) induces equivalent pulmonary responses in rats. PMID:23914058

Serum ischemia modified albumin is a possible new marker of oxidative stress in phenylketonuria.

PubMed

Keshavarzi, Fatemeh; Rastegar, Mohsen; Vessal, Mahmood; Rafiei Dehbidi, Gholamreza; Khorsand, Marjan; Ganjkarimi, Amir Hossein; Takhshid, Mohammad Ali

2018-06-01

The role of oxidative stress in the pathogenesis of phenylketonuria (PKU)-associated disorders has been implicated. Ischemia modified albumin (IMA) is a modified form of serum albumin, which is produced under the conditions of oxidative stress. The aim of this study was to measure the serum level of IMA in the PKU patients and to investigate its ability in predicting the status of oxidative stress in these patients. Fifty treated-PKU patients and fifty age- and sex-matched healthy subjects were included in the study. The blood samples were obtained and the serum level of phenylalanine (Phe) was measured using reverse phase HPLC method. The levels of IMA, malondialdehyde (MDA), gamma-glutamyl transferase (GGT) activity, and uric acid (UA) were determined using colorimetric methods. The levels of serum Phe, IMA, and MDA were significantly higher (p < 0.001) and the level of UA (p < 0.05) was lower in the PKU patients compared to control group. Serum IMA level was positively correlated with MDA (r = 0.585, p < 0.001) and UA (r = 0.6, p < 0.001). An inverse relationship was observed between the serum level of IMA and Phe (r = - 0.410, p < 0. 01). Results of the present study suggest that serum IMA level could be used as a novel marker for the evaluation of oxidative stress in the PKU patients.

Protective effects of Nano-elemental selenium against chromium-vi-induced oxidative stress in broiler liver.

PubMed

Xueting, L; Rehman, M U; Zhang, H; Tian, X; Wu, X; Shixue; Mehmood, K; Zhou, D

2018-01-01

The valuable role of selenium in mitigation of oxidative stress and heavy metal toxicity is well-known. Thus, the aim of the current study on broiler chickens was to examine whether nano elemental selenium (Nano-Se) supplementation can reduce the effects of chromium VI (K2Cr2O7) toxicity. For this purpose, a total of 150, one-day-old broiler chickens were allotted to five groups with three replicates: control group (standard diet), poisoned group (K2Cr2O7 via drinking water), protection group (K2Cr2O7 + Nano- Se), cure group (K2Cr2O7 for initial 2 weeks and then Nano-Se), and prevention group (opposite to the cure group). The broilers were detected by the activities of marker enzymes and oxidative stress markers including, aspartate aminotransferase (AST), alanine transaminase (ALT), gamma-glutamyl transferase (GGT) and superoxide dismutase (SOD), glutathione peroxidase (GSH-px), malondialdehyde (MDA), respectively. The (K2Cr2O7 administration caused histopathological damage in the liver of the chickens. Moreover, changes in serum biochemical indicators and oxidative stress parameters were also observed. Nano-Se supplementation increased the levels of GSH-px but reduced the activities of SOD, MDA, GGT, ALT and AST in the experimental groups (P less than 0.05). Our results showed that Nano-Se plays a protective role by preventing the oxidative stress induced by the chromium VI in broiler chickens.

Evaluation of linalool, a natural antimicrobial and insecticidal essential oil from basil: effects on poultry.

PubMed

Beier, Ross C; Byrd, J Allen; Kubena, Leon F; Hume, Michael E; McReynolds, Jackson L; Anderson, Robin C; Nisbet, David J

2014-02-01

Linalool is a natural plant-product used in perfumes, cosmetics, and flavoring agents. Linalool has proven antimicrobial and insect-repellent properties, which indicate it might be useful for control of enteropathogens or insect pests in poultry production. However, there are no published reports that linalool may be safely administered to or tolerated by chickens. Linalool was added to the diets of day-of-hatch chicks, and they were fed linalool-supplemented diets for 3 wk. We studied the effects of linalool on serum chemistry, gross pathology, feed conversion, and relative liver weights. Linalool had a dramatic negative dose-dependent effect on feed conversion at concentrations in the feed exceeding 2% linalool, but not on gross pathology. Liver weights were significantly increased in the 5% linalool-treated birds. There was a statistical effect on blood glucose, but this parameter remained below the cut-offs for elevated serum glucose, and the result is likely of no biological significance. Linalool caused serum aspartate aminotransferase (AST) levels to increase, but it did not increase serum gamma-glutamyl transferase levels. The linalool effect on AST was dose-dependent, but in linalool doses between 0.1 and 2% of the feed, AST was not elevated beyond normal parameters. Linalool at 2% or less may be safely added to chicken feed. We suggest future studies to evaluate the addition of linalool to the litter, where it may be used as an antimicrobial or an insect repellent or to produce a calming effect.

Evaluation of the Olympus AU-510 analyser.

PubMed

Farré, C; Velasco, J; Ramón, F

1991-01-01

The selective multitest Olympus AU-510 analyser was evaluated according to the recommendations of the Comision de Instrumentacion de la Sociedad Española de Quimica Clinica and the European Committee for Clinical Laboratory Standards. The evaluation was carried out in two stages: an examination of the analytical units and then an evaluation in routine work conditions. The operational characteristics of the system were also studied.THE FIRST STAGE INCLUDED A PHOTOMETRIC STUDY: dependent on the absorbance, the inaccuracy varies between +0.5% to -0.6% at 405 nm and from -5.6% to 10.6% at 340 nm; the imprecision ranges between -0.22% and 0.56% at 405 nm and between 0.09% and 2.74% at 340 nm. Linearity was acceptable, apart from a very low absorbance for NADH at 340 nm; and the imprecision of the serum sample pipetter was satisfactory.TWELVE SERUM ANALYTES WERE STUDIED UNDER ROUTINE CONDITIONS: glucose, urea urate, cholesterol, triglycerides, total bilirubin, creatinine, phosphate, iron, aspartate aminotransferase, alanine aminotransferase and gamma-glutamyl transferase.The within-run imprecision (CV%) ranged from 0.67% for phosphate to 2.89% for iron and the between-run imprecision from 0.97% for total bilirubin to 7.06% for iron. There was no carryover in a study of the serum sample pipetter. Carry-over studies with the reagent and sample pipetters shows some cross contamination in the iron assay.

Effects of Multivitamin, Multimineral and Phytonutrient Supplementation on Nutrient Status and Biomarkers of Heart Health Risk in a Russian Population: A Randomized, Double Blind, Placebo Controlled Study

PubMed Central

Bogdanova, Alexandra A.; Bessonov, Vladimir V.; Sentsova, Tatiana B.; Tutelyan, Victor A.; Lin, Yumei; Kazlova, Valentina; Velliquette, Rodney A.

2018-01-01

The primary objective of this clinical study was to evaluate the effect of a dietary multivitamin, multimineral and phytonutrient (VMP) supplement on blood nutrient status and biomarkers of heart health risk in a Russian population. One hundred twenty healthy adults (40–70 years) were recruited for a 56-day (eight-week) randomized, double blind, placebo controlled study with parallel design. Subjects were divided into two groups and received either a VMP or a placebo (PLA) supplement. Blood nutrient levels of β-carotene, α-tocopherol, vitamin C, B6, B12, red blood cell (RBC) folate, Zinc and Selenium were measured at baseline and on Days 28 and 56, and quercetin was measured at baseline and on Day 56. Blood biomarkers of heart health, i.e. homocysteine (Hcy), high-sensitivity C-reactive protein (hs-CRP), oxidized LDL (ox-LDL), gamma-glutamyl transferase (GGT), uric acid and blood lipid profile, were measured at baseline and Day 56. Dietary VMP supplementation for 56 days significantly increased circulating levels of quercetin, vitamin C, RBC folate and partially prevented the decline in vitamin B6 and B12 status. Both serum Hcy and GGT were significantly reduced (−3.97 ± 10.09 µmol/L; −1.68 ± 14.53 U/L, respectively) after VMP supplementation compared to baseline. Dietary VMP supplementation improved the nutrient status and reduced biomarkers of heart health risk in a Russian population. PMID:29370120

Impact of the ovarian cycle and pregnancy on plasma chemistry values in ewes

PubMed Central

Zywicki, Micaela E.; Blohowiak, Sharon E.; Magness, Ronald R.; Segar, Jeffrey L.; Kling, Pamela J.

2018-01-01

Normative data for plasma chemistry values in pregnant and non-pregnant reproductive age ewes are scant. Availability of data would aid monitoring of ewe health for both research and veterinary medicine. We determined specific plasma chemistry 95% confidence reference intervals (RIs) in non-pregnant and pregnant ewes. Mixed Western-breed ewes were grouped based on phase of ovarian cycle: luteal (n = 15), follicular (n = 17), or late-gestation pregnant (n = 102). Plasma samples were collected for analysis on a commercial biochemical analyzer. For RIs, chemistry panels for the 3 groups of ewes included nutrients and metabolites (glucose, triglycerides, cholesterol, urea, creatinine, total protein, albumin, and bilirubin), enzymes (lactate dehydrogenase, aspartate transaminase, gamma-glutamyl transferase, alanine aminotransferase, and alkaline phosphatase [ALP]), and micronutrients (calcium, phosphorus, iron, sodium, potassium, and chloride). Sample chemistry values for glucose and total protein in pregnant ewes were lower than in follicular ewes; cholesterol was lower in pregnant and luteal ewes than in follicular ewes. In addition, total bilirubin in pregnant ewes differed from that in luteal ewes, and that in follicular ewes also differed from luteal ewes. ALP in pregnant ewes was higher than other groups; phosphorus in pregnant ewes was lower than in luteal ewes. Iron was higher in pregnant ewes than in luteal ewes, with iron in luteal ewes lower than in follicular ewes. These data provide clinical RIs comparing pregnant and non-pregnant ewes for use in monitoring ewe health in both human research and veterinary medicine. PMID:29291683

Impact of the ovarian cycle and pregnancy on plasma chemistry values in ewes.

PubMed

Zywicki, Micaela E; Blohowiak, Sharon E; Magness, Ronald R; Segar, Jeffrey L; Kling, Pamela J

2018-03-01

Normative data for plasma chemistry values in pregnant and non-pregnant reproductive age ewes are scant. Availability of data would aid monitoring of ewe health for both research and veterinary medicine. We determined specific plasma chemistry 95% confidence reference intervals (RIs) in non-pregnant and pregnant ewes. Mixed Western-breed ewes were grouped based on phase of ovarian cycle: luteal ( n = 15), follicular ( n = 17), or late-gestation pregnant ( n = 102). Plasma samples were collected for analysis on a commercial biochemical analyzer. For RIs, chemistry panels for the 3 groups of ewes included nutrients and metabolites (glucose, triglycerides, cholesterol, urea, creatinine, total protein, albumin, and bilirubin), enzymes (lactate dehydrogenase, aspartate transaminase, gamma-glutamyl transferase, alanine aminotransferase, and alkaline phosphatase [ALP]), and micronutrients (calcium, phosphorus, iron, sodium, potassium, and chloride). Sample chemistry values for glucose and total protein in pregnant ewes were lower than in follicular ewes; cholesterol was lower in pregnant and luteal ewes than in follicular ewes. In addition, total bilirubin in pregnant ewes differed from that in luteal ewes, and that in follicular ewes also differed from luteal ewes. ALP in pregnant ewes was higher than other groups; phosphorus in pregnant ewes was lower than in luteal ewes. Iron was higher in pregnant ewes than in luteal ewes, with iron in luteal ewes lower than in follicular ewes. These data provide clinical RIs comparing pregnant and non-pregnant ewes for use in monitoring ewe health in both human research and veterinary medicine.

Chemical Composition of Golden Berry Leaves Against Hepato-renal Fibrosis.

PubMed

Khalaf-Allah, Abd El-Rahman M; El-Gengaihi, Souad E; Hamed, Manal A; Zahran, Hanan G; Mohammed, Mona A

2016-01-01

The role of Physalis peruviana (golden berry) as functional food against hepato-renal fibrosis induced by carbon tetrachloride (CCl4) was evaluated. The chemical composition of leaves referred the presence of withanolides and flavonoids. Two compounds, ursolic acid and lupeol, were isolated and their structures were elucidated by different spectral analysis techniques. The biological evaluation was conducted on different animal groups; control rats, control orally treated with plant extract (500 mg/kg body weight twice a week for six consecutive weeks), CCl4 (0.5 ml/kg body weight diluted to 1:9 (v/v) in olive oil and injected intraperitoneally) group, CCl4 treated with plant extract and CCl4 treated with silymarin as a reference herbal drug. The evaluation was done through measuring oxidative stress markers; malondialdehyde (MDA), superoxide dismutase (SOD) and nitric oxide (NO). Liver function indices; aspartate and alanine aminotransferases (AST & ALT), alkaline phosphatase (ALP), gamma glutamyl transferase (GGT), bilirubin and total hepatic protein were also estimated. Kidney disorder biomarkers; creatinine, urea and serum protein were also evaluated. The results revealed plant safety and decrease in NO, MDA, IgG, ALP, tissue protein, bilirubin, creatinine and urea levels. Increase in SOD, AST, ALT, GGT and serum protein levels were observed. Improvement in liver and kidney histopathological architectures were also seen. In conclusion, Physalis peruviana recorded a significant protective role in liver and kidney against fibrosis. Further studies are needed to evaluate its isolated compounds and its use in pharmacological applications and clinical uses.

Zea mays, Stigma maydis prevents and extenuates acetaminophen-perturbed oxidative onslaughts in rat hepatocytes.

PubMed

Saheed, Sabiu; Frans Hendrik, O'Neill; Tom, Ashafa Anofi Omotayo

2016-11-01

Zea mays L. (Poaceae) Stigma maydis is an underutilized product of corn cultivation finding therapeutic applications in oxidative stress-related disorders. This study investigated its aqueous extract against acetaminophen (APAP)-perturbed oxidative insults in rat hepatocytes. Hepatotoxic rats were orally pre- and post-treated with the extract (at 200 and 400 mg/kg body weight) and vitamin C (200 mg/kg body weight), respectively, for 14 days. Liver function, antioxidative and histological analyses were thereafter evaluated. The APAP-induced marked (p < 0.05) increases in the activities of alkaline phosphatase, alanine aminotransferase, aspartate aminotransferase, gamma glutamyl transferase and the concentrations of bilirubin, oxidized glutathione, protein carbonyls, malondialdehyde, conjugated dienes, lipid hydroperoxides and fragmented DNA were dose-dependently extenuated in the extract-treated animals. The extract also significantly (p < 0.05) improved the reduced activities of superoxide dismutase, catalase, glutathione reductase and glutathione peroxidase as well as total protein, albumin and glutathione concentrations in the hepatotoxic rats. These improvements may be attributed to the bioactive constituents as revealed by the gas chromatography-mass spectrometric chromatogram of the extract. The observed effects compared favourably with vitamin C and are informative of hepatoprotective and antioxidative attributes of the extract and were further supported by the histological analysis. The data from the present findings suggest that Stigma maydis aqueous extract is capable of preventing and ameliorating APAP-mediated oxidative hepatic damage via enhancement of antioxidant defence systems.

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

PubMed Central

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

2015-01-01

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

Phosphoethanolamine Transferase LptA in Haemophilus ducreyi Modifies Lipid A and Contributes to Human Defensin Resistance In Vitro.

PubMed

Trombley, Michael P; Post, Deborah M B; Rinker, Sherri D; Reinders, Lorri M; Fortney, Kate R; Zwickl, Beth W; Janowicz, Diane M; Baye, Fitsum M; Katz, Barry P; Spinola, Stanley M; Bauer, Margaret E

2015-01-01

Haemophilus ducreyi resists the cytotoxic effects of human antimicrobial peptides (APs), including α-defensins, β-defensins, and the cathelicidin LL-37. Resistance to LL-37, mediated by the sensitive to antimicrobial peptide (Sap) transporter, is required for H. ducreyi virulence in humans. Cationic APs are attracted to the negatively charged bacterial cell surface. In other gram-negative bacteria, modification of lipopolysaccharide or lipooligosaccharide (LOS) by the addition of positively charged moieties, such as phosphoethanolamine (PEA), confers AP resistance by means of electrostatic repulsion. H. ducreyi LOS has PEA modifications at two sites, and we identified three genes (lptA, ptdA, and ptdB) in H. ducreyi with homology to a family of bacterial PEA transferases. We generated non-polar, unmarked mutants with deletions in one, two, or all three putative PEA transferase genes. The triple mutant was significantly more susceptible to both α- and β-defensins; complementation of all three genes restored parental levels of AP resistance. Deletion of all three PEA transferase genes also resulted in a significant increase in the negativity of the mutant cell surface. Mass spectrometric analysis revealed that LptA was required for PEA modification of lipid A; PtdA and PtdB did not affect PEA modification of LOS. In human inoculation experiments, the triple mutant was as virulent as its parent strain. While this is the first identified mechanism of resistance to α-defensins in H. ducreyi, our in vivo data suggest that resistance to cathelicidin LL-37 may be more important than defensin resistance to H. ducreyi pathogenesis.

Resonance production in. gamma gamma. collisions

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

Renard, F.M.

1983-04-01

The processes ..gamma gamma.. ..-->.. hadrons can be depicted as follows. One photon creates a q anti q pair which starts to evolve; the other photon can either (A) make its own q anti q pair and the (q anti q q anti q) system continue to evolve or (B) interact with the quarks of the first pair and lead to a modified (q anti q) system in interaction with C = +1 quantum numbers. A review of the recent theoretical activity concerning resonance production and related problems is given under the following headings: hadronic C = +1 spectroscopy (qmore » anti q, qq anti q anti q, q anti q g, gg, ggg bound states and mixing effects); exclusive ..gamma gamma.. processes (generalities, unitarized Born method, VDM and QCD); total cross section (soft and hard contributions); q/sup 2/ dependence of soft processes (soft/hard separation, 1/sup +- +/ resonances); and polarization effects. (WHK)« less

Tumor necrosis factor alpha induces gamma-glutamyltransferase expression via nuclear factor-kappaB in cooperation with Sp1.

PubMed

Reuter, Simone; Schnekenburger, Michael; Cristofanon, Silvia; Buck, Isabelle; Teiten, Marie-Hélène; Daubeuf, Sandrine; Eifes, Serge; Dicato, Mario; Aggarwal, Bharat B; Visvikis, Athanase; Diederich, Marc

2009-02-01

Gamma-glutamyltransferase (GGT) cleaves the gamma-glutamyl moiety of glutathione (GSH), an endogenous antioxidant, and is involved in mercapturic acid metabolism and in cancer drug resistance when overexpressed. Moreover, GGT converts leukotriene (LT) C4 into LTD4 implicated in various inflammatory pathologies. So far the effect of inflammatory stimuli on regulation of GGT expression and activity remained to be addressed. We found that the proinflammatory cytokine tumor necrosis factor alpha (TNFalpha) induced GGT promoter transactivation, mRNA and protein synthesis, as well as enzymatic activity. Remicade, a clinically used anti-TNFalpha antibody, small interfering RNA (siRNA) against p50 and p65 nuclear factor-kappaB (NF-kappaB) isoforms, curcumin, a well characterized natural NF-kappaB inhibitor, as well as a dominant negative inhibitor of kappaB alpha (IkappaBalpha), prevented GGT activation at various levels, illustrating the involvement of this signaling pathway in TNFalpha-induced stimulation. Over-expression of receptor of TNFalpha-1 (TNFR1), TNFR-associated factor-2 (TRAF2), TNFR-1 associated death domain (TRADD), dominant negative (DN) IkappaBalpha or NF-kappaB p65 further confirmed GGT promoter activation via NF-kappaB. Linker insertion mutagenesis of 536 bp of the proximal GGT promoter revealed NF-kappaB and Sp1 binding sites at -110 and -78 relative to the transcription start site, responsible for basal GGT transcription. Mutation of the NF-kappaB site located at -110 additionally inhibited TNFalpha-induced promoter induction. Chromatin immunoprecipitation (ChIP) assays confirmed mutagenesis results and further demonstrated that TNFalpha treatment induced in vivo binding of both NF-kappaB and Sp1, explaining increased GGT expression, and led to RNA polymerase II recruitment under inflammatory conditions.

Human γ-Glutamyl Transpeptidase 1: STRUCTURES OF THE FREE ENZYME, INHIBITOR-BOUND TETRAHEDRAL TRANSITION STATES, AND GLUTAMATE-BOUND ENZYME REVEAL NOVEL MOVEMENT WITHIN THE ACTIVE SITE DURING CATALYSIS.

PubMed

Terzyan, Simon S; Burgett, Anthony W G; Heroux, Annie; Smith, Clyde A; Mooers, Blaine H M; Hanigan, Marie H

2015-07-10

γ-Glutamyl transpeptidase 1 (GGT1) is a cell surface, N-terminal nucleophile hydrolase that cleaves glutathione and other γ-glutamyl compounds. GGT1 expression is essential in cysteine homeostasis, and its induction has been implicated in the pathology of asthma, reperfusion injury, and cancer. In this study, we report four new crystal structures of human GGT1 (hGGT1) that show conformational changes within the active site as the enzyme progresses from the free enzyme to inhibitor-bound tetrahedral transition states and finally to the glutamate-bound structure prior to the release of this final product of the reaction. The structure of the apoenzyme shows flexibility within the active site. The serine-borate-bound hGGT1 crystal structure demonstrates that serine-borate occupies the active site of the enzyme, resulting in an enzyme-inhibitor complex that replicates the enzyme's tetrahedral intermediate/transition state. The structure of GGsTop-bound hGGT1 reveals its interactions with the enzyme and why neutral phosphonate diesters are more potent inhibitors than monoanionic phosphonates. These structures are the first structures for any eukaryotic GGT that include a molecule in the active site covalently bound to the catalytic Thr-381. The glutamate-bound structure shows the conformation of the enzyme prior to release of the final product and reveals novel information regarding the displacement of the main chain atoms that form the oxyanion hole and movement of the lid loop region when the active site is occupied. These data provide new insights into the mechanism of hGGT1-catalyzed reactions and will be invaluable in the development of new classes of hGGT1 inhibitors for therapeutic use. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

Influence of esterified-glucomannan on performance and organ morphology, serum biochemistry and haematology in broilers exposed to individual and combined mycotoxicosis (aflatoxin, ochratoxin and T-2 toxin).

PubMed

Raju, M V; Devegowda, G

2000-12-01

1. A study was conducted to evaluate the individual and combined effects of aflatoxin B1 (AF), ochratoxin A (OA) and T-2 toxin (T-2) on performance, organ morphology serum biochemistry and haematology of broiler chickens and the efficacy of esterified-glucomannan (E-GM), a cell wall derivative of Saccharomyces cerevisiae1026 in their counteraction. 2. Two dietary inclusion rates of AF (0 and 0.3 mg/kg), OA (0 and 2 mg/kg), T-2 (0 and 3 mg/kg) and E-GM (0 and 1 g/kg) were tested in a 2 x 2 x 2 x 2 factorial manner on a total of 960 broiler chickens from 1 to 35 d of age in an open sided deep litter pen house. 3. Body weight and food intake were depressed by all the mycotoxins, OA being the most toxic during early life. 4. Weights of kidney and adrenals were increased by AF and OA. Liver weight was increased by AF (17.8%), while OA increased gizzard weight (14.6%) and reduced bone ash content (8.1%). T-2 toxin showed no effect on these variables. 5. Serum cholesterol content was decreased and activity of serum gamma glutamyl transferase (GGT) was increased by AF and OA while serum protein content was decreased by AF. These effects were more pronounced at 21 d than at 35 d of age. Inconsistent responses were seen in the other variables: blood urea nitrogen (BUN) content, activities of serum alanine amino transferase and aspertate amino transferase. Blood haemoglobin content was depressed by AF and T-2, whereas blood coagulation time was prolonged by OA. 6. Significant interactions were observed between any 2 toxins for their additive effects on body weight, food intake, bone ash content and serum GGT activity at 21 d. Conversely, antagonistic interactions were observed among any 2 of the toxins for their effects on variables such as serum protein and serum cholesterol content. Simultaneous feeding of all 3 mycotoxins did not show increased toxicity above that seen with any 2. 7. Esterified-glucomannan increased body weight (2.26%) and food intake (1.6%), decreased

The Drosophila protein palmitoylome: Characterizing palmitoyl-thioesterases and DHHC palmitoyl-transferases

PubMed Central

Bannan, Barbra A.; Van Etten, Jamie; Kohler, John A.; Tsoi, Yui; Hansen, Nicole M.; Sigmon, Stacey; Fowler, Elizabeth; Buff, Haley; Williams, Tiffany S.; Ault, Jeffrey G.; Glaser, Robert L.; Korey, Christopher A.

2010-01-01

Palmitoylation is the post-translational addition of a palmitate moiety to a cysteine residue through a covalent thioester bond. The addition and removal of this modification is controlled by both palmitoyl acyl-transferases and thioesterases. Using bioinformatic analysis, we identified 22 DHHC family palmitoyl acyl-transferase homologs in the Drosophila genome. We used in situ hybridization, RT-PCR, and published FlyAtlas microarray data to characterize the expression patterns of all 22 fly homologs. Our results indicate that all are expressed genes, but several, including CG1407, CG4676, CG5620, CG6017/dHIP14, CG6618, CG6627, and CG17257 appear to be enriched in neural tissues suggesting that they are important for neural function. Furthermore, we have found that several may be expressed in a sex-specific manner with adult male-specific expression of CG4483 and CG17195. Using tagged versions of the DHHC genes, we demonstrate that fly DHHC proteins are primarily located in either the Golgi Apparatus or Endoplasmic Reticulum in S2 cells, except for CG1407, which was found on the plasma membrane. We also characterized the subcellular localization and expression of the three known thioesterases: Palmitoyl-protein Thioesterase 1 (Ppt1), Palmitoyl-protein Thioesterase 2 (Ppt2), and Acyl-protein Thioesterase 1 (APT1). Our results indicate that Ppt1 and Ppt2 are the major lysosomal thioesterases while APT1 is the likely cytoplasmic thioesterase. Finally, in vivo rescue experiments show that Ppt2 expression cannot rescue the neural inclusion phenotypes associated with loss of Ppt1, further supporting distinct functions and substrates for these two thioesterases. These results will serve as the basis for a more complete understanding of the protein palmitoylome's normal cellular functions in the fly and will lead to further insights into the molecular etiology of diseases associated with the mis-regulation of palmitoylation. PMID:18719403

Succinyl-CoA:Mesaconate CoA-Transferase and Mesaconyl-CoA Hydratase, Enzymes of the Methylaspartate Cycle in Haloarcula hispanica.

PubMed

Borjian, Farshad; Johnsen, Ulrike; Schönheit, Peter; Berg, Ivan A

2017-01-01

Growth on acetate or other acetyl-CoA-generating substrates as a sole source of carbon requires an anaplerotic pathway for the conversion of acetyl-CoA into cellular building blocks. Haloarchaea (class Halobacteria ) possess two different anaplerotic pathways, the classical glyoxylate cycle and the novel methylaspartate cycle. The methylaspartate cycle was discovered in Haloarcula spp. and operates in ∼40% of sequenced haloarchaea. In this cycle, condensation of one molecule of acetyl-CoA with oxaloacetate gives rise to citrate, which is further converted to 2-oxoglutarate and then to glutamate. The following glutamate rearrangement and deamination lead to mesaconate (methylfumarate) that needs to be activated to mesaconyl-C1-CoA and hydrated to β-methylmalyl-CoA. The cleavage of β-methylmalyl-CoA results in the formation of propionyl-CoA and glyoxylate. The carboxylation of propionyl-CoA and the condensation of glyoxylate with another acetyl-CoA molecule give rise to two C 4 -dicarboxylic acids, thus regenerating the initial acetyl-CoA acceptor and forming malate, its final product. Here we studied two enzymes of the methylaspartate cycle from Haloarcula hispanica , succinyl-CoA:mesaconate CoA-transferase (mesaconate CoA-transferase, Hah_1336) and mesaconyl-CoA hydratase (Hah_1340). Their genes were heterologously expressed in Haloferax volcanii , and the corresponding enzymes were purified and characterized. Mesaconate CoA-transferase was specific for its physiological substrates, mesaconate and succinyl-CoA, and produced only mesaconyl-C1-CoA and no mesaconyl-C4-CoA. Mesaconyl-CoA hydratase had a 3.5-fold bias for the physiological substrate, mesaconyl-C1-CoA, compared to mesaconyl-C4-CoA, and virtually no activity with other tested enoyl-CoA/3-hydroxyacyl-CoA compounds. Our results further prove the functioning of the methylaspartate cycle in haloarchaea and suggest that mesaconate CoA-transferase and mesaconyl-CoA hydratase can be regarded as

The synthesis of ethacrynic acid thiazole derivatives as glutathione S-transferase pi inhibitors.

PubMed

Li, Ting; Liu, Guyue; Li, Hongcai; Yang, Xinmei; Jing, Yongkui; Zhao, Guisen

2012-04-01

Glutathione S-transferase pi (GSTpi) is a phase II enzyme which protects cells from death and detoxifies chemotherapeutic agents in cancer cells. Ethacrynic acid (EA) is a weak GSTpi inhibitor. Structure modifications were done to improve the ability of EA to inhibit GSTpi activity. Eighteen EA thiazole derivatives were designed and synthesized. Compounds 9a, 9b and 9c with a replacement of carboxyl group of EA by a heterocyclic thiazole exhibited improvement over EA to inhibit GSTpi activity. Copyright © 2012 Elsevier Ltd. All rights reserved.

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

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

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

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

Probing the Donor and Acceptor Substrate Specificity of the Gamma-Glutamyl Transpeptidase

DTIC Science & Technology

2012-01-17

glutathione can function as a source of cysteine. Mutant strains of F. tularensis that lack functional GGT have been shown to have impaired intracellular...conservation of structure and function between human and bacterial GGT homologues, significant differences in acceptor substrate and inhibitor preferences are...with the lowest value of MODELER objective function . The three-dimensional (3D) fold of the generated models was verified with PROSA II,40 and

ROLE OF STEROID HORMONES AND DECIDUAL INDUCTION IN THE REGULATION OF ADENOSINE DIPHOSPHORIBOSYL TRANSFERASE ACTIVITY IN RAT ENDOMETRIUM

EPA Science Inventory

To assess the effect of ovarian steroid hormones on enzyme activity, adenosine diphosphoribosyl transferase (ADPRT) was measured in endometrial nuclei isolated on estrus and on d 4 from rats ovariectomized on estrus (d 0) and treated d 0-3 with (a) vehicle, (b) 1 ug estrone/d (E)...

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

EPA Science Inventory

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

Dimethyl adenosine transferase (KsgA) deficiency in Salmonella Enteritidis confers susceptibility to high osmolarity and virulence attenuation in chickens

USDA-ARS?s Scientific Manuscript database

: Dimethyladenosine transferase (KsgA) performs diverse roles in bacteria including ribosomal maturation, DNA mismatch repair, and synthesis of KsgA is responsive to antibiotics and cold temperature. We previously showed that ksgA mutation in Salmonella Enteritidis results in impaired invasiveness i...

Method of incident low-energy gamma-ray direction reconstruction in the GAMMA-400 gamma-ray space telescope

NASA Astrophysics Data System (ADS)

Kheymits, M. D.; Leonov, A. A.; Zverev, V. G.; Galper, A. M.; Arkhangelskaya, I. V.; Arkhangelskiy, A. I.; Suchkov, S. I.; Topchiev, N. P.; Yurkin, Yu T.; Bakaldin, A. V.; Dalkarov, O. D.

2016-02-01

The GAMMA-400 gamma-ray space-based telescope has as its main goals to measure cosmic γ-ray fluxes and the electron-positron cosmic-ray component produced, theoretically, in dark-matter-particles decay or annihilation processes, to search for discrete γ-ray sources and study them in detail, to examine the energy spectra of diffuse γ-rays — both galactic and extragalactic — and to study gamma-ray bursts (GRBs) and γ-rays from the active Sun. Scientific goals of GAMMA-400 telescope require fine angular resolution. The telescope is of a pair-production type. In the converter-tracker, the incident gamma-ray photon converts into electron-positron pair in the tungsten layer and then the tracks are detected by silicon- strip position-sensitive detectors. Multiple scattering processes become a significant obstacle in the incident-gamma direction reconstruction for energies below several gigaelectronvolts. The method of utilising this process to improve the resolution is proposed in the presented work.

[Metabolism of rat liver in the electrostatic field and in the faraday cage before and after hepatectomy (author's transl)].

PubMed

Klingenberg, H G; Möse, J R; Fischer, G; Porta, J; Sadjak, A

1975-10-01

Investigations were performed with the aim of establishing the influence of various environmental conditions (such as steady field conditions, climatized laboratories, Faraday's cage) on a number of enzymic activities in the rat (including glutamic oxaloacetic tic transaminase, glutamic pyruvic transaminase, lactic dehydrogenase, gamma-glutamyl transpeptidase, acid phosphatase), as well as the serum concentrations of triglycerides, the oxygen consumption of hepatic parenchyma cells, and the influence on the incorporation of 3H-thymidine (following partial hepatectomy). In the steady field, the activities of the cytoplasmic enzymes (GOT, GPT, LDH) were higher then under Faraday conditions. The same applies both to the hepatic oxygen consumption and to the neutral fat serum levels. The control values always remained within the range of the results obtained under steady field or Faraday conditions. In the structure-linked enzymes (gamma-glutamyl transpeptidase, acid phosphatase) the results were not uniform. Following partial hepatectomy, and under steady field conditions, the serum triglyceride concentrations showed a less pronounced drop than they did in the controls. Under selected environmental conditions, the results obtained lie within the physiological range. The present findings, therefore, do not permit definite conclusions to be drawn on favourable or unfavourable effects exerted by the different types of electroclimates.

MOF Acetyl Transferase Regulates Transcription and Respiration in Mitochondria.

PubMed

Chatterjee, Aindrila; Seyfferth, Janine; Lucci, Jacopo; Gilsbach, Ralf; Preissl, Sebastian; Böttinger, Lena; Mårtensson, Christoph U; Panhale, Amol; Stehle, Thomas; Kretz, Oliver; Sahyoun, Abdullah H; Avilov, Sergiy; Eimer, Stefan; Hein, Lutz; Pfanner, Nikolaus; Becker, Thomas; Akhtar, Asifa

2016-10-20

A functional crosstalk between epigenetic regulators and metabolic control could provide a mechanism to adapt cellular responses to environmental cues. We report that the well-known nuclear MYST family acetyl transferase MOF and a subset of its non-specific lethal complex partners reside in mitochondria. MOF regulates oxidative phosphorylation by controlling expression of respiratory genes from both nuclear and mtDNA in aerobically respiring cells. MOF binds mtDNA, and this binding is dependent on KANSL3. The mitochondrial pool of MOF, but not a catalytically deficient mutant, rescues respiratory and mtDNA transcriptional defects triggered by the absence of MOF. Mof conditional knockout has catastrophic consequences for tissues with high-energy consumption, triggering hypertrophic cardiomyopathy and cardiac failure in murine hearts; cardiomyocytes show severe mitochondrial degeneration and deregulation of mitochondrial nutrient metabolism and oxidative phosphorylation pathways. Thus, MOF is a dual-transcriptional regulator of nuclear and mitochondrial genomes connecting epigenetics and metabolism. Copyright © 2016 Elsevier Inc. All rights reserved.

Design and Performance of the GAMMA-400 Gamma-Ray Telescope for Dark Matter Searches

NASA Technical Reports Server (NTRS)

Galper, A.M.; Adriani, O.; Aptekar, R. L.; Arkhangelskaja, I. V.; Arkhangelskiy, A.I.; Boezio, M.; Bonvicini, V.; Boyarchuk, K. A.; Fradkin, M. I.; Gusakov, Yu. V.;

Transgenic expression of a maize geranyl geranyl transferase gene sequence in maize callus increases resistance to ear rot pathogens

USDA-ARS?s Scientific Manuscript database

Determining the genes responsible for pest resistance in maize can allow breeders to develop varieties with lower losses and less contamination with undesirable toxins. A gene sequence coding for a geranyl geranyl transferase-like protein located in a fungal ear rot resistance quantitative trait loc...

A Novel Glutamyl (Aspartyl)-Specific Aminopeptidase A from Lactobacillus delbrueckii with Promising Properties for Application.

PubMed

Stressler, Timo; Ewert, Jacob; Merz, Michael; Funk, Joshua; Claaßen, Wolfgang; Lutz-Wahl, Sabine; Schmidt, Herbert; Kuhn, Andreas; Fischer, Lutz

2016-01-01

Lactic acid bacteria (LAB) are auxotrophic for a number of amino acids. Thus, LAB have one of the strongest proteolytic systems to acquit their amino acid requirements. One of the intracellular exopeptidases present in LAB is the glutamyl (aspartyl) specific aminopeptidase (PepA; EC 3.4.11.7). Most of the PepA enzymes characterized yet, belonged to Lactococcus lactis sp., but no PepA from a Lactobacillus sp. has been characterized so far. In this study, we cloned a putative pepA gene from Lb. delbrueckii ssp. lactis DSM 20072 and characterized it after purification. For comparison, we also cloned, purified and characterized PepA from Lc. lactis ssp. lactis DSM 20481. Due to the low homology between both enzymes (30%), differences between the biochemical characteristics were very likely. This was confirmed, for example, by the more acidic optimum pH value of 6.0 for Lb-PepA compared to pH 8.0 for Lc-PepA. In addition, although the optimum temperature is quite similar for both enzymes (Lb-PepA: 60°C; Lc-PepA: 65°C), the temperature stability after three days, 20°C below the optimum temperature, was higher for Lb-PepA (60% residual activity) than for Lc-PepA (2% residual activity). EDTA inhibited both enzymes and the strongest activation was found for CoCl2, indicating that both enzymes are metallopeptidases. In contrast to Lc-PepA, disulfide bond-reducing agents such as dithiothreitol did not inhibit Lb-PepA. Finally, Lb-PepA was not product-inhibited by L-Glu, whereas Lc-PepA showed an inhibition.

A Novel Glutamyl (Aspartyl)-Specific Aminopeptidase A from Lactobacillus delbrueckii with Promising Properties for Application

PubMed Central

Stressler, Timo; Ewert, Jacob; Merz, Michael; Funk, Joshua; Claaßen, Wolfgang; Lutz-Wahl, Sabine; Schmidt, Herbert; Kuhn, Andreas; Fischer, Lutz

2016-01-01

Lactic acid bacteria (LAB) are auxotrophic for a number of amino acids. Thus, LAB have one of the strongest proteolytic systems to acquit their amino acid requirements. One of the intracellular exopeptidases present in LAB is the glutamyl (aspartyl) specific aminopeptidase (PepA; EC 3.4.11.7). Most of the PepA enzymes characterized yet, belonged to Lactococcus lactis sp., but no PepA from a Lactobacillus sp. has been characterized so far. In this study, we cloned a putative pepA gene from Lb. delbrueckii ssp. lactis DSM 20072 and characterized it after purification. For comparison, we also cloned, purified and characterized PepA from Lc. lactis ssp. lactis DSM 20481. Due to the low homology between both enzymes (30%), differences between the biochemical characteristics were very likely. This was confirmed, for example, by the more acidic optimum pH value of 6.0 for Lb-PepA compared to pH 8.0 for Lc-PepA. In addition, although the optimum temperature is quite similar for both enzymes (Lb-PepA: 60°C; Lc-PepA: 65°C), the temperature stability after three days, 20°C below the optimum temperature, was higher for Lb-PepA (60% residual activity) than for Lc-PepA (2% residual activity). EDTA inhibited both enzymes and the strongest activation was found for CoCl2, indicating that both enzymes are metallopeptidases. In contrast to Lc-PepA, disulfide bond-reducing agents such as dithiothreitol did not inhibit Lb-PepA. Finally, Lb-PepA was not product-inhibited by L-Glu, whereas Lc-PepA showed an inhibition. PMID:27003449

Cosmic Gamma-Rays

Science.gov Websites

[Argonne Logo] [DOE Logo] Cosmic Gamma-Rays Home Publications Talks People Students Argonne > ; HEP > Cosmic Gamma-Rays Projects VERITAS Past Projects TrICE What's New CTA Cosmic Gamma-Rays The

Design and Performance of the GAMMA-400 Gamma-Ray Telescope for Dark Matter Searches

NASA Technical Reports Server (NTRS)

Galper, A. M.; Adriani, O.; Aptekar, R. L.; Arkhangelskaja, I. V.; Arkhangelskiy, A. I.; Boezio, M.; Bonvicini, V.; Boyarchuk, K. A.; Fradkin, M. I.; Gusakov, Yu V.;

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

PubMed

Schroer, Kathy T; Gibson, Aaron M; Sivaprasad, Umasundari; Bass, Stacey A; Ericksen, Mark B; Wills-Karp, Marsha; Lecras, Tim; Fitzpatrick, Anne M; Brown, Lou Ann S; Stringer, Keith F; Hershey, Gurjit K Khurana

2011-09-01

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

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

PubMed

Matsumoto, M; Imagawa, M; Aoki, Y

2000-07-01

Using chloramphenicol acetyltransferase assays we showed that epidermal growth factor (EGF), transforming growth factor alpha (TGF alpha), and 3,3',4,4',5-pentachlorobiphenyl (PenCB) induce class Pi glutathione S-transferase (GSTP1) in primary cultured rat liver parenchymal cells. GSTP1 enhancer I (GPEI), which is required for the stimulation of GSTP1 expression by PenCB, also mediates EGF and TGF alpha stimulation of GSTP1 gene expression. However, hepatocyte growth factor and insulin did not stimulate GPEI-mediated gene expression. On the other hand, the antioxidant reagents butylhydroxyanisole and t-butylhydroquinone, stimulated GPEI-mediated gene expression, but the level of GSTP1 mRNA was not elevated. Our observations suggest that EGF and TGF alpha induce GSTP1 by the same signal transduction pathway as PenCB. Since the sequence of GPEI is similar to that of the antioxidant responsive element (ARE), some factors which bind to ARE might play a role in GPEI-mediated gene expression.

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

PubMed Central

Matsumoto, M; Imagawa, M; Aoki, Y

2000-01-01

Using chloramphenicol acetyltransferase assays we showed that epidermal growth factor (EGF), transforming growth factor alpha (TGF alpha), and 3,3',4,4',5-pentachlorobiphenyl (PenCB) induce class Pi glutathione S-transferase (GSTP1) in primary cultured rat liver parenchymal cells. GSTP1 enhancer I (GPEI), which is required for the stimulation of GSTP1 expression by PenCB, also mediates EGF and TGF alpha stimulation of GSTP1 gene expression. However, hepatocyte growth factor and insulin did not stimulate GPEI-mediated gene expression. On the other hand, the antioxidant reagents butylhydroxyanisole and t-butylhydroquinone, stimulated GPEI-mediated gene expression, but the level of GSTP1 mRNA was not elevated. Our observations suggest that EGF and TGF alpha induce GSTP1 by the same signal transduction pathway as PenCB. Since the sequence of GPEI is similar to that of the antioxidant responsive element (ARE), some factors which bind to ARE might play a role in GPEI-mediated gene expression. PMID:10861232

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

PubMed

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

2012-11-16

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

Self-cloning baker's yeasts that accumulate proline enhance freeze tolerance in doughs.

PubMed

Kaino, Tomohiro; Tateiwa, Tetsuya; Mizukami-Murata, Satomi; Shima, Jun; Takagi, Hiroshi

2008-09-01

We constructed self-cloning diploid baker's yeast strains by disrupting PUT1, encoding proline oxidase, and replacing the wild-type PRO1, encoding gamma-glutamyl kinase, with a pro1(D154N) or pro1(I150T) allele. The resultant strains accumulated intracellular proline and retained higher-level fermentation abilities in the frozen doughs than the wild-type strain. These results suggest that proline-accumulating baker's yeast is suitable for frozen-dough baking.

Function and phylogeny of bacterial butyryl-CoA:acetate transferases and their diversity in the proximal colon of swine

USDA-ARS?s Scientific Manuscript database

Studying the host-associated butyrate-producing bacterial community is important because butyrate is essential for colonic homeostasis and gut health. Previous research has identified the butyryl-coA:acetate transferase (2.3.8.3) as a the main gene for butyrate production in intestinal ecosystems; h...

Optical gamma thermometer

DOEpatents

Koster, Glen Peter; Xia, Hua; Lee, Boon Kwee

2013-08-06

An optical gamma thermometer includes a metal mass having a temperature proportional to a gamma flux within a core of a nuclear reactor, and an optical fiber cable for measuring the temperature of the heated metal mass. The temperature of the heated mass may be measured by using one or more fiber grating structures and/or by using scattering techniques, such as Raman, Brillouin, and the like. The optical gamma thermometer may be used in conjunction with a conventional reactor heat balance to calibrate the local power range monitors over their useful in-service life. The optical gamma thermometer occupies much less space within the in-core instrument tube and costs much less than the conventional gamma thermometer.

O-linked-N-acetylglucosamine modification of mammalian Notch receptors by an atypical O-GlcNAc transferase Eogt1

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

Sakaidani, Yuta; Ichiyanagi, Naoki; Saito, Chika

2012-03-02

Highlights: Black-Right-Pointing-Pointer We characterized A130022J15Rik (Eogt1)-a mouse gene homologous to Drosophila Eogt. Black-Right-Pointing-Pointer Eogt1 encodes EGF domain O-GlcNAc transferase. Black-Right-Pointing-Pointer Expression of Eogt1 in Drosophila rescued the cell-adhesion defect in the Eogt mutant. Black-Right-Pointing-Pointer O-GlcNAcylation reaction in the secretory pathway is conserved through evolution. -- Abstract: O-linked-{beta}-N-acetylglucosamine (O-GlcNAc) modification is a unique cytoplasmic and nuclear protein modification that is common in nearly all eukaryotes, including filamentous fungi, plants, and animals. We had recently reported that epidermal growth factor (EGF) repeats of Notch and Dumpy are O-GlcNAcylated by an atypical O-GlcNAc transferase, EOGT, in Drosophila. However, no study has yet shownmore » whether O-GlcNAcylation of extracellular proteins is limited to insects such as Drosophila or whether it occurs in other organisms, including mammals. Here, we report the characterization of A130022J15Rik, a mouse gene homolog of Drosophila Eogt (Eogt 1). Enzymatic analysis revealed that Eogt1 has a substrate specificity similar to that of Drosophila EOGT, wherein the Thr residue located between the fifth and sixth conserved cysteines of the folded EGF-like domains is modified. This observation is supported by the fact that the expression of Eogt1 in Drosophila rescued the cell-adhesion defect caused by Eogt downregulation. In HEK293T cells, Eogt1 expression promoted modification of Notch1 EGF repeats by O-GlcNAc, which was further modified, at least in part, by galactose to generate a novel O-linked-N-acetyllactosamine structure. These results suggest that Eogt1 encodes EGF domain O-GlcNAc transferase and that O-GlcNAcylation reaction in the secretory pathway is a fundamental biochemical process conserved through evolution.« less

An inflammation-based prognostic score (mGPS) predicts cancer survival independent of tumour site: a Glasgow Inflammation Outcome Study.

PubMed

Proctor, M J; Morrison, D S; Talwar, D; Balmer, S M; O'Reilly, D S J; Foulis, A K; Horgan, P G; McMillan, D C

2011-02-15

A selective combination of C-reactive protein and albumin (termed the modified Glasgow Prognostic Score, mGPS) has been shown to have prognostic value, independent of tumour stage, in lung, gastrointestinal and renal cancers. It is also of interest that liver function tests such as bilirubin, alkaline phosphatase and γ-glutamyl transferase, as well as serum calcium, have also been reported to predict cancer survival. The aim of the present study was to examine the relationship between an inflammation-based prognostic score (mGPS), biochemical parameters, tumour site and survival in a large cohort of patients with cancer. Patients (n=21,669) who had an incidental blood sample taken between 2000 and 2006 for C-reactive protein, albumin and calcium (and liver function tests where available) and a diagnosis of cancer were identified. Of this group 9608 patients who had an ongoing malignant process were studied (sampled within 2 years before diagnosis). Also a subgroup of 5397 sampled at the time of diagnosis (sampled within 2 months prior to diagnosis) were examined. Cancers were grouped by tumour site in accordance with International Classification of Diseases 10 (ICD 10). On follow up, there were 6005 (63%) deaths of which 5122 (53%) were cancer deaths. The median time from blood sampling to diagnosis was 1.4 months. Increasing age, male gender and increasing deprivation was associated with a reduced 5-year overall and cancer-specific survival (all P<0.001). An elevated mGPS, adjusted calcium, bilirubin, alkaline phosphatase, aspartate transaminase, alanine transaminase and γ-glutamyl transferase were associated with a reduced 5-year overall and cancer-specific survival (independent of age, sex and deprivation in all patients sampled), as well as within the time of diagnosis subgroup (all P<0.001). An increasing mGPS was predictive of a reduced cancer-specific survival in all cancers (all P<0.001). The results of the present study indicate that the mGPS is a

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

PubMed Central

Ralat, Luis A.; Colman, Roberta F.

2003-01-01

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

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

PubMed

Ralat, Luis A; Colman, Roberta F

2003-11-01

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

Implications of Gamma-Ray Transparency Constraints in Blazars: Minimum Distances and Gamma-Ray Collimation

NASA Technical Reports Server (NTRS)

Becker, Peter A.; Kafatos, Menas

1995-01-01

We develop a general expression for the gamma - gamma absorption coefficient, alpha(sub gamma(gamma)) for gamma-rays propagating in an arbitrary direction at an arbitrary point in space above an X-ray-emitting accretion disk. The X-ray intensity is assumed to vary as a power law in energy and radius between the outer disk radius, R(sub 0), and the inner radius, R(sub ms) which is the radius of marginal stability for a Schwarzschild black hole. We use our result for alpha(sub gamma(gamma)) to calculate the gamma - gamma optical depth, tau(sub gamma(gamma)) for gamma - rays created at height z and propagating at angle Phi relative to the disk axis, and we show that for Phi = 0 and z greater than or approx equal to R(sub 0), tau(sub gamma(gamma)) proportional to Epsilon(sup alpha)z(sup -2(alpha) - 3), where alpha is the X-ray spectral index and Epsilon is the gamma - ray energy. As an application, we use our formalism to compute the minimum distance between the central black hole and the site of production of the gamma-rays detected by EGRET during the 1991 June flare of 3C 279. In order to obtain an upper limit, we assume that all of the X-rays observed contemporaneously by Ginga were emitted by the disk. Our results suggest that the observed gamma - rays may have originated within less than or approx equal to 45 GM/sq c from a black hole of mass greater than or approx equal to 10(exp 9) solar mass, perhaps in active plasma located above the central funnel of the accretion disk. This raises the possibility of establishing a direct connection between the production of the observed gamma - rays and the accretion of material onto the black hole. We also consider the variation of the optical depth as a function of the angle of propagation Phi. Our results indicate that the "focusing" of the gamma - rays along the disk axis due to pair production is strong enough to explain the observed degree of alignment in blazar sources. If the gamma - rays are produced isotropically

Design and performance of the GAMMA-400 gamma-ray telescope for dark matter searches

NASA Astrophysics Data System (ADS)

Galper, A. M.; Adriani, O.; Aptekar, R. L.; Arkhangelskaja, I. V.; Arkhangelskiy, A. I.; Boezio, M.; Bonvicini, V.; Boyarchuk, K. A.; Fradkin, M. I.; Gusakov, Yu. V.; Kaplin, V. A.; Kachanov, V. A.; Kheymits, M. D.; Leonov, A. A.; Longo, F.; Mazets, E. P.; Maestro, P.; Marrocchesi, P.; Mereminskiy, I. A.; Mikhailov, V. V.; Moiseev, A. A.; Mocchiutti, E.; Mori, N.; Moskalenko, I. V.; Naumov, P. Yu.; Papini, P.; Picozza, P.; Rodin, V. G.; Runtso, M. F.; Sparvoli, R.; Spillantini, P.; Suchkov, S. I.; Tavani, M.; Topchiev, N. P.; Vacchi, A.; Vannuccini, E.; Yurkin, Yu. T.; Zampa, N.; Zverev, V. G.; Zirakashvili, V. N.

2013-02-01

The GAMMA-400 gamma-ray telescope is designed to measure the fluxes of gamma-rays and cosmic-ray electrons + positrons, which can be produced by annihilation or decay of the dark matter particles, as well as to survey the celestial sphere in order to study point and extended sources of gamma-rays, measure energy spectra of Galactic and extragalactic diffuse gamma-ray emission, gamma-ray bursts, and gamma-ray emission from the Sun. GAMMA-400 covers the energy range from 100 MeV to 3000 GeV. Its angular resolution is ~0.01° (Eγ > 100 GeV), the energy resolution ~1% (Eγ > 10 GeV), and the proton rejection factor ~106. GAMMA-400 will be installed on the Russian space platform Navigator. The beginning of observations is planned for 2018.

Discovery of the ammonium substrate site on glutamine synthetase, a third cation binding site.

PubMed Central

Liaw, S. H.; Kuo, I.; Eisenberg, D.

1995-01-01

Glutamine synthetase (GS) catalyzes the ATP-dependent condensation of ammonia and glutamate to yield glutamine, ADP, and inorganic phosphate in the presence of divalent cations. Bacterial GS is an enzyme of 12 identical subunits, arranged in two rings of 6, with the active site between each pair of subunits in a ring. In earlier work, we have reported the locations within the funnel-shaped active site of the substrates glutamate and ATP and of the two divalent cations, but the site for ammonia (or ammonium) has remained elusive. Here we report the discovery by X-ray crystallography of a binding site on GS for monovalent cations, Tl+ and Cs+, which is probably the binding site for the substrate ammonium ion. Fourier difference maps show the following. (1) Tl+ and Cs+ bind at essentially the same site, with ligands being Glu 212, Tyr 179, Asp 50', Ser 53' of the adjacent subunit, and the substrate glutamate. From its position adjacent to the substrate glutamate and the cofactor ADP, we propose that this monovalent cation site is the substrate ammonium ion binding site. This proposal is supported by enzyme kinetics. Our kinetic measurements show that Tl+, Cs+, and NH4+ are competitive inhibitors to NH2OH in the gamma-glutamyl transfer reaction. (2) GS is a trimetallic enzyme containing two divalent cation sites (n1, n2) and one monovalent cation site per subunit. These three closely spaced ions are all at the active site: the distance between n1 and n2 is 6 A, between n1 and Tl+ is 4 A, and between n2 and Tl+ is 7 A. Glu 212 and the substrate glutamate are bridging ligands for the n1 ion and Tl+. (3) The presence of a monovalent cation in this site may enhance the structural stability of GS, because of its effect of balancing the negative charges of the substrate glutamate and its ligands and because of strengthening the "side-to-side" intersubunit interaction through the cation-protein bonding. (4) The presence of the cofactor ADP increases the Tl+ binding to GS

S-Nitrosation destabilizes glutathione transferase P1-1.

PubMed

Balchin, David; Stoychev, Stoyan H; Dirr, Heini W

2013-12-23

Protein S-nitrosation is a post-translational modification that regulates the function of more than 500 human proteins. Despite its apparent physiological significance, S-nitrosation is poorly understood at a molecular level. Here, we investigated the effect of S-nitrosation on the activity, structure, stability, and dynamics of human glutathione transferase P1-1 (GSTP1-1), an important detoxification enzyme ubiquitous in aerobes. S-Nitrosation at Cys47 and Cys101 reduces the activity of the enzyme by 94%. Circular dichroism spectroscopy, acrylamide quenching, and amide hydrogen-deuterium exchange mass spectrometry experiments indicate that the loss of activity is caused by the introduction of local disorder at the active site of GSTP1-1. Furthermore, the modification destabilizes domain 1 of GSTP1-1 against denaturation, smoothing the unfolding energy landscape of the protein and introducing a refolding defect. In contrast, S-nitrosation at Cys101 alone introduces a refolding defect in domain 1 but compensates by stabilizing the domain kinetically. These data elucidate the physical basis for the regulation of GSTP1-1 by S-nitrosation and provide general insight into the consequences of S-nitrosation on protein stability and dynamics.

Madumycin II inhibits peptide bond formation by forcing the peptidyl transferase center into an inactive state

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

Osterman, Ilya A.; Khabibullina, Nelli F.; Komarova, Ekaterina S.

The emergence of multi-drug resistant bacteria is limiting the effectiveness of commonly used antibiotics, which spurs a renewed interest in revisiting older and poorly studied drugs. Streptogramins A is a class of protein synthesis inhibitors that target the peptidyl transferase center (PTC) on the large subunit of the ribosome. In this work, we have revealed the mode of action of the PTC inhibitor madumycin II, an alanine-containing streptogramin A antibiotic, in the context of a functional 70S ribosome containing tRNA substrates. Madumycin II inhibits the ribosome prior to the first cycle of peptide bond formation. It allows binding of themore » tRNAs to the ribosomal A and P sites, but prevents correct positioning of their CCA-ends into the PTC thus making peptide bond formation impossible. We also revealed a previously unseen drug-induced rearrangement of nucleotides U2506 and U2585 of the 23S rRNA resulting in the formation of the U2506•G2583 wobble pair that was attributed to a catalytically inactive state of the PTC. The structural and biochemical data reported here expand our knowledge on the fundamental mechanisms by which peptidyl transferase inhibitors modulate the catalytic activity of the ribosome.« less

Increase in neutrophil Fc gamma receptor I expression following interferon gamma treatment in rheumatoid arthritis.

PubMed Central

Goulding, N J; Knight, S M; Godolphin, J L; Guyre, P M

1992-01-01

The therapeutic potential of interferon gamma (IFN gamma) in a number of disease states is still being explored, but progress is hampered by the lack of a suitable measure of in vivo biological activity. To assess the in vivo biological effects of recombinant human IFN gamma (rhIFN gamma), 14 patients were studied in a randomised, prospective, double blind, placebo controlled trial of this cytokine for the treatment of rheumatoid arthritis. The levels of Fc gamma receptors on peripheral blood neutrophils were measured at baseline and after 21 days of once daily, subcutaneous injections of rhIFN gamma or placebo. An induction of neutrophil Fc gamma receptor type I (Fc gamma RI) was seen in the group of patients receiving recombinant human rhIFN gamma but not in those receiving placebo. No change in the expression of Fc gamma RII or Fc gamma RIII was detected. The amount of induction of Fc gamma RI detected on the neutrophils of patients receiving rhIFN gamma did not correlate with clinical measures of response at either 21 days or at the end of the study (24 weeks). No significant clinical responses were observed in the rhIFN gamma group at these times. These data confirm that the reported in vitro effect of IFN gamma on human neutrophil Fc receptor expression can be reproduced in vivo. PMID:1534001

Increase in neutrophil Fc gamma receptor I expression following interferon gamma treatment in rheumatoid arthritis.

PubMed

Goulding, N J; Knight, S M; Godolphin, J L; Guyre, P M

1992-04-01

The therapeutic potential of interferon gamma (IFN gamma) in a number of disease states is still being explored, but progress is hampered by the lack of a suitable measure of in vivo biological activity. To assess the in vivo biological effects of recombinant human IFN gamma (rhIFN gamma), 14 patients were studied in a randomised, prospective, double blind, placebo controlled trial of this cytokine for the treatment of rheumatoid arthritis. The levels of Fc gamma receptors on peripheral blood neutrophils were measured at baseline and after 21 days of once daily, subcutaneous injections of rhIFN gamma or placebo. An induction of neutrophil Fc gamma receptor type I (Fc gamma RI) was seen in the group of patients receiving recombinant human rhIFN gamma but not in those receiving placebo. No change in the expression of Fc gamma RII or Fc gamma RIII was detected. The amount of induction of Fc gamma RI detected on the neutrophils of patients receiving rhIFN gamma did not correlate with clinical measures of response at either 21 days or at the end of the study (24 weeks). No significant clinical responses were observed in the rhIFN gamma group at these times. These data confirm that the reported in vitro effect of IFN gamma on human neutrophil Fc receptor expression can be reproduced in vivo.

Gamma Knife

MedlinePlus

... equipment? How is safety ensured? What is this equipment used for? The Gamma Knife® and its associated ... in size. top of page How does the equipment work? The Gamma Knife® utilizes a technique called ...

Gamma-400 Science Objectives Built on the Current HE Gamma-Ray and CR Results

NASA Technical Reports Server (NTRS)

Moiseev, Alexander; Mitchell, John; Thompson, David

2012-01-01

The main scientific interest of the Russian Gamma-400 team: Observe gamma-rays above approximately 50 GeV with excellent energy and angular resolution with the goals of: (1) Studying the fine spectral structure of the isotropic high-energy gamma-radiation, (2) Attempting to identify the many still-unidentified Fermi-LAT gamma-ray sources. Gamma-400 will likely be the only space-based gamma-ray observatory operating at the end of the decade. In our proposed Gamma-400-LE version, it will substantially improve upon the capabilities of Fermi LAT and AGILE in both LE and HE energy range. Measuring gamma-rays from approx 20 MeV to approx 1 TeV for at least 7 years, Gamma-400-LE will address the topics of dark matter, cosmic ray origin and propagation, neutron stars, flaring pulsars, black holes, AGNs, GRBs, and actively participate in multiwavelength campaigns.

Genomic sequences of murine gamma B- and gamma C-crystallin-encoding genes: promoter analysis and complete evolutionary pattern of mouse, rat and human gamma-crystallins.

PubMed

Graw, J; Liebstein, A; Pietrowski, D; Schmitt-John, T; Werner, T

1993-12-22

The murine genes, gamma B-cry and gamma C-cry, encoding the gamma B- and gamma C-crystallins, were isolated from a genomic DNA library. The complete nucleotide (nt) sequences of both genes were determined from 661 and 711 bp, respectively, upstream from the first exon to the corresponding polyadenylation sites, comprising more than 2650 and 2890 bp, respectively. The new sequences were compared to the partial cDNA sequences available for the murine gamma B-cry and gamma C-cry, as well as to the corresponding genomic sequences from rat and man, at both the nt and predicted amino acid (aa) sequence levels. In the gamma B-cry promoter region, a canonical CCAAT-box, a TATA-box, putative NF-I and C/EBP sites were detected. An R-repeat is inserted 366 bp upstream from the transcription start point. In contrast, the gamma C-cry promoter does not contain a CCAAT-box, but some other putative binding sites for transcription factors (AP-2, UBP-1, LBP-1) were located by computer analysis. The promoter regions of all six gamma-cry from mouse, rat and human, except human psi gamma F-cry, were analyzed for common sequence elements. A complex sequence element of about 70-80 bp was found in the proximal promoter, which contains a gamma-cry-specific and almost invariant sequence (crygpel) of 14 nt, and ends with the also invariant TATA-box. Within the complex sequence element, a minimum of three further features specific for the gamma A-, gamma B- and gamma D/E/F-cry genes can be defined, at least two of which were recently shown to be functional. In addition to these four sequence elements, a subtype-specific structure of inverted repeats with different-sized spacers can be deduced from the multiple sequence alignment. A phylogenetic analysis based on the promoter region, as well as the complete exon 3 of all gamma-cry from mouse, rat and man, suggests separation of only five gamma-cry subtypes (gamma A-, gamma B-, gamma C-, gamma D- and gamma E/F-cry) prior to species separation.

Predicting diffusion paths and interface motion in gamma/gamma + beta, Ni-Cr-Al diffusion couples

NASA Technical Reports Server (NTRS)

Nesbitt, J. A.; Heckel, R. W.

1987-01-01

A simplified model has been developed to predict Beta recession and diffusion paths in ternary gamma/gamma + beta diffusion couples (gamma:fcc, beta: NiAl structure). The model was tested by predicting beta recession and diffusion paths for four gamma/gamma + beta, Ni-Cr-Al couples annealed for 100 hours at 1200 C. The model predicted beta recession within 20 percent of that measured for each of the couples. The model also predicted shifts in the concentration of the gamma phase at the gamma/gamma + beta interface within 2 at. pct Al and 6 at. pct Cr of that measured in each of the couples. A qualitative explanation based on simple kinetic and mass balance arguments has been given which demonstrates the necessity for diffusion in the two-phase region of certain gamma/gamma + beta, Ni-Cr-Al couples.

Comparison of gamma-gamma Phase Coarsening Responses of Three Powder Metal Disk Superalloys

NASA Technical Reports Server (NTRS)

Gabb, T. P.; Gayda, J.; Johnson, D. F.; MacKay, R. A.; Rogers, R. B.; Sudbrack, C. K.; Garg, A.; Locci, I. E.; Semiatin, S. L.; Kang, E.

2016-01-01

The phase microstructures of several powder metal (PM) disk superalloys were quantitatively evaluated. Contents, chemistries, and lattice parameters of gamma and gamma strengthening phase were determined for conventionally heat treated Alloy 10, LSHR, and ME3 superalloys, after electrolytic phase extractions. Several of long term heat treatments were then performed, to allow quantification of the precipitation, content, and size distribution of gamma at a long time interval to approximate equilibrium conditions. Additional coarsening heat treatments were performed at multiple temperatures and shorter time intervals, to allow quantification of the precipitation, contents and size distributions of gamma at conditions diverging from equilibrium. Modest differences in gamma and gamma lattice parameters and their mismatch were observed among the alloys, which varied with heat treatment. Yet, gamma coarsening rates were very similar for all three alloys in the heat treatment conditions examined. Alloy 10 had higher gamma dissolution and formation temperatures than LSHR and ME3, but a lower lattice mismatch, which was slightly positive for all three alloys at room temperature. The gamma precipitates of Alloy 10 appeared to remain coherent at higher temperatures than for LSHR and ME3. Higher coarsening rates were observed for gamma precipitates residing along grain boundaries than for those within grains in all three alloys, during slow-moderate quenching from supersolvus solution heat treatments, and during aging at temperatures of 843 C and higher.

The N-methyl-D-aspartate receptor subunits NR2A and NR2B bind to the SH2 domains of phospholipase C-gamma.

PubMed

Gurd, J W; Bissoon, N

1997-08-01

The NMDA receptor has recently been found to be phosphorylated on tyrosine. To assess the possible connection between tyrosine phosphorylation of the NMDA receptor and signaling pathways in the postsynaptic cell, we have investigated the relationship between tyrosine phosphorylation and the binding of NMDA receptor subunits to the SH2 domains of phospholipase C-gamma (PLC-gamma). A glutathione S-transferase (GST) fusion protein containing both the N- and the C-proximal SH2 domains of PLC-gamma was bound to glutathione-agarose and reacted with synaptic junctional proteins and glycoproteins. Tyrosine-phosphorylated PSD-GP180, which has been identified as the NR2B subunit of the NMDA receptor, bound to the SH2-agarose beads in a phosphorylation-dependent fashion. Immunoblot analysis with antibodies specific for individual NMDA receptor subunits showed that both NR2A and NR2B subunits bound to the SH2-agarose. No binding occurred to GST-agarose lacking an associated SH2 domain, indicating that binding was specific for the SH2 domains. The binding of receptor subunits increased after the incubation of synaptic junctions with ATP and decreased after treatment of synaptic junctions with exogenous protein tyrosine phosphatase. Immunoprecipitation experiments confirmed that NR2A and NR2B were phosphorylated on tyrosine and further that tyrosine phosphorylation of each of the subunits was increased after incubation with ATP. The results demonstrate that NMDA receptor subunits NR2A and NR2B will bind to the SH2 domains of PLC-gamma and that isolated synaptic junctions contain endogenous protein tyrosine kinase(s) that can phosphorylate both NR2A and NR2B receptor subunits, and suggest that interaction of the tyrosine-phosphorylated NMDA receptor with proteins that contain SH2 domains may serve to link it to signaling pathways in the postsynaptic cell.

Testing the Effects of SIAH Ubiquitin E3 Ligases on Lysine Acetyl Transferases.

PubMed

Hagenbucher, Jan; Stekman, Hilda; Rodriguez-Gil, Alfonso; Kracht, Michael; Schmitz, M Lienhard

2017-01-01

The family of seven-in-absentia (SIAH) ubiquitin E3 ligases functions in the control of numerous key signaling pathways. These enzymes belong to the RING (really interesting new gene) group of E3 ligases and mediate the attachment of ubiquitin chains to substrates, which then leads to their proteasomal degradation. Here, we describe a protocol that allows measuring SIAH-mediated ubiquitination and degradation of its client proteins as exemplified by acetyl transferases using simple overexpression experiments. The impact of SIAH expression on the relative amounts of target proteins and their mRNAs can be quantified by Western blotting and quantitative PCR (qPCR) as described here.

Golgi targeting of human guanylate-binding protein-1 requires nucleotide binding, isoprenylation, and an IFN-gamma-inducible cofactor.

PubMed

Modiano, Nir; Lu, Yanping E; Cresswell, Peter

2005-06-14

Human guanylate-binding protein-1 (hGBP-1) is a large GTPase, similar in structure to the dynamins. Like many smaller GTPases of the Ras/Rab family, it is farnesylated, suggesting it may dock into membranes and perhaps play a role in intracellular trafficking. To date, however, hGBP-1 has never been associated with a specific intracellular compartment. Here we present evidence that hGBP-1 can associate with the Golgi apparatus. Redistribution from the cytosol to the Golgi was observed by immunofluorescence and subcellular fractionation after aluminum fluoride treatment, suggesting that it occurs when hGBP-1 is in its GTP-bound state. Relocalization was blocked by a farnesyl transferase inhibitor. The C589S mutant of hGBP-1, which cannot be farnesylated, and the previously uncharacterized R48P mutant, which cannot bind GTP, both failed to localize to the Golgi. These two mutants had a dominant-negative effect, preventing endogenous wild-type hGBP-1 from efficiently redistributing after aluminum fluoride treatment. Furthermore, hGBP-1 requires another IFN-gamma-induced factor to be targeted to the Golgi, because constitutively expressed hGBP-1 remained cytosolic in cells treated with aluminum fluoride unless the cells were preincubated with IFN-gamma. Finally, two nonhydrolyzing mutants of hGBP-1, corresponding to active mutants of Ras family proteins, failed to constitutively associate with the Golgi; we propose three possible explanations for this surprising result.

The gamma-ray observatory

NASA Technical Reports Server (NTRS)

1991-01-01

An overview is given of the Gamma Ray Observatory (GRO) mission. Detection of gamma rays and gamma ray sources, operations using the Space Shuttle, and instruments aboard the GRO, including the Burst and Transient Source Experiment (BATSE), the Oriented Scintillation Spectrometer Experiment (OSSE), the Imaging Compton Telescope (COMPTEL), and the Energetic Gamma Ray Experiment Telescope (EGRET) are among the topics surveyed.

High-frequency gamma oscillations coexist with low-frequency gamma oscillations in the rat visual cortex in vitro.

PubMed

Oke, Olaleke O; Magony, Andor; Anver, Himashi; Ward, Peter D; Jiruska, Premysl; Jefferys, John G R; Vreugdenhil, Martin

2010-04-01

Synchronization of neuronal activity in the visual cortex at low (30-70 Hz) and high gamma band frequencies (> 70 Hz) has been associated with distinct visual processes, but mechanisms underlying high-frequency gamma oscillations remain unknown. In rat visual cortex slices, kainate and carbachol induce high-frequency gamma oscillations (fast-gamma; peak frequency approximately 80 Hz at 37 degrees C) that can coexist with low-frequency gamma oscillations (slow-gamma; peak frequency approximately 50 Hz at 37 degrees C) in the same column. Current-source density analysis showed that fast-gamma was associated with rhythmic current sink-source sequences in layer III and slow-gamma with rhythmic current sink-source sequences in layer V. Fast-gamma and slow-gamma were not phase-locked. Slow-gamma power fluctuations were unrelated to fast-gamma power fluctuations, but were modulated by the phase of theta (3-8 Hz) oscillations generated in the deep layers. Fast-gamma was spatially less coherent than slow-gamma. Fast-gamma and slow-gamma were dependent on gamma-aminobutyric acid (GABA)(A) receptors, alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors and gap-junctions, their frequencies were reduced by thiopental and were weakly dependent on cycle amplitude. Fast-gamma and slow-gamma power were differentially modulated by thiopental and adenosine A(1) receptor blockade, and their frequencies were differentially modulated by N-methyl-D-aspartate (NMDA) receptors, GluK1 subunit-containing receptors and persistent sodium currents. Our data indicate that fast-gamma and slow-gamma both depend on and are paced by recurrent inhibition, but have distinct pharmacological modulation profiles. The independent co-existence of fast-gamma and slow-gamma allows parallel processing of distinct aspects of vision and visual perception. The visual cortex slice provides a novel in vitro model to study cortical high-frequency gamma oscillations.

Chronic Intermittent Hypoxia and Acetaminophen Induce Synergistic Liver Injury

PubMed Central

Savransky, Vladimir; Reinke, Christian; Jun, Jonathan; Bevans-Fonti, Shannon; Nanayakkara, Ashika; Li, Jianguo; Myers, Allen C.; Torbenson, Michael S.; Polotsky, Vsevolod Y.

2010-01-01

Obstructive sleep apnea (OSA) leads to chronic intermittent hypoxia (CIH) during sleep. OSA has been associated with liver injury. Acetaminophen (APAP) is one of the most commonly used drugs, which has known hepatotoxicity. The goal of the present study was to examine whether CIH increases liver injury, hepatic oxidative stress and inflammation induced by chronic APAP treatment. C57BL/6J mice were exposed to CIH or intermittent air (IA) for 4 weeks. Mice in both groups were treated with intraperitoneal injections of either APAP (200 mg/kg) or normal saline daily. A combination of CIH and APAP caused liver injury with marked increases in serum alanine aminotransferase, aspartate aminotransferase (AST), gamma glutamyl transferase and total bilirubin levels, whereas CIH alone induced only elevation in serum AST levels. APAP alone did not affect serum levels of liver enzymes. Histopathology revealed hepatic necrosis and increased apoptosis in mice exposed to CIH and APAP, whereas the liver remained intact in all other groups. Mice exposed to CIH and APAP exhibited decreased hepatic glutathione in conjunction with a five-fold increase in nitrotyrosine levels, suggesting formation of toxic peroxynitrite in hepatocytes. APAP or CIH alone had no effect on either glutathione or nitrotyrosine. A combination of CIH and APAP caused marked increases in pro-inflammatory chemokines, monocyte chemoattractant protein-1 and macrophage inflammatory protein-2, which were not observed in mice exposed to CIH or APAP alone. We conclude that CIH and chronic APAP treatment lead to synergistic liver injury, which may have clinical implications for patients with OSA. PMID:19028810

Association between Healthy Eating Index-2010 and Fetuin-A Levels in Patients with Type 2 Diabetes: a Case-Control Study.

PubMed

Roshanzamir, Farzad; Miraghajani, Maryam; Mansourian, Marjan; Ghiasvand, Reza; Safavi, Seyyed Morteza

2017-10-01

The Healthy Eating Index-2010 (HEI-2010) assesses compliance with the 2010 Dietary Guidelines for Americans. Studies suggest that adherence to the HEI-2010 is related to lower the risk of type 2 diabetes (T2D). Fetuin-A, a novel biomarker for T2D, may play a linking role in the inverse association between HEI-2010 and T2D. Thus, a case-control analysis involving 107 patients with T2D and107 healthy subjects was conducted to determine the association between HEI-2010 and serum fetuin-A levels. The results of simple regression analysis showed that fetuin-A levels were positively associated with full name of body mass index (BMI) (p < 0.001), waist circumference (WC) (p < 0.001), fasting blood glucose (FBG) (p < 0.001), triglycerides (TG) (p = 0.003), gamma-glutamyl transferase (GGT) (p < 0.001), and homeostasis model assessment of insulin resistance (HOMA-IR) (p =0.001) and negatively associated with physical activity (PA) (p < 0.001), high-density lipoprotein (HDL) (p = 0.022), and HEI-2010 (p < 0.001) in all subjects. After controlling for confounders, the inverse association between fetuin-A and HEI-2010 remained significant in the subjects with T2D (β = -0.386; p < 0.001), 107 healthy controls (β = -0.237; p = 0.028), and all subjects (β = -0.298; p < 0.001). In conclusion, the present results suggested that higher quality diet assessed by HEI-2010 associates with lower serum fetuin-A levels in people with and without T2D. More studies are needed to confirm these findings.

Hepatic Lipodystrophy in Galloway Calves.

PubMed

Wieland, M; Mann, S; Hafner-Marx, A; Ignatius, A; Metzner, M

2017-05-01

Hepatic lipodystrophy in Galloway calves is a fatal liver disease affecting a small proportion of the Galloway breed described in different parts of Europe and North America during the past decades. The clinical findings include a diversity of neurological signs. Clinical pathology findings frequently indicate hepatobiliary disease. Postmortem examination reveals an enlarged, pale yellow, and firm liver. Histologic lesions include hepatic fibrosis, hepatic lipidosis, and bile duct hyperplasia. To date, the etiopathogenesis remains obscure. Infectious causes, intoxications, and a hereditary origin have been considered. We describe hepatic lipodystrophy in Galloway calves from an extensively farmed cow-calf operation in southern Germany. Main clinical findings in 6 calves were consistent with hepatic encephalopathy. Clinical pathology findings in 5 of 6 tested animals revealed increased concentration of total bilirubin (maximum value [MV], 54 μmol/l; reference range [RR], <8.5 μmol/l), direct bilirubin (MV, 20 μmol/l; RR, <3.4 μmol/l), increased activity of gamma glutamyl transferase (MV, 162 U/l; RR, <36 U/l) and glutamate dehydrogenase (MV, 420 U/l; RR, <16 U/l). In addition, activity of glutathione peroxidase was decreased in all tested ( n = 5) animals (MV, 61 U/g hemoglobin [Hb]; RR, >250 U/g Hb). Postmortem examination in 6 calves revealed a firm, diffusely enlarged yellow liver with a finely nodular surface. Histologic lesions included hepatic fibrosis, hepatic lipidosis, and bile duct hyperplasia. Our findings add to the existing data on hepatic lipodystrophy in the Galloway breed and outline a protocol to aid in the diagnosis of this disorder.

Hepatic lipidosis in anorectic, lactating holstein cattle: a retrospective study of serum biochemical abnormalities.

PubMed

Cebra, C K; Garry, F B; Getzy, D M; Fettman, M J

1997-01-01

The association between hepatic lipidosis (HL) and disease in 59 anorectic, ketotic, lactating Holstein heifers and cows was investigated. Severe HL, as determined by histologic evaluation of liver tissue, was present in 46 animals; only half of these animals required intensive treatment for ketosis, and only half had serum biochemical evidence of liver disease, as determined by the presence of a last value of 2-fold or greater than the upper limit of the reference ranges for at least 2 of the 4 serum tests: gamma-glutamyl transferase, aspartate aminotransferase, and sorbitol dehydrogenase activities and bile acid concentrations. Most cattle with biochemical evidence of liver disease and severe HL had been lactating for 14 or more days. Cows that required intensive treatment inconsistently had serum biochemical evidence of liver disease. Although cattle with severe HL had significantly higher serum bilirubin concentrations and aspartate aminotransferase and sorbitol dehydrogenase activities than cattle with less severe lipidosis, the specificity of abnormally high serum sorbitol dehydrogenase activity or bilirubin concentration for severe lipidosis was only 8%. Abnormally high serum aspartate aminotransferase activity was 83% sensitive and 62% specific for severe lipidosis. Serum glucose and total carbon dioxide concentrations were significantly lower in cattle with severe lipidosis than in those with mild or moderate lipidosis, and low serum glucose or total carbon dioxide concentrations were rare in cattle without severe lipidosis. From these data, we conclude that the use of a single biochemical or histopathologic criterion to define severity of disease or degree of liver compromise in anorectic, ketotic cows results in the misidentification of many animals.

Liraglutide attenuates partial warm ischemia-reperfusion injury in rat livers.

PubMed

Abdelsameea, Ahmed A; Abbas, Noha A T; Abdel Raouf, Samar M

2017-03-01

Ischemia-reperfusion (IR) injury constitutes the most important cause of primary dysfunction of liver grafts. In this study, we have addressed the possible hepatoprotective action of liraglutide against partial warm hepatic IR injury in male rats. Rats were randomly assigned into: sham, IR, and liraglutide-pretreated IR groups. Liraglutide was administered 50 μg/kg s.c. twice daily for 14 days, and then, hepatic IR was induced by clamping portal vein and hepatic artery to left and median lobes for 30 min followed by reperfusion for 24 h. Serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), and gamma glutamyl transferase (GGT) activities were determined. Malondialdehyde (MDA) level, reduced glutathione (GSH) content, tumor necrosis factor-α (TNF-α), phosphoralated Akt (p-Akt), and caspase-3 levels of the liver were determined. Hematoxylin and eosin (H&E) stained sections from liver were examined as well as immunohistochemical sections for detection of Bcl-2 expression. IR injury increased ALT, AST, and GGT while decreased GSH and p-Akt with increase in MDA, TNF-α, and caspase-3 levels in the liver with necrosis and inflammatory cellular infiltration with decreased Bcl-2 expression. Pretreatment with liraglutide decreased ALT, AST, and GGT activities while increased glutathione content and Akt activation with decrements in MDA, TNF-α, and caspase-3 levels with attenuation of necrosis and inflammation while enhanced Bcl-2 expression in the liver. Liraglutide protects against IR injury of the liver through antiinflammatory and antioxidant actions as well as inhibition of apoptosis.

Caffeic acid phenethyl ester preferentially sensitizes CT26 colorectal adenocarcinoma to ionizing radiation without affecting bone marrow radioresponse

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

Chen, Y.-J.; Institute of Traditional Medicine, National Yang-Ming University, Taipei, Taiwan; Graduate Institute of Sport Coaching Science, Chinese Culture University, Taipei, Taiwan

2005-11-15

Purpose: Caffeic acid phenethyl ester (CAPE), a component of propolis, was reported capable of depleting glutathione (GSH). We subsequently examined the radiosensitizing effect of CAPE and its toxicity. Methods and Materials: The effects of CAPE on GSH level, GSH metabolism enzyme activities, NF-{kappa}B activity, and radiosensitivity in mouse CT26 colorectal adenocarcinoma cells were determined. BALB/c mouse with CT26 cells implantation was used as a syngeneic in vivo model for evaluation of treatment and toxicity end points. Results: CAPE entered CT26 cells rapidly and depleted intracellular GSH in CT26 cells, but not in bone marrow cells. Pretreatment with nontoxic doses ofmore » CAPE significantly enhanced cell killing by ionizing radiation (IR) with sensitizer enhancement ratios up to 2.2. Pretreatment of CT26 cells with N-acetyl-L-cysteine reversed the GSH depletion activity and partially blocked the radiosensitizing effect of CAPE. CAPE treatment in CT26 cells increased glutathione peroxidase, decreased glutathione reductase, and did not affect glutathione S-transferase or {gamma}-glutamyl transpeptidase activity. Radiation activated NF-{kappa}B was reversed by CAPE pretreatment. In vivo study revealed that pretreatment with CAPE before IR resulted in greater inhibition of tumor growth and prolongation of survival in comparison with IR alone. Pretreatment with CAPE neither affected body weights nor produced hepatic, renal, or hematopoietic toxicity. Conclusions: CAPE sensitizes CT26 colorectal adenocarcinoma to IR, which may be via depleting GSH and inhibiting NF-{kappa}B activity, without toxicity to bone marrow, liver, and kidney.« less

Biological Responses of the American Coot (Fulica americana), in wetlands with contrasting environmental conditions (Basin of México).

PubMed

López-Islas, María Eugenia; Ibarra-Meza, Itzel; Ortiz-Ordóñez, Esperanza; Favari, Liliana; Elías Sedeño-Díaz, J; López-López, Eugenia

2017-01-01

Wetland ecosystems are subject to severe impacts (physical and chemical) and to the input of various xenobiotics that provoke toxicological consequences. Waterbirds are potential sentinel species of these environments. To analyze how habitat conditions affect the health of Fulica americana, early-warning biomarkers, histopathology, somatic indices, and water quality were examined in two wetlands of the Basin of Mexico: Xochimilco, an urban wetland highly eutrophic with a mixture of pollutants, and Tecocomulco (the reference site), a rural wetland with hunting migratory birds in winter, and with some agricultural contaminants. Coots were collected over 1 year, and the birds were aged, eviscerated, and weighed. Liver samples were analyzed biochemically and histologically. Biomarkers revealed that coots displayed higher lipid peroxidation and elevated activities of gamma-glutamyl transferase and alanine aminotransferase, suggesting hepatic damage during autumn and winter. In Tecocomulco, coots during winter has the highest thiobarbituric acid reactive substances (as a measure of oxidative stress), which may be associated with the presence of predators. In Tecocomulco, the higher gonadosomatic index was detected in spring and summer, while in Xochimilco it was elevated in summer, indicating a delayed egg laying and reproduction in coots from the latter study site. In both wetlands, leukocyte infiltration, alone or combined with vasocongestion, reflected alterations in the inflammatory processes in liver throughout the annual cycle and thus potentially altered hepatic function and organism survival. In both wetlands, coots were permanent residents and chronically exposed to different stressors, suggesting damage may be irreversible with potentially adversely reproductive consequences.

Metabolic syndrome indicators and target organ damage in urban active coping African and Caucasian men: the SABPA study.

PubMed

de Kock, A; Malan, L; Potgieter, J C; Steenekamp, W; van der Merwe, M T

2012-05-01

Psychosocial stress relating to an urban environment or acculturation increases the prevalence of metabolic syndrome (MetS). The objectives of this study were firstly to indicate and compare differences regarding appraisal of stress or active coping responses in urban African (n=88) and Caucasian (n=101) male teachers of South Africa, in accord with the prevalence of MetS indicators. And secondly to investigate the extent to which utilisation of active coping responses, together with MetS indicators, predict target organ damage, in these men. The Coping Strategy Indicator determined high and low active coping responses in male teachers from the Sympathetic Activity and Ambulatory Blood Pressure in Africans (SABPA) study. SABPA inclusion and exclusion criteria were used. Additionally, diabetic medication users (n=8), and participants with renal impairment (n=2) or HIV positive (n=13), were excluded. MetS indicators included glucose, triglyceride, high-density lipoprotein cholesterol, blood pressure, and waist circumference, independent of confounders (age, physical activity, gamma glutamyl transferase). Microalbuminuria and carotid intima-media thickness indicated target organ damage. More MetS indicators exceeded the IDF cut-off points in high active coping African men (14.71%) than in their Caucasian counterparts (3.33%), as determined from χ² analyses. Furthermore, stepwise regressions indicated that more MetS indicators predicted endothelial dysfunction, especially in the high active coping African men. High active coping African men showed more manifestation of MetS, compared to their Caucasian counterparts, and revealed progress towards endothelial dysfunction. © J. A. Barth Verlag in Georg Thieme Verlag KG Stuttgart · New York.

Plasma chemistry in peregrine falcons (Falco peregrinus): Reference values and physiological variations of importance for interpretation.

PubMed

Lumeij, J T; Remple, J D; Remple, C J; Riddle, K E

1998-01-01

Reference values (inner limits of the percentiles P(2.5) and P(97.5) are given with a probability of 95%) for 21 plasma chemical variables were established in 79 peregrine falcons (Falco peregrinus). The following values were established: urea 0.8 to 3.9 mmol/l, creatinine 24 to 64 mumol/l, glucose 16.5 to 22.0 mmol/l, sodium 150 to 170 mmol/l, chloride 114 to 131 mmol/I, inorganic phosphorus 0.55 to 1.53 mmol/l, osmolal-ity 322 to 356 mOsmol/kg, alkaline phosphatase 31 to 121 IU/l, alanine aminotransferase 29 to 90 IU/l, aspartate aminotransferase 34 to 116 U/l, gamma glutamyl transferase 0 to 3 IU/l, lactate dehydrogenase 1008 to 2650 IU/l, creatine kinase 120 to 442 IU/l, cholinesterase 143 to 325 IU/1, glutamate dehydrogenase < 8 IU/l, total bile acids 5 to 69 mumol/l, uric acid 253 to 995 mumol/l, total protein 24 to 39 g/l, albumin 12.7 to 22.4 g/l. Reference values for the calculated albumin/globulin (A/G) ratio were 0.8 to 24. Based on previous studies, reference values for calcium were established using an adjustment formula using plasma total protein concentrations (before correction 1.86 to 2.49, after correction 1.97 to 2.46 mmol/l). Results of plasma potassium concentrations were erratic which was shown to be due to a time lag between sample collection and separation of plasma and cells.

Study of new ways of supplementary and combinatory therapy of rheumatoid arthritis with immunomodulators. Glucomannan and Imunoglukán in adjuvant arthritis.

PubMed

Bauerová, K; Paulovicová, E; Mihalová, D; Svík, K; Ponist, S

2009-01-01

We studied the anti-arthritic activity of glucomannan (GM) isolated from Candida utilis and of Imunoglukán, a beta-(1,3/1,6)-D-glucan (IMG) isolated from Pleurotus ostreatus. Adjuvant arthritis (AA) was induced intradermally by the injection of Mycobacterium butyricum in incomplete Freund's adjuvant to Lewis rats. Blood for biochemical and immunological analysis was collected on experimental days 1, 14, 21, and 28. A clinical parameter--hind paw volume (HPV)--was also measured. The detection of IL-1 alpha, IL-4, TNF alpha, and MCP-1 was done by immunoflowcytometry. On day 28--the end of the experiment--we determined spectrophotometrically: the total anti-oxidant status (TAS) of plasma samples along with thiobarbituric acid-reacting substances (TBARS) levels in plasma and we assessed the activity of gamma-glutamyl transferase (GGT) in hind paw joint homogenate. The experiments included healthy animals, arthritic animals without treatment, and arthritic animals with administration of glucomannan (GM-AA) in the oral daily dose of 15 mg/kg b.w. and of IMG (IMG-AA) in the oral daily dose of 2 mg/kg b.w. The progress of AA was manifested by all parameters monitored. Both substances had beneficial effects on HPV, TBARS levels, GGT activity, and TAS levels. For cytokine assessment, only IMG-AA samples were selected, considering the significant HPV improvement accompanied with the observed anti-oxidant action. IMG administration had a positive immunomodulating effect on all cytokine plasma levels measured, changed markedly due to arthritis progression. Thus, IMG may be considered as a candidate for combinatorial therapy of rheumatoid arthritis.

Prophylactic role of phycocyanin: a study of oxalate mediated renal cell injury.

PubMed

Farooq, Shukkur Muhammed; Asokan, Devarajan; Kalaiselvi, Periandavan; Sakthivel, Ramasamy; Varalakshmi, Palaninathan

2004-08-10

Oxalate induced renal calculi formation and the associated renal injury is thought to be caused by free radical mediated mechanisms. An in vivo model was used to investigate the effect of phycocyanin (from Spirulina platensis), a known antioxidant, against calcium oxalate urolithiasis. Male Wistar rats were divided into four groups. Hyperoxaluria was induced in two of these groups by intraperitoneal infusion of sodium oxalate (70 mg/kg) and a pretreatment of phycocyanin (100 mg/kg) as a single oral dosage was given, 1h prior to sodium oxalate infusion. An untreated control and drug control (phycocyanin alone) were also included in the study. We observed that phycocyanin significantly controlled the early biochemical changes in calcium oxalate stone formation. The antiurolithic nature of the drug was evaluated by the assessment of urinary risk factors and light microscopic observation of urinary crystals. Renal tubular damage as divulged by urinary marker enzymes (alkaline phosphatase, acid phosphatase and gamma-glutamyl transferase) and histopathological observations such as decreased tubulointerstitial, tubular dilatation and mononuclear inflammatory cells, indicated that renal damage was minimised in drug-pretreated group. Oxalate levels (P < 0.001) and lipid peroxidation (P < 0.001) in kidney tissue were significantly controlled by drug pretreatment, suggesting the ability of phycocyanin to quench the free radicals, thereby preventing the lipid peroxidation mediated tissue damage and oxalate entry. This accounts for the prevention of CaOx stones. Thus, the present analysis revealed the antioxidant and antiurolithic potential of phycocyanin thereby projecting it as a promising therapeutic agent against renal cell injury associated kidney stone formation.

Retinopathy in non diabetics, diabetic retinopathy and oxidative stress: a new phenotype in Central Africa?

PubMed

Longo-Mbenza, Benjamin; Mvitu Muaka, Moise; Masamba, Wayiza; Muizila Kini, Lucien; Longo Phemba, Igor; Kibokela Ndembe, Dalida; Tulomba Mona, Doris

2014-01-01

To evaluate the rates of retinopathy without diabetes and diabetic retinopathy (DR), associated with some markers of oxidative stress, antioxidants and cardiometabolic risk factors. We determined the prevalence of DR in 150 type 2 diabetes mellitus (T2DM) patients, that of retinopathy in 50 non diabetics, the levels of body mass index (BMI), waist circumference (WC), blood pressure, lipids, 8-isoprostane, 8-hydroxydeoxyguanosine (8-OHdG), gamma-glutamyl transferase GT (GGT), oxidized low-density lipoprotein (OxLDL), thiobarbituric acid reacting substances (TBARS), reduced glutathione (GSH), superoxide dismutase (SOD), uric acid, creatinine, albumin, total antioxidant status (TAOS), zinc, selenium, magnesium, vitamin C, vitamin D, vitamin E, glucose, apolipoprotein B (ApoB). The prevalences of DR at 53y and Rtp at 62y were 44% (n=66) and 10% (n=5), respectively. The highest levels of 8-isoprostane, 8-OHdG, TBARS, SOD, and OxLDL were in DR. The lowest levels of vitamin D, vitamin C, TAOS, and vitamin E were in DR. In the case-control study discriminant analysis, the levels of vitamin C, vitamin D, ApoB, 8-OHdG, creatinine, Zn, vitamin E, and WC distinguished significantly non-diabetics without DR (controls), T2DM patients without DR and T2DM patients with DR. Anticipation of DR onset is significantly associated with the exageration of oxidative stress biomarkers or decrease of antioxidants in African type 2 diabetics. Prevention of oxidative stress and abdominal obesity is needed. Supplementation in vitamin C, D, and E should be recommended as complement therapies of T2DM.

A method to describe inelastic gamma field distribution in neutron gamma density logging.

PubMed

Zhang, Feng; Zhang, Quanying; Liu, Juntao; Wang, Xinguang; Wu, He; Jia, Wenbao; Ti, Yongzhou; Qiu, Fei; Zhang, Xiaoyang

2017-11-01

Pulsed neutron gamma density logging (NGD) is of great significance for radioprotection and density measurement in LWD, however, the current methods have difficulty in quantitative calculation and single factor analysis for the inelastic gamma field distribution. In order to clarify the NGD mechanism, a new method is developed to describe the inelastic gamma field distribution. Based on the fast-neutron scattering and gamma attenuation, the inelastic gamma field distribution is characterized by the inelastic scattering cross section, fast-neutron scattering free path, formation density and other parameters. And the contribution of formation parameters on the field distribution is quantitatively analyzed. The results shows the contribution of density attenuation is opposite to that of inelastic scattering cross section and fast-neutron scattering free path. And as the detector-spacing increases, the density attenuation gradually plays a dominant role in the gamma field distribution, which means large detector-spacing is more favorable for the density measurement. Besides, the relationship of density sensitivity and detector spacing was studied according to this gamma field distribution, therefore, the spacing of near and far gamma ray detector is determined. The research provides theoretical guidance for the tool parameter design and density determination of pulsed neutron gamma density logging technique. Copyright © 2017 Elsevier Ltd. All rights reserved.

Aedes aegypti juvenile hormone acid methyl transferase, the ultimate enzyme in the biosynthetic pathway of juvenile hormone III, exhibits substrate control

USDA-ARS?s Scientific Manuscript database

We report on the cloning, sequencing, characterization, 3D modeling and docking of Aedes aegypti juvenile hormone acid methyl transferase (AeaJHAMT), the enzyme that converts juvenile hormone acid (JHA) into juvenile hormone (JH). Purified recombinant AeaJHAMT was extensively characterized for enzym...

Osteoblast-Specific γ-Glutamyl Carboxylase-Deficient Mice Display Enhanced Bone Formation With Aberrant Mineralization.

PubMed

Azuma, Kotaro; Shiba, Sachiko; Hasegawa, Tomoka; Ikeda, Kazuhiro; Urano, Tomohiko; Horie-Inoue, Kuniko; Ouchi, Yasuyoshi; Amizuka, Norio; Inoue, Satoshi

2015-07-01

Vitamin K is a fat-soluble vitamin that is necessary for blood coagulation. In addition, it has bone-protective effects. Vitamin K functions as a cofactor of γ-glutamyl carboxylase (GGCX), which activates its substrates by carboxylation. These substrates are found throughout the body and examples include hepatic blood coagulation factors. Furthermore, vitamin K functions as a ligand of the nuclear receptor known as steroid and xenobiotic receptor (SXR) and its murine ortholog, pregnane X receptor (PXR). We have previously reported on the bone-protective role of SXR/PXR signaling by demonstrating that systemic Pxr-knockout mice displayed osteopenia. Because systemic Ggcx-knockout mice die shortly after birth from severe hemorrhage, the GGCX-mediated effect of vitamin K on bone metabolism has been difficult to evaluate. In this work, we utilized Ggcx-floxed mice to generate osteoblast-specific GGCX-deficient (Ggcx(Δobl/Δobl)) mice by crossing them with Col1-Cre mice. The bone mineral density (BMD) of Ggcx(Δobl/Δobl) mice was significantly higher than that of control Col1-Cre (Ggcx(+/+)) mice. Histomorphometrical analysis of trabecular bones in the proximal tibia showed increased osteoid volume and a higher rate of bone formation in Ggcx(Δobl/Δobl) mice. Histomorphometrical analysis of cortical bones revealed a thicker cortical width and a higher rate of bone formation in Ggcx(Δobl/Δobl) mice. Electron microscopic examination revealed disassembly of mineralized nodules and aberrant calcification of collagen fibers in Ggcx(Δobl/Δobl) mice. The mechanical properties of bones from Ggcx(Δobl/Δobl) mice tended to be stronger than those from control Ggcx(+/+) mice. These results suggest that GGCX in osteoblasts functions to prevent abnormal mineralization in bone formation, although this function may not be a prerequisite for the bone-protective effect of vitamin K. © 2015 American Society for Bone and Mineral Research.

The Fusarium oxysporum gnt2, Encoding a Putative N-Acetylglucosamine Transferase, Is Involved in Cell Wall Architecture and Virulence

PubMed Central

López-Fernández, Loida; Ruiz-Roldán, Carmen; Pareja-Jaime, Yolanda; Prieto, Alicia; Khraiwesh, Husam; Roncero, M. Isabel G.

2013-01-01

With the aim to decipher the molecular dialogue and cross talk between Fusarium oxysporum f.sp. lycopersci and its host during infection and to understand the molecular bases that govern fungal pathogenicity, we analysed genes presumably encoding N-acetylglucosaminyl transferases, involved in glycosylation of glycoproteins, glycolipids, proteoglycans or small molecule acceptors in other microorganisms. In silico analysis revealed the existence of seven putative N-glycosyl transferase encoding genes (named gnt) in F. oxysporum f.sp. lycopersici genome. gnt2 deletion mutants showed a dramatic reduction in virulence on both plant and animal hosts. Δgnt2 mutants had αalterations in cell wall properties related to terminal αor β-linked N-acetyl glucosamine. Mutant conidia and germlings also showed differences in structure and physicochemical surface properties. Conidial and hyphal aggregation differed between the mutant and wild type strains, in a pH independent manner. Transmission electron micrographs of germlings showed strong cell-to-cell adherence and the presence of an extracellular chemical matrix. Δgnt2 cell walls presented a significant reduction in N-linked oligosaccharides, suggesting the involvement of Gnt2 in N-glycosylation of cell wall proteins. Gnt2 was localized in Golgi-like sub-cellular compartments as determined by fluorescence microscopy of GFP::Gnt2 fusion protein after treatment with the antibiotic brefeldin A or by staining with fluorescent sphingolipid BODIPY-TR ceramide. Furthermore, density gradient ultracentrifugation allowed co-localization of GFP::Gnt2 fusion protein and Vps10p in subcellular fractions enriched in Golgi specific enzymatic activities. Our results suggest that N-acetylglucosaminyl transferases are key components for cell wall structure and influence interactions of F. oxysporum with both plant and animal hosts during pathogenicity. PMID:24416097

Acetate Utilization and Butyryl Coenzyme A (CoA):Acetate-CoA Transferase in Butyrate-Producing Bacteria from the Human Large Intestine

PubMed Central

Duncan, Sylvia H.; Barcenilla, Adela; Stewart, Colin S.; Pryde, Susan E.; Flint, Harry J.

2002-01-01

Seven strains of Roseburia sp., Faecalibacterium prausnitzii, and Coprococcus sp. from the human gut that produce high levels of butyric acid in vitro were studied with respect to key butyrate pathway enzymes and fermentation patterns. Strains of Roseburia sp. and F. prausnitzii possessed butyryl coenzyme A (CoA):acetate-CoA transferase and acetate kinase activities, but butyrate kinase activity was not detectable either in growing or in stationary-phase cultures. Although unable to use acetate as a sole source of energy, these strains showed net utilization of acetate during growth on glucose. In contrast, Coprococcus sp. strain L2-50 is a net producer of acetate and possessed detectable butyrate kinase, acetate kinase, and butyryl-CoA:acetate-CoA transferase activities. These results demonstrate that different functionally distinct groups of butyrate-producing bacteria are present in the human large intestine. PMID:12324374

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

PubMed

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

2007-08-01

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

A Xanthomonas uridine 5'-monophosphate transferase inhibits plant immune kinases.

PubMed

Feng, Feng; Yang, Fan; Rong, Wei; Wu, Xiaogang; Zhang, Jie; Chen, She; He, Chaozu; Zhou, Jian-Min

2012-04-15

Plant innate immunity is activated on the detection of pathogen-associated molecular patterns (PAMPs) at the cell surface, or of pathogen effector proteins inside the plant cell. Together, PAMP-triggered immunity and effector-triggered immunity constitute powerful defences against various phytopathogens. Pathogenic bacteria inject a variety of effector proteins into the host cell to assist infection or propagation. A number of effector proteins have been shown to inhibit plant immunity, but the biochemical basis remains unknown for the vast majority of these effectors. Here we show that the Xanthomonas campestris pathovar campestris type III effector AvrAC enhances virulence and inhibits plant immunity by specifically targeting Arabidopsis BIK1 and RIPK, two receptor-like cytoplasmic kinases known to mediate immune signalling. AvrAC is a uridylyl transferase that adds uridine 5'-monophosphate to and conceals conserved phosphorylation sites in the activation loop of BIK1 and RIPK, reducing their kinase activity and consequently inhibiting downstream signalling.

Glutathione S-transferase mediates an ageing response to mitochondrial dysfunction

PubMed Central

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

2016-01-01

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

O-GlcNAc transferase inhibitors: current tools and future challenges.

PubMed

Trapannone, Riccardo; Rafie, Karim; van Aalten, Daan M F

2016-02-01

The O-linked N-acetylglucosamine (O-GlcNAc) post-translational modification (O-GlcNAcylation) is the dynamic and reversible attachment of N-acetylglucosamine to serine and threonine residues of nucleocytoplasmic target proteins. It is abundant in metazoa, involving hundreds of proteins linked to a plethora of biological functions with implications in human diseases. The process is catalysed by two enzymes: O-GlcNAc transferase (OGT) and O-GlcNAcase (OGA) that add and remove sugar moieties respectively. OGT knockout is embryonic lethal in a range of animal models, hampering the study of the biological role of O-GlcNAc and the dissection of catalytic compared with non-catalytic roles of OGT. Therefore, selective and potent chemical tools are necessary to inhibit OGT activity in the context of biological systems. The present review focuses on the available OGT inhibitors and summarizes advantages, limitations and future challenges. © 2016 Authors; published by Portland Press Limited.

Chloroplast SRP43 acts as a chaperone for glutamyl-tRNA reductase, the rate-limiting enzyme in tetrapyrrole biosynthesis.

PubMed

Wang, Peng; Liang, Fu-Cheng; Wittmann, Daniel; Siegel, Alex; Shan, Shu-Ou; Grimm, Bernhard

2018-04-10

Assembly of light-harvesting complexes requires synchronization of chlorophyll (Chl) biosynthesis with biogenesis of light-harvesting Chl a/b-binding proteins (LHCPs). The chloroplast signal recognition particle (cpSRP) pathway is responsible for transport of nucleus-encoded LHCPs in the stroma of the plastid and their integration into the thylakoid membranes. Correct folding and assembly of LHCPs require the incorporation of Chls, whose biosynthesis must therefore be precisely coordinated with membrane insertion of LHCPs. How the spatiotemporal coordination between the cpSRP machinery and Chl biosynthesis is achieved is poorly understood. In this work, we demonstrate a direct interaction between cpSRP43, the chaperone that mediates LHCP targeting and insertion, and glutamyl-tRNA reductase (GluTR), a rate-limiting enzyme in tetrapyrrole biosynthesis. Concurrent deficiency for cpSRP43 and the GluTR-binding protein (GBP) additively reduces GluTR levels, indicating that cpSRP43 and GBP act nonredundantly to stabilize GluTR. The substrate-binding domain of cpSRP43 binds to the N-terminal region of GluTR, which harbors aggregation-prone motifs, and the chaperone activity of cpSRP43 efficiently prevents aggregation of these regions. Our work thus reveals a function of cpSRP43 in Chl biosynthesis and suggests a striking mechanism for posttranslational coordination of LHCP insertion with Chl biosynthesis.

The gamma cycle.

PubMed

Fries, Pascal; Nikolić, Danko; Singer, Wolf

2007-07-01

Activated neuronal groups typically engage in rhythmic synchronization in the gamma-frequency range (30-100 Hz). Experimental and modeling studies demonstrate that each gamma cycle is framed by synchronized spiking of inhibitory interneurons. Here, we review evidence suggesting that the resulting rhythmic network inhibition interacts with excitatory input to pyramidal cells such that the more excited cells fire earlier in the gamma cycle. Thus, the amplitude of excitatory drive is recoded into phase values of discharges relative to the gamma cycle. This recoding enables transmission and read out of amplitude information within a single gamma cycle without requiring rate integration. Furthermore, variation of phase relations can be exploited to facilitate or inhibit exchange of information between oscillating cell assemblies. The gamma cycle could thus serve as a fundamental computational mechanism for the implementation of a temporal coding scheme that enables fast processing and flexible routing of activity, supporting fast selection and binding of distributed responses. This review is part of the INMED/TINS special issue Physiogenic and pathogenic oscillations: the beauty and the beast, based on presentations at the annual INMED/TINS symposium (http://inmednet.com).

Endothelial cell palmitoylproteomics identifies novel lipid modified targets and potential substrates for protein acyl transferases

PubMed Central

Marin, Ethan P.; Derakhshan, Behrad; Lam, TuKiet T.; Davalos, Alberto; Sessa, William C.

2012-01-01

Rationale Protein S-palmitoylation is the post-translational attachment of a saturated 16-carbon palmitic acid to a cysteine side chain via a thioester bond. Palmitoylation can affect protein localization, trafficking, stability, and function. The extent and roles of palmitoylation in endothelial cell (EC) biology is not well understood, in part due to technological limits on palmitoylprotein detection. Objective To develop a method using acyl-biotinyl exchange (ABE) technology coupled with mass spectrometry to globally isolate and identify palmitoylproteins in EC. Methods and Results More than 150 putative palmitoyl proteins were identified in EC using ABE and mass spectrometry. Among the novel palmitoylproteins identified is superoxide dismutase 1 (SOD1), an intensively studied enzyme that protects all cells from oxidative damage. Mutation of cysteine 6 prevents palmitoylation, leads to reduction in SOD1 activity in vivo and in vitro, and inhibits nuclear localization, thereby supporting a functional role for SOD1 palmitoylation. Moreover, we used ABE to search for substrates of particular protein acyl transferases in EC. We found that palmitoylation of the cell adhesion protein PECAM1 is dependent on the protein acyl transferase ZDHHC21. We show that knockdown of ZDHHC21 leads to reduced levels of PECAM1 at the cell surface. Conclusions Our data demonstrate the utility of EC palmitoylproteomics to reveal new insights into the role of this important post-translational lipid modification in EC biology. PMID:22496122

A Platinum-Enriched gamma+gamma' Two-Phase Bond Coat on Ni-Base Superalloys

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

Zhang, Ying; Pint, Bruce A; Haynes, James A

2005-01-01

Pt-enriched {gamma} + {gamma}{prime} two-phase coating was applied to directionally-solidified Ni-based superalloy Ren{acute e} 142 substrates with three different Hf levels (0.02, 0.76, and 1.37 wt.%). The coating was prepared by electroplating a thin layer of Pt on the superalloy followed by a diffusion treatment. The as-deposited coating exhibited a {gamma} + {gamma}{prime} two-phase microstructure with a major composition of Ni-16Al-18Pt-7Cr-9Co (in at.%) along with some incorporation of refractory elements from the substrates. Cyclic oxidation testing at 1100 C in air indicated improved oxidation resistance of the Ren{acute e} 142 alloys with the Pt-enriched {gamma} + {gamma}{prime} coatings. In addition,more » the oxidation resistance of both uncoated and coated alloys was proportional to the Hf content in the substrate. Compared with the single-phase {beta}-(Ni,Pt)Al coating, slightly higher mass gains and localized spallation were observed on the {gamma} + {gamma}{prime} two-phase coating, which might be due to the segregation of refractory elements and high sulfur levels in these superalloy substrates.« less

Gamma ray transients

NASA Technical Reports Server (NTRS)

Cline, Thomas L.

1987-01-01

The discovery of cosmic gamma ray bursts was made with systems designed at Los Alamos Laboratory for the detection of nuclear explosions beyond the atmosphere. HELIOS-2 was the first gamma ray burst instrument launched; its initial results in 1976, seemed to deepen the mystery around gamma ray transients. Interplanetary spacecraft data were reviewed in terms of explaining the behavior and source of the transients.

Expression of peroxisome proliferator-activated receptor gamma (PPAR-gamma) in canine nasal carcinomas.

PubMed

Paciello, O; Borzacchiello, G; Varricchio, E; Papparella, S

2007-10-01

Peroxisome proliferator-activated receptor gamma (PPAR-gamma) is a ligand-activated transcriptional factor belonging to the steroid receptor superfamily. PPAR-gamma is expressed in multiple normal and neoplastic tissues, such as the breast, colon, lung, ovary and placenta. In addition to adipogenic and anti-inflammatory effects, PPAR-gamma activation has been shown to be anti-proliferative by its differentiation-promoting effect, suggesting that activation of PPAR-gamma may be useful in slowing or arresting the proliferation of de-differentiated tumour cells. In this study, we investigated the expression of PPAR-gamma in normal and neoplastic canine nasal epithelium. Twenty-five samples composed of five normal nasal epithelia and 20 canine nasal carcinomas, were immunohistochemically stained for PPAR-gamma. The specificity of the antibody was verified by Western Blot analysis. Confocal laser scanning microscopical investigation was also performed. In normal epithelium, the staining pattern was cytoplasmic and polarized at the cellular free edge. In carcinomas, the neoplastic cells showed mainly strong cytoplasmatic PPAR-gamma expression; moreover, perinuclear immunoreactivity was also detected and few neoplastic cells exhibited a nuclear positivity. Our results demonstrate different patterns of PPAR-gamma expression in normal canine nasal epithelium when compared with canine nasal carcinoma. The importance of this transcription factor in the pathophysiology of several different tumours has stimulated much research in this field and has opened new opportunities for the treatment of the tumours.

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

PubMed

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

2015-03-01

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

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

PubMed Central

Sytykiewicz, Hubert

2011-01-01

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

Cloning, sequencing and expression of white rhinoceros (Ceratotherium simum) interferon-gamma (IFN-gamma) and the production of rhinoceros IFN-gamma specific antibodies.

PubMed

Morar, D; Tijhaar, E; Negrea, A; Hendriks, J; van Haarlem, D; Godfroid, J; Michel, A L; Rutten, V P M G

2007-01-15

Bovine tuberculosis (BTB) is endemic in African buffalo (Syncerus caffer) in the Kruger National Park (KNP). In addition to buffalo, Mycobacterium bovis has been found in at least 14 other mammalian species in South Africa, including kudu (Tragelaphus strepsiceros), Chacma baboon (Papio ursinus) and lion (Panthera leo). This has raised concern about the spillover into other potentially susceptible species like rhinoceros, thus jeopardising breeding and relocation projects aiming at the conservation of biodiversity. Hence, procedures to screen for and diagnose BTB in black rhinoceros (Diceros bicornis) and white rhinoceros (Ceratotherium simum) need to be in place. The Interferon-gamma (IFN-gamma) assay is used as a routine diagnostic tool to determine infection of cattle and recently African buffalo, with M. bovis and other mycobacteria. The aim of the present work was to develop reagents to set up a rhinoceros IFN-gamma (RhIFN-gamma) assay. The white rhinoceros IFN-gamma gene was cloned, sequenced and expressed as a mature protein. Amino acid (aa) sequence analysis revealed that RhIFN-gamma shares a homology of 90% with equine IFN-gamma. Monoclonal antibodies, as well as polyclonal chicken antibodies (Yolk Immunoglobulin-IgY) with specificity for recombinant RhIFN-gamma were produced. Using the monoclonals as capture antibodies and the polyclonal IgY for detection, it was shown that recombinant as well as native white rhinoceros IFN-gamma was recognised. This preliminary IFN-gamma enzyme-linked immunosorbent assay (ELISA), has the potential to be developed into a diagnostic assay for M. bovis infection in rhinoceros.

The O-GlcNAc Transferase Intellectual Disability Mutation L254F Distorts the TPR Helix.

PubMed

Gundogdu, Mehmet; Llabrés, Salomé; Gorelik, Andrii; Ferenbach, Andrew T; Zachariae, Ulrich; van Aalten, Daan M F

2018-05-17

O-linked β-N-acetyl- D -glucosamine (O-GlcNAc) transferase (OGT) regulates protein O-GlcNAcylation, an essential post-translational modification that is abundant in the brain. Recently, OGT mutations have been associated with intellectual disability, although it is not understood how they affect OGT structure and function. Using a multi-disciplinary approach we show that the L254F OGT mutation leads to conformational changes of the tetratricopeptide repeats and reduced activity, revealing the molecular mechanisms contributing to pathogenesis. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

Fucosylation of xyloglucan: localization of the transferase in dictyosomes of pea stem cells. [Pisum sativum

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

Camirand, A.; Brummell, D.; MacLachlan, G.

1987-07-01

Microsomal membranes from elongating regions of etiolated Pisum sativum stems were separated by rate-zonal centrifugation on Renografin gradients. The transfer of labeled fucose and xylose from GDP-(/sup 14/C) fucose and UDP-(/sup 14/C)xylose to xyloglucan occurred mainly in dictyosome-enriched fractions. No transferase activity was detected in secretory vesicle fractions. Pulse-chase experiments using pea stem slices incubated with (/sup 3/H)fucose suggest that xyloglucan chains are fucosylated and their structure completed within the dictyosomes, before being transported to the cell wall by secretory vesicles.

Association of canalicular membrane enzymes with bile acid micelles and lipid aggregates in human and rat bile.

PubMed

Accatino, L; Pizarro, M; Solís, N; Koenig, C S

1995-01-18

This study was undertaken to gain insights into the characteristics of the polymolecular association between canalicular membrane enzymes, bile acids, cholesterol and phospholipids in bile and into the celular mechanisms whereby the enzymes are secreted into bile. With this purpose, we studied the distribution of bile acids, cholesterol, phospholipids, proteins and representative canalicular membrane enzymes (alkaline phosphatase, 5'-nucleotidase and gamma-glutamyl transpeptidase), which can be considered specific marker constituents, in bile fractions enriched in phospholipid-cholesterol lamellar structures (multilamellar and unilamellar vesicles) and bile acid-mixed micelles. These fractions were isolated by ultracentrifugation from human hepatic bile, normal rat bile and bile of rats treated with diosgenin, a steroid that induces a marked increase in biliary cholesterol secretion, and were characterized by density, lipid composition and transmission electron microscopy. These studies demonstrate that alkaline phosphatase, 5'-nucleotidase and gamma-glutamyl transpeptidase are secreted into both human and rat bile where they are preferentially associated with bile acid-mixed micelles, suggesting a role for bile acids in both release of these enzymes and lipids from the canalicular membrane and solubilization in bile. In addition, heterogeneous association of these enzymes with nonmicellar, lamellar structures in human and rat bile is consistent with the hypothesis that processes independent of the detergent effects of bile acids might also result in the release of specific intrinsic membrane proteins into bile.

Nigella sativa (black cumin) ameliorates potassium bromate-induced early events of carcinogenesis: diminution of oxidative stress.

PubMed

Khan, Naghma; Sharma, Sonia; Sultana, Sarwat

2003-04-01

Potassium bromate (KBrO3) is a potent nephrotoxic agent. In this paper, we report the chemopreventive effect of Nigella sativa (black cumin) on KBrO3-mediated renal oxidative stress, toxicity and tumor promotion response in rats. KBrO3 (125 mg/kg body weight, intraperitoneally) enhances lipid peroxidation, gamma-glutamyl transpeptidase, hydrogen peroxide and xanthine oxidase with reduction in the activities of renal antioxidant enzymes and renal glutathione content. A marked increase in blood urea nitrogen and serum creatinine has also been observed. KBrO3 treatment also enhances ornithine decarboxylase (ODC) activity and [3H] thymidine incorporation into renal DNA. Prophylaxis of rats orally with Nigella sativa extract (50 mg/kg body weight and 100 mg/kg body weight) resulted in a significant decrease in renal microsomal lipid peroxidation (P < 0.001), gamma-glutamyl transpeptidase (P < 0.001), H2O2 (P < 0.001) and xanthine oxidase (P < 0.05). There was significant recovery of renal glutathione content (P < 0.01) and antioxidant enzymes (P < 0.001). There was also reversal in the enhancement of blood urea nitrogen, serum creatinine, renal ODC activity and DNA synthesis (P < 0.001). Data suggest that Nigella sativa is a potent chemopreventive agent and may suppress KBrO3-mediated renal oxidative stress, toxicity and tumour promotion response in rats.

Measurements of the $$\\mathrm{ pp \\to W \\gamma\\gamma }$$ and $$\\mathrm{ pp \\to Z \\gamma\\gamma }$$ cross sections and limits on anomalous quartic gauge couplings at $$\\sqrt{s} =$$ 8 TeV

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

Sirunyan, A. M.; Tumasyan, A.; Adam, W.

Here, measurements are presented ofmore » $$ \\mathrm{ W \\gamma\\gamma } $$ and $$ \\mathrm{ Z \\gamma\\gamma } $$ production in proton-proton collisions. Fiducial cross sections are reported based on a data sample corresponding to an integrated luminosity of 19.4 fb$$^{-1}$$ collected with the CMS detector at a center-of-mass energy of 8 TeV. Signal is identified through the $$\\mathrm{ W } \\to \\ell\

Measurements of the $$\\mathrm{ pp \\to W \\gamma\\gamma }$$ and $$\\mathrm{ pp \\to Z \\gamma\\gamma }$$ cross sections and limits on anomalous quartic gauge couplings at $$\\sqrt{s} =$$ 8 TeV

DOE PAGES

Sirunyan, A. M.; Tumasyan, A.; Adam, W.; ...

2017-10-11

Here, measurements are presented ofmore » $$ \\mathrm{ W \\gamma\\gamma } $$ and $$ \\mathrm{ Z \\gamma\\gamma } $$ production in proton-proton collisions. Fiducial cross sections are reported based on a data sample corresponding to an integrated luminosity of 19.4 fb$$^{-1}$$ collected with the CMS detector at a center-of-mass energy of 8 TeV. Signal is identified through the $$\\mathrm{ W } \\to \\ell\

Basics of Gamma Ray Detection

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

Stinnett, Jacob; Venkataraman, Ram

The objective of this training is to explain the origin of x-rays and gamma rays, gamma ray interactions with matter, detectors and electronics used in gamma ray-spectrometry, and features of a gamma-ray spectrum for nuclear material that is safeguarded.

Dynamic gamma knife radiosurgery

NASA Astrophysics Data System (ADS)

Luan, Shuang; Swanson, Nathan; Chen, Zhe; Ma, Lijun

2009-03-01

Gamma knife has been the treatment of choice for various brain tumors and functional disorders. Current gamma knife radiosurgery is planned in a 'ball-packing' approach and delivered in a 'step-and-shoot' manner, i.e. it aims to 'pack' the different sized spherical high-dose volumes (called 'shots') into a tumor volume. We have developed a dynamic scheme for gamma knife radiosurgery based on the concept of 'dose-painting' to take advantage of the new robotic patient positioning system on the latest Gamma Knife C™ and Perfexion™ units. In our scheme, the spherical high dose volume created by the gamma knife unit will be viewed as a 3D spherical 'paintbrush', and treatment planning reduces to finding the best route of this 'paintbrush' to 'paint' a 3D tumor volume. Under our dose-painting concept, gamma knife radiosurgery becomes dynamic, where the patient moves continuously under the robotic positioning system. We have implemented a fully automatic dynamic gamma knife radiosurgery treatment planning system, where the inverse planning problem is solved as a traveling salesman problem combined with constrained least-square optimizations. We have also carried out experimental studies of dynamic gamma knife radiosurgery and showed the following. (1) Dynamic gamma knife radiosurgery is ideally suited for fully automatic inverse planning, where high quality radiosurgery plans can be obtained in minutes of computation. (2) Dynamic radiosurgery plans are more conformal than step-and-shoot plans and can maintain a steep dose gradient (around 13% per mm) between the target tumor volume and the surrounding critical structures. (3) It is possible to prescribe multiple isodose lines with dynamic gamma knife radiosurgery, so that the treatment can cover the periphery of the target volume while escalating the dose for high tumor burden regions. (4) With dynamic gamma knife radiosurgery, one can obtain a family of plans representing a tradeoff between the delivery time and the

The use of iohexol in pediatric urography: a comparative study with meglumine diatrizoate.

PubMed

Bani, E; Federighi, F; Ghio, R; Marchitiello, M; Galigani, P; Palla, R

1985-01-01

In a prospective study the nephrotoxicity of iohexol, a new non-ionic contrast medium, was compared with meglumine diatrizoate. Plasma creatinine, BUN, creatinine clearance, urinalysis and the urinary excretion of N-acetyl glucosaminidase (NAG), gamma glutamyl transpeptidase (GGT) and muramidase (MU) were determined prior to and following intravenous pyelography. A significant rise in the enzyme excretion was observed in patients who received iohexol and diatrizoate. Statistical analysis failed to demonstrate any difference in nephrotoxicity between the two iodinated contrast media.

Galactic plane gamma-radiation

NASA Technical Reports Server (NTRS)

Hartman, R. C.; Kniffen, D. A.; Thompson, D. J.; Fichtel, C. E.; Ogelman, H. B.; Tumer, T.; Ozel, M. E.

1979-01-01

Analysis of the SAS 2 data together with the COS B results shows that the distribution of galactic gamma-radiation has several similarities to that of other large-scale tracers of galactic structure. The radiation is primarily confined to a thin disc which exhibits offsets from b = 0 degrees similar to warping at radio frequencies. The principal distinction of the gamma-radiation is a stronger contrast in intensity between the region from 310 to 45 degrees in longitude and the regions away from the center that can be attributed to a variation in cosmic-ray density as a function of position in Galaxy. The diffuse galactic gamma-ray energy spectrum shows no significant variation in direction, and the spectrum seen along the plane is the same as that for the galactic component of the gamma-radiation at high altitudes. The uniformity of the galactic gamma-ray spectrum, the smooth decrease in intensity as a function of altitude, and the absence of any galactic gamma-ray sources at high altitudes indicate a diffuse origin for bulk of the galactic gamma-radiation rather than a collection of localized sources.

Gamma-ray burster recurrence timescales

NASA Technical Reports Server (NTRS)

Schaefer, B. E.; Cline, T. L.

1984-01-01

Three optical transients have been found which are associated with gamma-ray bursters (GRBs). The deduced recurrence timescale for these optical transients (tau sub opt) will depend on the minimum brightness for which a flash would be detected. A detailed analysis using all available data of tau sub opt as a function of E(gamma)/E(opt) is given. For flashes similar to those found in the Harvard archives, the best estimate of tau sub opt is 0.74 years, with a 99% confidence interval from 0.23 years to 4.7 years. It is currently unclear whether the optical transients from GRBs also give rise to gamma-ray events. One way to test this association is to measure the recurrence timescale of gamma-ray events tau sub gamma. A total of 210 gamma-ray error boxes were examined and it was found that the number of observed overlaps is not significantly different from the number expected from chance coincidence. This observation can be used to place limits on tau sub gamma for an assumed luminosity function. It was found that tau sub gamma is approx. 10 yr if bursts are monoenergetic. However, if GRBs have a power law luminosity function with a wide dynamic range, then the limit is tau sub gamma 0.5 yr. Hence, the gamma-ray data do not require tau sub gamma and tau sub opt to be different.

Recombinant human dihydroxyacetonephosphate acyl-transferase characterization as an integral monotopic membrane protein.

PubMed

Piano, Valentina; Nenci, Simone; Magnani, Francesca; Aliverti, Alessandro; Mattevi, Andrea

2016-12-02

Although the precise functions of ether phospholipids are still poorly understood, significant alterations in their physiological levels are associated either to inherited disorders or to aggressive metastatic cancer. The essential precursor, alkyl-dihydroxyacetone phosphate (DHAP), for all ether phospholipids species is synthetized in two consecutive reactions performed by two enzymes sitting on the inner side of the peroxisomal membrane. Here, we report the characterization of the recombinant human DHAP acyl-transferase, which performs the first step in alkyl-DHAP synthesis. By exploring several expression systems and designing a number of constructs, we were able to purify the enzyme in its active form and we found that it is tightly bound to the membrane through the N-terminal residues. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Thio-Linked UDP–Peptide Conjugates as O-GlcNAc Transferase Inhibitors

PubMed Central

2018-01-01

O-GlcNAc transferase (OGT) is an essential glycosyltransferase that installs the O-GlcNAc post-translational modification on the nucleocytoplasmic proteome. We report the development of S-linked UDP–peptide conjugates as potent bisubstrate OGT inhibitors. These compounds were assembled in a modular fashion by photoinitiated thiol–ene conjugation of allyl-UDP and optimal acceptor peptides in which the acceptor serine was replaced with cysteine. The conjugate VTPVC(S-propyl-UDP)TA (Ki = 1.3 μM) inhibits the OGT activity in HeLa cell lysates. Linear fusions of this conjugate with cell penetrating peptides were explored as prototypes of cell-penetrant OGT inhibitors. A crystal structure of human OGT with the inhibitor revealed mimicry of the interactions seen in the pseudo-Michaelis complex. Furthermore, a fluorophore-tagged derivative of the inhibitor works as a high affinity probe in a fluorescence polarimetry hOGT assay. PMID:29723473

Gamma watermarking

DOEpatents

Ishikawa, Muriel Y.; Wood, Lowell L.; Lougheed, Ronald W.; Moody, Kenton J.; Wang, Tzu-Fang

2004-05-25

A covert, gamma-ray "signature" is used as a "watermark" for property identification. This new watermarking technology is based on a unique steganographic or "hidden writing" digital signature, implemented in tiny quantities of gamma-ray-emitting radioisotopic material combinations, generally covertly emplaced on or within an object. This digital signature may be readily recovered at distant future times, by placing a sensitive, high energy-resolution gamma-ray detecting instrument reasonably precisely over the location of the watermark, which location may be known only to the object's owner; however, the signature is concealed from all ordinary detection means because its exceedingly low level of activity is obscured by the natural radiation background (including the gamma radiation naturally emanating from the object itself, from cosmic radiation and material surroundings, from human bodies, etc.). The "watermark" is used in object-tagging for establishing object identity, history or ownership. It thus may serve as an aid to law enforcement officials in identifying stolen property and prosecuting theft thereof. Highly effective, potentially very low cost identification-on demand of items of most all types is thus made possible.

The Gamma-ray Sky with Fermi

NASA Technical Reports Server (NTRS)

Thompson, David

2012-01-01

Gamma rays reveal extreme, nonthermal conditions in the Universe. The Fermi Gamma-ray Space Telescope has been exploring the gamma-ray sky for more than four years, enabling a search for powerful transients like gamma-ray bursts, novae, solar flares, and flaring active galactic nuclei, as well as long-term studies including pulsars, binary systems, supernova remnants, and searches for predicted sources of gamma rays such as dark matter annihilation. Some results include a stringent limit on Lorentz invariance derived from a gamma-ray burst, unexpected gamma-ray variability from the Crab Nebula, a huge gamma-ray structure associated with the center of our galaxy, surprising behavior from some gamma-ray binary systems, and a possible constraint on some WIMP models for dark matter.

Gamma Ray Astronomy

NASA Technical Reports Server (NTRS)

Wu, S. T.

2000-01-01

The project has progressed successfully during this period of performance. The highlights of the Gamma Ray Astronomy teams efforts are: (1) Support daily BATSE data operations, including receipt, archival and dissemination of data, quick-look science analysis, rapid gamma-ray burst and transient monitoring and response efforts, instrument state-of-health monitoring, and instrument commanding and configuration; (2) On-going scientific analysis, including production and maintenance of gamma-ray burst, pulsed source and occultation source catalogs, gamma-ray burst spectroscopy, studies of the properties of pulsars and black holes, and long-term monitoring of hard x-ray sources; (3) Maintenance and continuous improvement of BATSE instrument response and calibration data bases; (4) Investigation of the use of solid state detectors for eventual application and instrument to perform all sky monitoring of X-Ray and Gamma sources with high sensitivity; and (5) Support of BATSE outreach activities, including seminars, colloquia and World Wide Web pages. The highlights of this efforts can be summarized in the publications and presentation list.

Gamma ray detector shield

DOEpatents

Ohlinger, R.D.; Humphrey, H.W.

1985-08-26

A gamma ray detector shield comprised of a rigid, lead, cylindrical-shaped vessel having upper and lower portions with an pneumatically driven, sliding top assembly. Disposed inside the lead shield is a gamma ray scintillation crystal detector. Access to the gamma detector is through the sliding top assembly.

Aromatic hydrocarbon pathology in fish following a large spill into the Nemadji River, Wisconsin, USA

USGS Publications Warehouse

Caldwell, C.A.

1997-01-01

On June 30, 1992, a train accident resulted in a rail car releasing 114,000 L of a complex mixture of aromatic hydrocarbons into the Nemadji River, a tributary of Lake Superior near Superior, Wisconsin (Table 1). Although the majority of the spilled material evaporated, damage to aquatic life was extensive. Several thousand fishes were killed and an inestimable number were exposed to low concentrations (< 5 mg/L) of the chemical concentrate for several weeks (Allen 1993). Fishes that survived the spill were examined within 7 days of exposure to determine the extent of injury when compared to fishes collected from the reference site. The liver, spleen, gill, and head kidney were examined for histopathology. Blood was collected to determine the severity of liver damage reflected by the presence of the serum enzymes (aspartate aminotransferase, alanine aminotransferase, and d - glutamyl transferase).

Determination of some enzymes and macro- and microelements in stallion seminal plasma and their correlations to semen quality.

PubMed

Pesch, Sandra; Bergmann, Martin; Bostedt, Hartwig

2006-07-15

Seminal plasma is very important for sperm metabolism as well as sperm function and survival and transport in the female genital tract. Analysis of enzyme activities and concentrations of elements can estimate integrity and function of sperm cell membranes. In man much data are available about biochemical analyses of seminal plasma. However, not many studies have been conducted in horses yet. We collected ejaculates from 72 stallions, measured the volume, obtained seminal plasma by centrifugation and examined spermatozoa with light microscopy for motility, concentration, for dead sperm and morphology. Of seminal plasma fluid, we measured activities of aspartate-amino-transferase (AST), gamma-glutamyl-transferase (GGT), alkaline phosphatase (AlP), acid phosphatase (AcP) and lactate-dehydrogenase (LDH) as well as concentrations of sodium (Na(+)), potassium (K(+)), total and ionised calcium (Ca(TOTAL)/Ca(2+)), magnesium (Mg(2+)), phosphate (P), chloride (Cl), copper (Cu), iron (Fe) and zinc (Zn). In addition, correlations among different parameters in light microscopy and seminal plasma were statistically examined by using the Spearman rank correlation coefficient. Median enzyme activities for AST, GGT, AlP, AcP and LDH were 80.0, 7,500, 30,200, 20.0, 81.0 IU/L, respectively. Concentrations of Na(+), K(+), Ca(TOTAL), Ca(2+), Mg(2+), P, Cl were 110.5, 22.1, 2.9, 1.7, 3.1, 1.1 and 114.5 mmol/L, and of microelements Cu, Fe and Zn were 17.8, 1.9 and 13.2 micromol/L, respectively. Furthermore, we found significant correlations between semen volume as well as sperm concentration and AST, GGT, AlP, AcP and LDH as well as Fe and Zn. This made us propose a primary testicular and epididymal origin of these parameters. Significant correlation between GGT and motility may be a sign for its function for cell protection against free radicals. LDH activity significantly correlates with motility and progressive motility, live:dead-ratio and pathomorphology. In our study, LDH seems to

Wetting characteristics and blood clotting on surfaces of copoly(gamma-Benzyl-L-glutamate, gamma-hydroxyethyl-L-glutamine).

PubMed

Yano, E; Komai, T; Kawasaki, T; Kaifu, K; Atsuta, T; Kubo, Y; Fujiwara, Y

1985-09-01

The film surface of poly(gamma-benzyl-L-glutamate) (PBLG) was modified with 2-aminoethanol to enhance its hydrophilicity. Controlling the reaction conditions of PBLG and 2-aminoethanol, various types of copoly(gamma-benzyl-L-glutamate, gamma-hydroxyethyl-L-glutamine) film surfaces were obtained. Surface free energy (gamma sv), the dispersive component of gamma sv (gamma dsv), the nondispersive component of gamma sv (gamma psv), and the interfacial free energy of polymer surface with water (gamma sw), which were obtained by using the contact angle measurement and calculation method proposed by Andrade et al., were changed remarkably by the aminolysis. The gamma sv value increased after 2 h of aminolysis from 48.2 (PBLG) to 65.3 dyn/cm and gradually increased to around 70 dyn/cm after 12 h reaction. (gamma dsv) and (gamma psv) changed from 31.0 and 17.2 dyn/cm (PBLG) to 26.5 and 44.3 dyn/cm, respectively. These parameters of the material surfaces, modified over 12 h reaction, were found to be similar to those of the surfaces of canine aorta, vein, and human fibrin membrane. Blood clotting times on these polymer surfaces were comparatively longer than on siliconized glass surfaces.

Glutathione Transferase as a Potential Marker for Gut Epithelial Injury versus the Protective Role of Breast Milk sIgA in Infants with Rota Virus Gastroenteritis

PubMed Central

Sherif, Lobna S.; Raouf, Randaa K. Abdel; Sayede, Rokaya M. El; Wakkadd, Amany S. El; Shoaib, Ashraf R.; Ali, Hanan M.; Refay, Amira S. El

2015-01-01

BACKGROUND: Secretory immunoglobulin A (SIgA) plays an important protective role in the recognition and clearance of enteric pathogens. AIM: This study was designed to assess if mucosal integrity “measured by secretory IgA (SIgA)” is a protective factor from more epithelial alteration “measured by glutathione transferase” in infants with Rota gastroenteritis and its relation to infants’ feeding pattern. PATIENTS AND METHODS: This study was conducted on 79 infants aged 6 months and less from those diagnosed as having gastroenteritis and admitted to Gastroenteritis Department in Abo El Rish Pediatric Hospital, Cairo University. Plasma glutathione s-transferases and Stool SIgA were measured using ELISA technique. Rota virus detection was done by Reverse transcriptase PCR. RESULTS: SIgA was found to be significantly positive in exclusive breast fed infants, Glutathione transferase was significantly more frequently positive in Rota positive cases than Rota negative cases by Reverse transcriptase PCR. A significant negative correlation between Glutathione transferase and Secretory IgA was found, (p < 0.05). CONCLUSION: Breast feeding should be encouraged and highly recommended in the first two years of life as it provides Secretory IgA to breast fed infants who in turn protect them against epithelial damage caused by Rota viral gastroenteritis. PMID:27275307

A Simple Colorimetric Assay for Specific Detection of Glutathione-S Transferase Activity Associated with DDT Resistance in Mosquitoes

PubMed Central

Rajatileka, Shavanti; Steven, Andrew; Hemingway, Janet; Ranson, Hilary; Paine, Mark; Vontas, John

2010-01-01

Background Insecticide-based methods represent the most effective means of blocking the transmission of vector borne diseases. However, insecticide resistance poses a serious threat and there is a need for tools, such as diagnostic tests for resistance detection, that will improve the sustainability of control interventions. The development of such tools for metabolism-based resistance in mosquito vectors lags behind those for target site resistance mutations. Methodology/Principal Findings We have developed and validated a simple colorimetric assay for the detection of Epsilon class Glutathione transferases (GST)-based DDT resistance in mosquito species, such as Aedes aegypti, the major vector of dengue and yellow fever worldwide. The colorimetric assay is based on the specific alkyl transferase activity of Epsilon GSTs for the haloalkene substrate iodoethane, which produces a dark blue colour highly correlated with AaGSTE2-2-overexpression in individual mosquitoes. The colour can be measured visually and spectrophotometrically. Conclusions/Significance The novel assay is substantially more sensitive compared to the gold standard CDNB assay and allows the discrimination of moderate resistance phenotypes. We anticipate that it will have direct application in routine vector monitoring as a resistance indicator and possibly an important impact on disease vector control. PMID:20824165

Identification and characterization of novel peroxisome proliferator-activated receptor-gamma (PPAR-gamma) transcriptional variants in pig and human.

PubMed

Omi, T; Brenig, B; Spilar Kramer, S; Iwamoto, S; Stranzinger, G; Neuenschwander, S

2005-04-01

The peroxisome proliferator-activated receptor-gamma (PPAR-gamma) is a member of the steroid/thyroid/retinoid receptor superfamily, and is primarily expressed in fat tissue. To date, two major PPAR-gamma isoforms have been identified in pig, PPAR-gamma1 and PPAR-gamma2. Porcine PPAR-gamma1a consists of two leader exons, designated A1 and A2, followed by six exons containing the open reading frame. Here, we report the isolation and characterization of three novel PPAR-gamma1 transcripts. PPAR-gamma1b is derived from exon A1, with exon A2 spliced out. PPAR-gamma1c and PPAR-gamma1d are derived from the new exon, A', containing exon A2 (gamma1c) or without exon A2 (gamma1d). Based on PCR analysis of PAC clones that included sequences from the 5'-untranslated region of the PPAR-gamma gene, the new A' exon is located between the known exons A1 and A2. We also isolated the human homologue to exon A', as well as the two new PPAR-gamma1c and -gamma1d splice variants, from human adipose tissue. Studies of the expression of porcine PPAR-gamma by real time reverse transcription-polymerase chain reaction analysis show that transcripts derived from exon A1 were not expressed at significantly different levels in visceral fat (lamina subserosa) or subcutaneous fat (back fat, inner and outer layer). In contrast, exon A'-derived transcripts were expressed at progressively higher levels in the inner and outer layers of subcutaneous fat than in visceral fat. The same expression pattern was also observed for PPAR-gamma2. We hypothesize that there are three promoters, which differentially regulate PPAR-gamma1 and PPAR-gamma2 gene expression, depending on the specific localization of the fat tissue.

Functional Characterization of Lpt3 and Lpt6, the Inner-Core Lipooligosaccharide Phosphoethanolamine Transferases from Neisseria meningitidis▿

PubMed Central

Wenzel, Cory Q.; St. Michael, Frank; Stupak, Jacek; Li, Jianjun; Cox, Andrew D.; Richards, James C.

2010-01-01

The lipooligosaccharide (LOS) of Neisseria meningitidis contains heptose (Hep) residues that are modified with phosphoethanolamine (PEtn) at the 3 (3-PEtn) and/or 6 (6-PEtn) position. The lpt3 (NMB2010) and lpt6 (NMA0408) genes of N. meningitidis, which are proposed to encode the required HepII 3- and 6-PEtn transferases, respectively, were cloned and overexpressed as C-terminally polyhistidine-tagged fusion proteins in Escherichia coli and found to localize to the inner membrane, based on sucrose density gradient centrifugation. Lpt3-His6 and Lpt6-His6 were purified from Triton X-100-solubilized membranes by nickel chelation chromatography, and dot blot analysis of enzymatic reactions with 3-PEtn- and 6-PEtn-specific monoclonal antibodies demonstrated conclusively that Lpt3 and Lpt6 are phosphatidylethanolamine-dependent LOS HepII 3- and 6-PEtn transferases, respectively, and that both enzymes are capable of transferring PEtn to both fully acylated LOS and de-O-acylated (de-O-Ac) LOS. Further enzymatic studies using capillary electrophoresis-mass spectrometry (MS) demonstrated that both Lpt3 and Lpt6 are capable of transferring PEtn to de-O-Ac LOS molecules already containing PEtn at the 6 and 3 positions of HepII, respectively, demonstrating that there is no obligate order of PEtn addition in the generation of 3,6-di-PEtn LOS moieties in vitro. PMID:19854897

Terrestrial Gamma-Ray Flashes (TGFs)

NASA Technical Reports Server (NTRS)

Fishman, Gerald J.

2010-01-01

This slide presentation reviews the observation of Terrestrial Gamma Ray Flashes (TGFs) by Gamma-Ray Telescopes. These were: (1) BATSE /Compton Observatory, (2) Solar Spectroscopic Imager, (3) AGILE Gamma-ray Telescope, and (4) Gamma-ray Burst Monitor (GBM) on the Fermi Gamma-ray Space Telescope. It contains charts which display the counts over time, a map or the TGFs observed by the Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI). and a map showing the latitude and longitude of 85 of the TGFs observed by the Fermi GBM.

Gamma ray camera

DOEpatents

Perez-Mendez, Victor

1997-01-01

A gamma ray camera for detecting rays emanating from a radiation source such as an isotope. The gamma ray camera includes a sensor array formed of a visible light crystal for converting incident gamma rays to a plurality of corresponding visible light photons, and a photosensor array responsive to the visible light photons in order to form an electronic image of the radiation therefrom. The photosensor array is adapted to record an integrated amount of charge proportional to the incident gamma rays closest to it, and includes a transparent metallic layer, photodiode consisting of a p-i-n structure formed on one side of the transparent metallic layer, and comprising an upper p-type layer, an intermediate layer and a lower n-type layer. In the preferred mode, the scintillator crystal is composed essentially of a cesium iodide (CsI) crystal preferably doped with a predetermined amount impurity, and the p-type upper intermediate layers and said n-type layer are essentially composed of hydrogenated amorphous silicon (a-Si:H). The gamma ray camera further includes a collimator interposed between the radiation source and the sensor array, and a readout circuit formed on one side of the photosensor array.

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

PubMed

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

2017-10-01

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

Formation of gamma'-Ni3Al via the Peritectoid Reaction: gamma plus beta (+Al2O3) equals gamma'(+Al2O3)

NASA Technical Reports Server (NTRS)

Copland, Evan

2008-01-01

The activities of Al and Ni were measured using multi-cell Knudsen effusion-cell mass spectrometry (multi-cell KEMS), over the composition range 8 - 32 at.%Al and temperature range T = 1400 - 1750 K in the Ni-Al-O system. These measurements establish that equilibrium solidification of gamma'-Ni3Al-containing alloys occurs by the eutectic reaction, L (+ Al2O3) = gamma + beta (+ Al2O3), at 1640 plus or minus 1 K and a liquid composition of 24.8 plus or minus 0.2 at.%Al (at an unknown oxygen content). The {gamma + beta + Al2O3} phase field is stable over the temperature range 1633 - 1640 K, and gamma'-Ni3Al forms via the peritectiod, gamma + beta (+ Al2O3) = gamma'(+ Al2O3), at 1633 plus or minus 1 K. This behavior is inconsistent with the current Ni-Al phase diagram and a new diagram is proposed. This new Ni-Al phase diagram explains a number of unusual steady state solidification structures reported previously and provides a much simpler reaction scheme in the vicinity of the gamma'-Ni3Al phase field.

Gamma-ray astrophysics

NASA Technical Reports Server (NTRS)

Stecker, F. W. (Editor); Trombka, J. I. (Editor)

1973-01-01

Conference papers on gamma ray astrophysics are summarized. Data cover the energy region from about 0.3 MeV to a few hundred GeV and theoretical models of production mechanisms that give rise to both galactic and extragalactic gamma rays.

The Gamma-ray Universe through Fermi

NASA Technical Reports Server (NTRS)

Thompson, David J.

2012-01-01

Gamma rays, the most powerful form of light, reveal extreme conditions in the Universe. The Fermi Gamma-ray Space Telescope and its smaller cousin AGILE have been exploring the gamma-ray sky for several years, enabling a search for powerful transients like gamma-ray bursts, novae, solar flares, and flaring active galactic nuclei, as well as long-term studies including pulsars, binary systems, supernova remnants, and searches for predicted sources of gamma rays such as dark matter annihilation. Some results include a stringent limit on Lorentz invariance derived from a gamma-ray burst, unexpected gamma-ray variability from the Crab Nebula, a huge ga.nuna-ray structure associated with the center of our galaxy, surprising behavior from some gamma-ray binary systems, and a possible constraint on some WIMP models for dark matter.

Identification of a novel transposon-associated phosphoethanolamine transferase gene, mcr-5, conferring colistin resistance in d-tartrate fermenting Salmonella enterica subsp. enterica serovar Paratyphi B.

PubMed

Borowiak, Maria; Fischer, Jennie; Hammerl, Jens A; Hendriksen, Rene S; Szabo, Istvan; Malorny, Burkhard

2017-12-01

Plasmid-mediated mobilized colistin resistance is currently known to be caused by phosphoethanolamine transferases termed MCR-1, MCR-2, MCR-3 and MCR-4. However, this study focuses on the dissection of a novel resistance mechanism in mcr-1-, mcr-2- and mcr-3-negative d-tartrate fermenting Salmonella enterica subsp. enterica serovar Paratyphi B (Salmonella Paratyphi B dTa+) isolates with colistin MIC values >2 mg/L. A selected isolate from the strain collection of the German National Reference Laboratory for Salmonella was investigated by WGS and bioinformatical analysis to identify novel phosphoethanolamine transferase genes involved in colistin resistance. Subsequently PCR screening, S1-PFGE and DNA-DNA hybridization were performed to analyse the prevalence and location of the identified mcr-5 gene. Cloning and transformation experiments in Escherichia coli DH5α and Salmonella Paratyphi B dTa+ control strains were carried out and the activity of MCR-5 was determined in vitro by MIC testing. In this study, we identified a novel phosphoethanolamine transferase in 14 mcr-1-, mcr-2- and mcr-3-negative Salmonella Paratyphi B dTa+ isolates with colistin MIC values >2 mg/L that were received during 2011-13. The respective gene, further termed as mcr-5 (1644 bp), is part of a 7337 bp transposon of the Tn3 family and usually located on related multi-copy ColE-type plasmids. Interestingly, in one isolate an additional subclone with a chromosomal location of the mcr-5 transposon was observed. Our findings suggest that the transfer of colistin-resistance-mediating phosphoethanolamine transferase genes from bacterial chromosomes to mobile genetic elements has occurred in multiple independent events raising concern regarding their variety, prevalence and impact on public health. © The Author 2017. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Orotate phosphoribosyl transferase mRNA expression and the response of cholangiocarcinoma to 5-fluorouracil

PubMed Central

Hahnvajanawong, Chariya; Chaiyagool, Jariya; Seubwai, Wunchana; Bhudhisawasdi, Vajarabhongsa; Namwat, Nisana; Khuntikeo, Narong; Sripa, Banchob; Pugkhem, Ake; Tassaneeyakul, Wichittra

2012-01-01

AIM: To determine whether expression of certain enzymes related to 5-fluorouracil (5-FU) metabolism predicts 5-FU chemosensitivity in cholangiocarcinoma (CCA). METHODS: The histoculture drug response assay (HDRA) was performed using surgically resected CCA tissues. Tumor cell viability was determined morphologically with hematoxylin and eosin- and terminal deoxynucleotide transferase-mediated dUTP nick-end labeling-stained tissues. The mRNA expression of thymidine phosphorylase (TP), orotate phosphoribosyl transferase (OPRT), thymidylate synthase (TS), and dihydropyrimidine dehydrogenase (DPD) was determined with real-time reverse transcriptase-polymerase chain reaction. The levels of gene expression and the sensitivity to 5-FU were evaluated. RESULTS: Twenty-three CCA tissues were obtained from patients who had been diagnosed with intrahepatic CCA and who underwent surgical resection at Srinagarind Hospital, Khon Kaen University from 2007 to 2009. HDRA was used to determine the response of these CCA tissues to 5-FU. Based on the dose-response curve, 200 μg/mL 5-FU was selected as the test concentration. The percentage of inhibition index at the median point was selected as the cut-off point to differentiate the responding and non-responding tumors to 5-FU. When the relationship between TP, OPRT, TS and DPD mRNA expression levels and the sensitivity of CCA tissues to 5-FU was examined, only OPRT mRNA expression was significantly correlated with the response to 5-FU. The mean expression level of OPRT was significantly higher in the responder group compared to the non-responder group (0.41 ± 0.25 vs 0.22 ± 0.12, P < 0.05). CONCLUSION: OPRT mRNA expression may be a useful predictor of 5-FU chemosensitivity of CCA. Whether OPRT mRNA could be used to predict the success of 5-FU chemotherapy in CCA patients requires confirmation in patients. PMID:22912546

Topics in gamma ray astronomy

NASA Technical Reports Server (NTRS)

Ramaty, R.; Lingenfelter, R. E.

1986-01-01

Observations of gamma rays from solar flares, gamma ray bursts, the Galactic center, galactic nucleosynthesis, SS433, and Cygnus X-3, and their effects on astrophysical problems are discussed. It is observed that gamma ray spectra from solar flares are applicable to the study of particle acceleration and confinement and the determination of chemical abundances in the solar atmosphere. The gamma ray lines from the compact galactic object SS433 are utilized to examine the acceleration of jets, and analysis of the gamma ray lines of Cygnus X-3 reveal that particles can be accelerated in compact sources to ultrahigh energies.

A study of interdiffusion in beta + gamma/gamma + gamma prime Ni-Cr-Al. M.S. Thesis. Final Report

NASA Technical Reports Server (NTRS)

Carol, L. A.

1985-01-01

Ternary diffusion in the NiCrAl system at 1200 C was studied with beta + gamma/gamma + gamma prime infinite diffusion couples. Interdiffusion resulted in the formation of complex, multiphase diffusion zones. Concentration/distance profiles for Cr and Al in the phases present in the diffusion zone were measured after 200 hr. The Ni-rich portion of the NiCrAl phase diagram (1200 C) was also determined. From these data, bulk Cr and Al profiles were calculated and translated to diffusion paths on the ternary isotherm. Growth layer kinetics of the layers present in the diffusion zone were also measured.

Neutron monitoring systems including gamma thermometers and methods of calibrating nuclear instruments using gamma thermometers

DOEpatents

Moen, Stephan Craig; Meyers, Craig Glenn; Petzen, John Alexander; Foard, Adam Muhling

2012-08-07

A method of calibrating a nuclear instrument using a gamma thermometer may include: measuring, in the instrument, local neutron flux; generating, from the instrument, a first signal proportional to the neutron flux; measuring, in the gamma thermometer, local gamma flux; generating, from the gamma thermometer, a second signal proportional to the gamma flux; compensating the second signal; and calibrating a gain of the instrument based on the compensated second signal. Compensating the second signal may include: calculating selected yield fractions for specific groups of delayed gamma sources; calculating time constants for the specific groups; calculating a third signal that corresponds to delayed local gamma flux based on the selected yield fractions and time constants; and calculating the compensated second signal by subtracting the third signal from the second signal. The specific groups may have decay time constants greater than 5.times.10.sup.-1 seconds and less than 5.times.10.sup.5 seconds.

Gamma-ray astronomy

NASA Technical Reports Server (NTRS)

Ramaty, R.; Lingenfelter, R. E.

1982-01-01

Cosmic gamma rays, the physical processes responsible for their production and the astrophysical sites from which they were seen are reported. The bulk of the observed gamma ray emission is in the photon energy range from about 0.1 MeV to 1 GeV, where observations are carried out above the atmosphere. There are also, however, gamma ray observations at higher energies obtained by detecting the Cerenkov light produced by the high energy photons in the atmosphere. Gamma ray emission was observed from sources as close as the Sun and the Moon and as distant as the quasar 3C273, as well as from various other galactic and extragalactic sites. The radiation processes also range from the well understood, e.g. energetic particle interactions with matter, to the still incompletely researched, such as radiation transfer in optically thick electron positron plasmas in intense neutron star magnetic fields.

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

PubMed

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

2018-05-10

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

Simulated and measured neutron/gamma light output distribution for poly-energetic neutron/gamma sources

NASA Astrophysics Data System (ADS)

Hosseini, S. A.; Zangian, M.; Aghabozorgi, S.

2018-03-01

In the present paper, the light output distribution due to poly-energetic neutron/gamma (neutron or gamma) source was calculated using the developed MCNPX-ESUT-PE (MCNPX-Energy engineering of Sharif University of Technology-Poly Energetic version) computational code. The simulation of light output distribution includes the modeling of the particle transport, the calculation of scintillation photons induced by charged particles, simulation of the scintillation photon transport and considering the light resolution obtained from the experiment. The developed computational code is able to simulate the light output distribution due to any neutron/gamma source. In the experimental step of the present study, the neutron-gamma discrimination based on the light output distribution was performed using the zero crossing method. As a case study, 241Am-9Be source was considered and the simulated and measured neutron/gamma light output distributions were compared. There is an acceptable agreement between the discriminated neutron/gamma light output distributions obtained from the simulation and experiment.

Measuring the charged pion polarizability in the gamma gamma -> pi+pi- reaction

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

Lawrence, David W.; Miskimen, Rory A.; Mushkarenkov, Alexander Nikolaevich

2013-08-01

Development has begun of a new experiment to measure the charged pion polarizabilitymore » $$\\alpha_{\\pi}-\\beta_{\\pi}$$. The charged pion polarizability ranks among the most important tests of low-energy QCD presently unresolved by experiment. Analogous to precision measurements of $$\\pi^{\\circ}\\rightarrow\\gamma\\gamma$$ that test the intrinsic odd-parity (anomalous) sector of QCD, the pion polarizability tests the intrinsic even-parity sector of QCD. The measurement will be performed using the $$\\gamma\\gamma\\rightarrow\\pi^{+{}}\\pi^{-{}}$$ cross section accessed via the Primakoff mechanism on nuclear targets using the GlueX detector in Hall D at Jefferson Lab. The linearly polarized photon source in Hall-D will be utilized to separate the Primakoff cross-section from coherent $$\\rho^{\\circ}$$ production.« less

Future prospects for gamma-ray

NASA Technical Reports Server (NTRS)

Fichtel, C.

1980-01-01

Astrophysical phenomena discussed are: the very energetic and nuclear processes associated with compact objects; astrophysical nucleo-synthesis; solar particle acceleration; the chemical composition of the planets and other bodies of the solar system; the structure of our galaxy; the origin and dynamic pressure effects of the cosmic rays; the high energy particles and energetic processes in other galaxies, especially active ones; and the degree of matter antimater symmetry of the universe. The gamma ray results of GAMMA-I, the gamma ray observatory, the gamma ray burst network, solar polar, and very high energy gamma ray telescopes on the ground provide justification for more sophisticated telescopes.

Gamma ray camera

DOEpatents

Perez-Mendez, V.

1997-01-21

A gamma ray camera is disclosed for detecting rays emanating from a radiation source such as an isotope. The gamma ray camera includes a sensor array formed of a visible light crystal for converting incident gamma rays to a plurality of corresponding visible light photons, and a photosensor array responsive to the visible light photons in order to form an electronic image of the radiation therefrom. The photosensor array is adapted to record an integrated amount of charge proportional to the incident gamma rays closest to it, and includes a transparent metallic layer, photodiode consisting of a p-i-n structure formed on one side of the transparent metallic layer, and comprising an upper p-type layer, an intermediate layer and a lower n-type layer. In the preferred mode, the scintillator crystal is composed essentially of a cesium iodide (CsI) crystal preferably doped with a predetermined amount impurity, and the p-type upper intermediate layers and said n-type layer are essentially composed of hydrogenated amorphous silicon (a-Si:H). The gamma ray camera further includes a collimator interposed between the radiation source and the sensor array, and a readout circuit formed on one side of the photosensor array. 6 figs.

Histaminergic regulation of interferon-gamma (IFN-gamma) production by human natural killer (NK) cells.

PubMed

Asea, A; Hansson, M; Czerkinsky, C; Houze, T; Hermodsson, S; Strannegård, O; Hellstrand, K

1996-08-01

Monocytes, recovered from human peripheral blood by counter-current centrifugal elutriation, effectively inhibit the production of IFN-gamma by CD3-/56+ NK cells in response to IL-2. This study aimed at defining the nature of the inhibitory signal, particularly the importance of monocyte-derived reactive metabolites of oxygen. It was found that monocytes recovered from patients with chronic granulomatous disease (CGD), a condition characterized by deficient NADPH-oxidase activity of phagocytes, did not inhibit IFN-gamma production by NK cells. Further, catalase, a scavenger of hydrogen peroxide, completely reversed the inhibitory signal whereas scavengers of the superoxide anion, hypohalous acids, the hydroxyl radical, or nitric oxide synthesis inhibitors such as L-NMMA were ineffective. Inhibition of IFN-gamma production was operating on a pretranslational level, as indicated by the inability of enriched NK cells to accumulate IFN-gamma mRNA in the presence of elutriated monocytes. Hydrogen peroxide, at micromolar concentrations, reconstituted the inhibition of IFN-gamma production when added to enriched NK cells. Histamine, a biogenic amine which inhibits the generation of reactive oxygen metabolites in monocytes, abrogated the inhibition of IFN-gamma production in NK cells; by this mechanism, histamine strongly synergized with IL-2 to induce IFN-gamma in mixtures of NK cells and monocytes. The synergizing effect of histamine was specifically mediated by H2-type histamine receptors. We conclude that: (i) the induction of IFN-gamma mRNA in NK cells is effectively down-regulated by products of the oxidative metabolism of monocytes; and (ii) histamine effectively enhances IFN-gamma production by preventing monocyte-induced oxidative damage to NK cells.

Gamma ray astrophysics to the year 2000. Report of the NASA Gamma Ray Program Working Group

NASA Technical Reports Server (NTRS)

1988-01-01

Important developments in gamma-ray astrophysics up to energies of 100 GeV during the last decade are reviewed. Also, the report seeks to define the major current scientific goals of the field and proposes a vigorous program to pursue them, extending to the year 2000. The goals of gamma-ray astronomy include the study of gamma rays which provide the most direct means of studying many important problems in high energy astrophysics including explosive nucleosynthesis, accelerated particle interactions and sources, and high-energy processes around compact objects. The current research program in gamma-ray astronomy in the U.S. including the space program, balloon program and foreign programs in gamma-ray astronomy is described. The high priority recommendations for future study include an Explorer-class high resolution gamma-ray spectroscopy mission and a Get Away Special cannister (GAS-can) or Scout class multiwavelength experiment for the study of gamma-ray bursts. Continuing programs include an extended Gamma Ray Observatory mission, continuation of the vigorous program of balloon observations of the nearby Supernova 1987A, augmentation of the balloon program to provide for new instruments and rapid scientific results, and continuation of support for theoretical research. Long term recommendations include new space missions using advanced detectors to better study gamma-ray sources, the development of these detectors, continued study for the assembly of large detectors in space, collaboration with the gamma-ray astronomy missions initiated by other countries, and consideration of the Space Station attached payloads for gamma-ray experiments.

The effect of alloying on gamma and gamma prime in nickel-base superalloys

NASA Technical Reports Server (NTRS)

Dreshfield, R. L.; Wallace, J. F.

1972-01-01

An investigation was conducted to determine the compositional limits of gamma and gamma prime phases in nickel-base superalloys. Fifty-one nickel-base alloys were melted under vacuum and heat treated for 4 hours at 1190 C followed by 1008 hours at 850 C. The alloys had the following composition ranges: A1 4.0 to 13 atomic percent, Cr 6.5 to 20.5 percent, Ti 0.25 to 4.75 percent, Mo 0.0 to 6.0 percent, and W 0.0 to 4.0 percent. The residues from the ammonium sulfate electrolytic extraction for the two-phase alloys were analyzed chemically and by X-ray diffraction. The results of the investigation were used to assemble a mathematical model of the gamma-gamma prime region of the Ni-Al-Cr-Ti-Mo-W system. A computer program was written to analyze the model of the phase diagram. Some of these results are also presented graphically. The resulting model is capable of satisfactorily predicting the compositions of conjugate gamma-gamma prime phases in the alloys investigated and twelve of fifteen commercial superalloys studied.

Status of the GAMMA-400 Project

NASA Technical Reports Server (NTRS)

Galper, A. M.; Adriani, O.; Aptekar, R. L.; Arkhangelskaja, I. V.; Arkhangelskiy, A. I.; Boezio, M.; Bonvicini, V.; Boyarchuk, K. A.; Gusakov, Yu. V.; Farber, M. O.;

Formation of fine {gamma} grain structure through fine {alpha}{sub 2}/{gamma} lamellar structure in Ti-rich TiAl alloy

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

Kumagai, T.; Abe, E.; Nakamura, M.

1997-12-31

Microstructural development of an extremely fine {alpha}{sub 2}-Ti{sub 32}Al/{gamma}-TiAl lamellar structure, which was formed by ice water quenching after solution-treatment in a high-temperature {alpha}-Ti phase field for a long period of time, was examined during isothermal treatment. In an as-quenched Ti-48at.%Al alloy, the massively transformed {gamma} ({gamma}{sub m}) and untransformed (meaning massively untransformed) fine {alpha}{sub 2}/{gamma} lamellar regions were observed. Fine {gamma} grains, which were similar to {gamma}{sub m}, were generated both within the fine {alpha}{sub 2}/{gamma} lamellae and at the boundary area between the {gamma}{sub m} and the fine {alpha}{sub 2}/{gamma} lamellar regions by aging at low-temperature (1,173 K)more » for a short time (180s). Further aging (1.8ks) caused the coarsening of these newly generated fine {gamma} grains. On the other hand, the coarsening of the {gamma} grains occurred by a high-temperature (1,323 K) aging treatment even for 180s. Fine {alpha}{sub 2} plates and particles, which were aligned to a particular direction, were observed in the {gamma} grain interiors, indicating that the newly generated {gamma} grains grew at the expense of the fine {alpha}{sub 2}/{gamma} lamellae. It can be considered that the {gamma} grain formation through the fine {alpha}{sub 2}/{gamma} lamellae is closely related to the {alpha}{sub 2}{yields}{gamma} reaction of the {alpha}{sub 2} plates sandwiched by the {gamma} plates, and needs the fast heating rate enough to overcome the {alpha}{sub 2}/{gamma}{yields}{gamma}/{gamma} lamellae reaction.« less

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

PubMed

Barseem, Naglaa; Elsamalehy, Mona

2017-06-01

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

Fusion gamma diagnostics

NASA Astrophysics Data System (ADS)

Medley, S. S.; Cecil, F. E.; Cole, D.; Conway, M. A.; Wilkinson, F. J., III

1985-05-01

Nuclear reactions of interest in fusion research often possess a branch yielding prompt emission of gamma radiation in excess of 15 MeV which can be exploited to provide a new fusion reaction diagnostic having applications similar to conventional neutron emission measurements. Conceptual aspects of fusion gamma diagnostics are discussed with emphasis on application to the Tokamak Fusion Test Reactor (TFTR) during deuterium neutral beam heating of D-T and D-3He plasmas. Recent measurements of the D (T, γ)5He, D(3He, γ)5Li, and D(D, γ)4He branching ratios at low center-of-mass energy (30-100 keV) and of the response of a large volume Ne226 detector for gamma detection in high neutron backgrounds are presented. Using a well-shielded Ne226 detector during 20 MW-120 kV deuterium beam heating of a tritium plasma in TFTR, the D(T, γ)5He gamma signal level is estimated to be 3.5×105 cps.

O-GlcNAc Transferase Is Essential for Sensory Neuron Survival and Maintenance

PubMed Central

Su, Cathy

2017-01-01

O-GlcNAc transferase (OGT) regulates a wide range of cellular processes through the addition of the O-GlcNAc sugar moiety to thousands of protein substrates. Because nutrient availability affects the activity of OGT, its role has been broadly studied in metabolic tissues. OGT is enriched in the nervous system, but little is known about its importance in basic neuronal processes in vivo. Here, we show that OGT is essential for sensory neuron survival and maintenance in mice. Sensory neuron-specific knock-out of OGT results in behavioral hyposensitivity to thermal and mechanical stimuli accompanied by decreased epidermal innervation and cell-body loss in the dorsal root ganglia. These effects are observed early in postnatal development and progress as animals age. Cultured sensory neurons lacking OGT also exhibit decreased axonal outgrowth. The effects on neuronal health in vivo are not solely due to disruption of developmental processes, because inducing OGT knock-out in the sensory neurons of adult mice results in a similar decrease in nerve fiber endings and cell bodies. Significant nerve-ending loss occurs before a decrease in cell bodies; this phenotype is indicative of axonal dieback that progresses to neuronal death. Our findings demonstrate that OGT is important in regulating axonal maintenance in the periphery and the overall health and survival of sensory neurons. SIGNIFICANCE STATEMENT We show the importance of O-GlcNAc transferase (OGT) for sensory neuron health and survival in vivo. This study is the first to find that loss of OGT results in neuronal cell death. Moreover, it suggests that aberrant O-GlcNAc signaling can contribute to the development of neuropathy. The sensory neurons lie outside of the blood–brain barrier and therefore, compared to central neurons, may have a greater need for mechanisms of metabolic sensing and compensation. Peripheral sensory neurons in particular are subject to degeneration in diabetes. Our findings provide a

A gamma beam profile imager for ELI-NP Gamma Beam System

NASA Astrophysics Data System (ADS)

Cardarelli, P.; Paternò, G.; Di Domenico, G.; Consoli, E.; Marziani, M.; Andreotti, M.; Evangelisti, F.; Squerzanti, S.; Gambaccini, M.; Albergo, S.; Cappello, G.; Tricomi, A.; Veltri, M.; Adriani, O.; Borgheresi, R.; Graziani, G.; Passaleva, G.; Serban, A.; Starodubtsev, O.; Variola, A.; Palumbo, L.

2018-06-01

The Gamma Beam System of ELI-Nuclear Physics is a high brilliance monochromatic gamma source based on the inverse Compton interaction between an intense high power laser and a bright electron beam with tunable energy. The source, currently being assembled in Magurele (Romania), is designed to provide a beam with tunable average energy ranging from 0.2 to 19.5 MeV, rms energy bandwidth down to 0.5% and flux of about 108 photons/s. The system includes a set of detectors for the diagnostic and complete characterization of the gamma beam. To evaluate the spatial distribution of the beam a gamma beam profile imager is required. For this purpose, a detector based on a scintillator target coupled to a CCD camera was designed and a prototype was tested at INFN-Ferrara laboratories. A set of analytical calculations and Monte Carlo simulations were carried out to optimize the imager design and evaluate the performance expected with ELI-NP gamma beam. In this work the design of the imager is described in detail, as well as the simulation tools used and the results obtained. The simulation parameters were tuned and cross-checked with the experimental measurements carried out on the assembled prototype using the beam from an x-ray tube.